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1

Rat thymic cultures: morphological and phenotypical characterization.  

PubMed Central

Rat thymic cultures have been established in order to analyse the morpho-functional characteristics of thymic epithelial and non-epithelial cells in vitro. Stromal cultures, originating from implanted thymic fragments, consist of fibroblasts occupying most of the culture surface, epithelial cells forming discrete colonies, thymocytes and bone marrow-derived cells. Epithelial cells show a low class II MHC antigen expression, which is highly increased in semi-adherent cells, and do not interact with thymocytes. Thymocytes proliferate extensively at the beginning of the culture, but almost disappear at the end of the first week; however, restarting of thymocyte proliferation occurs during the second week of culture. Bone marrow-derived cells include ED- Ia+ CR3- IL-2R- dendritic cells (DC), ED+ Ia+ CR3+ IL-2R+ non-adherent thymic phagocytic cells (PTR) and ED+ Ia- CR3- IL-2R- adherent type 1 and 2 macrophages, derived from PTR. Both PTR and DC establish lympho-stromatic complexes with thymocytes present in the cultures. These results suggest that PTR and DC present in rat thymic cultures belong to different cell lineages, and that they are, respectively, the in vitro equivalents of intrathymic macrophages and interdigitating cells. Images Figure 1 Figure 3 Figure 4 PMID:2071161

Fontecha, A M; Alvarez, A; Navarro, R; Zapata, A; Ardavin, C

1991-01-01

2

MORPHOLOGICAL CHARACTERIZATION OF EARLY LIGATION-INDUCED ACUTE PANCREATITIS IN RATS  

PubMed Central

Background Bile-pancreatic duct ligation in rats causes acute pancreatic inflammation. We performed serial morphologic evaluation of the exocrine pancreas after duct ligation to facilitate further investigations using the model. Methods The pancreas was excised from 74 rats after 0, 1, 3, 5, 24 or 48 h of duct ligation or sham operation. A pathologist evaluated one hematoxylin- and eosin-stained slide from each rat. Confirmatory immunostaining was performed with markers for apoptosis (activated caspase-3), proliferation (cyclin D3), neutrophils (myeloperoxidase), and macrophages (CD68). Results Interstitial edema and WBC infiltration were apparent at 24 h and increased at 48 h. Progressive periods of duct ligation were characterized by ductular ectasia (1–3 h), acinar vacuolization (5–48 h), leukocytic margination and neutrophil exocytosis (5–48 h), ductule epithelium hypertrophy and proliferation (24–48 h), and discernible loss of zymogen granules (48 h). Conclusion Ligation-induced acute pancreatitis in rats is a useful model to investigate early events in disease pathogenesis. PMID:17936429

Meyerholz, David K.; Samuel, Isaac

2007-01-01

3

Morphological and physiological characterization of pyramidal neuron subtypes in rat medial prefrontal cortex.  

PubMed

The medial prefrontal cortex (mPFC) has been implicated in cognitive and executive processes including decision making, working memory and behavioral flexibility. Cortical processing depends on the interaction between distinct neuronal cell types in different cortical layers. To better understand cortical processing in the rat mPFC, we studied the diversity of pyramidal neurons using in vitro whole-cell patch clamp recordings and biocytin staining of neurons, followed by morphological analysis. Using unsupervised cluster analysis for the objective grouping of neurons, we identified more than 10 different pyramidal subtypes spread across the different cortical layers. Layer 2 pyramidal neurons possessed a unique morphology with wide apical dendritic field spans and a narrow basal field span. Layer 3 contained the only subtype that showed a burst of action potentials upon current injection. Layer 5 pyramidal neurons showed the largest voltage sags. Finally, pyramidal neurons in layer 6 (L6) showed a great variety in their morphology with 39% of L6 neurons possessing tall apical dendrites that extend into layer 1. Future experiments on the functional role of the mPFC should take into account the great diversity of pyramidal neurons. PMID:24108807

van Aerde, Karlijn I; Feldmeyer, Dirk

2015-03-01

4

Functional and morphological characterization of glutamate transporters in the rat locus coeruleus  

PubMed Central

Background and Purpose Excitatory amino acid transporters (EAATs) in the CNS contribute to the clearance of glutamate released during neurotransmission. The aim of this study was to explore the role of EAATs in the regulation of locus coeruleus (LC) neurons by glutamate. Experimental Approach We measured the effect of different EAAT subtype inhibitors/enhancers on glutamate- and KCl-induced activation of LC neurons in rat slices. EAAT2–3 expression in the LC was also characterized by immunohistochemistry. Key Results The EAAT2–5 inhibitor DL-threo-?-benzyloxaspartic acid (100 ?M), but not the EAAT2, 4, 5 inhibitor L-trans-pyrrolidine-2,4-dicarboxylic acid (100 ?M) or the EAAT2 inhibitor dihydrokainic acid (DHK; 100 ?M), enhanced the glutamate- and KCl-induced activation of the firing rate of LC neurons. These effects were blocked by ionotropic, but not metabotrobic, glutamate receptor antagonists. DHK (100 ?M) was the only EAAT inhibitor that increased the spontaneous firing rate of LC cells, an effect that was due to inhibition of EAAT2 and subsequent AMPA receptor activation. Chronic treatment with ceftriaxone (200 mg·kg?1 i.p., once daily, 7 days), an EAAT2 expression enhancer, increased the actions of glutamate and DHK, suggesting a functional impact of EAAT2 up-regulation on the glutamatergic system. Immuhistochemical data revealed the presence of EAAT2 and EAAT3 surrounding noradrenergic neurons and EAAT2 on glial cells in the LC. Conclusions and Implications These results remark the importance of EAAT2 and EAAT3 in the regulation of rat LC by glutamate. Neuronal EAAT3 would be responsible for terminating the action of synaptically released glutamate, whereas glial EAAT2 would regulate tonic glutamate concentrations in this nucleus. PMID:23638698

Medrano, M C; Gerrikagoitia, I; Martínez-Millán, L; Mendiguren, A; Pineda, J

2013-01-01

5

Microcomputed Tomography with Diffraction-Enhanced Imaging for Morphologic Characterization and Quantitative Evaluation of Microvessel of Hepatic Fibrosis in Rats  

PubMed Central

Backgroud Hepatic fibrosis can lead to deformation of vessel morphology and structure. In the present feasibility study, high-resolution computed tomography (CT) using diffraction-enhanced imaging (DEI) was used to represent three-dimensional (3D) vessel microstructures of hepatic fibrosis in rats and to differentiate different stages of hepatic fibrosis using qualitative descriptions and quantitative measurement of microvessels. Material and Methods Three typical specimens at different stages, i.e., mild, moderate and severe hepatic fibrosis, were imaged using DEI at 15 keV without contrast agents. The correspondence between DEI-CT images and histopathological findings was determined. The 3D visualizations from different stages of hepatic fibrosis were presented using DEI-CT. Additionally, Qualitative descriptions and quantitative evaluation of vessel features, such as vessel trend, vascular distortion deformation, thrombus formation and texture features on the inner wall of the vessel, were performed. Results DEI-CT produced high-resolution images of the vessel microstructures in hepatic fibrosis that corresponded to information on actual structures observed from the histological sections. Combined with the 3D visualization technique, DEI-CT enabled the acquisition of an accurate description of the 3D vessel morphology from different stages of hepatic fibrosis. Qualitative descriptions and quantitative assessment of microvessels demonstrated clear differences between the different stages of hepatic fibrosis. The thrombus inside the vessel of severe liver fibrosis was accurately displayed, and corresponding analysis can provide an exact measurement of vessel stenosis rate. Conclusions DEI-CT may allow morphologic descriptions and quantitative evaluation of vessel microstructures from different stages of hepatic fibrosis and can better characterize the various stages of fibrosis progression using high-resolution 3D vessel morphology. PMID:24205147

Duan, Jinghao; Hu, Chunhong; Luo, Shuqian; Zhao, Xinyan; Wang, Tailing

2013-01-01

6

Transcellular transport of polymeric IgA in the rat hepatocyte: biochemical and morphological characterization of the transport pathway  

PubMed Central

Polymeric IgA (pIgA) is transported by liver parenchymal cells (hepatocytes) from blood to bile via a receptor-mediated process. We have studied the intracellular pathway taken by a TEPC15 mouse myeloma pIgA. When from 1 microgram to 1 mg 125I-pIgA was injected into the saphenous vein of a rat, 36% was transported as intact protein into the bile over a 3-h period. The concentration of transported 125I-pIgA was maximal in bile 30-60 min after injection, and approximately 80% of the total 125I-pIgA ultimately transported had been secreted into bile by 90 min. A horseradish peroxidase-pIgA conjugate (125I-pIgA-HRP) was transported to a similar extent and with kinetics similar to that of unconjugated 125I-pIgA and was therefore used to visualize the transport pathway. Peroxidase cytochemistry of livers fixed in situ 2.5 to 10 min after 125I-pIgA-HRP injection demonstrated a progressive redistribution of labeled structures from the sinusoidal area to intermediate and bile canalicular regions of the hepatocyte cytoplasm. Although conjugate-containing structures began accumulating in the bile canalicular region at these early times, no conjugate was present in bile until 20 min. From 7.5 to 45 min after injection approximately 30% of the labeled structures were in regions that contained Golgi complexes and lysosomes; however, we found no evidence that either organelle contained 125I-pIgA-HRP. At least 85% of all positive structures in the hepatocyte were vesicles of 110-160-nm median diameters, with the remaining structures accounted for by tubules and multivesicular bodies. Vesicles in the bile canalicular region tended to be larger than those in the sinusoidal region. Serial sectioning showed that the 125I-pIgA-HRP-containing structures were relatively simple (predominantly vesicular) and that extensive interconnections did not exist between structures in the sinusoidal and bile canalicular regions. PMID:4066752

1985-01-01

7

Ecto-nucleoside triphosphate diphosphohydrolase 3 in the ventral and lateral hypothalamic area of female rats: morphological characterization and functional implications  

PubMed Central

Background Based on its distribution in the brain, ecto-nucleoside triphosphate diphosphohydrolase 3 (NTPDase3) may play a role in the hypothalamic regulation of homeostatic systems, including feeding, sleep-wake behavior and reproduction. To further characterize the morphological attributes of NTPDase3-immunoreactive (IR) hypothalamic structures in the rat brain, here we investigated: 1.) The cellular and subcellular localization of NTPDase3; 2.) The effects of 17?-estradiol on the expression level of hypothalamic NTPDase3; and 3.) The effects of NTPDase inhibition in hypothalamic synaptosomal preparations. Methods Combined light- and electron microscopic analyses were carried out to characterize the cellular and subcellular localization of NTPDase3-immunoreactivity. The effects of estrogen on hypothalamic NTPDase3 expression was studied by western blot technique. Finally, the effects of NTPDase inhibition on mitochondrial respiration were investigated using a Clark-type oxygen electrode. Results Combined light- and electron microscopic analysis of immunostained hypothalamic slices revealed that NTPDase3-IR is linked to ribosomes and mitochondria, is predominantly present in excitatory axon terminals and in distinct segments of the perikaryal plasma membrane. Immunohistochemical labeling of NTPDase3 and glutamic acid decarboxylase (GAD) indicated that ?-amino-butyric-acid- (GABA) ergic hypothalamic neurons do not express NTPDase3, further suggesting that in the hypothalamus, NTPDase3 is predominantly present in excitatory neurons. We also investigated whether estrogen influences the expression level of NTPDase3 in the ventrobasal and lateral hypothalamus. A single subcutaneous injection of estrogen differentially increased NTPDase3 expression in the medial and lateral parts of the hypothalamus, indicating that this enzyme likely plays region-specific roles in estrogen-dependent hypothalamic regulatory mechanisms. Determination of mitochondrial respiration rates with and without the inhibition of NTPDases confirmed the presence of NTPDases, including NTPDase3 in neuronal mitochondria and showed that blockade of mitochondrial NTPDase functions decreases state 3 mitochondrial respiration rate and total mitochondrial respiratory capacity. Conclusion Altogether, these results suggest the possibility that NTPDases, among them NTPDase3, may play an estrogen-dependent modulatory role in the regulation of intracellular availability of ATP needed for excitatory neuronal functions including neurotransmission. PMID:19383175

Kiss, David S; Zsarnovszky, Attila; Horvath, Krisztina; Gyorffy, Andrea; Bartha, Tibor; Hazai, Diana; Sotonyi, Peter; Somogyi, Virag; Frenyo, Laszlo V; Diano, Sabrina

2009-01-01

8

Time course characterization of serum cardiac troponins, heart fatty acid-binding protein, and morphologic findings with isoproterenol-induced myocardial injury in the rat.  

PubMed

We investigated the kinetics of circulating biomarker elevation, specifically correlated with morphology in acute myocardial injury. Male Hanover Wistar rats underwent biomarker and morphologic cardiac evaluation at 0.5 to seventy-two hours after a single subcutaneous isoproterenol administration (100 or 4000 microg/kg). Dose-dependent elevations of serum cardiac troponins I and T (cTnI, cTnT), and heart fatty acid-binding protein (H-FABP) occurred from 0.5 hour, peaked at two to three hours, and declined to baseline by twelve hours (H-FABP) or forty-eight to seventy-two hours (Serum cTns). They were more sensitive in detecting cardiomyocyte damage than other serum biomarkers. The Access 2 platform, an automated chemiluminescence analyzer (Beckman Coulter), showed the greatest cTnI fold-changes and low range sensitivity. Myocardial injury was detected morphologically from 0.5 hour, correlating well with loss of cTnI immunoreactivity and serum biomarker elevation at early time points. Ultrastructurally, there was no evidence of cardiomyocyte death at 0.5 hour. After three hours, a clear temporal disconnect occurred: lesion scores increased with declining cTnI, cTnT, and H-FABP values. Serum cTns are sensitive and specific markers for detecting acute/active cardiomyocyte injury in this rat model. Heart fatty acid-binding protein is a good early marker but is less sensitive and nonspecific. Release of these biomarkers begins early in myocardial injury, prior to necrosis. Assessment of cTn merits increased consideration for routine screening of acute/ongoing cardiomyocyte injury in rat toxicity studies. PMID:20585145

Clements, Peter; Brady, Sally; York, Malcolm; Berridge, Brian; Mikaelian, Igor; Nicklaus, Rosemary; Gandhi, Mitul; Roman, Ian; Stamp, Clare; Davies, Dai; McGill, Paul; Williams, Thomas; Pettit, Syril; Walker, Dana; Turton, John

2010-08-01

9

[Characterization of Marburg virus morphology].  

PubMed

Ebola virus (EBOV) and Marburg virus (MARV) belong to the family Filoviridae. Filoviruses cause severe filovirus hemorrhagic fever (FHF) in humans, with high case fatality rates, and represent potential agents for bioterrorism and biological weapons. It is necessary to keep surveillance of filoviruses, even though there is no report of their isolation and patients in China so far. To characterize MARV morphology, the Lake Victoria marburgvirus--Leiden was stained negatively and observed under a transmission electron microscope which is one of important detection methods for filoviruses in emergencies and bioterrorism. MARV showed pleomorphism, with filamentous, rod-shaped, cobra-like, spherical, and branch-shaped particles of uniform diameter but different lengths. Pleomorphism of negatively stained MARV is summarized in this article, so as to provide useful information for possible electron microscopic identification of filoviruses in China. PMID:25118385

Song, Jing-Dong; Qu, Jian-Guo; Hong, Tao

2014-05-01

10

Morphological Characterization of Silicone Hydrogels  

NASA Astrophysics Data System (ADS)

Silicone hydrogel materials are used in the latest generation of extended wear soft contact lenses. To ensure comfort and eye health, these materials must simultaneously exhibit high oxygen permeability and high water permeability / hydrophilicity. The materials achieve these opposing requirements based on bicontinuous composite of nanoscale domains of oxygen permeable (silicones) and hydrophilic (water soluble polymer) materials. The microphase separated morphology of silicone hydrogel contact lens materials was imaged using field emission gun scanning transmission electron microscopy (FEGSTEM), and atomic force microscopy (AFM). Additional morphological information was provided by small angle X-ray scattering (SAXS). These results all indicate a nanophase separated structure of silicone rich (oxygen permeable) and carbon rich (water soluble polymer) domains separated on a length scale of about 10 nm.

Gido, Samuel

2007-03-01

11

Chronic Stress Alters Dendritic Morphology in Rat Medial Prefrontal Cortex  

E-print Network

Chronic Stress Alters Dendritic Morphology in Rat Medial Prefrontal Cortex Susan C. Cook,1 Cara L ABSTRACT: Chronic stress produces deficits in cognition accompanied by alterations in neural chemis- try and morphology. Medial prefrontal cortex is a target for glucocorticoids involved in the stress response. We have

Wellman, Cara

12

Morphological characterization of point patterns.  

PubMed

A triplet of function s for the statistical characterization of planar point patterns is introduced. They are related to the integral-geometric quantities area, boundary length and Euler number of patterns of discs centred at the given points. These functions are able to give information on the distribution of a given point pattern which the traditional summary statistics of point process theory do not offer and so can lead to an improved statistical description. The paper describes the statistical estimation of the new characteristics. Some examples illustrate their application in the exploratory analysis of point patterns of tree positions in forests, in comparison to results obtained by means of second-order and distance characteristics. PMID:16161805

Mecke, K R; Stoyan, D

2005-08-01

13

Plastic solar cell interface and morphological characterization  

NASA Astrophysics Data System (ADS)

Plastic solar cell research has become an intense field of study considering these devices may be lightweight, flexible and reduce the cost of photovoltaic devices. The active layer of plastic solar cells are a combination of two organic components which blend to form an internal morphology. Due to the poor electrical transport properties of the organic components it is important to understand how the morphology forms in order to engineer these materials for increased efficiency. The focus of this thesis is a detailed study of the interfaces between the plastic solar cell layers and the morphology of the active layer. The system studied in detail is a blend of P3HT and PCBM that acts as the primary absorber, which is the electron donor, and the electron acceptor, respectively. The key morphological findings are, while thermal annealing increases the crystallinity parallel to the substrate, the morphology is largely unchanged following annealing. The deposition and mixing conditions of the bulk heterojunction from solution control the starting morphology. The spin coating speed, concentration, solvent type, and solution mixing time are all critical variables in the formation of the bulk heterojunction. In addition, including the terminals or inorganic layers in the analysis is critical because the inorganic surface properties influence the morphology. Charge transfer in the device occurs at the material interfaces, and a highly resistive transparent conducting oxide layer limits device performance. It was discovered that the electron blocking layer between the transparent conducting oxide and the bulk heterojunction is compromised following annealing. The electron acceptor material can diffuse into this layer, a location which does not benefit device performance. Additionally, the back contact deposition is important since the organic material can be damaged by the thermal evaporation of Aluminum, typically used for plastic solar cells. Depositing a thin thermal and momentum blocking layer of lithium fluoride prevents damage which ultimately leads to higher efficiencies. Finally, new materials have been synthesized with better electronic properties and stability. Characterization of the polymer properties and how they assemble is important for high device performance. One new promising polymer, Polybenzo[1,2-b:4,5- b']dithiophene-4,7-dithien-2-yl-2,1,3-benzothiadiazole (PBnDT-DTBT), was characterized with PCBM and it was found that this polymer assembles similarly to previously studied polymers. The efficiency gained with this new polymer is obtained from an improvement in the materials electronic properties since the morphology closely resembles the P3HT:PCBM system.

Guralnick, Brett W.

14

Morphology of aortic depressor nerve myelinated fibers in normotensive Wistar–Kyoto and spontaneously hypertensive rats  

Microsoft Academic Search

Reports on the morphology of the baroreceptor terminal of spontaneously hypertensive rats (SHR) did not demonstrate any difference when compared to the axonal terminal of normotensive rats. Although several studies reporting baroreceptor terminal and blood vessel wall morphology have been carried out to better understand the baroreceptor function and resetting to hypertensive levels, there are no reports examining the morphology

Valéria Paula Sassoli Fazan; Rubens Fazan; Helio Cesar Salgado; Amilton Antunes Barreira

1999-01-01

15

Morphological Changes in Rat Vestibular System Following Weightlessness  

NASA Technical Reports Server (NTRS)

Mammalian gravity receptors (maculas) are morphologically organized for weighted, parallel distributed processing of information. There are two basic circuits: 1) highly channeled, type I cell to calyx; and 2) distributed modifying, type II cells to calyces and processes. The latter circuit should be the more adaptable since it modifies final output. To test this hypothesis, rats were flown in microgravity for 9 days aboard a space shuttle and euthanized shortly after landing. Hair cells and ribbon synapses from maculas of 3 flight and 3 ground control rats were studied ultrastructurally in blocks of 50 serial sections. Synapses increased by approximately 41% in type I cells and by approximately 55% in type II cells in flight animals. There was a shift toward the spherular form of ribbon synapse in both types of hair cells in flight animals. Current findings tend to support the stated hypothesis and indicate that mature utricular hair cells retain synaptic plasticity, permitting adaptation to an altered gravitational environment.

Ross, Muriel D.

1993-01-01

16

Myocardial morphology and cardiac function in rats with renal failure.  

PubMed

The effects of chronic renal failure on cardiac performance and myocardial morphology were studied in rats: 17 with 5/6 nephrectomy (CRF rats) and 12 with sham operation (controls). Cardiac function was assessed 8 weeks postoperatively, using the Langendorff technique for an isolated working heart model. After the hemodynamic study the hearts were fixed for electron and light microscopy. In the CRF rats left ventricular systolic pressure was significantly higher at all preloads (10-20 cmH2O) and afterloads (70-90 cmH2O), and left ventricular stroke work was significantly increased at preload 20 cmH2O with afterloads 70 or 90 cmH2O. Light microscopy revealed fibronecrotic lesions consisting of fibroblastic proliferation with newly formed collagen interposed between or entrapping degenerative myocytes. The changes were focally distributed, with perivascular accentuation and were most frequent in the basal half of the ventricular wall. Electron microscopy of non-necrotic myocytes showed intact myocytes, with mitochondria morphometrically similar in the 2 groups, but a significantly lower incidence of mitochondrial granules in the CRF rats. Thus 8 weeks of CRF showed no cardiac dysfunction associated with the focally distributed fibronecrotic myocardial lesions and decrease in mitochondrial granules. The precise mechanism of the discrepancy between the morphological change and the cardiac function is unclear. One possible explanation may be that because the pathological changes in the myocardium were focal or mild to moderate, some compensation mechanism may be involved or it may be the turning point of functional change from acute renal failure to the chronic state. PMID:10952158

Hatori, N; Havu, N; Hofman-Bang, C; Clyne, N; Pehrsson, S K

2000-08-01

17

Regional differences in rat vaginal smooth muscle contractility and morphology.  

PubMed

The objective of this study was to define the regional differences in rat vaginal smooth muscle contractility and morphology. We evaluated circumferential segments from the proximal, middle, and distal rat vagina (n = 21) in vitro. Contractile responses to carbachol, phenylephrine, potassium chloride, and electrical field stimulation (EFS) were measured. Immunohistochemical analyses were also performed. The dose-response curves for carbachol- and phenylephrine-dependent contractions were different in the distal (P = .05, P = .04) compared to the proximal/middle regions. Adjusted for region-dependent changes in contractility, the distal vagina generated lower force in response to carbachol and higher force in response to phenylephrine. There was less force with increasing EFS frequency in the distal (P = .03), compared to the proximal/middle regions. Cholinergic versus adrenergic nerves were more frequent in the proximal region (P = .03). In summary, the results indicate that functional and morphological differences in smooth muscle and nerve fibers of the distal versus proximal/middle regions of the vagina exist. PMID:23298869

Skoczylas, Laura C; Jallah, Zegbeh; Sugino, Yoshio; Stein, Suzan E; Feola, Andrew; Yoshimura, Naoki; Moalli, Pamela

2013-04-01

18

Regional Differences in Rat Vaginal Smooth Muscle Contractility and Morphology  

PubMed Central

The objective of this study was to define the regional differences in rat vaginal smooth muscle contractility and morphology. We evaluated circumferential segments from the proximal, middle, and distal rat vagina (n = 21) in vitro. Contractile responses to carbachol, phenylephrine, potassium chloride, and electrical field stimulation (EFS) were measured. Immunohistochemical analyses were also performed. The dose–response curves for carbachol- and phenylephrine-dependent contractions were different in the distal (P = .05, P = .04) compared to the proximal/middle regions. Adjusted for region-dependent changes in contractility, the distal vagina generated lower force in response to carbachol and higher force in response to phenylephrine. There was less force with increasing EFS frequency in the distal (P = .03), compared to the proximal/middle regions. Cholinergic versus adrenergic nerves were more frequent in the proximal region (P = .03). In summary, the results indicate that functional and morphological differences in smooth muscle and nerve fibers of the distal versus proximal/middle regions of the vagina exist. PMID:23298869

Skoczylas, Laura C.; Jallah, Zegbeh; Sugino, Yoshio; Stein, Suzan E.; Feola, Andrew; Yoshimura, Naoki

2013-01-01

19

Teat Morphology Characterization With 3D Imaging.  

PubMed

The objective of this study was to visualize, in a novel way, the morphological characteristics of bovine teats to gain a better understanding of the detailed teat morphology. We applied silicone casting and 3D digital imaging in order to obtain a more detailed image of the teat structures than that seen in previous studies. Teat samples from 65 dairy cows over 12 months of age were obtained from cows slaughtered at an abattoir. The teats were classified according to the teat condition scoring used in Finland and the lengths of the teat canals were measured. Silicone molds were made from the external teat surface surrounding the teat orifice and from the internal surface of the teat consisting of the papillary duct, Fürstenberg's rosette, and distal part of the teat cistern. The external and internal surface molds of 35 cows were scanned with a 3D laser scanner. The molds and the digital 3D models were used to evaluate internal and external teat surface morphology. A number of measurements were taken from the silicone molds. The 3D models reproduced the morphology of the teats accurately with high repeatability. Breed didn't correlate with the teat classification score. The rosette was found to have significant variation in its size and number of mucosal folds. The internal surface morphology of the rosette did not correlate with the external surface morphology of the teat implying that it is relatively independent of milking parameters that may impact the teat canal and the external surface of the teat. Anat Rec, 2014. © 2014 Wiley Periodicals, Inc. PMID:25382725

Vesterinen, Heidi M; Corfe, Ian J; Sinkkonen, Ville; Iivanainen, Antti; Jernvall, Jukka; Laakkonen, Juha

2014-11-01

20

Morphological Correlates of Triadic Circuitry in the Lateral Geniculate Nucleus of Cats and Rats  

E-print Network

Morphological Correlates of Triadic Circuitry in the Lateral Geniculate Nucleus of Cats and Rats Y in the lateral geniculate nucleus of cats and rats. J Neurophysiol 93: 748­757, 2005; doi: 10.1152/jn.00256.2004. We used an in vitro slice preparation of the lateral geniculate nucleus in cats and rats to study

Sherman, S. Murray

21

Water maze performance of aged Sprague-Dawley rats in relation to retinal morphologic measures  

Microsoft Academic Search

The spatial learning ability of aged male and female Sprague-Dawley rats was assessed using the Morris water maze. To determine the influence of age-related visual deficits on performance levels, retinal morphologic measures were correlated with water maze performance for each rat. Rats were first trained on the water maze task at 21 months of age and were retrained 3 or

Robert L. Spencer; W. Keith O'Steen; Bruce S. McEwen

1995-01-01

22

Morphological and biochemical action of dipyrone on rat placenta.  

PubMed

1. The morphological and biochemical action of dipyrone (N-[2,3-dimethyl-5-oxo-1-phenyl-3-pyrazolin-4-yl]-methylamino methanesulfonate, sodium monohydrate) on the placenta of albino rats was studied by means of karyometry of trophoblastic giant cells and by determinations of DNA, RNA and total protein contents. 2. The animals were treated with a single daily dose of 50 mg/kg body weight during 5 different periods: from the 9th to the 12th, 11th to the 14th, 13th to the 16th, 15th to the 18th or 17th to the 20th day of pregnancy. 3. Karyometric results showed that the nuclear volumes of placental cells in rats treated with dipyrone during the first 3 periods were significantly greater than in control animals and that, closer to term, no differences were observed in this regard. Only the animals treated from the 9th to the 12th day of pregnancy had higher placental contents of DNA, RNA and protein than the corresponding controls. 4. Our results showed that dipyrone had a blocking effect on placental cell division which occurs mainly in the initial steps of placental development. PMID:8723534

Espiridiäo, S; Oliveira-Filho, R M; Doine, A; Simöes, M J; Focchi, G R; Evęncio Neto, J; Kopelman, B I; Kulay Júnior, L

1996-04-01

23

Morphological evidence of paracellular transport in perfused rat submandibular glands.  

PubMed

The morphological change of the paracellular route for fluid secretion is still a long-standing question. The purpose of this study was to visualize alterations in the cytoskeleton structure of tight junctions caused by carbachol (CCh) and isoproterenol (IPR) treatment of perfused rat submandibular glands (SMGs), using freeze-fracture (FF) replicas of rapidly frozen tissues. Isolated SMGs from male Wistar rats were perfused and stimulated with 1 microM CCh and IPR. Specimens were immediately rapidly frozen with liquid helium by metal contact. After cutting and deep etching, FF replicas were obtained by rotary shadowing and were examined by transmission electron microscopy. After CCh/IPR stimulation, the strand particles of TJs rearranged with free ends and terminal loops. In the vertical fracture surface, cytoskeletal filaments beneath the plasma membrane were arranged in a thicker layer than those of the gland without stimulation. Contraction of the submembranous actin cytoskeleton during exocytosis elicited by CCh/IPR may cause rearrangement of TJ strands due to direct interactions between the TJ membrane particles and actin filaments via the tiny bridging structures. The rearrangement and movement of TJ membrane particles involves reconstruction of the subluminal membranous actin filament network through the intermediary of interstitial molecules and may modulate increased paracellular permeability after CCh/IPR stimulation. PMID:20224237

Hashimoto, Sadamitsu; Murakami, Masataka

2009-01-01

24

Placental morphology of rats prenatally exposed to methyl parathion.  

PubMed

Although prenatal exposure to pesticides has been associated with numerous adverse reproductive effects, data on the effects of such toxics in the placenta is limited. Thus, the present study was carried out to determine the morphology of the rat placenta exposed to the organophosphate pesticide methyl parathion (MP) in ad libitum fed and restricted diet animals. The pregnant females were randomly divided into control groups and experimental groups, the latter of which received MP at the doses of 0.0, 1.0, 1.5 and 2.0 mg/kg. Most cells in the maternal-fetal interface showed significant alterations in the presence of MP. Trophoblast giant cells exhibited either prominent characteristics of degeneration or normal morphology with many phagosome vacuoles, apparently containing cell debris. Vascular congestion was also more frequent in the labyrinth of the treated animals. Areas of fibrosis and hemorrhage were found in the decidua, as well as decidual cells presenting pyknotic nuclei and acidophilic cytoplasm. In the placentas of females treated with both restricted diet and MP, such changes were much more severe. Together, these alterations suggest a direct, toxic effect of MP on the placental cells. The phagocytic activity exhibited by trophoblast cells, may be playing a role in the removal of death cells from the maternal-placental interface and/or in a compensatory mechanism to maintain the uptake of maternal nutrients, following decreased metabolic exchange functions of the labyrinth due to the toxic effect of the MP. PMID:15384254

Levario-Carrillo, Margarita; Olave, María Elena; Corral, Dora Chávez; Alderete, Jaime Gutiérrez; Gagioti, Sonia María; Bevilacqua, Estela

2004-07-01

25

Testicular morphology and cauda epididymal sperm reserves of male rats exposed to Nigerian Qua Iboe Brent crude oil  

PubMed Central

Potential negative effects of exposure to Nigerian Qua Iboe Brent crude oil on the reproductive system of male rats was investigated. Forty Sprague-Dawley rats were used for the experiment. Exposure to Nigerian Qua Iboe Brent crude oil was achieved via oral administration of increasing doses (0.1, 0.2, and 0.4 ml/rat) every other day for 4 weeks. Cauda epididymal sperm reserves and relative weights of the testes as well as histological features of the testes of rats that received the crude oil treatment were compared to those of control rats. The results described here showed a significant (p < 0.01) dose-dependent reduction in the cauda epididymal sperm reserves of rats that received crude oil treatment relative to the control group. The morphology of testes of the crude oil-exposed rats was characterized by the presence of interstitial exudates, degeneration, and necrosis of spermatogenic and interstitial (Leydig) cells. Findings indicate that exposure of male rats to Nigerian Qua Iboe Brent crude oil may have adversely affected their reproductive systems. This may imply possible reproductive health hazards for animals and humans that may be exposed to this environmental pollutant, especially in areas where oil spillage is a common feature. PMID:17322767

Maduabuchi, Igwebuike U.; Olumuyiwa, Shoyinka S.V.

2007-01-01

26

Hypertension promotes islet morphological changes with vascular injury on pre-diabetic status in SHRsp rats.  

PubMed

Abstract Hypertensive patients have a higher incidence of new-onset diabetic mellitus than normotensive subjects, and we hypothesized that hypertension induces morphological changes in islets via vascular injury. To test our hypothesis, we administrated hydralazine or irbesartan to spontaneously hypertensive stroke-prone (SHRsp) rats. A greater islet fibrosis was observed in SHRsp rats compared with controls, and irbesartan significantly ameliorated the fibrosis. High fat diet induced glucose intorelance in SHRsp rats and irbesartan but not hydralazine improved glucose torelance. We demonstrate islet morphological changes in hypertensive rats, and our data suggest that angiotensin receptor blockers have the potential to prevent islet injury. PMID:23786428

Satoh, Minoru; Nagasu, Hajime; Haruna, Yoshisuke; Ihoriya, Chieko; Kadoya, Hiroyuki; Sasaki, Tamaki; Kashihara, Naoki

2014-01-01

27

Isolation and characterization of rat plasma fibronectin.  

PubMed Central

Rat plasma fibronectin has been isolated and characterized and monospecific antibodies were prepared to it. Two components of fresh rat plasma (in the presence of proteinase inhibitors) bound to a gelatin-Sepharose affinity column. One protein was eluted with 4.0 M-urea and was identified as fibronectin. Another protein was eluted from the gelatin-Sepharose column with 8.0 M-urea and was identified as a 70 000-Mr collagen-binding molecule. This 70 000-Mr fragment was found to be a normal constituent of blood plasma, and its presence did not represent a proteolytic degradation product formed during isolation. The antibodies prepared against rat fibronectin only weakly cross-reacted with plasma fibronectins of chicken, horse and human. These studies shed light on the metabolic interrelationships between fibronectin and other collagen-binding molecules. Images Fig. 2. PLATE 1 PMID:7034721

Weiss, R E; Reddi, A H

1981-01-01

28

Characterizing cluster morphology using vector-valued Minkowski functionals  

E-print Network

The morphology of galaxy clusters is quantified using Minkowski functionals, especially the vector-valued ones, which contain directional information and are related to curvature centroids. The asymmetry of clusters and the amount of their substructure can be characterized in a unique way using these measures. -- We briefly introduce vector-valued Minkowski functionals (also known as Querma\\ss vectors) and suggest their application to cluster data in terms of a morphological characterization of excursion sets. Furthermore, we develop robust structure functions which describe the dynamical state of a cluster and study the evolution of clusters using numerical simulations.

Claus Beisbart; Thomas Buchert

1997-11-04

29

Morphological characterization of furfuraldehyde resins adsorbents  

SciTech Connect

Sugar cane is one of the most traditional plantation cultivated crops in large areas in Brazil. The State University of the North of Rio de Janeiro, UENF, is currently engaged in a program aimed to exploit the potentialities of sugar cane industry as a self sustained non-polluting enterprise. One of the projects being carried out at the UENF is the transformation of sugar cane bagasse in precursor materials for the industry of furan derivatives such as the furfuraldehyde resins obtained by acid catalysis. The possibility of employing acid catalyzed furfuraldehyde resins as selective adsorbents has arisen during a comprehensive study of physical-chemical adsorption properties of these materials. The morphology of these resins depend on the synthesis method. Scanning Electron Microscopic studies of these materials which were synthesized, in bulk (FH-M) and solution (FH-D), showed differences in surface density and particle size. Using mercury porosimeter techniques and BET adsorption methods, it was found different pore size distributions and a decrement in surface area when solvent was employed in the synthesis process. By thermogravimetric analysis it was found similar weight losses (6%) of water adsorption and a small differences in thermal stabilities.

Sanchez, R.; Monteiro, S.N. [State Univ. of the North of Rio de Janeiro (Brazil); D`Almeida, J.R. [Rio de Janeiro-Catholic Univ. (Brazil)

1996-12-31

30

Characterizing the morphology of protein binding patches.  

PubMed

Let the patch of a partner in a protein complex be the collection of atoms accounting for the interaction. To improve our understanding of the structure-function relationship, we present a patch model decoupling the topological and geometric properties. While the geometry is classically encoded by the atomic positions, the topology is recorded in a graph encoding the relative position of concentric shells partitioning the interface atoms. The topological-geometric duality provides the basis of a generic dynamic programming-based algorithm comparing patches at the shell level, which may favor topological or geometric features. On the biological side, we address four questions, using 249 cocrystallized heterodimers organized in biological families. First, we dissect the morphology of binding patches and show that Nature enjoyed the topological and geometric degrees of freedom independently while retaining a finite set of qualitatively distinct topological signatures. Second, we argue that our shell-based comparison is effective to perform atomic-level comparisons and show that topological similarity is a less stringent than geometric similarity. We also use the topological versus geometric duality to exhibit topo-rigid patches, whose topology (but not geometry) remains stable upon docking. Third, we use our comparison algorithms to infer specificity-related information amidst a database of complexes. Finally, we exhibit a descriptor outperforming its contenders to predict the binding affinities of the affinity benchmark. The softwares developed with this article are availablefrom http://team.inria.fr/abs/vorpatch_compatch/. PMID:22806945

Malod-Dognin, Noël; Bansal, Achin; Cazals, Frédéric

2012-12-01

31

Effect of exercise training and dietary fat on rat adipose tissue lipolysis and morphology  

E-print Network

EFFECT OF EXERCISE TRAINING AND DIETARY FAT ON RAT ADIPOSE TISSUE LIPOLYSIS AND MORPHOLOGY A Thesis by SONIA BARSTAD NEALZ Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1989 Major Subject: Nutrition EFFECT OF EXERCISE TRAINING AND DIETARY FAT ON RAT ADIPOSE TISSUE LIPOLYSIS AND MORPHOLOGY A Thesis by SONIA BARSTAD NEALE Approved as to style and content by: Karen S. Kubena (Co...

Neale, Sonia Barstad

1989-01-01

32

Disturbances of morphological parameters in blood of rats orally exposed to aluminum chloride  

Microsoft Academic Search

The aim of this work was to assess changes of morphological parameters in the blood of rats after oral (po) administration\\u000a of aluminum (Al), in relation to the time and the administered dose. The experiment was performed on female Wistar rats. The\\u000a animals were administered aluminum chloride (100 mg Al\\/kg) daily for 21 d. Morphological assays: red blood cells (RBC),

Jadwiga Chmielnicka; Marzenna Nasiadek; Roman Pínkowski; Marek Paradowski

1994-01-01

33

Morphological and cytohistochemical evaluation of renal effects of cadmium-doped silica nanoparticles given intratracheally to rat  

NASA Astrophysics Data System (ADS)

Renal morphological parameters were determined in rats intratracheally instilled with model cadmium-containing silica nanoparticles (Cd-SiNPs, 1mg/rat), also exploring whether their potential modifications would be associated with toxicogenomic changes. Cd-SiNP effects, evaluated 7 and 30 days post-exposure, were assessed by (i) histopathology (Haematoxylin/Eosin Staining), (ii) characterization of apoptotic features by TUNEL staining. Data were compared with those obtained by CdCl2 (400?g/rat), SiNPs (600?g/rat), 0.1 ml saline. Area-specific cell apoptosis was observed in all treatment groups: cortex and inner medulla were the most affected regions. Apoptotic changes were apparent at 7 days post-exposure in both areas, and were still observable in inner medulla 30 days after treatment. Increase in apoptotic frequency was more pronounced in Cd-SiNP-treated animals compared to either CdCl2 or SiNPs. Histological findings showed comparable alterations in the renal glomerular (cortex) architecture occurring in all treatment groups at both time-points considered. The glomeruli appeared often collapsed, showing condensed, packed mesangial and endothelial cells. Oedematous haemorrhagic glomeruli were also observed in Cd-SiNPs-treated animals. Bare SiNPs caused morphological and apoptotic changes without modifying the renal gene expression profile. These findings support the concept that multiple assays and an integrated testing strategy should be recommended to characterize toxicological responses to nanoparticles in mammalian systems.

Coccini, T.; Roda, E.; Barni, S.; Manzo, L.

2013-04-01

34

Morphological Changes of Myelin Sheaths in Rats Intracranially Injected with Apotransferrin  

Microsoft Academic Search

Previous findings from our laboratories indicate that the intracranial injection of apotransferrin (aTf) in neonatal rats produces an accelerated oligodendrocyte maturation and an enhanced production and deposition of myelin membranes in the brain. To evaluate the anatomical distribution and the morphological characteristics of the myelin in these rats, we analyzed the optic nerves, cerebellum, and selected areas of brain sections

Cecilia B. Marta; Pablo Paez; Margarita Lopez; Amanda Pellegrino de Iraldi; Eduardo F. Soto; Juana M. Pasquini

2003-01-01

35

Mild, Short-term Stress Alters Dendritic Morphology in Rat Medial Prefrontal Cortex  

E-print Network

., 2000) in rats. Finally, chronic administration of stress levels of cortisol has been shown to impairMild, Short-term Stress Alters Dendritic Morphology in Rat Medial Prefrontal Cortex Sarah M. Brown1 is a target for glucocorticoids, shows neurochem- ical changes in response to stress and mediates many

Wellman, Cara

36

Morphological evidence for local microcircuits in rat vestibular maculae  

NASA Technical Reports Server (NTRS)

Previous studies suggested that intramacular, unmyelinated segments of vestibular afferent nerve fibers and their large afferent endings (calyces) on type I hair cells branch. Many of the branches (processes) contain vesicles and are presynaptic to type II hair cells, other processes, intramacular nerve fibers, and calyces. This study used serial section transmission electron microscopy and three-dimensional reconstruction methods to document the origins and distributions of presynaptic processes of afferents in the medial part of the adult rat utricular macula. The ultrastructural research focused on presynaptic processes whose origin and termination could be observed in a single micrograph. Results showed that calyces had 1) vesiculated, spine-like processes that invaginated type I cells and 2) other, elongate processes that ended on type II cells pre- as well as postsynaptically. Intramacular, unmyelinated segments of afferent nerve fibers gave origin to branches that were presynaptic to type II cells, calyces, calyceal processes, and other nerve fibers in the macula. Synapses with type II cells occurred opposite subsynaptic cisternae (C synapses); all other synapses were asymmetric. Vesicles were pleomorphic but were differentially distributed according to process origin. Small, clear-centered vesicles, approximately 40-60 nm in diameter, predominated in processes originating from afferent nerve fibers and basal parts of calyces. Larger vesicles approximately 70-120 nm in diameter having approximately 40-80 nm electron-opaque cores were dominant in processes originating from the necks of calyces. Results are interpreted to indicate the existence of a complex system of intrinsic feedforward (postsynaptic)-feedback (presynaptic) connections in a network of direct and local microcircuits. The morphological findings support the concept that maculae dynamically preprocess linear acceleratory information before its transmission to the central nervous system.

Ross, M. D.

1997-01-01

37

A Biochemical and Morphological Study of Rat Liver Microsomes  

Microsoft Academic Search

Microsomes isolated by differential centrifugation from a rat liver homogenate in 0.88 ~t sucrose solution have been studied from the biochemical and morpho- logical point of view. 1. Under these experimental conditions, the \\

Y. Moule; C. ROUILLER; J. CHAUVEAU

1960-01-01

38

Blue maize: morphology and starch synthase characterization of starch granule.  

PubMed

The use of pigmented maize varieties has increased due to their high anthocyanins content, but very few studies are reported about the starch properties of these grains. The aim of this work was to isolate the starch granules from pigmented blue maize and carry out the morphological, physicochemical, and biochemical characterization studies. The proximate composition of starch granules showed high protein contents, after purification, the blue maize starch presented lower protein amount than starch from white maize (control). Although the purity of starch granules was increased, the damaged starch (determined for the Maltase cross absence) was also increased. Scanning electron microscopy showed the presence of some pores and channels in the blue maize starch. The electrophoretic protein profiles showed differences in the bands that correspond to the enzymes involved in the starch biosynthesis; these differences could explain the variation in morphological characteristics of blue maize starches against starch from white maize. PMID:19153833

Utrilla-Coello, Rubi G; Agama-Acevedo, Edith; de la Rosa, Ana Paulina Barba; Martinez-Salgado, Jose L; Rodriguez-Ambriz, Sandra L; Bello-Perez, Luis A

2009-03-01

39

Effects of phenytoin on morphology and structure of hippocampal CA3 pyramidal neurons of rats in chronic stress  

Microsoft Academic Search

AIM: To investigate the effects of phenytoin (DPH) on morphological and structural changes of pyramidal neurons in hippocampal CA3 of rats induced by chronic stress. METHODS: Using Nissl staining, Golgi staining, and electron microscope, the morphology and structure of pyramidal neurons in hippocampal CA3 of rats were observed. RESULTS: Chronic stress resulted in loss of hippocampal CA3 pyramidal neuron from

ZHANG Yan-Mei; YANG Quan; XU Chong-Tao; LI Kang-Sheng; LI Wei-Qiu

2003-01-01

40

Crack layer morphology and toughness characterization in steels  

NASA Technical Reports Server (NTRS)

Both the macro studies of crack layer propagation are presented. The crack extension resistance parameter R sub 1 based on the morphological study of microdefects is introduced. Experimental study of the history dependent nature of G sub c supports the representation of G sub c as a product of specific enthalpy of damage (material constant) and R sub 1. The latter accounts for the history dependence. The observation of nonmonotonic crack growth under monotonic changes of J as well as statistical features of the critical energy release rate (variance of G sub c) indicate the validity of the proposed damage characterization.

Chudnovsky, A.; Bessendorf, M.

1983-01-01

41

Synthesis and morphology characterization of polydimethylsiloxane-containing block copolymers  

NASA Astrophysics Data System (ADS)

The thin film morphology characteristics of polydimethylsiloxane-containing block copolymers have been investigated. For this investigation, a commercially available hydroxyl terminated PDMS was purchased from Gelest and attached to a carboxylic acid functional reversible addition-fragmentation chain transfer (RAFT) agent by Steglich esterification. This produced macro-RAFT agents to which styrene monomer was polymerized. By using this approach the generation of low polydispersity polystyrene-block-polydimethylsiloxane (PS-block-PDMS) copolymers of various molecular weights spanning a wide volume fraction range in which the PDMS block remained the same in each polymerization. Synthesized block copolymers were characterized by gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR) spectroscopy. Bulk and thin film characterization of PS-block-PDMS copolymers was done by small-angle x-ray scattering (SAXS), transmission electron microscopy (TEM), contact angle measurements, scanning force microscopy (SFM), and grazing incidence small-angle X-ray scattering (GISAXS). The following observations have been made. For PS-rich PS-block -PDMS copolymer thin films the low surface tension of PDMS caused it to migrate to the film surface regardless of solvent choice. The surface morphology was found to depend strongly on the solubility parameter of the solvent and exhibited SFM images consistent with parallel cylinder, perforated lamellar, and lamellar surface layers with increasing solvent solubility parameter. This behavior was due to the selective swelling of the individual blocks under slightly selective, good solvent conditions. A custom solvent annealing apparatus provided similar results in which order-order transitions in the thin films were observed with increasing solvent solubility parameter. Additionally improvements in the long-range order were observed after 1 h of solvent annealing. PS-rich PS-block-PDMS copolymer thin films also displayed PDMS rich surfaces after casting. Etching of this wetting layer by exposure to ultraviolet/ozone (UVO) cleaner allowed characterization of the interior film morphology. GISAXS was also able to characterize domain orientation in the as-cast and selectively etched thin films. PDMS cylinder orientation in PS-block-PDMS copolymer was found to be dependent on solvent choice and polymer molecular weight. The likely mechanism for perpendicularly oriented PDMS cylinders in selective solvents was an order-order transition to spheres where cylinders would nucleate at the air/film surface and template a perpendicularly oriented morphology during evaporation induced ordering. Perpendicularly oriented PDMS cylinders were observed in the lower molecular weight PS-rich PS- block-PDMS thin film samples indicating a preferential molecular weight range for the formation of perpendicular domains. Solvent annealing in PS selective chlorobenzene improved the long range order, but was not a strong driving force in altering domain orientation.

Wadley, Maurice

42

Quercetin induces morphological and proliferative changes of rat’s uteri under estrogen and progesterone influences  

PubMed Central

This study investigated the effect of 10 or 100 mg/kg/day quercetin on the uterus of ovariectomized adult female rats receiving sex-steroid replacement regime mimicking changes in hormonal profiles during the reproductive cycle. Following seven days of treatment with estrogen and progesterone with or without quercetin, uteri were harvested for histological and proliferative cell nuclear antigen (PCNA) protein and mRNA expression and PCNA protein distribution analyses. Our findings indicated that co-administration of 10 mg/kg/day quercetin with estrogen and progesterone caused a significant decrease in the size of uterine lumen and epithelial heights with lower PCNA protein and mRNA expression as compared to estrogen plus progesterone-only treatment (P < 0.05). Concomitant treatment with estrogen and progesterone with 100 mg/kg/day quercetin resulted in a marked increase in the number of glands with increased PCNA protein and mRNA expression. Significantly higher PCNA distribution was observed in the stroma and glands as compared to estrogen plus progesterone-only treatment (P < 0.05). In conclusion, at 10 mg/kg/day, quercetin affects uterine morphology but not proliferation, however at 100 mg/kg/day, quercetin induced significant stromal and glandular proliferation which could predispose the uterus towards neoplastic development. PMID:25337190

Shahzad, Huma; Giribabu, Nelli; Muniandy, Sekaran; Salleh, Naguib

2014-01-01

43

Aircraft noise exposure affects rat behavior, plasma norepinephrine levels, and cell morphology of the temporal lobe*  

PubMed Central

In order to investigate the physiological effects of airport noise exposure on organisms, in this study, we exposed Sprague-Dawley rats in soundproof chambers to previously recorded aircraft-related noise for 65 d. For comparison, we also used unexposed control rats. Noise was arranged according to aircraft flight schedules and was adjusted to its weighted equivalent continuous perceived noise levels (L WECPN) of 75 and 80 dB for the two experimental groups. We examined rat behaviors through an open field test and measured the concentrations of plasma norepinephrine (NE) by high performance liquid chromatography-fluorimetric detection (HPLC-FLD). We also examined the morphologies of neurons and synapses in the temporal lobe by transmission electron microscopy (TEM). Our results showed that rats exposed to airport noise of 80 dB had significantly lower line crossing number (P<0.05) and significantly longer center area duration (P<0.05) than control animals. After 29 d of airport noise exposure, the concentration of plasma NE of exposed rats was significantly higher than that of the control group (P<0.05). We also determined that the neuron and synapsis of the temporal lobe of rats showed signs of damage after aircraft noise of 80 dB exposure for 65 d. In conclusion, exposing rats to long-term aircraft noise affects their behaviors, plasma NE levels, and cell morphology of the temporal lobe. PMID:22135145

Di, Guo-qing; Zhou, Bing; Li, Zheng-guang; Lin, Qi-li

2011-01-01

44

Characterization of ocular gland morphology and tear composition of pinnipeds  

PubMed Central

Objective The importance of tear film integrity to ocular health in terrestrial mammals is well established, however, in marine mammals, the role of the tear film in protection of the ocular surface is not known. In an effort to better understand the function of tears in maintaining health of the marine mammal eye surface, we examined ocular glands of the California sea lion, and began to characterize the biochemical nature of the tear film of pinnipeds. Procedures Glands dissected from California sea lion eyelids and adnexa were examined for gross morphology, sectioned for microscopic analysis, and stained with haematoxylin and eosin. The tear film was examined using interferometry. Tears were collected from humans and pinnipeds for analysis of protein and carbohydrate content. Results The sea lion has sebaceous glands in the lid, but these glands are different in size and orientation compared to typical meibomian glands of terrestrial mammals. Two other accessory ocular glands located dorsotemporally and medially appeared to be identical in morphology, with tubulo-acinar morphology. An outer lipid layer on the ocular surface of the sea lion was not detected using interferometry, consistent with the absence of typical meibomian glands. Similar to human tears, the tears of pinnipeds contain several proteins but the ratio of carbohydrate to protein was greater than that in human tears. Conclusions Our findings indicate that the ocular gland architecture and biochemical nature of the tear film of pinnipeds have evolved to adapt to the challenges of an aquatic environment. PMID:23067374

Davis, Robin Kelleher; Doane, Marshall G.; Knop, Erich; Knop, Nadja; Dubielzig, Richard R.; Colitz, Carmen M. H.; Argüeso, Pablo; Sullivan, David A.

2012-01-01

45

Juvenile and adult rat neuromuscular junctions: density, distribution, and morphology.  

PubMed

Anatomical and physiological differences in neuromuscular junctions (NMJs) between juvenile and adult muscle may partially explain the variability in clinical results following chemodenervation with botulinum toxin or nerve repair in children and adults. We evaluated NMJ density, distribution, and morphometry in biceps brachii and gastrocnemius muscles from juvenile and adult rats. Motor endplates were stained with Karnovsky-Roots methods, and NMJ density (number/gram muscle tissue) was determined. The NMJ morphometry was quantitated with alpha-bungarotoxin labeling using confocal microscopy. Juvenile rats had a greater NMJ density in both muscles compared with adult rats. Juveniles and adult rats had a similar NMJ distribution in both muscles. In juvenile muscles NMJs occupied approximately 50% of the surface area and 70% of the length, width, circumference, and gutter depth compared with adult muscles. Our study demonstrates that although NMJs are smaller, juvenile muscles have a higher NMJ density than do adult muscles with similar distributions. If these age-dependent differences in NMJ density are obtained in humans, they may account, at least in part, for the better recovery that occurs in children than adults after nerve repair and also suggest that the dosage of botulinum toxin (units per kg) for chemodenervation may need to be increased in juveniles. PMID:12451605

Ma, Jianjun; Smith, Beth P; Smith, Thomas L; Walker, Francis O; Rosencrance, Eileen V; Koman, L Andrew

2002-12-01

46

Morphological, Host Range, and Genetic Characterization of Two Coliphages  

PubMed Central

Two coliphages, AR1 and LG1, were characterized based on their morphological, host range, and genetic properties. Transmission electron microscopy showed that both phages belonged to the Myoviridae; phage particles of LG1 were smaller than those of AR1 and had an isometric head 68 nm in diameter and a complex contractile tail 111 nm in length. Transmission electron micrographs of AR1 showed phage particles consisting of an elongated isometric head of 103 by 74 nm and a complex contractile tail 116 nm in length. Both phages were extensively tested on many strains of Escherichia coli and other enterobacteria. The results showed that both phages could infect many serotypes of E. coli. Among the enterobacteria, Proteus mirabilis, Shigella dysenteriae, and two Salmonella strains were lysed by the phages. The genetic material of AR1 and LG1 was characterized. Phage LG1 had a genome size of 49.5 kb compared to 150 kb for AR1. Restriction endonuclease analysis showed that several restriction enzymes could degrade DNA from both phages. The morphological, genome size, and restriction endonuclease similarities between AR1 and phage T4 were striking. Southern hybridizations showed that AR1 and T4 are genetically related. The wide host ranges of phages AR1 and LG1 suggest that they may be useful as biocontrol, therapeutic, or diagnostic agents to control and detect the prevalence of E. coli in animals and food. PMID:12957924

Goodridge, Lawrence; Gallaccio, Alicia; Griffiths, Mansel W.

2003-01-01

47

Morphological Characterization of the Polyflux 210H Hemodialysis Filter Pores  

PubMed Central

Background. Morphological characterization of hemodialysis membranes is necessary to improve pore design. Aim. To delineate membrane pore structure of a high flux filter, Polyflux 210H. Methods. We used a Joel JSM-6010LV scanning electron microscope (SEM) and a SU6600 Hitachi field emission scanning electron microscope (FESEM) to characterize the pore and fiber morphology. The maximal diameters of selected uremic toxins were calculated using the macromolecular modeling Crystallographic Object-Oriented Toolkit (COOT) software. Results. The mean pore densities on the outermost and innermost surfaces of the membrane were 36.81% and 5.45%, respectively. The membrane exhibited a tortuous structure with poor connection between the inner and outer pores. The aperture's width in the inner surface ranged between 34 and 45?nm, which is 8.76–11.60 times larger than the estimated maximum diameter of ?2-microglobulin (3.88?nm). Conclusion. The results suggest that the diameter size of inner pore apertures is not a limiting factor to middle molecules clearance, the extremely diminished density is. Increasing inner pore density and improving channel structure are strategies to improve clearance of middle molecules. PMID:23209902

Hedayat, A.; Szpunar, J.; Kumar, N. A. P. Kiran; Peace, R.; Elmoselhi, H.; Shoker, A.

2012-01-01

48

Characterization of Leptospira infection in suckling and weaning rat pups.  

PubMed

Rats are known to be the most important reservoirs of Leptospira spp. However, the leptospiral dose and age at which rats become resistant to Leptospira infection are not yet well elucidated. Aimed to characterize leptospirosis in rat pups, we found that suckling pups (4-, 7-, and 14-day old) are susceptible to leptospires and resistance starts from the weaning age (23-day old). Susceptibility of rat pups was also affected by the infecting dose of the organisms. Jaundice, decrease in body weight, and neurological symptoms prior to moribundity was evident in infected suckling pups. However, 23-day-old infected pups did not manifest any pathological changes and were able to survive the infection similar to adult rats. Based on these results, we propose the suckling rat pup as a novel animal model of human leptospirosis to investigate pathogenesis, development of host resistance, and the mechanisms involved in rats becoming maintenance hosts for leptospires. PMID:25605653

Muslich, Lisa Tenriesa; Villanueva, Sharon Y A M; Amran, Muhammad Yunus; Segawa, Takaya; Saito, Mitsumasa; Yoshida, Shin-Ichi

2015-02-01

49

A morphological study of the circadian cycle of the pineal gland of the rat  

Microsoft Academic Search

To seek a morphological expression of circadian rhythm, we investigated cytologically pineal glands taken from rats every 2 to 4 h under a lighting regime of 12 h of illumination (6:00 to 18:00) and 12 h of darkness. The changes in the number of synaptic ribbons and ribbon fields was observed by electron microscopy. The number of these intracellular elements

Katsumaro Kurumado; Wataru Mori

1977-01-01

50

Combined effect of weightlessness and ionizing radiation on rats (results of morphological studies)  

Microsoft Academic Search

We submit the results of morphological studies conducted on rats exposed to radiation on Kosmos-690 satellite, in order to demonstrate the distinctions of the combined effect of weightlessness and penetrating radiation. Analysis of the changes demonstrated was made in three main directions: how weightlessness affects the course of radiation lesions; how radiation affects changes caused by weightlessness; summation of effects

V. V. Portugalov; E. A. Savina

1978-01-01

51

The effect of extracellular calcium elevation on morphology and function of isolated rat osteoclasts  

Microsoft Academic Search

Osteoclasts are large multinucleate cells unique in their capacity to resorb bone. These cells are exposed locally to high levels of ionised calcium during the process of resorption. We have therefore examined the effect of elevated extracellular calcium on the morphology and function of freshly disaggregated rat osteoclasts. Cell size and motility were quantitated by time-lapse video recording together with

Harish K. Datta; Iain MacIntyre; Mone Zaidi

1989-01-01

52

Morphological consequences of early reperfusion following thrombotic or mechanical occlusion of the rat middle cerebral artery  

Microsoft Academic Search

The early morphological consequences of recirculation following middle cerebral artery (MCA) occlusion were studied in two rat models. The proximal MCA was occluded for 1 h by either a surgical clip or platelet thrombus; subsequently, 1 h of recirculation was facilitated. Following clip occlusion and recirculation, mild astrocytic swelling, especially around blood vessels, was detected in reperfused cortical and striatal

W. D. Dietrich; H. Nakayama; B. D. Watson; H. Kanemitsu

1989-01-01

53

Tualang honey supplement improves memory performance and hippocampal morphology in stressed ovariectomized rats.  

PubMed

Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed sham-operated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17?-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rats. PMID:23810156

Al-Rahbi, Badriya; Zakaria, Rahimah; Othman, Zahiruddin; Hassan, Asma; Mohd Ismail, Zul Izhar; Muthuraju, Sangu

2014-01-01

54

Morphological Development of Thick-Tufted Layer V Pyramidal Cells in the Rat Somatosensory Cortex  

PubMed Central

The thick-tufted layer V pyramidal (TTL5) neuron is a key neuron providing output from the neocortex. Although it has been extensively studied, principles governing its dendritic and axonal arborization during development are still not fully quantified. Using 3-D model neurons reconstructed from biocytin-labeled cells in the rat somatosensory cortex, this study provides a detailed morphological analysis of TTL5 cells at postnatal day (P) 7, 14, 21, 36, and 60. Three developmental periods were revealed, which were characterized by distinct growing rates and properties of alterations in different compartments. From P7 to P14, almost all compartments grew fast, and filopodia-like segments along apical dendrite disappeared; From P14 to P21, the growth was localized on specified segments of each compartment, and the densities of spines and boutons were significantly increased; From P21 to P60, the number of basal dendritic segments was significantly increased at specified branch orders, and some basal and oblique dendritic segments were lengthened or thickened. Development changes were therefore seen in two modes: the fast overall growth during the first period and the slow localized growth (thickening mainly on intermediates or lengthening mainly on terminals) at the subsequent stages. The lengthening may be accompanied by the retraction on different segments. These results reveal a differential regulation in the arborization of neuronal compartments during development, supporting the notion of functional compartmental development. This quantification provides new insight into the potential value of the TTL5 morphology for information processing, and for other purposes as well. PMID:21369363

Romand, Sandrine; Wang, Yun; Toledo-Rodriguez, Maria; Markram, Henry

2011-01-01

55

Morphological and functional heterogeneity in the rat prostatic gland.  

PubMed

Ductal morphogenesis and adult ductal branching patterns were examined in the rat prostate by a microdissection method. The rat prostate consists of paired (right and left) subdivisions which correspond in large part to the classically defined lobes: ventral prostate, lateral prostate, dorsal prostate, and coagulating gland. Of particular interest was the finding that the lateral prostate consists of two different ductal zones: (1) lateral type 1 prostate with 5-7 long main ducts (resembling miniature palm trees) that extend cranially towards both the seminal vesicle and dorsal prostate to arborize near the bladder neck, and (2) lateral type 2 prostate with 5-6 short main ducts that arborize caudal to the bladder neck and give rise to compact bushy glands. Both lateral prostatic groups had a ductal-acinar organization. The adult structure of the other rat prostatic lobes was also examined, and closely resembled their mouse counterparts. The ventral prostate, which had 2-3 pairs of slender main ducts per side, and the coagulating gland, which had 1 main duct per side, was completely ductal in structure. In contrast, the dorsal prostate, which had 5-6 pairs of main ducts per side, had a ductal-acinar structure. Ductal branching morphogenesis occurred at different rates in different lobes and was essentially complete in the prostate at the 30 days. Immunocytochemical studies with an antibody to DP-1, a major secretory protein of the rat dorsal prostate, revealed that secretory function was initiated at approximately 30 days after birth in the coagulating gland, the dorsal prostate, and lateral type 1 prostate. A consistent feature of the lateral type 2 prostate was the absence of DP-1. On Western blots, DP-1 was detected in the secretion of the coagulating gland, lateral type 1 and dorsal prostate, but not in the ventral and lateral type 2 prostate. Polyacrylamide gel electrophoresis confirmed this result and demonstrated that the lateral type 2 prostate expressed several low-molecular weight secretory proteins not found in the other lobes of the prostate. On the whole, the rat prostate exhibited considerable heterogeneity both between and within lobes in developmental processes, ductal patterning, histology, and functional expression. PMID:1786296

Hayashi, N; Sugimura, Y; Kawamura, J; Donjacour, A A; Cunha, G R

1991-08-01

56

Isolation and characterization of fly ash from rat lung tissue  

Microsoft Academic Search

Inhaled fly ash may be leached by lung fluids, making potentially toxic trace elements in the fly ash bioavailable. We studied the composition and morphology of fly ash particles recovered from lungs of rats exposed to fly ash from a power plant burning pulverized eastern coal. Animals were sacrificed 1, 3, 6, and 12 mo after the commencement of the

S. J. Rothenberg; F. A. Seiler; C. H. Hobbs; G. S. Casuccio; C. E. Spangler

1989-01-01

57

The morphology, number, distribution and central projections of Class I retinal ganglion cells in albino and hooded rats.  

PubMed

Class I retinal ganglion cells have been identified in wholemounts of rat retinae following injections of horseradish peroxidase (HRP) into retino-recipient nuclei. Class I cells are characterized by relatively large somata, 3-7 fairly frequently branching large-gauge primary dendrites and relatively thick axons. Cells with a very similar morphology have been visualized in the ganglion cell layer of retinal wholemounts using a neurofibrillar stain. The size of the somata and dendritic trees of Class I cells is affected by the density of all classes of ganglion cells: both somata and dendritic trees of Class I cells located in the region of peak density are smaller than those located in medium- and low-density ganglion cell regions. The mean numbers of Class I ganglion cells labelled following massive injections of HRP into retino-recipient nuclei were 876 (in albino rats) and 944 (in hooded rats), while the mean number of cells stained with the neurofibrillar method in albino retinae was 791. Thus, with the total number of positively identified retinal ganglion cells being 110,000-115,000 [Potts et al., 1982; Perry et al., 1983], Class I cells in both strains of rat constitute less than 1% of all retinal ganglion cells. Nevertheless the dendritic fields of Class I cells cover the entire retina. Although Class I cells are distributed relatively evenly across the retina, the density is slightly greater in the lower temporal retina where the bulk of the ipsilaterally projecting fibres originates. While Class I cells represent up to 10% of ipsilaterally projecting retinal ganglion cells in both strains of rat, fewer Class I cells project ipsilaterally in albinos than in hooded rats. All contralaterally projecting Class I cells appear to send branching axons to the superior colliculus and dorsal lateral geniculate nucleus. Class I cells represent a larger proportion of the ganglion cells projecting to the dorsal lateral geniculate nucleus (4-5%) than that of ganglion cells projecting to the superior colliculus (about 1%). The morphology, numbers, distribution and the pattern of the central projections of Class I retinal ganglion cells in rats suggest that they are likely to be homologues of the alpha-type ganglion cells distinguished in carnivores. PMID:3902145

Dreher, B; Sefton, A J; Ni, S Y; Nisbett, G

1985-01-01

58

Spectroscopic and morphologic characterization of the dentin/adhesive interface  

NASA Astrophysics Data System (ADS)

The potential environmental risks associated with dental amalgams have forced many European countries to ban their use and turn to alternative materials, composite resins. The purpose of this study was to correlate morphologic characterization of the dentin/adhesive bond with chemical analyses using micro-FTIR and micro-Raman spectroscopy. A commercial dental adhesive was placed on dentin substrates cut from extracted, unerupted human third molars. Sections of the dentin/adhesive interface were investigated using IR radiation produced at the Aladdin synchrotron source; visible radiation from Kr+ laser was used for the micro-Raman spectroscopy and through the use of differentially staining in conjunction with light microscopy. Due to its limited spatial resolution and the unknown samples thickness the IR results cannot be used quantitatively in determining the extent of diffusion. The result from the micro-Raman spectroscopy and light microscopy indicate exposed protein at the dentin/adhesive interface. Using a laser that reduces background fluorescence, the micro-Raman spectroscopy provides quantitative chemical and morphologic information on the dentin/adhesive interface. The staining procedure is sensitive to sites of pure protein and complements the Raman results.

Lemor, R. M.; Kruger, Michael B.; Wieliczka, David M.; Swafford, Jim R.; Spencer, Paulette

1999-04-01

59

Spectroscopic and morphologic characterization of the dentin/adhesive interface  

NASA Astrophysics Data System (ADS)

The potential environmental risks associated with mercury release have forced many European countries to ban the use of dental amalgam. Alternative materials such as composite resins do not provide the clinical function for the length of time characteristically associated with dental amalgam. The weak link in the composite restoration is the dentin/adhesive bond. The purpose of this study was to correlate morphologic characterization of the dentin/adhesive bond with chemical analyses using micro- Fourier transform infrared and micro-Raman spectroscopy. A commercial dental adhesive was placed on dentin substrates cut from extracted, unerupted human third molars. Sections of the dentin/adhesive interface were investigated using infrared radiation produced at the Aladdin synchrotron source; visible radiation from a Kr+ laser was used for the micro-Raman spectroscopy. Sections of the dentin/adhesive interface, differentially stained to identify protein, mineral, and adhesive, were examined using light microscopy. Due to its limited spatial resolution and the unknown sample thickness the infrared results cannot be used quantitatively in determining the extent of diffusion. The results from the micro-Raman spectroscopy and light microscopy indicate exposed protein at the dentin/adhesive interface. Using a laser that reduces background fluorescence, the micro-Raman spectroscopy provides quantitative chemical and morphologic information on the dentin/adhesive interface. The staining procedure is sensitive to sites of pure protein and thus, complements the Raman results.

Lemor, R. M.; Kruger, Michael B.; Wieliczka, David M.; Swafford, Jim R.; Spencer, Paulette

1999-01-01

60

Detailed characterization of PBX morphology for mesoscale simulations  

NASA Astrophysics Data System (ADS)

Plastic-Bonded Explosives (PBXs) are composed of energetic grains embedded in a polymeric binder. The heterogeneity at this material scale serves to localize energy during deformation, determining damage and hot spot development leading to reaction. Accurate determination of PBX morphology is needed to characterize and understand these materials, and is essential input for mesoscale simulations. X-ray microtomography was used to determine the threedimensional x-ray cross-section of a mock explosive for which all formulation details are known. Specialized image processing routines were used to identify individual features (voids, grains, binder). Mass fractions, void content, and grain size statistics were compared with the formulation. The quantity of material needed to accurately represent the mesostructure in simulations, i.e. representative volume element size, was determined, as well as grain on grain contact density, which may correlate with sensitivity. Preliminary results from computations using these mesostructures will be reported.

Bardenhagen, Scott Gary; Luo, Huiyang; Armstrong, Ronald W.; Lu, Hongbing

2012-03-01

61

Detailed Characterization of PBX Morphology for Mesoscale Simulations  

NASA Astrophysics Data System (ADS)

Plastic-Bonded Explosives (PBXs) are composed of energetic grains embedded in a polymeric binder. The heterogeneity at this material scale serves to localize energy during deformation, determining damage and hot spot development leading to reaction. Accurate determination of PBX morphology is needed to characterize and understand these materials, and is essential input for mesoscale simulations. X-ray microtomography was used to determine the three-dimensional x-ray cross-section of a mock explosive for which all formulation details are known. Specialized image processing routines were used to identify individual features (voids, grains, binder). Mass fractions, void content, and grain size statistics were compared with the formulation. The quantity of material needed to accurately represent the mesostructure in simulations, i.e. representative volume element size, was determined, as well as grain on grain contact density, which may correlate with sensitivity. Preliminary results from computations using these mesostructures will be reported.

Bardenhagen, Scott; Luo, Huiyang; Lu, Hongbing; Armstrong, Ronald

2011-06-01

62

Morphological and optical characterization of polyelectrolyte multilayers incorporating nanocrystalline cellulose.  

PubMed

Aqueous layer-by-layer (LbL) processing was used to create polyelectrolyte multilayer (PEM) nanocomposites containing cellulose nanocrystals and poly(allylamine hydrochloride). Solution-dipping and spin-coating assembly methods gave smooth, stable, thin films. Morphology was studied by atomic force microscopy (AFM) and scanning electron microscopy (SEM), and film growth was characterized by X-ray photoelectron spectroscopy (XPS), ellipsometry, and optical reflectometry. Relatively few deposition cycles were needed to give full surface coverage, with film thicknesses ranging from 10 to 500 nm. Films prepared by spin-coating were substantially thicker than solution-dipped films and displayed radial orientation of the rod-shaped cellulose nanocrystals. The relationship between film color and thickness is discussed according to the principles of thin film interference and indicates that the iridescent properties of the films can be easily tailored in this system. PMID:16961313

Cranston, Emily D; Gray, Derek G

2006-09-01

63

Morphological and physiological properties of the A17 amacrine cell of the rat retina.  

PubMed

In addition to the well-studied AII amacrine cell, there is another amacrine cell type participating in the rod pathway of the mammalian retina. In cat, this cell is called the A17 amacrine cell, and in rabbits, it is called the indoleamine-accumulating amacrine cell (S1 and S2); however, the presence of the corresponding cell type has not yet been described in detail for the rat retina. To this end, we injected amacrine cells with Neurobiotin in vertical retinal slices. After histological processing, we were able to reconstruct the morphology of a wide-field amacrine cell which showed characteristics of A17 and S1/S2 amacrine cells. The rat wide-field amacrine cells exhibited the same stratification pattern, their dendrites bore varicosities and ramified in sublamina 5 of the inner plexiform layer (IPL), and they were dye-coupled to other amacrine cells. To determine whether those amacrine cells shared electrophysiological characteristics as well, we performed whole-cell patch-clamp recordings and examined their voltage-activated currents and neurotransmitter-induced currents. We never observed voltage-gated Na+ currents and spike-like potentials upon depolarization by current injection in these cells. We identified GABA- and glycine-sensitive Cl- currents that could be blocked by bicuculline and strychnine, respectively. We also observed kainate- and AMPA-activated currents, which could be inhibited by the application of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). Finally, a 400-ms full-field light stimulus was used to characterize the light responses of A17 amacrine cells. The light ON-induced inward current could be suppressed by the application of 2,3-Dioxo-6-nitro-1,2,3,4-tetrahydrobenzo[f]quinoxaline-7-sulphonamide (NBQX), while the majority of the light OFF-induced current was inhibited by bicuculline and reduced to a smaller extent by NBQX. CPP, an NMDA blocker, had no effect on the light response of rat A17 amacrine cells. PMID:11153656

Menger, N; Wässle, H

2000-01-01

64

Morphological and functional reorganization of rat medial prefrontal cortex in neuropathic pain  

PubMed Central

Neuropathic pain is a chronic pain that results from lesion or dysfunction of the nervous system. Depression and cognitive decline are often coupled to chronic pain, suggesting the involvement of cortical areas associated with higher cognitive functions. We investigated layer 2/3 pyramidal neurons in acute slices of the contralateral medial prefrontal cortex (mPFC) in the rat spared nerve injury (SNI) model of neuropathic pain and found morphological and functional differences between the mPFC of SNI and sham-operated animals. Basal, but not apical, dendrites of neurons from SNI rats are longer and have more branches than their counterparts in sham-operated animals; spine density is also selectively increased in basal dendrites of neurons from SNI rats; the morphological changes are accompanied by increased contribution to synaptic currents of the NMDA component. Interestingly, the NMDA/AMPA ratio of the synaptic current elicited in mPFC neurons by afferent fiber stimulation shows linear correlation with the rats' tactile threshold in the injured (but not in the contralateral) paw. Our results not only provide evidence that neuropathic pain leads to rearrangement of the mPFC, which may help defining the cellular basis for cognitive impairments associated with chronic pain, but also show pain-associated morphological changes in the cortex at single neuron level. PMID:19171885

Metz, Alexia E.; Yau, Hau-Jie; Centeno, Maria Virginia; Apkarian, A. Vania; Martina, Marco

2009-01-01

65

Morphological and biochemical assessment of the liver response to excess dietary copper in Fischer 344 rats.  

PubMed Central

The aim of this study was to determine the amount of excess dietary copper (Cu) necessary to experimentally induce liver lesions characteristic of Cu-associated disease in Fischer 344 rats. Male weanling Fischer 344 rats of uniform age were divided into 6 groups (n = 5) and fed a rodent diet containing 18 (control), 750, 1000, 1250, 1500, and 2000 microg/g Cu added as CuSO4. Rats were euthanized after 3 months on the experimental diets and their livers processed for histology, histochemistry, Cu analysis (by atomic absorption spectrophotometry), and quantification of malondialdehyde (MDA) by the thiobarbituric acid reaction. Hepatic Cu levels were significantly higher (P < 0.01) in rats receiving over 1000 microg/g Cu compared to the controls (means for each diet: control = 4.8 microg/g, 750 microg/g Cu = 39.6 microg/g, 1000 microg/g Cu = 111.2 microg/g, 1250 microg/g Cu = 389 microg/g, 1500 microg/g Cu = 509.4 microg/g, and 2000 microg/g Cu = 766 microg/g). Histological lesions increased gradually according to the level of dietary Cu. Significant morphologic changes (necrosis, portal inflammation, hyaline remnants) and reduced growth rate occurred in rats receiving over 1250 microg/g Cu. However, no significant differences were found for MDA levels between groups. The present study demonstrates that compared to other species, very high levels of excess dietary Cu are needed to induce significant liver injury in Fischer 344 rats. Increased MDA content was not detected in rats with morphologic evidence of liver damage, suggesting that lipid peroxidation may not play a major role in this model of Cu toxicity. Images Figure 2. Figure 3. Figure 4. PMID:11346262

Aburto, E M; Cribb, A E; Fuentealba, I C; Ikede, B O; Kibenge, F S; Markham, F

2001-01-01

66

Characterization of Inducible Cyclooxygenase in Rat Brain  

PubMed Central

Considerable debate exists regarding the cellular source of prostaglandins in the mammalian central nervous system (CNS). At least two forms of prostaglandin endoperoxide synthase, or cyclooxygenase (COX), the principal enzyme in the biosynthesis of these mediators, are known to exist. Both forms have been identified in the CNS, but only the distribution of COX 1 has been mapped in detail. In this study, we used Western blot analysis and immunohistochemistry to describe the biochemical characterization and anatomical distribution of the second, mitogen-inducible form of this enzyme, COX 2 in the rat brain. COX 2-like immunoreactive (COX 2-ir) staining occurred in dendrites and cell bodies of neurons, structures that are typically postsynaptic. It was noted in distinct portions of specific cortical laminae and subcortical nuclei. The distribution in the CNS was quite different from COX 1. COX 2-ir neurons were primarily observed in the cortex and allocortical structures, such as the hippocampal formation and amygdala. Within the amygdala, neurons were primarily observed in the caudal and posterior part of the deep and cortical nuclei. In the diencephalon, COX 2-ir cells were also observed in the paraventricular nucleus of the hypothalamus and in the nuclei of the anteroventral region surrounding the third ventricle, including the vascular organ of the lamina terminalis. COX 2-ir neurons were also observed in the subparafascicular nucleus, the medial zona incerta, and pretectal area. In the brainstem, COX 2-ir neurons were observed in the dorsal raphe nucleus, the nucleus of the brachium of the inferior colliculus, and in the region of the subcoeruleus. The distribution of COX 2-ir neurons in the CNS suggests that COX 2 may be involved in processing and integration of visceral and special sensory input and in elaboration of the autonomic, endocrine, and behavioral responses. PMID:7608344

BREDER, CHRISTOPHER D.; DEWITT, DAVID; KRAIG, RICHARD P.

2009-01-01

67

Facet Model and Mathematical Morphology for Surface Characterization  

SciTech Connect

This paper describes an algorithm for the automatic segmentation and representation of surface structures and non-uniformities in an industrial setting. The automatic image processing and analysis algorithm is developed as part of a complete on-line web characterization system of a papermaking process at the wet end. The goal is to: (1) link certain types of structures on the surface of the web to known machine parameter values, and (2) find the connection between detected structures at the beginning of the line and defects seen on the final product. Images of the pulp mixture (slurry), carried by a fast moving table, are obtained using a stroboscopic light and a CCD camera. This characterization algorithm succeeded where conventional contrast and edge detection techniques failed due to a poorly controlled environment. The images obtained have poor contrast and contain noise caused by a variety of sources. After a number of enhancement steps, conventional segmentation methods still f ailed to detect any structures and are consequently discarded. Techniques tried include the Canny edge detector, the Sobel, Roberts, and Prewitt's filters, as well as zero crossings. The facet model algorithm, is then applied to the images with various parameter settings and is found to be successful in detecting the various topographic characteristics of the surface of the slurry. Pertinent topographic elements are retained and a filtered image computed. Carefully tailored morphological operators are then applied to detect and segment regions of interest. Those regions are then selected according to their size, elongation, and orientation. Their bounding rectangles are computed and represented. Also addressed in this paper are aspects of the real time implementation of this algorithm for on-line use. The algorithm is tested on over 500 images of slurry and is found to segment and characterize nonuniformities on all 500 images.

Abidi, B.R.; Goddard, J.S.; Hunt, M.A.; Sari-Sarraf, H.

1999-11-13

68

Cerebral morphology and functional sparing after prenatal frontal cortex lesions in rats.  

PubMed

Rats were given suction lesions of the presumptive frontal cortex on embryonic day 18 (E18) and subsequently tested, as adults, on tests of spatial navigation (Morris water task, radial arm maze), motor tasks (Whishaw reaching task, beam walking), and locomotor activity. Frontal cortical lesions at E18 affected cerebral morphogenesis, producing unusual morphological structures including abnormal patches of neurons in the cortex and white matter as well as neuronal bridges between the hemispheres. A small sample of E18 operates also had hydrocephaly. The animals with E18 lesions without hydrocephalus were behaviorally indistinguishable from littermate controls. The results demonstrate that animals with focal lesions of the presumptive frontal cortex have gross abnormalities in cerebral morphology but the lesions leave the functions normally subserved by the frontal cortex in adult rats unaffected. The results are discussed in the context of a hypothesis regarding the optimal times for functional recovery from cortical injury. PMID:9578447

Kolb, B; Cioe, J; Muirhead, D

1998-03-01

69

Transplantation-induced functional/morphological changes in rat aorta allografts differ from those in arteries of rat kidney allografts.  

PubMed

The functional/morphological changes observed in rat aorta allografts were compared with those seen in the arteries of rat kidney allografts. Untreated allografts (F344-to-LEW) were collected at various times post-transplantation (Tx). Vascular smooth muscle cell (SMC) constriction to phenylephrine (Phe) and endothelial cell (EC)-dependent relaxation to acetylcholine (Ach) were assessed. Neointima formation in graft vessels was assessed by histology. In aorta allografts, the effects of Phe and Ach were irreversibly abolished within 3-2 weeks post-Tx. Neointima formation was consistently detected between 4 and 8 weeks post-Tx. In kidney allografts, sign of vasculopathy was seen in 10, 30 and 40% of resistance arteries at 8, 16 and 33 weeks post-Tx, respectively. In the main renal artery, substantial neointima formation was not apparent before 33 weeks post-Tx, the vasoconstrictor effect of Phe was fully maintained until then, and Ach-induced vasorelaxation was irreversibly reduced by approximately 70% from week 2 post-Tx onwards. These results indicate that the post-Tx functional/morphological changes seen in aorta allografts do not reflect those seen in arteries of kidney allografts. Hence, renal arteries from rat kidney allografts can be considered as a more relevant model to study the cascade of events leading to Tx-induced CGA in solid organ allografts. PMID:14974939

Andriambeloson, Emile; Cannet, Catherine; Pally, Charles; Klanke, Bernd; Bruns, Christian; Zerwes, Hans-Günter; Bigaud, Marc

2004-02-01

70

Low-Intensity physical activity beneficially alters the ultrastructural renal morphology of spontaneously hypertensive rats  

PubMed Central

INTRODUCTION AND OBJECTIVE: Kidney disorders can cause essential hypertension, which can subsequently cause renal disease. High blood pressure is also common among those with chronic kidney disease; moreover, it is a well-known risk factor for a more rapid progression to kidney failure. Because hypertension and kidney function are closely linked, the present study aimed to observe the beneficial effects of low-intensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats. METHOD: Male Wistar-Kyoto rats and spontaneously hypertensive rats were randomly allocated into four groups: sedentary or exercised Wistar-Kyoto and sedentary or exercised spontaneously hypertensive rats. The exercise lasted 20 weeks and consisted of treadmill training for 1 hour/day, 5 days/week. RESULTS: The exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26%. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity: (i) the interdigitations of the proximal and distal convoluted tubules; (ii) the basal membrane of the proximal and distal convoluted tubules; and (iii) in the basal membrane, slit diaphragm and pedicels of the glomerular filtration barrier. The spontaneously hypertensive rats also showed a decreased expression of connexin-43. CONCLUSION: Physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals. PMID:21789392

Garcia-Pinto, Angélica Beatriz; Soares de Matos, Verônica; Rocha, Vinicius; Moraes-Teixeira, Jéssica; Carvalho, Jorge José

2011-01-01

71

BIOCHEMICAL, FUNCTIONAL AND MORPHOLOGICAL INDICATORS OF NEUROTOXICITY: EFFECTS OF ACUTE ADMINISTRATION OF TRIMETHYLTIN TO THE DEVELOPING RAT  

EPA Science Inventory

The neurotoxic organometal, trimethyltin (TMT), was administered to rats on postnatal day (PND)5. Neurotoxicity was assessed throughout subsequent development using morphological, biochemical and functional endpoints. These consisted of brain weight measures and histology (morpho...

72

Morphological changes of gingiva in streptozotocin diabetic rats.  

PubMed

Gingivitis and periodontitis are chronic bacterial diseases of the underlying and surrounding tooth tissues. Diabetes mellitus is responsible for tooth deprivation both by decay and periodontal disease. The streptozotocin-induced diabetes results in a diabetic status in experimental animals similar to that observed in diabetes patients. The aim of the study was to investigate the relationship between the gingival lesions and the microangiopathy changes in streptozotocin-induced diabetes mellitus. Forty male Wistar rats were divided into two groups (control and experimental). Diabetes mellitus was induced by 45 mg/kg IV streptozotocin. The histological investigation of the marginal gingival and the relevant gingival papilla showed inflammation of the lamina propria and the squamous epithelium as well as marked thickness of the arteriole in the diabetic group, but no changes were observed in the control group. The results suggested a probable application of a routine gingival histological investigation in diabetic patients in order to control the progress of disease complications. It may be concluded that histological gingival investigation can be used as a routine assay for the control of the diabetic disease and prevention of its complications. PMID:20339569

Tesseromatis, C; Kotsiou, A; Parara, H; Vairaktaris, E; Tsamouri, M

2009-01-01

73

Morphological Changes of Gingiva in Streptozotocin Diabetic Rats  

PubMed Central

Gingivitis and periodontitis are chronic bacterial diseases of the underlying and surrounding tooth tissues. Diabetes mellitus is responsible for tooth deprivation both by decay and periodontal disease. The streptozotocin-induced diabetes results in a diabetic status in experimental animals similar to that observed in diabetes patients. The aim of the study was to investigate the relationship between the gingival lesions and the microangiopathy changes in streptozotocin-induced diabetes mellitus. Forty male Wistar rats were divided into two groups (control and experimental). Diabetes mellitus was induced by 45?mg/kg IV streptozotocin. The histological investigation of the marginal gingival and the relevant gingival papilla showed inflammation of the lamina propria and the squamous epithelium as well as marked thickness of the arteriole in the diabetic group, but no changes were observed in the control group. The results suggested a probable application of a routine gingival histological investigation in diabetic patients in order to control the progress of disease complications. It may be concluded that histological gingival investigation can be used as a routine assay for the control of the diabetic disease and prevention of its complications. PMID:20339569

Tesseromatis, C.; Kotsiou, A.; Parara, H.; Vairaktaris, E.; Tsamouri, M.

2009-01-01

74

Morphological and Receptorial Changes in the Epididymal Adipose Tissue of Rats Subjected to a Stressful Stimulus  

Microsoft Academic Search

Obesity is nowadays related to other pathological conditions such as inflammation, insulin resistance, and diabetes, but little is known about the relationship between psychological stress and adipocytes. We decided to study the expression of the translocator protein (TSPO) 18-kDa, peroxisome proliferator–activated receptor-? (PPAR-?), mitochondrial uncoupling protein-1 (UCP-1), and adipocyte morphology in the adipose tissue of rats subjected to stress conditions.

Enrico Campioli; Gianluca Carnevale; Rossella Avallone; Deanna Guerra; Mario Baraldi

2011-01-01

75

Architectural and morphological assessment of rat abdominal wall muscles: comparison for use as a human model.  

PubMed

The abdominal wall is a composite of muscles that are important for the mechanical stability of the spine and pelvis. Tremendous clinical attention is given to these muscles, yet little is known about how they function in isolation or how they interact with one another. Given the morphological, vascular, and innervation complexities associated with these muscles and their proximity to the internal organs, an appropriate animal model is important for understanding their physiological and mechanical significance during function. To determine the extent to which the rat abdominal wall resembles that of human, 10 adult male Sprague-Dawley rats were killed and formalin-fixed for architectural and morphological analyses of the four abdominal wall muscles (rectus abdominis, external oblique, internal oblique, and transversus abdominis). Physiological cross-sectional areas and optimal fascicle lengths demonstrated a pattern that was similar to human abdominal wall muscles. In addition, sarcomere lengths measured in the neutral spine posture were similar to human in their relation to optimal sarcomere length. These data indicate that the force-generating and length change capabilities of these muscles, relative to one another, are similar in rat and human. Finally, the fiber lines of action of each abdominal muscle were similar to human over most of the abdominal wall. The main exception was in the lower abdominal region (inferior to the pelvic crest), where the external oblique becomes aponeurotic in human but continues as muscle fibers into its pelvic insertion in the rat. We conclude that, based on the morphology and architecture of the abdominal wall muscles, the adult male Sprague-Dawley rat is a good candidate for a model representation of human, particularly in the middle and upper abdominal wall regions. PMID:20646108

Brown, Stephen H M; Banuelos, Karina; Ward, Samuel R; Lieber, Richard L

2010-09-01

76

Architectural and morphological assessment of rat abdominal wall muscles: comparison for use as a human model  

PubMed Central

The abdominal wall is a composite of muscles that are important for the mechanical stability of the spine and pelvis. Tremendous clinical attention is given to these muscles, yet little is known about how they function in isolation or how they interact with one another. Given the morphological, vascular, and innervation complexities associated with these muscles and their proximity to the internal organs, an appropriate animal model is important for understanding their physiological and mechanical significance during function. To determine the extent to which the rat abdominal wall resembles that of human, 10 adult male Sprague-Dawley rats were killed and formalin-fixed for architectural and morphological analyses of the four abdominal wall muscles (rectus abdominis, external oblique, internal oblique, and transversus abdominis). Physiological cross-sectional areas and optimal fascicle lengths demonstrated a pattern that was similar to human abdominal wall muscles. In addition, sarcomere lengths measured in the neutral spine posture were similar to human in their relation to optimal sarcomere length. These data indicate that the force-generating and length change capabilities of these muscles, relative to one another, are similar in rat and human. Finally, the fiber lines of action of each abdominal muscle were similar to human over most of the abdominal wall. The main exception was in the lower abdominal region (inferior to the pelvic crest), where the external oblique becomes aponeurotic in human but continues as muscle fibers into its pelvic insertion in the rat. We conclude that, based on the morphology and architecture of the abdominal wall muscles, the adult male Sprague-Dawley rat is a good candidate for a model representation of human, particularly in the middle and upper abdominal wall regions. PMID:20646108

Brown, Stephen H M; Banuelos, Karina; Ward, Samuel R; Lieber, Richard L

2010-01-01

77

Erythrocyte morphology and filterability in rats fed on diets containing different fats and oils.  

PubMed

The present study aimed to determine if the type of dietary fat or oil affects erythrocyte morphology and/or filterability in normal healthy rats. A feeding trial was carried out, in which nine groups of nine rats were fed on diets containing one of the following treatments (test fats or oils): anhydrous milk fat, anhydrous milk fat after passage through a column of active carbon, palm oil, MaxEPA fish oil, hydrogenated coconut oil, anhydrous tallow shortening, margarine hardstock, olive oil and soyabean oil. The test fats or oils supplemented with 10 g safflower-seed oil/kg were incorporated into otherwise nutritionally adequate diets so that the test fat or oil plus safflower-seed oil contributed 35% of the gross energy of the diet. The rats were fed for 10 weeks. Diet had a significant effect on five of the six classes of erythrocytes identified, and the proportion of cells in each class was shown to be dependent on diet. However, the attribute causing the dependence was not clear. There was no significant effect of diet on erythrocyte filterability index. There was no statistical correlation between erythrocyte filterability index and morphology. Although it has been observed that diet, particularly fish oil, can improve the filterability of erythrocytes once filterability is impaired, the effect of diet on erythrocyte filterability in normal healthy animals including humans is unclear. The importance of the differences in erythrocyte morphology due to diet is also unclear. Both areas deserve further investigation. PMID:8774223

Maccoll, A J; James, K A; Booth, C L

1996-07-01

78

Morphological characterization of dental prostheses interfaces using optical coherence tomography  

NASA Astrophysics Data System (ADS)

Fixed partial prostheses as integral ceramic, polymers, metal-ceramic or metal-polymers bridges are mainly used in the frontal part of the dental arch (especially the integral bridges). They have to satisfy high stress as well as esthetic requirements. The masticatory stress may induce fractures of the bridges. These may be triggered by initial materials defects or by alterations of the technological process. The fractures of these bridges lead to functional, esthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. Dental interfaces represent one of the most significant aspects in the strength of the dental prostheses under the masticatory load. The purpose of this study is to evaluate the capability of optical coherence tomography (OCT) to characterize the dental prostheses interfaces. The materials used were several fixed partial prostheses integral ceramic, polymers, metal-ceramic and metal-polymers bridges. It is important to produce both C-scans and B-scans of the defects in order to differentiate morphological aspects of the bridge infrastructures. The material defects observed with OCT were investigated with micro-CT in order to prove their existence and positions. In conclusion, it is important to have a non invasive method to investigate dental prostheses interfaces before the insertion of prostheses in the oral cavity.

Sinescu, Cosmin; Negrutiu, Meda L.; Ionita, Ciprian; Marsavina, Liviu; Negru, Radu; Caplescu, Cristiana; Bradu, Adrian; Topala, Florin; Rominu, Roxana O.; Petrescu, Emanuela; Leretter, Marius; Rominu, Mihai; Podoleanu, Adrian G.

2010-03-01

79

Genetic and morphological characterization of a Fusarium verticillioides conidiation mutant.  

PubMed

Enteroblastic phialidic conidiation by the corn pathogen Fusarium verticillioides (teleomorph Gibberella moniliformis) produces abundant, mostly single-celled microconidia in distinctive long chains. Because conidia might be critical for establishing in planta associations, we characterized a spontaneous F. verticillioides conidiation mutant in which phialides were incapable of enteroblastic conidiogenesis. Instead of producing a conidium, the phialide apex developed a determinate, slightly undulating, germ tube-like outgrowth, in which nuclei rarely were seen. Electron microscopy showed that the apical outgrowth possessed a thick, rough, highly fibrillar outer wall layer that was continuous with the thinner and smoother outer wall layer of the phialide. Both the inner wall layer and plasma membrane also were continuous between the apical outgrowth and phialide. The apical neck region of mutant phialides lacked both a thickened inner wall layer and a wall-building zone, which were critical for conidium initial formation. No indication of septum formation or separation of the apical outgrowth from mutant phialides was observed. These aberrations suggested the apical outgrowth was not a functional conidium of altered morphology. The mutation did not prevent perithecium development and ascosporogenesis. Genetic analyses indicated that a single locus, designated FPH1 (frustrated phialide), was responsible for the mutation. The conidiogenesis mutants were recovered only during certain sexual crosses involving wild-type conidiating parents, and then only in some perithecia, suggesting that mutation of FPH1 might be meiotically induced, perhaps due to mispairing between homologous chromosomes and deletion of the gene from a chromosome. PMID:21148918

Glenn, Anthony E; Richardson, Elizabeth A; Bacon, Charles W

2004-01-01

80

Protective role of Melissa officinalis L. extract on liver of hyperlipidemic rats: A morphological and biochemical study  

Microsoft Academic Search

In this study, the effects of Melissa officinalis L. extract on hyperlipidemic rats were investigated, morphologically and biochemically. The animals were fed a lipogenic diet consisting of 2% cholesterol, 20% sunflower oil and 0.5% cholic acid added to normal chow and were given 3% ethanol for 42 days. The plant extract was given by gavage technique to rats to a

S. Bolkent; R. Yanardag; Omur Karabulut-Bulan; B. Yesilyaprak

2005-01-01

81

Effects of Fixatives and Buffers upon the Morphology of Heart and Skeletal Muscle Mitochondria from Exhausted Rats.  

ERIC Educational Resources Information Center

This study describes the effects of several fixatives and buffers on the morphology of mitochondria from resting and exhausted rats. Rats were run to exhaustion and adjacent portions from the left ventricle or from the soleus were treated with the following fixation procedures: (a) glutaraldehyde buffered with cacodylate, S-collidine, or phosphate…

Gale, James B.

82

Morphological changes of parotid glands following adjuvant arthritis and ibuprofen treatment in rats.  

PubMed

Drug administration and numerous systemic diseases may cause morphological changes of the parotid gland. The aim of this study was to investigate the possible relationship between experimental adjuvant arthritis following ibuprofen treatment and morphological alterations of the parotid glands in rats. Freud's adjuvant was injected intradermally into the plantar surface of the hind paw of the animals to induce experimental arthritis. Ibuprofen was administrated per os (17 mg/kg/day). Both adrenals and parotid glands were isolated and their absolute and relative weights were evaluated. A full histological examination of parotid glands took place. The diameter of the foot as well as the serum levels of rheumatoid factor was measured. In conclusion, both experimental adjuvant arthritis and ibuprofen treatment induce morphological changes of the parotid tissues, which are related to macro- and micro-structure of the gland. PMID:12653236

Mourouzis, C; Saranteas, T; Tsamouris, M; Tesseromatis, C

2003-02-01

83

Streptozotocin-induced diabetes in the rat is associated with changes in vaginal hemodynamics, morphology and biochemical markers  

PubMed Central

Background Diabetes is associated with declining sexual function in women. However, the effects of diabetes on genital tissue structure, innervation and function remains poorly characterized. In control and streptozotocin-treated female rats, we investigated the effects of diabetes on vaginal blood flow, tissue morphology, and expression of arginase I, endothelial nitric oxide synthase (eNOS) and cGMP-dependent protein kinase (PKG), key enzymes that regulate smooth muscle relaxation. We further related these changes with estrogen receptor alpha (ER?) and androgen receptor (AR) expression. Results In addition to significantly elevated blood glucose levels, diabetic rats had decreased mean body weight, lower levels of plasma estradiol, and higher plasma testosterone concentration, compared to age-matched controls. Eight weeks after administration of buffer (control) or 65 mg/kg of streptozotocin (diabetic), the vaginal blood flow response to pelvic nerve stimulation was significantly reduced in diabetic rats. Histological examination of vaginal tissue from diabetic animals showed reduced epithelial thickness and atrophy of the muscularis layer. Diabetic animals also had reduced vaginal levels of eNOS and arginase I, but elevated levels of PKG, as assessed by Western blot analyses. These alterations were accompanied by a reduction in both ER? and AR in nuclear extracts of vaginal tissue from diabetic animals. Conclusion In ovariectomized (estrogen deficient) animals, previous reports from our lab and others have documented changes in blood flow, tissue structure, ER?, arginase I and eNOS that parallel those observed in diabetic rats. We hypothesize that diabetes may lead to multiple disruptions in sex steroid hormone synthesis, metabolism and action. These pathological events may cause dramatic changes in tissue structure and key enzymes that regulate cell growth and smooth muscle contractility, ultimately affecting the genital response during sexual arousal. PMID:16734901

Kim, Noel N; Stankovic, Miljan; Cushman, Tulay T; Goldstein, Irwin; Munarriz, Ricardo; Traish, Abdulmaged M

2006-01-01

84

Adipogenesis of Sprague Dawely rats mesenchymal stem cells: a morphological, immunophenotyping and gene expression follow-up study  

PubMed Central

Mesenchymal stem cells (MSCs) offer significant promise as a multipotent source for cell-based therapies and could form the basis for the differentiation and cultivation of tissue grafts to replace damaged tissue. However, no gene expression follow up analysis has been undertaken to characterize the in vitro adipogenic differentiated MSCs. The main goal of this study was to focus on MSCs and to analyze their differentiation capacity. To achieve this aim, bone marrow MSCs from sprague dawely rats were isolated, expanded in monolayer culture and characterized with respect to their cluster of differentiation (CD) and ability for adipogenic differentiation capacity. The expression of CD44, CD45, CD29, CD34, and CD90 on bone marrow derived MSCs was characterized using flow cytometry. Adipogenesis was determined by staining with oil-red O and reverse transcription polymerase chain reaction assessments of lipoprotein lipase, leptin, adiponectin and adipocyte genes at different time intervals, after 4, 7, 14, and 21 days. Our results revealed that the pattern of CD marker expression was highly positive significant with CD29, CD44, and CD90 when compared with CD34 and CD45. MSCs showed proliferative potential and were capable of adipogenic differentiation characterized by reddish brown-droplets following staining with oil-red O and expression of molecular bands of genes. These results demonstrate, at the morphological, immunophenotyping and gene expression levels, the multipotency of MSCs and thus highlight their potential therapeutic value for cell-based tissue engineering. PMID:24987544

2014-01-01

85

Morphological and receptorial changes in the epididymal adipose tissue of rats subjected to a stressful stimulus.  

PubMed

Obesity is nowadays related to other pathological conditions such as inflammation, insulin resistance, and diabetes, but little is known about the relationship between psychological stress and adipocytes. We decided to study the expression of the translocator protein (TSPO) 18-kDa, peroxisome proliferator-activated receptor-? (PPAR-?), mitochondrial uncoupling protein-1 (UCP-1), and adipocyte morphology in the adipose tissue of rats subjected to stress conditions. In our model of stress, rats fasted for 24 h were placed in a restraint cage and then immersed vertically to the level of the xiphoid process in a water bath at 23 °C for 7 h. After that period, we removed the epididymal adipose tissues for the subsequent analysis. The optical and electron microscopy revealed that adipocytes of control rats formed a continuous epithelial-like cell layer; on the contrary in the adipocytes of stressed rats some cells have merged together and the number of vessels formed seems to increase. Stressed adipocytes presented unilocular cells with numerous mitochondria with a morphology ranging between that of brown adipose tissue (BAT) and white adipose tissue (WAT). Interestingly, when we investigated the subcellular distribution of UCP-1 by immunogold electron microscopy, the adipose tissue of stressed rats was positive for UCP-1. From the immunoblot analysis with anti-PPAR-? antibody, we observed an increased expression of PPAR-? in the adipocytes of stressed group compared with control group (P < 0.05). Stress induced the expression of TSPO 18-kDa receptor (B(max) = 106.45 ± 5.87 fmol/mg proteins), which is undetectable by saturation-binding assay with [(3)H]PK 11195 in the control group. PMID:20948513

Campioli, Enrico; Carnevale, Gianluca; Avallone, Rossella; Guerra, Deanna; Baraldi, Mario

2011-04-01

86

The morphology and classification of ? ganglion cells in the rat retinae: a fractal analysis study.  

PubMed

Rat retinal ganglion cells have been proposed to consist of a varying number of subtypes. Dendritic morphology is an essential aspect of classification and a necessary step toward understanding structure-function relationships of retinal ganglion cells. This study aimed at using a heuristic classification procedure in combination with the box-counting analysis to classify the alpha ganglion cells in the rat retinae based on the dendritic branching pattern and to investigate morphological changes with retinal eccentricity. The cells could be divided into two groups: cells with simple dendritic pattern (box dimension lower than 1.390) and cells with complex dendritic pattern (box dimension higher than 1.390) according to their dendritic branching pattern complexity. Both were further divided into two subtypes due to the stratification within the inner plexiform layer. In the present study we have shown that the alpha rat RCGs can be classified further by their dendritic branching complexity and thus extend those of previous reports that fractal analysis can be successfully used in neuronal classification, particularly that the fractal dimension represents a robust and sensitive tool for the classification of retinal ganglion cells. A hypothesis of possible functional significance of our classification scheme is also discussed. PMID:21839778

Jelinek, Herbert F; Ristanovi?, Dušan; Miloševi?, Nebojša T

2011-09-30

87

Morphology characterization of organic solar cell materials and blends  

NASA Astrophysics Data System (ADS)

The organization of polymers and fullerenes, both in their pure states and mixed together, have a large impact on their macroscopic properties. For mixtures used in organic solar cells, the morphology of the mixture has a very large impact upon the mixture's ability to efficiently convert sunlight into useful electrical energy. Understanding how the morphology can change under certain processing conditions and in turn, affect the characteristics of the solar cell is therefore important to improving the function of organic solar cells. Conventional poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) solar cells have served as a staple system to study organic solar cell function for nearly a decade. Much of the understanding of how to make these "poorly"conductive organic materials efficiently convert sunlight into electricity has come from the study of P3HT:PCBM. It has long been understood that in order for a polymer:fullerene (electron donor and acceptor, respectively) mixture to function well as a solar cell, two major criteria for the morphology must be met; first, the interface between the two materials must be large to efficiently create charges, and secondly, there must be continous pathways through the "pure" materials for charges to be efficiently collected at the electrodes. This makes it advantageous for OPV materials to phase-separate into interconnected domains with very small domain sizes, a structure that P3HT:PCBM seems to naturally self-assemble. Despite P3HT:PCBM's ability to reach an optimal morphology, a complete understanding of exactly how the morphology affects device performance has not been realized. Completely different morphological models can end up predicting the same device performance characteristics. Much of the problem comes from the assumed morphology within a particular model, which can often be incorrect. The problem lies in the fact that obtaining real, accurate morphological information is difficult. An often neglected morphological feature is the existence of a third mixed phase, which is often unaccounted for because much about its composition and location are poorly understood. Obtaining this information and measuring the full morphology of OPV layers would therefore enable further understanding of device function. It is the aim of this thesis to demonstrate a technique which can measure the morphology of OPV layers accurately, accounting for the third phase and its composition. By using a scanning transmission electron microscope (STEM) in conjunction with electron tomography (ET) and an easily resolved fullerene component, the morphology of P3HT:fullerene layers are herein investigated. The combination of materials and techniques are demonstrated to accurately measure the morphology, illustrated by results which corroborate previous studies in the literature. It will be shown that not only can the position of each of the three phases present be measured, but their compositions can also be determined. Through this technique, morphologies formed under different processing conditions are quantitatively compared. The technique reveals differences between conventional processing methods that are not obvious through other measurements. Differences in the materials distribution throughout the thickness of the layer are also demonstrated and shown to give implications toward device function. Additionally, the precise changes in morphology which occur from different processing conditions are determined and shown to have a significant impact upon the properties of an OPV layer as a solar energy harvester. Not only does the morphology of the mixed materials affect the solar cell properties, but the local structure of the component materials themselves can strongly influence the macroscopic properties. By removing the fullerene component and forming pure domains of P3HT, the effects of internal structure on the properties of P3HT and how the structure is formed is also herein investigated. Through these techniques, the morphology and structure of diffe

Roehling, John Daniel

88

Effects of Prenatal Testosterone on Sexual Behavior, Reproductive Morphology and LH Secretion in the Female Rat  

Microsoft Academic Search

Sexual differentiation of many brain structures and functions is dependent on levels of testosterone (T) or its metabolites during certain 'sensitive' developmental periods. If T is present during these perinatal periods, masculinization and defeminization of sexual behavior occur; also, reproductive physiology, and central nervous system morphology and function are altered. The purpose of the present study was to characterize the

Reuben W. Rhees; Blair A. Kirk; Sandra Sephton; Edwin D. Lephart

1997-01-01

89

Characterization of Colony Morphology Variants Isolated from Pseudomonas aeruginosa Biofilms  

PubMed Central

In this study, we report the isolation of small, rough, strongly cohesive colony morphology variants from aging Pseudomonas aeruginosa PAO1 biofilms. Similar to many of the P. aeruginosa colony morphology variants previously described in the literature, these variants autoaggregate in liquid culture and hyperadhere to solid surfaces. They also exhibit increased hydrophobicity and reduced motility compared to the wild-type parent strain. Despite the similarities in appearance of our colony morphology variant isolates on solid medium, the isolates showed a range of responses in various phenotypic assays. These variants form biofilms with significant three-dimensional structure and more biomass than the wild-type parent. To further explore the nature of the variants, their transcriptional profiles were evaluated. The variants generally showed increased expression of the psl and pel loci, which have been previously implicated in the adherence of P. aeruginosa to solid surfaces. When a mutation in the psl locus was introduced into a colony morphology variant, the colony morphology was only partially affected, but hyperadherence and autoaggregation were lost. Finally, similar colony morphology variants were found in isolates from cystic fibrosis patients. These variants displayed many of the same characteristics as the laboratory variants, suggesting a link between laboratory and cystic fibrosis biofilms. PMID:16085879

Kirisits, Mary Jo; Prost, Lynne; Starkey, Melissa; Parsek, Matthew R.

2005-01-01

90

Morphological changes in cultures of hippocampus following prenatal irradiation in the rat  

SciTech Connect

The effect of prenatal irradiation was studied in organotypic cultures of hippocampus, prepared from newborn rats that had been exposed to whole-body irradiation of 1 Gy from a {sup 60}Co-source at day 13 of pregnancy. Light and electron microscopic observations showed remarkable damage to neuronal mitochondria accompanied by extensive swelling, vacuolation of the Golgi complex, and formation of multilamellar bodies and vesicles of the lysosomal type. In contrast to neuronal alterations, no delay in synaptogenesis or onset of myelination was observed based upon the absence of significant morphological changes in synapses and myelin sheaths. Using this tissue culture model it could be confirmed that prenatal exposure to irradiation, even at low doses, induces specific morphological changes in the brain.

Hamdorf, G.; Shahar, A.; Cervos-Navarro, J.; Scheffler, A.; Sparenberg, A.; Skoberla, A. (Free Univ. of Berlin (Germany, F.R.))

1990-07-01

91

Loading effects on rat craniomandibular morphology: a system for gravity studies  

NASA Astrophysics Data System (ADS)

Gravity effects on muscle and bone are a major impediment to long-term space travel. We introduce a model for studying these effects, the craniomandibular system. Some advantages of this system include: (1) craniomandibular morphology is determined by epigenetic factors including gravity, (2) relatively light forces can significantly alter its morphology, and (3) soft diet and tooth loss produce effects that are similar to those produced in lower limbs by weightlessness. In the study, implants made either of gold (experimental group) or lightweight acrylic (controls) were attached to adult rats' mandibles. After 13 weeks, the animals' skulls and mandibles were dissected. Pair-wise comparisons indicated that the experimental animals showed significantly shortened and narrowed cranial bases, and significant changes in the posterior zygomatic arch region. These results indicate that simulated macrogravity influences bone remodeling in the adult craniomandibular system.

Singh, Ranbir; Carvalho, Thais; Gerstner, Geoffrey E.

2005-02-01

92

Morphological, Pathogenic, and Molecular Characterization of Alternaria Isolates Associated with Alternaria Late Blight of Pistachio  

Microsoft Academic Search

ABSTRACT Pryor, B. M., and Michailides, T. J. 2002. Morphological, pathogenic, and molecular characterization of ,Alternaria isolates associated with Alternaria late blight of pistachio. Phytopathology 92:406-416. Alternaria isolates ,were ,obtained from ,various pistachio tissues

Barry M. Pryor; Themis J. Michailides

2002-01-01

93

Morphological Control and Characterization of Monodispersed Ceria Particles  

SciTech Connect

The morphological control of cerium oxide particles was carried out by a homogeneous precipitation followed by calcination in air at 400 deg. C. The effects of pre-aging temperature, aging time and precipitation reagents on the morphologies of final products were investigated. When urea was used as a precipitation reagent, monodispersed spherical and flake-like cerium carbonate hydroxide precursor was precipitated in the solution at 90 deg. C for 2 h after pre-aging at 25 deg. C - 50 deg. C for 24-72 h. On the other hand, monodispersed nanosize rod-like cerium hydroxide particles were obtained using triethanolamine as precipitation reagent. Ceria particles with the same morphologies and slightly smaller particle size than those of as-prepared cerium precursor could be obtained after calcination in air at 400 deg. C. Physical-chemical characteristics of the monodispersed cerium oxide particles were evaluated.

Minamidate, Y.; Yin, S.; Devaraju, M. K.; Sato, T. [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai (Japan)

2010-11-24

94

Electrophysiological and morphological properties of interneurones in the rat dorsal lateral geniculate nucleus in vitro.  

PubMed Central

1. Intracellular recordings were made from putative interneurones (n = 24) and thalamocortical (TC) projection neurones (n = 45) in slice preparations of the rat dorsal lateral geniculate nucleus (dLGN) in order to compare the electrophysiological properties of these neuronal types. 2. Intracellular injection of biocytin to electrophysiologically identified neurones (n = 34) revealed the morphology of putative interneurones (n = 4) to be similar to class B and that of TC neurones (n = 30) to be similar to class A Golgi-impregnated neurones. 3. Interneurones had resting membrane potentials (-52 mV) relatively positive to those of TC neurones (-63 mV), shorter time constants (36.8 and 58.2 ms, respectively), but similar steady-state input resistances (164 and 180 M omega, respectively). Steady-state voltage-current relationships were nearly linear in interneurones, but highly non-linear in TC neurones. 4. The structure of action potential firing evoked at the break of hyperpolarizing voltage transients was dependent upon neuronal type. Interneurones fired a single action potential or a burst of action potentials with a maximum frequency of < 130 Hz, whilst TC neurones fired a high frequency burst with a minimum frequency of > 250 Hz. In addition, well-defined burst firing of action potentials in response to depolarizing voltage excursions, from membrane potentials negative to -65 mV, could be evoked in TC neurones, but not in interneurones. 5. The directly evoked action potentials of interneurones were characterized by an initial slow pre-potential preceding the fast upstroke of the action potential. The amplitude and width of interneurones' action potentials were smaller than those of TC neurones and the amplitude and duration of the single action potential after-hyperpolarization were greater in interneurones. Both interneurones and TC neurones fired action potentials repetitively in response to suprathreshold voltage excursions, with interneurones demonstrating a greater degree of spike-frequency adaptation. Following a train of action potentials, interneurones and TC neurones generated a slow after-hyperpolarizing potential: in interneurones but not TC neurones this potential was followed by a slow depolarizing potential. 6. An intrinsic, subthreshold membrane potential oscillatory activity with a mean frequency of approximately 8 Hz was observed in interneurones. 7. Electrical stimulation of the optic tract evoked in interneurones apparently pure EPSPs, pure IPSPs or a mixture of EPSPs and IPSPs. EPSPs were found to be biphasic and mediated by the activation of non-N-methyl-D-aspartate (NMDA) and NMDA excitatory amino acid receptors. IPSPs and the response to the iontophoretic application of GABA were found to reverse between -65 and -70 mV. The application of GABAB receptor agonists failed to affect the membrane properties of six of seven interneurones tested. In addition spontaneous EPSPs and IPSPs were recorded in interneurones. 8. These results demonstrate that the electrophysiological properties of putative interneurones are distinct from those of TC neurones of the rat dLGN. The implications of these findings for the control of visual responsiveness of TC neurones are discussed. PMID:8745283

Williams, S R; Turner, J P; Anderson, C M; Crunelli, V

1996-01-01

95

Morphological changes of gonadotropin-releasing hormone neurons in the rat preoptic area across puberty  

PubMed Central

Gonadotropin-releasing hormone (GnRH) neurons in the preoptic area may undergo morphological changes during the pubertal period when their activities are upregulated. To clarify the regulatory mechanism of puberty onset, this study aimed to investigate the morphological changes of GnRH neurons in the preoptic area of GnRH-enhanced green fluorescent protein transgenic rats. Under confocal laser microscopy, pubertal GnRH neurons exhibited an inverted Y distribution pattern. Prepubertal GnRH neurons were generally unipolar and bipolar, and were distinguished as smooth type cells with few small processes or irregular type cells with many spine-like processes in the proximal dendrites. The number of GnRH neurons in the preoptic area and spine-like processes were increased during the course of reproductive maturation. There was no significant difference between male and female rats. Immunofluorescence staining revealed synaptophysin punctae close to the distal end of GnRH neurons, indicating that some presynaptic terminals may form a synaptic linkage with these neurons. PMID:25221583

Xue, Haogang; Gai, Xiaodong; Sun, Weiqi; Li, Chun; Liu, Quan

2014-01-01

96

Sertoli cell morphological alterations in albino rats treated with etoposide during prepubertal phase.  

PubMed

Sertoli cells are very important to spermatogenesis homeostasis because they control germ cell proliferation, differentiation, and death. Damages to Sertoli cells cause germ cell death and affect fertility. Etoposide is a potent chemotherapeutic drug largely used against a variety of cancers. However, this drug also kills normal cells, especially those undergoing rapid proliferation. In the testis, etoposide acts predominantly on intermediate and type B spermatogonia. Etoposide was shown to permanently alter Sertoli cell function when administered to prepubertal rats. Based on this, we decided to investigate whether etoposide can affect Sertoli cell morphology. For this, 25-day-old rats were treated with etoposide during 8 consecutive days and killed at 32, 45, 64, 127, and 180 days old. Testes were fixed in Bouin's liquid or in a mixture of 2.5% glutaraldehyde and 2% formaldehyde for analysis under light and electron microscopes, respectively. Sertoli cells showed morphological alterations such as the presence of chromatin clumps close to the nuclear membrane, nucleus displacement, and cytoplasmic vacuolization. Some Sertoli cells also showed nuclear and cytoplasmic degenerative characteristics, suggesting that etoposide causes severe damages to Sertoli cell. PMID:18482470

Stumpp, Taiza; Freymuller, Edna; Miraglia, Sandra M

2008-06-01

97

The morphological and neurochemical effects of diffuse brain injury on rat central noradrenergic system.  

PubMed

The central noradrenergic system is widely distributed throughout the brain and is closely related to spontaneous motility and level of consciousness. The study presented here evaluated the morphological as well as neurochemical effects of diffuse brain injury on the central noradrenergic system in rat. Adult male Sprague-Dawley rats were subjected to impact-acceleration brain injury produced with a weight-drop device. Morphological changes in locus coeruleus (LC) neurons were examined by using immunohistochemistry for dopamine-beta-hydroxylase, and norepinephrine (NE) turnover in the cerebral cortex was measured by high performance liquid chromatography with electrochemical detection. The size of LC neurons increased by 11% 24 h after injury but had decreased by 27% seven days after injury. Axons of noradrenergic neurons were swollen 24 h and 48 h after injury but the swelling had dwindled in seven days. NE turnover was significantly reduced seven days after injury and remained at a low level until eight weeks after injury. These results suggest that focal impairment of axonal transport due to diffuse brain injury causes cellular changes in LC and that the neurochemical effect of injury on the central noradrenargic system lasts over an extended period of time. Chronic suppression of NE turnover may explain the sustained behavioral and psychological abnormalities observed in a clinical situation. PMID:12564124

Fujinaka, Toshiyuki; Kohmura, Eiji; Yuguchi, Takamichi; Yoshimine, Toshiki

2003-01-01

98

In vitro characterization of rat thymic macrophages.  

PubMed Central

Thymic macrophages have been isolated from Wistar rats and maintained in long-term culture. Day 1-isolated thymic macrophages expressed MHC class I and II antigens, Thy-1, CR3, CD4, ED1, ED2, as well as acid phosphatase and non-specific esterase activities. Whereas cultured macrophages were positive for the activation antigen recognized by the mAb OX48, which was not expressed after isolation, MHC class II and Thy-1 expression were down-regulated during the culture, but could be induced with human rIL-2 or with Con A-SCM, which are also inducers of IL-2R, a cell-surface marker not expressed on Day 1 or on cultured macrophages. PMID:1675199

Navarro, R; Ardavin, C; Fontecha, A M; Alvarez, A; Zapata, A

1991-01-01

99

Molecular and morphological characterization of Eimeria in game birds.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Coccidiosis is generally known as a disease of economic importance in chickens. However, Eimeria species also negatively impacts the game bird industry. Here we present data generated from litter samples collected from two farms experiencing coccidiosis in chukars and pheasants. From morphological...

100

Morphological Characterization of Symmetric Diblock Copolymers Via Novel Combinatorial Methods  

NSDL National Science Digital Library

We have developed a technique to create polymer thin films with a controlled, continuous gradient in film thickness. As a demonstration of the utility of this technique, we have revisited the well-studied phenomena of the morphology of symmetric diblock copolymer thin films.

Smith, Archie

2000-01-01

101

Melatonin protects against clomiphene citrate-induced generation of hydrogen peroxide and morphological apoptotic changes in rat eggs  

Microsoft Academic Search

The present study was aimed to determine whether clomiphene citrate-induces generation of hydrogen peroxide in ovary, if so, whether melatonin could scavenge hydrogen peroxide and protect against clomiphene citrate-induced morphological apoptotic changes in rat eggs. For this purpose, forty five sexually immature female rats were given single intramuscular injection of 10IU pregnant mare's serum gonadotropin for 48h followed by single

Anima Tripathi; Karuppanan V. PremKumar; Ashutosh N. Pandey; Sabana Khatun; Surabhi Kirti Mishra; Tulsidas G. Shrivastav; Shail K. Chaube

2011-01-01

102

Morphological Analysis of the Enamel Organ in Rats Treated with Fluoxetine  

PubMed Central

PURPOSE: Previous studies have evaluated the presence of serotonin in the dental epithelia and mesenchyme during odontogenesis, suggesting its participation in tooth development. MATERIALS AND METHODS: Here, we used fluoxetine, a selective serotonin re-uptake inhibitor, at a dose of 10 mg/kg, administered for 20 days during pregnancy in 12 Wistar rats to examine the influence of this drug on the development of the enamel organ of the upper first molars of rat fetuses at 17 days of intra-uterine life (i.u.l.), and at one, five and ten days postpartum. The pregnant rats were anesthetized with xylazine at 10 mg/kg and ketamine at 25 mg/kg. The fetuses were removed and beheaded; their jaws were removed, and the upper jaws were exposed. The tissues were fixed in Bouin’s fixative, decalcified in 5% nitric acid for 4 – 12 h, conventionally processed for microscopy, and embedded in paraffin. Serial sections of approximately 5 ?m were obtained and stained with hematoxylin and eosin, as well as periodic acid-Schiff. RESULTS AND CONCLUSION: Morphological analysis showed no structural changes in the experimental group compared to the controls, suggesting that, at the dose used, fluoxetine does not interfere with serotonin-mediated development of the enamel organ or the process of amelogenesis. PMID:20126347

Silva, Igor Henrique Morais; Leăo, Jair Carneiro; Evęncio, Liriane Baratella; Porter, Stephen Ross; de Castro, Raul Manhăes

2010-01-01

103

Ultra-structural morphological abnormalities of the urinary bladder in streptozotocin-induced diabetic female rats.  

PubMed

The objective of this study was to evaluate the ultra-structural changes in the urinary bladder of diabetic rats in relation to disease duration since the morphological bases of diabetes-induced bladder dysfunction are poorly understood. Urinary bladders were examined chronologically by electron microscopy in a female Wistar-rat model of streptozotocin-induced diabetes mellitus and compared to control samples. Numerous dark mitochondria with swollen cristae and electron lucent, large, calcified and degenerated mitochondria were observed first in the urothelium. Intraepithelial capillaries surrounded by thick collagen were also present. Gap junctions between myocytes were interrupted or extensively widened with reduced mitochondria and caveolae. Collagen accumulation, degenerated nerve fibres and myelin bodies were seen between myocytes with increased collagen content and frequent mast cells, phagocytes and lymphocyte aggregates in the stroma. All ultra-structural lesions became augmented with longer duration of diabetes. Diabetes induces time-dependent pathologic changes in the urinary bladder of rats that might account for bladder dysfunction. PMID:16021327

Rizk, Diaa E E; Padmanabhan, Rengasamy K; Tariq, Saeed; Shafiullah, Mohamed; Ahmed, Ijaz

2006-02-01

104

Interaction between rat peritoneal macrophages and sialidase-treated erythrocytes: biochemical and morphological studies.  

PubMed

Rat peritoneal macrophages bind and phagocytose homologous, sialidase-treated erythrocytes at a rate depending on the number of red cells and the amount of sialic acids released. Vibrio cholerae sialidase only partially (75%) removes the sialic acid residues from rat erythrocytes, whereas with Arthrobacter ureafaciens sialidase complete desialylation is possible. Analysis of the sialic acids by capillary gas-liquid chromatography combined with mass spectrometry (GLC-MS) revealed the occurrence of N-acetylneuraminic acid (Neu5Ac), N-acetyl-9-O-acetylneuraminic acid (Neu5,9Ac2), N-acetyl-7,9-di-O-acetylneuraminic acid (Neu5,7,9Ac3), N-acetyl-9-O-lactylneuraminic acid (Neu5Ac9Lt) and N-glycolyneuraminic acid (Neu5Gc). Native rat serum enhances binding and phagocytosis, as has been observed by radioactive measurements and studies in a micro-scale by light and electron microscopy. The morphological experiments showed that maximum binding of sialidase-treated erythrocytes to macrophages occurs after 15-30 min, while for maximum phagocytosis at least 60 min are necessary. Striking alterations of the shape of erythrocytes during their interaction with macrophages were observed. PMID:6487288

Schauer, R; Schröder, C; Müller, E; von Gaudecker, B

1984-01-01

105

Pigment epithelium-derived factor protects the morphological structure of retinal Müller cells in diabetic rats  

PubMed Central

AIM To investigate if pigment epithelium-derived factor (PEDF) has any protective effect on the retinal Müller cells of Sprague-Dawley rats suffering from diabetes mellitus. METHODS Sixty Sprague-Dawley rats were randomly divided into a negative control group, a group receiving 0.1 µg/µL PEDF, another group receiving 0.2 µg/µL PEDF, and a group receiving balanced salt solution (BSS). Rats in both the PEDF and BSS groups were treated intravitreally based on previously established diabetic models. After 4wk of treatment, morphological alterations of Müller cells and protein expression of glutamine synthase (GS) and glial fibrillary acidic protein (GFAP) were analyzed. RESULTS PEDF at either 0.1 µg/µL or 0.2 µg/µL significantly improved the structures of both nuclei and organelles of Müller cells compared to the BSS-treated group. Expression of GS was significantly higher in the 0.2 µg/µL PEDF group than that in the BSS group (P=0.012), but expression of GFAP was significantly lower in the 0.2 µg/µL PEDF group than that in the BSS group (P=0.000); however, there were no significant differences in expression of these proteins between the 0.1 µg/µL PEDF group and the BSS group (P=0.608, P=0.152). CONCLUSION PEDF protects the morphological ultrastructure of Müller cells, improves the expression of glutamate synthase and prevents cell gliosis.

Zhang, Xiao-Hui; Feng, Zhao-Hui; Zhang, Yi

2014-01-01

106

Sucralose sweetener in vivo effects on blood constituents radiolabeling, red blood cell morphology and radiopharmaceutical biodistribution in rats  

Microsoft Academic Search

Effects of sucralose sweetener on blood constituents labelled with technetium-99m (99mTc) on red blood cell (RBC) morphology, sodium pertechnetate (Na99mTcO4) and diethylenetriaminepentaacetic acid labeled with 99mTc (99mTc-DTPA) biodistribution in rats were evaluated. Radiolabeling on blood constituents from Wistar rats was undertaken for determining the activity percentage (%ATI) on blood constituents. RBC morphology was also evaluated. Na99mTcO4 and 99mTc-DTPA biodistribution was

G. S. Rocha; M. O. Pereira; M. O. Benarroz; J. N. G. Frydman; V. C. Rocha; M. J. Pereira; A. S. Fonseca; A. C. Medeiros; M. Bernardo-Filho

2011-01-01

107

Dendritic morphology of neurons in prefrontal cortex and ventral hippocampus of rats with neonatal amygdala lesion.  

PubMed

Neonatal basolateral amygdala (nBLA) lesions in rats have been widely used as a neurodevelopmental model that mimics schizophrenia-like behaviors. Recently, we reported that nBLA lesions result in significant decreases in the dendritic spine number of layer 3 prefrontal cortex (PFC) pyramidal cells and medium spiny neurons of the nucleus accumbens (NAcc), which all changes after puberty. At present, we aimed to evaluate the effect of this lesion in pyramidal neurons of CA1 of the ventral hippocampus (VH) and layer 5 of the PFC. In order to assess the effects of nBLA lesions on the dendritic morphology of the PFC and VH neurons, we carried out nBLA lesions in rats on postnatal day (PD) 7, and then we studied the dendritic morphology of these two limbic subregions at prepubertal (PD35) and postpubertal (PD60) ages. Dendritic characteristics were measured by Golgi-Cox procedure followed by Sholl analysis. We also evaluated the effects of nBLA lesions on the prepulse inhibition (PPI) and acoustic startle responses. The nBLA lesion induced a significant increase in dendritic length of layer 5 pyramidal neurons of the PFC at both ages, with a decrease in the dendritic spines density after puberty. The spine density of CA1 VH pyramidal neurons showed significant decreases at both ages. PPI was decreased in adulthood in the animals with an nBLA lesion. These results show that an nBLA lesion alters the dendritic morphology at the level of the PFC and VH in distinct ways before puberty, suggesting a disconnection between these limbic structures at an early age, and increasing our understanding of the implications of the VH in early amygdala dysfunction in schizophrenia. PMID:22170567

Vázquez-Roque, Rubén Antonio; Solis, Oscar; Camacho-Abrego, Israel; Rodríguez-Moreno, Antonio; Cruz, Fidel De La; Zamudio, Sergio; Flores, Gonzalo

2012-05-01

108

Stasis and convergence characterize morphological evolution in eupolypod II ferns  

PubMed Central

Background and Aims Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional ‘athyrioid’ ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Methods Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. Key Results The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species. Conclusions The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae – a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation. PMID:24197753

Sundue, Michael A.; Rothfels, Carl J.

2014-01-01

109

Synthesis and characterization of different morphological SnS nanomaterials  

NASA Astrophysics Data System (ADS)

SnS in three nano forms possessing different morphologies such as particles, whiskers and ribbons were synthesised by chemical route. The morphology variation was brought about in the chemical route synthesis by varying a synthesis parameter such as temperature and influencing the synthesis by use of surfactant. The elemental composition determination by energy dispersive analysis of x-rays (EDAX) showed that all three synthesized SnS nanomaterials were tin deficient. The x-ray diffraction (XRD) study of the three SnS nanomaterials showed that all of them possess orthorhombic structure. The Raman spectra of the three SnS nanomaterials showed that all three samples possess three common distinguishable peaks. In them two peaks lying at 98 ± 1 cm?1 and 224 ± 4 cm?1 are the characteristic Ag mode of SnS. The third peak lying at 302 ± 1 cm?1 is associated with secondary Sn2S3 phase. The transmission electron microscopy (TEM) confirmed the respective morphologies. The optical analysis showed that they possess direct as well as indirect optical bandgap. The electrical transport properties study on the pellets prepared from the different nanomaterials of SnS showed them to be semiconducting and p-type in nature. The current–voltage (I–V) plots of the silver (Ag)/SnS nanomaterials pellets for dark and incandescent illumination showed that all configurations showed good ohmic behaviour except Ag/SnS nanoribbons pellet configuration under illumination. All the obtained results are discussed in detail.

Chaki, Sunil H.; Chaudhary, Mahesh D.; Deshpande, M. P.

2014-12-01

110

Characterization of DNA methylation in the rat.  

PubMed

In the rat, differentiation and cell proliferation both affect DNA methylation. We studied 5-methylcytosine at the inner cytosine of the sequence C-C-G-G, a common methylation site, using endonuclease MspI (which cleaves C-C-G-G- and C-mC-G-G), and its isoschizomer HpaII (which cleaves only C-C-G-G). DNA from all tissues and cell lines studied was methylated at C-C-G-G, at levels ranging from 45 to 80%, but the methylation sites were not distributed uniformly. Our analysis suggests a model in which cells contain variable amounts of three DNA methylation states, averaging 30-40, 70-80 and 95-100% methylation, respectively. One biological parameter that alters methylation is the proliferative state of the cell. We observed that NRK, a non-transformed cell line, increased its DNA methylation from 45 to 67% when monolayer cultures became confluent and non-dividing. We also observed that a class of repetitive DNA was completely methylated in DNA from all sources except a transformed cell line. PMID:6297564

Kunnath, L; Locker, J

1982-12-31

111

Determination and Characterization of a Cannabinoid Receptor in Rat Brain  

Microsoft Academic Search

SUMMARY The determination and characterization of a cannabinoid receptor from brain are reported. A biologically active bicyclic cannabinoid analgetic CP-55,940 was tntium-Iabeled to high specific activity. Conditions for binding to rat brain P2 membranes and synapto- somes were established. The pH optimum was between 7 and 8, and specific binding could be eliminated by heating the mem- branes to 60#{176}.

WILLIAM A. DEVANE; FRANCIS A. DYSARZ; M. ROSS JOHNSON III; LAWRENCE S. MELVIN; ALLYN C. HOWLETT

112

Molecular cloning and characterization of the rat NMDA receptor  

Microsoft Academic Search

A complementary DNA encoding the rat NMDA receptor has been cloned and characterized. The single protein encoded by the cDNA forms a receptor-channel complex that has electrophysiological and pharmacological properties characteristic of the NMDA receptor. This protein has a significant sequence similarity to the AMPA\\/kainate receptors and contains four putative transmembrane segments following a large extracellular domain. The NMDA receptor

Koki Moriyoshi; Masayuki Masu; Takahiro Ishii; Ryuichi Shigemoto; Noboru Mizuno; Shigetada Nakanishi

1991-01-01

113

Glomerular dynamics and morphologic changes in the generalized Shwartzman reaction in postpartum rats.  

PubMed Central

The roles of glomerular functional and morphologic changes were examined in the acute renal failure associated with generalized Shwartzman reaction in postpartum Munich Wistar rats. The susceptibility of postpartum rats to acute deterioration in renal function after a 2-h endotoxin infusion was found to be greater than in virgin litter mates: glomerular filtration rate fell by 93% in the former vs. 24% in the latter group (P less than 0.001). In postpartum rats there were marked changes in platelet count and fibrinogen level (P less than 0.025) compatible with consumption coagulopathy. Renal blood flow and glomerular filtration rate fell from 5.5 +/- 0.9 and 0.74 +/- 0.12 to 2.0 +/- 0.7 and 0.12 +/- 0.01 ml/min, respectively (both P less than 0.001). Blood pressure did not change. Results of glomerular dynamics studies showed decreases in single nephron filtration rate from 28 +/- 7 to 6 +/- 4 nl/min and in glomerular plasma flow rate from 77 +/- 26 to 23 +/- 12 nl/min (both P less than 0.001). Afferent net ultrafiltration pressure fell from 20 +/- 3 to 5 +/- 4 mm Hg due to a fall in glomerular capillary hydraulic pressure from 47 +/- 1 to 29 +/- 5 mm Hg (P less than 0.001). There were four- and twofold increases in afferent and efferent arteriolar resistances, respectively. Less than 20% of glomeruli had evidence of fibrin deposition after 2 h of endotoxin infusion, a time when glomerular filtration rate was reduced by greater than 90%. [1-Sar, 5-Ile, 8-Gly] angiotensin II infusion before endotoxin significantly protected glomerular filtration rate, 62 vs. 7% of control in rats with no preinfusion (P less than 0.01) despite consumption coagulopathy and glomerular fibrin deposition similar to rats without pretreatment. These data suggest that the early deterioration in renal function in the generalized Shwartzman reaction in the postpartum rat is due to major changes in glomerular dynamics induced by neurohumoral agents and that glomerular fibrin deposition plays a lesser pathogenetic role at this time in this disorder. The study does not address the pathogenesis of renal failure in pregnancy nor peripartum renal failure in another species. Images PMID:7014634

Conger, J D; Falk, S A; Guggenheim, S J

1981-01-01

114

Insights into Embryo Defenses of the Invasive Apple Snail Pomacea canaliculata: Egg Mass Ingestion Affects Rat Intestine Morphology and Growth  

PubMed Central

Background The spread of the invasive snail Pomacea canaliculata is expanding the rat lungworm disease beyond its native range. Their toxic eggs have virtually no predators and unusual defenses including a neurotoxic lectin and a proteinase inhibitor, presumably advertised by a warning coloration. We explored the effect of egg perivitellin fluid (PVF) ingestion on the rat small intestine morphology and physiology. Methodology/Principal Findings Through a combination of biochemical, histochemical, histopathological, scanning electron microscopy, cell culture and feeding experiments, we analyzed intestinal morphology, growth rate, hemaglutinating activity, cytotoxicity and cell proliferation after oral administration of PVF to rats. PVF adversely affects small intestine metabolism and morphology and consequently the standard growth rate, presumably by lectin-like proteins, as suggested by PVF hemaglutinating activity and its cytotoxic effect on Caco-2 cell culture. Short-term effects of ingested PVF were studied in growing rats. PVF-supplemented diet induced the appearance of shorter and wider villi as well as fused villi. This was associated with changes in glycoconjugate expression, increased cell proliferation at crypt base, and hypertrophic mucosal growth. This resulted in a decreased absorptive surface after 3 days of treatment and a diminished rat growth rate that reverted to normal after the fourth day of treatment. Longer exposure to PVF induced a time-dependent lengthening of the small intestine while switching to a control diet restored intestine length and morphology after 4 days. Conclusions/Significance Ingestion of PVF rapidly limits the ability of potential predators to absorb nutrients by inducing large, reversible changes in intestinal morphology and growth rate. The occurrence of toxins that affect intestinal morphology and absorption is a strategy against predation not recognized among animals before. Remarkably, this defense is rather similar to the toxic effect of plant antipredator strategies. This defense mechanism may explain the near absence of predators of apple snail eggs. PMID:24945629

Gimeno, Eduardo J.; Heras, Horacio

2014-01-01

115

Morphological and molecular characterization of healthy human ascending aorta.  

PubMed

Knowledge of the characteristics of the normal human aorta has been constrained by lack of data on fresh aortic tissue, especially from healthy individuals. In this study, the gene expression and morphological characteristics of the thoracic ascending aorta (AA) of healthy organ donors have been evaluated, with the aim of providing reference data for the analysis of pathological AAs. We analysed by RT-PCR the differential expression of mRNAs coding for myocardin, smoothelin, alpha-smooth muscle actin (alpha-SMA) and the ED-A isoform of fibronectin (ED-A FN) in AA specimens from donors, integrating the results with immunohistochemical analysis of the same targets. Morphological and morphometric characteristics of the AAs were also evaluated. In order to account for possible regional variations in wall structure, the convexity of the aortic profile was compared to the concavity. No differences in gene expression occurred for any of the target genes between the concavity and the convexity of AAs. Immunohistochemistry revealed a different distribution of total FN and of its ED-A isoform in the media and in the intima. Smoothelin is expressed by the majority of cells in the media, with some positive cells also in the intima. Alpha-SMA is expressed in all the tunicae. Immunohistochemistry also revealed in the convexity of 50% of AAs the presence of discrete areas in the subadventital media with altered structure and cell morphology and with altered gene expression, resulting positive for ED-A FN and alpha-SMA, but not for smoothelin, indicating the occurrence of early lesions also in macroscopically healthy AAs. PMID:22127602

Forte, A; Della Corte, A; Grossi, M; Finicelli, M; Bancone, C; Provenzano, R; Pepino, P; Nappi, G A; De Feo, M; Galderisi, U; Cotrufo, M; Cipollaro, M

2012-01-01

116

Intrauterine Exposure to a Maternal Low Protein Diet Reduces Adult Bone Mass and Alters Growth Plate Morphology in Rats  

Microsoft Academic Search

Epidemiological studies suggest that poor growth during fetal life and infancy is associated with decreased bone mass in adulthood. However, theses observations have not, to date, been corroborated in animal models. To address this issue we evaluated the influence of maternal protein restriction on bone mass and growth plate morphology among the adult offspring, using a rat model. Maternal protein

G. Mehta; H. I. Roach; S. Langley-Evans; P. Taylor; I. Reading; R. O. C. Oreffo; A. Aihie-Sayer; N. M. P. Clarke; C. Cooper

2002-01-01

117

The morphology, deformability and microvascular arrest of rat fibrosarcoma and adenocarcinoma cells.  

PubMed

The deformation and flow properties of tumour cells may play a role in their arrest in the microvasculature of different organs. In the present investigation the morphology, deformability and microvascular arrest in the liver of rat fibrosarcoma cells (FSCs) and adenocarcinoma cells (ACCs) were compared using electron microscopy, deformability measurements in narrow glass pipettes and isotope-labelling techniques. The ACCs had a larger mean diameter (13.9 microns) than the FSCs (10.9 microns) and showed a slower rate of deformation into 6.5 microns glass pipettes. A significantly larger percentage of ACCSs (52.4%) than of FSCs (19.9%) remained in the livers 5 min after intraportal injection. The results indicate that for the particular tumour cells studied here, there exists a relationship between cell deformability and the tendency for microvascular trapping in the liver, i.e. less deformable cells have a greater tendency for retention in the liver. PMID:1890138

Nannmark, U; Bagge, U; Johansson, B R; Skolnik, G

1991-01-01

118

Morphological changes of rats muscles at various postmortem intervals by scanning electron microscopy.  

PubMed

The aim of this study was to observe the morphological changes of muscle in the process of rigor mortis. The quadriceps of 40 rats at various postmortem intervals were observed under the scanning electron microscope (SEM) and the light microscope by phosphotungstic acid-haematoxylin (PTAH) stain. The results showed that the striations of muscle were blurred within 4 h, but they became apparent from 6 h to 24 h after death. The authors suggest that this phenomenon be associated with the increased resistance of muscle against the postmortal changes. The observations by scanning electron microscopy and light microscopy have revealed that the muscles do contract in the process of rigor mortis because the distance between two Z lines shortens and the 1 band narrows, compared with those in anaesthetised animals. The basic biochemical process for the formation of rigor mortis is the same as that of muscle contraction except that the former happens postmortem and the latter antemortem. PMID:12894904

Zhigang, L; Xufu, Y; Fei, X; Xuemei, P

1999-12-01

119

Characterization of initiated cells in N-methylnitrosourea-induced carcinogenesis of the CNS in the adult rat.  

PubMed Central

Glial tumors may originate from the malignant transformation of multipotent glial progenitor cells, but tools to study malignant transformation leading to gliomas are limited by the lack of biological systems that represent early stages of this disease in adult animals. In order to characterize the initiated cells that give rise to gliomas, we have employed the N-methylnitrosourea (MNU) model for induction of brain tumors in adult rats (Rushing et al., 1998). Specifically, we have isolated and cultured transformed (premalignant) cells from normal-appearing brains of rats exposed to MNU for 10 weeks and from histologically abnormal brains of rats exposed to MNU for 15 weeks. We compared them with cells cultured from control animals under identical conditions. Cultured cells were classified according to their morphology, immunophenotype, karyotype, proliferation capacity, and tumorigenicity in athymic mice. Cultures from untreated normal rat brains grew as monolayers and had normal karyotypes (42 X,Y), epithelioid morphology, and slow proliferative capacity (doubling time > 120 h). In contrast, cultured cells from brains of MNU-exposed animals had karyotypes that ranged from normal to highly aneuploid. Aneuploid lines grew rapidly in multilayers (doubling time < 24 h), had differentiated astrocytic or oligodendroglial morphology and immunohistochemical staining profile, and yielded tumors in athymic mice. Initiated cells with minor chromosomal aberrations assumed mixed bipolar or tripolar morphologies in high density cultures, proliferated rapidly, but showed contact inhibition and failed to induce tumors when injected s.c. in athymic mice. In general, lines showing no evidence of chromosomal aberrations had the most epithelioid morphology, proliferated slowly (doubling time > 72 h), and retained strict contact growth inhibition. The presumed undifferentiated glial progenitor cells in culture from either control or MNU-treated rats variably expressed markers such as vimentin, nestin, and NG2 proteoglycan, and they weakly expressed the mature astrocytic or oligodendroglial markers glial fibrillary acidic protein or galactocerbroside, respectively. These cultures differentiated to bipolar-tripolar morphology with concomitant maturation to a GFAP+ or GalC+ phenotype upon exposure to secondary messengers such as dibutyryl-cyclic-AMP and/or growth factors such as basic fibrillary growth factor. Continuous stimulation with these messengers resulted in terminal differentiation and consequent death upon withdrawal of the stimulus. These results provide information that could lead to detailed characterization of initiated, premalignant cells in the adult brain and to a better understanding of glial carcinogenesis. PMID:11296486

Kokkinakis, D. M.; Watson, M. L.; Honig, L. S.; Rushing, E. J.; Mickey, B. E.; Schold, S. C.

2001-01-01

120

The plutonium-hydrogen reaction: SEM characterization of product morphology  

NASA Astrophysics Data System (ADS)

The product morphology of the hydrogen reaction with plutonium near the visibly observable reaction front, which separates the hydrided zone from the unreacted metal zone, has been investigated by scanning electron microscopy (SEM). Results indicate the existence of a mixed phase of metal and metal hydride, located some 20-30 ?m ahead of the visibly hydrided-zone. The mixed phase regions are often located next to a grain boundary network and exhibit rays of hydride advancing toward the unreacted metal regions. Analysis indicates that hydrogen transport and therefore the hydriding reaction are preferable along the grain boundary network and defects in the metal structure rather than through a homogeneous intragrain reaction. Product fracture and formation of small hydride particles during hydriding are likely results of such inhomogeneous growth.

Dinh, L. N.; McCall, S. K.; Saw, C. K.; Haschke, J. M.; Allen, P. G.; McLean, W.

2014-08-01

121

Micro-morphologic changes around biophysically-stimulated titanium implants in ovariectomized rats  

PubMed Central

Background Osteoporosis may present a risk factor in achievement of osseointegration because of its impact on bone remodeling properties of skeletal phsiology. The purpose of this study was to evaluate micro-morphological changes in bone around titanium implants exposed to mechanical and electrical-energy in osteoporotic rats. Methods Fifteen 12-week old sprague-dowley rats were ovariectomized to develop osteoporosis. After 8 weeks of healing period, two titanium implants were bilaterally placed in the proximal metaphyses of tibia. The animals were randomly divided into a control group and biophysically-stimulated two test groups with five animals in each group. In the first test group, a pulsed electromagnetic field (PEMF) stimulation was administrated at a 0.2 mT 4 h/day, whereas the second group received low-magnitude high-frequency mechanical vibration (MECHVIB) at 50 Hz 14 min/day. Following completion of two week treatment period, all animals were sacrificed. Bone sites including implants were sectioned, removed en bloc and analyzed using a microCT unit. Relative bone volume and bone micro-structural parameters were evaluated for 144 ?m wide peri-implant volume of interest (VOI). Results Mean relative bone volume in the peri-implant VOI around implants PEMF and MECHVIB was significantly higher than of those in control (P < .05). Differences in trabecular-thickness and -separation around implants in all groups were similar (P > .05) while the difference in trabecular-number among test and control groups was significant in all VOIs (P < .05). Conclusion Biophysical stimulation remarkably enhances bone volume around titanium implants placed in osteoporotic rats. Low-magnitude high-frequency MECHVIB is more effective than PEMF on bone healing in terms of relative bone volume. PMID:17634134

Akca, Kivanc; Sarac, Ebru; Baysal, Ugur; Fanuscu, Mete; Chang, Ting-Ling; Cehreli, Murat

2007-01-01

122

Synthesis, Characterization (Molecular-Morphological) and Theoretical Morphology Predictions of Poly(cyclohexadiene) Containing Linear Triblock Terpolymers  

SciTech Connect

The synthesis via anionic polymerization of six linear triblock terpolymers with various sequences of blocks such as PS (polystyrene), PB (polybutadiene), PI (polyisoprene) and PCHD (poly(1,3-cyclohexadiene)) is reported. The synthesis of the terpolymers was accomplished by the use of anionic polymerization with high vacuum techniques and sequential monomer addition. Molecular characterization of the samples was performed via size exclusion chromatography and membrane osmometry to measure polydispersity indices and the number-average molecular weights, respectively. Proton nuclear magnetic resonance spectroscopy was adopted to verify the type of microstructure for the polydienes as well as to calculate the molar composition. Structural characterization was performed via transmission electron microscopy and small angle X-ray scattering and several morphologies were observed including one which has not been reported previously. Real-space self-consistent field theory (SCFT) without a priori knowledge about the symmetry of the periodic structures was used to elucidate the thermodynamics of the synthesized triblock copolymers.

Kumar, Rajeev [ORNL; Dadmun, Mark D [ORNL; Sumpter, Bobby G [ORNL; Mays, Jimmy [ORNL; Avgeropoulos, Apostolos [University of Athens, Athens, Greece; Zafeiropoulos, N.E. [University of Athens, Athens, Greece; Misichoronis, K. [University of Athens, Athens, Greece; Rangou, S. [University of Athens, Athens, Greece; Ashcraft, E. [University of Tennessee, Knoxville (UTK)

2013-01-01

123

Os penis of the rat. II. Morphology of the mature bone.  

PubMed

A morphological description of the mature os penis and its related structures in the rat is presented. The description aims at being a natural introduction to studies of histomorphological and histochemical events during the development of the bone. The causal interest of this topic is due to a recently published observation of a rare reaction for presence of alkaline phosphatase in the proximally positioned growth cartilage of os penis. The study, thus, presents a systematical description of the position of os penis in relation to the soft tissue structures of glans penis, of gross morphology of the bone, of its periosteal covering and of the distribution of the bone types, which together form the mature bone. The observations result in an introduction of a systematical terminology, based on the Latin language. Furthermore, certain phenomena concerning a distally positioned cartilagenous process, and the distribution of bone tissue types in os penis are observed and discussed. Together with the phenomenon earlier mentioned these phenomena need further attention in future studies of the bone. PMID:546277

Vilmann, H; Vilmann, A

1979-01-01

124

Biochemical, Histopathological and Morphological Profiling of a Rat Model of Early Immune Stimulation: Relation to Psychopathology  

PubMed Central

Perinatal immune challenge leads to neurodevelopmental dysfunction, permanent immune dysregulation and abnormal behaviour, which have been shown to have translational validity to findings in human neuropsychiatric disorders (e.g. schizophrenia, mood and anxiety disorders, autism, Parkinson’s disease and Alzheimer’s disease). The aim of this animal study was to elucidate the influence of early immune stimulation triggered by systemic postnatal lipopolysaccharide administration on biochemical, histopathological and morphological measures, which may be relevant to the neurobiology of human psychopathology. In the present study of adult male Wistar rats we examined the brain and plasma levels of monoamines (dopamine, serotonin), their metabolites, the levels of the main excitatory and inhibitory neurotransmitters glutamate and ?-aminobutyric acid and the levels of tryptophan and its metabolites from the kynurenine catabolic pathway. Further, we focused on histopathological and morphological markers related to pathogenesis of brain diseases - glial cell activation, neurodegeneration, hippocampal volume reduction and dopaminergic synthesis in the substantia nigra. Our results show that early immune stimulation in adult animals alters the levels of neurotransmitters and their metabolites, activates the kynurenine pathway of tryptophan metabolism and leads to astrogliosis, hippocampal volume reduction and a decrease of tyrosine hydroxylase immunoreactivity in the substantia nigra. These findings support the crucial pathophysiological role of early immune stimulation in the above mentioned neuropsychiatric disorders. PMID:25602957

Kubesova, Anna; Tejkalova, Hana; Syslova, Kamila; Kacer, Petr; Vondrousova, Jana; Tyls, Filip; Fujakova, Michaela; Palenicek, Tomas; Horacek, Jiri

2015-01-01

125

A novel method for fast and statistically verified morphological characterization of filamentous fungi.  

PubMed

Along with productivity and physiology, morphological growth behavior is the key parameter in bioprocess design for filamentous fungi. Despite complex interactions between fungal morphology, broth viscosity, mixing kinetics, transport characteristics and process productivity, morphology is still commonly tackled only by empirical trial-and-error techniques during strain selection and process development procedures. In fact, morphological growth characteristics are investigated by computational analysis of only a limited number of pre-selected microscopic images or via manual evaluation of images, which causes biased results and does not allow any automation or high-throughput quantification. To overcome the lack of tools for fast, reliable and quantitative morphological analysis, this work introduces a method enabling statistically verified quantification of fungal morphology in accordance with Quality by Design principles. The novel, high-throughput method presented here interlinks fully automated recording of microscopic images with a newly developed evaluation approach reducing the need for manual intervention to a minimum. Validity of results is ensured by concomitantly testing the acquired sample for representativeness by statistical inference via bootstrap analysis. The novel approach for statistical verification can be equally applied as control logic to automatically proceed with morphological analysis of a consecutive sample once user defined acceptance criteria are met. Hence, analysis time can be reduced to an absolute minimum. The quantitative potential of the developed methodology is demonstrated by characterizing the morphological growth behavior of two industrial Penicillium chrysogenum production strains in batch cultivation. PMID:22587949

Posch, Andreas E; Spadiut, Oliver; Herwig, Christoph

2012-07-01

126

Morphological and Molecular Characterization of Meloidogyne mayaguensis Isolates from Florida  

PubMed Central

The discovery of Meloidogyne mayaguensis is confirmed in Florida; this is the first report for the continental United States. Meloidogyne mayaguensis is a virulent species that can reproduce on host cultivars bred for nematode resistance. The perineal patterns of M. mayaguensis isolates from Florida show morphological variability and often are similar to M. incognita. Useful morphological characters for the separation of M. mayaguensis from M. incognita from Florida are the male stylet length values (smaller for M. mayaguensis than M. incognita) and J2 tail length values (greater for M. mayaguensis than M. incognita). Meloidogyne mayaguensis values for these characters overlap with those of M. arenaria and M. javanica from Florida. Enzyme analyses of Florida M. mayaguensis isolates show two major bands (VS1-S1 phenotype) of esterase activity, and one strong malate dehydrogenase band (Rm 1.4) plus two additional weak bands that migrated close together. Their detection requires larger amounts of homogenates from several females. Amplification of two separate regions of mitochondrial DNA resulted in products of a unique size. PCR primers embedded in the COII and 16S genes produced a product size of 705 bp, and amplification of the 63-bp repeat region resulted in a single product of 322 bp. Nucleotide sequence comparison of these mitochondrial products together with sequence from 18S rDNA and ITS1 from the nuclear genome were nearly identical with the corresponding regions from a M. mayaguensis isolate from Mayaguez, Puerto Rico, the type locality of the species. Meloidogyne mayaguensis reproduced on cotton, pepper, tobacco, and watermelon but not on peanut. Preliminary results indicate the M. mayaguensis isolates from Florida can reproduce on tomato containing the Mi gene. Molecular techniques for the identification of M. mayaguensis will be particularly useful in cases of M. mayaguensis populations mixed with M. arenaria, M. incognita, and M. javanica, which are the most economically important root-knot nematode species in Florida, and especially when low (<25) numbers of specimens of these species are recovered from the soil. PMID:19262811

Brito, J.; Powers, T. O.; Mullin, P. G.; Inserra, R. N.; Dickson, D. W.

2004-01-01

127

Morphological and molecular characterization of Fusarium spp pathogenic to pecan tree in Brazil.  

PubMed

The occurrence of Fusarium spp associated with pecan tree (Carya illinoinensis) diseases in Brazil has been observed in recent laboratory analyses in Rio Grande do Sul State. Thus, in this study, we i) obtained Fusarium isolates from plants with disease symptoms; ii) tested the pathogenicity of these Fusarium isolates to pecan; iii) characterized and grouped Fusarium isolates that were pathogenic to the pecan tree based on morphological characteristics; iv) identified Fusarium spp to the species complex level through TEF-1? sequencing; and v) compared the identification methods used in the study. Fifteen isolates collected from the inflorescences, roots, and seeds of symptomatic plants (leaf necrosis or root rot) were used for pathogenicity tests. Morphological characterization was conducted using only pathogenic isolates, for a total of 11 isolates, based on the mycelial growth rate, sporulation, colony pigmentation, and conidial length and width variables. Pathogenic isolates were grouped based on morphological characteristics, and molecular characterization was performed by sequencing TEF-1? genes. Pathogenic isolates belonging to the Fusarium chlamydosporum species complex, Fusarium graminearum species complex, Fusarium proliferatum, and Fusarium oxysporum were identified based on the TEF-1? region. Morphological characteristics were used to effectively differentiate isolates and group the isolates according to genetic similarity, particularly conidial width, which emerged as a key morphological descriptor in this study. PMID:25501150

Lazarotto, M; Milanesi, P M; Muniz, M F B; Reiniger, L R S; Beltrame, R; Harakava, R; Blume, E

2014-01-01

128

Laser Patterning of Diamond. Part I. Characterization of Surface Morphology  

SciTech Connect

As the use of diamond as a material for electronic and research applications increases, methods of patterning diamond will be required. In this work, single- and polycrystalline synthetic diamond samples were exposed to laser beams of different energies, wavelengths, and pulse durations. The effects of this exposure were characterized using optical microscopy, scanning electron microscopy, and atomic force microscopy. The threshold ablation energy density for 266 nm radiation with {approx} 30 ps pulse duration was measured to be {approx} 14 J/cm{sup 2}. The threshold for {approx} 10 ns pulses at the same wavelength was similar, but the ablated area displayed larger surface damage. The surface damage and the threshold energy increase significantly for 532 and 1064 nm radiations. Ablation performed using 213 nm radiation produced the most uniform surface. Changes in the ablated surface are presented in detail.

Smedley, J.; Bohon, Jen; Wu, Qiong; Rao, Triveni

2009-06-24

129

Mycological Society of America Correspondence of Isozyme Characterization with Morphology in the Asexual Genus  

E-print Network

Mycological Society of America Correspondence of Isozyme Characterization with Morphology Source: Mycologia, Vol. 84, No. 1 (Jan. - Feb., 1992), pp. 12-25 Published by: Mycological Society of scholarship. For more information about JSTOR, please contact support@jstor.org. Mycological Society

Harrington, Thomas C.

130

MORPHOLOGICAL CHARACTERIZATION AND ANALYTICAL APPLICATION OF POLY(3,4-ETHYLENEDIOXYTHIOPHENE)-PRUSSIAN  

E-print Network

. Electrochemical behavior of the composite inorganic-organic coatings is based mainly on inorganic component redox Electrochemical in situ preparation and morphological characterization of inorganic redox material-ClO4). The composite coatings were prepared by electrochemical methods on platinum electrode chips

Boyer, Edmond

131

Morphologic and proteomic characterization of exosomes released by cultured extravillous trophoblast cells  

SciTech Connect

Exosomes represent an important intercellular communication vehicle, mediating events essential for the decidual microenvironment. While we have demonstrated exosome induction of pro-inflammatory cytokines, to date, no extensive characterization of trophoblast-derived exosomes has been provided. Our objective was to provide a morphologic and proteomic characterization of these exosomes. Exosomes were isolated from the conditioned media of Swan71 human trophoblast cells by ultrafiltration and ultracentrifugation. These were analyzed for density (sucrose density gradient centrifugation), morphology (electron microscopy), size (dynamic light scattering) and protein composition (Ion Trap mass spectrometry and western immunoblotting). Based on density gradient centrifugation, microvesicles from Sw71 cells exhibit a density between 1.134 and 1.173 g/ml. Electron microscopy demonstrated that microvesicles from Sw71 cells exhibit the characteristic cup-shaped morphology of exosomes. Dynamic light scattering showed a bell-shaped curve, indicating a homogeneous population with a mean size of 165 nm {+-} 0.5 nm. Ion Trap mass spectrometry demonstrated the presence of exosome marker proteins (including CD81, Alix, cytoskeleton related proteins, and Rab family). The MS results were confirmed by western immunoblotting. Based on morphology, density, size and protein composition, we defined the release of exosomes from extravillous trophoblast cells and provide their first extensive characterization. This characterization is essential in furthering our understanding of 'normal' early pregnancy.

Atay, Safinur [Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY (United States)] [Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY (United States); Gercel-Taylor, Cicek [Obstetrics, Gynecology and Women's Health, University of Louisville School of Medicine, Louisville, KY (United States)] [Obstetrics, Gynecology and Women's Health, University of Louisville School of Medicine, Louisville, KY (United States); Kesimer, Mehmet [Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States)] [Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC (United States); Taylor, Douglas D., E-mail: ddtaylor@louisville.edu [Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY (United States); Obstetrics, Gynecology and Women's Health, University of Louisville School of Medicine, Louisville, KY (United States)

2011-05-01

132

Comparative metabolism, thermoregulation and morphology in two populations of vlei rats (Otomys irroratus).  

PubMed

The Hogsback (32 degrees 33S 26 degrees 57E) and Alice (32 degrees 47S 26 degrees 50E), Eastern Cape, South Africa, are separated by only 24 km but by 1000 m in altitude and fall into different climatic regions. Thermal responses (energy expenditure and body temperature) to ambient temperature were measured in a population of vlei rats (Otomys irroratus) from each of the two localities. We predicted that animals from the colder Hogsback would show differences in their thermal physiology and morphology consistent with better cold-resistance. Basal metabolic rates of the Hogsback population were slightly, but not significantly, higher than the Alice population (23.9 J g-1 h-1 vs 22.3 J g-1 h-1), but the slope of the regression between energy expenditure and ambient temperature below the thermal neutral zone was significantly lower (-1.28 vs -1.60). Body temperature, although quite variable in both populations, was not significantly influenced by ambient temperature in the Hogsback population, whereas that of Alice animals was. Fur length was longer and relative size of the ears and tail was smaller in the Hogsback population, which probably accounted for the slightly lower minimum thermal conductance (1.79 J g-1 h-1 degree C-1 vs 1.91 J g-1 h-1 degree C-1) in the Hogsback population. Vlei rats from the two sites also have different karyotypes that correlate with climate but there is insufficient evidence at present to suggest that the different karyotypes and the physiological parameters measured are adaptive. PMID:10093904

Brown, C R; Everitt, V J; Baxter, R M

1999-02-01

133

Testicular morphology in spontaneously hypertensive rat model: oxidant status and stereological implications.  

PubMed

Studies by researchers suggest that reductions in blood flow to the testis could play an important role in the pathogenesis of male infertility. As this oxygen-dependent organ functions in a state of near anoxia, such a decrease in blood flow may very likely have profound effects on the tissue morphology that ultimately would predispose to various forms of hypo-spermatogenesis with consequent compromise in reproductive capability. With varying opinions expressed by experts as to the actual culprit or potential pathway and/or effects of pathophysiology of testicular haemodynamics, it still remains debatable whether the observed degenerative changes in testicular tissue are the result of major or minor reductions in flow or the consequence of other vascular pathologies or even extraneous factors. Again, increasing age and male gender have been identified as the single independent risk factors for the occurrence of cardiovascular pathologies with sexual dimorphism highly debated. The investigation of these factors occurring under hypertensive states using the spontaneously hypertensive rat (SHR) as an experimental model has attracted substantial attention in recent past. This review examines the relationships and potential morphologic changes in the testicular tissue under conditions of perturbations in blood flow as seen in the SHR with a view to the proper understanding of the role(s) of various factors that contributes to male subfertility. A suggestion to the use of stereological methods for quantitating various measurements in a highly active and dynamic structure like the testis with its arterial system has been added as this may facilitate a better understanding of the mechanisms implicated under hypertensive conditions. PMID:24471984

Azu, O O

2015-03-01

134

Blast exposure in rats with body shielding is characterized primarily by diffuse axonal injury.  

PubMed

Blast-induced traumatic brain injury (TBI) is the signature insult in combat casualty care. Survival with neurological damage from otherwise lethal blast exposures has become possible with body armor use. We characterized the neuropathologic alterations produced by a single blast exposure in rats using a helium-driven shock tube to generate a nominal exposure of 35 pounds per square inch (PSI) (positive phase duration ? 4 msec). Using an IACUC-approved protocol, isoflurane-anesthetized rats were placed in a steel wedge (to shield the body) 7 feet inside the end of the tube. The left side faced the blast wave (with head-only exposure); the wedge apex focused a Mach stem onto the rat's head. The insult produced ? 25% mortality (due to impact apnea). Surviving and sham rats were perfusion-fixed at 24 h, 72 h, or 2 weeks post-blast. Neuropathologic evaluations were performed utilizing hematoxylin and eosin, amino cupric silver, and a variety of immunohistochemical stains for amyloid precursor protein (APP), glial fibrillary acidic protein (GFAP), ionized calcium-binding adapter molecule 1 (Iba1), ED1, and rat IgG. Multifocal axonal degeneration, as evidenced by staining with amino cupric silver, was present in all blast-exposed rats at all time points. Deep cerebellar and brainstem white matter tracts were most heavily stained with amino cupric silver, with the morphologic staining patterns suggesting a process of diffuse axonal injury. Silver-stained sections revealed mild multifocal neuronal death at 24 h and 72 h. GFAP, ED1, and Iba1 staining were not prominently increased, although small numbers of reactive microglia were seen within areas of neuronal death. Increased blood-brain barrier permeability (as measured by IgG staining) was seen at 24 h and primarily affected the contralateral cortex. Axonal injury was the most prominent feature during the initial 2 weeks following blast exposure, although degeneration of other neuronal processes was also present. Strikingly, silver staining revealed otherwise undetected abnormalities, and therefore represents a recommended outcome measure in future studies of blast TBI. PMID:21449683

Garman, Robert H; Jenkins, Larry W; Switzer, Robert C; Bauman, Richard A; Tong, Lawrence C; Swauger, Peter V; Parks, Steven A; Ritzel, David V; Dixon, C Edward; Clark, Robert S B; Bayir, Hülya; Kagan, Valerian; Jackson, Edwin K; Kochanek, Patrick M

2011-06-01

135

Morphology and chemical characterization of Ti surfaces modified for biomedical applications.  

PubMed

The aim of the present work is to characterize in detail the chemical composition and morphology of titanium surfaces subjected to various environments. Modifications consisted of exposure of Ti to acidic, alkaline or polymer solutions. Such modifications result in chemical and/or morphological changes in the Ti surface. Special attention has been given to identifying the factors influencing cell adhesion and growth. SEM examinations provided morphological characterization of the Ti samples. Surface analytical techniques such as AES or XPS combined with Ar(+) ion sputtering allowed examination of the chemical properties of the Ti surface after chemical pretreatments and investigating the chemical composition of the Ti oxide layer. Raman spectroscopy investigations allowed determination of the crystalline phases of the Ti-oxide layers and characterization of the dextran-modified surface. The results show large differences in the morphology of Ti pretreated with different procedures whereas only minor differences in the chemistry of the surfaces were found. High-resolution Auger investigations have revealed that all the chemical modifications of Ti surfaces resulted in the formation of a titanium oxide layer. XPS confirmed that TiO(2) is the main component of the chemically modified Ti surface. The Raman spectroscopy investigations showed that the titanium surface with a dextran coating is rich in hydroxyl groups. All the surfaces investigated exhibit a hydrophilic character. The possible influence of various surface features on surface biocompatibility is discussed. PMID:17768086

Lewandowska, M; Roguska, A; Pisarek, M; Polak, B; Janik-Czachor, M; Kurzyd?owski, K J

2007-11-01

136

Cardiac oxidative stress determination and myocardial morphology after a single ecstasy (MDMA) administration in a rat model  

Microsoft Academic Search

Experimental and clinical data indicate that 3,4-methylenedioxy-N-methylamphetamine (MDMA) abuse can produce significant cardiovascular toxicity. A mechanism may be a direct toxic effect\\u000a of redox active metabolites of MDMA. To evaluate the effect of a single MDMA dose on cellular antioxidant defence system and\\u000a to investigate the morphology in male albino rats, total glutathione (GSH), oxidised glutathione (GSSG), ascorbic acid (AA),

Daniela Cerretani; Irene Riezzo; Anna Ida Fiaschi; Fabio Centini; Giorgio Giorgi; Stefano D’Errico; Carmela Fiore; Steven B. Karch; Margherita Neri; Cristoforo Pomara; Emanuela Turillazzi; Vittorio Fineschi

2008-01-01

137

A photothrombotic ring stroke model in rats with remarkable morphological tissue recovery in the region at risk  

Microsoft Academic Search

The photothrombotic ring stroke model with sustained underperfusion followed by late spontaneous reperfusion (Gu et al. 1999)\\u000a was employed to study its morphological consequences. The exposed crania of adult male Wistar rats were subjected to a ring-shaped\\u000a laser irradiation beam simultaneously with intravenous erythrosin B infusion. The ischemic volume was calculated from serial\\u000a sections throughout the ischemic lesions at 4,

WeiGang Gu; Thomas Brännström; Wei Jiang; Per Wester

1999-01-01

138

Effects of ageing on morphology, amylase release, cytosolic Ca 2+ signals and acyl lipids in isolated rat parotid gland tissue  

Microsoft Academic Search

Xerostomia (oral dryness sensation) is due to dryness of the oral cavity and it is more prevalent in the elderly. This study investigated the effect of ageing on parotid gland structure and function of control (2–6 months) and aged (12, 16–18 and 22–24 months) rats employing light microscopic, colorimetric, gas chromatographic and microspectrofluorimetric methods to investigate the morphological changes of

Sukhbinder Mahay; Jose A. Pariente; Ana I. Lajas; Ernest Adeghate; Carole E. Rolph; Jaipaul Singh

2004-01-01

139

Morphological and biochemical examination of Cosmos 1887 rat heart tissue. Part 1: Ultrastructure  

NASA Technical Reports Server (NTRS)

Morphological changes were observed in the left ventricle of rat heart tissue from animals flown on the Cosmos 1887 biosatellite for 12.5 days. These tissues were compared to the synchronous and vivarium control hearts. While many normal myofibrils were observed, others exhibited ultrastructural alterations, i.e., damaged and irregular-shaped mitochondria and generalized myofibrillar edema. Analysis of variance (ANOVA) of the volume density data revealed a statistically significant increase in glycogen and a significant decrease in mitochondria compared to the synchronous and vivarium controls. Point counting indicated an increase in lipid and myeloid bodies and a decrease in microtubules, but these changes were not statistically significant. In addition, the flight animals exhibited some patchy loss of protofibrils (actin and myosin filaments) and some abnormal supercontracted myofibrils that were not seen in the controls. This study was undertaken to gain insight into the mechanistic aspects of cardiac changes in both animals and human beings as a consequence of space travel. Cardiac hypotrophy and fluid shifts have been observed after actual or simulated weightlessness and raise concerns about the functioning of the heart and circulatory system during and after travel in space.

Philpott, D. E.; Popova, I. A.; Kato, K.; Stevenson, J.; Miquel, J.; Sapp, W.

1990-01-01

140

Preliminary morphological and biochemical changes in rat liver following postnatal exposure to sodium arsenite  

PubMed Central

The effects of sodium arsenite exposure on the hepatic maturation period of cellular and functional reorganization in developing rat livers were evaluated. Animals received intraperitoneal injections of sodium arsenite (1.5 mg/kg body weight) or distilled water on days 9 to 28 after birth. On day 29, the animals were sacrificed either by cervical dislocation or by perfusion fixation. The perfusion fixed liver tissue was processed for paraffin embedding, sectioning and hematoxylin and eosin staining. The fresh liver tissue was processed for cryo-sectioning followed by Sudan Black B staining and for biochemical estimation of reduced glutathione. Microscopic observation revealed comparable preserved hepatic lobular patterns and distributions of uninucleate and binucleate hepatocytes in the control and the experimental groups. The mean nuclear area and diameter of the hepatocytes was increased in the experimental group. Lipid droplet distribution pattern in Sudan Black B stained sections revealed higher staining intensity towards the centrilobular area in both groups. Semiquantitative estimation of staining intensity showed lower mean gray values in zone 3 than in zones 2 and 1 (suggestive of the setting in of the adult pattern) in both groups. The reduced glutathione levels in the liver tissue and the altered nuclear size of the hepatocytes in the experimental group suggested the impairment of morphological and biochemical processes induced by arsenic exposure during the postnatal period. PMID:23301191

Bhattacharya, Arnab; Mehra, Raj D.

2012-01-01

141

Morphology and Physiology of Excitatory Neurons in Layer 6b of the Somatosensory Rat Barrel Cortex  

PubMed Central

Neocortical lamina 6B (L6B) is a largely unexplored layer with a very heterogeneous cellular composition. To date, only little is known about L6B neurons on a systematic and quantitative basis. We investigated the morphological and electrophysiological properties of excitatory L6B neurons in the rat somatosensory barrel cortex using whole-cell patch-clamp recordings and simultaneous biocytin fillings. Subsequent histological processing and computer-assisted 3D reconstructions provided the basis for a classification of excitatory L6B neurons according to their structural and functional characteristics. Three distinct clusters of excitatory L6B neurons were identified: (C1) pyramidal neurons with an apical dendrite pointing towards the pial surface, (C2) neurons with a prominent, “apical”-like dendrite not oriented towards the pia, and (C3) multipolar spiny neurons without any preferential dendritic orientation. The second group could be further subdivided into three categories termed inverted, “tangentially” oriented and “horizontally” oriented neurons. Furthermore, based on the axonal domain two subcategories of L6B pyramidal cells were identified that had either a more barrel-column confined or an extended axonal field. The classification of excitatory L6B neurons provided here may serve as a basis for future studies on the structure, function, and synaptic connectivity of L6B neurons. PMID:22944531

Marx, Manuel; Feldmeyer, Dirk

2013-01-01

142

Morphological characterization of selected balloon films and its effects on balloon performances  

NASA Technical Reports Server (NTRS)

Morphological characterization of several polyethylene balloon films have been studied using various techniques. The objective is to determine, if any, differentiating structural or morphological features that can be related to the performance of these balloon film materials. The results of the study indicate that the films are composed of either linear low denstiy polyethylene (LLDPE) or low density polyethylene (LDPE). A selective examination of these data imply that films limited degree of branching and larger crystallites size (same % crystallinity) showed good mechanical properties that appear to correlate with their high level of success in balloon flights.

Said, Magdi A.

1994-01-01

143

An investigation into the reversibility of the morphological and cytokinetic changes seen in the small intestine of riboflavin deficient rats.  

PubMed Central

BACKGROUND: Impaired iron handling in riboflavin deficiency is thought to be partially a result of significant morphological and cytokinetic changes within the small intestine. AIMS: The aim of the study was to find out if the responses of the rat small intestine to riboflavin deficiency induced at weaning could be reversed upon repletion. SUBJECTS: 48 female weanling Wistar rats were used for the purpose of the study. METHODS: Rats were fed a riboflavin deficient diet or a complete control diet for a period of five weeks followed by a repletion period of up to three weeks. Rats were killed on day 0, 2, 7, or 21 of repletion. The duodenum was removed and fixed for subsequent analysis. RESULTS: Five weeks of riboflavin deficiency significantly changed the morphology and cytokinetics of the duodenum; the changes were not reversed within the 21 day repletion period despite biochemical evidence for a correction of the deficiency. CONCLUSIONS: The results show that the small intestine cannot readily recover from a period of riboflavin deficiency induced at weaning, supporting the notion that the weaning period is a critical time for gastrointestinal development and highlighting the importance of adequate nutrition during infancy. PMID:8991860

Williams, E A; Rumsey, R D; Powers, H J

1996-01-01

144

Relationship between abnormal sperm morphology induced by dietary zinc deficiency and lipid composition in testes of growing rats.  

PubMed

The present study investigated the effect of dietary Zn deficiency during sexual maturation on sperm integrity and testis phospholipid fatty acid composition. Male weanling Sprague-Dawley rats were randomised into four dietary groups for 3 weeks: Zn control (ZC; 30 mg Zn/kg); Zn marginally deficient (ZMD; 9 mg Zn/kg); Zn deficient (ZD; < 1 mg Zn/kg); pair fed (PF; 30 mg Zn/kg) to the ZD group. Morphology of cauda epididymal sperm and lipid profiles of testis phospholipids were analysed. The rats fed the ZD diet had a lower testis weight (P < 0.02). Seminal vesicles and prostate weight were also lower in the ZD and PF groups. Rats fed the ZD diet, but not the ZMD diet, had 34-35 % more abnormal spermatozoa and 24 % shorter sperm tail length than the ZC and PF rats (P < 0.001). Testis cholesterol concentration was higher in the ZD rats compared with the ZC and PF rats (P < 0.04). Testes were highly enriched with n-6 fatty acids by showing n-6 : n-3 fatty acid ratios of 27:1 in phosphatidylcholine (PC) and 23:1 in phosphatidylethanolamine (PE). The dominant fatty acid in testes was docosapentaenoic acid (22 : 5n-6), comprising 15 and 24 % of PC and PE, respectively. This fatty acid was significantly lower in the ZD rats, whereas 18 : 2n-6 was higher compared with the rats in the other diet groups. These results demonstrate that severe Zn deficiency adversely affects sperm integrity and modulates testis fatty acid composition by interrupting essential fatty acid metabolism. This suggests that Zn deficiency-associated abnormal testicular function is perhaps preceded by altered membrane fatty acid composition, especially of a major fatty acid, 22 : 5n-6. PMID:19222874

Merrells, Krystal J; Blewett, Heather; Jamieson, Jennifer A; Taylor, Carla G; Suh, Miyoung

2009-07-01

145

Trigonella foenum graecum seed extract protects kidney function and morphology in diabetic rats via its antioxidant activity.  

PubMed

Oxidative stress is involved in the development and progression of diabetic nephropathy (DN). Because Trigonella foenum graecum has been reported to have antidiabetic and antioxidative effects, we hypothesized that T foenum graecum seed aqueous extract (TE) restores the kidney function of diabetic rats via its antioxidant activity. Rats were fed diets enriched with sucrose (50%, wt/wt), lard (30%, wt/wt), and cholesterol (2.5%, wt/wt) for 8 weeks to induce insulin resistance. After a DN model was induced by streptozotocin, the rats were administered a low (440 mg/kg), medium (870 mg/kg), or high (1740 mg/kg) dose of TE by oral intragastric intubation for 6 weeks. In TE-treated DN rats, blood glucose, kidney/body weight ratio, serum creatinine, blood urea nitrogen, 24-hour content of urinary protein, and creatinine clearance were significantly decreased compared with nontreated DN rats. Diabetic rats showed decreased activities of superoxide dismutase and catalase, increased concentrations of malondialdehyde in the serum and kidney, and increased levels of 8-hydroxy-2'-deoxyguanosine in urine and renal cortex DNA. Treatment with TE restored the altered parameters in a dose-dependent manner. Furthermore, all of the ultramorphologic abnormalities in the kidney of diabetic rats, including the uneven thickening of the glomerular base membrane, were markedly ameliorated by TE treatment. We conclude that TE confers protection against functional and morphologic injuries in the kidneys of diabetic rats by increasing activities of antioxidants and inhibiting accumulation of oxidized DNA in the kidney, suggesting a potential drug for the prevention and therapy of DN. PMID:21840472

Xue, Wanli; Lei, Jing; Li, Xuanshe; Zhang, Ruijuan

2011-07-01

146

Characterization of p75{sup +} ectomesenchymal stem cells from rat embryonic facial process tissue  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Ectomesenchymal stem cells (EMSCs) were found to migrate to rat facial processes at E11.5. Black-Right-Pointing-Pointer We successfully sorted p75NTR positive EMSCs (p75{sup +} EMSCs). Black-Right-Pointing-Pointer p75{sup +} EMSCs up to nine passages showed relative stable proliferative activity. Black-Right-Pointing-Pointer We examined the in vitro multilineage potential of p75{sup +} EMSCs. Black-Right-Pointing-Pointer p75{sup +}EMSCs provide an in vitro model for tooth morphogenesis. -- Abstract: Several populations of stem cells, including those from the dental pulp and periodontal ligament, have been isolated from different parts of the tooth and periodontium. The characteristics of such stem cells have been reported as well. However, as a common progenitor of these cells, ectomesenchymal stem cells (EMSCs), derived from the cranial neural crest have yet to be fully characterized. The aim of this study was to better understand the characteristics of EMSCs isolated from rat embryonic facial processes. Immunohistochemical staining showed that EMSCs had migrated to rat facial processes at E11.5, while the absence of epithelial invagination or tooth-like epithelium suggested that any epithelial-mesenchymal interactions were limited at this stage. The p75 neurotrophin receptor (p75NTR), a typical neural crest marker, was used to select p75NTR-positive EMSCs (p75{sup +} EMSCs), which were found to show a homogeneous fibroblast-like morphology and little change in the growth curve, proliferation capacity, and cell phenotype during cell passage. They also displayed the capacity to differentiate into diverse cell types under chemically defined conditions in vitro. p75{sup +} EMSCs proved to be homogeneous, stable in vitro and potentially capable of multiple lineages, suggesting their potential for application in dental or orofacial tissue engineering.

Wen, Xiujie; Liu, Luchuan; Deng, Manjing; Zhang, Li; Liu, Rui; Xing, Yongjun; Zhou, Xia [Department of Stomatology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042 (China)] [Department of Stomatology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042 (China); Nie, Xin, E-mail: dr.xinnie@gmail.com [Department of Stomatology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042 (China)] [Department of Stomatology, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing 400042 (China)

2012-10-12

147

Morphological aspects of neuromuscular junctions and gene expression of nicotinic acetylcholine receptors (nAChRs) in skeletal muscle of rats with heart failure.  

PubMed

HF is syndrome initiated by a reduction in cardiac function and it is characterized by the activation of compensatory mechanisms. Muscular fatigue and dyspnoea are the more common symptoms in HF; these may be due in part to specific skeletal muscle myopathy characterized by reduced oxidative capacity, a shift from slow fatigue resistant type I to fast less fatigue resistant type II fibers and downregulation of myogenic regulatory factors (MRFs) gene expression that can regulate gene expression of nicotinic acetylcholine receptors (nAChRs). In chronic heart failure, skeletal muscle phenotypic changes could influence the maintenance of the neuromuscular junction morphology and nAChRs gene expression during this syndrome. Two groups of rats were studied: control (CT) and Heart Failure (HF), induced by a single intraperitoneal injection of monocrotaline (MCT). At the end of the experiment, HF was evaluated by clinical signs and animals were sacrificed. Soleus (SOL) muscles were removed and processed for morphological, morphometric and molecular NMJ analyses. Our major finding was an up-regulation in the gene expression of the alpha1 and epsilon subunits of nAChR and a spot pattern of nAChR in SOL skeletal muscle in this acute monocrotaline induced HF. Our results suggest a remodeling of nAChR alpha1 and epsilon subunit during heart failure and may provide valuable information for understanding the skeletal muscle myopathy that occurs during this syndrome. PMID:21928074

de Souza, Paula Aiello Tomé; Matheus, Selma Maria Michelin; Castan, Eduardo Paulino; Campos, Dijon Henrique Salomé; Cicogna, Antônio Carlos; Carvalho, Robson Francisco; Dal-Pai-Silva, Maeli

2011-12-01

148

Hemodynamic flow improves rat hepatocyte morphology, function, and metabolic activity in vitro  

PubMed Central

In vitro primary hepatocyte systems typically elicit drug induction and toxicity responses at concentrations much higher than corresponding in vivo or clinical plasma Cmax levels, contributing to poor in vitro-in vivo correlations. This may be partly due to the absence of physiological parameters that maintain metabolic phenotype in vivo. We hypothesized that restoring hemodynamics and media transport would improve hepatocyte architecture and metabolic function in vitro compared with nonflow cultures. Rat hepatocytes were cultured for 2 wk either in nonflow collagen gel sandwiches with 48-h media changes or under controlled hemodynamics mimicking sinusoidal circulation within a perfused Transwell device. Phenotypic, functional, and metabolic parameters were assessed at multiple times. Hepatocytes in the devices exhibited polarized morphology, retention of differentiation markers [E-cadherin and hepatocyte nuclear factor-4? (HNF-4?)], the canalicular transporter [multidrug-resistant protein-2 (Mrp-2)], and significantly higher levels of liver function compared with nonflow cultures over 2 wk (albumin ?4-fold and urea ?5-fold). Gene expression of cytochrome P450 (CYP) enzymes was significantly higher (fold increase over nonflow: CYP1A1: 53.5 ± 10.3; CYP1A2: 64.0 ± 15.1; CYP2B1: 15.2 ± 2.9; CYP2B2: 2.7 ± 0.8; CYP3A2: 4.0 ± 1.4) and translated to significantly higher basal enzyme activity (device vs. nonflow: CYP1A: 6.26 ± 2.41 vs. 0.42 ± 0.015; CYP1B: 3.47 ± 1.66 vs. 0.4 ± 0.09; CYP3A: 11.65 ± 4.70 vs. 2.43 ± 0.56) while retaining inducibility by 3-methylcholanthrene and dexamethasone (fold increase over DMSO: CYP1A = 27.33 and CYP3A = 4.94). These responses were observed at concentrations closer to plasma levels documented in vivo in rats. The retention of in vivo-like hepatocyte phenotype and metabolic function coupled with drug response at more physiological concentrations emphasizes the importance of restoring in vivo physiological transport parameters in vitro. PMID:23485712

Simmers, M. B.; Deering, T. G.; Berry, D. J.; Feaver, R. E.; Hastings, N. E.; Pruett, T. L.; LeCluyse, E. L.; Blackman, B. R.; Wamhoff, B. R.

2013-01-01

149

Characterization and control of fungal morphology for improved production performance in biotechnology.  

PubMed

Filamentous fungi have been widely applied in industrial biotechnology for many decades. In submerged culture processes, they typically exhibit a complex morphological life cycle that is related to production performance--a link that is of high interest for process optimization. The fungal forms can vary from dense spherical pellets to viscous mycelia. The resulting morphology has been shown to be influenced strongly by process parameters, including power input through stirring and aeration, mass transfer characteristics, pH value, osmolality and the presence of solid micro-particles. The surface properties of fungal spores and hyphae also play a role. Due to their high industrial relevance, the past years have seen a substantial development of tools and techniques to characterize the growth of fungi and obtain quantitative estimates on their morphological properties. Based on the novel insights available from such studies, more recent studies have been aimed at the precise control of morphology, i.e., morphology engineering, to produce superior bio-processes with filamentous fungi. PMID:22771505

Krull, Rainer; Wucherpfennig, Thomas; Esfandabadi, Manely Eslahpazir; Walisko, Robert; Melzer, Guido; Hempel, Dietmar C; Kampen, Ingo; Kwade, Arno; Wittmann, Christoph

2013-01-20

150

Effects of a Saturated Fat and High Cholesterol Diet on Memory and Hippocampal Morphology in the Middle-Aged Rat  

PubMed Central

Diets rich in cholesterol and/or saturated fats have been shown to be detrimental to cognitive performance. Therefore, we fed a cholesterol (2%) and saturated fat (hydrogenated coconut oil, Sat Fat 10%) diet to 16-month old rats for 8 weeks to explore the effects on the working memory performance of middle-aged rats. Lipid profiles revealed elevated plasma triglycerides, total cholesterol, HDL, and LDL for the Sat-Fat group as compared to an iso-caloric control diet (12% soybean oil). Weight gain and food consumption were similar in both groups. Sat-Fat treated rats committed more working memory errors in the water radial arm maze, especially at higher memory loads. Cholesterol, amyloid-? peptide of 40 (A?40) or 42 (A?42) residues, and nerve growth factor in cortical regions was unaffected, but hippocampal Map-2 staining was reduced in rats fed a Sat-Fat diet, indicating a loss of dendritic integrity. Map-2 reduction correlated with memory errors. Microglial activation, indicating inflammation and/or gliosis, was also observed in the hippocampus of Sat-Fat fed rats. These data suggest that saturated fat, hydrogenated fat and cholesterol can profoundly impair memory and hippocampal morphology. PMID:18560126

Granholm, Ann-Charlotte; Bimonte-Nelson, Heather A.; Moore, Alfred B.; Nelson, Matthew E.; Freeman, Linnea R.; Sambamurti, Kumar

2009-01-01

151

Effects of chronic administration of arachidonic acid on lipid profiles and morphology in the skeletal muscles of aged rats.  

PubMed

Arachidonic acid (20:4n-6, ARA) is a major component of the cell membrane, whereas ARA-derived eicosanoids are formed when cells are damaged. Aging is associated with an accretion of oxidative stress in skeletal muscles. In this study, we examined the effects of chronic administration (13 weeks) of ARA (240 mg/kg/day) on fatty acid composition, antioxidative status, and morphology of slow (soleus muscles) and fast (extensor digitorum longus muscles; EDL)-twitch muscles in aged rats (21 months old). The level of reactive oxygen species was higher in the EDL of ARA-administered rats than in that of control rats. ARA administration decreased the muscle cell volumes and increased the number of slow myosin heavy chain (MHC)-positive cells in the EDL. The relative content of MHC2X was increased whereas the relative content of MHC2B was decreased in the EDL of ARA-administered rats. These results suggest that ARA deposition in the fast-twitch muscle of aged rats reduced cell volume with an increase in oxidative stress. PMID:25128088

Inoue, Takayuki; Hashimoto, Michio; Katakura, Masanori; Tanabe, Yoko; Al Mamun, Abdullah; Matsuzaki, Kentaro; Otani, Hiroki; Shido, Osamu

2014-10-01

152

Changes in axonal physiology and morphology after chronic compressive injury of the rat thoracic spinal cord.  

PubMed

The spinal cord is rarely transected after spinal cord injury. Dysfunction of surviving axons, which traverse the site of spinal cord injury, appears to contribute to post-traumatic neurological deficits, although the underlying mechanisms remain unclear. The subpial rim frequently contains thinly myelinated axons which appear to conduct signals abnormally, although it is uncertain whether this truly reflects maladaptive alterations in conduction properties of injured axons during the chronic phase of spinal cord injury or whether this is merely the result of the selective survival of a subpopulation of axons. In the present study, we examined the changes in axonal conduction properties after chronic clip compression injury of the rat thoracic spinal cord, using the sucrose gap technique and quantitatively examined changes in the morphological and ultrastructural features of injured axonal fibers in order to clarify these issues. Chronically injured dorsal columns had a markedly reduced compound action potential amplitude (8.3% of control) and exhibited significantly reduced excitability. Other dysfunctional conduction properties of injured axons included a slower population conduction velocity, a longer refractory period and a greater degree of high-frequency conduction block at 200 Hz. Light microscopic and ultrastructural analysis showed numerous axons with abnormally thin myelin sheaths as well as unmyelinated axons in the injured spinal cord. The ventral column showed a reduced median axonal diameter and the lateral and dorsal columns showed increased median diameters, with evidence of abnormally large swollen axons. Plots of axonal diameter versus myelination ratio showed that post-injury, dorsal column axons of all diameters had thinner myelin sheaths. Noninjured dorsal column axons had a median myelination ratio (1.56) which was within the optimal range (1.43-1.67) for axonal conduction, whereas injured dorsal column axons had a median myelination ratio (1.33) below the optimal value. These data suggest that maladaptive alterations occur postinjury to myelin sheath thickness which reduce the efficiency of axonal signal transmission.In conclusion, chronically injured dorsal column axons show physiological evidence of dysfunction and morphological changes in axonal diameter and reduced myelination ratio. These maladaptive alterations to injured axons, including decrease in myelin thickness and the appearance of axonal swellings, contribute to the decreased excitability of chronically injured axons. These results further clarify the mechanisms underlying neurological dysfunction after chronic neurotrauma and have significant implications regarding approaches to augment neural repair and regeneration. PMID:11311546

Nashmi, R; Fehlings, M G

2001-01-01

153

Effect of traumatic occlusion on CGRP and SP immunoreactive nerve fibre morphology in rat molar pulp and periodontium.  

PubMed

Traumatic occlusion provides a trauma that affects the whole tooth and its supporting tissues. To study the effect of this trauma on CGRP and SP immunoreactive nerve morphology in pulp and periodontium, traumatic occlusion was induced in 2-months-old rats. The occlusal surface of the first maxillary molar in 30 rats were unilaterally raised 1 mm with a composite material. At different observation periods up to 30 days, the rats were transcardiacally perfused, the jaws demineralized, sectioned and processed for immunohistochemistry with the avidin-biotin-peroxidase method. Changes in nerve morphology, distribution and density in first and second molars and their supporting tissues were analyzed and compared in experimental (n = 30) and control rats (n = 14). Already after 5 days with traumatic occlusion, 22% of the experimental teeth had increased density of CGRP and SP immunoreactive nerves locally in gingiva, the periodontal ligament and the pulp, while in 15%, axonal proliferation and changed nerve morphology were found in the whole pulp (severe reaction). During a 20-day period, the pulpal nerve reactions progressed and included the whole pulp in 46% of the experimental teeth. The periodontal nerve responses were still localized only to the cervical and apical regions, and they remained local in these areas throughout the experimental periods. After 20 days the number of teeth with severe nerve changes seemed to decrease. The study shows that an unilateral change in occlusion of the first molar initiate nerve responses in the total molar dentition. In this experimental model the pulpal axons containing CGRP and SP reacted more serious to occlusal trauma than the nerves in the periodontium. The results indicate that the nerve changes in some cases might be transient. PMID:1373126

Kvinnsland, I; Heyeraas, K J

1992-01-01

154

Characterization and distribution of Reelin-positive interneuron subtypes in the rat barrel cortex.  

PubMed

GABAergic inhibitory interneurons (IN) represent a heterogeneous population with different electrophysiological, morphological, and molecular properties. The correct balance between interneuronal subtypes is important for brain function and is impaired in several neurological and psychiatric disorders. Here we show the data of 123 molecularly and electrophysiologically characterized neurons of juvenile rat barrel cortex acute slices, 48 of which expressed Reelin (Reln). Reln mRNA was exclusively detected in Gad65/67-positive cells but was found in interneuronal subtypes in different proportions: all cells of the adapting-Somatostatin (SST) cluster expressed Reln, whereas 63% of the adapting-neuropeptide Y (NPY, 50% of the fast-spiking Parvalbumin (PVALB), and 27% of the adapting/bursting-Vasoactive Intestinal Peptide (VIP) cluster were Reln-positive. Silhouette analysis revealed a high impact of the parameter Reln on cluster quality. By analyzing the co-localization of RELN immunoreactivity with those of different IN-markers, we found that RELN is produced layer-independently in SST-, NPY-, and NOS1-expressing INs, whereas co-localization of RELN and VIP was mostly absent. Of note, RELN co-localized with PVALB, predominantly in INs of layers IV/V (>30%). Our findings emphasize RELN's role as an important IN-marker protein and provide a basis for the functional characterization of Reln-expressing INs and its role in the regulation of inhibitory IN networks. PMID:23803971

Pohlkamp, Theresa; Dávid, Csaba; Cauli, Bruno; Gallopin, Thierry; Bouché, Elisabeth; Karagiannis, Anastassios; May, Petra; Herz, Joachim; Frotscher, Michael; Staiger, Jochen F; Bock, Hans H

2014-11-01

155

Neuropharmacokinetic characterization of lamotrigine after its acute administration to rats.  

PubMed

The purpose of this study is to characterize the neuropharmacokinetics of lamotrigine following a single intraperitoneal dose. Adult male Wistar rats were given lamotrigine dose of 5, 10, or 20 mg/kg. Blood and brain samples were obtained at predetermined times over 120 h and analyzed by HPLC. The overall characteristics of plasma curves were determined by noncompartmental analysis with WINNONLIN. The kinetic characterization of lamotrigine distribution between plasma and brain was performed by indirect numerical deconvolution with MULTI(FILT). A linear disposition kinetics was observed within 5-20 mg/kg. The lamotrigine concentrations in brain homogenate were approx. twofold higher than in plasma. The following pharmacokinetic parameters were obtained for lamotrigine 5, 10, and 20 mg/kg, respectively: clearance of distribution from plasma to brain normalized with the volume of the brain, CL/V(h(-1)) = 4.64, 2.47, 2.40; brain-to-plasma partition coefficient, P = 0.40, 0.37, 0.34; first-order transfer rate constant from the brain to the plasma, K(h(-1)) = 11.68, 6.68, 5.96; single-pass mean transit time in the brain, MTT(h) = 0.086, 0.150, 0.168. These results indicate that lamotrigine plasma levels may be good indicators of lamotrigine levels in the brain and that higher response intensities could be expected with higher doses of lamotrigine, since efficacious concentrations are maintained for a longer period. PMID:16273133

Castel-Branco, M M; Falcao, A C; Figueiredo, I V; Caramona, M M; Lanao, J M

2005-10-01

156

Effects of palm oil tocotrienol-rich fraction on biochemical and morphological alterations of liver in fenitrothion-treated rats.  

PubMed

Indiscriminate application of organophosphate (OP) pesticides has led to environmental pollution and severe health problems. The aim of the present study was to evaluate the effect of palm oil tocotrienol-rich fraction (TRF) on biochemical and morphological changes of the liver in rats treated with fenitrothion (FNT), a type of OP pesticide. A total of 28 male Sprague-Dawley rats were divided into four groups; control group, TRF-supplemented group, FNT-treated group and TRF+FNT group. TRF (200 mg/kg) was supplemented 30 minutes prior to FNT (20 mg/kg) administration, both orally for 28 consecutive days. Following 28 days of treatment, plasma biochemical changes and liver morphology were evaluated. The body and absolute liver weights were significantly elevated in TRF+FNT group compared to FNT group. TRF administration significantly decreased the total protein level and restored the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in TRF + FNT group. In contrast, total bilirubin level, ?-glutamyltranferase (GGT) and cholinesterase activity in TRF + FNT group did not significantly differ from FNT group. Administration of TRF also prevented FNT-induced morphological changes of liver as observed by electron microscope. In conclusion, TRF supplementation showed potential protective effect towards biochemical and ultrastructural changes in liver induced by FNT. PMID:25362611

Jayusman, Putri Ayu; Budin, Siti Balkis; Ghazali, Ahmad Rohi; Taib, Izatus Shima; Louis, Santhana Raj

2014-11-01

157

Characterization of a Novel Lysozyme-Like 4 Gene in the Rat  

PubMed Central

Lysozyme-like proteins (LYZLs) belong to the class of c-type lysozymes and are not well characterized in many species including the rat. In this study, using in silico and molecular biology techniques, we report the identification, cloning and characterization of rat Lyzl4 gene and also determine the expression pattern of Lyzl1, Lyzl3 and Lyzl6. The rat Lyzl genes were found to be distributed on three chromosomes and all of them retained the characteristic eight cysteine signature of c-type lysozyme. Homology modeling of rat LYZL4 indicated that its structure is similar to that of the mouse SLLP1. In the male reproductive tract of rat, Lyzl gene expression was confined to the testis. Lyzl1 and Lyzl4 were found to be expressed in tissues beyond the male reproductive tract, whereas Lyzl3 and Lyzl6 were not. Lyzl expression in the developing (10–60 day old) rats was androgen dependent in the testis. Immunodetection using antibodies against rat LYZL4 revealed the presence of LYZL4 protein in the germinal layer of the testes and on the sperm tail. Recombinant LYZL4 did not exhibit antibacterial, muramidase and isopeptidase activities characteristic to c-type lysozyme. To the best of our knowledge, for the first time we report the characterization of Lyzl genes in the rat. Results of our study indicate that rat LYZL proteins may have an important role in male reproductive tract function. PMID:22110709

Narmadha, Ganapathy; Muneswararao, Katakam; Rajesh, Angireddy; Yenugu, Suresh

2011-01-01

158

Biopharmaceutical Characterization of Nebulized Antimicrobial Agents in Rats: 2. Colistin  

PubMed Central

The purpose of this study was to investigate the pharmacokinetic properties of colistin following intrapulmonary administration of colistin sulfate in rats. Colistin was infused or delivered in nebulized form at a dose of 0.35 mg/kg of body weight in rats, and plasma drug concentrations were measured for 4 h after administration. Bronchoalveolar lavages (BAL) were also conducted at 0.5, 2, and 4 h after intravenous (i.v.) administration and administration via nebulized drug to estimate epithelial lining fluid (ELF) drug concentrations. Unbound colistin plasma concentrations at distribution equilibrium (2 h postdosing) were almost identical after i.v. infusion and nebulized drug inhalation. ELF drug concentrations were undetectable in BAL samples after i.v. administration, but they were about 1,800 times higher than unbound plasma drug levels at 2 h and 4 h after administration of the nebulized drug. Simultaneous pharmacokinetic modeling of plasma and ELF drug concentrations was performed with a model characterized by a fixed physiological volume of ELF (VELF), a passive diffusion clearance (QELF) between plasma and ELF, and a nonlinear influx transfer from ELF to the central compartment, which was assessed by reducing the nebulized dose of colistin by 10-fold (0.035 mg kg?1). The km was estimated to be 133 ?g ml?1, and the Vmax, in-to-Km ratio was equal to 2.5 × 10?3 liter h?1 kg?1, which was 37 times higher than the QELF (6.7 × 10?5 liter h?1 kg?1). This study showed that with the higher ELF drug concentrations after administration via nebulized aerosol than after intravenous administration, for antibiotics with low permeability such as colistin, nebulization offers a real potential over intravenous administration for the treatment of pulmonary infections. PMID:24798284

Gontijo, Aline Vidal Lacerda; Grégoire, Nicolas; Lamarche, Isabelle; Gobin, Patrice; Marchand, Sandrine

2014-01-01

159

Effect of Boswellia serrata gum resin on the morphology of hippocampal CA1 pyramidal cells in aged rat.  

PubMed

Experimental evidence indicates that administration of Boswellia resin, known as olibanum or Frankincense, increases memory power. It is reported that beta boswellic acid, the major component of Boswellia serrata gum resin, could enhance neurite outgrowth and branching in hippocampal neurons. We therefore studied whether Boswellia treatment produces morphological changes in the superior region of cornu ammonis (CA1) in aged rats. Sixteen male Wistar rats, 24 months of age, were randomly divided in experimental and control groups. The experimental group was orally administered Boswellia serrata gum resin (100 mg/kg per day for 8 weeks) and the control group received a similar volume of water. The Cavalieri principle was employed to estimate the volumes of CA1 hippocampal field, and a quantitative Golgi study was used to analysis of dendritic arborizations of CA1 pyramidal cells. Comparisons revealed that Boswellia-treated aged rats had greater volumes than control animals in stratum pyramidale and stratum radiatum lacunosum-moleculare. The neurons of CA1 in experimental rats had more dendritic segments (40.25 ± 4.20) than controls (30.9 ± 4.55), P = 0.001. The total dendritic length of CA1 neurons was approximately 20 % larger in the experimental group compared to control. Results also indicated that the aged rats treated with Boswellia resin had more numerical branching density in the apical dendrites of CA1 pyramidal neurons. The results of the present study show that long-term administration of Boswellia resin can attenuate age-related dendritic regression in CA1 pyramidal cells in rat hippocampus. PMID:24515442

Hosseini-Sharifabad, Mohammad; Esfandiari, Ebrahim

2015-01-01

160

Stasis and convergence characterize morphological evolution in eupolypod II ferns Michael A. Sundue1,* and Carl J. Rothfels,2  

E-print Network

Stasis and convergence characterize morphological evolution in eupolypod II ferns Michael A. Sundue rank remain underexplored in the ferns. The present studyseeksto addressthis gap through analysis of 79 morphological characters for 81 taxa, includ- ing representatives of all ten families of eupolypod II ferns

161

Biochemical and morphological studies on perivenous and periportal liver parenchymal cells from female rats isolated by digitonin-collagenase method.  

PubMed

Periportal (pp) or perivenous (pv) liver parenchymal cells from female adult Uje: WIST rats were isolated after retro- or antegrade digitonin infusion followed by collagenase perfusion in the opposite direction. The morphological results revealed a distinct acinar-related destruction of the pv- or pp-zone by digitonin. The remaining cells of the respective other zone showed a good structural maintenance. After subsequent conventional collagenase perfusion the yield, viability and structural integrity of the isolated hepatocytes were high. The zonal cell separation was indicated by significant differences in the pp marker glucose-6-phosphatase and the pv marker glutamine synthetase found in the isolated pp or pv cell populations. Under our experimental conditions including the use of female rats, the alanine aminotransferase and glutamate dehydrogenase as well as ethylmorphine N-demethylase and ethoxycoumarin O-deethylase activities were evenly distributed in both preparations. Under stimulating conditions the capacity for urea synthesis was similar in both pv and pp cells. PMID:1680746

Köhler, T; Müller, D; Franke, H; Machnik, G; Müller, D; Zimmermann, T

1991-01-01

162

N-methyl-D-aspartate receptor channel blockers prevent pentylenetetrazole-induced convulsions and morphological changes in rat brain neurons.  

PubMed

Alterations in inhibitory and excitatory neurotransmission play a central role in the etiology of epilepsy, with overstimulation of glutamate receptors influencing epileptic activity and corresponding neuronal damage. N-methyl-D-aspartate (NMDA) receptors, which belong to a class of ionotropic glutamate receptors, play a primary role in this process. This study compared the anticonvulsant properties of two NMDA receptor channel blockers, memantine and 1-phenylcyclohexylamine (IEM-1921), in a pentylenetetrazole (PTZ) model of seizures in rats and investigated their potencies in preventing PTZ-induced morphological changes in the brain. The anticonvulsant properties of IEM-1921 (5 mg/kg) were more pronounced than those of memantine at the same dose. IEM-1921 and memantine decreased the duration of convulsions by 82% and 37%, respectively. Both compounds were relatively effective at preventing the tonic component of seizures but not myoclonic seizures. Memantine significantly reduced the lethality caused by PTZ-induced seizures from 42% to 11%, and all animals pretreated with IEM-1921 survived. Morphological examination of the rat brain 24 hr after administration of PTZ revealed alterations in the morphology of 20-25% of neurons in the neocortex and the hippocampus, potentially induced by excessive glutamate. The expression of the excitatory amino acid transporter 1 protein was increased in the hippocampus of the PTZ-treated rats. However, dark neurons did not express caspase-3 and were immunopositive for the neuronal nuclear antigen protein, indicating that these neurons were alive. Both NMDA antagonists prevented neuronal abnormalities in the brain. These results suggest that NMDA receptor channel blockers might be considered possible neuroprotective agents for prolonged seizures or status epilepticus leading to neuronal damage. © 2014 Wiley Periodicals, Inc. PMID:25359451

Zaitsev, Aleksey V; Kim, Kira Kh; Vasilev, Dmitry S; Lukomskaya, Nera Ya; Lavrentyeva, Valeria V; Tumanova, Natalia L; Zhuravin, Igor A; Magazanik, Lev G

2015-03-01

163

Morphology of Rat Hippocampal CA1 Neurons Following Modified Two and Four-Vessels Global Ischemia Models  

PubMed Central

Background An appropriate animal model of ischemia stroke is essential for evaluation of different therapeutic methods. Two and four-vessel global ischemia models are one of the most common types of transient cerebral ischemia. Objectives In this study, the morphology of rat hippocampal CA1 neurons in modified models of two and four-vessel ischemia and reperfusion were evaluated. Materials and Methods In this study, 20 Wistar rats were randomly divided into five groups. In group 2 and 3, both common carotid arteries were occluded for 10 minutes in either 3 or 24 hours of reperfusions, respectively. In group 4 and 5, both common carotid and vertebral arteries were occluded for 10 minutes in either 3 or 24 hours of reperfusions, respectively. Group 1 as control, underwent the whole surgery without any arteries occlusion. Hippocampi of the rats in all groups were processed and tissue sections were stained using the Nissl method. The morphology of CA1 neurons were studied under a light microscope and compared different groups. Results In all groups ischemic changes were apparently observed in hippocampus CA1 neurons. In two-vessel occlusion model, after 3 and 24 hours of reperfusions, ischemic cells accounted for 14.9% and 23.2%, respectively. In four-vessel occlusion model, after 3 and 24 hours of reperfusions, ischemic cells accounted for 7.6% and 44.9% (P < 0.0001), respectively. Conclusions Modified four-vessel occlusion model resulted in significant ischemic changes after 24 hours of reperfusion in CA1 neurons of rat hippocampus. PMID:24693522

Atlasi, Mohammad Ali; Naderian, Homayoun; Noureddini, Mahdi; Fakharian, Esmaeil; Azami, Abolfazl

2013-01-01

164

Integral-geometry characterization of photobiomodulation effects on retinal vessel morphology.  

PubMed

The morphological characterization of quasi-planar structures represented by gray-scale images is challenging when object identification is sub-optimal due to registration artifacts. We propose two alternative procedures that enhances object identification in the integral-geometry morphological image analysis (MIA) framework. The first variant streamlines the framework by introducing an active contours segmentation process whose time step is recycled as a multi-scale parameter. In the second variant, we used the refined object identification produced in the first variant to perform the standard MIA with exact dilation radius as multi-scale parameter. Using this enhanced MIA we quantify the extent of vaso-obliteration in oxygen-induced retinopathic vascular growth, the preventative effect (by photobiomodulation) of exposure during tissue development to near-infrared light (NIR, 670 nm), and the lack of adverse effects due to exposure to NIR light. PMID:25071966

Barbosa, Marconi; Natoli, Riccardo; Valter, Kriztina; Provis, Jan; Maddess, Ted

2014-07-01

165

Integral-geometry characterization of photobiomodulation effects on retinal vessel morphology  

PubMed Central

The morphological characterization of quasi-planar structures represented by gray-scale images is challenging when object identification is sub-optimal due to registration artifacts. We propose two alternative procedures that enhances object identification in the integral-geometry morphological image analysis (MIA) framework. The first variant streamlines the framework by introducing an active contours segmentation process whose time step is recycled as a multi-scale parameter. In the second variant, we used the refined object identification produced in the first variant to perform the standard MIA with exact dilation radius as multi-scale parameter. Using this enhanced MIA we quantify the extent of vaso-obliteration in oxygen-induced retinopathic vascular growth, the preventative effect (by photobiomodulation) of exposure during tissue development to near-infrared light (NIR, 670 nm), and the lack of adverse effects due to exposure to NIR light. PMID:25071966

Barbosa, Marconi; Natoli, Riccardo; Valter, Kriztina; Provis, Jan; Maddess, Ted

2014-01-01

166

A comprehensive physico-chemical, mineralogical and morphological characterization of Indian mineral wastes.  

PubMed

This paper provides a comprehensive characterization of mineral waste such as fly ash, bottom ash, slag and construction demolition (C&D) collected from four different thermal power plants, three steel plants and three C&D waste generation sites in India. To determine utilisation potential and environmental concerns, as received fly ash, bottom ash, slag and C&D waste were analysed for physico-chemical, mineralogical and morphological properties. The physico-chemical properties analysed include pH, moisture content, acid insoluble residue, loss on ignition(LOI), carbon content, fineness, chloride content, sulphate content, reactive silica content, XRF and heavy metal analysis. Morphological and mineralogical characteristics were investigated using scanning electron microscopy-energy dispersive X-ray. Particle size distribution was obtained using particle size analyser. The material analysed has different compositions and were selected with a view to determine their suitability for different applications in cement and concrete industry and for further research studies. PMID:23255170

Gedam, Vidyadhar V; Jha, Rajesh; Labhasetwar, Pawan; Engelsen, Christian J

2013-08-01

167

Morphological and functional manifestations of rat adrenal-cortex response to sodium bromide administration under hypodynamic stress  

NASA Technical Reports Server (NTRS)

Functional and morphological manifestations of adrenal cortex response to hypodynamia (2-hr immobilization on an operating table) under the influence of bromine preparations were studied. The sodium bromide was administered intraperitoneally in 100, 250, and 500 mg/kg doses once and repeatedly during ten days. The adrenal gland was evaluated functionally by ascorbic acid and cholesterol content and morphologically by coloring it with hematoxylin-eosin and Sudans for lipid revealing at freezing. Results are displayed in two tables and microphotographs. They are summarized as follows: the bromine weakens the functional state of the adrenal cortex in intact rats, causing changes similar to those under stress. During immobilization combined with preliminary bromine administration, a less pronounced stress reaction is noticeable.

Kirichek, L. T.; Zholudeva, V. I.

1979-01-01

168

GLUTAMATE NEUROTOXICITY IN THE DEVELOPING RAT COCHLEA: PHYSIOLOGICAL AND MORPHOLOGICAL APPROACHES  

EPA Science Inventory

The neurotoxic effects of exogenous glutamate were studied in the rat cochlea. lutamate-treated rats (4g/kg/day ip, postnatal days 2 through 9) exhibited electrophysiologically-measured elevations in high frequency thresholds usually associated with hair cell loss in the basal re...

169

Hemodynamic characterization of chronic bile duct-ligated rats: effect of pentobarbital sodium  

SciTech Connect

Systemic and splanchnic hemodynamics of the chronic bile duct-ligated rat were characterized by radioactive microspheres. Conscious and pentobarbital sodium-anesthetized, bile duct-ligated and sham-operated rats had cardiac output and regional organ blood flows determined. The conscious bile duct-ligated rat compared with the sham-operated showed a hyperdynamic circulation with an increased cardiac output and portal tributary blood flow. Pentobarbital sodium anesthesia induced marked hemodynamic changes in both sham-operated and bile duct-ligated rats. The latter group was especially sensitive to its effects; thus, comparison of cardiac output and portal tributary blood flow between anesthetized bile duct-ligated and sham-operated rats showed no significant differences. The authors conclude that the rat with cirrhosis due to chronic bile duct ligation is an excellent model for hemodynamic investigations but should be studied in the conscious state, since pentobarbital sodium anesthesia eliminated the hyperdynamic circulation.

Lee, S.S.; Girod, C.; Braillon, A.; Hadengue, A.; Lebrec, D.

1986-08-01

170

Morphology-controlled synthesis and characterization of urchin-like CdS and nanowire  

NASA Astrophysics Data System (ADS)

Novel urchin-like CdS was synthesized via a facile solvothermal route without any assistant agent. The as-prepared samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, high-resolution transmission electron, and photoluminescence spectrophotometer. Based on time-resolved experiments, a possible growth mechanism of 3D urchin-like CdS microspheres was initially proposed. Furthermore, morphology control of CdS was achieved by adjusting the quantity addition of TGA to obtain the 1D CdS nanowires.

Cao, Weiwei; Gai, Hongde; Zhu, Bo; Wu, Yimin; Zhang, Chunlei

2012-08-01

171

HemoHIM improves ovarian morphology and decreases expression of nerve growth factor in rats with steroid-induced polycystic ovaries.  

PubMed

Estradiol valerate (EV)-induced polycystic ovaries (PCOs) in rats cause the anovulation and cystic ovarian morphology. We investigated whether treatment with HemoHIM influences the ovarian morphology and the expression of nerve growth factor (NGF) in an EV-induced PCO rat model. PCO was induced by a single intramuscular injection of EV (4 mg, dissolved in sesame oil) in adult cycling rats. HemoHIM was either administered orally (100 mg/kg of body weight/day) for 35 consecutive days or injected intraperitoneally (50 mg/kg of body weight) every other day after EV injection. Ovarian morphology was almost normalized, and NGF was normalized in the PCO + HemoHIM group. HemoHIM lowered the high numbers of antral follicles and increased the number of corpora lutea in PCOs. The results are consistent with a beneficial effect of HemoHIM in the prevention and treatment of PCO syndrome. PMID:20041792

Kim, Sung Ho; Lee, Hae June; Kim, Joong Sun; Moon, Changjong; Kim, Jong Choon; Bae, Chun Sik; Park, Hae Ran; Jung, Uhee; Jo, Sung Kee

2009-12-01

172

Growth and development of Pygidiopsis summa in rats and mice with a supplementary note on its morphological characters.  

PubMed

The growth and development of Pygidiopsis summa were studied in experimental rats and mice, and a special reference was given to its morphological characters differed from the type species, P. genata. The metacercariae were obtained from young mullets (Mugil sp.), and total 21 rats and mice infected each with 1,000 metacercariae. Worms of various ages of infection, from 3 to 28 days, were subjected to a microscopic observation. The worms grew rapidly and remarkably in size up to 10 days of infection, to become 0.53-0.82 mm long and 0.31-0.39 mm wide, but nearly stopped the growth thereafter. Their genital organs developed more rapidly and fully matured within 3-5 days. At 3 days several eggs were found in uterus. The presence of two groups of small spines, 5-6 on the right and 7-9 on the left side of the genital apparatus, was a new finding in this study and considered a distinct character of P. summa. The morphology of ventral sucker and intestinal ceca was also different from P. genata. This study confirms the validity of the species, P. summa. PMID:12886108

Chai, Jong Yil; Seo, Byong Seol; Lee, Soon Hyung; Hong, Sung Tae

1986-06-01

173

Radiosensitivity study and radiation effects on morphology characterization of grey oyster mushroom Pleurotus sajor-caju  

NASA Astrophysics Data System (ADS)

Radiosensitive dosage and morphology characterization of irradiated grey oyster mushroom Pleurotus sajor-caju by gamma rays was investigated due to effects of irradiation. In order to establish the effect, mycelium of P. sajor-caju was irradiated by gamma rays at dose 0.1 to 8.0 kGy with dose rate 0.227 Gy sec-1. The irradiation of mycelia was carried out at the radiation facility in Malaysian Nuclear Agency. The radiosensitivity study was performed by evaluating the percentage of survival irradiated mycelia. The lethal dose of the mycelium P. sajor-caju was determined at 4.0 kGy and LD50 to be equal at 2.2 kGy. The radiation effects on morphology were evaluated based on growth rate of irradiated mycelia, mycelia types, colonization period on substrate, morphology of fruit bodies and yields. The results shown growth rate of irradiated mycelium was slightly lower than the control and decreased as the dose increased. Irradiation was found can induced the primordia formation on PDA and the BE of irradiated seed is higher than to control. The irradiation is proven to be useful for generating new varieties of mushroom with commercial value to the industry.

Rashid, Rosnani Abdul; Daud, Fauzi; Senafi, Sahidan; Awang, Mat Rasol; Mohamad, Azhar; Mutaat, Hassan Hamdani; Maskom, Mohd Meswan

2014-09-01

174

Testicular morphology of male rats exposed to Phaleria macrocarpa (Mahkota dewa) aqueous extract  

PubMed Central

Objective(s): This study was designed to investigate the effect of Phaleria macrocarpa aqueous extract (PM) on spermatogenesis by observing the histological changes of testes in adult male rats. Materials and Methods: PM was prepared by boiling the dried slices of P. macrocarpa fruits followed by filtering, centrifugation and freeze-drying to obtain the powder form. Eighteen Sprague Dawley adult male rats were divided into three groups (six in each group), designated as treatment (240 mg/kg PM), negative control (distilled water) and positive control (4mg/kg testosterone) and administered via intragastric gavage for seven weeks. In the sixth week of supplementation period, each male rat was introduced to five female rats. Afterward, all rats were sacrificed and the testes were removed for histological studies. Results: PM significantly increased the number of cell and the thickness of seminiferous tubules of male rats (P<0.05). However, there was no significant effect on the volume and size of testes. The mean of spermatogonia cells numbers of PM groups differed significantly from the negative and positive groups (P<0.05). Conclusion: PM showed potential value as an attractive alternative for improving sexual strength by increasing the number of spermatogonia cell and the thickness of the seminiferous tubules. Perhaps, PM could be suggested to be one of the herbal remedies that can improve men fertility. The results may have some clinical implication in the management of infertility. PMID:24967068

Parhizkar, Saadat; Zulkifli, Suriani Binti; Dollah, Mohammad Aziz

2014-01-01

175

[Morphological changes in the transplanted rat kidney under conditions of minor and major histocompatibility differences between donor and recipient].  

PubMed

Morphological changes in transplanted kidney were studied in 4 groups of rats with different histocompatibility differences between donor and recipient: 1. syngenetic differences, 2. differences in the main histocompatibility system H-1, 3. differences in the H-1 as well as in the subsidiary non-H-1 systems, 4. differences in the non-H-1 systems. -- In all the kidneys transplanted from a newly developed congenetic strain BP.1N to inbred rats of the BN strain (with differences in the non-H-1 systems) rejection developed in 2 to 3 weeks with manifestations of giant-cell interstitial nephritis with gradual destruction and phagocytosis of cortical tubules probably due to the production of antibodies against the basal membranes of tubules. -- In the paralel group with differences in the non-H-1 systems of BP into BN-1B, destroyed after 30 days, there were -- in addition to moderate acute rejection -- hypercellular glomerules with electrodense deposits in the mesangium seen as a manifestation of immuno-complex glomerulonephritis. Analogical glomerular changes without rejection were also fond in a control group of longer surviving syngenetic rats. PMID:7002326

Stejskal, J; Kren, V; Pávková, L

1980-05-01

176

Protective Effects of Co-Administration of Gallic Acid and Cyclosporine on Rat Myocardial Morphology Against Ischemia/Reperfusion  

PubMed Central

Background: Irreversible myocardial ischemic injury begins 20 minutes after the onset of coronary occlusion. Then the infarcted cells show signs of necrosis and death. Objectives: This study investigated the effects of co-administration of Gallic acid (antioxidant) with cyclosporine (mitochondrial permeability transition pore [mPTP] inhibitor) on myocardial morphology of rats during ischemia and reperfusion. Materials and Methods: Fifty-four male Wistar rats (250-300 g), were randomly divided into 9 groups: sham, control (Ca received saline, 1 mL/kg, Cb: perfused with cyclosporine CsA 0.2 µM), 3 groups pretreated with Gallic acid in saline (G1a:7.5, G2a:15, and G3a: 30 mg/kg/day, and gavage daily for 10 days, n = 6), and the other three groups were pretreated with Gallic acid then perfused using CsA, (G1b:7.5, G2b:15, and G3b: 30 mg/kg/day) at the first 13 minutes of reperfusion period. After 10 days pretreatment, the rat hearts were isolated and transferred to Langendorff apparatus and exposed to 30 minutes ischemia following 60 minutes reperfusion. Afterward, the hearts were preserved in 10% formalin for histological studies at the end of the experiment. Finally, hematoxylin and eosin and Masson’s trichrome staining techniques were used for evaluating the changes in myocardial architecture, degradation of myofibers, and collagen integrity. The differences were analyzed using Pearson test. Results: Cell degenerative changes, pyknotic nuclei, contraction bands, edema, and loosening of collagen in between muscle fibers were observed during ischemia-reperfusion. Myocardial architecture and cellular morphology were recovered in co-administration groups, especially in (Gallic acid 15 mg/kg + CsA, P < 0.001). Conclusions: The results suggest the important role of the antioxidant system potentiation in the prevention of myocardial damage.

Dianat, Mahin; Sadeghi, Najmeh; Badavi, Mohammad; Panahi, Marziyeh; Taheri Moghadam, Mahin

2014-01-01

177

Arterial morphology responds differently to Captopril then N-acetylcysteine in a monocrotaline rat model of pulmonary hypertension  

NASA Astrophysics Data System (ADS)

Pulmonary hypertension (PH) is an incurable condition inevitably resulting in death because of increased right heart workload and eventual failure. PH causes pulmonary vascular remodeling, including muscularization of the arteries, and a reduction in the typically large vascular compliance of the pulmonary circulation. We used a rat model of monocrotaline (MCT) induced PH to evaluated and compared Captopril (an angiotensin converting enzyme inhibitor with antioxidant capacity) and N-acetylcysteine (NAC, a mucolytic with a large antioxidant capacity) as possible treatments. Twenty-eight days after MCT injection, the rats were sacrificed and heart, blood, and lungs were studied to measure indices such as right ventricular hypertrophy (RVH), hematocrit, pulmonary vascular resistance (PVR), vessel morphology and biomechanics. We implemented microfocal X-ray computed tomography to image the pulmonary arterial tree at intravascular pressures of 30, 21, 12, and 6 mmHg and then used automated vessel detection and measurement algorithms to perform morphological analysis and estimate the distensibility of the arterial tree. The vessel detection and measurement algorithms quickly and effectively mapped and measured the vascular trees at each intravascular pressure. Monocrotaline treatment, and the ensuing PH, resulted in a significantly decreased arterial distensibility, increased PVR, and tended to decrease the length of the main pulmonary trunk. In rats with PH induced by monocrotaline, Captopril treatment significantly increased arterial distensibility and decrease PVR. NAC treatment did not result in an improvement, it did not significantly increase distensibility and resulted in further increase in PVR. Interestingly, NAC tended to increase peripheral vascular density. The results suggest that arterial distensibility may be more important than distal collateral pathways in maintaining PVR at normally low values.

Molthen, Robert; Wu, Qingping; Baumgardt, Shelley; Kohlhepp, Laura; Shingrani, Rahul; Krenz, Gary

2010-03-01

178

Characterization of 3D joint space morphology using an electrostatic model (with application to osteoarthritis)  

NASA Astrophysics Data System (ADS)

Joint space morphology can be indicative of the risk, presence, progression, and/or treatment response of disease or trauma. We describe a novel methodology of characterizing joint space morphology in high-resolution 3D images (e.g. cone-beam CT (CBCT)) using a model based on elementary electrostatics that overcomes a variety of basic limitations of existing 2D and 3D methods. The method models each surface of a joint as a conductor at fixed electrostatic potential and characterizes the intra-articular space in terms of the electric field lines resulting from the solution of Gauss’ Law and the Laplace equation. As a test case, the method was applied to discrimination of healthy and osteoarthritic subjects (N = 39) in 3D images of the knee acquired on an extremity CBCT system. The method demonstrated improved diagnostic performance (area under the receiver operating characteristic curve, AUC > 0.98) compared to simpler methods of quantitative measurement and qualitative image-based assessment by three expert musculoskeletal radiologists (AUC = 0.87, p-value = 0.007). The method is applicable to simple (e.g. the knee or elbow) or multi-axial joints (e.g. the wrist or ankle) and may provide a useful means of quantitatively assessing a variety of joint pathologies.

Cao, Qian; Thawait, Gaurav; Gang, Grace J.; Zbijewski, Wojciech; Reigel, Thomas; Brown, Tyler; Corner, Brian; Demehri, Shadpour; Siewerdsen, Jeffrey H.

2015-02-01

179

Characterization of 3D joint space morphology using an electrostatic model (with application to osteoarthritis).  

PubMed

Joint space morphology can be indicative of the risk, presence, progression, and/or treatment response of disease or trauma. We describe a novel methodology of characterizing joint space morphology in high-resolution 3D images (e.g. cone-beam CT (CBCT)) using a model based on elementary electrostatics that overcomes a variety of basic limitations of existing 2D and 3D methods. The method models each surface of a joint as a conductor at fixed electrostatic potential and characterizes the intra-articular space in terms of the electric field lines resulting from the solution of Gauss' Law and the Laplace equation. As a test case, the method was applied to discrimination of healthy and osteoarthritic subjects (N = 39) in 3D images of the knee acquired on an extremity CBCT system. The method demonstrated improved diagnostic performance (area under the receiver operating characteristic curve, AUC > 0.98) compared to simpler methods of quantitative measurement and qualitative image-based assessment by three expert musculoskeletal radiologists (AUC = 0.87, p-value = 0.007). The method is applicable to simple (e.g. the knee or elbow) or multi-axial joints (e.g. the wrist or ankle) and may provide a useful means of quantitatively assessing a variety of joint pathologies. PMID:25575100

Cao, Qian; Thawait, Gaurav; Gang, Grace J; Zbijewski, Wojciech; Reigel, Thomas; Brown, Tyler; Corner, Brian; Demehri, Shadpour; Siewerdsen, Jeffrey H

2015-02-01

180

The decreased expression of mitofusin-1 and increased fission-1 together with alterations in mitochondrial morphology in the kidney of rats with chronic fluorosis may involve elevated oxidative stress.  

PubMed

This study was designed to characterize changes in the expression of mitofusin-1 (Mfn1) and fission-1 (Fis1), as well as in mitochondrial morphology in the kidney of rats subjected to chronic fluorosis and to elucidate whether any mitochondrial injury observed is associated with increased oxidative stress. Sixty Sprague-Dawley (SD) rats were divided randomly into 3 groups of 20 each, i.e., the untreated control group (natural drinking water containing <0.5mg fluoride/L), the low-fluoride group (drinking water supplemented with 10mg fluoride/L, prepared with NaF) and the high-fluoride group (50mg fluoride/L), and treated for 6 months. Thereafter, renal expression of Mfn1 and Fis1 at both the protein and mRNA levels was determined by immunohistochemistry and real-time PCR, respectively. In addition, the malondiadehyde (MDA) was quantitated by the thiobarbituric acid procedure and the total antioxidative capability (T-AOC) by a colorimetric method. The morphology of renal mitochondria was observed under the transmission electron microscope. In the renal tissues of rats with chronic fluorosis, expression of both Mfn1 protein and mRNA was clearly reduced, whereas that of Fis1 was elevated. The level of MDA was increased and the T-AOC lowered. Swollen or fragmented mitochondria in renal cells were observed under the electronic microscope. These findings indicate that chronic fluorosis can lead to the abnormal mitochondrial dynamics and changed morphology in the rat kidney, which in mechanism might be induced by a high level of oxidative stress in the disease. PMID:24958380

Qin, Shuang-Li; Deng, Jie; Lou, Di-Dong; Yu, Wen-Feng; Pei, Jinjing; Guan, Zhi-Zhong

2015-01-01

181

Characterization of renal hyperemia in portal hypertensive rats  

SciTech Connect

In anesthetized sham-operated control (C) and portal vein stenosed (PVS) rats, renal blood flow (RBF) was measured with radioactive microspheres on days 2, 4, 6, 8, and 10 following surgery. On day 2, only a small increase in RBF (19%) was produced in PVS versus C rats. However, by day 4, a significant increase in RBF (35%) was observed in PVS versus C animals. By day 6, the renal hyperemia in PVS rats reached a maximal value that was 42% higher than in C rats. Thereafter (on days 8 and 10), the renal hyperemia remained at the maximal value. In a separate group of 10-day PVS rats, glucagon antiserum failed to attenuate the 44% increase in RBF observed in PVS versus C rats. Radioimmunoassay of C and PVS plasma (10-day samples) revealed that vasoactive intestinal polypeptide, substance P, cholecystokinin/gastrin, neurotensin, pancreatic polypeptide, beta-endorphin, and peptide histidine-isoleucine amide are not elevated in arterial plasma of PVS rats. These data indicate that the renal hyperemia induced by chronic portal hypertension is manifested within 4 days after the hypertensive insult. Our studies also suggest that at least 9 blood-borne gastrointestinal peptides are not directly involved in the renal response to portal vein stenosis.

Premen, A.J.; Banchs, V.; Go, V.L.W.; Benoit, J.N.; Granger, D.N.

1986-03-01

182

Morphological types of horizontal cell in rodent retinae: a comparison of rat, mouse, gerbil, and guinea pig.  

PubMed

Retinal horizontal cells of four rodent species, rat, mouse, gerbil, and guinea pig were examined to determine whether they conform to the basic pattern of two horizontal cell types found in other mammalian orders. Intracellular injections of Lucifer-Yellow were made to reveal the morphologies of individual cells. Immunocytochemistry with antisera against the calcium-binding proteins calbindin D-28k and parvalbumin was used to assess population densities and mosaics. Lucifer-Yellow injections showed axonless A-type and axon-bearing B-type horizontal cells in guinea pig, but revealed only B-type cells in rat and gerbil retinae. Calbindin immunocytochemistry labeled the A- and B-type populations in guinea pig, but only a homogeneous regular mosaic of cells with B-type features in rat, mouse, and gerbil. All calbindin-immunoreactive horizontal cells in the latter species were also parvalbumin-immunoreactive; comparison with Nissl-stained retinae showed that both antisera label all of the horizontal cells. Taken together, the data from cell injections and the population studies provide strong evidence that rat, mouse, and gerbil retinae have only one type of horizontal cell, the axon-bearing B-type, whereas the guinea pig has both A- and B-type cells. Thus, at least three members of the family Muridae differ from other rodents and deviate from the proposed mammalian scheme of horizontal cell types. The absence of A-type cells is apparently not linked to any peculiarities in the photoreceptor populations, and there is no consistent match between the topographic distributions of the horizontal cells and those of the cone photoreceptors or ganglion cells across the four rodent species. However, the cone to horizontal cell ratio is rather similar in the species with and without A-type cells. PMID:8038125

Peichl, L; González-Soriano, J

1994-01-01

183

Architectural characterization of organotypic cultures of H400 and primary rat keratinocytes.  

PubMed

Organotypic epithelial structures can be cultured using primary or immortalized keratinocytes. However, there has been little detailed quantitative histological characterization of such cultures in comparison with normal mucosal architecture. The aim of this study is to identify morphological markers of tissue architecture that can be used to monitor tissue structure, maturation, and differentiation and to enable quantitative comparison of organotypic cultures (OCs) with normal oral mucosa. OCs of oral keratinocytes [immortalized H400 or primary rat keratinocytes (PRKs)] were generated using the three scaffolds of de-epidermalized dermis (DED), polyethylene terephthalate (PET), and collagen gels for up to 14 days. Cultures and normal epithelium were analyzed immunohistochemically and by using the semi-quantitative reverse transcriptase polymerase chain reaction (sq-RT-PCR) for E-cadherin, desmoglein-3, plakophilin, involucrin, cytokeratins-1, -5, -6, -10, -13, and Ki67. The epithelial thickness of OCs was measured in stained sections using image processing. Histological analysis revealed that air-liquid interface (ALI) cultures generated stratified organotypic epithelial structures by 14-days. The final thickness of these cultures as well as the degree of maturation/stratification (including stratum corneum formation) varied significantly depending on the scaffold used. For certain scaffolds, the immunohistochemical profiles obtained recapitulated those of normal oral epithelium indicating comparable in vitro differentiation and proliferation. In conclusion, quantitative microscopy approaches enabled unbiased architectural characterization of OCs. The scaffold materials used in the present study (DED, collagen type-I and PET) differentially influenced cell behavior in OCs of oral epithelia. H400 and PRK OCs on DED at the ALI demonstrated similar characteristics in terms of gene expression and protein distribution to the normal tissue architecture. PMID:22733453

Khan, Erum; Shelton, Richard M; Cooper, Paul R; Hamburger, John; Landini, Gabriel

2012-12-01

184

Genetic and phenotypic characterization of a Japanese wild-derived DOB/Oda rat strain.  

PubMed

Wild-derived rat strains can provide novel genome resources that are not available in standard laboratory strains. Genetic backgrounds of wild-derived strains can facilitate effective genetic linkage analyses and often modulate the expression of mutant phenotypes. Here we describe the development and characterization of a new inbred rat strain, DOB/Oda, from wild rats (Rattus norvegicus) captured in Shitara, Aichi, Japan. Phenotype analysis of 109 parameters revealed that the DOB/Oda rats had small body weight, preference for darkness, and high locomotor activity compared with the rat strains in the National BioResource Project for the Rat (NBRP-Rat) database. Genome analysis with 357 SSLP markers identified DOB/Oda-specific alleles in 70 markers. The percentage of SSLP markers that showed polymorphism between the DOB/Oda strain and any of 132 laboratory strains from NBRP-Rat varied from 89 to 95 %. The polymorphic rate (average of the values of the percentage) for the DOB/Oda strain was 91.6 %, much higher than the rates for available wild-derived strains such as the Brown Norway rat. A phylogenic tree constructed with DOB/Oda and all the strains in NBRP-Rat showed that the DOB/Oda strain localized within the wild rat groups, apparently separate from the laboratory strains. Together, these findings indicated that the DOB/Oda rat has a unique genome that is not available in the laboratory strains. Therefore, the new DOB/Oda strain will provide an important genome resource that will be useful for designing genetic experiments and for the discovery of genes that modulate mutant phenotypes. PMID:23896813

Kuramoto, Takashi; Inoue, Satoko; Neoda, Yuki; Yamasaki, Ken-ichi; Hashimoto, Ryoko; Mashimo, Tomoji; Oda, Sen-ichi; Serikawa, Tadao

2013-08-01

185

Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility  

PubMed Central

Background In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility. Results Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v) or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process), the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse) to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between neighboring cell walls, as well as by changes in the inner cell wall structure, such as damaging, hole formation and loss of mechanical resistance, facilitating liquid and enzyme access to crystalline cellulose. Conclusions The results presented herewith show the efficiency of the proposed method for improving the enzymatic digestibility of sugarcane bagasse and provide understanding of the pretreatment action mechanism. Combining the different techniques applied in this work warranted thorough information about the undergoing morphological and chemical changes and was an efficient approach to understand the morphological effects resulting from sample delignification and its influence on the enhanced hydrolysis results. PMID:22122978

2011-01-01

186

Heterogeneous rotational responsiveness in 6-hydroxydopamine-denervated rats: pharmacological and neurochemical characterization  

Microsoft Academic Search

Qualitative differences in pharmacological responsiveness to various types of dopamine agonists have been reported in rats that have undergone unilateral 6-hydroxydopamine (6-OHDA)-induced denervation of the nigro-striatal pathway. The present experiments further characterize these differences, pharmacologically and neurochemically. Rats were classified as having high rotational sensitivity (0.03 mg\\/kg SC apomorphine sufficient to induce more than 100 rotations\\/20 min) or low sensitivity

Jeffrey M. Liebman; Richard Gerber; Nancy R. Hall; C. Anthony Altar

1988-01-01

187

Effects of ulinastatin administered at different time points on the pathological morphologies of the lung tissues of rats with hyperthermia  

PubMed Central

Hyperthermia not only directly induces cell injury of body tissues, but also causes the body to release large amounts of inflammatory mediators and cells with extensive biological activities to induce a systemic inflammatory response and immune dysfunction. Thus, hyperthermia causes systemic inflammatory response syndrome, aggravating injuries to various organs. This study aimed to observe the effects of ulinastatin (UTI) administered at different time points on the cellular morphologies of the lung tissues of rats with systemic hyperthermia. A total of 40 male Sprague Dawley rats were randomly divided into five groups: The normal control group (C group), the hyperthermia group without medication (H group), the hyperthermia and UTI pre-treatment group (HU group), the group treated with UTI at 1 h after hyperthermia (HU1 group), and the group treated with UTI at 2 h after hyperthermia (HU2 group). The systemic hyperthermia rat model was established in a heating chamber with a biological oxygen supply. For the HU, HU1 and HU2 groups, UTI (5×104 U/kg) was administered at different time points. For the C and H groups, an equivalent volume of normal saline was administered. During heating, the respiratory frequency and rectal temperature were measured and recorded once every 30 min. After 2.5 h of heating, the wet/dry weight (W/D) ratio of the lung tissues of the rats was measured. Additionally, the cellular morphologies of the lung tissues were observed under light and electron microscopes. The respiratory frequencies and lung tissue W/D ratios of the rats in the various hyperthermia groups were significantly higher than those of the rats in the C group (all P<0.05). The respiratory frequencies and lung tissue W/D values of the HU and HU1 groups were significantly lower than those of the H group (all P<0.05). Under the light microscope, the bronchial surrounding tissues of the HU and HU1 groups were loose, and the majority of the pulmonary alveolar structures were normal; the H and HU2 groups presented a number of changes, including pulmonary interstitial hyperemia, alveolar epithelial swelling and emphysema. Under the electron microscope, it was observed in the type II epithelial cells of the pulmonary alveoli of the H group that the mitochondria were swollen, the cell ridges were shortened, the microvilli were thin and increased, and the alveolar wall was thickened. Also, an increased number of infiltrating neutrophils were visible. In addition, the type II epithelial cells of the HU2 group also presented these changes to different extents and the changes in the HU and HU1 groups were the mildest. These results indicate that the early application of UTI relieves edema and the extent of cell injury of the lung tissue in rats with systemic hyperthermia. PMID:24926355

QIN, ZAI-SHENG; TIAN, PEI; WU, XIA; YU, HONG-MEI; GUO, NA

2014-01-01

188

CHARACTERIZATION OF RESPIRATORY DISEASE IN RATS FOLLOWING NEONATAL INOCULATION WITH A RAT-ADAPTED INFLUENZA VIRUS  

EPA Science Inventory

Neonatal F344 rats were infected with a rat-adapted influenza virus (RAIV) as a potential model to study the combined effects of early life viral respiratory infection with air pollutant dosimetry and toxic responses, as well as on the development of respiratory disease and incre...

189

MORPHOLOGICAL EFFECTS OF PROLONGED EXPOSURE TO OZONE AND SULFURIC ACID AEROSOL ON THE RAT LUNG  

EPA Science Inventory

The purpose of this study was to determine the pulmonary effects of a combination of ozone (0.5 ppm) and sulfuric acid aerosol (1 mg/cu. m.) and to assess the possibility of interactive effects. Groups of Sprague-Dawley rats were continously exposed to the pollutants, either indi...

190

Morphological, molecular and biological characterization of Mehdinema alii (Nematoda: Diplogasterida) from the decorated cricket (Gryllodes sigillatus).  

PubMed

The nematode Mehdinema alii was recovered from the decorated cricket Gryllodes sigillatus (Walker). Morphometric comparisons are presented from 3 populations. The nematode is characterized by dense arrays of spines on the cuticle of the anterior half of the body and a highly elongate, tubular stoma with a dorsal denticle in the glottoid region. Females have a protruding vulva. Young females are amphidelphic, but the anterior ovary disappears in older females bearing multiple developing juveniles. The male is monorchic with asymmetrically placed genital papillae, distally fused spicules, and a highly complex gubernaculum bearing 2 cuticularized thorns that protrude through a separate, postcloacal opening. Adult nematodes are located primarily in the hindgut, whereas juveniles or dauers occur mainly in the genital chamber of both male and female crickets. Male crickets are significantly more likely to be infected than females. This male-biased infection may be linked to the venereal transmission mechanism of the dauers. Although morphologically unusual in many respects, placement of M. alii in Diplogasterida is supported by both the morphology of the anterior digestive tract as well as analysis of its 18S rDNA sequence. These sequence data suggest that M. alii groups most closely with members of the Cylindrocorporidae. PMID:10647037

Luong, L T; Platzer, E G; De Ley, P; Thomas, W K

1999-12-01

191

Controlled synthesis, characterization and photocatalytic activity of BiPO4 nanostructures with different morphologies  

NASA Astrophysics Data System (ADS)

The synthesis of bismuth phosphate (BiPO4) nanostructures with various morphologies and phases was explored under ultrasound irradiation and hydrothermal process. Powder x-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Vis diffuse reflectance spectroscopy (DRS) were used to characterize the BiPO4 samples. The effects of ultrasound irradiation and hydrothermal conditions on the phases and morphologies of the BiPO4 samples were studied, and the growth mechanisms of the 1D structure were investigated. The different BiPO4 samples exhibited different optical properties and photocatalytic activities for the degradation of methyl blue (MB) under UV light irradiation. The experimental results suggest that the high photocatalytic activity of the sample prepared under hydrothermal conditions is due to a low electron and hole recombination rate and the high potential of the photogenerated holes in the valence band. The practicality of this BiPO4 photocatalyst was validated for the degradation of MB in environmental and industrial wastewater samples, which demonstrated the advantages of its high photocatalytic activity.

Cheng, Lang-Wei; Tsai, Jui-Chien; Huang, Tzu-Yun; Huang, Chang-Wei; Unnikrishnan, Binesh; Lin, Yang-Wei

2014-04-01

192

Morphological and molecular characterization of the causal agent of downy mildew on Quinoa (Chenopodium quinoa).  

PubMed

Downy mildew is an economically important and widespread disease in quinoa (Chenopodium quinoa) growing areas. Although in many studies Peronospora farinosa is most commonly regarded as the causal agent of the disease, identification and classification of the pathogen remain still uncertain due to its taxonomic confusion. Thirty-six Peronospora isolates from quinoa with different geographic origins including Argentina, Bolivia, Denmark, Ecuador, and Peru were morphologically and molecularly compared with Peronospora species from other Chenopodium species. The morphology of three herbarium specimens was similar to that of P. variabilis, which originated from C. album, characterized by flexuous to curved ultimate branchlets and pedicellated conidia. Phylogenetic analysis based on ITS rDNA sequences also placed the quinoa pathogen within the same clade as P. variabilis. Within the ITS rDNA sequences of the quinoa pathogens, two base substitutions were found, which separated the majority of the Danish isolates from isolates from South America, but no sequence difference was found among the isolates from different cultivars of quinoa. The present results indicate that the pathogen responsible for the quinoa downy mildew is identical to Peronospora variabilis and that it should not be lumped with P. farinosa as claimed previously by most studies. PMID:20101524

Choi, Young-Joon; Danielsen, Solveig; Lübeck, Mette; Hong, Seung-Beom; Delhey, Rolf; Shin, Hyeon-Dong

2010-05-01

193

A Morphological and Quantitative Characterization of Early Floral Development in Apple (Malus × domestica Borkh.)  

PubMed Central

Apple is an important crop and a focus of research worldwide. However, some aspects of floral commitment and morphogenesis remain unclear. A detailed characterization of bourse shoot apex development was undertaken to provide a framework for future genetic, molecular and physiological studies. Eight morphologically distinct stages of shoot apex development, prior to winter dormancy, were defined. Based on measurements of meristem diameter, two stages of vegetative development were recognized. Vegetative meristems were flat, and either narrow (stage 0) or broad (stage 1). Pronounced doming of the apex marked stage 2. During stage 3, the domed meristem initiated four to six lateral floral meristems and subtending bracts before converting to a terminal floral meristem (stage 4). The terminal floral meristem proceeded directly with bractlet and sepal initiation, while lateral floral meristems initiated bractlets (stage 5). Sepal initiation began on the basal lateral flower (stage 6) and continued in an acropetal direction until all floral meristems had completed sepal initiation (stage 7). In this study, only stage 0 and stage 7 apices were observed in dormant buds, indicating that stages 1–6 are transient. The results suggest that broadening of the apex (stage 1) is the first morphological sign of commitment to flowering. PMID:12805080

FOSTER, TOSHI; JOHNSTON, ROBYN; SELEZNYOVA, ALLA

2003-01-01

194

Morphological and Molecular Characterization of a Fungus, Hirsutella sp., Isolated from Planthoppers and Psocids in Argentina  

PubMed Central

A mycosed planthopper, Oliarus dimidiatus Berg (Hemiptera: Cixiidae), and two psocids, Heterocaecilius sp. (Psocodea: Pseudocaeciliidae) and Ectopsocus sp. (Ectopsocidae), were collected from Los Hornos and La Plata, Buenos Aires, Argentina between February and September 2007. Observations of mycelia growing on the host revealed that the putative fungal parasite had synnemata supporting monophialidic conidiogenous cells. Likewise, in vitro fungal cultures presented characteristics typical of the fungus Hirsutella citriformis Speare (Ascomycota: Hypocreales: Clavicipitaceae). The identity of the isolated fungi characterized based on morphological aspects was complemented by means of the internal transcribed spacer sequences. The sequences of both isolates were highly homologous to those of Cordyceps sp. (Fries) Link and Ophiocordyceps sinensis (Berkely) G.H. Sung, J.M. Sung, Hywel-Jones, and Spatafora (Ophiocordycipitaceae). We additionally confirmed that both isolates had the ability to infect and kill adults of Delphacodes kuscheli Fennah (Hemiptera: Delphacidae) after 10 days. Therefore, based on the morphology of the isolated fungi, their ribosomal internal transcribed spacer sequence, and their ability to parasite insects, we conclude that the fungi isolated belong to the genus Hirsutella and might have biotechnological potential. PMID:23885970

Toledo, Andrea V.; Simurro, María E.; Balatti, Pedro A.

2013-01-01

195

Effects of diet on experimentally induced intestinal ulcers in rats: morphology and tissue leukotrienes.  

PubMed Central

The effects of dietary pretreatment on longitudinal ulcers of the intestine induced by indomethacin given intracolonically were investigated in rats. The rats were pretreated with either standard diet or liquid meals. Intracolonic indomethacin (24 mg/kg/day) given for two days produced longitudinal ulcers and small scattered ulcers in the small intestine in the control rats that were receiving standard pelleted formula. Three days pretreatment with one of two types of liquid meals, low residual diet (LRD) or elemental diet (ED), significantly reduced the incidence (3% in ED group and 0% in the LRD group) and the length of the longitudinal ulcers in the small intestine. The caecum was affected in each dietary pretreatment group (67% in controls, 80% in LRD group, and 69% in ED group). Colonic ulcers that were located in a longitudinal fashion were found in 42% of LRD group, while these ulcers were less frequently found in the ED group (13%) and controls (0%). Development of ulcers in the caecum and in the colon of rats in ED and LRD groups was more delayed than that of small intestinal ulcers of control rats. In another experiment, pretreatment by ED significantly increased colonic tissue leukotriene B4 concentration when compared with that of controls. These findings suggest that the site of experimental enteropathy induced by indomethacin given intracolonically can be modified by dietary pretreatment. This animal model can be available for investigating differences in the pathophysiology of enteropathy according to the site of involvement. Images Figure 2 Figure 4 Figure 6 PMID:7926906

Matsumoto, T; Iida, M; Kuroki, F; Hizawa, K; Koga, H; Fujishima, M

1994-01-01

196

Morphologic, cytometric and functional characterization of the common octopus (Octopus vulgaris) hemocytes.  

PubMed

The hemocytes of Octopus vulgaris were morphologically and functionally characterized. Light and electron microscopy (TEM and SEM), and flow cytometry analyses revealed the existence of two hemocyte populations. Large granulocytes showed U-shaped nucleus, a mean of 11.6 ?m±1.2 in diameter with basophilic granules, polysaccharide and lysosomic deposits in the cytoplasm. Small granulocytes measured a mean of 8.1 ?m±0.7 in diameter, and have a round nucleus occupying almost the entire cell and few or not granules in the cytoplasm. Flow cytometry analysis showed that large granulocytes are the principal cells that develop phagocytosis of latex beads (rising up to 56%) and ROS after zymosan stimulation. Zymosan induced the highest production of both ROS and NO. This study is the first tread towards understanding the O. vulgaris immune system by applying new tools to provide a most comprehensive morpho-functional study of their hemocytes. PMID:24296436

Castellanos-Martínez, S; Prado-Alvarez, M; Lobo-da-Cunha, A; Azevedo, C; Gestal, C

2014-05-01

197

Short and long-term effects of a neonatal low-protein diet in rats on the morphology of the larynx  

Microsoft Academic Search

ObjectiveThe aim of this study was to investigate the short- and long-term effects of a maternal low-protein diet during lactation on offspring laryngeal morphology. Our hypothesis was that a neonatal low-protein diet during the critical period of development alters micro- and macroscopic structures of the larynx in adult rats.

Iracema Hermes Pires-de-Mélo; Flávia Wanderley dos Reis; Lívia Silva Luz; Silvania Tavares Paz; Hilton Justino Silva; Sandra Lopes Souza; Carol Góis Leandro

2009-01-01

198

Laboratory Investigations Intrauterine Exposure to a Maternal Low Protein Diet Reduces Adult Bone Mass and Alters Growth Plate Morphology in Rats  

Microsoft Academic Search

Epidemiological studies suggest that poor growth during fetal life and infancy is associated with decreased bone mass in adulthood. However, these observations have not, to date, been corroborated in animal models. To address this issue we evaluated the influence of maternal protein restriction on bone mass and growth plate morphology among the adult offspring, using a rat model. Maternal protein

G. Mehta; H. I. Roach; S. Langley-Evans; P. Taylor; R. O. C. Oreffo; A. Aihie-Sayer

199

The brachial plexus branches to the pectoral muscles in adult rats: morphological aspects and morphometric normative data  

PubMed Central

Animal models provide an important tool to investigate the pathogenesis of neuromuscular disorders. In the present study, we analyze fiber composition of the brachial plexus branches to the pectoral muscles: the medial anterior thoracic nerve (MATN) and the lateral anterior thoracic nerve (LATN). The morphological and morphometric characteristics and the percentage of motor fibers within each nerve are here reported, adding information to microscopic anatomy knowledge of the rat brachial plexus. As control, we employed the quadriceps nerve, commonly used for the evaluation of motor fibers at hindlimbs. We demonstrated that the MATN and the LATN are predominantly composed of large motor fibers and therefore could be employed to evaluate the peripheral nervous system (PNS) involvement at forelimbs in neurological diseases models, predominantly affecting the motor fiber compartment. PMID:23087618

Riva, Nilo; Domi, Teuta; Lopez, Ignazio Diego; Triolo, Daniela; Fossaghi, Andrea; Dina, Giorgia; Podini, Paola; Comi, Giancarlo; Quattrini, Angelo

2012-01-01

200

Characterization of Crystallographic Texture and Intra-Grain Morphology in Cross-Rolled Tantalum  

NASA Astrophysics Data System (ADS)

We present a detailed characterization of crystallographic texture and in-grain morphology in high purity Tantalum (Ta) during cross-rolling. A Ta disk with random initial texture was rolled to a total reduction of 50 pct in four equal steps, with the disk being rotated by 90 deg around the normal direction (ND) after every rolling step. Samples were cut along ND and were characterized using electron backscatter diffraction (EBSD), before and after the final deformation. Through-thickness texture heterogeneity was observed in the deformed disk, with an increase in <111> and <100> volume fraction parallel to ND from the surface toward the disk mid-section. The deformed texture of the mid-section of the disk (i.e., experiencing limited shear) was found to have a strong ?-fiber and a weak ?-fiber with presence of only {100} <110> texture component. From the grain-scale EBSD study, the deformed grain morphology was found to be one of the three major types: (a) un-fragmented, (b) fragmented-mottled, and (c) fragmented-banded or elongated deformation bands. The un-fragmented grains had <111> parallel to ND, with <110> parallel to the rolling direction or the transverse direction. The fragmented-mottled grains had multiple sub-grain orientations. The two major bands in the fragmented-banded grains had its <100> and <111> parallel to ND. In addition, they shared a common <110> with a misorientation of 30 deg. Through our knowledge of the known stable components formed during rolling of Ta, it was feasible to explain the orientations of such un-fragmented and fragmented-banded grains.

Bhattacharyya, Abhishek; Knezevic, Marko; Abouaf, Marc

2014-12-01

201

Morphological characterization of lineages within the calcified tropical seaweed genus Halimeda (Bryopsidales, Chlorophyta)  

Microsoft Academic Search

phylogenetic assessments have uncovered five principal monophyletic lineages within the genus. In the present study we define these lineages morphologically. We gathered morphological data from specimens used in the molecular analyses as well as from collections having a similar morphology and originating from the same geographical region. Starting from the lineages and their morphological synapomorphies, we define and illustrate five

HEROEN V ERBRUGGEN; W IEBE H. C. F. K OOISTRA

2004-01-01

202

Characterization of Dystrophin Deficient Rats: A New Model for Duchenne Muscular Dystrophy  

PubMed Central

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. PMID:25310701

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

203

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

PubMed

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. PMID:25310701

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

204

Creation and preliminary characterization of a Tp53 knockout rat  

PubMed Central

SUMMARY The tumor suppressor TP53 plays a crucial role in cancer biology, and the TP53 gene is the most mutated gene in human cancer. Trp53 knockout mouse models have been widely used in cancer etiology studies and in search for a cure of cancer with some limitations that other model organisms might help overcome. Via pronuclear microinjection of zinc finger nucleases (ZFNs), we created a Tp53 knockout rat that contains an 11-bp deletion in exon 3, resulting in a frameshift and premature terminations in the open reading frame. In cohorts of 25 homozygous (Tp53?11/?11), 37 heterozygous (Tp53?11/+) and 30 wild-type rats, the Tp53?11/?11 rats lived an average of 126 days before death or removal from study because of clinical signs of abnormality or formation of tumors. Half of Tp53?11/+ were removed from study by 1 year of age because of tumor formation. Both Tp53?11/+ and Tp53?11/?11 rats developed a wide spectrum of tumors, most commonly sarcomas. Interestingly, there was a strikingly high incidence of brain lesions, especially in Tp53?11/?11 animals. We believe that this mutant rat line will be useful in studying cancer types rarely observed in mice and in carcinogenicity assays for drug development. PMID:22917926

McCoy, Aaron; Besch-Williford, Cynthia L.; Franklin, Craig L.; Weinstein, Edward J.; Cui, Xiaoxia

2013-01-01

205

Moderate Aging Does Not Modulate Morphological Responsiveness of the Neuromuscular System to Chronic Overload in Fischer 344 Rats  

PubMed Central

The purpose of this investigation was to determine the effect of aging on neuromuscular adaptations to chronic overload. Eight young adult (8 mo old) and eight aged (22 mo old) Fischer 344 rats underwent unilateral synergist ablation to overload the plantaris and soleus muscles of that hindlimb and to provide control muscles from the contralateral hindlimb. Cytofluorescent staining and confocal microscopy were used to quantify pre- and post-synaptic features of neuromuscular junctions (NMJs). Histochemical staining and light microscopy were used to assess adaptations of myofibers to chronic overload. Results demonstrate that NMJs of young adult and aged muscles did not undergo morphological remodeling as a result of four weeks of chronic overload. In contrast, myofibers of young and aged rats displayed significant (P <0.05), but similar hypertrophy (~18%) following that four week intervention. In both age groups, however, this hypertrophy was detected in the plantaris, but not the soleus. These data indicate that moderate aging (the equivalent of 65 years in human lifetime) does not modify the sensitivity of the neuromuscular system to chronic overload. PMID:17720323

Deschenes, Michael R.; Tenny, Kelly; Eason, Margaret K.; Gordon, Scott E.

2007-01-01

206

Effect of Probenecid on the Pain-Related Behaviour and Morphological Markers in Orofacial Formalin Test of the Rat.  

PubMed

Probenecid has been widely used in the treatment of gout, but evidence suggest that it may also have anti-nociceptive effects in different inflammatory and pain conditions. We examined the potential modulatory effects of probenecid on behavioural and morphological markers in the orofacial formalin test of the rat. One hour after pre-treatment with vehicle or probenecid (1 mmol/kg body weight) intraperitoneally, 50µl 1.5% formalin solution or physiological saline was injected subcutaneously into the right whisker pad of rats. The rubbing activity directed to the injected whisker pad was then measured for a period of 45 minutes. Four hours after formalin injection, the caudal part of spinal trigeminal nucleus was removed and subjected to c-Fos and neuronal nitric oxide synthase (nNOS) immunohistochemistry and to interleukin-1? and NAD(P)H:quinone oxidoreductase 1 (NQO1) Western blot. There was a significant decrease in formalin-induced biphasic behavioural response and c-Fos and nNOS immunoreactivity in the rats who were pre-treated with probenecid. However there were no alterations in expression of interleukin-1? or NQO1 after formalin administration. Our results suggest that probenecid has an anti-nociceptive effect in the trigeminal inflammatory pain model. This effect may be through influencing the release of prostaglandin E2 or desensitizing the transient receptor potential channel subtype A member 1 or the transient receptor potential channel subtype V member 2 or the effect may be through modulating kynurenic acid levels in the central nervous system. Thus, probenecid might be a potential candidate for the treatment of trigeminal activation related pain conditions. PMID:25106627

Fejes-Szabo, A; Bohar, Z; Nagy-Grocz, G; Vámos, E; Tar, L; P?dör, B; Tajti, J; Toldi, J; Vécsei, L; Párdutz, A

2014-08-01

207

Hippocampal Morphology in a Rat Model of Depression: The Effects of Physical Activity  

PubMed Central

Accumulating in vivo and ex vivo evidences show that humans suffering from depression have decreased hippocampal volume and altered spine density. Moreover, physical activity has an antidepressant effect in humans and in animal models, but to what extent physical activity can affect hippocampal volume and spine numbers in a model for depression is not known. In this study we analyzed whether physical activity affects hippocampal volume and spine density by analyzing a rodent genetic model of depression, Flinders Sensitive Line Rats (FSL), with Magnetic Resonance Imaging (MRI) and ex vivo Golgi staining. We found that physical activity in the form of voluntary wheel running during 5 weeks increased hippocampal volume. Moreover, runners also had larger numbers of thin spines in the dentate gyrus. Our findings support that voluntary wheel running, which is antidepressive in FSL rats, is associated with increased hippocampal volume and spine numbers. PMID:25674191

Sierakowiak, Adam; Mattsson, Anna; Gómez-Galán, Marta; Feminía, Teresa; Graae, Lisette; Aski, Sahar Nikkhou; Damberg, Peter; Lindskog, Mia; Brené, Stefan; Ĺberg, Elin

2015-01-01

208

Whole-Cell Chloride Currents in Rat Astrocytes Accompany Changes in Cell Morphology  

PubMed Central

Astrocytes can change shape dramatically in response to increased physiological and pathological demands, yet the functional consequences of morphological change are unknown. We report the expression of Cl? currents after manipulations that alter astrocyte morphology. Whole-cell Cl? currents were elicited after (1) rounding up cells by brief exposure to trypsin; (2) converting cells from a flat polygonal to a process-bearing (stellate) morphology by exposure to serum-free Ringer’s solution; and (3) swelling cells by exposure to hypo-osmotic solution. Zero-current potentials approximated the Nernst for Cl?, and rectification usually followed that predicted by the constant-field equation. We observed heterogeneity in the activation and inactivation kinetics, as well as in the relative degree of outward versus inward rectification. Cl? conductances were inhibited by 4,4-diisothiocyanostilbene-2,2?-disulfonic acid (200 ?M) and by Zn2+ (1 mM). Whole-cell Cl? currents were not expressed in cells without structural change. We investigated whether changes in cytoskeletal actin accompanying changes in astrocytic morphology play a role in the induction of shape-dependent Cl? currents. Cytochalasins, which disrupt actin polymers by enhancing actin-ATP hydrolysis, elicited whole-cell Cl? conductances in flat, polygonal astrocytes. In stellate cells, elevated intracellular Ca2+ (2 ?M), which can depolymerize actin, enhanced Cl? currents, and high intracellular ATP (5 mM), required for repolymerization, reduced Cl? currents. Modulation of Cl? current by Ca2+ and ATP was blocked by concurrent whole-cell dialysis with phalloidin and DNase, respectively. Phalloidin stabilizes actin polymers and DNase inhibits actin polymerization. Dialysis with phalloidin also prevented hypo-osmotically activated Cl? currents. These results demonstrate how the expression of astrocyte Cl? currents can be dependent on cell morphology, the structure of actin, Ca2+ homeostasis, and metabolism. PMID:8786429

Lascola, Christopher D.; Kraig, Richard P.

2009-01-01

209

Impact of oxidative stress and supplementation with vitamins E and C on testes morphology in rats.  

PubMed

The aim of the study was to verify whether an increased supply of vitamins E and C prevents the detrimental effects of ozone on the testes. The experiment was performed on 5-month-old rats exposed to ozone (0.5 ppm) for 50 days (5 h daily). Simultaneously, the animals were injected with the vitamins in 5-day intervals and at different doses (0.5, 1.5, 4.5, 5 and 15 mg of vitamin E; 0.5, 3, 9, and 50 mg of vitamin C; or both vitamins together, respectively). Gonad sections were PAS stained. In the ozonized males, depletion of germ cells occurred. In the vitamin E groups, the testes were comparable to the controls, excluding the 0.5-mg-dose vitamin E group in which perivascular fibrosis and intertubular hyalinization were observed. In the vitamin C groups, intertubular hyalinization, partial arrested spermatogenesis, and desquamation of the seminiferous epithelium appeared proportional to the vitamin dose. Additionally, premature spermiation was found at a vitamin C dose of 50-mg. In the rats injected with both vitamins, hyalinization and fibrosis appeared in addition to partial arrest of spermatogenesis and vacuolar degeneration. In conclusion, vitamin E protects against the detrimental effects of ozone in rat testes irrespective of the dose applied. This was not observed for vitamin C. Moreover, administration of higher doses of vitamin C intensified the damage to the testes caused by ozone. PMID:16394623

Jedlinska-Krakowska, Maria; Bomba, Grazyna; Jakubowski, Karol; Rotkiewicz, Tadeusz; Jana, Barbara; Penkowski, Aleksander

2006-04-01

210

Normal structure and morphological effects of a corticosteroid on the peripatellar synovial membrane of the rat.  

PubMed

We observed the peripatellar synovial membranes of normal and betamethasone-treated rats with a scanning electron microscope (SEM), light microscope (LM) and transmission electron microscope (TEM). On the basis of SEM findings, the peripatellar synovial membrane is divided into two distinct regions; an upper, smaller, round, non-folded region which is covered with small excrescences, and a lower, larger, horseshoe-shaped region which has numerous folds consisting of cobblestone-like oval cells. These SEM findings were well confirmed by parallel LM and TEM observations of both regions. The synovial membrane of rats treated with intra-articular injections of betamethasone, an anti-inflammatory agent for rheumatoid arthritis, showed cell-sized excrescences on the surface of the non-folded regions. Under LM and TEM, the synovial membrane of treated rats showed an expansion of the intercellular spaces with collagen fibers, swelling of vacuoles in the cytoplasm in the type M synoviocytes, and increases in the number and elongation of microvilli of the type M synoviocytes. These observations suggest that repeated betamethasone injection therapy may result in unnecessary damage to the synovial membrane. PMID:10361404

Murashige, N; Gotoh, T; Ichikawa, Y; Yamashita, K

1999-04-01

211

Effect of curcumin on rat sperm morphology after the freeze-thawing process  

PubMed Central

Reactive oxygen species (ROS) generation, induced by the cryopreservation process, can be responsible for mammalian sperm damage. Curcumin is known as an effective antioxidant against oxidative stress. The aim of this study was to evaluate the effects of curcumin on sperm count, motility and viability, semen total antioxidant capacity and DNA integrity of rat spermatozoa during semen freeze-thawing process. Sperm collected from 10 adult rats were divided into two groups (n=10 for each group): control and a test group supplemented with 2.5 mM curcumin. After freezing-thawing, the number of spermatozoa, motility, viability, total antioxidant capacity (TAC), and DNA integrity of the sperm were analyzed. Motility, viability and DNA integrity of sperm were significantly preserved in treatment groups compared to the control (p < 0.05) after freezing-thawing. Following cryopreservation, TAC was significantly preserved in thawing semen supplemented with curcumin compared to the control group (p<0.05). Based on our results, it is concluded that curcumin addition during freezing resulted in positive effects on sperm parameters after thawing in adult rats.

Soleimanzadeh, Ali; Saberivand, Adel

2013-01-01

212

Levonorgestrel decreased cilia beat frequency of human fallopian tubes and rat oviducts without changing the morphological structure.  

PubMed

Levonorgestrel, a derivative of progesterone, effectively protects women from unwanted pregnancy as an emergency contraceptive. Previous studies have not successfully determined the mechanism by which levonorgestrel acts. Here we analyzed cilia beat action and cilia morphology under levonorgestrel exposure in vitro and in vivo using both light and electron microscopy. There was a significant decrease in the ciliary beat frequency (CBF) of human fallopian tubes between the mucosal explants bathed in 5 ?M levonorgestrel compared with those bathed in medium alone (P < 0.05). The CBF tended to decrease more in the ampulla relative to the isthmus but did not differ between the proliferative phase and secretory phase. In rat oviducts, levonorgestrel resulted in a similar reduction in the CBF (~10%) compared with the saline control group (P < 0.05). Histological and ultrastructural analysis demonstrated no changes in the percentage of ciliated cells or to the classic "9 + 2" structure of cilia by levonorgestrel treatment in either system. Thus levonorgestrel reduced the CBF without damaging cilia morphology. Decreases in the CBF may indicate a pathological role for levonorgestrel in the transportation of the ovum and zygote in the fallopian tube. This article is protected by copyright. All rights reserved. PMID:25399777

Zhao, Weihong; Zhu, Qian; Yan, Mingxing; Li, Cheng; Yuan, Jiangjing; Qin, Guojuan; Zhang, Jian

2014-11-15

213

Morphological characteristics and identification of islet-like cells derived from rat adipose-derived stem cells cocultured with pancreas adult stem cells.  

PubMed

Diabetes is a significant public health problem that can be treated with insulin therapy; however, therapies designed to cure diabetes are limited. The goal of the current study was to assess the potential for curative treatment of diabetes using adipose-derived stem cells (ADSCs). To achieve this goal, the differentiation of rat ADSCs into pancreatic islet-like cells induced by coculture with pancreatic adult stem cells (PASCs) was characterized. Differentiation of ADSCs into islet-like cells induced by coculturing was determined morphologically, as well as by the assessment of islet cell markers using dithizone staining, immunohistochemistry, RT-PCR, qPCR, and western blotting. The results showed that ADSCs formed islet-like round cell masses after coculture with PASCs. These differentiated cells were shown to be positive for islet cell markers, including dithizone incorporation; PDX1, CK19 and Nestin by immunohistochemistry, and insulin, PDX1 and glucagon expression by RT-PCR. Differentiated ADSCs induced by coculturing also expressed insulin at the mRNA and protein level, with the level of insulin mRNA expression in cocultured ADSCs being 0.05 times greater than that of PASCs (P?

Hefei, Wang; Yu, Ren; Haiqing, Wu; Xiao, Wang; Jingyuan, Wang; Dongjun, Liu

2015-03-01

214

Genetic, morphological, and ecological characterization of a hybrid zone that spans a migratory divide.  

PubMed

This study characterizes a hybrid zone that spans a migratory divide between subspecies of the Swainson's thrush (Catharus ustulatus), a long distance migratory songbird, in the Coast Mountains of British Columbia. To assess the potential for a barrier to gene flow between the subspecies, I: (1) analyzed the shape and width of genetic and morphological clines relative to estimates of dispersal distance, (2) assessed the ratio of parental to hybrid genotypes across the hybrid zone, (3) estimated population density across the hybrid zone, and (4) compared the spatial relationship between the hybrid zone and an existing environmental gradient. The results indicate that the hybrid zone is characterized by mostly concordant character clines that are narrow relative to dispersal, the absence of a hybrid swarm, and low population density at the center of the zone. This hybrid zone and additional regions of contact between these subspecies are found on the border between coastal and interior climatic regions throughout the Pacific Northwest. An identified shift in the location, but not the width, of the mtDNA cline relative to the nuclear clines is consistent with asymmetrical hybridization. Neutral diffusion of populations following secondary contact and hybrid superiority within an ecotone are insufficient explanations for the observed patterns. The hypothesis that best fits the data is that the Swainson's thrush hybrid zone is a tension zone maintained by dispersal and ecologically mediated barriers to gene flow. PMID:18039327

Ruegg, Kristen

2008-02-01

215

Cloning and pharmacological characterization of a rat kappa opioid receptor.  

PubMed Central

A full-length cDNA was isolated from a rat striatal library by using low-stringency screening with two PCR fragments, one spanning transmembrane domains 3-6 of the mouse delta opioid receptor and the other unidentified but homologous to the mouse delta receptor from rat brain. The novel cDNA had a long open reading frame encoding a protein of 380 residues with 59% identity to the mouse delta receptor and topography consistent with a seven-helix guanine nucleotide-binding protein-coupled receptor. COS-1 cells transfected with the coding region of this clone showed high-affinity binding to kappa opioid receptor-selective ligands such as dynorphin A and U-50,488 and also nonselective opioid ligands such as bremazocine, ethylketocyclazocine, and naloxone. Not bound at all (or bound with low affinity) were dynorphin A-(2-13), enantiomers of naloxone and levophanol [i.e., (+)-naloxone and dextrorphan], and selective mu and delta opioid receptor ligands. Activation of the expressed receptor by kappa receptor agonists led to inhibition of cAMP. Finally, in situ hybridization revealed a mRNA distribution in rat brain that corresponded well to the distribution of binding sites labeled with kappa-selective ligands. These observations indicate that we have cloned a cDNA encoding a rat kappa receptor of the kappa 1 subtype. Images Fig. 3 PMID:8234341

Meng, F; Xie, G X; Thompson, R C; Mansour, A; Goldstein, A; Watson, S J; Akil, H

1993-01-01

216

Characterization of a rat osteotomy model with impaired healing  

Microsoft Academic Search

BACKGROUND: Delayed union or nonunion are frequent and feared complications in fracture treatment. Animal models of impaired bone healing are rare. Moreover, specific descriptions are limited although understanding of the biological course of pathogenesis of fracture nonunion is essential for therapeutic approaches. METHODS: A rat tibial osteotomy model with subsequent intramedullary stabilization was performed. The healing progress of the osteotomy

Christine Kratzel; Camilla Bergmann; Georg Duda; Stefan Greiner; Gerhard Schmidmaier; Britt Wildemann

2008-01-01

217

Characterization of tumor cell lines from a spontaneous rat sarcoma expressing an endogenous retrovirus.  

PubMed

We have characterized various biologic, immunologic and growth properties of several cell lines established from a spontaneous rat sarcoma that was discovered more than 60 yr ago. The tumors consisted of mixed cell types with no detectable host cellular immune response. Cultures derived from single-cell clones of the parental cell line were non-invasive but highly tumorigenic even in adult rats. The cultured cells spontaneously released replication-competent endogenous rat type C virus which did not carry a transforming gene in its genome. Since normal cells from the same rat strain did not produce a retrovirus, it is possible that production of the endogenous retrovirus may have triggered specific cellular changes necessary for the oncogene expression and development of this tumor. PMID:2982624

Varnier, O E; Raffanti, S P; Muratore, O; Repetto, C M; Pippia, P; Tilloca, G; Meloni, M A; Ivaldi, G; Rasheed, S

1985-01-01

218

Characterization of a panel of rat ventral prostate epithelial cell lines immortalized in the presence or absence of androgens.  

PubMed

We have transfected rat ventral prostate (RVP) epithelial cells with a plasmid containing the SV40 large T-antigen in an attempt to establish a panel of cell lines that will be useful in molecular genetic studies of prostate cell function. Since the distribution of cell types in the RVP is dramatically affected by androgen withdrawal and replacement, cells isolated from normal, castrated, or castrated rats that were given daily injections of testosterone were used in these experiments. Cell lines were established in media that were supplemented or depleted of androgens to accommodate the possible requirements of different prostate cell types. Numerous cell lines were isolated which retain characteristics of RVP epithelial cells and five of these cell lines were studied in detail. All five cell lines express the SV40 large T-antigen, supporting the role of this viral protein in immortalization. The RVP cell lines were shown to contain high levels of functional glucocorticoid receptors, but very low levels of androgen binding activity even though androgen receptor RNA could be detected. It was determined that the decreased androgen receptor activity in the RVP cells was apparently due to low receptor expression based on the results of transient transfection assays using androgen receptor cDNA. Taken together, the biochemical, cytological, and morphological characterizations of the RVP cell lines suggest that they may all have been derived from basal prostate epithelial cells despite the initial differences in androgen status of the animal and the level of androgens in the culture media. PMID:1330656

Rundlett, S E; Gordon, D A; Miesfeld, R L

1992-11-01

219

Characterization of the Pre-meiotic S Phase through Incorporation of BrdU during Spermatogenesis in the Rat  

PubMed Central

Seminiferous tubules in mammals have histological arrangements defined by the associations between somatic cells and germ cells. The processes of DNA synthesis in meiotic and mitotic cells have different features that are not easily distinguishable through morphological means. In order to characterize the pre-meiotic S phase, 5-bromo-2’-deoxyuridine (BrdU) was injected intraperitoneally into Wistar rats, which were sacrificed 30 min, 2 hr, and 24 hr after injection. We found three different labeling patterns. One of these patterns was characterized by a distribution of the label in the form of speckles, most of which were associated with the nuclear envelope (labeling type I). We suggest that this pattern is due to mitotic DNA synthesis of type B spermatogonia. Labeling type II consisted of labeled foci scattered throughout the nuclear volume, which can be correlated with preleptotenic cells in pre-meiotic DNA synthesis. After 24 hr of incorporation, a third type of labeling, characterized by large speckles, was found to be related to cells in the “bouquet” stage; that is, cells in transition between the leptotene and zygotene phases. Our results indicate that BrdU incorporation induces different labeling patterns in the mitotic and pre-meiotic S phases and thus makes it possible to identify somatic and germinal cells. PMID:23776014

Muńoz-Velasco, Israel; Ortíz, Rosario; Echeverría, Olga M.; Escobar, María L.

2013-01-01

220

Hippocampal morphology and spatially related behavior in Long-Evans and CFY rats.  

PubMed

Behavioral responses to novelty in an open field and spatial learning in a radial maze with four arms out of eight reinforced were tested in male and female CFY and Long-Evans rats. Subsequently, the sizes of the total hippocampi and of various hippocampal cell layers and terminal fields at the midseptotemporal level were measured in Timm-stained sections. No strain differences were found in the open field (except for defecation). In the radial maze, Long-Evans rats showed better spatial reference memory capabilities than rats of the CFY strain. The relative sizes of the intra- and infrapyramidal mossy fiber (IIP-MF) projections did not differ between the strains. Within the more variable CFY strain, a positive correlation between the size of the IIP-MF projection and radial maze performance was found. The absolute sizes of the entire hippocampi and all hippocampal layers at the midseptotemporal level were larger in the CFY strain. The size of the suprapyramidal mossy fiber projection was related to the number of granule cells and to the ratio between granule and CA3 pyramidal cells. In contrast, the size of the IIP-MF projection did not correlate with either of these variables. The results indicate that the size of the mossy fiber projection may be determined mainly by the available postsynaptic surface on the dendrites of CA3 pyramidal neurons. Furthermore, an increased number of granule cells and their larger projection to the apical dendrites of pyramidal neurons does not appear to result in physiological changes with behavioral consequences.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8364679

Schwegler, H; Mueller, G G; Crusio, W E; Szemes, L; Seress, L

1993-01-01

221

Chemical and morphological characterization of soot and soot precursors generated in an inverse diffusion flame with aromatic and aliphatic fuels  

Microsoft Academic Search

Knowledge of the chemical and physical structure of young soot and its precursors is very useful in understanding the paths leading to soot particle inception. This paper presents chemical and morphological characterization of the products generated in ethylene and benzene inverse diffusion flames (IDF) using different analytical techniques. The trend in the data indicates that the soot precursor material and

Alexander Santamaria; Nancy Yang; Eric Eddings; Fanor Mondragon

2010-01-01

222

Genetic, morphological and spatial characterization of two populations of Mabea fistulifera Mart. (Euphorbiaceae), in different successional stages  

Microsoft Academic Search

Two popu lations of Mabea fistulifera (Euphorbiaceae) located a t Rio Doce State Park (Minas Gerais, Brazil) in places characterized as in d ifferent successional stages, were investigated through genetic and ecological traits. Twenty randomly chosen individuals from each population had its genetic data assessed by 43 RAPD markers and were also evaluated through five morphologic traits and its spatial

Maíra Figueiredo Goulart; Sérvio Pontes Ribeiro; Maria Bernadete Lovato

2005-01-01

223

Morphological Features of Adult Rats of IS/Kyo and IS-Tlk/Kyo Strains with Lumbar and Caudal Vertebral Anomalies  

PubMed Central

IS-Tlk/Kyo, a mutant derived from IS/Kyo strain, exhibits a kinked and/or short tail, in addition to the congenital lumbar vertebral anomaly. Homozygotes of Tlk dominant gene are known to die during embryonic development. We previously reported the morphological features of the skeleton in IS/Kyo and IS-Tlk/Kyo fetuses and of the heart in IS/Kyo fetuses [19]. This study was conducted to clarify the morphological features of the skeleton in both adult rats and of the heart in adult IS/Kyo rats. Ventricular septal defect (VSD) was observed in 3 out of 10 IS/Kyo rats. Neither splitting of lumbar vertebra and supernumerary rib (in both strains) nor fused or absent caudal cartilage (in IS-Tlk/Kyo strain) was detected in adult rats. Fusion of lumbar vertebrae was observed in almost all specimens together with lumbarization of sacral vertebrae in a few specimens in both adult rats as well as fusion of sacral and caudal vertebrae only in adult IS-Tlk/Kyo rats. In addition, a severe reduction in the ossified sacral and caudal vertebrae was noted in adult IS-Tlk/Kyo rats (mean number: 20.6) and IS/Kyo rats (31.8), and the difference was similar to that in the length of sacral and caudal vertebrae. These results suggest that the Tlk gene may be involved in both the congenital and acquired abnormal formation of the lower vertebral centra as well as the persistent occurrence of VSD by the background gene in IS/Kyo strain. PMID:25077756

Takano, Masao; Ogawa, Emi; Saitou, Tsubasa; Yamaguchi, Yuko; Asano, Yuzo; Serikawa, Tadao; Kuramoto, Takashi

2014-01-01

224

Bioethanol-gasoline fuel blends: exhaust emissions and morphological characterization of particulate from a moped engine.  

PubMed

This study was aimed at evaluating the effects of gasoline-ethanol blends on the exhaust emissions in a catalyst-equipped four-stroke moped engine. The ethanol was blended with unleaded gasoline in at percentages (10, 15, and 20% v/v). The regulated pollutants and the particulate matter emissions were evaluated over the European ECE R47 driving cycle on the chassis dynamometer bench. Particulate matter was characterized in terms of total mass collected on filters and total number ofparticles in the range 7 nm-10 microm measured by electrical low-pressure impactor (ELPI). In addition, particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions were evaluated to assess the health impact of the emitted particulate. Finally, an accurate morphological analysis was performed on the particulate by high-resolution transmission electron microscope (TEM) equipped with a digital image-processing/data-acquisition system. In general, CO emission reductions of 60-70% were obtained with 15 and 20% v/v ethanol blends, while the ethanol use did not reduce hydrocarbon (HC) and NOx emissions. No evident effect of ethanol on the particulate mass emissions and associated PAHs emissions was observed. Twenty-one PAHs were quantified in the particulate phase with emissions ranging from 26 to 35 microg/km and benzo[a]pyrene equivalent (BaPeq) emission factors from 2.2 to 4.1 microg/km. Both particulate matter and associated PAHs with higher carcinogenic risk were mainly emitted in the submicrometer size range (<0.1 microm). On the basis of the TEM observations, no relevant effect of the ethanol use on the particulate morphology was evidenced, showing aggregates composed ofprimary particles with mean diameters in the range 17.5-32.5 nm. PMID:22916436

Seggiani, Maurizia; Prati, M Vittoria; Costagliola, M Antonietta; Puccini, Monica; Vitolo, Sandra

2012-08-01

225

Functional and morphologic changes associated with insulinoma transplantation into diabetic rats.  

PubMed

Because of the technical difficulties encountered with human islet cell transplantation, alternatives toward supplying the juvenile diabetic with an endogenous insulin source are sought. With the use of a streptozotocin-induced diabetic rat model, it was found that by transplantation of a benign insulinoma, the glomerular deposition of material stained by the periodic acid-Schiff method, IgG, IgM, and C3 may be prevented. This effect was found only when transplantation of the insulin-producing tumor occurred within 2-4 weeks of the induction of diabetes. The data suggest that successful insulinoma engraftment can prevent the glomerular mesangial lesions from developing. PMID:6305199

Reintgen, D S; Croker, B; Verveart, C; Seigler, H F

1983-07-01

226

Production and characterization of spontaneous rat heart endothelial cell lines.  

PubMed

Endothelial cells (EC) are important regulatory cells in physiology and pathology. in vitro studies with rat EC from heart tissue are hampered by laborious isolation and purification procedures, low yield, and limited lifespan of the cells. Therefore, it is essential to obtain long-term heart EC lines that offer a more adequate in vitro system for studying rat heart EC. An ex vivo perfusion model was used to isolate EC from rat heart. Isolation and culture conditions were modified to allow spontaneous development of immortalized rat heart EC (RHEC) lines. Produced cell lines were tested for endothelial nature using a panel of markers. The selected RHEC lines were subsequently tested for a series of phenotypic and functional properties representative of EC in the context of physiologic and inflammatory functions in vivo. A series of three spontaneous RHEC lines was produced from 13 isolations from Lewis rat hearts: RHEC-3, RHEC-10, and RHEC-11. These lines were stable for more than 30 passages (RHEC-3 for more than 100). The cell lines were tumorigenic and developed hemangiomas on in vivo injection. All three lines expressed major histocompatibility complex (MHC) class I but no MHC class II. Intercellular adhesion molecule 1 was only expressed by RHEC-3. Cytokine stimulation induced vascular cell adhesion molecule 1 in RHEC-3 and RHEC-11 as well as MHC class II in all three lines in different quantities. The phenotypic characteristics of the different RHEC lines resembled the myocardial microvascular endothelium in situ. The three lines expressed angiotensin-converting enzyme, and they responded to histamine and ATP but not to thrombin and bradykinin. They constitutively produced small amounts of endothelin and high levels of tissue plasminogen activator; they produced little (after stimulation with phorbol-ester PMA) or no von Willebrand factor. The RHEC lines produced thromboxane A2 but no prostacyclin; on stimulation with arachidonic acid and A23187, they produced prostaglandin E2. Therefore, we conclude the following. 1) The described isolation and culture technique is successful for production of spontaneous stable EC lines from rat heart. 2) RHEC-3, -10, and -11 can be considered a series of different lines representative of the heterogeneity of heart microvascular endothelium in vivo. 3) The RHEC lines offer a series of valuable tools to study various heart EC functions and mechanisms in physiology and pathology. PMID:8780162

Derhaag, J G; Duijvestijn, A M; Emeis, J J; Engels, W; van Breda Vriesman, P J

1996-02-01

227

Effects of leptin on sperm count and morphology in Sprague-Dawley rats and their reversibility following a 6-week recovery period.  

PubMed

Altered epididymal sperm count and morphology following leptin treatment has been reported recently. This study examined the effects of 42 days of leptin treatment on sperm count and morphology and their reversibility during a subsequent 56-day recovery period. Twelve-week-old male Sprague-Dawley rats were randomised into four leptin and four saline-treated control groups (n = 6). Intraperitoneal injections of leptin were given daily (60 ?g Kg(-1) body weight) for 42 days. Controls received 0.1 ml of 0.9% saline. Leptin-treated animals and their respective age-matched controls were euthanised on either day 1, 21, 42 or 56 of recovery for collection of epididymal spermatozoa. Sperm concentration was determined using a Makler counting chamber. Spermatozoa were analysed for 8-hydroxy-2-deoxyguanosine and DNA fragmentation (Comet assay). Data were analysed using anova. Sperm concentration was significantly lower but fraction of abnormal spermatozoa, and levels of 8-hydroxy-2-deoxyguanosine were significantly higher in leptin-treated rats on day 1 of recovery. Comet assays revealed significant DNA fragmentation in leptin-treated rats. These differences were reduced by day 56 of recovery. It appears that 42 days of leptin treatment to Sprague-Dawley rats has significant adverse effects on sperm count and morphology that reverse following discontinuation of leptin treatment. PMID:25269426

Almabhouh, F A; Osman, K; Siti Fatimah, I; Sergey, G; Gnanou, J; Singh, H J

2014-10-01

228

Morphological characterization of lineages within the calcified tropical seaweed genus Halimeda (Bryopsidales, Chlorophyta)  

Microsoft Academic Search

Halimeda Lamouroux constitutes a genus of calcified and segmented green seaweeds within the Bryopsidales. Molecular phylogenetic assessments have uncovered five principal monophyletic lineages within the genus. In the present study we define these lineages morphologically. We gathered morphological data from specimens used in the molecular analyses as well as from collections having a similar morphology and originating from the same

Heroen Verbruggen; Wiebe HCF Kooistra

2004-01-01

229

Comparison of functional and morphological deficits in the rat after gestational exposure to ionizing radiation  

SciTech Connect

Ionizing radiation is a precise tool for altering formation of the developing cerebral cortex of the fetal rat. Whole body exposure of the pregnant rat on gestational day 13, 15 or 17 to 1.0 Gy of gamma radiation resulted in maximum thinning of the cortex on days 15 and 17. In the preweaning period, functional tests (negative geotaxis, reflex suspension, continuous corridor and gait) were most affected by irradiation gestational day 15, as was body weight. When a lower dose of radiation (0.75 Gy) was used on gestational day 15, the damage to the cortex was much less but behavioral changes were still present. Frontal, parietal and occipital areas of the cortex were approximately equally affected. Using stepwise multiple regression analysis, the linkage of functional tests and cortical thickness was examined. Functional variables which were most commonly included as predictors of frontal and parietal cortex were negative geotaxis and continuous corridor. Occipital cortical layers were not predicted by behavioral variables. In predicting function using cortical variables, frontal cortex was better than parietal and occipital cortex was the poorest predictor.

Norton, S.; Kimler, B.F.

1988-07-01

230

Characterization of Prohibitin in a Newly Established Rat Ovarian Granulosa Cell Line  

E-print Network

of these steroidogenic proteins. At 39 C, RGA-1 cells also dis- played increases in p53 protein levels, indicative affect regulation of the cell cycle. The ability of a cell to regulate this process of devel- opmentCharacterization of Prohibitin in a Newly Established Rat Ovarian Granulosa Cell Line WINSTON E

Mayo, Kelly E.

231

CLONING, EXPRESSION, AND CHARACTERIZATION OF RAT S-ADENOSYL-L-METHIONINE: ARSENIC (III) METHYLTRANSFERASE (CYT19)  

EPA Science Inventory

CLONING, EXPRESSION, AND CHARACTERIZATION OF RAT S-ADENOSYL-L-METHIONINE: ARSENIC(III) METHYLTRANSFERASE (cyt19) Stephen B. Waters1 , Felicia Walton1 , Miroslav Styblo1 , Karen Herbin-Davis2, and David J. Thomas2 1 School of Medicine, University of North Carolina at Chape...

232

Characterization of vasopressin receptors in cultured cells derived from the region of rat brain circumventricular organs  

Microsoft Academic Search

The aim of the present study was to characterize vasopressin receptors within the two circumventricular organs located in the lamina terminalis of the rat brain, namely the organum vasculosum of the lamina terminalis and the subfornical organ. Cells derived from both structures were isolated, cultured and intracellular Ca2+ concentrations were measured in single fura-2 loaded neurons and astrocytes after application

M. Jurzak; A. R. Müller; R. Gerstberger

1995-01-01

233

Simultaneous Characterization of Metabolic, Cardiac, Vascular and Renal Phenotypes of Lean and Obese SHHF Rats  

PubMed Central

Individuals with metabolic syndrome (MetS) are prone to develop heart failure (HF). However, the deleterious effects of MetS on the continuum of events leading to cardiac remodeling and subsequently to HF are not fully understood. This study characterized simultaneously MetS and cardiac, vascular and renal phenotypes in aging Spontaneously Hypertensive Heart Failure lean (SHHF+/? regrouping +/+ and +/cp rats) and obese (SHHFcp/cp, “cp” defective mutant allele of the leptin receptor gene) rats. We aimed to refine the milestones and their onset during the progression from MetS to HF in this experimental model. We found that SHHFcp/cp but not SHHF+/? rats developed dyslipidemia, as early as 1.5 months of age. This early alteration in the lipidic profile was detectable concomitantly to impaired renal function (polyuria, proteinuria but no glycosuria) and reduced carotid distensibility as compared to SHHF+/? rats. By 3 months of age SHHFcp/cp animals developed severe obesity associated with dislipidemia and hypertension defining the onset of MetS. From 6 months of age, SHHF+/? rats developed concentric left ventricular hypertrophy (LVH) while SHHFcp/cp rats developed eccentric LVH apparent from progressive dilation of the LV dimensions. By 14 months of age only SHHFcp/cp rats showed significantly higher central systolic blood pressure and a reduced ejection fraction resulting in systolic dysfunction as compared to SHHF+/?. In summary, the metabolic and hemodynamic mechanisms participating in the faster decline of cardiac functions in SHHFcp/cp rats are established long before their physiological consequences are detectable. Our results suggest that the molecular mechanisms triggered within the first three months after birth of SHHFcp/cp rats should be targeted preferentially by therapeutic interventions in order to mitigate the later HF development. PMID:24831821

Youcef, Gina; Olivier, Arnaud; L'Huillier, Clément P. J.; Labat, Carlos; Fay, Renaud; Tabcheh, Lina; Toupance, Simon; Rodriguez-Guéant, Rosa-Maria; Bergerot, Damien; Jaisser, Frédéric; Lacolley, Patrick; Zannad, Faiez; Laurent Vallar; Pizard, Anne

2014-01-01

234

The morphology of Golgi-stained neurons in lamina II of the rat spinal cord.  

PubMed Central

Golgi-stained neurons in Lamina II of the rat spinal cord were examined by light microscopy. Stalked and islet cells similar to those seen in other species were found. Stalked cells were present in large numbers in the dorsal part of the lamina where they made up nearly half the population of stained cells. Islet cells were found throughout the lamina and constituted about one third of the total population. In the ventral part of the lamina half of the stained cells did not fall into either category, but could be divided into groups on the basis of dendritic spread. The axons of many of these cells either remained in Lamina II or passed ventrally into Lamina III. Some of these cells may correspond to the stellate or the II-III border cells which have been seen in human spinal cord and cat medulla respectively. PMID:2447052

Todd, A J; Lewis, S G

1986-01-01

235

Morphology of rostral medullary neurons with intrinsic pacemaker activity in the rat.  

PubMed

Neurons with regular ongoing activity attributable to intrinsic pacemaker properties were recorded in coronal tissue slices within the nucleus reticularis rostroventrolateralis of the rat medulla oblongata (RVL). The cells were injected with horseradish peroxidase or Lucifer yellow and their dendritic and proximal axonal characteristics were investigated (n = 15). These small-to-medium-sized neurons had a simple dendritic arborization (3-6 primary dendrites branching up to 3 times) apparently confined within the limits of nucleus RVL and with limited extension in the rostrocaudal direction. Their axons originated either from the cell body or from a primary dendrite and coursed in a dorsomedial direction without giving rise to local arborizations. It is concluded that RVL pacemaker neurons, presumed to represent a non-adrenergic class of sympathoexcitatory premotor neurons, exhibit characteristics reminiscent of the archetypal 'reticular core' neurons. PMID:1718558

Sun, M K; Stornetta, R L; Guyenet, P G

1991-08-01

236

Characterization of peptide inducing cataractogenesis in lens of hereditary cataractous rat (ICR/f RAT).  

PubMed

A material with inhibitory action to Na+/K+ ATPase was found in the lens of the ICR/f rat, a recessive hereditary cataractous rat. The material also induced lens opacification in vitro. From the results of amino acid analysis and by secondary ion mass spectroscopy, it was suggested that the material might contain approximately equimolar amounts of four amino acids, ie, aspartic acid, serine, glutamic acid and glycine, and that the molecular weight was 444. These facts suggested that this material with Na+/K+ ATPase inhibitory action might be a peptide. However, there is not yet any corroborating evidence to show whether this peptide is only a single material or not. The peptide significantly increased with aging in the lens of the ICR/f rat until approximately 90 days, when cataract became manifest, but its content decreased thereafter. This study suggests that one of the causes of cataractogenesis in the ICR/f rat might be this peptide, which is transformed in the lens with aging, and also that the peptide might accelerate lens opacification after cataractogenesis. PMID:2552201

Kamei, A; Sakai, H

1989-01-01

237

Cardiac oxidative stress determination and myocardial morphology after a single ecstasy (MDMA) administration in a rat model.  

PubMed

Experimental and clinical data indicate that 3,4-methylenedioxy-N-methylamphetamine (MDMA) abuse can produce significant cardiovascular toxicity. A mechanism may be a direct toxic effect of redox active metabolites of MDMA. To evaluate the effect of a single MDMA dose on cellular antioxidant defence system and to investigate the morphology in male albino rats, total glutathione (GSH), oxidised glutathione (GSSG), ascorbic acid (AA), glutathione peroxidase (GPx), glutathione reductase (GR), superoxide dismutase (SOD) and malondialdehyde (MDAL) were studied. The effects were evaluated at 3, 6, 16 and 24 h after MDMA administration. Antioxidant enzymes activity was significantly reduced: GPx (-24%) and SOD (-50%) after 3 h and GR (-19%) after 6 h from treatment. AA levels decrease (-37%) after 3 h and (-30%) after 6 h; MDAL level increased (+119%) after 3 h; GSH levels decreased after 3 (31.3%) and 6 h (37.9%) from MDMA treatment. GSSG content was not affected by ecstasy administration. Myocardial contraction band necrosis (CBN) was already visible in rats killed at 6 h. After 16 h, macrophagic monocytes around the necrotic myocardial cells were observed, and within 24 h, this infiltrate became more widespread with an early removal of the necrotic material. Calcium deposits were observed within ventricular cardiomyocytes with intact nuclei and sarcomeres. Single administration of MDMA can significantly alter the cellular antioxidant defence system and produce oxidative stress which may result in lipid peroxidation and disruption of Ca(2 +) homeostasis. The depression in Ca(2+) regulatory mechanism by reactive oxygen species ultimately results in intracellular Ca(2 +) overload, CBN and cell death. PMID:18594849

Cerretani, Daniela; Riezzo, Irene; Fiaschi, Anna Ida; Centini, Fabio; Giorgi, Giorgio; D'Errico, Stefano; Fiore, Carmela; Karch, Steven B; Neri, Margherita; Pomara, Cristoforo; Turillazzi, Emanuela; Fineschi, Vittorio

2008-11-01

238

Surfactant secretion in LRRK2 knock-out rats: changes in lamellar body morphology and rate of exocytosis.  

PubMed

Leucine-rich repeat kinase 2 (LRRK2) is known to play a role in the pathogenesis of various diseases including Parkinson disease, morbus Crohn, leprosy and cancer. LRRK2 is suggested to be involved in a number of cell biological processes such as vesicular trafficking, transcription, autophagy and lysosomal pathways. Recent histological studies of lungs of LRRK2 knock-out (LRRK2 -/-) mice revealed significantly enlarged lamellar bodies (LBs) in alveolar type II (ATII) epithelial cells. LBs are large, lysosome-related storage organelles for pulmonary surfactant, which is released into the alveolar lumen upon LB exocytosis. In this study we used high-resolution, subcellular live-cell imaging assays to investigate whether similar morphological changes can be observed in primary ATII cells from LRRK2 -/- rats and whether such changes result in altered LB exocytosis. Similarly to the report in mice, ATII cells from LRRK2 -/- rats contained significantly enlarged LBs resulting in a >50% increase in LB volume. Stimulation of ATII cells with ATP elicited LB exocytosis in a significantly increased proportion of cells from LRRK2 -/- animals. LRRK2 -/- cells also displayed increased intracellular Ca(2+) release upon ATP treatment and significant triggering of LB exocytosis. These findings are in line with the strong Ca(2+)-dependence of LB fusion activity and suggest that LRRK2 -/- affects exocytic response in ATII cells via modulating intracellular Ca(2+) signaling. Post-fusion regulation of surfactant secretion was unaltered. Actin coating of fused vesicles and subsequent vesicle compression to promote surfactant expulsion were comparable in cells from LRRK2 -/- and wt animals. Surprisingly, surfactant (phospholipid) release from LRRK2 -/- cells was reduced following stimulation of LB exocytosis possibly due to impaired LB maturation and surfactant loading of LBs. In summary our results suggest that LRRK2 -/- affects LB size, modulates intracellular Ca(2+) signaling and promotes LB exocytosis upon stimulation of ATII cells with ATP. PMID:24465451

Miklavc, Pika; Ehinger, Konstantin; Thompson, Kristin E; Hobi, Nina; Shimshek, Derya R; Frick, Manfred

2014-01-01

239

Surfactant Secretion in LRRK2 Knock-Out Rats: Changes in Lamellar Body Morphology and Rate of Exocytosis  

PubMed Central

Leucine-rich repeat kinase 2 (LRRK2) is known to play a role in the pathogenesis of various diseases including Parkinson disease, morbus Crohn, leprosy and cancer. LRRK2 is suggested to be involved in a number of cell biological processes such as vesicular trafficking, transcription, autophagy and lysosomal pathways. Recent histological studies of lungs of LRRK2 knock-out (LRRK2 -/-) mice revealed significantly enlarged lamellar bodies (LBs) in alveolar type II (ATII) epithelial cells. LBs are large, lysosome-related storage organelles for pulmonary surfactant, which is released into the alveolar lumen upon LB exocytosis. In this study we used high-resolution, subcellular live-cell imaging assays to investigate whether similar morphological changes can be observed in primary ATII cells from LRRK2 -/- rats and whether such changes result in altered LB exocytosis. Similarly to the report in mice, ATII cells from LRRK2 -/- rats contained significantly enlarged LBs resulting in a >50% increase in LB volume. Stimulation of ATII cells with ATP elicited LB exocytosis in a significantly increased proportion of cells from LRRK2 -/- animals. LRRK2 -/- cells also displayed increased intracellular Ca2+ release upon ATP treatment and significant triggering of LB exocytosis. These findings are in line with the strong Ca2+-dependence of LB fusion activity and suggest that LRRK2 -/- affects exocytic response in ATII cells via modulating intracellular Ca2+ signaling. Post-fusion regulation of surfactant secretion was unaltered. Actin coating of fused vesicles and subsequent vesicle compression to promote surfactant expulsion were comparable in cells from LRRK2 -/- and wt animals. Surprisingly, surfactant (phospholipid) release from LRRK2 -/- cells was reduced following stimulation of LB exocytosis possibly due to impaired LB maturation and surfactant loading of LBs. In summary our results suggest that LRRK2 -/- affects LB size, modulates intracellular Ca2+ signaling and promotes LB exocytosis upon stimulation of ATII cells with ATP. PMID:24465451

Thompson, Kristin E.; Hobi, Nina; Shimshek, Derya R.; Frick, Manfred

2014-01-01

240

Solid state microcellular foamed poly(lactic acid): morphology and property characterization.  

PubMed

Poly(lactic acid) or PLA is a plant-based biodegrable plastic which exhibits many properties that are equivalent to or better than many petroleum-based plastics. However, there have been few commercial applications due to its lower impact resistance and higher cost than synthetic plastics. In this paper, the concept of creating microcellular foamed structures in PLA as a means to improve its shortcomings is presented. The effect of the foaming conditions (temperature and time) on the void fraction, volume expansion ratio, impact strength and tensile properties of foamed PLA is discussed. Each step of microcellular processing is addressed including: the manufacture of PLA film; the saturation of the samples with gas; the microcellular foaming of PLA; the void fraction determination, volume expansion ratio calculation, impact and tensile property characterization of foamed samples. The microcellular morphologies developed in PLA samples were a strong function of the foaming conditions. Due to the presence of foamed microcells, a twofold expansion ratio and significant improvements in the impact resistance (twofold increase over unfoamed PLA), strain at break (up to twofold increase over unfoamed PLA) and toughness (up to fourfold increase over unfoamed PLA) were achieved in PLA. PMID:17855079

Matuana, L M

2008-06-01

241

Structural and morphological characterizations of ZnO nanopowder synthesized by hydrothermal route using inorganic reactants  

NASA Astrophysics Data System (ADS)

Zinc oxide nanoscale powder has been synthesized by a hydrothermal route using zinc sulfate and sodium hydroxide. The as-prepared powder was annealed at 600 °C for 2 h and then characterized by X-ray diffraction (XRD), scanning electron microscopy and infra-red Fourier transformed spectroscopy. XRD measurements have shown a ZnO hexagonal wurtzite polycrystalline structure with good crystallinity and the formation of a new sodium pyrosulfate phase in the as-prepared powder. The annealing improves the crystalline quality of the powder and transforms the sodium pyrosulfate phase to a sodium sulfate one. The thermal treatment does not affect the lattice parameters and the Zn–O bond length but improves the random orientation of the ZnO crystallites growth. ZnO crystallites have an interconnected-nano-needles morphology forming irregular shaped aggregates. The size of the crystallites is about 20 nm. EDX analysis has shown the presence of C and S in addition to Zn and O. FTIR spectra confirm the formation of ZnO and sodium sulfate. The synthesized ZnO powder has a very high crystalline quality and the used method is a very advantageous one for the fabrication of nanosized metal oxides from inorganic reactants for photo-catalysis applications.

Djouadi, D.; Meddouri, M.; Chelouche, A.; Hammiche, L.; Aksas, A.

2014-12-01

242

Structural, morphological and interfacial characterization of Al-Mg/TiC composites  

SciTech Connect

Morphological and structural characterization of Al-Mg/TiC composites obtained by infiltration process and wetting by the sessile drop technique were studied. Focusing at the interface, wetting of TiC substrates by molten Al-Mg-alloys at 900 deg. C was investigated. Electron probe microanalysis (EPMA) indicated that aluminum carbide (Al{sub 4}C{sub 3}) is formed at the interface and traces of TiAl{sub 3} in the wetting assemblies were detected. Scanning Electron Microscopy (SEM) observations show that TiC particles do not appear to be uniformly attacked to produce a continuous layer of Al{sub 4}C{sub 3} at the interface. Molten Al-Mg-alloys were infiltrated into TiC preforms with flowing argon at a temperature of 900 deg. C. In the composites no reaction phase was observed by SEM. Quantification of the Al phase in the composite was carried out by X-ray diffraction (XRD) and Rietveld analysis. Chemical mapping analyzed by SEM shows that the Al-Mg alloy surrounds TiC particles. In the composites with 20 wt.% of Mg the Al-Mg-{beta} phase was detected through XRD.

Contreras, A. [Instituto Mexicano del Petroleo, Programa de Investigacion en Ductos, Corrosion y Materiales, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C. P. 07730, Mexico D.F. (Mexico)]. E-mail: acontrer@imp.mx; Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Programa de Investigacion en Ductos, Corrosion y Materiales, Eje Central Lazaro Cardenas 152, San Bartolo Atepehuacan, C. P. 07730, Mexico D.F. (Mexico); Flores, O. [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, P. O. Box 48-3, Cuernavaca, Mor (Mexico); Perez, R. [Instituto de Ciencias Fisicas, Universidad Nacional Autonoma de Mexico, P. O. Box 48-3, Cuernavaca, Mor (Mexico)

2007-08-15

243

Combined Effects of Ephedrine-Containing Dietary Supplements, Caffeine, and Nicotine on Morphology and Ultrastructure of Rat Hearts  

PubMed Central

Cigarette smokers have an increased risk for coronary artery disease. Nicotine present in cigarettes can adversely affect the cardiovascular system via stimulation of both sympathetic and parasympathetic neurons. Caffeine, another cardiovascular and central nervous system (CNS) stimulant, is commonly found in Ephedra and Ephedra-free dietary supplements. These caffeine-containing supplements also have been linked to cardiovascular toxicities. Although no longer on the U.S market, Ephedra-containing supplements are another source of cardiovascular and CNS stimulants, namely the ephedrine alkaloids. Together caffeine, nicotine, and ephedrine can individually stress the cardiovascular system, and an overlap of these agents is predicted in smokers and dieters. To understand the collective effects of these stimulants on the heart morphology and ultrastructure, rats were exposed to synthetic combinations of nicotine (0.2?mg/kg/day), ephedrine (0–30?mg/kg/day), and/or caffeine (0–24?mg/kg/day) as well as an extract from a caffeine-containing Ephedra supplement (Metabolife 356). After exposure for 3 days, the hearts were removed and examined for hypersensitivity myocarditis and myocardial necrosis. None of the drugs tested alone affected heart tissue morphology, nor were atypical cardiac cells observed. However, in combination, significant interactions were found between caffeine and ephedrine; the interventricular septum was most susceptible, with a significant increase in atypical cardiac cells observed. Nicotine pretreatment caused greater susceptibility to cardiotoxicity associated with combinations of caffeine + ephedrine or Metabolife, particularly in the left ventricle wall. These results indicate that sympathomimetic combinations present in Ephedra supplements may have produced cardiotoxicity reported in consumers of these products. Moreover, the presence of nicotine exacerbates these toxic effects. PMID:24761270

Brown, Christopher E.; Trauth, Stanley E.; Grippo, Richard S.; Gurley, Bill J.

2012-01-01

244

Morphological characterization of the spermatogonial subtypes in the neonatal mouse testis.  

PubMed

Spermatogenesis is the process of differentiation of diploid type A spermatogonia to haploid spermatozoa. Several subtypes of A spermatogonia have been characterized in the adult mouse testis. These include A-single (A(s)), A-paired (A(pr)), A-aligned (A(al)), and A1-A4. However, in the immature testis, very little information is available on subtypes and morphological features of type A spermatogonia. Six-day-old mouse testes, fixed either in Bouin solution or 5% glutaraldehyde, were embedded in paraffin and Epon, respectively. Thick sections (approximately 1 microm) of Epon-embedded tissue were stained with toluidine blue and revealed three subtypes of spermatogonia by light microscopy. The smallest spermatogonia (subtype I) appeared as single cells and exhibited a round or oval flattened nucleus with one or two prominent dense nucleoli and a characteristic unstained round and centrally located vacuole. These cells bound toluidine blue more avidly and appeared darker in comparison with the other cell types. Electron microscopy of thin sections (90 nm) revealed a finely granulated chromatin homogeneously distributed in the nucleus and sparse organelles in the cytoplasm. The second subtype of spermatogonia (subtype II) also displayed dark staining but was larger than subtype I; there was no central vacuole in the nucleus and heterochromatin clumps were observed. The largest subtype of spermatogonia (subtype III) showed large heterochromatin clumps and a pale staining nucleus. Intercellular bridges were noted between subtypes II and III. Based on the dye avidity, the three subtypes were classified as dark, transitional, and pale spermatogonia, respectively. Image analyses of 30 different cells of each subtype revealed a decline in gray-scale intensity from subtype I to III. Five-micrometer sections of paraffin-embedded tissue were immunoassayed with an antibody against the glial cell-derived neurotrophic factor family receptor alpha-1 (GFRalpha-1) receptor, a putative marker for undifferentiated spermatogonia, showing positive reaction only in germ cells. The pattern of GFRalpha-1 expression, coupled to the overall morphology of the cells, indicates that at this stage of development, mouse seminiferous tubules contain essentially A(s), A(pr), and possibly A(al) spermatogonia. Thus, the present study indicates the presence of subtypes of type A spermatogonia in the immature mouse testis similar to that described previously in adult monkey and man. PMID:12855601

Dettin, Luis; Ravindranath, Neelakanta; Hofmann, Marie-Claude; Dym, Martin

2003-11-01

245

Facile Synthesis and Characterization of BaFe12O19 Nanoparticles with Different Morphologies  

Microsoft Academic Search

The BaFe12O19 nanoparticles with different morphologies including plates, lamella, and rods have been prepared from a facile thermal pyrolysis of citrate precursors obtained from a spray-drying process. The additives and thermal history affect the morphology of BaFe12O19 nanopartilces. The lattice parameter values vary with the particle morphology especially for lattice parameter c, and the value is 23.235, 23.187, and 23.344 Ĺ

Gang Xue; Cairong Gong; Jinsheng Liang; Guangchuan Liang

2009-01-01

246

Morphological, biochemical, and histopathological indices and contaminant burdens of cotton rats (Sigmodon hispidus) at three hazardous waste sites near Houston, Texas, USA  

USGS Publications Warehouse

Male cotton rats (Sigmodon hispidus) were studied at three industrial waste sites near Houston, Texas, to determine whether various morphological, biochemical, and histopathological indices provided evidence of contaminant exposure and toxic insult. Only modest changes were detected in cotton rats residing at waste sites compared with reference sites. No single parameter was consistently altered, except hepatic cytochrome P-450 concentration which was lower ( [Formula: see text] ) at two waste sites, and tended to be lower ( [Formula: see text] ) at a third waste site. Elevated petroleum hydrocarbon concentrations were detected in rats at one waste site, but contaminant burdens of rats from the other sites were unremarkable. Unlike rats captured in summer, those trapped in winter exhibited hepatocellular hypertrophy and up to a 65% increase in liver: body weight ratio, cytochrome P-450 concentration, and activities of aniline hydroxylase, aryl hydrocarbon hydroxylase, and glutathione S-transferase. Although genotoxicity has been previously documented in cotton rats residing at two of the waste sites, biomarkers in the present study provided little evidence of exposure and damage

Rattner, B.A.; Flickinger, E.L.; Hoffman, D.J.

1993-01-01

247

The energy costs of sexual dimorphism in mole-rats are morphological not behavioural  

PubMed Central

Different reproductive strategies of males and females may lead to the evolution of differences in their energetic costs of reproduction, overall energetic requirements and physiological performances. Sexual dimorphism is often associated with costly behaviours (e.g. large males might have a competitive advantage in fighting, which is energetically expensive). However, few studies of mammals have directly compared the energy costs of reproductive activities between sexes. We compared the daily energy expenditure (DEE) and resting metabolic rate (RMR) of males and females of two species of mole-rat, Bathyergus janetta and Georychus capensis (the former is sexually dimorphic in body size and the latter is not) during a period of intense digging when males seek females. We hypothesized that large body size might be indicative of greater digging or fighting capabilities, and hence greater mass-independent DEE values in males of the sexually dimorphic species. In contrast to this prediction, although absolute values of DEE were greater in B. janetta males, mass-independent values were not. No differences were apparent between sexes in G. capensis. By comparison, although RMR values were greater in B. janetta than G. capensis, no differences were apparent between the sexes for either species. The energy cost of dimorphism is most likely to be the cost of maintenance of a large body size, and not the cost of behaviours performed when an individual is large. PMID:16519235

Scantlebury, M; Speakman, J.R; Bennett, N.C

2005-01-01

248

The morphological and biochemical effects of glibornuride on rat liver in experimental diabetes.  

PubMed

Glibornuride is a sulphonylurea derivative used as an oral hypoglycaemic drug in diabetics. The aim of this study was to examine the histological, ultrastructural and biochemical effects of glibornuride in streptozotocin (STZ)-treated rats. The animals were rendered diabetic by intraperitoneal injection of 65 mg/kg STZ. Fourteen days later, glibornuride was given at 5 mg/kg by gavage, daily for 28 days, to one STZ-diabetic and one control group. In the STZ-diabetic group, remarkable degenerative changes were observed. On the other hand, in the STZ-diabetic group given glibornuride, the degenerative changes decreased. In the STZ-diabetic group, blood glucose levels, serum aspartate transaminase activity, and total lipid levels increased, whereas the blood glutathione levels decreased. In contrast, in the STZ-diabetic group given glibornuride blood glucose levels, serum aspartate transaminase activity and total lipid levels decreased and blood glutathione levels increased. Significant changes in total protein levels in the serum were not observed in any group. As a conclusion, we can say that glibornuride has a protective effect against the hepatotoxicity produced by STZ-diabetes. PMID:15228018

Bolkent, S; Yanarda?, R; Karabulut-Bulan, O; Ozsoy-Saçan, O

2004-05-01

249

Morphological studies of bone and tendon. [in post-spaceflight rats  

NASA Technical Reports Server (NTRS)

The Soviet biosatellite Cosmos 2044 carried adult rats on a spaceflight that lasted 13.8 days and was intended to repeat animal studies carrier out on Cosmos 1887. Skeletal tissue and tendon from animals flown on Cosmos 2044 were studied by light and electron microscopy, histochemistry, and morphometric techniques. Studies were confined to the bone cells and vasculature from the weight-bearing tibias. Results indicated that vascular changes at the periosteal and subperiosteal region of the tibia were not apparent by light microscopy or histochemistry. However, electron microscopy indicated that vascular influsions were present in bone samples from the flight animals. A unique combination of microscopy and histochemical techniques indicated that the endosteal osteoblasts from this same middiaphyseal region demonstrated a slight (but not statisticallly significant) reduction in bone cell activity. Electron-microscopic studies of the tendons from metatarsal bones showed a collagen fibril disorganization as a result of spaceflight. Thus changes described for Cosmos 1887 were present in Cosmos 2044, but the changes ascribed to spaceflight were not as evident.

Doty, Stephen B.; Morey-Holton, Emily R.; Durnova, G. N.; Kaplanskii, A. S.

1992-01-01

250

Functional and morphological evidence of age-related denervation in rat laryngeal muscles.  

PubMed

Laryngeal muscle dysfunction compromises voice, swallowing, and airway protection in elderly adults. Laryngeal muscles and their motor neurons and their motor neurons communicate via the neuromuscular junction (NMJ). We tested the hypothesis that aging disrupts NMJ organization and function in the laryngeal thyroarytenoid (TA) and posterior cricoarytenoid (PCA) muscles We determined NMJ density and size and acetylcholine receptor (AChR) subunit mRNAs in TA and PCA muscles from 6-, 18-, and 30- month old-rats. NMJ function was determined with tubocurarine (TC) and contractions during nerve and muscle stimulation. NMJ size, abundance, and clustering decreased in 30-month TA and PCA muscles. AChRe mTNA and protein increased with age in both muscles. AChRg mRNA increased with age in both muscles while protein content increased in TA only. Aging PCA and TA were more sensitive to TC, demonstrating functional evidence of denervation. These results demonstrate that NMJs become smaller and less abundant in aging TA and PCA muscles. PMID:19223602

McMullen, Colleen A; Andrade, Francisco H

2009-04-01

251

The Effects of Taurine, Hypotaurine, and Taurine Homologs on Erythrocyte Morphology, Membrane Fluidity and Cytoskeletal Spectrin Alterations Due to Diabetes, Alcoholism and Diabetes-Alcoholism in the Rat  

Microsoft Academic Search

Taurine (TAU) and compounds representing a TAU analog (hypotaurine == HYTAU) or homolog (aminomethanesulfonic acid == AMSA,\\u000a homotaurine == HMTAU) were tested for their counteracting effects against alterations in erythrocyte (RBC) morphology, membrane\\u000a fluidity and cytoskeletal spectrin distribution due to diabetes, alcoholism and diabetes-alcoholism in male Goto-Kakizaki\\u000a rats (made diabetic with a high fat diet and alcoholic upon feeding on

Davekanand Gossai; Cesar A. Lau-Cam

252

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

PubMed Central

Recently a new rat model for type 2 diabetes the Zucker diabetic Sprague-Dawley (ZDSD/Pco) was created. In this study we sought to characterize the development of diabetic neuropathy in ZDSD rats using age-matched Sprague-Dawley rats as a control. Rats were examined at 34 weeks of age 12 weeks after the onset of hyperglycemia in ZDSD rats. At this time ZDSD rats were severely insulin resistant with slowing of both motor and sensory nerve conduction velocities. ZDSD rats also had fatty livers, elevated serum free fatty acids, triglycerides, and cholesterol, and elevated sciatic nerve nitrotyrosine levels. The corneas of ZDSD rats exhibited a decrease in subbasal epithelial corneal nerves and sensitivity. ZDSD rats were hypoalgesic but intraepidermal nerve fibers in the skin of the hindpaw were normal compared to Sprague-Dawley rats. However, the number of Langerhans cells was decreased. Vascular reactivity of epineurial arterioles, blood vessels that provide circulation to the sciatic nerve, to acetylcholine and calcitonin gene-related peptide was impaired in ZDSD rats. These data indicate that ZDSD rats develop many of the neural complications associated with type 2 diabetes and are a good animal model for preclinical investigations of drug development for diabetic neuropathy. PMID:25371906

Davidson, Eric P.; Coppey, Lawrence J.; Holmes, Amey; Lupachyk, Sergey; Dake, Brian L.; Oltman, Christine L.; Peterson, Richard G.; Yorek, Mark A.

2014-01-01

253

Quantitative Characterization of the Influence of the Nanoscale Morphology of Nanostructured Surfaces on Bacterial Adhesion and Biofilm Formation  

PubMed Central

Bacterial infection of implants and prosthetic devices is one of the most common causes of implant failure. The nanostructured surface of biocompatible materials strongly influences the adhesion and proliferation of mammalian cells on solid substrates. The observation of this phenomenon has led to an increased effort to develop new strategies to prevent bacterial adhesion and biofilm formation, primarily through nanoengineering the topology of the materials used in implantable devices. While several studies have demonstrated the influence of nanoscale surface morphology on prokaryotic cell attachment, none have provided a quantitative understanding of this phenomenon. Using supersonic cluster beam deposition, we produced nanostructured titania thin films with controlled and reproducible nanoscale morphology respectively. We characterized the surface morphology; composition and wettability by means of atomic force microscopy, X-ray photoemission spectroscopy and contact angle measurements. We studied how protein adsorption is influenced by the physico-chemical surface parameters. Lastly, we characterized Escherichia coli and Staphylococcus aureus adhesion on nanostructured titania surfaces. Our results show that the increase in surface pore aspect ratio and volume, related to the increase of surface roughness, improves protein adsorption, which in turn downplays bacterial adhesion and biofilm formation. As roughness increases up to about 20 nm, bacterial adhesion and biofilm formation are enhanced; the further increase of roughness causes a significant decrease of bacterial adhesion and inhibits biofilm formation. We interpret the observed trend in bacterial adhesion as the combined effect of passivation and flattening effects induced by morphology-dependent protein adsorption. Our findings demonstrate that bacterial adhesion and biofilm formation on nanostructured titanium oxide surfaces are significantly influenced by nanoscale morphological features. The quantitative information, provided by this study about the relation between surface nanoscale morphology and bacterial adhesion points towards the rational design of implant surfaces that control or inhibit bacterial adhesion and biofilm formation. PMID:21966403

Singh, Ajay Vikram; Vyas, Varun; Patil, Rajendra; Sharma, Vimal; Scopelliti, Pasquale Emanuele; Bongiorno, Gero; Podestŕ, Alessandro; Lenardi, Cristina; Gade, Wasudev Namdev; Milani, Paolo

2011-01-01

254

Prenatal stress and subsequent exposure to chronic mild stress influence dendritic spine density and morphology in the rat medial prefrontal cortex  

PubMed Central

Background Both prenatal stress (PS) and postnatal chronic mild stress (CMS) are associated with behavioral and mood disturbances in humans and rodents. The aim of this study was to reveal putative PS- and/or CMS-related changes in basal spine morphology and density of pyramidal neurons in the rat medial prefrontal cortex (mPFC). Results We show that rats exposed to PS and/or CMS display changes in the morphology and number of basal spines on pyramidal neurons in the mPFC. CMS had a negative effect on spine densities, particularly on spines of the mushroom type, which are considered to form stronger and more stable synapses than other spine types. PS alone did not affect spine densities, but had a negative effect on the ratio of mushroom spines. In addition, PS seemed to make rats less responsive to some of the negative effects of CMS, which supports the notion that PS represents a predictive adaptive response. Conclusion The observed changes may represent a morphological basis of PS- and CMS-related disturbances, and future studies in the field should not only consider total spine densities, but also separate between different spine types. PMID:18093285

Michelsen, Kimmo A; van den Hove, Daniël LA; Schmitz, Christoph; Segers, Olivier; Prickaerts, Jos; Steinbusch, Harry WM

2007-01-01

255

Morphology and connectivity of parabrachial and cortical inputs to gustatory thalamus in rats.  

PubMed

The ventroposterior medialis parvocellularis (VPMpc) nucleus of the thalamus, the thalamic relay nucleus for gustatory sensation, receives primary input from the parabrachial nucleus, and projects to the insular cortex. To reveal the unique properties of the gustatory thalamus in comparison with archetypical sensory relay nuclei, this study examines the morphology of synaptic circuitry in the VPMpc, focusing on parabrachiothalamic driver input and corticothalamic feedback. Anterogradely visualized parabrachiothalamic fibers in the VPMpc bear large swellings. At electron microscope resolution, parabrachiothalamic axons are myelinated and make large boutons, forming multiple asymmetric, adherent, and perforated synapses onto large-caliber dendrites and dendrite initial segments. Labeled boutons contain dense-core vesicles, and they resemble a population of terminals within the VPMpc containing calcitonin gene-related peptide. As is typical of primary inputs to other thalamic nuclei, parabrachiothalamic terminals are over five times larger than other inputs, while constituting only 2% of all synapses. Glomeruli and triadic arrangements, characteristic features of other sensory thalamic nuclei, are not encountered. As revealed by anterograde tracer injections into the insular cortex, corticothalamic projections in the VPMpc form a dense network of fine fibers bearing small boutons. Corticothalamic terminals within the VPMpc were also observed to synapse on cells that were retrogradely filled from the same injections. The results constitute an initial survey describing unique anatomical properties of the rodent gustatory thalamus. J. Comp. Neurol. 523:139-161, 2015. © 2014 Wiley Periodicals, Inc. PMID:25186035

Holtz, Stephen L; Fu, Anqi; Loflin, Wyatt; Corson, James A; Erisir, Alev

2015-01-01

256

Changes in Retinal Morphology, Electroretinogram and Visual Behavior after Transient Global Ischemia in Adult Rats  

PubMed Central

The retina is a light-sensitive tissue of the central nervous system that is vulnerable to ischemia. The pathological mechanism underlying retinal ischemic injury is not fully understood. The purpose of this study was to investigate structural and functional changes of different types of rat retinal neurons and visual behavior following transient global ischemia. Retinal ischemia was induced using a 4-vessel occlusion model. Compared with the normal group, the number of ?III-tubulin positive retinal ganglion cells and calretinin positive amacrine cells were reduced from 6 h to 48 h following ischemia. The number of recoverin positive cone bipolar cells transiently decreased at 6 h and 12 h after ischemia. However, the fluorescence intensity of rhodopsin positive rod cells and fluorescent peanut agglutinin positive cone cells did not change after reperfusion. An electroretinogram recording showed that the a-wave, b-wave, oscillatory potentials and the photopic negative response were completely lost during ischemia. The amplitudes of the a- and b-waves were partially recovered at 1 h after ischemia, and returned to the control level at 48 h after reperfusion. However, the amplitudes of oscillatory potentials and the photopic negative response were still reduced at 48 h following reperfusion. Visual behavior detection showed there was no significant change in the time spent in the dark chamber between the control and 48 h group, but the distance moved, mean velocity in the black and white chambers and intercompartmental crosses were reduced at 48 h after ischemia. These results indicate that transient global ischemia induces dysfunction of retinal ganglion cells and amacrine cells at molecular and ERG levels. However, transient global ischemia in a 17 minute duration does not appear to affect photoreceptors. PMID:23776500

Zhao, Ying; Yu, Bo; Xiang, Yong-Hui; Han, Xin-Jia; Xu, Ying; So, Kwok-Fai; Xu, An-Ding; Ruan, Yi-Wen

2013-01-01

257

Morphologic and molecular characterization of Salmonella typhimurium infection in neonatal calves.  

PubMed

The host response to Salmonella plays a major role in the outcome of infection. The present study was undertaken to further characterize Salmonella typhimurium infection in neonatal calves at both the morphologic and the molecular level using the ligated ileal loop model. Eight 4-5-week-old male Holstein calves underwent laparotomy, and loops were prepared in the ileum. The loops were either inoculated with an S. typhimurium strain pathogenic for cattle or injected with sterile LB broth as control. Samples for histology, transmission and scanning electron microscopy, and RNA extraction were collected at various time points between 5 minutes and 12 hours postinfection. Invasion of both M cells and enterocytes began at 15 minutes postinfection. No specific cell type was the main target for invasion. Intracellular bacteria were observed in the lamina propria after 1 hour postinfection. A severe acute neutrophilic response was associated with invasion of the Peyer's patches. Upregulated expression of CXC chemokines (interleukin [IL]-8, growth-related oncogenes, [GRO] alpha and gamma, and granulocyte chemotactic protein [GCP]2) was detected by reverse transcription polymerase chain reaction beginning at 1 hour postinfection. Expression of proinflammatory (IL-1beta, IL-18, and tumor necrosis factor [TNF]alpha) and anti-inflammatory (IL-10, IL-IRa, and IL-4) cytokines was also assessed. A marked increase in expression of IL-1beta was observed, whereas the profile of expression of IL-18 and TNFalpha did not change after infection. Upregulation of IL-1Ra and IL-4 but not of IL-10 was observed. These findings indicate that infection of bovine ligated ileal loops with S. typhimurium results in an acute neutrophilic inflammatory response that is associated with the upregulation of CXC chemokines (IL-8, GROalpha and gamma, and GCP2), IL-1beta, IL-IRa, and IL-4. PMID:12009058

Santos, R L; Zhang, S; Tsolis, R M; Bäumler, A J; Adams, L G

2002-03-01

258

Cloning and Characterization of Rat Pancreatic ?-Cell\\/Liver Type Glucose Transporter Gene: A Unique Exon\\/Intron Organization  

Microsoft Academic Search

Four overlapping ? genomic clones encoding rat pan- creatic ?-cell\\/liver type glucose transporter (GLUT2) have been isolated and characterized. The gene is about 35 kb long and contains 14 exons and 13 introns. Contrary to the exon 1 of the human or mouse counterpart, the rat GLUT2 gene has three additional noncoding exons which were identified by 5?-RACE and all

Yong-ho Ahn; Jae-woo Kim; Gil-soo Han; Byung-gwan Lee; Yoon-soo Kim

1995-01-01

259

Ultrasound method applied to characterize healthy femoral diaphysis of Wistar rats in vivo  

PubMed Central

A simple experimental protocol applying a quantitative ultrasound (QUS) pulse-echo technique was used to measure the acoustic parameters of healthy femoral diaphyses of Wistar rats in vivo. Five quantitative parameters [apparent integrated backscatter (AIB), frequency slope of apparent backscatter (FSAB), time slope of apparent backscatter (TSAB), integrated reflection coefficient (IRC), and frequency slope of integrated reflection (FSIR)] were calculated using the echoes from cortical and trabecular bone in the femurs of 14 Wistar rats. Signal acquisition was performed three times in each rat, with the ultrasound signal acquired along the femur's central region from three positions 1 mm apart from each other. The parameters estimated for the three positions were averaged to represent the femur diaphysis. The results showed that AIB, FSAB, TSAB, and IRC values were statistically similar, but the FSIR values from Experiments 1 and 3 were different. Furthermore, Pearson's correlation coefficient showed, in general, strong correlations among the parameters. The proposed protocol and calculated parameters demonstrated the potential to characterize the femur diaphysis of rats in vivo. The results are relevant because rats have a bone structure very similar to humans, and thus are an important step toward preclinical trials and subsequent application of QUS in humans. PMID:24838643

Fontes-Pereira, A.; Matusin, D.P.; Rosa, P.; Schanaider, A.; von Krüger, M.A.; Pereira, W.C.A.

2014-01-01

260

Electrophysiological characterization of entopeduncular nucleus neurons in anesthetized and freely moving rats  

PubMed Central

The EntoPeduncular nucleus (EP), which is homologous to the internal segment of the Globus Pallidus (GPi) in primates, is one of the two basal ganglia (BG) output nuclei. Despite their importance in cortico-BG information processing, EP neurons have rarely been investigated in rats and there is no available electrophysiological characterization of EP neurons in vivo. We recorded and analyzed the activity of EP neurons in freely moving as well as anesthetized rats, and compared their activity patterns. Examination of neuronal firing statistics during wakefulness suggested that similar to neurons recorded in the primate GPi, EP neurons are a single population characterized by Poisson-like firing. Under isoflurane anesthesia the firing rate of EP neurons decreased substantially and their coefficient of variation and relative duration of quiescence periods increased. Investigation of the relationship between firing rate and depth of anesthesia revealed two distinct neuronal groups: one that decreased its firing rate with the increase in anesthesia level, and a second group where the firing rate was independent of anesthesia level. Post-hoc examination of the firing properties of the two groups showed that they were statistically distinct. These results may thus help reconcile in vitro studies in rats and primates which have reported two distinct neuronal populations, and in vivo studies in behaving primates indicating one homogeneous population. Our data support the existence of two distinct neuronal populations in the rat EP that can be distinguished by their characteristic firing response to anesthesia. PMID:24574980

Benhamou, Liora; Cohen, Dana

2014-01-01

261

SERUM HORMONE CHARACTERIZATION AND EXOGENEOUS HORMONE RESCUE OF BROMODICHLOROMETHANE-INDUCED PREGNANCY LOSS IN THE F344 RAT  

EPA Science Inventory

SERUM HORMONE CHARACTERIZATION AND EXOGENEOUS HORMONE RESCUE OF BROMODICHLOROMETHANE-INDUCED PREGNANCY LOSS IN THE F344 RAT Susan R. Bielmeier*, Deborah S. Best^, and Michael G. Narotsky^ ABSTRACT Previously, we demonstrated that bromodichloromethane (BDCM), a d...

262

Characterizing operant hyperactivity in the Spontaneously Hypertensive Rat  

PubMed Central

Background Operant hyperactivity, the emission of reinforced responses at an inordinately high rate, has been reported in children with ADHD and in the Spontaneously Hypertensive Rat (SHR), the most widely studied animal model of ADHD. The SHR emits behavior at hyperactive levels, relative to a normoactive strain, only when such behavior is seldom reinforced. Because of its dependence on rate of reinforcement, operant hyperactivity appears to be driven primarily by incentive motivation, not motoric capacity. This claim was evaluated in the present study using a novel strategy, based on the organization of behavior in bouts of reinforced responses separated by pauses. Method Male SHR, Wistar-Kyoto (WKY) and Wistar rats (WIS) were exposed each to a multiple variable-interval schedule of sucrose reinforcement (12, 24, 48, 96, and 192 s) between post-natal days (PND) 48 and 93. Responding in each schedule was examined in two epochs, PND 58-62 and 89-93. Parameters of response-reinforcement functions (Herrnstein's hyperbola) and bout-organized behavior were estimated in each epoch. Results SHR emitted higher response rates than WKY and WIS, but only when rate of reinforcement was low (fewer than 2 reinforcers per minute), and particularly in the second epoch. Estimates of Herrnstein's hyperbola parameters suggested the primacy of motivational over motoric factors driving the response-rate differential. Across epochs and schedules, a more detailed analysis of response bouts by SHR revealed that these were shorter than those by WKY, but more frequent than those by WKY and WIS. Differences in bout length subsided between epochs, but differences in bout-initiation rate were exacerbated. These results were interpreted in light of robust evidence linking changes in bout-organization parameters and experimental manipulations of motivation and response-reinforcement contingency. Conclusions Operant hyperactivity in SHR was confirmed. Although incentive motivation appears to play an important role in operant hyperactivity and motoric capacity cannot be ruled out as a factor, response-bout patterns suggest that operant hyperactivity is primarily driven by steeper delay-of-reinforcement gradients. Convergence of this conclusion with theoretical accounts of ADHD and with free-operant performance in children with ADHD supports the use of SHR as an animal model of ADHD. PMID:22277367

2012-01-01

263

Purification and characterization of salicylhydroxamic acid reductase from rat liver.  

PubMed

Salicylhydroxamic acid reductase, which catalyzes the reduction of salicylhydroxamic acid to salicylamide, was purified from rat liver cytosol. The purification procedure consisted of fractionation with ammonium sulfate, chromatography with Phenyl-Toyopearl 650, DEAE-cellulose, hydroxyapatite, and Sephadex G-200, and chromatofocusing with PBE94. The molecular weight of the enzyme was estimated to be about 140,000 by Sephadex G-200 gel filtration and 152,000 by polyacrylamide gel electrophoresis. The enzyme was dissociated into two different subunits with estimated molecular weights of 41,000 and 32,000, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These facts suggested that the enzyme is a heterotetramer consisting of two pairs of two nonidentical polypeptide chains. The Km value of the enzyme for salicylhydroxamic acid was estimated to be 91.5 or 88.7 microM in the presence of NADH or NADPH, respectively. The isoelectric point of the enzyme is pH 5.4. The enzyme was highly specific for salicylhydroxamic acid, but it also showed some activity with other hydroxamic acids such as nicotinohydroxamic acid and N-hydroxy-2-acetylaminofluorene. The enzyme activity was inhibited by allopurinol, oxipurinol, dicumarol, menadione, p-chloromercuribenzoic acid, sodium arsenite, potassium cyanide, cupric sulfate, and disulfiram, but little inhibition was observed with oxygen. PMID:8489240

Katsura, H; Kitamura, S; Tatsumi, K

1993-05-01

264

Isolation and characterization of the rat huntingtin promoter.  

PubMed Central

Huntington's disease (HD) is a neurodegenerative disorder caused by a (CAG)>37 repeat expansion in a novel gene of unknown function. Although the huntingtin gene is expressed in neuronal and non-neuronal tissues, the disease affects nerve cells of selected regional areas of the central nervous system. To gain insight into the regulation of the HD gene we analysed 1348 bp of the rat huntingtin promoter region. This region lacks a TATA and a CAAT box, is rich in GC content and has several consensus sequences for binding sites for SP1, PEA3, Sif and H2A. The stretch between nucleotides -56 and -206 relative to the first ATG is highly conserved between human and rodents and it harbours several potential binding sites for transcription factors. We analysed deletion mutants fused with the chloramphenicol acetyltransferase reporter gene in transfected, HD-expressing neuronal (NS20Y, NG108-15) and non-neuronal Chinese hamster ovary cell lines. Hence these cells should contain the required trans-acting factors necessary for HD gene expression. Partial deletion of the evolutionarily conserved part of the promoter significantly decreases the activity in both neuronal and non-neuronal cells, indicating that the core promoter activity is located between nucleotides -332 and -15. DNase I footprinting and electrophoretic mobility-shift assays were used to define the nucleotide positions and binding affinity of DNA-protein interactions. PMID:9806905

Holzmann, C; Mäueler, W; Petersohn, D; Schmidt, T; Thiel, G; Epplen, J T; Riess, O

1998-01-01

265

Continuous Electrical Current and Zinc Sulphate Administered by Transdermal Iontophoresis Improves Skin Healing in Diabetic Rats Induced by Alloxan: Morphological and Ultrastructural Analysis  

PubMed Central

Purpose. Evaluated the effects of continuous electrical current (CEC) or zinc administrated by transdermal iontophoresis (Zn+TDI). Methods. 120 male Wistar rats were submitted to an incision surgery at the anterior region of abdomen and distributed into 6 experimental groups with 40 animals: 3 diabetic groups and 3 normal groups, untreated and treated with CEC alone or with Zn + TDI. Each group was further divided into 4 subgroups with 10 rats each to be evaluated on the 4th, 7th, 14th, and 21st day after surgery. In each period, clinical and laboratory parameters from the animals were analyzed. Results. The analysis by optical and scanning electron microscopy showed a delay in the phases of wound healing in diabetic rats without treatment in all periods of the experiment; breaking strength (BS) was significantly reduced in skin scars of untreated diabetic rats when compared to other groups. In contrast, BS in skin scars of nondiabetic groups and diabetic rats treated with Zn + TDI showed significant increase in those, besides not presenting delayed healing. Conclusion. Electrical stimulation of surgical wounds used alone or in association with zinc by TDI is able to consistently improve the morphological and ultrastructural changes observed in the healing of diabetic animals. PMID:25254221

Colli Rocha Dias, Pedro; Natália Lucchesi, Amanda; Ferraz de Arruda, Maurício; Veruska Paiva Ortolan, Érika; Marques, Mariângela Esther A.; Spadella, César Tadeu

2014-01-01

266

Characterizing Morphology and Erosional Trends of Permafrost Bluffs, Barter Island, Alaska  

NASA Astrophysics Data System (ADS)

Recession of coastal permafrost bluffs along portions of the North Slope of Alaska are highly variable, and recent studies have found increased retreat rates since the early 2000s along the western Beaufort Sea coastline, yet the mechanisms and processes driving the increased retreat rates remain poorly understood. The Native village of Kaktovik and adjacent U.S. Air Force radar site are situated on Barter Island and bound by an eroding coastal bluff where attempts to control bluff erosion with shore protection structures were undertaken more than a decade ago. In an effort to gain insight into the physical controls driving or limiting bluff recession in this region, a suite of field data was collected in August 2010 to characterize the beaches, bluffs, and nearshore setting. Data collected at 13 transect locations along the 3 km section of coastal bluffs include general bluff morphology and stratigraphy, detailed surveys of bluff edge and bluff face morphology, sediment grain size of the fronting beach, water/ice content and sediment grain size of the massive ice within the bluffs, and nearshore bathymetry. The bluffs here range in height from a few meters to more than ten meters and consist of a very complex sequence of material ranging from dense marine clay at the base, sands and gravel thought to be of fluvial origin, massive units of sand of unknown origin, massive ice which has recently been interpreted as buried glacial ice, wedge ice, thermokarst cave ice, aeolian silts and sands, and peat. At one site, thermistor arrays were installed to evaluate temperature gradients in response to solar radiation and heat flux transfers through characteristic bluff material. Aerial lidar DEMs obtained in 2009 (USGS) revealed a rise in bluff elevation across the central portion of the island where field observations of bluff stratigraphy showed multi-layered stratification. At the lower elevation outer flanks the exposed bluff face consisted of homogenous layers of sandy-silt below the surface peat layer. Comparison of historical bluff edge lines (1947, 1987, 2003), 2009 lidar derived bluff lines, and differential GPS surveys collected in August 2010 suggest increased erosion rates of the bluff top in recent years near the topographically-higher central portion of the island. Maximum beach widths were observed at the flanks of the island where east-west trending spits have formed, likely by way of longshore transport driven by variations in wave direction at the terminus of the spits. Beach width ranged from a maximum of 80 m at the eastern boundary of the bluffs to no beach in front of the former radar station landfill where shore protection structures are emplaced. Beach surface material consisted of fine sands in the back beach region and gravels to pebble-sized material in the mid-beach and swash zone areas. Primary failure modes of Barter Island bluffs appear to be a combination of thermal degradation and thawing of permafrost in the exposed bluff face, mechanical and thermal niching at the toe, followed by rotational slumping of the higher bluffs near the central portion of the island and block collapse of the lower bluffs at the flanks of the island.

Gibbs, A.; Erikson, L. H.; Jones, B.; Richmond, B. M.

2010-12-01

267

Spatial and temporal morphological changes in the subarachnoid space after graded spinal cord contusion in the rat.  

PubMed

Spontaneous repair or treatment-induced recovery after spinal cord injury (SCI) is very limited and might be related to extramedullary alterations that have only briefly been documented. Here we report on the morphological changes of the spinal subarachnoid space (SAS) in a clinically relevant model of SCI. Anesthetized rats were subjected either to mild or severe spinal cord contusion at T9. Spine blocks from the site of injury and adjacent segments were harvested at acute (1 h and 1 day [d]), subacute (3 and 7 d), and chronic (1 and 3 months) stages post-injury. Histopathology and morphometry at each decalcified vertebral level were assessed. At acute and subacute stages, reduction of SAS lumen was observed after both mild and severe injuries. Acutely, after severe injuries, SAS occlusion was associated mainly with cord swelling and subarachnoid hematomas; a trend for dural sac constriction was observed for mild injuries. At 7 d, cord swelling diminished in both instances, but dural sac constriction increased for severe injuries. At early stages, in the epicenter and vicinity, histopathology revealed compression of neurovascular elements within the SAS, which was more intense in severe than in mild injuries. In the chronic stage, SAS lumen increased notably, mostly from cord atrophy, despite dural sac constriction. Myelograms complemented observations made on SAS lumen permeability. Post-traumatic arachnoiditis occurred mainly in animals with severe injury. In conclusion, early extramedullary SAS changes described here might be expected to produce alterations in cerebrospinal fluid (CSF) dynamics and cord blood perfusion, thereby contributing to the pathophysiology of SCI and becoming novel targets for treatment. PMID:23472674

Reyes-Alva, Horacio J; Franco-Bourland, Rebecca E; Martinez-Cruz, Angelina; Grijalva, Israel; Madrazo, Ignacio; Guizar-Sahagun, Gabriel

2013-06-15

268

Chemical, dimensional and morphological ultrafine particle characterization from a waste-to-energy plant.  

PubMed

Waste combustion processes are responsible of particles and gaseous emissions. Referring to the particle emission, in the last years specific attention was paid to ultrafine particles (UFPs, diameter less than 0.1 ?m), mainly emitted by combustion processes. In fact, recent findings of toxicological and epidemiological studies indicate that fine and ultrafine particles could represent a risk for health and environment. Therefore, it is necessary to quantify particle emissions from incinerators also to perform an exposure assessment for the human populations living in their surrounding areas. To these purposes, in the present work an experimental campaign aimed to monitor UFPs was carried out at the incineration plant in San Vittore del Lazio (Italy). Particle size distributions and total concentrations were measured both at the stack and before the fabric filter inlet in order to evaluate the removal efficiency of the filter in terms of UFPs. A chemical characterization of UFPs in terms of heavy metal concentration was performed through a nuclear method, i.e., Instrumental Neutron Activation Analysis (INAA), as well as a mineralogical investigation was carried out through a Transmission Electron Microscope (TEM) equipped with an Energy Dispersive Spectrometer (EDS) in order to evaluate shape, crystalline state and mineral compound of sampled particles. Maximum values of 2.7 × 10(7) part. cm(-3) and 2.0 × 10(3) part. cm(-3) were found, respectively, for number concentration before and after the fabric filter showing a very high efficiency in particle removing by the fabric filter. With regard to heavy metal concentrations, the elements with higher boiling temperature present higher concentrations at lower diameters showing a not complete evaporation in the combustion section and the consequent condensation of semi-volatile compounds on solid nuclei. In terms of mineralogical and morphological analysis, the most abundant compounds found in samples collected before the fabric filter are Na-K-Pb oxides followed by phyllosilicates, otherwise, different oxides of comparable abundance were detected in the samples collected at the stack. PMID:21802934

Buonanno, Giorgio; Stabile, Luca; Avino, Pasquale; Belluso, Elena

2011-11-01

269

Sensory and Motor Characterization in the Post-natal Valproate Rat Model of Autism  

PubMed Central

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. 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 post-natally treated with valproate. Thirty four rat pups were injected with either valproate (150 mg/kg) or saline on post-natal 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 under-responsive to auditory stimuli, showed deficits in auditory sensory gating, and demonstrated impairments in motor speed and performance. These findings suggest that post-natal valproate treatment elicits sensory and motor features often seen in individuals with ASD. Further, the hypo-sensitivity seen in post-natally valproate-treated rats contrasted with hyper-sensitivity previously reported in pre-natally 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 sensory-motor impairments in ASD. PMID:22627078

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

2013-01-01

270

Molecular and morphological characterization of myxozoan actinospore types from a commercial catfish pond in the Mississippi delta.  

PubMed

Abstract :? The actinospore diversity of infected Dero digitata was surveyed (May 2011) from a channel catfish ( Ictalurus punctatus ) production pond in the Mississippi Delta region for the elucidation of unknown myxozoan life cycles. At present, only 2 myxozoan life cycles have been molecularly confirmed in channel catfish, linking the actinospore stage from an aquatic oligochaete ( D. digitata ) and the myxospore stage from the catfish. In this study D. digitata (n = 2,592) were isolated from oligochaetes collected from the bottom sediment of a channel catfish production pond. After 1 wk of daily observation, a total of 6 genetically different actinospore types were observed. The collective groups were classified as 2 aurantiactinomyxons, 2 helioactinomyxons, 1 raabeia, and 1 triactinomyxon. Overall prevalence of myxozoan infections in the isolated oligochaetes was 4.4%. Actinospores were photographed and measured for morphological characterization. Four previously undescribed actinospore types were identified and characterized molecularly and morphologically. Phylogenetic analysis revealed the raabeia and one of the helioactinomyxon (type 1) actinospores were closely related to the group of myxozoans known to parasitize ictalurids in North America. To date, no myxospores have been linked to the newly sequenced actinospores reported in this survey. The morphological and molecular data generated from this study will assist in the identification of myxospore counterparts for these actinospore stages and aid in the elucidation of unknown myxozoan life cycles in closed production systems. PMID:25003942

Rosser, Thomas G; Griffin, Matt J; Quiniou, Sylvie M A; Greenway, Terrence E; Khoo, Lester H; Wise, David J; Pote, Linda M

2014-12-01

271

Modifications in rat testicular morphology and increases in IFN-gamma serum levels by the oral administration of subtoxic doses of mercuric chloride.  

PubMed

Mercury induces structural and functional damage in several organs, however the effects of subtoxic doses of the metal on the male reproductive system are not well defined. In order to analyze testicular and epididymal morphological alterations and changes in IL-4 or IFN-gamma serum levels, adult male Sprague-Dawley rats received 0.01, 0.05 or 0.1 microg/ml of mercuric chloride (HgCl(2)) in deionized water for 1 to 7 months by oral route. Controls received deionized water alone. Twenty rats, separated in four groups of five animals each, were used per time of exposure. Progressive degenerative lesions consisting of lack of germ cell cohesion and desquamation, arrest at spermatocyte stage and hypospermatogenesis were observed in seminiferous epithelium by light and electron microscopy. Leydig cells showed cytoplasmic vacuolation and nuclear signs of cell death. Loss of peritubular cell aggregation was evidenced in the epididymis. Mercury accumulation was detected in both organs by mass spectroscopy. Rats showed enhanced IFN-gamma serum levels as compared to controls but only reached significance after 7 months of mercury administration. Subtoxic doses of inorganic mercury could lead to reproductive and immunological alterations. The results demonstrate that sublethal concentrations of mercuric chloride are enough to induce morphological and ultrastructural modifications in male reproductive organs. These contribute to functional alterations of spermatogenesis with arrest at spermatocyte stage, hypospermatogenesis and possibly impaired steroidogenesis which together could affect male fertility. PMID:19462287

Penna, Salvador; Pocino, Marisol; Marval, Maria Josefina; Lloreta, José; Gallardo, Luis; Vila, Joan

2009-01-01

272

Impact of adrenalectomy and dexamethasone treatment on testicular morphology and sperm parameters in rats: insights into the adrenal control of male reproduction.  

PubMed

Here we investigated the hypothesis that normal levels of glucocorticoids, a class of adrenal steroid hormones, are required for normal testicular and epididymal functions. We examined the effects of the manipulation of glucocorticoid plasma levels by bilateral adrenalectomy (1, 2, 7 and 15 days) alone or in combination with daily treatment with the synthetic glucocorticoid dexamethasone (DEX; 5 ?g/kg, i.p., 6 days) on the morphology of the testis and sperm parameters in rats. We showed that adrenalectomy led to a reduction in testicular sperm count and daily sperm production starting 2 days after surgery and a differential decrease in sperm count in the epididymis, according to the region and time post-adrenalectomy analysed. In parallel, testes from 7-day adrenalectomized (ADX) rats displayed a higher frequency of damaged seminiferous tubules and the presence of elongated spermatids retained in the basal epithelial compartment in stages IX-XVII, which is indicative of defective spermiation. The alkaline comet assay revealed a late effect of adrenalectomy on epididymal sperm DNA fragmentation, which was increased only 15 days after surgery. DEX treatment prevented the changes in testicular and epididymal sperm count observed in 7-day ADX rats, but failed to protect the testis from ADX-induced morphological abnormalities. Thus, our results indicated that glucocorticoids may be involved in events related to the maintenance of spermatogenesis and sperm maturation during adulthood. These findings provide new insights into the importance of adrenal steroids to male fertility. PMID:24925687

Silva, E J R; Vendramini, V; Restelli, A; Bertolla, R P; Kempinas, W G; Avellar, M C W

2014-11-01

273

Identification and characterization of a rat macrophage inflammatory protein-1alpha receptor.  

PubMed

A macrophage inflammatory protein-1alpha (MIP-1alpha) receptor has been cloned from rat (Rattus norvegicus) genomic DNA by PCR using oligonucleotides based on the mouse CCR1 DNA sequence and expressed in HEK293 cells to enable its characterization. The receptor was cloned three times in independent experiments to generate a consensus sequence. The rat ccrl receptor amino acid sequence is 92% identical to mouse and 80% identical to human CCR1. A consensus clone was transfected into HEK293 cells using the expression vector pIRES, and stable receptor expressing cell lines were isolated. In competitive receptor binding assays using iodinated human MIP-1alpha, rat ccrl binds hMIP-1alpha, hMIP-1beta, and hMCP-3, but not hRANTES or human interleukin-8 (hIL-8). We have been unable to demonstrate calcium mobilization by rat ccrl in HEK293 cells using human chemokines as ligands. Therefore, we have adopted lowercase nomenclature for the receptor until signaling is observed. This receptor and cell line may be of use in the preclinical development of CCR1 antagonists. PMID:11091494

Waller, A; Nayee, P; Czaplewski, L G

2000-10-01

274

Characterizing assembly morphology changes during solubilization process of dimyristoyl phosphocholine vesicles by n-dodecyl triethylammonium bromide.  

PubMed

In the present work, the assembly morphology changes during the solubilization process of the sonicated unilamellar vesicles from dimyristoyl phosphocholine (DMPC) by a cationic surfactant, n-dodecyl triethylammonium bromide (DTEAB) were well characterized with DSC, FF-TEM and DLS and fluorescence probes technique. Based on an analysis on the above results, a primary multi-stage model was brought forward to sketch the assembly morphology changes during the DMPC vesicle solubilization by DTEAB. In comparison with classical models, vesicles division, tubule-like structure formation and fission to vesicle were found in the middle stages of this model. Additionally, it is the first time that the transversally-cut profiles of tubule-like structures were observed during vesicle solubilization process. PMID:17376471

Wang, Shaoqing; Huang, Jianbin; Song, Qian; Fu, Honglan

2007-07-01

275

Chronic Administration of the Neurotrophic Agent Cerebrolysin Ameliorates the Behavioral and Morphological Changes Induced by Neonatal Ventral Hippocampus Lesion in a Rat Model of Schizophrenia  

PubMed Central

Neonatal ventral hippocampal lesion (nVHL) in rats has been widely used as a neurodevelopmental model to mimic schizophrenia-like behaviors. Recently, we reported that nVHLs result in dendritic retraction and spine loss in prefrontal cortex (PFC) pyramidal neurons and medium spiny neurons of the nucleus accumbens (NAcc). Cerebrolysin (Cbl), a neurotrophic peptide mixture, has been reported to ameliorate the synaptic and dendritic pathology in models of aging and neurodevelopmental disorder such as Rett syndrome. This study sought to determine whether Cbl was capable of reducing behavioral and neuronal alterations in nVHL rats. The behavioral analysis included locomotor activity induced by novel environment and amphetamine, social interaction, and sensoriomotor gating. The morphological evaluation included dendritic analysis by using the Golgi-Cox procedure and stereology to quantify the total cell number in PFC and NAcc. Behavioral data show a reduction in the hyperresponsiveness to novel environment- and amphetamine-induced locomotion, with an increase in the total time spent in social interactions and in prepulse inhibition in Cbl-treated nVHL rats. In addition, neuropathological analysis of the limbic regions also showed amelioration of dendritic retraction and spine loss in Cbl-treated nVHL rats. Cbl treatment also ameliorated dendritic pathology and neuronal loss in the PFC and NAcc in nVHL rats. This study demonstrates that Cbl promotes behavioral improvements and recovery of dendritic neuronal damage in postpubertal nVHL rats and suggests that Cbl may have neurotrophic effects in this neurodevelopmental model of schizophrenia. These findings support the possibility that Cbl has beneficial effects in the management of schizophrenia symptoms. PMID:21932359

Vázquez-Roque, Rubén Antonio; Ramos, Brenda; Tecuatl, Carolina; Juárez, Ismael; Adame, Anthony; de la Cruz, Fidel; Zamudio, Sergio; Mena, Raúl; Rockenstein, Edward; Masliah, Eliezer; Flores, Gonzalo

2012-01-01

276

Characterization of glomerular thromboxane receptor sites in the rat.  

PubMed

The aim of this study was to identify and characterize thromboxane (Tx) receptor sites in renal glomeruli. Binding studies were performed on freshly isolated glomeruli using the stable TxA2 receptor antagonist, [3H]SQ 29548. Specific binding was saturable, reversible, and varied with glomerular protein. Scatchard plots revealed a single class of high-affinity receptor sites (Kd = 14.3 +/- 2.4 nM, Bmax = 361 +/- 22 fmol/mg; n = 5). Specific binding was inhibited by Tx agonists (U-46619 and U-44069) and antagonist (SQ 29548) and was highly specific for Tx, since prostaglandin (PG)E2 and PGF2 alpha were 1,000-fold less potent in inhibiting binding. In vivo, U-46619 (1.75 micrograms.kg-1.min-1) was without effect on mean arterial pressure, but reduced renal blood flow by 71% (P less than 0.01) and glomerular filtration rate by 67% (P less than 0.01) and increased filtration fraction by 24% (P less than 0.05). SQ 29548 (10 micrograms.kg-1.min-1) completely blocked the renal effects of U-46619. These studies demonstrate the presence of specific receptor sites for Tx on renal glomeruli that are linked to modulation of renal hemodynamics. PMID:2525345

Wilkes, B M; Solomon, J; Maita, M; Mento, P F

1989-06-01

277

Molecular and morphological characterization of Globodera populations from Oregon and Idaho  

Technology Transfer Automated Retrieval System (TEKTRAN)

An unusual population of cyst nematode was found in soils collected from a Powell Butte, Oregon field with a cropping history including potatoes, wheat, other crops, and significant weed presence. Morphologically, these nematodes possessed characteristics that collectively set them apart from known ...

278

Morphological and molecular characterization of Globodera populations from Oregon and Idaho  

Technology Transfer Automated Retrieval System (TEKTRAN)

A new species of Globodera, identified from three potato fields, is described herein as Globodera pseudopallida n. sp. Morphologically, G. pseudopallida n. sp. exhibits some unique features that are not consistent between populations; but molecularly, G. pseudopallida n. sp. is distinct from G. pall...

279

Analysis of LiDAR-derived topographic information for characterizing and differentiating landslide morphology and activity  

Microsoft Academic Search

This study used airborne laser altimetry (LiDAR) to examine the surface morphology of two canyon-rim landslides in southern Idaho. The high resolution topographic data were used to calculate surface roughness, slope, semivariance, and fractal dimension. These data were combined with historical movement data (Global Positioning Systems (GPS) and laser theodolite) and field observations for the currently active landslide, and the

Nancy F. Glenn; David R. Streutker; D. John Chadwick; Glenn D. Thackray; Stephen J. Dorsch

2006-01-01

280

Ultrasound Biomicroscopy for In vivo architectural characterization of gastrocnemius muscle from rats.  

PubMed

This work applies the Ultrasound Biomicroscopy (UBM) technique to quantify the pennation angle (PA) and muscle thickness (MT) of rats' gastrocnemius muscle and to determine the reliability of these measurements. UBM (40MHz) images of five Wistar female rats were acquired at two ankle positions (neutral and full extension) and in two different days. A total of 320 images were processed to quantify PA and MT and a statistical analysis assessed data variability and reliability. The coefficients of variation were 9.37 and 3.97% for PA and MT, respectively, for the ankle at full extension and 15.41 and 4.99% for the ankle at neutral position. Pearson correlation between two repeated measurements in the same image were 0.93 and 0.99 for PA and MT, respectively. The results indicate that UBM is suitable for quantitative muscle architectural characterization and can be used in future muscle biomechanical studies. PMID:21096017

Peixinho, Carolina C; Resende, Celia M C; de Oliveira, Liliam F; Machado, Joao C

2010-01-01

281

Characterization of epidermal growth factor receptors on plasma membranes isolated from rat gastric mucosa  

SciTech Connect

The binding of human epidermal growth factor (hEGF), beta-urogastrone, to plasma membranes isolated from rat gastric mucosa was studied to characterize gastric EGF receptors. The binding of ({sup 125}I)hEGF was temperature dependent, reversible, and saturable. A single class of binding sites for EGF with a dissociation constant of 0.42 nM and maximal binding capacity of 42 fmol/mg protein was suggested. There was little change in the binding of ({sup 125}I)hEGF upon addition of peptide hormones (secretin, insulin), antiulcer drugs (cimetidine), or an ulcer-inducing reagent (aspirin). Cross-linking of ({sup 125}I)hEGF to gastric plasma membranes with the use of disuccinimidyl suberate resulted in the labeling of a protein of 150 kDa. These results indicate the presence of EGF receptors on plasma membranes of rat gastric mucosa.

Hori, R.; Nomura, H.; Iwakawa, S.; Okumura, K. (Kyoto Univ. Hospital (Japan))

1990-06-01

282

Biochemical and pharmacological characterization of nuclear urotensin-II binding sites in rat heart  

PubMed Central

BACKGROUND AND PURPOSE During the past decade, a few GPCRs have been characterized at the nuclear membrane where they exert complementary physiological functions. In this study, we investigated (1) the presence of a functional urotensin-II (U-II) receptor (UT) in rat heart nuclear extracts and (2) the propensity of U-II and U-II-related peptide (URP) to cross the plasma membrane in a receptor-independent manner. EXPERIMENTAL APPROACH Biochemical and pharmacological methods including competitive binding assays, photoaffinity labelling, immunoblotting as well as de novo RNA synthesis were used to characterize the presence of functional UT receptors in rat heart nuclei. In addition, confocal microscopy and flow cytometry analysis were used to investigate the cellular uptake of fluorescent U-II and URP derivatives. KEY RESULTS The presence of specific U-II binding sites was demonstrated in rat heart nuclear extracts. Moreover, such subcellular localization was also observed in monkey heart extracts. In vitro transcription initiation assays on rat, freshly isolated, heart nuclei suggested that nuclear UT receptors are functional, and that U-II, but not URP, participates in nuclear UT-associated gene expression. Surprisingly, hU-II and URP efficiently crossed the plasma membrane in a receptor-independent mechanism involving endocytosis through caveolin-coated pits; this uptake of hU-II, but not that of URP, was dependent on extracellular pH. CONCLUSION Our results suggest that (1) U-II and URP can differentially modulate nuclear UT functions such as gene expression, and (2) both ligands can reach the internal cellular space through a receptor-independent mechanism. PMID:22044114

Doan, ND; Nguyen, TTM; Létourneau, M; Turcotte, K; Fournier, A; Chatenet, D

2012-01-01

283

Characterization of root response to phosphorus supply from morphology to gene analysis in field-grown wheat.  

PubMed

The adaptations of root morphology, physiology, and biochemistry to phosphorus supply have been characterized intensively. However, characterizing these adaptations at molecular level is largely neglected under field conditions. Here, two consecutive field experiments were carried out to investigate the agronomic traits and root traits of wheat (Triticum aestivum L.) at six P-fertilizer rates. Root samples were collected at flowering to investigate root dry weight, root length density, arbusular-mycorrhizal colonization rate, acid phosphatase activity in rhizosphere soil, and expression levels of genes encoding phosphate transporter, phosphatase, ribonucleases, and expansin. These root traits exhibited inducible, inhibitory, or combined responses to P deficiency, and the change point for responses to P supply was at or near the optimal P supply for maximum grain yield. This research improves the understanding of mechanisms of plant adaptation to soil P in intensive agriculture and provides useful information for optimizing P management based on the interactions between soil P dynamics and root processes. PMID:23382547

Teng, Wan; Deng, Yan; Chen, Xin-Ping; Xu, Xiao-Feng; Chen, Ri-Yuan; Lv, Yang; Zhao, Yan-Yan; Zhao, Xue-Qiang; He, Xue; Li, Bin; Tong, Yi-Ping; Zhang, Fu-Suo; Li, Zhen-Sheng

2013-03-01

284

Isolation, morphological and molecular characterization of phytate-hydrolysing fungi by 18S rDNA sequence analysis  

PubMed Central

Phytate is the primary storage form of phosphate in plants. Monogastric animals like poultry, pigs and fishes have very low or no phytase activities in their digestive tracts therefore, are incapable to efficiently utilize phytate phosphorus from the feed. Phytase from microbial sources are supplemented to feedstuff of these to increase the uptake of phytate phosphorus. In the present work efforts were made to isolate and characterize proficient phytase producing fungi from soil. Phytase producing fungi were isolated using phytate specific medium. Fungal isolates were selected according to their higher phytase activities. These isolates were further characterized and identified by morphological and microscopic analysis and confirmed by amplification of 18S rRNA gene, using specific primers. This gene was subsequently sequenced and phylogenetic affiliations were assigned. Fungal isolates were identified as various species of Aspergillus. Phytases from these fungi could be utilized as a feed additive in poultry and swine industries. PMID:24159322

Gontia-Mishra, Iti; Deshmukh, Dhanshree; Tripathi, Niraj; Bardiya-Bhurat, Khushboo; Tantwai, Keerti; Tiwari, Sharad

2013-01-01

285

Purification and characterization of an autoregulatory substance capable of regulating the morphological transition in Candida albicans  

PubMed Central

The yeast Candida albicans has a distinguishing feature, dimorphism, which is the ability to switch between two morphological forms: a budding yeast form and a multicellular invasive filamentous form. This ability has been postulated to contribute to the virulence of this organism. Studies on the morphological transition from a filamentous to a budding yeast form in C. albicans have shown that this organism excretes an autoregulatory substance into the culture medium. This substance was extracted and purified by normal-phase and reversed-phase HPLC. The autoregulatory substance was structurally identified as 3,7,11-trimethyl-2,6,10-dodecatrienoate (farnesoic acid) by NMR and mass spectrometry. Growth experiments suggest that this substance does not inhibit yeast cell growth but inhibits filamentous growth. These findings have implications for developmental signaling by the fungus and might have medicinal value in the development of antifungal therapies. PMID:11274356

Oh, Ki-Bong; Miyazawa, Hiroshi; Naito, Toshimichi; Matsuoka, Hideaki

2001-01-01

286

Growth and characterization of boron nitride nanotubes having novel morphologies using mechanothermal process  

Microsoft Academic Search

We report an effective approach to synthesize boron nitride (BN) nanotubes having novel morphologies employing a mechanothermal\\u000a process. In this process, a precursor containing B–N–O–Fe was first synthesized by ball milling a 1:1 mixture of elemental\\u000a boron (B) and hexagonal boron nitride (hBN) and iron oxide (about 6 wt%) for about 36 h in the presence of ammonia gas. BN\\u000a nanotubes were

Sunil Kumar Singhal; Avanish Kumar Srivastava; Nita Dilawar; Anil Kumar Gupta

2010-01-01

287

Molecular and Morphological Characterization of a Taxol-Producing Endophytic Fungus, Gliocladium sp., from Taxus baccata  

PubMed Central

The endophytic fungal populations of different tissues of Taxus baccata grown at high altitudes in West Bengal, India were explored. These isolated fungal populations represented different genera, which were screened for taxol production using immunoassay technique. The culture AAT-TS-41 that produced taxol was identified as Gliocladium sp. based on its cultural, morphological characteristics, internal transcribed spacer, and 18S rRNA sequence analysis. Kinetics of taxol production as a function of culture growth were investigated. PMID:22783096

Sushim, G. K.; Syed, A.; Khan, B. M.; Ahmad, A.

2011-01-01

288

Morphological Characterization of Viruses in the Stratified Water Column of Alkaline, Hypersaline Mono Lake  

Microsoft Academic Search

Concentrations of viruses and prokaryotes in the alkaline, moderately hypersaline, seasonally stratified Mono Lake are among\\u000a the highest reported for a natural aquatic environment. We used electron microscopy to test whether viral morphological characteristics\\u000a differed among the epilimnion, metalimnion, and the anoxic hypolimnion of the lake and to determine how the properties of\\u000a viruses in Mono Lake compare to other

Jennifer R. Brum; Grieg F. Steward

2010-01-01

289

Controlled synthesis and characterization of layered manganese oxide nanostructures with different morphologies  

Microsoft Academic Search

Layered manganese oxide nanostructures with different morphologies, such as nanowire bundles, cotton agglomerates, and platelikes\\u000a were successfully fabricated by a simple and template-free hydrothermal method based on a reaction of KMnO4 and KOH solutions with different concentrations. The obtained nanowire bundles were assembled by nanowires with diameters\\u000a of 10 to 200 nm and lengths up to 5–10 ?m. The cotton agglomerates were

Naicai Xu; Zong-Huai Liu; Xiangrong Ma; Shanfeng Qiao; Jiaqi Yuan

2009-01-01

290

Morphological characterization of ? phase in poly-(vinylidenefluoride) film prepared by spin cast method  

SciTech Connect

Poly-(Vinylidene fluoride) PVDF film was prepared by spin casting method to control the pore size of the matrix. The morphological spherulitic structure was confirmed Scanning Electron Microscopy (SEM) after gold sputtering and the presence of ? phase was ensured in spin cast PVDF film by the FTIR spectroscopy. The ? phase is very important in the application because it improve the properties like piezoelectricity by modifying PVDF crystallinity.

Mehtani, Hitesh Kumar, E-mail: kkraina@gmail.com; Kumar, Rishi, E-mail: kkraina@gmail.com; Raina, K. K., E-mail: kkraina@gmail.com [School of Physics and Materials Science, Thapar University, Patiala-147004 (India)

2014-04-24

291

Morphological characterization of cherry rootstock candidates selected from Central and East Black Sea Regions in Turkey.  

PubMed

The use of rootstocks particularly for sweet cherry cultivars is of great importance for successful and sustainable production. Choosing the right cherry rootstocks is just as important as choosing the right cultivar. In this study, 110 sweet cherry, 30 sour cherry, and 41 mahaleb types displaying rootstock potential for sweet cherry cultivars were selected from Central and East Black Sea Regions in Turkey. The morphologic characteristics of the studied genotypes were compared with the standard clonal rootstocks PHL-A, MaxMa 14, Montmorency, Weiroot 158, Gisela 5, Gisela 6, and SL 64. A total of 42 morphological UPOV characteristics were evaluated in the selected genotypes and clonal rootstocks. The obtained data were analyzed by using principal component analysis and it revealed that eigenvalues of the first 3 components were able to represent 36.43% of total variance. The most significant positive correlations of the plant vigor were determined with leaf blade length and petiole thickness. According to the diversity analysis of coefficients, the 05 C 002 and 08 C 039 genotypes were identified as being similar (6.66), while the 05 C 002 and 55 S 012 genotypes were determined as the most distant genotypes (325.84) in terms of morphology. PMID:24453921

Koc, Aysen; Celik, Zumrut; Akbulut, Mustafa; Bilgener, Sukriye; Ercisli, Sezai; Gunes, Mehmet; Gercekcioglu, Resul; Esitken, Ahmet

2013-01-01

292

Morphological Characterization of Cherry Rootstock Candidates Selected from Central and East Black Sea Regions in Turkey  

PubMed Central

The use of rootstocks particularly for sweet cherry cultivars is of great importance for successful and sustainable production. Choosing the right cherry rootstocks is just as important as choosing the right cultivar. In this study, 110 sweet cherry, 30 sour cherry, and 41 mahaleb types displaying rootstock potential for sweet cherry cultivars were selected from Central and East Black Sea Regions in Turkey. The morphologic characteristics of the studied genotypes were compared with the standard clonal rootstocks PHL-A, MaxMa 14, Montmorency, Weiroot 158, Gisela 5, Gisela 6, and SL 64. A total of 42 morphological UPOV characteristics were evaluated in the selected genotypes and clonal rootstocks. The obtained data were analyzed by using principal component analysis and it revealed that eigenvalues of the first 3 components were able to represent 36.43% of total variance. The most significant positive correlations of the plant vigor were determined with leaf blade length and petiole thickness. According to the diversity analysis of coefficients, the 05?C 002 and 08?C 039 genotypes were identified as being similar (6.66), while the 05?C 002 and 55?S 012 genotypes were determined as the most distant genotypes (325.84) in terms of morphology. PMID:24453921

Koc, Aysen; Celik, Zumrut; Akbulut, Mustafa; Bilgener, Sukriye; Ercisli, Sezai; Gunes, Mehmet; Gercekcioglu, Resul; Esitken, Ahmet

2013-01-01

293

Characterization of a new rat model for chronic inflammatory demyelinating polyneuropathies.  

PubMed

Our objective was to develop a chronic model of EAN which could be used as a tool to test treatment strategies for CIDP. Lewis rats injected with S-palmitoylated P0(180-199) peptide developed a chronic, sometimes relapsing-remitting type of disease. Our model fulfills electrophysiological criteria of demyelination with axonal degeneration, confirmed by immunohistopathology. The late phase of the chronic disease was characterized by accumulation of IL-17(+) cells and macrophages in sciatic nerves and by high serum IL-17 levels. In conclusion, we have developed a reliable and reproducible animal model resembling CIDP that can now be used for translational drug studies. PMID:25595246

Brun, Susana; Beaino, Wissam; Kremer, Laurent; Taleb, Omar; Mensah-Nyagan, Ayikoe Guy; Lam, Chanh D; Greer, Judith M; de Seze, Jérôme; Trifilieff, Elisabeth

2015-01-15

294

Experimental intracerebral hematoma in the rat: Characterization by sequential magnetic resonance imaging, behavior, and histopathology. Effect of albumin therapy  

Microsoft Academic Search

We characterized acute intracerebral hemorrhage (ICH) in the rat by sequential magnetic resonance imaging (MRI) and correlated MRI findings with neurobehavior and histopathology. In addition, we investigated whether albumin treatment would reduce ICH-induced brain injury. ICH was produced in rats by a double-injection method in which 45 ?l of fresh arterial blood was injected into the right striatum. Susceptibility-weighted (SWI) and

Ludmila Belayev; Andre Obenaus; Weizhao Zhao; Isabel Saul; Raul Busto; Chunyan Wu; Alexey Vigdorchik; Baowan Lin; Myron D. Ginsberg

2007-01-01

295

Characterization of the Bone Loss and Recovery Response at the Distal Femur Metaphysis of the Adult Male Hindlimb Unloaded Rat  

E-print Network

CHARACTERIZATION OF THE BONE LOSS AND RECOVERY RESPONSE AT THE DISTAL FEMUR METAPHYSIS OF THE ADULT MALE HINDLIMB UNLOADED RAT A Thesis by JOSHUA MORGAN DAVIS Submitted to the Office of Graduate Studies of Texas A... OF THE ADULT MALE HINDLIMB UNLOADED RAT A Thesis by JOSHUA MORGAN DAVIS Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Approved by: Co...

Davis, Joshua Morgan

2012-02-14

296

Characterizing the morphology of gully cross-sections based on PCA: A case of Yuanmou Dry-Hot Valley  

NASA Astrophysics Data System (ADS)

A cross-section of a gully (GC) is important not only for computing the volume and rate of erosion of the gully but also for understanding the relationship of the gullying process, landforms, land use and erosional features. To effectively characterize the accurate morphology of GCs and to explain their statistical regularity, this study proposes 26 morphological parameters for describing the cross-sections of permanent gullies. We surveyed 456 GCs with a laser distance meter located at the mouth, middle and head of 152 gullies in the Yuanmou Dry-Hot Valley of China, mapped them with CASS software, and calculated the morphologic parameters. Based on principal component analysis (PCA), the morphological characteristics can be notably expressed by four principal components and fewer parameters with heavier load information. The first principal component (PC) reflected the dimensions of GCs, with the key parameters of width, depth, and area of the cross-section. Over 94% of the depth of the left side (dl), the top width (wt) and the area (s) were in the range of 0-12 m, 3-27 m, and 0-200 m2, respectively. The second PC indicated the degree of the gully's asymmetry in terms of the parameter of asymmetry ratio of width. There are 201 GCs of right-deflection and 184 of left-deflection. The third PC expressed the degree of erosion in terms of erosiveness and shape. There are 77 V-shaped, 25 U-shaped, and 354 intermediate shaped gullies. The percentage of U-shaped cross-sections is noticeably higher at the gully head than at the gully mouth and middle. The fourth PC reflects the erosional pattern difference. The value of the width/depth ratio was distributed and varied greatly within the range of 0.92-10.69 with an average value of 3.33. These key parameters differed at different locations and sites. The shape of GCs differs at different stages of development. Weathering crusts, soil properties, and vegetation cover are important for controlling the morphology of GCs in the Yuanmou Dry-Hot Valley. This study will not only help to improve the content of gully morphology, but will also contribute to understanding the controlling factors and evolution mechanism of gullies.

Deng, Qingchun; Qin, Fachao; Zhang, Bin; Wang, Haipeng; Luo, Mingliang; Shu, Chengqiang; Liu, Hui; Liu, Gangcai

2015-01-01

297

Thermally sensitive block copolymer particles prepared via aerosol flow reactor method: Morphological characterization and behavior in water  

PubMed Central

This work describes properties of thermo-sensitive submicron sized particles having the same chemical composition but different morphologies. These particles have been prepared with an aerosol technique using dimethylformamide solutions of linear polystyrene-block-poly(N-isopropylacrylamide-block-polystyrene, PS-b-PNIPAM-b-PS. The particles were characterized by cryo-electron microscopy, microcalorimetry, and light scattering. Block-copolymers self-assembled within the particles forming onion-like, gyroid-like, and spherical morphologies having poly(N-isopropylacrylamide) matrix and physically cross-linking polystyrene domains. The particles were dispersed in aqueous media and their behavior in water was studied both below and above the lower critical solution temperature of poly(N-isopropylacrylamide). We found out that the particles with spherical and gyroid-like morphologies swell considerably in water at 20 °C, whereas at 40 °C the particles resemble more of those studied without water treatment. Light scattering experiments showed that the particles gradually aggregate and precipitate with time at 40 °C. Microcalorimetric studies revealed for all three studied morphologies that PNIPAM undergoes a two-step transition due to the different hydration levels of PNIPAM inside and outside the particles. Thicknesses of the PS and PNIPAM layers within the onion-like particles were analyzed using the TEM micrographs by fitting a model of electron density to the integrated electron intensity data. The surface layer of the particles was found out to be PNIPAM, which was supported by light scattering and microcalorimetry. It was also found out from the TEM micrograph analysis that the width of the outmost PS layer is considerably thinner than the one in the dry state prior to immersion in water, and a degradation scheme is proposed to explain these results. PMID:23150721

Nykänen, Antti; Rahikkala, Antti; Hirvonen, Sami-Pekka; Aseyev, Vladimir; Tenhu, Heikki; Mezzenga, Raffaele; Raula, Janne; Kauppinen, Esko; Ruokolainen, Janne

2012-01-01

298

Thermally sensitive block copolymer particles prepared via aerosol flow reactor method: Morphological characterization and behavior in water.  

PubMed

This work describes properties of thermo-sensitive submicron sized particles having the same chemical composition but different morphologies. These particles have been prepared with an aerosol technique using dimethylformamide solutions of linear polystyrene-block-poly(N-isopropylacrylamide-block-polystyrene, PS-b-PNIPAM-b-PS. The particles were characterized by cryo-electron microscopy, microcalorimetry, and light scattering. Block-copolymers self-assembled within the particles forming onion-like, gyroid-like, and spherical morphologies having poly(N-isopropylacrylamide) matrix and physically cross-linking polystyrene domains. The particles were dispersed in aqueous media and their behavior in water was studied both below and above the lower critical solution temperature of poly(N-isopropylacrylamide). We found out that the particles with spherical and gyroid-like morphologies swell considerably in water at 20 °C, whereas at 40 °C the particles resemble more of those studied without water treatment. Light scattering experiments showed that the particles gradually aggregate and precipitate with time at 40 °C. Microcalorimetric studies revealed for all three studied morphologies that PNIPAM undergoes a two-step transition due to the different hydration levels of PNIPAM inside and outside the particles. Thicknesses of the PS and PNIPAM layers within the onion-like particles were analyzed using the TEM micrographs by fitting a model of electron density to the integrated electron intensity data. The surface layer of the particles was found out to be PNIPAM, which was supported by light scattering and microcalorimetry. It was also found out from the TEM micrograph analysis that the width of the outmost PS layer is considerably thinner than the one in the dry state prior to immersion in water, and a degradation scheme is proposed to explain these results. PMID:23150721

Nykänen, Antti; Rahikkala, Antti; Hirvonen, Sami-Pekka; Aseyev, Vladimir; Tenhu, Heikki; Mezzenga, Raffaele; Raula, Janne; Kauppinen, Esko; Ruokolainen, Janne

2012-10-23

299

Morphological and molecular characterization of Fusarium. solani and F. oxysporum associated with crown disease of oil palm  

PubMed Central

Crown disease (CD) is infecting oil palm in the early stages of the crop development. Previous studies showed that Fusarium species were commonly associated with CD. However, the identity of the species has not been resolved. This study was carried out to identify and characterize through morphological approaches and to determine the genetic diversity of the Fusarium species. 51 isolates (39%) of Fusarium solani and 40 isolates (31%) of Fusarium oxysporum were recovered from oil palm with typical CD symptoms collected from nine states in Malaysia, together with samples from Padang and Medan, Indonesia. Based on morphological characteristics, isolates in both Fusarium species were classified into two distinct morphotypes; Morphotypes I and II. Molecular characterization based on IGS-RFLP analysis produced 27 haplotypes among the F. solani isolates and 33 haplotypes for F. oxysporum isolates, which indicated high levels of intraspecific variations. From UPGMA cluster analysis, the isolates in both Fusarium species were divided into two main clusters with the percentage of similarity from 87% to 100% for F. solani, and 89% to 100% for F. oxysporum isolates, which was in accordance with the Morphotypes I and II. The results of the present study indicated that F. solani and F. oxysporum associated with CD of oil palm in Malaysia and Indonesia were highly variable. PMID:24516465

Hafizi, R.; Salleh, B.; Latiffah, Z.

2013-01-01

300

Hormonal regulation of rat Leydig cell cytochrome P-45017 alpha mRNA levels and characterization of a partial length rat P-45017 alpha cDNA.  

PubMed

We have isolated and characterized a P-45017 alpha cDNA fragment from a rat testis library. The partial length rat P-45017 alpha cDNA (1Kb) has high overall nucleotide and deduced amino acid similarity with human and bovine P-45017 alpha cDNA's and contains the conserved tridecapeptide and heme regions, the termination codon and polyadenylation site. Using this rat testis cDNA probe we measured P-45017 alpha mRNA levels of rat Leydig cells from animals treated with hCG. Temporal studies with a low hCG dose showed an early increase in mRNA levels returning to control values at later times, while a higher desensitizing dose caused a marked reduction in the mRNA (24 h) and a small recovery at 48 h. Fetal rat Leydig cells maintained in the presence of LH treated with estradiol showed a 70% decrease in P-45017 alpha mRNA levels and testosterone production followed closely the changes in P-45017 alpha mRNA. These studies suggest that gonadotropin stimulation and desensitization of P-45017 alpha dependent enzymes in the adult rat testis as well as estradiol induced desensitization in fetal Leydig cells are related to levels P-45017 alpha mRNA. PMID:3260774

Nishihara, M; Winters, C A; Buzko, E; Waterman, M R; Dufau, M L

1988-07-15

301

Characterization of Gicerin/MUC18/CD146 in the rat nervous system.  

PubMed

Gicerin is a cell adhesion molecule of an immunoglobulin (Ig) superfamily isolated from a chicken. It shows homophilic and heterophilic binding activities and has two isoforms. s-Gicerin which has small cytoplasmic domain and the same extracellular domain as l-gicerin shows stronger cell adhesion activity. In the chick nervous system, gicerin expression is only observed in the developmental stage when neurons extend neurites and migrate. In other tissues, gicerin participates in the tissue regeneration or oncogenesis. In this report, we identified two isoforms of rat gicerin corresponding to chicken and we concluded that gicerin is a homologue of human CD146/MUC18/MCAM. Next we generated antibody to characterize a rat gicerin in the nervous system. Gicerin is expressed in the hippocampal cells, Purkinje cells, and sensory neurons of a spinal chord of an adult rat, while expressed most abundantly in the lung. In addition to this, its expression in the hippocampus was increased by electroconvulsive shock, suggesting some role in the mature nervous system. And we also showed neurite promotion activity of gicerin from hippocampal neurons. PMID:14755543

Taira, Eiichi; Kohama, Keiko; Tsukamoto, Yasuhiro; Okumura, Shigeki; Miki, Naomasa

2004-03-01

302

Cloning and characterization of the rat homologues of the Inhibitor of Apoptosis protein 1, 2, and 3 genes.  

PubMed Central

Background Inhibitor of Apoptosis (IAP) proteins are key intrinsic regulators of apoptosis induced by a variety of triggers. We isolated the rat Inhibitor of Apoptosis genes 1, 2 and 3 and characterized their tissue distribution and expression. Results Rat iap-1 encodes a protein of 67.1 kDa with 73 % and 89.2 % homology to human and mouse iap-1 respectively. Rat iap-2 encodes a protein of 66.7 kDa with 81.6 % and 89.3 % homology to human and mouse iap-2 respectively. Rat iap-3 encodes a protein of 56.1 kDa with 89.5 % and 93.1 % homology to human and mouse iap-3 respectively. We have generated rabbit polyclonal antibodies against all three rat IAP genes. Northern and Western blot analysis detected rat IAP transcripts and proteins in majority of the tissues examined. In addition, a shorter, alternatively spliced transcript corresponding to iap-2 was found in testes. Conclusions We have identified three rat homologues of the IAP genes. The elevated expression of rat iap-1 and iap2 in testes suggests that these two genes play an important antiapoptotic role in spermatogenesis. PMID:11860601

Holcik, Martin; Lefebvre, Charles A; Hicks, Keiko; Korneluk, Robert G

2002-01-01

303

Mechanical, thermal and morphological characterization of recycled LDPE\\/corn starch blends  

Microsoft Academic Search

Recycled LDPE\\/corn starch blends containing 30, 40 and 50wt% starch were prepared by extrusion and characterized by the melt flow index (MFI), tensile test, dynamic mechanical thermal analysis (DMTA) and scanning electron microscopy (SEM). For comparison, virgin LDPE\\/corn starch blends were prepared and characterized under the same conditions. The addition of starch to LDPE reduced the MFI values, the tensile

A. G. Pedroso; D. S. Rosa

2005-01-01

304

IN UTERO 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD) ALTERSREPRODUCTIVE MORPHOLOGY AND FUNCTION IN FEMALE RAT OFFSPRING  

EPA Science Inventory

Recently, it was demonstrated that administration of TCDD during gestation permanently alters 'the reproductive potential of male rat and male hamster offspring. he objectives of this study were to determine if perinatal TCDD treatment altered sex differentiation and reproductive...

305

Morphological characterization of the nasopalatine region in human fetuses and its association to pathologies  

PubMed Central

The nasopalatine region is composed of structures such as the vomeronasal organ and nasopalatine duct. The nasopalatine duct may provide the communication of the mouth to the nasal cavity in human fetuses and can be obliterated in an adult human. Knowledge on the development of the nasopalatine region and nasopalatine duct in humans is necessary for understanding the morphology and etiopathogenesis of lesions that occur in this region. Objective: The aim of the present study was to describe the morphological aspects of the nasopalatine region in human fetuses and correlate these aspects with the development of pathologies in this region. Material and Methods: Five human fetuses with no facial or palatine abnormalities were used for the acquisition of specimens from the nasopalatine region. After demineralization, the specimens were histologically processed. Histological cuts were stained with methylene blue to orient the cutting plane and hematoxylin-eosin for the descriptive histological analysis. Results: The age of the fetuses was 8.00, 8.25, 9.00 and 9.25 weeks, and it was not possible to determine the age in the last one. The incisive canal was observed in all specimens as an opening delimited laterally by the periosteum and connecting oral and nasal cavity. The nasopalatine duct is an epithelial structure with the greatest morphological variation, with either unilateral or bilateral occurrence and total patent, partial patent and islet forms. The vomeronasal organ is a bilateral epithelized structure located alongside the nasal septum above the incisive canal in all the fetuses. Conclusions: The incisive canal, nasopalatine duct and vomeronasal organ are distinct anatomic structures. The development of nasopalatine duct cysts may occur in all forms of the nasopalatine duct. PMID:23857659

FALCI, Saulo Gabriel Moreira; VERLI, Flaviana Dornela; CONSOLARO, Alberto; dos SANTOS, Cássio Roberto Rocha

2013-01-01

306

Characterization of two ENU-induced mutations affecting mouse skeletal morphology.  

PubMed

Using the N-ethyl-N-nitrosourea (ENU) mutagenesis screen, we have identified two skeletal morphology mutants, Skm1 and Skm2. Positional cloning and candidate gene sequencing localized the causative point mutations within the genes coding for natriuretic peptide receptor C (NPR-C) and filamin b (FLNB), respectively. Mice that carry a mutation in Npr3 exhibit a skeletal overgrowth phenotype, resulting in an elongated body and kyphosis. Skm2 mice, carrying a mutation in Flnb, present with scoliosis and lordosis. These mutant mice will serve as useful models for the study of vertebral malformations. PMID:23979929

Dauphinee, Shauna M; Eva, Megan M; Yuki, Kyoko E; Herman, Melissa; Vidal, Silvia M; Malo, Danielle

2013-10-01

307

Characterization of a Shaw-related potassium channel family in rat brain.  

PubMed

Previously, we characterized a Shaker-related family of voltage-gated potassium channels (RCK) in rat brain. Now, we describe a second family of voltage-gated potassium channels in the rat nervous system. This family is related to the Drosophila Shaw gene and has been dubbed Raw. In contrast to the RCK potassium channel family the Raw family utilizes extensive alternative splicing for expressing potassium channel subunits with variant C-termini. These alternative C-termini do not appear to influence the electrophysiological and pharmacological properties as studied in the Xenopus oocyte expression system. In situ hybridizations to sections of rat brain indicate that members of the Raw family are expressed in distinct areas of the central nervous system. Probably, Raw channels are expressed predominantly as homomultimers. Immunocytochemical experiments with antibodies against Raw3 and RCK4 proteins which form two distinct A-type potassium channels indicate that in hippocampus the two channels are expressed both in different neurons and in the same ones. In general, properties of Raw potassium channels appeared to be similar to RCK channels. However, Raw outward currents, in contrast to RCK currents, exhibit an intense rectification at test potentials higher than +20 to +40 mV. RCK and Raw channel subunits did not measurably coassemble into RCK/Raw heteromultimers after coinjecting RCK and Raw cRNA into Xenopus oocytes. These results suggest that members of the RCK and the Raw potassium channel families express potassium channels which form independent outward current systems. Combining the results of in situ hybridizations, immunocytochemical staining and expression of the cloned potassium channels in Xenopus oocytes demonstrates that unrestrained mixing of potassium channel subunits to form hybrid channels does not occur in the rat central nervous system. A single neuron is able to express multiple, independently assembled potassium channels. PMID:1378392

Rettig, J; Wunder, F; Stocker, M; Lichtinghagen, R; Mastiaux, F; Beckh, S; Kues, W; Pedarzani, P; Schröter, K H; Ruppersberg, J P

1992-07-01

308

Characterization of a Shaw-related potassium channel family in rat brain.  

PubMed Central

Previously, we characterized a Shaker-related family of voltage-gated potassium channels (RCK) in rat brain. Now, we describe a second family of voltage-gated potassium channels in the rat nervous system. This family is related to the Drosophila Shaw gene and has been dubbed Raw. In contrast to the RCK potassium channel family the Raw family utilizes extensive alternative splicing for expressing potassium channel subunits with variant C-termini. These alternative C-termini do not appear to influence the electrophysiological and pharmacological properties as studied in the Xenopus oocyte expression system. In situ hybridizations to sections of rat brain indicate that members of the Raw family are expressed in distinct areas of the central nervous system. Probably, Raw channels are expressed predominantly as homomultimers. Immunocytochemical experiments with antibodies against Raw3 and RCK4 proteins which form two distinct A-type potassium channels indicate that in hippocampus the two channels are expressed both in different neurons and in the same ones. In general, properties of Raw potassium channels appeared to be similar to RCK channels. However, Raw outward currents, in contrast to RCK currents, exhibit an intense rectification at test potentials higher than +20 to +40 mV. RCK and Raw channel subunits did not measurably coassemble into RCK/Raw heteromultimers after coinjecting RCK and Raw cRNA into Xenopus oocytes. These results suggest that members of the RCK and the Raw potassium channel families express potassium channels which form independent outward current systems. Combining the results of in situ hybridizations, immunocytochemical staining and expression of the cloned potassium channels in Xenopus oocytes demonstrates that unrestrained mixing of potassium channel subunits to form hybrid channels does not occur in the rat central nervous system. A single neuron is able to express multiple, independently assembled potassium channels. Images PMID:1378392

Rettig, J; Wunder, F; Stocker, M; Lichtinghagen, R; Mastiaux, F; Beckh, S; Kues, W; Pedarzani, P; Schröter, K H; Ruppersberg, J P

1992-01-01

309

Purification and characterization of a luminal cholecystokinin-releasing factor from rat intestinal secretion.  

PubMed Central

Cholecystokinin (CCK) secretion in rats and humans is inhibited by pancreatic proteases and bile acids in the intestine. It has been hypothesized that the inhibition of CCK release caused by pancreatic proteases is due to proteolytic inactivation of a CCK-releasing peptide present in intestinal secretion. To purify the putative luminal CCK-releasing factor (LCRF), intestinal secretions were collected by perfusing a modified Thiry-Vella fistula of jejunum in conscious rats. From these secretions, the peptide was concentrated by ultrafiltration followed by low-pressure reverse-phase chromatography and purified by reverse-phase high-pressure liquid chromatography. Purity was confirmed by high-performance capillary electrophoresis. Fractions were assayed for CCK-releasing activity by their ability to stimulate pancreatic protein secretion when infused into the proximal small intestine of conscious rats. Partially purified fractions strongly stimulated both pancreatic secretion and CCK release while CCK receptor blockade abolished the pancreatic response. Amino acid analysis and mass spectral analysis showed that the purified peptide is composed of 70-75 amino acid residues and has a mass of 8136 Da. Microsequence analysis of LCRF yielded an amino acid sequence for 41 residues as follows: STFWAYQPDGDNDPTDYQKYEHTSSPSQLLAPGDYPCVIEV. When infused intraduodenally, the purified peptide stimulated pancreatic protein and fluid secretion in a dose-related manner in conscious rats and significantly elevated plasma CCK levels. Immunoaffinity chromatography using antisera raised to synthetic LCRF-(1-6) abolished the CCK releasing activity of intestinal secretions. These studies demonstrate, to our knowledge, the first chemical characterization of a luminally secreted enteric peptide functioning as an intraluminal regulator of intestinal hormone release. PMID:8633081

Spannagel, A W; Green, G M; Guan, D; Liddle, R A; Faull, K; Reeve, J R

1996-01-01

310

Purification and characterization of a luminal cholecystokinin-releasing factor from rat intestinal secretion.  

PubMed

Cholecystokinin (CCK) secretion in rats and humans is inhibited by pancreatic proteases and bile acids in the intestine. It has been hypothesized that the inhibition of CCK release caused by pancreatic proteases is due to proteolytic inactivation of a CCK-releasing peptide present in intestinal secretion. To purify the putative luminal CCK-releasing factor (LCRF), intestinal secretions were collected by perfusing a modified Thiry-Vella fistula of jejunum in conscious rats. From these secretions, the peptide was concentrated by ultrafiltration followed by low-pressure reverse-phase chromatography and purified by reverse-phase high-pressure liquid chromatography. Purity was confirmed by high-performance capillary electrophoresis. Fractions were assayed for CCK-releasing activity by their ability to stimulate pancreatic protein secretion when infused into the proximal small intestine of conscious rats. Partially purified fractions strongly stimulated both pancreatic secretion and CCK release while CCK receptor blockade abolished the pancreatic response. Amino acid analysis and mass spectral analysis showed that the purified peptide is composed of 70-75 amino acid residues and has a mass of 8136 Da. Microsequence analysis of LCRF yielded an amino acid sequence for 41 residues as follows: STFWAYQPDGDNDPTDYQKYEHTSSPSQLLAPGDYPCVIEV. When infused intraduodenally, the purified peptide stimulated pancreatic protein and fluid secretion in a dose-related manner in conscious rats and significantly elevated plasma CCK levels. Immunoaffinity chromatography using antisera raised to synthetic LCRF-(1-6) abolished the CCK releasing activity of intestinal secretions. These studies demonstrate, to our knowledge, the first chemical characterization of a luminally secreted enteric peptide functioning as an intraluminal regulator of intestinal hormone release. PMID:8633081

Spannagel, A W; Green, G M; Guan, D; Liddle, R A; Faull, K; Reeve, J R

1996-04-30

311

Characterization of corpus cavernosum smooth muscle cell phenotype in diabetic rats with erectile dysfunction.  

PubMed

Phenotypic modulation from a contractile to a proliferative state within vascular smooth muscle cells has a critical role in the pathogenesis of a variety of cardiovascular diseases. To investigate the characterization of corpus cavernosum smooth muscle cell phenotype in diabetic rats with erectile dysfunction, a group of Sprague-Dawley rats (n=30) were induced by intraperitoneal injection of streptozotocin (60?mg?kg(-1)) and screened by subcutaneous injection of apomorphine (100??g?kg(-1)) for the measurement and comparison of the penile erections, and then three different groups were defined. Primary corpus cavernosum smooth muscle cells were cultured and passaged. The cavernous tissue segments were subjected to quantitative real-time polymerase chain reaction to determine the expressions of smooth muscle ?-actin (SMA), SM myosin heavy chain (SMMHC), smoothelin, calponin and myocardin. Cell contractility in vitro and western blot analysis of SMA and SMMHC in the cavernous tissues and cells were determined. Compared with the control group (n=8) and the diabetes mellitus group (n=5), the expressions of SMA, calponin, SMMHC, smoothelin and myocardin mRNA were decreased in the cavernous tissues in rats of the diabetic erectile dysfunction group (n=15; P=0.001 and 0.02, P=0.014 and 0.012, both P<0.001, P=0.005 and <0.001, P=0.003 and 0.035, respectively). The levels of SMA and SMMHC proteins showed a significant decrease in cavernous tissues and cultured cells in rats of the diabetic erectile dysfunction group. Cells of the diabetic erectile dysfunction group exhibited significantly less contractility compared with those of other groups (P<0.001). Corpus cavernosum SM cell possesses the ability to modulate the phenotype under hyperglycemic conditions, which could have a key role in the pathogenesis of diabetic erectile dysfunction. PMID:22592762

Wei, A-Y; He, S-H; Zhao, J-F; liu, Y; Liu, Y; Hu, Y-W; Zhang, T; Wu, Z-Y

2012-09-01

312

Impact of Thoracic Surgery on Cardiac Morphology and Function in Small Animal Models of Heart Disease: A Cardiac MRI Study in Rats  

PubMed Central

Background Surgical procedures in small animal models of heart disease might evoke alterations in cardiac morphology and function. The aim of this study was to reveal and quantify such potential artificial early or long term effects in vivo, which might account for a significant bias in basic cardiovascular research, and, therefore, could potentially question the meaning of respective studies. Methods Female Wistar rats (n?=?6 per group) were matched for weight and assorted for sham left coronary artery ligation or control. Cardiac morphology and function was then investigated in vivo by cine magnetic resonance imaging at 7 Tesla 1 and 8 weeks after the surgical procedure. The time course of metabolic and inflammatory blood parameters was determined in addition. Results Compared to healthy controls, rats after sham surgery showed a lower body weight both 1 week (267.5±10.6 vs. 317.0±11.3 g, n<0.05) and 8 weeks (317.0±21.1 vs. 358.7±22.4 g, n<0.05) after the intervention. Left and right ventricular morphology and function were not different in absolute measures in both groups 1 week after surgery. However, there was a confined difference in several cardiac parameters normalized to the body weight (bw), such as myocardial mass (2.19±0.30/0.83±0.13 vs. 1.85±0.22/0.70±0.07 mg left/right per g bw, p<0.05), or enddiastolic ventricular volume (1.31±0.36/1.21±0.31 vs. 1.14±0.20/1.07±0.17 µl left/right per g bw, p<0.05). Vice versa, after 8 weeks, cardiac masses, volumes, and output showed a trend for lower values in sham operated rats compared to controls in absolute measures (782.2±57.2/260.2±33.2 vs. 805.9±84.8/310.4±48.5 mg, p<0.05 for left/right ventricular mass), but not normalized to body weight. Matching these findings, blood testing revealed only minor inflammatory but prolonged metabolic changes after surgery not related to cardiac disease. Conclusion Cardio-thoracic surgical procedures in experimental myocardial infarction cause distinct alterations upon the global integrity of the organism, which in the long term also induce circumscribed repercussions on cardiac morphology and function. This impact has to be considered when analyzing data from respective animal studies and transferring these findings to conditions in patients. PMID:23990872

Nordbeck, Peter; Bönhof, Leoni; Hiller, Karl-Heinz; Voll, Sabine; Arias-Loza, Paula; Seidlmayer, Lea; Williams, Tatjana; Ye, Yu-Xiang; Gensler, Daniel; Pelzer, Theo; Ertl, Georg; Jakob, Peter M.

2013-01-01

313

A dual-modality optical coherence tomography and fluorescence lifetime imaging microscopy system for simultaneous morphological and biochemical tissue characterization  

PubMed Central

Most pathological conditions elicit changes in the tissue optical response that may be interrogated by one or more optical imaging modalities. Any single modality typically only furnishes an incomplete picture of the tissue optical response, hence an approach that integrates complementary optical imaging modalities is needed for a more comprehensive non-destructive and minimally-invasive tissue characterization. We have developed a dual-modality system, incorporating optical coherence tomography (OCT) and fluorescence lifetime imaging microscopy (FLIM), that is capable of simultaneously characterizing the 3-D tissue morphology and its biochemical composition. The Fourier domain OCT subsystem, at an 830 nm center wavelength, provided high-resolution morphological volumetric tissue images with an axial and lateral resolution of 7.3 and 13.4 µm, respectively. The multispectral FLIM subsystem, based on a direct pulse-recording approach (upon 355 nm laser excitation), provided two-dimensional superficial maps of the tissue autofluorescence intensity and lifetime at three customizable emission bands with 100 µm lateral resolution. Both subsystems share the same excitation/illumination optical path and are simultaneously raster scanned on the sample to generate coregistered OCT volumes and FLIM images. The developed OCT/FLIM system was capable of a maximum A-line rate of 59 KHz for OCT and a pixel rate of up to 30 KHz for FLIM. The dual-modality system was validated with standard fluorophore solutions and subsequently applied to the characterization of two biological tissue types: postmortem human coronary atherosclerotic plaques, and in vivo normal and cancerous hamster cheek pouch epithelial tissue. PMID:21258457

Park, Jesung; Jo, Javier A.; Shrestha, Sebina; Pande, Paritosh; Wan, Qiujie; Applegate, Brian E.

2010-01-01

314

Characterization of flexible ECoG electrode arrays for chronic recording in awake rats  

PubMed Central

We developed a 64 channel flexible polyimide ECoG electrode array and characterized its performance for long term implantation, chronic cortical recording and high resolution mapping of surface evoked potentials in awake rats. To achieve the longest possible recording periods, the flexibility of the electrode array, adhesion between the metals and carrier substrate, and biocompatibility was critical for maintaining the signal integrity. Experimental testing of thin film adhesion was applied to a gold – polyimide system in order to characterize relative interfacial fracture energies for several different adhesion layers, yielding an increase in overall device reliability. We tested several different adhesion techniques including: gold alone without an adhesion layer, titanium-tungsten, tantalum and chromium. We found the titanium-tungsten to be a suitable adhesion layer considering the biocompatibility requirements as well as stability and delamination resistance. While chromium and tantalum produced stronger gold adhesion, concerns over biocompatibility of these materials require further testing. We implanted the polyimide ECoG electrode arrays through a slit made in the skull of rats and recorded cortical surface evoked responses. The arrays performed reliably over a period of at least 100 days and signals compared well with traditional screw electrodes, with better high frequency response characteristics. Since the ultimate goal of chronically implanted electrode arrays is for neural prosthetic devices that need to last many decades, other adhesion layers that would prove safe for implantation may be tested in the same way in order to improve the device reliability. PMID:18640155

Yeager, John D.; Phillips, Derrick J.; Rector, David M.; Bahr, David F.

2008-01-01

315

Morphological Characterization and Assessment of Genetic Variability, Character Association, and Divergence in Soybean Mutants  

PubMed Central

Genetic diversity is important for crop improvement. An experiment was conducted during 2011 to study genetic variability, character association, and genetic diversity among 27 soybean mutants and four mother genotypes. Analysis of variance revealed significant differences among the mutants and mothers for nine morphological traits. Eighteen mutants performed superiorly to their mothers in respect to seed yield and some morphological traits including yield attributes. Narrow differences between phenotypic and genotypic coefficients of variation (PCV and GCV) for most of the characters revealed less environmental influence on their expression. High values of heritability and genetic advance with high GCV for branch number, plant height, pod number, and seed weight can be considered as favorable attributes for soybean improvement through phenotypic selection and high expected genetic gain can be achieved. Pod and seed number and maturity period appeared to be the first order traits for higher yield and priority should be given in selection due to their strong associations and high magnitudes of direct effects on yield. Cluster analysis grouped 31 genotypes into five groups at the coefficient value of 235. The mutants/genotypes from cluster I and cluster II could be used for hybridization program with the mutants of clusters IV and V in order to develop high yielding mutant-derived soybean varieties for further improvement. PMID:25197722

Malek, M. A.; Rafii, Mohd Y.; Shahida Sharmin Afroz, Most.; Nath, Ujjal Kumar; Mondal, M. Monjurul Alam

2014-01-01

316

Morphological and electrochemical characterization of electrodeposited Zn–Ag nanoparticle composite coatings  

SciTech Connect

Silver nanoparticles with an average size of 23 nm were chemically synthesized and used to fabricate Zn–Ag composite coatings. The Zn–Ag composite coatings were generated by electrodeposition method using a simple sulfate plating bath dispersed with 0.5, 1 and 1.5 g/l of Ag nanoparticles. Scanning electron microscopy, X-ray diffraction and texture co-efficient calculations revealed that Ag nanoparticles appreciably influenced the morphology, micro-structure and texture of the deposit. It was also noticed that agglomerates of Ag nanoparticles, in the case of high bath load conditions, produced defects and dislocations on the deposit surface. Ag nanoparticles altered the corrosion resistance property of Zn–Ag composite coatings as observed from Tafel polarization, electrochemical impedance analysis and an immersion test. Reduction in corrosion rate with increased charge transfer resistance was observed for Zn–Ag composite coatings when compared to a pure Zn coating. However, the particle concentration in the plating bath and their agglomeration state directly influenced the surface morphology and the subsequent corrosion behavior of the deposits. - Highlights: • Synthesis of Ag nanoparticles with an average size of 23 nm • Fabrication of Zn/nano Ag composite coating on mild steel • Composite coatings showed better corrosion resistance. • Optimization of particle concentration is necessary.

Punith Kumar, M.K.; Srivastava, Chandan, E-mail: csrivastava@materials.iisc.ernet.in

2013-11-15

317

Synthesis and characterization of silver nanowires with zigzag morphology in N,N-dimethylformamide  

SciTech Connect

Zigzag silver nanowires with a uniform diameter of 20{+-}5 nm were prepared by reducing silver nitrate (AgNO{sub 3}) with N,N-dimethylformamide (DMF) in the presence of tetrabutyl titanate (TBT) and acetylacetone (AcAc) at 373 K for 18 h. X-ray and selected area electron diffraction (XRD and SAED) patterns reveal that the prepared product is made of pure silver with face centered cubic structure. Transmission electron microscopy (TEM) investigations suggest that the amount of silver nanowires is enhanced with increase in reaction time, and the end-to-end assemblies of silver nanorods are observed during the reaction process. After 18 h reaction, silver nanowires with zigzag morphology are obtained. In this paper, a possible growth process of silver nanowires with this interesting shape is described. Silver nanoparticles with small sizes were obtained by reducing Ag{sup +} ions with DMF, providing seeds for homogeneous growth of silver nanorods. With the extending reaction time, the synthesized silver nanorods were connected in an end-to-end manner, and the interface between the connections of two nanorods gradually disappeared. The final product shows zigzag morphology with various angles. The angles between two connecting straight parts of zigzag nanowires exhibit an alterable range of 74-151{sup o}. These silver nanowires show tremendous potential applications in future nanoscale electronic circuits. - Graphical abstract: The evolution process of zigzag silver nanowires developed from the end-to-end assemblies of silver nanorods.

He Xin [Key Laboratory of Silicate Materials Science and Engineering, Wuhan University of Technology, Ministry of Education, 122 Luoshi Road, Hongshan District, Wuhan, Hubei 430070 (China)], E-mail: hexin1981@126.com; Zhao Xiujian [Key Laboratory of Silicate Materials Science and Engineering, Wuhan University of Technology, Ministry of Education, 122 Luoshi Road, Hongshan District, Wuhan, Hubei 430070 (China)], E-mail: zhaoxj@public.wh.hb.cn; Chen Yunxia; Feng Jinyang [Key Laboratory of Silicate Materials Science and Engineering, Wuhan University of Technology, Ministry of Education, 122 Luoshi Road, Hongshan District, Wuhan, Hubei 430070 (China); Sun Zhenya [Center for Materials Research and Testing, Wuhan University of Technology, 122 Luoshi Road, Hongshan District, Wuhan, Hubei 430070 (China)

2007-08-15

318

Morphological and Physiological Characterization of Listeria monocytogenes Subjected to High Hydrostatic Pressure  

PubMed Central

High hydrostatic pressure is a new food preservation technology known for its capacity to inactivate spoilage and pathogenic microorganisms. That inactivation is usually assessed by the number of colonies growing on solid media after treatment. Under normal conditions the method does not permit recovery of damaged cells and may underestimate the number of cells that will remain viable and grow after a few days in high-pressure-processed foodstuffs. This study investigated the damage inflicted on Listeria monocytogenes cells treated by high pressure for 10 min at 400 MPa in pH 5.6 citrate buffer. Under these conditions, no cell growth occurred after 48 h on plate count agar. Scanning electron microscopy, light scattering by flow cytometry, and cell volume measurements were compared to evaluate the morphological changes in cells after pressurization. All these methods revealed that cellular morphology was not really affected. Esterase activity, as assessed either by enzymatic activity assays or by carboxy fluorescein diacetate fluorescence monitored by flow cytometry, was dramatically lowered, but not totally obliterated, under the effects of treatment. The measurement of propidium iodide uptake followed by flow cytometry demonstrated that membrane integrity was preserved in a small part of the population, although the membrane potential measured by analytical methods or evaluated by oxonol uptake was reduced from ?86 to ?5 mV. These results showed that such combined methods as fluorescent dyes monitored by flow cytometry and physiological activity measurements provide valuable indications of cellular viability. PMID:11319107

Ritz, M.; Tholozan, J. L.; Federighi, M.; Pilet, M. F.

2001-01-01

319

Microstructured scaffolds for liver tissue cultures of high cell density: morphological and biochemical characterization of tissue aggregates.  

PubMed

Very high cell densities and optimal vascularization characterize among others organs and tissues in vivo. In order to study organ-specific functions in vitro or to make use of them in medical devices/treatments in the future, this natural architecture should be rebuilt. An important aspect in this context is the appropriate ratio of medium to cell volume being so far not optimally reestablished in most of the currently available in vitro systems. To improve such culture conditions, we constructed a microstructure to culture hepatocytes and (without any addition of extracellular matrix material) characterized liver tissue in the form of evenly sized aggregates. The liver-specific differentiation status of such aggregates was monitored by their ability to perform CYP450 dependent xenobiotic metabolism along with the measurement of albumin secretion. Freshly isolated adult rat hepatocytes show an initial loss of total CYP450 content and of associated activities (mixed function oxidases). However, in the aggregate system, this level did not decrease further but remained stable or even increased throughout the culture period of 10-13 days. The CYP450 dependent metabolism of the hepatocytes is able to respond to classic inducing agents. The described culture efficiently supports liver-specific functions of adult rat hepatocytes and seems to be suited not only for use in an extracorporeal liver device but also for the formation of evenly sized small aggregates to be of use in transplantation of differentiated liver tissue. Moreover, after design variations, the microstructure can be applied for functional analysis of metabolically active hepatocytes as well as for toxicological and pharmacological validation. PMID:15770659

Eschbach, Erik; Chatterjee, Shyam S; Nöldner, Michael; Gottwald, Eric; Dertinger, Hermann; Weibezahn, Karl-Friedrich; Knedlitschek, Gudrun

2005-05-15

320

Intestinal spirochetosis: morphological characterization and cultivation of the spirochete Brachyspira aalborgi gen. nov., sp. nov.  

PubMed Central

The ultrastructure of spirochetes obtained from rectal biopsies of patients with intestinal spirochetosis was studied by means of negative staining and ultrathin sectioning. The cells were sigmoidal with tapered ends, 2 to 6 microns long, with a wavelength of 2 microns. Four flagella were inserted at each end of the cells. The maximal cell width was about 0.2 microns. The spirochetes were cultured on tryptose soy blood agar plates. They were anaerobic and grew, although very slowly, at 37 to 38.5 degrees C in an atmosphere of 5% CO2-95% H2. Two types of colonies could be distinguished. The growth characteristics and the morphology of the isolated spirochetes differ from those of previously isolated spirochetal strains. Consequently, it is proposed that the present strains constitute a new genus, Brachyspira, of the family Treponemataceae. The type species is Brachyspira aalborgi, the type strain of which is 513A (NCTC 11492). Images PMID:6186689

Hovind-Hougen, K; Birch-Andersen, A; Henrik-Nielsen, R; Orholm, M; Pedersen, J O; Teglbjaerg, P S; Thaysen, E H

1982-01-01

321

Spectroscopic, morphological, and electrical characterization of PdGe ohmic contacts to n-GaAs  

SciTech Connect

Novel material systems such as ZnS{sub y}Se{sub 1{minus}y} and Zn{sub x}Cd{sub l{minus}x}Te that are commonly grown at low temperatures ({approximately}300 C), require unique, low temperature processing schemes. For example, ohmic contact formation with the common AuGeNi n-GaAs contact is not appropriate for this application due to its relatively high anneal temperature ({approximately}400 C). For this reason, we investigated the effects of anneal temperature (150 to 400 C) and time (5 to 30 min) on the contact resistivity of PdGe to n-GaAs substrates. The contact surface morphology was measured by AFM and the material composition profile was analyzed by XPS. The characteristics of the PdGe contact are compared to the standard AuGeNi n-GaAs contact.

Howard, A.J.; Lovejoy, M.L.; Zavadil, K.R.; Rieger, D.J.; Shul, R.J.; Zolper, J.C. [Sandia National Labs., Albuquerque, NM (United States); Barnes, P.A. [Auburn Univ., AL (United States). Dept. of Physics

1994-10-01

322

Surface morphological, mechanical and thermal characterization of electron beam irradiated fibers  

NASA Astrophysics Data System (ADS)

The surface morphology of henequen irradiated by electron beam has been investigated by atomic force microscopy (AFM). Also, the extents to which electron beam irradiation affected the tensile and thermal properties of henequen fiber were investigated with Instron tensile tests and thermogravimetric analysis (TGA). The AFM studies showed that the pectin, waxy and primary layers (P) of henequen fiber, which have heterogeneous structures, were removed from the fiber surface by electron beam irradiation. The tensile strength and thermal stability of henequen fiber decreased with increasing dose of electron beam. At the irradiation of 10 kGy, the surface roughness increased because of the removal of the pectin, waxy and P layer, but the tensile strength of henequen irradiated with 10 kGy were maintained. It has been suggested that the use of a 10 kGy dose of electron beam to modify the henequen fiber surface can improve the surface properties and preserve the fibers' mechanical and thermal properties.

Choi, Hae Young; Han, Seong Ok; Lee, Jung Soon

2008-12-01

323

Physicochemical Characterization of Capstone Depleted Uranium Aerosols III: Morphologic and Chemical Oxide Analyses  

SciTech Connect

The impact of depleted uranium (DU) penetrators against an armored target causes erosion and fragmentation of the penetrators, the extent of which is dependent on the thickness and material composition of the target. Vigorous oxidation of the DU particles and fragments creates an aerosol of DU oxide particles and DU particle agglomerations combined with target materials. Aerosols from the Capstone DU aerosol study, in which vehicles were perforated by DU penetrators, were evaluated for their oxidation states using X-ray diffraction (XRD) and particle morphologies using scanning electron microscopy/energy dispersive spectrometry (SEM/EDS). The oxidation state of a DU aerosol is important as it offers a clue to its solubility in lung fluids. The XRD analysis showed that the aerosols evaluated were a combination primarily of U3O8 (insoluble) and UO3 (relatively more soluble) phases, though intermediate phases resembling U4O9 and other oxides were prominent in some samples. Analysis of particle residues in the micrometer-size range by SEM/EDS provided microstructural information such as phase composition and distribution, fracture morphology, size distribution, and material homogeneity. Observations from SEM analysis show a wide variability in the shapes of the DU particles. Some of the larger particles appear to have been fractured (perhaps as a result of abrasion and comminution); others were spherical, occasionally with dendritic or lobed surface structures. Amorphous conglomerates containing metals other than uranium were also common, especially with the smallest particle sizes. A few samples seemed to contain small chunks of nearly pure uranium metal, which were verified by EDS to have a higher uranium content exceeding that expected for uranium oxides. Results of the XRD and SEM/EDS analyses were used in other studies described in this issue of The Journal of Health Physics to interpret the results of lung solubility studies and in selecting input parameters for dose assessments.

Krupka, Kenneth M.; Parkhurst, MaryAnn; Gold, Kenneth; Arey, Bruce W.; Jenson, Evan D.; Guilmette, Raymond A.

2009-03-01

324

Physicochemical characterization of Capstone depleted uranium aerosols III: morphologic and chemical oxide analyses.  

PubMed

The impact of depleted uranium (DU) penetrators against an armored target causes erosion and fragmentation of the penetrators, the extent of which is dependent on the thickness and material composition of the target. Vigorous oxidation of the DU particles and fragments creates an aerosol of DU oxide particles and DU particle agglomerations combined with target materials. Aerosols from the Capstone DU aerosol study, in which vehicles were perforated by DU penetrators, were evaluated for their oxidation states using x-ray diffraction (XRD), and particle morphologies were examined using scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS). The oxidation state of a DU aerosol is important as it offers a clue to its solubility in lung fluids. The XRD analysis showed that the aerosols evaluated were a combination primarily of U3O8 (insoluble) and UO3 (relatively more soluble) phases, though intermediate phases resembling U4O9 and other oxides were prominent in some samples. Analysis of particle residues in the micrometer-size range by SEM/EDS provided microstructural information such as phase composition and distribution, fracture morphology, size distribution, and material homogeneity. Observations from SEM analysis show a wide variability in the shapes of the DU particles. Some of the larger particles were spherical, occasionally with dendritic or lobed surface structures. Others appear to have fractures that perhaps resulted from abrasion and comminution, or shear bands that developed from plastic deformation of the DU material. Amorphous conglomerates containing metals other than uranium were also common, especially with the smallest particle sizes. A few samples seemed to contain small bits of nearly pure uranium metal, which were verified by EDS to have a higher uranium content exceeding that expected for uranium oxides. Results of the XRD and SEM/EDS analyses were used in other studies described in this issue of Health Physics to interpret the results of lung solubility studies and in selecting input parameters for dose assessments. PMID:19204486

Krupka, Kenneth M; Parkhurst, Mary Ann; Gold, Kenneth; Arey, Bruce W; Jenson, Evan D; Guilmette, Raymond A

2009-03-01

325

Nitrogen-Fixing Nodule Characterization and Morphology of Four Species in the Northern Intermountain Region  

Microsoft Academic Search

Purshia tridentata (antelope bitterbrush), Ceanothus velutinus (snowbrush), Ceanothus sanguenius (redstem ceanothus), and Shepherdia canadensis (buffaloberry) are native shrubs of the Northern Intermountain Region that are generally characterized as nitrogen-fixing species. These species occupy a range of habitats from steppe to alpine environments. Nodulation of these species is initiated through root infection by Frankia species and the resulting nodules are described

Lee Walls; Benjamin A. Zamora

326

MORPHOLOGICAL AND GENOMIC CHARACTERIZATION OF THE POLYDNAVIRUS ASSOCIATED WITH THE PARASITOID WASP, GLYPTAPANTELES INDIENSIS (HYMENOPTERA: BRACONIDAE)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Glyptapanteles indiensis polydnavirus (GiPDV) is essential for successful parasitization of the larval stage of the lepidopteran Lymantria dispar (gypsy moth) by the endoparasitic wasp, Glyptapanteles indiensis. This virus has not been characterized. Ultrastructural studies of GiPDV showed that th...

327

Morphological and acoustic characterization of Proceratophrys goyana (Lissamphibia: Anura: Odontophrynidae), with the description of a sympatric and related new species.  

PubMed

Proceratophrys goyana was until recently the only species of the genus described from central Brazil. In this paper we characterize the adult morphology and advertisement call of this species, based on data collected at its type-locality (Chapada dos Veadeiros, Goiás, Brazil). These new data allowed us to recognize a new species of Proceratophrys, sympatric to P. goyana, which is described herein. Proceratophrys goyana is mainly characterized by the male SVL = 38.8-46.5 mm; a well-developed and continuous pair of dorsal sagittal ridges; upper eyelids triangular; developed frontoparietal crests, delimiting a shallow depression between them; overall color pattern browned, with the symmetrical dorsal ridges bordered laterally by dark brown undulations. Proceratophrys rotundipalpebra sp. nov. is characterized by the male SVL = 30.4-39.3 mm; the pair of symmetrical dorsal ridges well-developed anteriorly and somewhat interrupted in the sacral region; upper eyelids short and rounded; frontoparietal crests not well-developed; overall color pattern stained by 3-4 tonalities of gray, without a clear background color. The advertisement calls of both species are emitted in a multi-note pattern, each note pulsed, the first and last notes differing from each other and from those amidst the call in temporal features. The description of this new species is another example of the underestimated diversity of Proceratophrys in the Cerrado of central Brazil.  PMID:25113701

Martins, Lucas Borges; Giaretta, Ariovaldo Antonio

2013-01-01

328

Anatomic changes in the macroscopic morphology and microarchitecture of denervated long bone tissue after spinal cord injury in rats.  

PubMed

To study the effects of mechanical loading on bones after SCI, we assessed macro- and microscopic anatomy in rats submitted to passive standing (PS) and electrical stimulation (ES). The study design was based on two main groups of juvenile male Wistar rats with SCI: one was followed for 33 days with therapies starting at day 3 and the other was followed for 63 days with therapies starting at day 33. Both groups were composed of four subgroups (n = 10/group): (1) Sham, (2) SCI, (3) SCI + PS, and (4) SCI + ES. Rehabilitation protocol consisted of a 20-minute session, 3x/wk for 30 days. The animals were sequentially weighed and euthanized. The femur and tibia were assessed macroscopically and microscopically by scanning electronic microscopy (SEM). The SCI rats gained less weight than Sham-operated animals. Significant reduction of bone mass and periosteal radii was observed in the SCI rats, whereas PS and ES efficiently improved the macroscopic parameters. The SEM images showed less and thin trabecular bone in SCI rats. PS and ES efficiently ameliorated the bone microarchitecture deterioration by thickening and increasing the trabeculae. Based on the detrimental changes in bone tissue following SCI, the mechanical loading through weight bearing and muscle contraction may decrease the bone loss and restore the macro- and microanatomy. PMID:25136632

Zamarioli, Ariane; Maranho, Daniel A; Butezloff, Mariana M; Moura, Patrícia A; Volpon, José Batista; Shimano, Antônio C

2014-01-01

329

Quantitative ED-EPMA combined with morphological information for the characterization of individual aerosol particles collected in Incheon, Korea  

NASA Astrophysics Data System (ADS)

A quantitative single-particle analytical technique, called low- Z particle electron probe X-ray microanalysis, combined with the utilization of their morphological information on individual particles, was applied to characterize six aerosol samples collected in one Korean city, Incheon, during March 9-15, 2006. The collected supermicron aerosol particles were classified based on their chemical species and morphology on a single-particle basis. Many different particle types were identified and their emission source, transport, and reactivity in the air were elucidated. In the samples, particles in the "soil-derived particles" group were the most abundant, followed by "reacted sea-salts", "reacted CaCO 3-containing particles", "genuine sea-salts", "reacted sea-salts + others", "Fe-containing particles", "anthropogenic organics", (NH 4) 2SO 4, "K-containing particles", and "fly ash". The application of this single-particle analysis, fully utilizing their chemical compositional and morphological data of individual particles, clearly revealed the different characteristics of the six aerosol samples. For samples S3 and S5, which were sampled during two Asian dust storm events, almost all particles were of soil origin that had not experienced chemical modification and that did not entrain sea-salts during their long-range transport. For sample S1, collected at an episodic period of high PM 10 concentration and haze, anthropogenic, secondary, and soil-derived particles emitted from local sources were predominant. For samples S2, S4, and S6, which were collected on average spring days with respect to their PM 10 concentrations, marine originated particles were the most abundant. Sample S2 seems to have been strongly influenced by emissions from the Yellow Sea and Korean peninsula, sample S4 had the minimum anthropogenic influence among the four samples collected in the absence of any Asian dust storm event, and sample S6 seems to have entrained air pollutants that had been transported from mainland China over the Yellow Sea to Korea.

Kang, SuJin; Hwang, HeeJin; Kang, Sunni; Park, YooMyung; Kim, HyeKyeong; Ro, Chul-Un

330

Spinal Cord Transection-Induced Allodynia in Rats – Behavioral, Physiopathological and Pharmacological Characterization  

PubMed Central

In humans, spinal cord lesions induce not only major motor and neurovegetative deficits but also severe neuropathic pain which is mostly resistant to classical analgesics. Better treatments can be expected from precise characterization of underlying physiopathological mechanisms. This led us to thoroughly investigate (i) mechanical and thermal sensory alterations, (ii) responses to acute treatments with drugs having patent or potential anti-allodynic properties and (iii) the spinal/ganglion expression of transcripts encoding markers of neuronal injury, microglia and astrocyte activation in rats that underwent complete spinal cord transection (SCT). SCT was performed at thoracic T8–T9 level under deep isoflurane anaesthesia, and SCT rats were examined for up to two months post surgery. SCT induced a marked hyper-reflexia at hindpaws and strong mechanical and cold allodynia in a limited (6 cm2) cutaneous territory just rostral to the lesion site. At this level, pressure threshold value to trigger nocifensive reactions to locally applied von Frey filaments was 100-fold lower in SCT- versus sham-operated rats. A marked up-regulation of mRNAs encoding ATF3 (neuronal injury) and glial activation markers (OX-42, GFAP, P2×4, P2×7, TLR4) was observed in spinal cord and/or dorsal root ganglia at T6-T11 levels from day 2 up to day 60 post surgery. Transcripts encoding the proinflammatory cytokines IL-1?, IL-6 and TNF-? were also markedly but differentially up-regulated at T6–T11 levels in SCT rats. Acute treatment with ketamine (50 mg/kg i.p.), morphine (3–10 mg/kg s.c.) and tapentadol (10–20 mg/kg i.p.) significantly increased pressure threshold to trigger nocifensive reaction in the von Frey filaments test, whereas amitriptyline, pregabalin, gabapentin and clonazepam were ineffective. Because all SCT rats developed long lasting, reproducible and stable allodynia, which could be alleviated by drugs effective in humans, thoracic cord transection might be a reliable model for testing innovative therapies aimed at reducing spinal cord lesion-induced central neuropathic pain. PMID:25019623

M'Dahoma, Saďd; Bourgoin, Sylvie; Kayser, Valérie; Barthélémy, Sandrine; Chevarin, Caroline; Chali, Farah; Orsal, Didier; Hamon, Michel

2014-01-01

331

Morphological, Biochemical and Molecular Characterization of Twelve Nitrogen-Fixing Bacteria and Their Response to Various Zinc Concentration  

PubMed Central

Background: Zinc is an essential micronutrient used in the form of zinc sulfate in fertilizers in the agriculture production system. Nitrogen-fixing microorganisms are also of considerable value in promoting soil fertility. Objectives: This study aimed to investigate the degree of sensitivity to varying concentrations of zinc, in the form of ZnSO4, in different strains of Azotobacter chroococcum in a laboratory environment. Materials and Methods: To isolate A. chroococcum strains, soil samples were collected from wheat, corn and asparagus rhizospheres and cultured in media lacking nitrogen at 30?C for 48 hours. Strains were identified based on morphological and biochemical characteristics. The presence of the nitrogenase enzyme system was confirmed by testing for the presence of the nifH gene using PCR analysis. The minimum inhibitory concentration (MIC) and optimal zinc concentration for the growth of each strain was determined. Results: A total of 12 bacterial strains were isolated from six different soil samples. A. chroococcum strains were morphologically and biochemically characterized. The presence of the nifH gene was confirmed in all the strains. MIC and the optimal zinc concentration for bacterial growth were 50 ppm and 20 ppm, respectively. Conclusions: It was concluded that increasing the concentration of zinc in the agricultural soil is harmful to beneficial microorganisms and reduces the soil fertility. A 20-ppm zinc concentration in soil is suggested to be optimal. PMID:25147702

Dadook, Mohammad; Mehrabian, Sedigheh; Salehi, Mitra; Irian, Saeed

2014-01-01

332

A morphological descriptors-based pattern recognition system for the characterization of hip osteoarthritis severity from X-ray images  

NASA Astrophysics Data System (ADS)

A pattern recognition system is proposed for the characterization of hip osteoarthritis (OA) severity. Sixty-four (64) hips, corresponding to 32 unilateral and bilateral OA patients were studied. Employing the Kellgren and Lawrence scale, hips were grouped into three OA severity categories: "Normal", "Mild/Moderate", and "Severe". Utilizing custom-developed software, 64 ROIs, corresponding to patients' radiographic Hip Joint Spaces (HJSs), were determined on digitized radiographs. A Probabilistic Neural Network classifier was designed employing morphological descriptors of the HJS-ROIs. The classifier discriminated successfully between (i) normal and OA hips (92.2% accuracy) and (ii) hips of "Mild/Moderate" OA and of "Severe" OA (91.3% accuracy). The proposed system could contribute in assessing hip OA severity.

Boniatis, I.; Costaridou, L.; Cavouras, D.; Panagiotopoulos, E.; Panayiotakis, G.

2007-10-01

333

Direct image-based fractal characterization of morphologies and structures of wax crystals in waxy crude oils  

NASA Astrophysics Data System (ADS)

The morphology and structure of wax crystals are among the factors dominating rheological characteristics of a waxy crude oil at temperatures below the wax appearance temperature (WAT). In several reported researches fractal dimensions were employed in describing the waxy crude oil microstructures; however, they were all determined via the indirect approach, i.e. deduced from the rheological data. This paper presents a direct fractal characterization approach based on micrographs of wax crystals. The box-counting method is applied to the wax crystal images of three waxy crude oils beneficiated with and without pour-point-depressants (PPDs), and for the fractal measurements the t-distribution tests of hypothesis on linear regression are performed at the significance level of 0.01. It is demonstrated that the boundary fractal dimensions from micrographs of different visual fields of a specimen are almost identical, with the maximum and minimum relative ranges being 9.97% and 1.88% respectively, and with the standard deviation ranging from 0.0549 to 0.0107. Then the wax crystal structures are determined as fractal at the confidence level of 99%. All the listed absolute t-statistics with the minimum of 29.568 are much higher than the corresponding t-quantiles with the maximum of 3.4995. The results also show that the larger value of the boundary box dimension represents the higher complexity and irregularity of the wax crystal morphology. The box dimension increases with decreasing oil temperature for each waxy crude oil. After the oil is beneficiated with a PPD, the box dimension increases at each given temperature. Thus, it is feasible to use fractal dimensions to characterize the waxy crude oil microstructures. This helps to probe the rheology-microstructure relation.

Gao, Peng; Zhang, Jinjun; Ma, Guixia

2006-12-01

334

Characterization of surface morphologies at the Al–Pd–Mn fivefold surface  

Microsoft Academic Search

Fivefold surfaces of Al–Pd–Mn quasicrystal have been prepared under ultra-high vacuum (UHV) by sputtering and annealing above 700K and characterized by electron diffraction, Auger spectroscopy and X-ray photoemission spectroscopy (LEED, AES, XPS). X-ray reflectivity at grazing incidence reveals that an in situ temperature annealing at 900K is necessary to irreversibly produce the signature of a flat and bulk terminated surface.

Giovanni Cappello; Frank Schmithüsen; Joël Chevrier; Fabio Comin; Andreas Stierle; Vincenzo Formoso; Marc de Boissieu; Michel Boudard; T. A Lograsso; Cynthia Jenks; Dwigth Delaney

2000-01-01

335

Convergence of goals: phylogenetical, morphological, and physiological characterization of tolerance to drought stress in tall fescue (Festuca arundinacea Schreb.).  

PubMed

The aim of this study is to find Iranian tall fescue accessions that tolerate drought stress and investigation on phylogenetical, morphological, and physiological characterization of them. For this propose, inter-simple sequence repeats (ISSR) markers were used to examine the genetic variability of accessions from different provinces of Iran. Of 21 primers, 20 primers generated highly reproducible fragments. Using these primers, 390 discernible DNA fragments were produced with 367 (93.95 %) being polymorphic. The polymorphic information content (PIC) values ranged from 0.948 to 0.976, with a mean PIC value of 0.969. Probability identity (PI) and discriminating power (D = 1-PI) among the primers ranged from 0.001 to 0.004 and 0.998 to 0.995, respectively. A binary qualitative data matrix was constructed. Data analyses were performed using the NTSYS software and the similarity values were used to generate a dendrogram via UPGMA. To study the drought stress, plants were irrigated at 25 % FC condition for three times. Fresh leaves were collected to measure physiological characters including: superoxide dismutase, catalase, and peroxidase activities and proline and total chlorophyll content at two times, before and after stress application. Relative water content, fresh and dry weight ratio, survival percentage, and visual quality were evaluated after stress. Morphological and physiological characters were assessed in order to classify accessions as either tolerant or sensitive using Ward's method of Hierarchical cluster analysis in SPSS software. The results of present study demonstrated that the ISSR markers are useful for studying tall fescue genetic diversity. Convergence of morphological and physiological characterizations during drought stress and phylogenetic relationship results showed that accessions can be grouped into four clusters; drought-tolerant accessions that collected from west of Iran, drought-tolerant accessions collected from northwest of Iran, drought semi-tolerant accessions collected from center of Iran, and drought-sensitive accessions collected from north of Iran. Data presented could be used to classify the tall fescue accessions based on suitability of cultivation in the regions studied or the regions with the similar environmental condition. PMID:24078217

Salehi, Mohammadreza; Salehi, Hassan; xNiazi, Hassan; Ghobadi, Cyrus

2014-03-01

336

Main airborne Ascomycota spores: characterization by culture, spore morphology, ribosomal DNA sequences and enzymatic analysis.  

PubMed

The aim of this work was to identify the main allergy-related Ascomycetes fungal spores present in the atmosphere of Porto, using different and complementary techniques. The atmospheric sampling, performed in the atmosphere of Porto (Portugal) from August 2006 to July 2008, indicated Cladosporium, Penicillium, Aspergillus and Alternaria as the main fungal spore taxa. Alternaria and Cladosporium peaks were registered during summer. Aspergillus and Penicillium highest values were registered from late winter to early spring. Additionally, the Andersen sampler allowed the culture and isolation of the collected viable spores subsequently used for different identification approaches. The internal-transcribed spacer region of the nuclear ribosomal repeat unit sequences of airborne Ascomycetes fungi isolates revealed 11 taxonomically related fungal species. Among the identified taxa, Penicillum and Aspergillus presented the highest diversity, while only one species of Cladosporium and Alternaria, respectively, were identified. All selected fungal spore taxa possessed phosphatase, esterase, leucine arylamidase and beta-glucosidase enzymatic activity, while none had lipase, cystine arylamidase, trypsin or beta-glucuronidase activity. The association between the spore cell wall morphology, DNA-based techniques and enzymatic activity approaches allowed a more reliable identification procedure of the airborne Ascomycota fungal spores. PMID:20143229

Oliveira, Manuela; Amorim, M Isabel; Ferreira, Elsa; Delgado, Luís; Abreu, Ilda

2010-04-01

337

Characterization of Morphology and Composition of Inorganic Fillers in Dental Alginates  

PubMed Central

Energy dispersive X-ray spectroscopy microanalysis (EDX), scanning electron microscopy (SEM), and Archimedes' Principle were used to determine the characteristics of inorganic filler particles in five dental alginates, including Cavex ColorChange (C), Hydrogum 5 (H5), Hydrogum (H), Orthoprint (O), and Jeltrate Plus (JP). The different alginate powders (0.5?mg) were fixed on plastic stubs (n = 5) and sputter coated with carbon for EDX analysis, then coated with gold, and observed using SEM. Volume fractions were determined by weighing a sample of each material in water before and after calcining at 450°C for 3?h. The alginate materials were mainly composed of silicon (Si) by weight (C—81.59%, H—79.89%, O—78.87%, H5—77.95%, JP—66.88%, wt). The filler fractions in volume (vt) were as follows: H5—84.85%, JP—74.76%, H—70.03%, O—68.31%, and C—56.10%. The tested materials demonstrated important differences in the inorganic elemental composition, filler fraction, and particle morphology. PMID:25165690

Guiraldo, Ricardo Danil; Berger, Sandrine Bittencourt; Consani, Rafael Leonardo Xediek; Consani, Simonides; de Carvalho, Rodrigo Varella; Lopes, Murilo Baena; Meneghel, Luciana Lira; da Silva, Fabiane Borges; Sinhoreti, Mário Alexandre Coelho

2014-01-01

338

Morphological and structural characterization of SiC based composite nanostructures  

NASA Astrophysics Data System (ADS)

This paper reports on producing SiC based nanostructures (SiC, W-SiC, CNS-SiC) by pulsed laser deposition (PLD) and radio-frequency plasma assisted PLD. Simple and composite targets (SiC, 3/4 SiC + 1/4 tungsten and 3/4 SiC + 1/4 graphite) were irradiated by a 266 nm pulsed laser beam having a pulse duration of 7 ns. The silicon substrates were kept either at room temperature or heated up to 600 °C. The depositions were performed in argon at various pressures, ranging from 0.05 mbar up to 2 mbar. The influence of deposition parameters on the structure, surface morphology and composition of different SiC based structures was studied by atomic force microscopy, scanning electron microscopy, secondary ion mass spectrometry, transmission electron microscopy and selected area electron diffraction. Fibers, tubes, nanoparticles and rolled sheets structures were obtained by varying laser fluence, substrate temperature, gas pressure and radio-frequency power.

Filipescu, M.; Stokker-Cheregi, F.; Colceag, D.; Nedelcea, A.; Birjega, R.; Nistor, L. C.; Dinescu, M.

2013-08-01

339

Plasma morphology and induced airflow characterization of a DBD actuator with serrated electrode  

NASA Astrophysics Data System (ADS)

Plasma morphology and airflow induced by a dielectric barrier discharge (DBD) actuator, whose exposed electrode geometry is designed with a serrated configuration, are investigated in quiescent air and compared with a DBD actuator consisting of electrodes designed with a standard linear strip configuration. ICCD imaging, electrical measurements and three-component laser Doppler velocimetry were carried out to compare various features of these two actuators. With the serrated configuration, ICCD images of the discharge show that streamers are bent, whereas with the linear configuration they are straight. These curved streamers induce a three-dimensional flow topology, which is confirmed by friction line visualization and velocity measurements. Whereas a two-dimensional wall-jet is induced with the linear configuration, a transverse velocity component is measured with the serrated configuration, implying the creation of spanwise-periodic vorticity. Phase-averaged velocity measurements allow the temporal variation of this transverse velocity to be highlighted. On both sides of a tooth, it has qualitatively the same variation as the longitudinal velocity with respect to the negative or positive half-cycles of the high voltage signal. Moreover, with the same electrical operating parameters, the measured longitudinal velocity was higher, particularly at the tips.

Joussot, R.; Leroy, A.; Weber, R.; Rabat, H.; Loyer, S.; Hong, D.

2013-03-01

340

Gold nanoparticles on the surface of soda-lime glass: morphological, linear and nonlinear optical characterization.  

PubMed

Materials presenting high optical nonlinearity, such as materials containing metal nanoparticles (NPs), can be used in various applications in photonics. This motivated the research presented in this paper, where morphological, linear and nonlinear optical characteristics of gold NPs on the surface of bulk soda-lime glass substrates were investigated as a function of nanoparticle height. The NPs were obtained by annealing gold (Au) thin films previously deposited on the substrates. Pixel intensity histogram fitting on Atomic Force Microscopy (AFM) images was performed to obtain the thickness of the deposited film. Image analysis was employed to obtain the statistical distribution of the average height of the NPs. In addition, absorbance spectra of the samples before and after annealing were measured. Finally, the nonlinear refractive index (n2) and the nonlinear absorption index (?2) at 800 nm were obtained before and after annealing by using the thermally managed eclipse Z-scan (TM-EZ) technique with a Ti:Sapphire laser (150 fs pulses). Results show that both n2 and ?2 at this wavelength change signs after the annealing and that the samples presented a high nonlinear refractive index. PMID:22418350

Romani, E C; Vitoreti, Douglas; Gouvęa, Paula M P; Caldas, P G; Prioli, R; Paciornik, S; Fokine, Michael; Braga, Arthur M B; Gomes, Anderson S L; Carvalho, Isabel C S

2012-02-27

341

Synthesis and characterization of different MnO2 morphologies for lithium-air batteries  

NASA Astrophysics Data System (ADS)

Manganese dioxide (MnO2) was synthesized in the forms of nanorods, nanoparticles, and mesoporous structures and the characteristics of these materials were investigated. Crystallinities were studied by x-ray diffraction and morphologies by scanning and transmission electron microscopy. Average pore sizes and specific surface areas were analyzed using the Barret-Joyner-Halenda and Brunauer-Emmett-Teller methods, respectively. Samples were also studied by cyclic voltammetry using 1M aqueous KOH solution saturated with either O2 or N2 as electrolytes to investigate their ORR (oxygen reduction reaction) and OER (oxygen evolution reaction) activities. Of the samples produced, mesoporous MnO2 exhibited the highest ORR and OER catalytic activities. Mesoporous MnO2 supported on a gas diffusion layer was also used as a catalyst on the air electrode (cathode) of a lithium-air battery in organic electrolyte. The charge-discharge behavior of mesoporous MnO2 was investigated at a current density 0.2 mAcm-2 in a pure oxygen environment. Mesoporous MnO2 electrodes showed stable cycleability up to 65 cycles at a cell capacity of 700 mAhg-1.

Choi, Hyun-A.; Jang, Hyuk; Hwang, Hyein; Choi, Mincheol; Lim, Dongwook; Shim, Sang Eun; Baeck, Sung-Hyeon

2014-09-01

342

Morphological and microstructural characterization of nanostructured pure ?-phase W coatings on a wide thickness range  

NASA Astrophysics Data System (ADS)

Nanostructured tungsten (nanoW) coatings have been deposited by DC magnetron sputtering. First, the influence of the sputtering power on the adhesion of the coatings to the substrate was investigated by depositing coatings at powers varying from 30 up to 220 W. Non-delaminated coatings were achieved at powers ?50 W. Second, the influence of coating thickness on the morphological, microstructural and mechanical properties was investigated for films deposited at 50 W with thicknesses varying from 30 nm up to ?4.0 ?m. SEM images reveal that all the films are highly compact, consisting of nanometer sized columns that grow perpendicular to the substrate. XRD data evidence that films are monophasic, being made of pure ?-phase. All coatings show compressive stress and low micro-strain. Nanoindentation tests show that coatings have a hardness higher than that reported for coarse grained W. No significant dependence of the previous properties on coating thickness was observed. Finally, the influence of the substrate on coatings properties was studied, by depositing a W coating at a power of 50 W on a commercial steel substrate: no significant dependence was found.

Gordillo, N.; Panizo-Laiz, M.; Tejado, E.; Fernandez-Martinez, I.; Rivera, A.; Pastor, J. Y.; Castro, C. Gómez de; del Rio, J.; Perlado, J. M.; Gonzalez-Arrabal, R.

2014-10-01

343

Characterization of Adaptation by Morphology in a Planar Biological Network of Plasmodial Slime Mold  

NASA Astrophysics Data System (ADS)

Growth processes of a planar biological network of plasmodium of a true slime mold, Physarum polycephalum, were analyzed quantitatively. The plasmodium forms a transportation network through which protoplasm conveys nutrients, oxygen, and cellular organelles similarly to blood in a mammalian vascular network. To analyze the network structure, vertices were defined at tube bifurcation points. Then edges were defined for the tubes connecting both end vertices. Morphological analysis was attempted along with conventional topological analysis, revealing that the growth process of the plasmodial network structure depends on environmental conditions. In an attractive condition, the network is a polygonal lattice with more than six edges per vertex at the early stage and the hexagonal lattice at a later stage. Through all growing stages, the tube structure was not highly developed but an unstructured protoplasmic thin sheet was dominantly formed. The network size is small. In contrast, in the repulsive condition, the network is a mixture of polygonal lattice and tree-graph. More specifically, the polygonal lattice has more than six edges per vertex in the early stage, then a tree-graph structure is added to the lattice network at a later stage. The thick tube structure was highly developed. The network size, in the meaning of Euclidean distance but not topological one, grows considerably. Finally, the biological meaning of the environment-dependent network structure in the plasmodium is discussed.

Ito, Masateru; Okamoto, Riki; Takamatsu, Atsuko

2011-07-01

344

Japanese Bobtail: vertebral morphology and genetic characterization of an established cat breed.  

PubMed

Several cat breeds are defined by morphological variation of the tail. The Japanese Bobtail is a breed that has been accepted for registration only within the past 50 years; however, the congenital kinked tail variants defining this breed were documented in the Far East centuries ago and the cats are considered 'good luck' in several Asian cultures. The recent discovery of the mutation for the tailless Manx phenotype has demonstrated that the Japanese Bobtail does not have a causative mutation in the same gene (T-Box). Here, a simple segregation analysis of cats bred from a pedigreed Japanese Bobtail demonstrated a simple autosomal dominant mode of inheritance with variable expression of the tail length and kink placement. Unexpectedly, radiological examinations of the entire vertebral column of kink-tailed cats indicated variation from the normal vertebral feline formula (C7, T13, L7, S3, Cd20-24), including cats with mostly one reduction of thoracic vertebrae (C7, T12, L7, S3), and an average of 15.8 caudal vertebrae. A few cats had variation in the number of cervical vertebrae. Several transitional vertebrae and anomalous ribs were noted. One cat had a bifid vertebra in the tail. Most cats had hemivertebrae that were usually included in the tail kink, one of which was demonstrated by gross pathology and histopathology. The abnormal vertebral formula or the placement of the kink in the tail did not coincide with morbidity or mortality. PMID:25488973

Pollard, Rachel E; Koehne, Amanda L; Peterson, Carlyn B; Lyons, Leslie A

2014-12-01

345

Characterization of morphology and composition of inorganic fillers in dental alginates.  

PubMed

Energy dispersive X-ray spectroscopy microanalysis (EDX), scanning electron microscopy (SEM), and Archimedes' Principle were used to determine the characteristics of inorganic filler particles in five dental alginates, including Cavex ColorChange (C), Hydrogum 5 (H5), Hydrogum (H), Orthoprint (O), and Jeltrate Plus (JP). The different alginate powders (0.5 mg) were fixed on plastic stubs (n = 5) and sputter coated with carbon for EDX analysis, then coated with gold, and observed using SEM. Volume fractions were determined by weighing a sample of each material in water before and after calcining at 450(°)C for 3 h. The alginate materials were mainly composed of silicon (Si) by weight (C-81.59%, H-79.89%, O-78.87%, H5-77.95%, JP-66.88%, wt). The filler fractions in volume (vt) were as follows: H5-84.85%, JP-74.76%, H-70.03%, O-68.31%, and C-56.10%. The tested materials demonstrated important differences in the inorganic elemental composition, filler fraction, and particle morphology. PMID:25165690

Guiraldo, Ricardo Danil; Berger, Sandrine Bittencourt; Consani, Rafael Leonardo Xediek; Consani, Simonides; de Carvalho, Rodrigo Varella; Lopes, Murilo Baena; Meneghel, Luciana Lira; da Silva, Fabiane Borges; Sinhoreti, Mário Alexandre Coelho

2014-01-01

346

Pharmacological characterization of the bradykinin B2 receptor antagonist MEN16132 in rat in vitro bioassays.  

PubMed

The pharmacological profile of the bradykinin B(2) receptor antagonist MEN16132 at the rat B(2) receptor has been investigated and compared with that of icatibant (formerly Hoe 140). Antagonist affinity has been measured through radioligand binding experiments with membranes prepared from uterine and airway tissue. MEN16132 inhibited [(3)H]bradykinin binding with subnanomolar affinity (pK(i) values 10.4 and 10.1 in the uterus and airways, respectively), and was about 3-fold less potent than icatibant (pK(i) values 10.9 and 10.5). Antagonist potency has been estimated towards bradykinin-induced contractility of uterine and urinary bladder smooth muscle preparations. In these assays MEN16132 (pK(B): 9.7 both in uterus and bladder) was about 10-fold more potent than icatibant [pK(B): 8.8 in uterus, and pK(B) 8.0 in urinary bladder, as from Meini, S., Patacchini, R., Giuliani, S., Lazzeri, M., Turini, D., Maggi, C.A., Lecci, A., 2000a. Characterization of bradykinin B(2) receptor antagonists in human and rat urinary bladder. Eur. J. Pharmacol. 388, 177-182]. Washout experiments conducted in the uterine preparation indicated for MEN16132 (100 nM) a slower reversibility than icatibant (300 nM).Altogether present results indicate that MEN16132 displays high affinity and potency also for the rat bradykinin B(2) receptor, and thus is suitable for further investigations in pathophysiological models in this species. PMID:19445925

Meini, Stefania; Cucchi, Paola; Catalani, Claudio; Bellucci, Francesca; Giuliani, Sandro; Santicioli, Paolo; Maggi, Carlo Alberto

2009-08-01

347

Human, rat and chicken small intestinal Na+-Cl?-creatine transporter: functional, molecular characterization and localization  

PubMed Central

In spite of all the fascinating properties of oral creatine supplementation, the mechanism(s) mediating its intestinal absorption has(have) not been investigated. The purpose of this study was to characterize intestinal creatine transport. [14C]Creatine uptake was measured in chicken enterocytes and rat ileum, and expression of the creatine transporter CRT was examined in human, rat and chicken small intestine by reverse transcription-polymerase chain reaction, Northern blot, in situ hybridization, immunoblotting and immunohistochemistry. Results show that enterocytes accumulate creatine against its concentration gradient. This accumulation was electrogenic, Na+- and Cl?-dependent, with a probable stoichiometry of 2 Na+: 1 Cl?: 1 creatine, and inhibited by ouabain and iodoacetic acid. The kinetic study revealed a Km for creatine of 29 ?m. [14C]Creatine uptake was efficiently antagonized by non-labelled creatine, guanidinopropionic acid and cyclocreatine. More distant structural analogues of creatine, such as GABA, choline, glycine, ?-alanine, taurine and betaine, had no effect on intestinal creatine uptake, indicating a high substrate specificity of the creatine transporter. Consistent with these functional data, messenger RNA for CRT was detected only in the cells lining the intestinal villus. The sequences of partial clones, and of the full-length cDNA clone, isolated from human and rat small intestine were identical to previously cloned CRT cDNAs. Immunological analysis revealed that CRT protein was mainly associated with the apical membrane of the enterocytes. This study reports for the first time that mammalian and avian enterocytes express CRT along the villus, where it mediates high-affinity, Na+- and Cl?-dependent, apical creatine uptake. PMID:12433955

Peral, M J; García-Delgado, M; Calonge, M L; Durán, J M; De La Horra, M C; Wallimann, T; Speer, O; Ilundáin, A A

2002-01-01

348

Human, rat and chicken small intestinal Na+ - Cl- -creatine transporter: functional, molecular characterization and localization.  

PubMed

In spite of all the fascinating properties of oral creatine supplementation, the mechanism(s) mediating its intestinal absorption has(have) not been investigated. The purpose of this study was to characterize intestinal creatine transport. [(14)C] creatine uptake was measured in chicken enterocytes and rat ileum, and expression of the creatine transporter CRT was examined in human, rat and chicken small intestine by reverse transcription-polymerase chain reaction, Northern blot, in situ hybridization, immunoblotting and immunohistochemistry. Results show that enterocytes accumulate creatine against its concentration gradient. This accumulation was electrogenic, Na(+)- and Cl(-)-dependent, with a probable stoichiometry of 2 Na(+): 1 Cl(-): 1 creatine, and inhibited by ouabain and iodoacetic acid. The kinetic study revealed a K(m) for creatine of 29 microM. [(14)C] creatine uptake was efficiently antagonized by non-labelled creatine, guanidinopropionic acid and cyclocreatine. More distant structural analogues of creatine, such as GABA, choline, glycine, beta-alanine, taurine and betaine, had no effect on intestinal creatine uptake, indicating a high substrate specificity of the creatine transporter. Consistent with these functional data, messenger RNA for CRT was detected only in the cells lining the intestinal villus. The sequences of partial clones, and of the full-length cDNA clone, isolated from human and rat small intestine were identical to previously cloned CRT cDNAs. Immunological analysis revealed that CRT protein was mainly associated with the apical membrane of the enterocytes. This study reports for the first time that mammalian and avian enterocytes express CRT along the villus, where it mediates high-affinity, Na(+)- and Cl(-)-dependent, apical creatine uptake. PMID:12433955

Peral, M J; García-Delgado, M; Calonge, M L; Durán, J M; De La Horra, M C; Wallimann, T; Speer, O; Ilundáin, A

2002-11-15

349

Characterization of homogeneous recombinant rat ovarian 20alpha-hydroxysteroid dehydrogenase: fluorescent properties and inhibition profile.  

PubMed

In rat ovary, 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD), a member of the aldo-keto reductase (AKR) superfamily, converts progesterone into the inactive progestin 20alpha-hydroxyprogesterone and has been implicated in the termination of pregnancy. Here we report a convenient overexpression system that permits the purification of milligram quantities of homogeneous recombinant 20alpha-HSD with wild-type enzyme activity. The availability of this enzyme has permitted detailed kinetic, inhibition and fluorescence analyses. The enzyme exhibited narrow steroid specificity, catalysing reactions only at C-20; it reduced progesterone and 17alpha-hydroxyprogesterone and oxidized 20alpha-hydroxypregnanes. It also turned over common AKR substrates, such as 9, 10-phenanthrenequinone and 4-nitrobenzaldehyde. The intrinsic fluorescence spectrum of 20alpha-HSD was characterized and was quenched on the binding of NADP(H), yielding a KNADPd of 0.36 microM and a KNADPHd of 0.64 microM. NADP(H) binding generated an energy transfer band that could not be quenched by steroids. Inhibition studies conducted with non-steroidal and steroidal anti-inflammatory drugs and synthetic oestrogens indicated that even though rat ovarian 20alpha-HSD and rat liver 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD) share more than 67% amino acid identity, their inhibition profiles are markedly different. Unlike 3alpha-HSD, most of these compounds did not inhibit 20alpha-HSD. Only meclofenamic acid and hexoestrol were potent competitive inhibitors for 20alpha-HSD, yielding K(i) values of 18.9 and 14.3 microM respectively. These studies suggest that selective non-steroidal AKR inhibitors could be developed for 20alpha-HSD that might be useful in maintaining pregnancy and that specific inhibitors might be developed from either N-phenylanthranilates or biphenols. PMID:10417353

Ma, H; Penning, T M

1999-08-01

350

Characterization and intraspinal grafting of EGF\\/bFGF-dependent neurospheres derived from embryonic rat spinal cord  

Microsoft Academic Search

Recent advances in the isolation and characterization of neural precursor cells suggest that they have properties that would make them useful transplants for the treatment of central nervous system disorders. We demonstrate here that spinal cord cells isolated from embryonic day 14 Sprague–Dawley and Fischer 344 rats possess characteristics of precursor cells. They proliferate as undifferentiated neurospheres in the presence

Stella Y Chow; Jon Moul; Chris A Tobias; B. Timothy Himes; Yi Liu; Maria Obrocka; Lisa Hodge; Alan Tessler; Itzhak Fischer

2000-01-01

351

CARDIAC MORPHOLOGY AND FUNCTION FOLLOWING LONG-TERM EXPOSURE TO CARBON MONOXIDE AT HIGH ALTITUDE IN RATS  

Microsoft Academic Search

Although chronic exposure to high altitude or carbon monoxide (CO) induces several cardiovascular adaptations in mammals, very little information is available on the cardiovascular effects due to exposure to these concomitant stresses. In particular, cardiac functional responses to chronic CO inhalation at high altitude has never been investigated. Thirty-two male Dark Agouti rats were exposed for 10 wk in steel

Alexandre Melin; Philippe Obert; Manuel Rebocho; Pierre Bonnet

2002-01-01

352

FATE OF ADRIAMYCIN-INDUCED DILATED RENAL PELVIS IN THE FETAL RAT: FUNCTIONAL AND MORPHOLOGICAL EFFECTS IN THE OFFSPRING  

EPA Science Inventory

Previously the authors reported that gestational exposure to Adriamycin, an anthracycline antibiotic used in the treatment of neoplasms, reduced renal function in the neonatal rat, and the authors suggested that alterations in the development of the renal papilla might be respons...

353

Aminophylline exacerbates status epilepticus-induced neuronal damages in immature rats: a morphological, motor and behavioral study  

Microsoft Academic Search

Adenosine is an endogenous modulator that has an inhibitory effect on neuronal activity. The aim of this work was to investigate the role of aminophylline, an adenosine receptor antagonist, on the long-term effects of status epilepticus (SE) in the developing brain. Four groups of rats at the postnatal age of 12 days were intraperitoneally administered with saline, aminophylline (50 mg\\/kg),

Pi-Lien Hung; Ming-Chi Lai; San Nan Yang; Chih-Lu Wang; Chia-Wei Liou; Chia-Lu Wu; Tzu-Jou Wang; Li-Tung Huang

2002-01-01

354

Characterization of NO-producing neurons in the rat corpus callosum  

PubMed Central

Introduction The aim of this study was to determine the presence and distribution of nitric oxide (NO)-producing neurons in the rat corpus callosum (cc). Material and methods To investigate this aspect of cc organization we used nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-d) histochemistry and neuronal NO synthase (nNOS) immunocytochemistry. Results Intense NADPH-d-positive (NADPH-d+) neurons were found along the rostrocaudal extension of the cc (sagittal sections). They were more numerous in the lateral cc and gradually decreased in the more medial regions, where they were very few or absent. The Golgi-like appearance of NADPH-d+ intracallosal neurons allowed dividing them into five morphological types: (1) bipolar; (2) fusiform; (3) round; (4) polygonal; and (5) pyramidal. The number of NADPH-d+ neurons (both hemispheres) was counted in two brains using 50-?m thick sections. In the first brain, counts involved 145 sections and neurons were 2959; in the second, 2227 neurons were counted in 130 sections. The distribution and morphology of nNOS-immunopositive (nNOSIP) neurons was identical to that of NADPH-d+neurons. Some of these neurons were observed in the cc ependymal region, where they might be in contact with cerebrospinal fluid (CSF), monitoring its composition, pH, and osmolality changes, or playing a role in regulating the synthesis and release of several peptides. The somatic, dendritic, and axonal processes of many NADPH-d+/nNOSIP neurons were closely associated with intracallosal blood vessels. Conclusions Such close relationship raises the possibility that these neurons are a major source of NO during neural activity. As NO is a potent vasodilator, these findings strongly suggest that NO-positive neurons transduce neuronal signals into vascular responses in selected cc regions, thus giving rise to hemodynamic changes detectable by neuroimaging. PMID:24944862

Barbaresi, Paolo; Fabri, Mara; Mensŕ, Emanuela

2014-01-01

355

Characterization of weight loss and weight regain mechanisms after Roux-en-Y gastric bypass in rats.  

PubMed

Roux-en-Y gastric bypass (RYGB) is the most effective therapy for morbid obesity, but it has a approximately 20% failure rate. To test our hypothesis that outcome depends on differential modifications of several energy-related systems, we used our established RYGB model in Sprague-Dawley diet-induced obese (DIO) rats to determine mechanisms contributing to successful (RGYB-S) or failed (RYGB-F) RYGB. DIO rats were randomized to RYGB, sham-operated Obese, and sham-operated obese pair-fed linked to RYGB (PF) groups. Body weight (BW), caloric intake (CI), and fecal output (FO) were recorded daily for 90 days, food efficiency (FE) was calculated, and morphological changes were determined. d-Xylose and fat absorption were studied. Glucose-stimulated vagal efferent nerve firing rates of stomach were recorded. Gut, adipose, and thyroid hormones were measured in plasma. Mitochondrial respiratory complexes in skeletal muscle and expression of energy-related hypothalamic and fat peptides, receptors, and enzymes were quantified. A 25% failure rate occurred. RYGB-S, RYGB-F, and PF rats showed rapid BW decrease vs. Obese rats, followed by sustained BW loss in RYGB-S rats. RYGB-F and PF rats gradually increased BW. BW loss in RYGB-S rats is achieved not only by RYGB-induced decreased CI and increased FO, but also via sympathetic nervous system activation, driven by increased peptide YY, CRF, and orexin signaling, decreasing FE and energy storage, demonstrated by reduced fat mass associated with the upregulation of mitochondrial uncoupling protein-2 in fat. These events override the compensatory response to the drop in leptin levels aimed at conserving energy. PMID:17626126

Guijarro, Ana; Suzuki, Susumu; Chen, Chung; Kirchner, Henriette; Middleton, Frank A; Nadtochiy, Sergiy; Brookes, Paul S; Niijima, Akira; Inui, Akio; Meguid, Michael M

2007-10-01

356

Experiment K-6-16. Morphological examination of rat testes. The effect of Cosmos 1887 flight on spermatogonial population and testosterone level in rat testes  

NASA Technical Reports Server (NTRS)

Testes from rats flown on Cosmos 1887 for twelve and a half days were compared to basal control, synchronous control and vivarium maintained rats. When the mean weights of flight testes, normalized for weight/100 gms, were compared to the vivarium controls they were 6.7 percent lighter. Although the flight testes were lighter than the synchronous, the difference is not significant. Counts of spermatogonial cells from 5 animals in each group revealed a 4 percent decrease in flight compared to vivarium controls. In both cases the t-Test significance was less than 0.02. The serum testosterone levels of all animals (flight, synchronous and vivarium) were significantly below the basal controls.

Philpott, D. E.; Kato, K.; Stevenson, J.; Vasques, M.; Sapp, W.; Williams, C.; Popova, I. A.; Serova, L. V.

1990-01-01

357

[Characterization of fullerene C60 peroral toxicity to rats in the 92-day experiment].  

PubMed

Toxicity of fullerene C60 in male Wistar rats under conditions of a daily intragastric administration at doses of 0.1; 1 and 10 mg/kg body weight for 92 days was studied. Integral, biochemical, physiological, hematological, immunological indicators were determined that characterized the body condition of animals together with fullerene C60 biodistribution in organs and tissues of rats. Majority of the results didn't show any influence of fullerene C60 on animals treated with it in the whole range of doses studied. On the other hand, some of the data not related to the action of the components used in carrier solution, demonstrated dose-dependent variation: found increased activity on 21-35% in the CYP2B1 at doses of 1 mg/kg and 10 mg/kg body weight, and reduced concentration of uric acid and increasing concentrations of urea at 10 mg/kg body weight. Nevertheless, these changes were within the physiological range of variability. However, it is worth noting an important significant (p = 0.02) increase of the absorption for antigenic proteins in the digestive tract in animals treated with fullerene C60 at a dose of 10 mg/kg, suggesting a marked effect on the intestinal wall. PMID:23461168

Shipelin, V A; Avren'eva, L I; Guseva, G V; Trushina, É N; Mustafina, O K; Selifanov, A V; Soto, S Kh; Mal'tsev, G Iu; Gmoshinski?, I V; Khotimchenko, S A

2012-01-01

358

Triamcinolone acetonide-Eudragit(®) RS100 nanofibers and nanobeads: Morphological and physicochemical characterization.  

PubMed

Context and objective: The aim of the present research was to fabricate triamcinolone acetonide (TA)-Eudragit(®) RS100 nanostructures using the electrospraying method. Materials and methods: The physicochemical properties of the electrosprayed formulations as well as drug release patterns were assessed. The particle size and morphology were evaluated using scanning electron microscopy. X-ray crystallography and differential scanning calorimetry were also conducted to investigate the crystallinity and polymorphic alterations of the drug in the formulations. Probable chemical interactions between the drug and the carrier during the preparation process were analyzed using FT-IR spectroscopy. The drug release kinetic was also considered to predict the release mechanism. Results and discussion: Increasing the concentration of injected polymer solution resulted in the formation of more fibers and fewer beads, with the particle diameter ranging from 60 nm to a few micrometers based on the drug: polymer ratio. The drug crystallinity was notably decreased during the electrospraying process; however, no interaction between drug and polymer was detected. The electrosprayed formulations with 1:10 drug: polymer ratio showed an almost similar drug release rate compared to the pure drug, while those with 1:5 ratio revealed slower release profiles. The release data were best fitted to the Weibull model, so that the corresponding shape factor values of the Weibull model were less than 0.75, indicating the diffusion controlled release mechanism. Conclusion: Our findings revealed that TA loaded Eudragit(®) RS100 nanofibers and nanobeads were properly prepared by the electrospraying method, which is a simple, surfactant-free and cost effective technique for producing drug: polymer nanostructures. PMID:25180944

Payab, Shahriar; Davaran, Soodabeh; Tanhaei, Ali; Fayyazi, Behnam; Jahangiri, Azin; Farzaneh, Amir; Adibkia, Khosro

2014-09-01

359

Physicochemical, morphological, and rheological characterization of Xanthosoma robustum Lego-like starch.  

PubMed

This work presents the physicochemical and pasting characterization of isolated mafafa starch and mafafa flour (Xanthosoma robustum). According to SEM images of mafafa starches in the tuber, these starches form Lego-like shaped structures with diameters between 8 and 35 ?m conformed by several starch granules of wedge shape that range from 2 to 7 ?m. The isolated mafafa starch is characterized by its low contents of protein, fat, and ash. The starch content in isolated starch was found to be 88.58% while the amylose content obtained was 35.43%. X-ray diffraction studies confirm that isolated starch is composed mainly by amylopectin. These results were confirmed by differential scanning calorimetry and thermo gravimetric analysis. This is the first report of the molecular parameters for mafafa starch: molar mass that ranged between 2×10(8) and 4×10(8) g/mol, size (Rg) value between 279 and 295 nm, and molecular density value between 9.2 and 9.7 g/(mol nm(3)). This study indicates that mafafa starch shows long chains of amylopectin this fact contributes to higher viscosity development and higher gel stability. The obtained gel phase is transparent in the UV-vis region. The viscosity, gel stability and optical properties suggest that there is potential for mafafa starch applications in the food industry. PMID:24463263

Londońo-Restrepo, Sandra M; Rincón-Londońo, Natalia; Contreras-Padilla, Margarita; Acosta-Osorio, Andrés A; Bello-Pérez, Luis A; Lucas-Aguirre, Juan C; Quintero, Víctor D; Pineda-Gómez, Posidia; del Real-López, Alicia; Rodríguez-García, Mario E

2014-04-01

360

Characterization of an ATPase on the inside of rat-liver nuclear envelopes by affinity labeling.  

PubMed

Nuclear envelope membranes from rat liver cells contain ATPases, one of which can be inhibited and irreversibly labeled by (S-dinitrophenyl)-6-mercaptopurine riboside triphosphate. Inhibition and covalent substitution of the ATPase are achieved only after disruption of the nuclei, the ATP analogue is inactive on the ATPase activity of whole nuclei or on vesicles of the membrane prepared after a modified heparin method of Bornens and Courvalin. Electron micrographs and scanning micrographs helped to establish the characterization of closed vesicles and intact nuclei. With the aid of (alpha-32P)-labeled, and of the (beta, gamma-32P)-labeled analogue, it was possible to demonstrate the incorporation of the nucleotide into a few protein regions of the nuclear membrane disc electrophoresis pattern. PMID:6183117

Kondor-Koch, C; Riedel, N; Valentin, R; Fasold, H; Fischer, H

1982-10-01

361

Immunohistochemical characterization of cellular proliferation in small intestinal hyperplasia of rats with hepatic Strobilocercus fasciolaris infection.  

PubMed

Rats infected with the larvae of Taenia taeniaeformis harbour the intermediate stage of the parasite Strobilocercus fasciolaris within the liver. Affected animals also develop gastric and intestinal hyperplasia. The pathogenesis of the gastric hyperplasia has been extensively investigated, but few studies have addressed the nature of the intestinal changes. This study characterizes the proliferation of small intestinal epithelial cells by immunohistochemical labelling for proliferating cell nuclear antigen (PCNA) and bromodeoxyuridine (BrdU) uptake. At 6 weeks post-infection (wpi) there was an increase in villous length but crypt depth was normal. At 9 wpi there was evidence of epithelial hyperplasia, increased villous length and crypt depth, and expansion of zones of epithelial proliferation. Immunohistochemical labelling indicated that an increase in the number of proliferating cells produced a greater number of progeny cells. Intestinal hyperplasia during experimental infection with T. taeniaeformis larvae is likely to be related to the associated gastropathy, although the mechanisms underlying both changes remain undefined. PMID:18539293

Lagapa, J T; Oku, Y; Kamiya, M

2008-07-01

362

Characterization of cultured rat oligodendrocytes proliferating in a serum-free, chemically defined medium  

SciTech Connect

A serumless, chemically defined medium has been developed for the culture of oligodendrocytes isolated from primary neonatal rat cerebral cultures. Combined together, insulin, transferrin, and fibroblast growth factor synergistically induced an essentially homogeneous population (95-98%) of cells expressing glycerol-3-phosphate dehydrogenase activity to undergo cell division. Proliferating cells were characterized by several criteria: (i) ultrastructural analysis by transmission electron microscopy identified the cell type as an oligodendrocyte; (ii) biochemical assays showed expression of three oligodendrocyte biochemical markers, induction of both glycerol phosphate dehydrogenase and lactate dehydrogenase, and presence of 2',3'-cyclic nucleotide 3'-phosphodiesterase; and (iii) immunocytochemical staining showed cultures to be 95-98% positive for glycerol phosphate dehydrogenase, 90% for myelin basic protein, 60-70% for galactocerebroside, and 70% for A2B5.

Saneto, R.P.; de Vellis, J.

1985-05-01

363

Radiological, chemical and morphological characterizations of phosphate rock and phosphogypsum from phosphoric acid factories in SW Spain.  

PubMed

In this work, radiological, chemical, and also morphological characterization was performed in phosphate rock and phosphogypsum samples, in order to understand the behavior of toxic elements. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), gamma spectrometry and scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX). Our results show that the phosphate rock was mainly composed of fluorapatite, calcite, perovskite, quartz, magnetite, pyrite and kaolinite, whereas phosphogypsum only exhibited dihydrated calcium sulfate. The activity concentration of U-series radioisotopes in phosphate rock was around 1640 Bq/kg. (226)Ra and (210)Pb tend to be distributed into phosphogypsum by up to 80%, whereas the fraction of U-isotopes is 10%. The most abundant trace elements in phosphate rock were Sr, Cr, V, Zn, Y, Ni and Ba. Some elements, such as Ba, Cd, Cu, La, Pb, Se, Sr, Th and Y, were enriched in the phosphogypsum. This enrichment may be attributed to an additional input associated to the sulfuric acid used for the phosphoric acid production. Furthermore, results from SEM-EDX demonstrated that toxic elements are not distributed homogeneously into phosphogypsum. Most of these elements are concentrated in particles <20 microm of high porosity, and could be easily mobilized by leaching and/or erosion. PMID:20537794

Rentería-Villalobos, Marusia; Vioque, Ignacio; Mantero, Juan; Manjón, Guillermo

2010-09-15

364

Characterization of the major diazo-positive pigments in bile of homozygous Gunn rats  

PubMed Central

Bilinoid pigments in bile of homozygous Gunn rats (jj) were analysed either after formation of dipyrrolic ethyl anthranilate azo derivatives or as the unmodified parent tetrapyrroles. 1. T.l.c. of the azo derivatives revealed seven major unconjugated components which were structurally characterized by chemical tests, spectrophotometry and mass spectrometry. In addition, two minor components were identified as azodipyrrole (A+B)-glucoside and azodipyrrole (A+B)-?-d-glucuronide. 2. Extraction and t.l.c. of the tetrapyrrolic pigments showed 13 major yellow diazo-positive bands. Four of them, accounting for 59% of total diazo-positive material, were identified as unconjugated bilirubin-IX?, -IX?, -IX? and -IX?. A fifth band (16%) was characterized as a mixture of two isomeric monohydroxyl derivatives and another band (8%) as a dihydroxyl derivative of bilirubin-IX?. 3. Although unconjugated bilirubin-IX? constitutes one-third of total diazo-positive material in bile of our strain of Gunn rats, the daily amount excreted represented only about 3–4% of daily bilirubin production. 4. Phototherapy caused a 2.2-fold increase in the biliary output of diazo-positive bilinoids, but did not affect markedly their composition. However, an additional diazo-negative pigment, accounting for one-third of total yellow colour, was observed but was not identified. Mass-spectral data on two dipyrrolic azopigments have been deposited as Supplementary Publication SUP 50076 (3 pages) with the British Library Lending Division, Boston Spa, Wetherby, W. Yorkshire LS23 7BQ, U.K., from whom copies may be obtained on the terms given in Biochem. J. (1977) 161, 1. PMID:880230

Blanckaert, Norbert; Fevery, Johan; Heirwegh, Karel P. M.; Compernolle, Frans

1977-01-01

365

Characterization of metabotropic glutamate receptors in rat C6 glioma cells.  

PubMed

Metabotropic glutamate receptors in rat C6 glioma cells have been characterized by pharmacological and kinetic binding experiments, using both L-[3H]glutamate and [3H(+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid ([3H](+/-)-trans-ACPD) radioligands. Saturation experiments revealed a single binding site with a Kd = 1250 +/- 101 nM and Bmax = 12.1 +/- 1.8 pmol/mg protein when the assays were performed with L-[3H]glutamate as radioligand in the presence of AMPA, kainate, NMDA and DL-threo-beta-hydroxyaspartic acid. When [3H](+/-)-trans-ACPD was used as radioligand, the kinetic parameters obtained were Kd = 2605 +/- 1042 nM and Bmax = 13.66 +/- 5.01 pmol/mg protein. Pharmacological characterization indicated that specific binding of L-[3H]glutamate was sensitive to different agonists of mGlu receptors, showing a rank order of affinity L-glutamate > L-quisqualic acid > (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (trans-ACPD) > ibotenic acid > (2S, 'S,2'S)-2-(carboxycyclopropyl)glycine (L-CCG-I). Specific binding of L-[3H]glutamate to mGlu receptors is regulated by guanine nucleotides. Guanylyl imidodiphosphate (Gpp(NH)p) causes an affinity shift on the L-glutamate dose-response curve, increasing the IC50 value. These results support the evidence that metabotropic glutamate receptors are present in rat C6 glioma cells and they are coupled to a G-protein. PMID:9178659

Albasanz, J L; Ros, M; Martín, M

1997-05-12

366

Precancerous lesions and conditions of the prostate: from morphological and biological characterization to chemoprevention.  

PubMed

Prostatic intraepithelial neoplasia (PIN) is composed of dysplastic cells with a luminal cell phenotype, expressing the androgen receptor as well as prostate-specific antigen. PIN is characterized by progressive abnormalities of phenotype that are intermediate between normal prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of carcinogenesis. High-grade PIN is considered the most likely precursor of prostatic carcinoma, according to virtually all available evidence. Androgen deprivation decreases the prevalence and extent of PIN and the degree of capillary vascularization (e.g., angiogenesis) in the surrounding stroma via suppression of vascular endothelial growth factor production. Prostatic carcinoma is also likely to arise from precursor lesions other than high-grade PIN such as low-grade PIN, atypical adenomatous hyperplasia, malignancy-associated foci, and atrophy. PMID:12095942

Montironi, Rodolfo; Mazzucchelli, Roberta; Scarpelli, Marina

2002-06-01

367

Biochemical studies of rat liver Golgi apparatus. I. Isolation and preliminary characterization.  

PubMed

A method is described for the isolation of morphologically well-preserved Golgi apparatus from rat liver. The method is essentially the same as that of Morré et al. (Morré, D.J., Hamilton, R.L., Mollenhauser, H.H., Mahley, R.W., Cunningham, W.P., Cheetham, R.D., & Lequire, V.S. (1970) J. Cell Biol. 44, 484-491) except that mild cell disruption is achieved by means of a stainless-steel sieve. The average recoveries of protein and galactosyltransferase in the isolated fraction are about 6 mg from 10 g of perfused liver and about 35% from the homogenate, respectively. The preparation is virtually free from succinate-cytochrome c reductase, glucose-6-phosphatase, acid phosphatase, and 5'-nucleotidase. The Golgi fraction as well as its vesicular fragments is homogeneous upon isopycnic centrifugation in both sucrose and dextran density gradients. Their buoyant densities in sucrose are significantly higher than those in dextran, indicating that both forms of the organelle are closed systems which are impermeable to macromolecules. The galactosyltransferase activity of a freshly prepared Golgi fraction, measured with ovalbumin as galactosyl acceptor, is activated 26-fold by the addition of Triton X-100, whereas those of homogenized, sonicated, and aged preparations are only activated 2- to 4-fold. PMID:96108

Hino, Y; Asano, A; Sato, R; Shimizu, S

1978-04-01

368

Methods for assessing sperm motility, morphology, and counts in the rat, rabbit, and dog: A consensus report  

Microsoft Academic Search

Reproductive toxicity studies are increasingly including assessments of sperm parameters including motility, morphology, and counts. While these assessments can provide valuable information for the determination of potential reproductive toxicity, the methods for conducting the assessments have not been well developed in all laboratories and are continually evolving. The use of different methods in different laboratories makes comparison of data among

Jennifer Seed; Robert E. Chapin; Eric D. Clegg; Lori A. Dostal; Robert H. Foote; Mark E. Hurtt; Gary R. Klinefelter; Susan L. Makris; Sally D. Perreault; Steve Schrader; David Seyler; Robert Sprando; Kimberley A. Treinen; D. N. Rao Veeramachaneni; L. David Wise

1996-01-01

369

The effect of exercise and anabolic steroids on the mechanical properties and crimp morphology of the rat tendon  

Microsoft Academic Search

The administration of anabolic steroids is believed to be widespread among athletes, but convincing evi dence relating to the beneficial effect of such com pounds on collagenous structures of the locomotor system is not available. Since it has not been possible to analyze relevant human tissue, an animal model was used to investigate the change in particular mechanical and morphological

T. O. Wood; P. H. Cooke; A. E. Goodship

1988-01-01

370

Morphological evidence for a neurotensinergic periaqueductal gray-rostral ventromedial medulla-spinal dorsal horn descending pathway in rat  

PubMed Central

Neurotensin (NT) is an endogenous neuropeptide that exerts potent opioid-independent analgesic effects, most likely via the type 2 NT receptor (NTR2). Previous morphological and electrophysiological studies suggested that the NT-NTR2 system is primarily localized in structures that constitute the descending pain control pathway, such as the periaqueductal gray (PAG), the rostral ventromedial medulla (RVM), and the spinal dorsal horn (SDH). However, relevant morphological evidence for this neurotensinergic (NTergic) circuit is lacking. Thus, the aim of the present study was to morphologically elucidate the potential sites and connections in the NT-NTR2 system that are involved in the descending pain control pathway. Based on light and electron microscopy combined with anterograde and retrograde tracing, we found evidence that NTR2-immunoreactive (IR) neurons in the RVM receive NT-IR projections originating from the PAG; express NT, serotonin (5-HT), or both; and send projections that terminate in laminae I and II of the SDH. These results suggest that NTR2 may contribute to pain control by binding to NT in the PAG-RVM-SDH pathway. In conclusion, our data provide morphological evidence for an NTergic PAG-RVM-SDH pathway, implicating novel mechanisms of NT-induced analgesia. PMID:25346662

Wang, Jian; Zhang, Hua; Feng, Yu-Peng; Meng, Hua; Wu, Li-Ping; Wang, Wen; Li, Hui; Zhang, Ting; Zhang, Jin-Shan; Li, Yun-Qing

2014-01-01

371

Analysis of the effects of food and of digestive secretions on the small intestine of the rat. 1. Mucosal morphology and epithelial replacement.  

PubMed Central

A modified Roux-en-Y repositioning of rat small intestine was performed so that the proximal segment of bowel (A) received only bile and pancreastic secretions, the second (B) received food direct from the stomach, and these two segments drained into a third (C). Four to five weeks after operation, cell production was assessed by injection of vincristine into operated, sham-operated and unoperated rats, and counts of blocked metaphases were made on isolated microdissected crypts. Villus height, crypt depth, and the number of crypts per villus (crypt/villus ratio) were also measured. Most of segment A showed no significant differences from sham-operated intestine, although the normal proximo-distal gradient of villus height was abolished. At the distal end (near the anastomosis with segments B and C), crypt depth and cell production were increased. The villus height gradient in segment B was also abolished, although crypt depth and cell production were significantly increased, especially at the proximal end. Crypt/villus ratio was also increased. Segment C showed all the characteristics of small bowel promoted to a more proximal position: increased villus height, crypt depth and cell production. Increased crypt/villus ratio was also observed. These results are discussed in terms of the role of food and of digestive secretions in the control of mucosal morphology and epithelial replacement. PMID:1001979

Clarke, R M; Ecknauer, R; Feyerabend, G

1976-01-01

372

Morphological, molecular and functional differences of adult bone marrow- and adipose-derived stem cells isolated from rats of different ages  

SciTech Connect

Adult mesenchymal stem cells have self-renewal and multiple differentiation potentials, and play important roles in regenerative medicine. However, their use may be limited by senescence or age of the donor, leading to changes in stem cell functionality. We investigated morphological, molecular and functional differences between bone marrow-derived (MSC) and adipose-derived (ASC) stem cells isolated from neonatal, young and old rats compared to Schwann cells from the same animals. Immunocytochemistry, RT-PCR, proliferation assays, western blotting and transmission electron microscopy were used to investigate expression of senescence markers. Undifferentiated and differentiated ASC and MSC from animals of different ages expressed Notch-2 at similar levels; protein-38 and protein-53 were present in all groups of cells with a trend towards increased levels in cells from older animals compared to those from neonatal and young rats. Following co-culture with adult neuronal cells, dMSC and dASC from animals of all ages elicited robust neurite outgrowth. Mitotracker{sup Registered-Sign} staining was consistent with ultrastructural changes seen in the mitochondria of cells from old rats, indicative of senescence. In conclusion, this study showed that although the cells from aged animals expressed markers of senescence, aged MSC and ASC differentiated into SC-like cells still retain potential to support axon regeneration. -- Highlights: Black-Right-Pointing-Pointer Aged MSC and ASC differentiated into Schwann-like cells support axon regeneration. Black-Right-Pointing-Pointer p53 expression does not appreciably influence the biology of Schwann or stem cells. Black-Right-Pointing-Pointer Notch 2 expression was similar in cells derived from animals of different ages. Black-Right-Pointing-Pointer Proliferation rates of dMSC varied little over time or with animal age.

Mantovani, Cristina [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom) [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden); Raimondo, Stefania [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy)] [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Haneef, Maryam S. [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom)] [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Geuna, Stefano [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy)] [Dipartimento di Scienze Cliniche e Biologiche, University of Turin (Italy); Terenghi, Giorgio [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom)] [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Shawcross, Susan G., E-mail: sue.shawcross@manchester.ac.uk [Blond McIndoe Laboratories, School of Biomedicine, The University of Manchester, Room 3,106 Stopford Building, Oxford Road, Manchester M13 9PT, Academic Health Science Centre, Faculty of Medicine and Human Sciences (United Kingdom); Wiberg, Mikael [Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden) [Department of Integrative Medical Biology and Surgical and Perioperative Science, Umea University, Umea (Sweden); Department of Surgical and Perioperative Science, Umea University, Umea (Sweden)

2012-10-01

373

Effects of rofecoxib, a selective cyclooxygenase-2 inhibitor, on endothelial dysfunction, lipid peroxidation, and hepatocyte morphology in rats with sepsis-induced liver damage  

PubMed Central

Background Sepsis remains a difficult problem for clinicians, with its systemic effects and high morbidity and mortality rates. The roles of oxidative stress, endothelial dysfunction, and lipid peroxidation in sepsis-induced organ damage are being investigated. Objective The aim of this study was to investigate the effects of selective cyclooxygenase (COX)-2 inhibition on tissue lipid peroxidation, endothelial dysfunction, and hepatic cell morphology in a rat model of sepsis. Methods Thirty rats with sepsis induced by cecal ligation and puncture were divided equally into 3 groups: treatment group (rofecoxib 1 mg/kg PO), control group (saline 1 mL PO), and sham group (sham surgery only). All the rats were sacrificed 1 day after sepsis induction. The livers were removed using a median laparotomy for histopathologic and biochemical analysis. Results Histomorphologic hepatic damage and lipid peroxidation were significantly reduced in the rofecoxib treatment group compared with the control group (P < 0.05 and P = 0.001, respectively). Endothelial nitric oxide synthase and inducible nitric oxide synthase staining of liver samples was statistically significantly reduced in the treatment group compared with the control group (both, P < 0.001). The hepatic nitric oxide level and malonyldialdehyde activity decreased significantly (P < 0.001 and P = 0.001, respectively) in the rofecoxib group compared with the control group. Hepatic myeloperoxidase activity was similar between the treatment and control groups. Conclusion Further investigation of selective COX-2 inhibition as an alternate therapeutic choice for sepsis-induced hepatic damage should be considered. PMID:24672083

Kara, Eray; Var, Ahmet; Vatansever, Seda; Cilaker, Serap; Kaya, Yavuz; Co?kun, Teoman

2004-01-01

374

The effect of recombinant adeno-associated virus-adiponectin (rAAV2/1-Acrp30) on glycolipid dysmetabolism and liver morphology in diabetic rats.  

PubMed

Adiponectin is an adipocytokine derived from adipocytes with insulin resistance-improving and anti-inflammatory activities. The level of Adiponectin is decreased in obesity, insulin resistance and Type 2 diabetes mellitus. The administration of recombinant adiponectin has been shown to improve hyperglycemia and insulin resistance in diabetic mice. Therefore, we investigated the effects of recombinant adeno-associated virus-adiponectin (rAAV2/1-Acrp30) on the glycolipid profile and liver morphology in streptozotocin-induced diabetic rats. Animals were fed a high-fat/high-glucose diet for 4weeks and diabetes induced by intraperitoneal administration of streptozotocin. The animals were divided randomly into four groups: diabetes control group, rAAV2/1-Acrp30 treatment group, vacuity virus group, and normal control group. Compared with diabetic rats and those in the vacuity virus group, animals treated with rAAV2/1-Acrp30 exhibited significantly lower values for glycaemic and lipidic profiles, and significantly higher levels of HDL. Although APN expression increased in the liver tissue, serum levels were not significantly increased. However, the rAAV2/1-Acrp30 treated animals showed amelioration of hepatic disease, accompanied by marked reduction in the expression of NF-?Bp65 and I?B?. The results suggest that rAAV2/1-Acrp30 ameliorates glycolipid dysmetabolism and hepatic disease in streptozotocin-induced diabetic rats. These observations indicate that the function of rAAV2/1-Acrp30 is mediated by downregulated expression of NF-?Bp65 and I?B?. PMID:25019654

Long, Wen; Hui Ju, Zhong; Fan, Zhang; Jing, Wang; Qiong, Li

2014-09-15

375

Dark cell change of the cerebellar Purkinje cells induced by terbutaline under transient disruption of the blood-brain barrier in adult rats: morphological evaluation.  

PubMed

This study aimed to establish a cerebellar degeneration animal model and to characterize the dark cell change of Purkinje cells. We hypothesized that terbutaline, a ?2-adrenoceptor agonist, induces cerebellar degeneration not only in neonatal rats, but also in adult rats. Nine-week-old adult male Sprague-Dawley rats were anesthetized and infused with 25% mannitol via the left common carotid artery. Thirty seconds later, terbutaline was infused via the same artery. Dark-stained Purkinje cells were observed in the entire cerebellum on day 3. Prominent Bergmann glial cells accompanied by swelling of the glial processes were present, and were closely associated with the dark-stained Purkinje cells. These findings were found continuously throughout day 30. Ultrastructurally, dilated Golgi vesicles and/or endoplasmic reticulum and large lamella bodies were present in both severely changed and slightly changed Purkinje cells. Bergmann glial cells in the area of synaptic contacts of the severely changed Purkinje cells showed swelling. The Bergmann glial process in close contact with the slightly changed Purkinje cell dendrite in molecular layer showed slight swelling, and large lamella bodies in the dendrite were observed close to the dendritic spines. These findings may suggest that terbutaline induced a failure of Bergmann glial cell and resulted in dark cell degeneration of the Purkinje cells due to glutamate excitotoxicity. PMID:21618259

Yamada, Naoaki; Sasaki, Satoshi; Ishii, Hiroyuki; Sato, Junko; Kanno, Takeshi; Wako, Yumi; Tsuchitani, Minoru

2012-10-01

376

Synthesis and Characterization of Ordered Mesoporous Silica with Controlled Macroscopic Morphology for Membrane Applications  

NASA Astrophysics Data System (ADS)

Ordered mesoporous materials have tunable pore sizes between 2 and 50 nm and are characterized by ordered pore structures and high surface areas (~1000 m2/g). This makes them particularly favorable for a number of membrane applications such as protein separation, polymer extrusion, nanowire fabrication and membrane reactors. These membranes can be fabricated as top-layers on macroporous supports or as embedded membranes in a dense matrix. The first part of the work deals with the hydrothermal synthesis and water-vapor/oxygen separation properties of supported MCM-48 and a new Al-MCM-48 type membrane for potential use in air conditioning systems. Knudsen-type permeation is observed in these membranes. The combined effect of capillary condensation and the aluminosilicate matrix resulted in the highest separation factor (142) in Al-MCM-48 membranes, with a water vapor permeance of 6x10 -8mol/m2·Pa·s. The second part focuses on synthesis of embedded mesoporous silica membranes with helically ordered pores by a novel Counter Diffusion Self-Assembly (CDSA) method. This method is an extension of the interfacial synthesis method for fiber synthesis using tetrabutylorthosilicate (TBOS) and cetyltrimethylammonium bromide (CTAB) as the silica source and surfactant respectively. The initial part of this study determined the effect of TBOS height and humidity on fiber formation. From this study, the range of TBOS heights for best microscopic and macroscopic ordering were established. Next, the CDSA method was used to successfully synthesize membranes, which were characterized to have good support plugging and an ordered pore structure. Factors that influence membrane synthesis and plug microstructure were determined. SEM studies revealed the presence of gaps between the plugs and support pores, which occur due to shrinking of the plug on drying. Development of a novel liquid deposition method to seal these defects constituted the last part of this work. Post sealing, excess silica was removed by etching with hydrofluoric acid. Membrane quality was evaluated at each step using SEM and gas permeation measurements. After surfactant removal by liquid extraction, the membranes exhibited an O2 permeance of 1.65x10-6mol/m2.Pa.s and He/O2 selectivity of 3.30. The successful synthesis of this membrane is an exciting new development in the area of ordered mesoporous membrane technology.

Stohlman, Olive R.

2011-12-01

377

Morphological, molecular and biochemical characterization of astaxanthin-producing green microalga Haematococcus sp. KORDI03 (Haematococcaceae, Chlorophyta) isolated from Korea.  

PubMed

A unicellular red microalga was isolated from environmental freshwater in Korea, and its morphological, molecular and biochemical properties were characterized, respectively. Morphological analysis revealed that the isolate was biflagellated unicellular green microalga with forming a non-motile, thick-walled palmelloid or red aplanospore. To determine the taxonomical position of the isolate, 18S rRNA and rbcL genes were sequenced and its phylogenetic analysis was conducted, and the results revealed that the isolate was clustered together with other related Haematococcus strains with showing differences in the rbcL gene. Therefore, the isolated microalga was classified into the genus Haematococcus, and finally designated as Haematococcus sp. KORDI03. The microalgae could be cultivated in various culture media under broad range of pH and temperature conditions. Compositions of the cellular components of the microalgae were further analyzed, and its protein, carbohydrate and lipid compositions were estimated to be 21.1±0.2 %, 48.8±1.8 % and 22.2±0.9 %, respectively. In additions, D-glucose and D-mannose were found as the dominant mono-saccharides in the isolate, and its amino acids were mainly composed of aspartic-acid, glutamic acid, alanine and leucine. Moreover, several polyunsaturated fatty acids (PUFAs) comprised about 80% of the total fatty acids in Haematococcus sp. KORDI03, and its astaxanthin content in red aplanospore was estimated to be 1.8% of the dry cell weight. To our knowledge, this is the first report of Haematococcus sp. isolated from Korea, and the isolated strain will have a potential for bioresource production in microalgal industry. PMID:25381742

Kim, Ji Hyung; Affan, Abu; Jang, Jiyi; Kang, Mee-Hye; Ko, Ah-Ra; Jeon, Seon-Mi; Oh, Chulhong; Heo, Soo-Jin; Lee, Youn-Ho; Ju, Se-Jong; Kang, Do-Hyung

2014-11-10

378

Morphology and molecular characterization of the epiphytic dinoflagellate Prorocentrum cf. rhathymum in temperate waters off Jeju Island, Korea  

NASA Astrophysics Data System (ADS)

Prorocentrum spp. are planktonic and/or benthic species. Benthic Prorocentrum species are of primary concern to scientists and the public because some of them are toxic. We established clonal cultures of 3 strains of Prorocentrum species that were collected from the thalli of a macroalga in the coastal waters off Jeju Island, located at the southern end of Korea. The Korean strains of P. cf. rhathymum, which are morphologically almost identical to the Virgin Island strain of P. rhathymum, were different from P. mexicanum because the former dinoflagellate has one simple collar-like spine in the periflagellar area, while the latter dinoflagellate has a 2- or 3-horned spine. In addition, the sequences of the small subunit (SSU) rDNA of the Korean strains were identical to those of the Malaysian and Floridian strains of P. rhathymum, while the sequences of the large subunit (LSU) rDNA of the Korean strains were 0.1-0.9% different from those of the Iranian and Malaysian strains of P. rhathymum. In phylogenetic trees based on the SSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Malaysian and Floridian strains of P. rhathymum and the Vietnamese and Polynesian strains of P. mexicanum. However, in phylogenetic trees based on the LSU rDNA sequences, the Korean strains of P. rhathymum formed a clade with the Iranian strain of P. rhathymum and the Spanish and Mexican strains of P. mexicanum. Therefore, the molecular characterization of the Korean strains does not allow us to clearly classify them as P. rhathymum, nor P. mexicanum, although their morphology has so far been reported to be closer to that of P. rhathymum than P. mexicanum and thus we designated them as P. cf. rhathymum.

Lim, An Suk; Jeong, Hae Jin; Jang, Tae Young; Kang, Nam Seon; Lee, Sung Yeon; Yoo, Yeong Du; Kim, Hyung Seop

2013-03-01

379

Metabolic and morphological alterations induced by proteolysis-inducing factor from Walker tumour-bearing rats in C2C12 myotubes  

PubMed Central

Background Patients with advanced cancer suffer from cachexia, which is characterised by a marked weight loss, and is invariably associated with the presence of tumoral and humoral factors which are mainly responsible for the depletion of fat stores and muscular tissue. Methods In this work, we used cytotoxicity and enzymatic assays and morphological analysis to examine the effects of a proteolysis-inducing factor (PIF)-like molecule purified from ascitic fluid of Walker tumour-bearing rats (WF), which has been suggested to be responsible for muscle atrophy, on cultured C2C12 muscle cells. Results WF decreased the viability of C2C12 myotubes, especially at concentrations of 20–25 ?g.mL-1. There was an increase in the content of the pro-oxidant malondialdehyde, and a decrease in antioxidant enzyme activity. Myotubes protein synthesis decreased and protein degradation increased together with an enhanced in the chymotrypsin-like enzyme activity, a measure of functional proteasome activity, after treatment with WF. Morphological alterations such as cell retraction and the presence of numerous cells in suspension were observed, particularly at high WF concentrations. Conclusion These results indicate that WF has similar effects to those of proteolysis-inducing factor, but is less potent than the latter. Further studies are required to determine the precise role of WF in this experimental model. PMID:18226207

Yano, Claudia L; Ventrucci, Gislaine; Field, William N; Tisdale, Michael J; Gomes-Marcondes, Maria Cristina C

2008-01-01

380

Four cell types with distinctive membrane properties and morphologies in lamina I of the spinal dorsal horn of the adult rat  

PubMed Central

Lamina I of the spinal dorsal horn plays an important role in the processing and relay of nociceptive information. Signal processing depends, in part, on neuronal membrane properties. Intrinsic membrane properties of lamina I neurons were therefore investigated using whole cell patch clamp recordings in a slice preparation of adult rat spinal cord. Based on responses to somatic current injection, four cell types were identified: tonic, which fire comparatively slowly but continuously throughout stimulation; phasic, which fire a high frequency burst of variable duration; delayed onset, which fire irregularly and with a marked delay to the first spike; and single spike, which typically fire only one action potential even when strongly depolarised. Classification by spiking pattern was further refined by identification of characteristic stimulus-response curves and quantification of several response parameters. Objectivity of the classification was confirmed by cluster analysis. Responses to stimulus trains and synaptic input as well as the kinetics of spontaneous synaptic events revealed differences in the signal processing characteristics of the cell types: tonic and delayed onset cells appeared to act predominantly as integrators whereas phasic and single spike cells acted as coincidence detectors. Intracellular labelling revealed a significant correlation between morphological and physiological cell types: tonic cells were typically fusiform, phasic cells were pyramidal, and delayed onset and single spike cells were multipolar. Thus, there are multiple physiological cells types in lamina I with specific morphological correlates and distinctive signal processing characteristics that confer significant differences in the transduction of input into spike trains. PMID:11897852

Prescott, Steven A; Koninck, Yves De

2002-01-01