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1

Morphologic and functional characterization of caveolae in rat liver hepatocytes  

Microsoft Academic Search

Caveolae are small pits on the plasma membrane found in several, if not all, differentiated cells. They are involved in potocytosis, endocytosis, transcytosis, membrane trafficking, and signal transduction. Although caveolin has recently been identified in subcellular fractions from rat liver there is no clear-cut morphologic evidence for the presence of prototypical caveolae on the surface of hepatocytes. In this study

Maria Calvo; Francesc Tebar; Carmen Lopez-Iglesias; Carlos Enrich

2001-01-01

2

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

3

Morphologic characterization of spontaneous nervous system tumors in mice and rats.  

PubMed

Spontaneous rodent nervous system tumors, in comparison to those of man, are less well differentiated. Among the central nervous system (CNS) tumors, the "embryonic" forms (medulloblastoma, pineoblastoma) occur both in rodents and humans, whereas the human "adult" forms (gliomas, ependymomas, meningiomas) have fewer counterparts in rodents. In general, the incidence of spontaneous CNS tumors is higher in rats (>1%) than in mice (>0.001%). A characteristic rat CNS tumor is the granular cell tumor. Usually it is associated with the meninges, and most meningeal tumors in rats seem to be totally or at least partly composed of granular cells, which have eosinophilic granular cytoplasm, are periodic acid-Schiff reaction (PAS)-positive, and contain lysosomes. Such tumors are frequently found on the cerebellar surface or at the brain basis. Rat astrocytomas are diffuse, frequently multifocal, and they invade perivascular spaces and meninges. The neoplastic cells with round to oval nuclei and indistinct cytoplasm grow around preexisting neurons, producing satellitosis. In large tumors, there are necrotic areas surrounded by palisading cells. Extensive damage of brain tissue is associated with the presence of scavenger cells that react positively with histiocytic/macrophage markers. The neoplastic astrocytes do not stain positively for glial fibrillary acidic protein; they probably represent an immature phenotype. In contrast to neoplastic oligodendroglia, they bind the lectin RCA-1. Astrocytomas are frequently located in the brain stem, especially the basal ganglia. Rat oligodendroglial tumors are well circumscribed and frequently grow in the walls of brain ventricles. Their cells have water-clear cytoplasm and round, dark-staining nuclei. Atypical vascular endothelial proliferation occurs, especially at the tumor periphery. Occasionally in the oligodendrogliomas, primitive glial elements with large nuclei occur in the form of cell groups that form rows and circles. Primitive neuroectodermal tumors of rats, such as pineal tumors or medulloblastomas, appear to have features similar to those found in man. In mice, the meningeal tumors are mostly devoid of granular cells and the astrocytomas are similar to those occurring in rats, whereas spontaneous oligodendrogliomas are observed extremely rarely. Tumorlike lesions, such as lipomatous hamartomas or epidermoid cysts, are occasionally encountered in the mouse CNS. It is suggested that we classify rodent CNS lesions as "low grade" and "high grade" rather than as "benign" and "malignant." The size of CNS tumors is generally related to their malignancy. Tumors of the peripheral nervous system are schwannomas and neurofibromas or neurofibrosarcomas consisting of Schwann cells, fibroblasts, and perineural cells. Well-differentiated schwannomas are characterized by S-100 positivity and the presence of basement membrane. They show either Antoni A pattern with fusiform palisading cells or Antoni B pattern, which is sparsely cellular and has a clear matrix. The rat develops specific forms of schwannomas in the areas of the submandibular salivary gland, the external ear, the orbit, and the endocardium. Spontaneous ganglioneuromas occur in the rat adrenal medulla or thyroid gland. Compared to experimentally induced neoplasms, the spontaneous tumors of the rodent nervous system are poor and impractical models of human disease, although they may serve as general indicators of the carcinogenic potential of tested chemicals. PMID:10669006

Krinke, G J; Kaufmann, W; Mahrous, A T; Schaetti, P

2000-01-01

4

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

5

CHARACTERIZATION OF THE (rnunz) NUDE RAT. MORPHOLOGICAL CHARACTERISTICS OF THE LYMPHOID SYSTEM  

Microsoft Academic Search

A nude mutant (rnunz) arose spontaneously in a colony of Wistar albino rats (the wild-type strain) in Wellington, New Zealand. On gross examination no thymus could be found in the mediastina of young animals, whereas in older mutants lobules of fatty tissue mimicked the appearance of the thymus of the wild-type strain. Lymph nodes from the rnunz strain showed a

Anthony Douglas-Jones; Jan Nelson; Vernon Jansen; Thomas Miller

1981-01-01

6

Morphological and electrophysiological characterization of layer III cells of the medial entorhinal cortex of the rat  

Microsoft Academic Search

Entorhinal cortex layer III cells send their axons into hippocampal area CA1, forming the less well studied branch of the perforant path. Using electrophysiological and morphological techniques within a slice preparation, we can classify medial entorhinal cortex layer III cells into four different types. Type 1 and 2 cells were projection cells. Type 1 cells fired regularly and possessed high

T Gloveli; D Schmitz; R. M Empson; T Dugladze; U Heinemann

1997-01-01

7

Isolation and characterization of epithelial and myogenic cells by "fishing" for the morphologically distinct cell types in rat primary periodontal ligament cultures.  

PubMed

The periodontal ligament (PDL) contains various cell populations and plays a central role in the maintenance, repair, and regeneration of the periodontium, i.e., tooth-supporting structures. Because primary cells isolated from PDL tissue are heterogeneous, the establishment of an effective isolation method for cells of interest is desired. In the present study, two morphologically distinct cell types were identified in confluent primary cultures derived from rat PDL. To isolate these cell populations, a small piece of filter paper soaked with trypsin-EDTA was placed directly onto the target cell population, enabling the cells to detach from the culture dish. The filter papers were then transferred into fresh culture dishes to establish outgrowth cultures; these two steps constitute the "cell fishing" method. The "fished" cell types were propagated and subcultured for further analyses. In morphological evaluation, immunocytochemical analyses, and reverse transcription-polymerase chain reaction, the isolated cells exhibited a polygonal appearance or a mono- or multinucleated appearance, with a high cytoplasm-to-nucleus ratio, leading to their being characterized as epithelial or myogenic cell populations, respectively. Surprisingly, a notable proportion of the multinuclear cells in the primary and subsequent isolated cultures demonstrated dramatic, spontaneous contractions, a feature typical of skeletal muscle cells. Finally, the isolated cell populations maintained a normal karyotype with a diploid chromosomal number. These results demonstrated that physiological epithelial and skeletal muscle cells can be obtained from primary PDL cultures without artificial induction using growth factors or chemicals, and can be propagated as individual lineage-committed cell populations; the populations consisted of differentiated and progenitor cells that maintained chromosomal stability. This simple, classical culture procedure provides new insights into the biological properties of PDL cells, which are potentially important for the differentiation of tissue or somatic stem cells and for the development of future cell-based therapies for dental and muscular diseases. PMID:23649106

Tominaga, Noriko; Nakahara, Taka; Nasu, Masanori; Satoh, Tazuko

2013-02-01

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 microcellular carbon foams  

SciTech Connect

Low-density, microcellular carbon foams have been prepared by the high temperature degradation of polyacrylonitrile (PAN) foams in an inert atmosphere. The PAN foams are first prepared by controlled phase separation of PAN solutions followed by solvent removal. Some possible applications for low-density, microcellular carbon foams are: catalyst supports, adsorbents, porous electrodes, high temperature structural insulation, and in the fabrication of inertial confinement fusion targets. To effectively design and use these carbon foams, it is necessary to characterize their morphology. In this paper, we describe two techniques which are well suited to characterize microcellular carbon foam morphologies. 3 refs., 1 fig.

Aubert, J.H.; Sylwester, A.P.

1989-01-01

11

Chronological and morphological study of heart development in the rat.  

PubMed

Adult and embryonic laboratory rats have been used as a mammalian model organism in biomedical research, descriptive and experimental cardiac embryology, and experimental teratology. There have been, however, considerable variations and discrepancies concerning the developmental staging of the rat embryo in the reported literature, which have resulted in several controversies and inconsistencies. Therefore, we carried out a careful anatomical and histological study of rat cardiac morphogenesis from the premorphogenetic period to the mature heart in a newborn pup. A correlation between the chronology and morphological features of the heart and embryo or newborn was made. We provide a simple and comprehensive guide relating the developmental timing and fate of the embryonic components of the heart and their morphological changes in the rat based on in vivo labeling studies in the chick. We also compare the timing of heart development in rats, humans, and mice. PMID:22715162

Marcela, Salazar García; Cristina, Revilla Monsalve María; Angel, Palomino Garibay Miguel; Manuel, Arteaga Martínez; Sofía, Díaz-Cintra; Patricia, De La Rosa-Santander; Bladimir, Roque-Ramírez; Concepción, Sánchez Gómez

2012-08-01

12

Social Structure Predicts Genital Morphology in African Mole-Rats  

Microsoft Academic Search

BackgroundAfrican mole-rats (Bathyergidae, Rodentia) exhibit a wide range of social structures, from solitary to eusocial. We previously found a lack of sex differences in the external genitalia and morphology of the perineal muscles associated with the phallus in the eusocial naked mole-rat. This was quite surprising, as the external genitalia and perineal muscles are sexually dimorphic in all other mammals

Marianne L. Seney; Diane A. Kelly; Bruce D. Goldman; Radim Sumbera; Nancy G. Forger; Anna Dornhaus

2009-01-01

13

The effects of permethrin on rat ovarian tissue morphology.  

PubMed

All organisms are exposed to chemical agents during their lifetime. One of these agents is a pesticide that is used as fly killer. In this study we investigated the effects of permethrin on rat ovaries using light and electron microscopy. We used 24 Wistar albino female rats and divided them into 3 groups. Dosages 20 and 40mg/kg/day permethrin were administered by gavage for 14 days. Normal saline was given to control rats. After treatment, ovarian tissues were collected and prepared for light and electron microscopy evaluation. Negative effects of permethrin were detected on follicular and corpus luteum cell morphology in a dose dependent manner when compared with the control group. Picnotic cellular appearance and condensed chromatin were detected as evidence of apoptotic cell death. Furthermore, degenerative changes were seen in the ultrastructure of mitochondria and endoplasmic reticulum. Thus, these findings suggested that permethrin caused degenerative effects on ovarian morphology in a dose dependent manner. PMID:25665982

Kotil, Tu?ba; Yön, Nazan Deniz

2015-03-01

14

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

15

High-intensity exercise may compromise renal morphology in rats.  

PubMed

We investigated the renal effects of a high-intensity exercise (HIE) program based on strength training. 20 Wistar rats were randomly assigned to 2 experimental groups performing HIE or control over 12 weeks. Urinary volume, pH, citrate and calcium, and plasma urea, total proteins, creatinine, albumin, lactate dehydrogenase, creatine kinase (CK), calcium, magnesium, corticosterone and testosterone were measured. We also studied renal morphology with the Fibrosis HR(®) software. Plasma urea and CK concentrations were higher in the HIE compared to the control group (p < 0.05), whereas plasma creatinine was lower (p < 0.01). Plasma corticosterone was higher (p < 0.05) and testosterone lower (p < 0.01) in the HIE group. Except for the higher urinary volume found in the HIE group (p < 0.05), no differences between groups were observed in the rest of urinary parameters analyzed. Renal interstitial connective tissue was ~30% higher in the HIE group (p < 0.05). Glomerular tufts and mesangial areas were also higher in the HIE group (all, p < 0.05). No differences between groups were observed in the glomerular area. Overall, HIE promoted a worse morphological renal profile that might be associated with a higher risk for incidence of kidney disease in the long-term. The stress induced by the type of exercise performed could be on the basis of this worse morphological renal status. PMID:24424961

Aparicio, V A; Tassi, M; Nebot, E; Camiletti-Moirón, D; Ortega, E; Porres, J M; Aranda, P

2014-07-01

16

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

17

Postnatal morphology and functional capacity of the kidney following prenatal treatment with dinoseb in rats  

Microsoft Academic Search

Dinoseb has produced alterations that are suggestive of renal damage In mice and rats. Therefore it was of interest to determine the postnatal morphology and functional capacity of the kidney following prenatal treatment with dinoseb in rats. Fetal and neonatal rats treated with dinoseb on gestational d 10–12 had dilated renal pelves and ureters. Kidneys had dilated tubules and excessive

K. M. McCormack; A. Abuelgasim; V. L. Sanger; J. B. Hook

1980-01-01

18

Characterizing morphology in bulk heterojunction organic photovoltaic systems  

SciTech Connect

Organic semiconductors are an alternative to inorganic materials in solar cell applications. While the efficiencies of organic photovoltaics (OPVs) have been improving rapidly, they are currently below that required for widespread power generation. OPV performance is sensitive to the nanoscale texture, or film morphology, in the photovoltaic active layer, particularly in bulk heterojunction (BHJ) devices, and characterizing morphology across many length scales is currently a major experimental challenge. Here, we discuss several different experimental approaches for characterizing morphology in BHJ systems. These include techniques ranging from X-ray diffraction and spectroscopy to electron microscopy and scanning probe microscopy. These methods provide complementary information to guide future materials design and device optimization efforts.

Giridharagopal, Rajiv; Ginger, David S.

2010-01-01

19

Neurotransmitter-Specific Synaptosomes in Rat Corpus Striatum: Morphological Variations*  

PubMed Central

This communication describes ultrastructural variations among synaptosomal fractions isolated from the corpus striatum of the rat by incomplete equilibrium sedimentation in sucrose density gradients, and attempts to relate the variations to neurotransmitter-specific synaptosomes. The concentration of synaptosomes in each fraction of the density gradient was found to be correlated with the concentration of potassium, a marker for cytoplasm occluded within synaptosomes. Monoamine oxidase activity was found to be correlated with the incidence of free mitochondria in the gradients. Synaptosomes from denser gradient fractions showed a markedly increased frequency of adherent postsynaptic elements and intraterminal mitochondria. These denser gradient fractions were rich in synaptosomes containing norepinephrine, dopamine, serotonin, and acetylcholine, while synaptosomes in lighter portions of the gradients were rich in ?-aminobutyric acid and other amino acids. These data suggest that significant morphological variations may exist among different neurotransmitter-specific nerve terminals in the brain. Images PMID:4395685

Gfeller, Eduard; Kuhar, Michael J.; Snyder, Solomon H.

1971-01-01

20

Morphology of respiratory tract lesions in rats exposed to radon progeny  

SciTech Connect

We will discuss the morphologic features of lesions in the respiratory tract of rats exposed to radon and radon progeny. Groups of male Wister rats were exposed to from 10 to 1000 working levels (WL) of radon progeny in the presence of less than 1 to about 15 mg m{sup {minus}3} uranium ore dust. Cumulative exposures ranged from 20 to approximately 10,000 working level months (WLM). Higher exposure levels produced radiation pneumonitis characterized by interstitial fibrosis, associated with alveolar epithelial cell hyperplasia and accumulations of alveolar macrophages containing phagocytosed uranium ore dust. Nodular fibrosis and alveolar proteinosis were correlated with deposits of uranium ore dust. Vesicular emphysema also occurred at higher exposure levels. Pulmonary adenomatosis appeared to be a preneoplastic lesion; it was composed of nodular proliferation of bronchioloalveolar epithelium without disruption of the general architecture of the parenchyma. At exposure levels where rats lived longer than 1 y, lung tumors and a few tumors of the nasal cavity developed. The principal lung tumors were pulmonary adenomas, bronchioloalveolar carcinomas, papillary adenocarcinomas, epidermoid carcinomas, and adenosquamous carcinomas. Occasionally, malignant mesotheliomas and sarcomas were also present. The malignant lung tumors were characterized by invasion and occasionally metastasized to regional lymph nodes. Lower exposure rates produced more tumors, generally of different histologic types, and more fatal tumors than higher exposure rates. The similarity to relationships of human radon progeny exposure as far as incidence and types of lung tumors establish the validity of this animal model for studying radon carcinogenesis in humans.

Dagle, G.E.; Cross, F.T.; Gies, R.A. [Pacific Northwest Lab., Richland, WA (United States)

1992-12-31

21

Morphological analysis of rat ureteric terminal arterioles in situ.  

PubMed

Confocal imaging of Fluo-4, Propidium iodide, and di-8-Anepps loaded ureter were used to study the morphology of terminal arterioles with an inner diameter <50 ?m in intact rat ureter. Optical sectioning showed that the muscle coat of the terminal arterioles consisted of a monolayer of highly curved smooth muscle cells which run circumferentially around the endothelium. This technique allowed not only to measure the inner diameter of the terminal arterioles but also to define the orientation and number of revolutions an individual smooth muscle cell made around the endothelium. We measured thickness, width, length, and morphological profile of the myocytes and endothelial cells. Propidium iodide staining showed nuclei of individual cells by continuous imaging at high resolution in serial optical sections. Conventional haematoxylin-eosin, Masson's tri-chrome staining, and transmission electron microscopy were also used in this study to compare the measurements obtained from live confocal imaging with histological standard methods. Parameters obtained from live imaging were significantly different. This technique of live staining allowed measuring the cellular and nuclear dimensions of the terminal arterioles in their natural environment which are important in studying the effects of vascular disease or aging on vascular structure. PMID:23450700

Mumtaz, Sadaf

2013-06-01

22

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

23

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

24

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

25

Maze learning and morphology of frontal cortex in adult and aged basal forebrain-lesioned rats  

Microsoft Academic Search

Maze performance and morphology of frontal cortex were assessed in young adult, middle-aged, and aged rats with and without lesions of the nucleus basalis magnocellularis. Although maze performance did not vary with age, neuron number and the thickness of superficial laminae were reduced in aged rats. Lamina II-IH neurons were hypertrophied in middle-aged rats relative to both younger and older

Cara L. Wellman; Sheree F. Logue; Dale R. Sengelaub

1995-01-01

26

Teratogenic effect of isotretinoin on the morphology and palate development in rat fetuses  

Microsoft Academic Search

The effect of isotretinoin currently used in dermatological treatments was investigated on the morphology and palate development during organogenesis in rat fetuses. This was in an attempt to evaluate the morphological implications associated with isotretinoin consumption. The animals were randomly divided into groups: A, B and C. Group A was further divided into subgroups: A1 and A2 and administered orally

S. A. Jimoh; Komolafe A. O

27

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

28

Social status and sex effects on neural morphology in Damaraland mole-rats, Fukomys damarensis.  

PubMed

We previously reported that in a eusocial rodent, the naked mole-rat (Heterocephalus glaber), traditional neural sex differences were absent; instead, neural dimorphisms were associated with breeding status. Here we examined the same neural regions previously studied in naked mole-rats in a second eusocial species, the Damaraland mole-rat (Fukomys damarensis). Damaraland mole-rats live in social groups with breeding restricted to a small number of animals. However, colony sizes are much smaller in Damaraland mole-rats than in naked mole-rats and there is consequently less reproductive skew. In this sense, Damaraland mole-rats may be considered intermediate in social organization between naked mole-rats and more traditional laboratory rodents. We report that, as in naked mole-rats, breeding Damaraland mole-rats have larger volumes of the principal nucleus of the bed nucleus of the stria terminalis and paraventricular nucleus of the hypothalamus than do subordinates, with no effect of sex on these measures. Thus, these structures may play special roles in breeders of eusocial species. However, in contrast to what was seen in naked mole-rats, we also found sex differences in Damaraland mole-rats: volume of the medial amygdala and motoneuron number in Onuf's nucleus were both greater in males than in females, with no significant effect of breeding status. Thus, both sex and breeding status influence neural morphology in Damaraland mole-rats. These findings are in accord with the observed sex differences in body weight and genitalia in Damaraland but not naked mole-rats. We hypothesize that the increased sexual dimorphism in Damaraland mole-rats relative to naked mole-rats is related to reduced reproductive skew. PMID:21701152

Anyan, Jeff J; Seney, Marianne L; Holley, Amanda; Bengston, Lynn; Goldman, Bruce D; Forger, Nancy G; Holmes, Melissa M

2011-01-01

29

Alloxan-Induced Diabetes Causes Morphological and Ultrastructural Changes in Rat Liver that Resemble the Natural History of Chronic Fatty Liver Disease in Humans  

PubMed Central

Purpose. This study evaluated the long-term effects of alloxan-induced diabetes in rat liver. Methods. Thirty nondiabetic control rats (NC) and 30 untreated diabetic (UD) rats were divided into three subgroups sacrificed after 6, 14, or 26 weeks. Clinical and laboratory parameters were assessed. Fresh liver weight and its relationship with body weight were obtained, and liver tissue was analyzed. Results. UD rats showed sustained hyperglycemia, high glycosylated hemoglobin, and low plasma insulin. High serum levels of AST and ALT were observed in UD rats after 2 weeks, but only ALT remained elevated throughout the experiment. Fresh liver weight was equal between NC and UD rats, but the fresh liver weight/body weight ratio was significantly higher in UD rats after 14 and 26 weeks. UD rats showed liver morphological changes characterized by hepatic sinusoidal enlargement and micro- and macrovesicular hepatocyte fatty degeneration with progressive liver structure loss, steatohepatitis, and periportal fibrosis. Ultrastructural changes of hepatocytes, such as a decrease in the number of intracytoplasmic organelles and degeneration of mitochondria, rough endoplasmic reticulum, and nuclei, were also observed. Conclusion. Alloxan-induced diabetes triggered liver morphological and ultrastructural changes that closely resembled human disease, ranging from steatosis to steatohepatitis and liver fibrosis. PMID:25789328

Cassettari, Lucas Langoni; Spadella, César Tadeu

2015-01-01

30

Characterization of the spatial variability of channel morphology  

USGS Publications Warehouse

The spatial variability of two fundamental morphological variables is investigated for rivers having a wide range of discharge (five orders of magnitude). The variables, water-surface width and average depth, were measured at 58 to 888 equally spaced cross-sections in channel links (river reaches between major tributaries). These measurements provide data to characterize the two-dimensional structure of a channel link which is the fundamental unit of a channel network. The morphological variables have nearly log-normal probability distributions. A general relation was determined which relates the means of the log-transformed variables to the logarithm of discharge similar to previously published downstream hydraulic geometry relations. The spatial variability of the variables is described by two properties: (1) the coefficient of variation which was nearly constant (0.13-0.42) over a wide range of discharge; and (2) the integral length scale in the downstream direction which was approximately equal to one to two mean channel widths. The joint probability distribution of the morphological variables in the downstream direction was modelled as a first-order, bivariate autoregressive process. This model accounted for up to 76 per cent of the total variance. The two-dimensional morphological variables can be scaled such that the channel width-depth process is independent of discharge. The scaling properties will be valuable to modellers of both basin and channel dynamics. Published in 2002 John Wiley and Sons, Ltd.

Moody, J.A.; Troutman, B.M.

2002-01-01

31

Characterization of rat cecum cellulolytic bacteria.  

PubMed

Cellulose-degrading bacteria previously isolated from the ceca of rats have been characterized and identified. The most commonly isolated type was rods identified as Bacteroides succinogenes. These bacteria fermented only cellulose (e.g., pebble-milled Whatman no. 1 filter paper), cellobiose, and in 43 of 47 strains, glucose, with succinic and acetic acids as the major products. The only organic growth factors found to be required by selected strains were p-aminobenzoic acid, cyanocobalamine, thiamine, and a straight-chain and a branched-chain volatile fatty acid. These vitamin requirements differ from those of rumen strains of B. succinogenes, indicating the rat strains may form a distinct subgroup within the species. The mole percent guanine plus cytosine was 45%, a value lower than those (48 to 51%) found for three rumen strains of B. succinogenes included in this study. Cellulolytic cocci were isolated less frequently than the rods and were identified as Rumminococcus flavefaciens. Most strains fermented only cellulose and cellobiose, and their major fermentation products were also succinic and acetic acids. Their required growth factors were not identified but were supplied by rumen fluid. PMID:7159086

Montgomery, L; Macy, J M

1982-12-01

32

Development of morphological and functional polarity in primary cultures of immature rat uterine epithelial cells  

PubMed Central

The present study describes a culture environment in which luminal epithelial cells isolated from immature rat uteri and cultured on a matrix-coated permeable surface, with separate apical and basal secretory compartments, proliferate to confluence. Subsequently the cells undergo a process of differentiation accompanied by progressive development of functional polarity. Ultrastructural and immunocytochemical evidence verifies the ability of these primary cultures to regain polar organization, separate membrane domains, and form functional tight junctions as demonstrated by the development of transepithelial resistance. The appearance of uvomorulin is restricted to the lateral cell surface. Coordinated indices of functional polarity that develop progressively in post-confluent cultures include the preferential uptake of [35S]methionine from the basal surface and a rise in uterine epithelial cell secretory activity characterized by a progressive preference for apical secretion. The time dependent development of polarity was characterized by differences in the protein profiles of the apical and basolateral secretory compartments. The maintenance of hormone responsiveness by the cultured cells was validated by the secretion of two proteins identified as secretory markers of estrogen response in the intact uterus. The technique of culturing the cells on a matrix-coated permeable surface with separate secretory compartments produces a uterine epithelial cell that morphologically and functionally resembles its in situ equivalent. The culture method and analytical approach used in this present study may be applied to primary cultures of a variety of natural epithelia, which have hitherto proven resistant to more conventional culture methodologies. PMID:3143736

1988-01-01

33

Extensive morphological and immunohistochemical characterization in myotubular myopathy  

PubMed Central

The X-linked myotubular myopathy (XLMTM) also called X-linked centronuclear myopathy is a rare congenital myopathy due to mutations in the MTM1 gene encoding myotubularin. The disease gives rise to a severe muscle weakness in males at birth. The main muscle morphological characteristics (significant number of small muscle fibers with centralized nuclei and type 1 fiber predominance) are usually documented, but the sequence of formation and maintenance of this particular morphological pattern has not been extensively characterized in humans. In this study, we perform a reevaluation of morphological changes in skeletal muscle biopsies in severe XLMTM. We correlate the pathologic features observed in the muscle biopsies of 15 newborns with MTM1-mutations according to the “adjusted-age” at the time of muscle biopsy, focusing on sequential analysis in the early period of the life (from 34 weeks of gestation to 3 months of age). We found a similar morphological pattern throughout the period analyzed; the proportion of myofibers with central nuclei was high in all muscle biopsies, independently of the muscle type, the age of the newborns at time of biopsy and the specific MTM1 mutation. We did not observe a period free of morphological abnormalities in human skeletal muscle as observed in myotubularin-deficient mouse models. In addition, this study demonstrated some features of delayed maturation of the muscle fibers without any increase in the number of satellite cells, associated with a marked disorganization of the muscle T-tubules and cytoskeletal network in the skeletal muscle fibers. PMID:24381816

Shichiji, Minobu; Biancalana, Valérie; Fardeau, Michel; Hogrel, Jean-Yves; Osawa, Makiko; Laporte, Jocelyn; Romero, Norma Beatriz

2013-01-01

34

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

35

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

36

Polarized light scattering technique for morphological characterization of waterborne pathogens  

NASA Astrophysics Data System (ADS)

We have recently developed an elliptically polarized light scattering (EPLS) technique to characterize the morphology of fine particles suspended in an optically non-absorbing medium such as water. This technique provides the size distribution, shape and agglomeration characteristics of suspended particles. This technique can be used to detect various types of biological pathogens such as bacteria, protozoa and viruses in potable water systems. Here we report results obtained from EPLS measurements on two strains of Bacillus spores suspended in water along with comparison with electron microscopy.

Devarakonda, Venkat V.; Manickavasagam, Sivakumar

2009-05-01

37

Culture and characterization of rat hair follicle stem cells.  

PubMed

The purpose of this study was to establish methods for isolation, culture, expansion, and characterization of rat hair follicle stem cells (rHFSCs). Hair follicles were harvested from 1-week-old Sprague-Dawley rats and digested with dispase and collagenase IV. The bulge of the hair follicle was dissected under a microscope and cultured in Dulbecco's modified Eagle's medium/F12 supplemented with KnockOut™ Serum Replacement serum substitute, penicillin-streptomycin, L-glutamine, non-essential amino acids, epidermal growth factor, basic fibroblast growth factor, polyhydric alcohol, and hydrocortisone. The rHFSCs were purified using adhesion to collagen IV. Cells were characterized by detecting marker genes with immunofluorescent staining and real-time polymerase chain reaction (PCR). The proliferation and vitality of rHFSCs at different passages were evaluated. The cultured rHFSCs showed typical cobblestone morphology with good adhesion and colony-forming ability. Expression of keratin 15, integrin ?6, and integrin ?1 were shown by immunocytochemistry staining. On day 1-2, the cells were in the latent phase. On day 5-6, the cells were in the logarithmic phase. Cell vitality gradually decreased from the 7th passage. Real-time PCR showed that the purified rHFSCs had good vitality and proliferative capacity and contained no keratinocytes. Highly purified rHFSCs can be obtained using tissue culture and adhesion to collagen IV. The cultured cells had good proliferative capacity and could therefore be a useful cell source for tissue-engineered hair follicles, vessels, and skin. PMID:25407732

Quan, Renfu; Zheng, Xuan; Ni, Yueming; Xie, Shangju; Li, Changming

2014-11-19

38

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

39

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

40

KIDNEY MORPHOLOGY AND FUNCTION IN THE YOUNG OF RATS MALNOURISHED AND EXPOSED TO NITROFEN DURING PREGNANCY  

EPA Science Inventory

The separate and combined effects of prenatal protein deficiency (65 casein) and prenatal nitrofen exposure (12.5 mg/kg on gestational days 7-21) on renal morphology in the 21-day fetal and postnatal rat were examined. Maternal protein deprivation reduced maternal feed intake, fe...

41

Morphologic Changes in the Pineal Parenchyma Cells of Rats Exposed to Continuous Light or Darkness  

E-print Network

Morphologic Changes in the Pineal Parenchyma Cells of Rats Exposed to Continuous Light or Darkness,Belmont, Massachusetts ONSIDERABLE evidence exists which suggests an antigonadotrophic function for the mammalian pineal, adrenal and pituitary, whereas chronic administration of an aqueous pineal extract counteracts

Wurtman, Richard

42

EFFECTS OF FRUCTOSE-1,6-BISPHOSPHATE ON MORPHOLOGICAL AND FUNCTIONAL NEURONAL INTEGRITY IN RAT HIPPOCAMPAL  

E-print Network

EFFECTS OF FRUCTOSE-1,6-BISPHOSPHATE ON MORPHOLOGICAL AND FUNCTIONAL NEURONAL INTEGRITY IN RAT 63110, USA Abstract--D-Fructose-1,6-bisphosphate, a high energy glyco- lytic intermediate, attenuates ischemic damage in a variety of tissues, including brain. To determine whether D-fructose- 1,6-bisphosphate

Steinbach, Joe Henry

43

[Morphologic changes in the thyroid of rats after a single and fractional gamma-irradiation].  

PubMed

Asynchronous reactions of the thyroid morphological parameters to ionizing radiation were observed in male rats after 24 hours following single and fractional exposure. In delayed periods the thyroid function was suppressed no matter the dose of single and fractional irradiation. PMID:18672514

Shestakova, E N; Vorontsova, Z A; Afanas'ev, R V

2007-01-01

44

Influence of thyroid state on cardiac and renal capillary density and glomerular morphology in rats.  

PubMed

The purpose was to analyse the cardiac and renal capillary density and glomerular morphology resulting from a chronic excess or deficiency of thyroid hormones (THs) in rats. We performed histopathological, morphometrical and immunohistochemical analyses in hypothyroid and hyperthyroid rats to evaluate the density of mesenteric, renal and cardiac vessels at 4 weeks after induction of thyroid disorders. The main angiogenic factors in plasma, heart and kidney were measured as possible mediators of vascular changes. Mesenteric vessel branching was augmented and decreased in hyper- and hypothyroid rats respectively. The numerical density of CD31-positive capillaries was higher in left and right ventricles and in cortical and medullary kidney from both hyper- and hypothyroid rats vs controls. Numbers of podocytes and glomeruli per square millimetre were similar among groups. Glomerular area and percentage mesangium were greater in the hyperthyroid vs control or hypothyroid groups. No morphological renal lesions were observed in any group. Vascularisation of the mesenteric bed is related to TH levels, but an increased capillarity was observed in heart and kidney in both thyroid disorders. This increase may be produced by higher tissue levels of angiogenic factors in hypothyroid rats, whereas haemodynamic factors would predominate in hyperthyroid rats. Our results also indicate that the renal dysfunctions of thyroid disorders are not related to cortical or medullary microvascular rarefaction and that the proteinuria of hyperthyroidism is not secondary to a podocyte deficit. Finally, TH or its analogues may be useful to increase capillarity in renal diseases associated with microvascular rarefaction. PMID:23048210

Rodríguez-Gómez, Isabel; Banegas, Inmaculada; Wangensteen, Rosemary; Quesada, Andrés; Jiménez, Rosario; Gómez-Morales, Mercedes; O'Valle, Francisco; Duarte, Juan; Vargas, Félix

2013-01-01

45

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

46

CHARACTERIZATION OF THE NUDE RAT (rnunz). Functional Characteristics  

Microsoft Academic Search

Gross histopathological and morphological observations in an accompanying paper confirmed the absence of a thymus and thymus-derived lymphocytes in the New Zealand athymic nude mutant (rnunz). In the present studies an analysis of the cell-mediated immune status of the rnunz rat is reported. Lymphocyte transformation studies showed that lymphocytes from the rnunz strain did not respond to mitogenic stimulation with

Elaine Marshall; Thomas Miller

1981-01-01

47

BrainPrint: A discriminative characterization of brain morphology.  

PubMed

We introduce BrainPrint, a compact and discriminative representation of brain morphology. BrainPrint captures shape information of an ensemble of cortical and subcortical structures by solving the eigenvalue problem of the 2D and 3D Laplace-Beltrami operator on triangular (boundary) and tetrahedral (volumetric) meshes. This discriminative characterization enables new ways to study the similarity between brains; the focus can either be on a specific brain structure of interest or on the overall brain similarity. We highlight four applications for BrainPrint in this article: (i) subject identification, (ii) age and sex prediction, (iii) brain asymmetry analysis, and (iv) potential genetic influences on brain morphology. The properties of BrainPrint require the derivation of new algorithms to account for the heterogeneous mix of brain structures with varying discriminative power. We conduct experiments on three datasets, including over 3000 MRI scans from the ADNI database, 436 MRI scans from the OASIS dataset, and 236 MRI scans from the VETSA twin study. All processing steps for obtaining the compact representation are fully automated, making this processing framework particularly attractive for handling large datasets. PMID:25613439

Wachinger, Christian; Golland, Polina; Kremen, William; Fischl, Bruce; Reuter, Martin

2015-04-01

48

Screening, morphological and molecular characterization of fungi producing cystathionine ?-lyase.  

PubMed

The potency for production of cystathionine ?-lyase (CGL) by the fungal isolates was screened. Among the tested twenty-two isolates, Aspergillus carneus was the potent CGL producer (6.29 U/mg), followed by A. ochraceous (6.03 U/mg), A. versicolor (2.51 U/mg), A. candidus (2.12 U/mg), A. niveus and Penicillium notatum (2.0 U/mg). The potent six isolates producing CGL was characterized morphologically, A. carneus KF723837 was further molecularly characterized based on the sequence of 18S-28S rDNA. Upon sulfur starvation, the yield of A. carneus extracellular CGL was increased by about 1.7- and 4.1-fold comparing to non-sulfur starved and L-methionine free medium, respectively. Also, the uptake of L-methionine was duplicated upon sulfur starvation, assuming the activation of specific transporters for L-methionine and efflux of CGL. Also, the intracellular thiols and GDH activity of A. carneus was strongly increased by S starvation, revealing the activation of in vivo metabolic antioxidant systems. Upon irradiation of A. carneus by 2.0 kGy of ?-rays, the activity of CGL was increased by two-fold, regarding to control, with an obvious decreases on its yield upon further doses. Practically, CGL activity from the solid A. carneus cultures, using rice bran as substrate, was increased by 1.2-fold, comparing to submerged cultures, under optimum conditions. PMID:25740443

El-Sayed, Ashraf S; Khalaf, Salwa A; Abdel-Hamid, Gamal; El-Batrik, Mohamed I

2015-03-01

49

Morphological and Molecular Alterations in 1,2 Dimethylhydrazine and Azoxymethane Induced Colon Carcinogenesis in Rats  

PubMed Central

The dimethyhydrazine (DMH) or azoxymethane (AOM) model is a well-established, well-appreciated, and widely used model of experimental colon carcinogenesis. It has many morphological as well as molecular similarities to human sporadic colorectal cancer (CC), which are summarized and discussed in this paper. In addition, the paper combines present knowledge of morphological and molecular features in the multistep development of CC recognized in the DMH/AOM rat model. This understanding is necessary in order to accurately identify and interpret alterations that occur in the colonic mucosa when evaluating natural or pharmacological compounds in DMH/AOM rat colon carcinogenesis. The DMH/AOM model provides a wide range of options for investigating various initiating and environmental factors, the role of specific dietary and genetic factors, and therapeutic options in CC. The limitations of this model and suggested areas in which more research is required are also discussed. PMID:21253581

Perše, Martina; Cerar, Anton

2011-01-01

50

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

51

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...

52

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

53

The effect of probiotics for preventing radiation-induced morphological changes in intestinal mucosa of rats.  

PubMed

Radiation therapy is an important treatment modality for abdominal or pelvic cancer, but there is a common and serious complication such as radiation-induced enteritis. Probiotics is reported to have positive effects against radiation-induced enteropathy. In this study, morphological changes of bowel mucosa were analyzed in rats to presume the effect of probiotics on radiation-induced enteritis and its correlation with radiation dose. A total of 48 adult male Sprague-Dawley rats were randomly assigned to two groups and received a solution containing 1.0×10(8) colony-forming units of Lactiobacillus acidophilus or water once daily for 10 days. Each of two groups was divided into three subgroups and abdomino-pelvic area of each subgroup was irradiated with 10, 15, and 20 Gy, respectively on the seventh day of feeding the solutions. All rats were sacrificed 3 days after irradiation and the mucosal thickness and villus height of jejunum, ileum and colon were measured. The morphological parameters of the small intestine represented significant differences between two solution groups irradiated 10 or 15 Gy, except for villus height of jejunum in 15 Gy-subgroup (P=0.065). There was no significant morphometric difference between two groups irradiated with 20 Gy of radiation. Probiotics appear to be effective for the morphological shortening of small intestinal mucosa damaged by radiation less than or equal to 15 Gy. PMID:25368490

Ki, Yongkan; Kim, Wontaek; Cho, Heunglae; Ahn, Kijung; Choi, Youngmin; Kim, Dongwon

2014-10-01

54

Crimp morphology in relaxed and stretched rat Achilles tendon.  

PubMed

Fibrous extracellular matrix of tendon is considered to be an inextensible anatomical structure consisting of type I collagen fibrils arranged in parallel bundles. Under polarized light microscopy the collagen fibre bundles appear crimped with alternating dark and light transverse bands. This study describes the ultrastructure of the collagen fibrils in crimps of both relaxed and in vivo stretched rat Achilles tendon. Under polarized light microscopy crimps of relaxed Achilles tendons appear as isosceles or scalene triangles of different size. Tendon crimps observed via SEM and TEM show the single collagen fibrils that suddenly change their direction containing knots. The fibrils appear partially squeezed in the knots, bent on the same plane like bayonets, or twisted and bent. Moreover some of them lose their D-period, revealing their microfibrillar component. These particular aspects of collagen fibrils inside each tendon crimp have been termed 'fibrillar crimps' and may fulfil the same functional role. When tendon is physiologically stretched in vivo the tendon crimps decrease in number (46.7%) (P<0.01) and appear more flattened with an increase in the crimp top angle (165 degrees in stretched tendons vs. 148 degrees in relaxed tendons, P<0.005). Under SEM and TEM, the 'fibrillar crimps' are still present, never losing their structural identity in straightened collagen fibril bundles of stretched tendons even where tendon crimps are not detectable. These data suggest that the 'fibrillar crimp' may be the true structural component of the tendon crimp acting as a shock absorber during physiological stretching of Achilles tendon. PMID:17229278

Franchi, Marco; Fini, Milena; Quaranta, Marilisa; De Pasquale, Viviana; Raspanti, Mario; Giavaresi, Gianluca; Ottani, Vittoria; Ruggeri, Alessandro

2007-01-01

55

Morphological divergence of breeders and helpers in wild Damaraland mole-rat societies.  

PubMed

The specialization of body shape to an individual's role within society represents a pinnacle of social evolution. Although commonplace among social insects, divergence in the body shapes of breeders and helpers has to date been documented in just one social vertebrate, the naked mole-rat, Heterocephalus glaber; an extraordinary species in which large colony size and frequent inbreeding may have favored the evolution of such specialization. Here, we present new evidence of morphological divergence between breeders and helpers in the Damaraland mole-rat, Fukomys damarensis; a much less socially extreme species that reflects an independent evolutionary origin of sociality. Using longitudinal data from wild populations, we show that dominant female Damaraland mole-rats, like many social insect queens, have a significantly more elongate body shape than subordinates. This difference arises not from a pre-existing difference in the body shapes of subordinates that do, and those that do not, become dominant, but from a modification to the growth trajectory of subordinates on dominance acquisition. Our findings reveal a wider role for morphological divergence within vertebrate societies and, as Damaraland mole-rats neither live in unusually large groups nor inbreed, suggest that circumstances favoring the evolution of such specializations may be more widespread among vertebrates than previously supposed. PMID:20561049

Young, Andrew J; Bennett, Nigel C

2010-11-01

56

Dietary high-fat lard intake induces thyroid dysfunction and abnormal morphology in rats  

PubMed Central

Aim: Excess dietary fat intake can induce lipotoxicity in non-adipose tissues. The aim of this study was to observe the effects of dietary high-fat lard intake on thyroid in rats. Methods: Male Sprague-Dawley rats were fed a high-fat lard diet for 24 weeks, and then the rats were fed a normal control diet (acute dietary modification) or the high-fat lard diet for another 6 weeks. The serum lipid profile, total thyroxine (TT4), free thyroxine (FT4) and thyrotropin (TSH) levels were determined at the 12, 18, 24 and 30 weeks. High-frequency ultrasound scanning of the thyroid glands was performed at the 24 or 30 weeks. After the rats were sacrificed, the thyroid glands were collected for histological and immunohistochemical analyses. Results: The high-fat lard diet significantly increased triglyceride levels in both the serum and thyroid, and decreased serum TT4 and FT4 levels in parallel with elevated serum TSH levels. Ultrasonic imaging revealed enlarged thyroid glands with lowered echotexture and relatively heterogeneous features in the high-fat lard fed rats. The thyroid glands from the high-fat lard fed rats exhibited enlarged follicle cavities and flattened follicular epithelial cells under light microscopy, and dilated endoplasmic reticulum cisternae, twisted nuclei, fewer microvilli and secretory vesicles under transmission electron microscopy. Furthermore, the thyroid glands from the high-fat lard fed rats showed markedly low levels of thyroid hormone synthesis-related proteins TTF-1 and NIS. Acute dietary modification by withdrawal of the high-fat lard diet for 6 weeks failed to ameliorate the high-fat lard diet-induced thyroid changes. Conclusion: Dietary high-fat lard intake induces significant thyroid dysfunction and abnormal morphology in rats, which can not be corrected by short-term dietary modification. PMID:25263336

Shao, Shan-shan; Zhao, Yuan-fei; Song, Yong-feng; Xu, Chao; Yang, Jian-mei; Xuan, Shi-meng; Yan, Hui-li; Yu, Chun-xiao; Zhao, Meng; Xu, Jin; Zhao, Jia-jun

2014-01-01

57

Derivation and Characterization of Embryonic Stem Cells Lines Derived from Transgenic Fischer 344 and Dark Agouti Rats  

PubMed Central

Rat embryonic stem cell (ESC) lines are not widely available, and there are only 2 lines available for distribution. Here, ESC lines were derived and characterized from Fischer 344 (F344) rats that express marker transgenes either ?-galactosidase or human placental alkaline phosphatase (AP), nontransgenic F344 rats, and from Dark Agouti (DA) rats. The ESC lines were maintained in an undifferentiated state as characterized by colony morphology, expression of Oct4, Nanog, Sox-2, Cdx2, and Stella, staining for AP, and stage-specific embryonic antigen-1. Pluripotency was demonstrated in vitro by differentiation to embryoid bodies, followed by embryonic monsters. The Cdx2 expression by ESCs was unexpected and was confirmed via reverse transcriptase-polymerase chain reaction, immunocytochemistry. Pluripotency of ESCs was demonstrated in vivo by production of teratoma after an injection into F344 nontransgenic rats, and by an injection of male DA ESCs into F344 or Sprague-Dawley rat blastocysts and the generation of chimeric rats and germline contribution. ESCs from both F344 and DA contributed to chimeric rats, and one DA ESC line was proved to be germline competent. ESC sublines were created by transfection with a plasmid expressing enhanced green fluorescent protein (eGFP) under the control of a beta actin promoter and cytomegalovirus enhancer (pCX-eGFP) or by transfection with a plasmid expressing GFP under the control of a 3.1?kb portion of the rat Oct4 promoter (pN1-Oct4-GFP). In pN1-Oct4-GFP sublines, GFP gene expression and fluorescence were shown to be correlated with endogenous Oct4 gene expression. Therefore, these new ESC lines may be useful for tissue engineering and transplantation studies or for optimizing culture conditions required for self-renewal and differentiation of rat ESCs. While they made chimeric rats, further work is needed to confirm whether the transgenic F344 rat ESCs described here are germline-competent ESCs. PMID:21995453

Hong, James; He, Hong

2012-01-01

58

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

59

Quantitative methods to characterize morphological properties of cell lines.  

PubMed

Descriptive terms are often used to characterize cells in culture, but the use of nonquantitative and poorly defined terms can lead to ambiguities when comparing data from different laboratories. Although recently there has been a good deal of interest in unambiguous identification of cell lines via their genetic markers, it is also critical to have definitive, quantitative metrics to describe cell phenotypic characteristics. Quantitative metrics of cell phenotype will aid the comparison of data from experiments performed at different times and in different laboratories where influences such as the age of the population and differences in culture conditions or protocols can potentially affect cellular metabolic state and gene expression in the absence of changes in the genetic profile. Here, we present examples of robust methodologies for quantitatively assessing characteristics of cell morphology and cell-cell interactions, and of growth rates of cells within the population. We performed these analyses with endothelial cell lines derived from dolphin, bovine and human, and with a mouse fibroblast cell line. These metrics quantify some characteristics of these cells lines that clearly distinguish them from one another, and provide quantitative information on phenotypic changes in one of the cell lines over large number of passages. PMID:22619183

Mancia, Annalaura; Elliott, John T; Halter, Michael; Bhadriraju, Kiran; Tona, Alessandro; Spurlin, Tighe A; Middlebrooks, Bobby L; Baatz, John E; Warr, Gregory W; Plant, Anne L

2012-07-01

60

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

61

Rapid morphological change in black rats (Rattus rattus) after an island introduction  

PubMed Central

Rapid morphological change has been shown in rodent populations on islands, including endemic deer mice (Peromyscus maniculatus subspp.) on the California Channel Islands. Surprisingly, most of these changes were towards a smaller size. Black rats were introduced to Anacapa Island in the mid-1800s (probably in 1853) and eradicated in 2001–2002. To assess possible changes in these rats since their introduction, eleven cranial and four standard external measurements were taken from 59 Rattus rattus specimens collected from 1940–2000. All rat cranial traits changed 3.06–10.43% (724–2567 d, 0.06–0.42 h), and all became larger. When considered in haldanes, these changes are among the fastest on record in any organism, and far exceed changes found in other island rodents. These changes were confirmed by MANOVA (Wilk’s ? < 0.0005, Fd.f.15 = 2974.386, P < 0.0005), and all 11 cranial traits significantly fit linear regressions. We speculate that concurrent changes in mice may have been due in part to competition with and/or predation by rats. Future research might evaluate whether the vector of mouse evolution on Anacapa is again changing after rat eradication. PMID:25780765

Byrn, David; Lee, Kashawneda L.Y.; Jackson, Racheal

2015-01-01

62

Effect of single-dose amoxicillin on rat incisor odontogenesis: a morphological study.  

PubMed

The effect of exposure to amoxicillin on tooth development remains to be elucidated. The purpose of this study was to investigate the effect of amoxicillin on rat incisor odontogenesis. Male Wistar rats weighing approximately 100 g were given a single intraperitoneal injection of 3.0 g/kg body weight amoxicillin. One week after injection, the rats were fixed, and the lower incisors were demineralized and prepared into paraffin sections for light microscopy (LM) and immunohistochemistry. Undemineralized samples were embedded in resin and ground for processing for contact microradiography (CMR) and scanning electron microscopy (SEM). Serum calcium, phosphate, and magnesium concentrations were measured. At 1 week after amoxicillin administration, LM, CMR, and SEM revealed a clear increase in the area of interglobular dentin, representing disruption of mineralization by odontoblasts. Immunohistochemistry demonstrated moderate levels of the small integrin-binding ligand N-linked glycoprotein family dentin matrix protein 1 in large areas of interglobular dentin. On the other hand, no morphological alteration or hypomineralization was observed in the enamel. Serum calcium values showed no significant differences between the control and experimental rats during the experimental period although both serum phosphate and magnesium levels increased at day 1 after amoxicillin injection. The results suggest that a single dose of amoxicillin specifically affects normal tooth dentin mineralization, but not enamel mineralization in rat incisor odontogenesis. The present results further our understanding of the clinical association between dentin abnormality and amoxicillin exposure during tooth development. PMID:21717095

Kumazawa, Kaido; Sawada, Takashi; Yanagisawa, Takaaki; Shintani, Seikou

2012-06-01

63

Morphological and functional changes in the rat heart after X irradiation: Strain differences  

SciTech Connect

The hearts of mature male rats of the Wistar and Sprague-Dawley strains were locally irradiated with single doses of 17.5 and 20.0 Gy of X rays, respectively. These two dose levels had previously been shown to result in a comparable latent period between irradiation and the death of rats of these two strains from cardiac failure. Morphological changes in the myocardium and modifications in cardiac function were assessed in the animals at 28, 70, and 100 days after irradiation. The first radiation-induced change which was observed in the myocardium was a rapid decline in capillary density and a loss of alkaline phosphatase activity by the capillary endothelial cells. The capillary density was reduced to approximately 50% of that of unirradiated control values at 28 days and to approximately 40% of the control values between 70 and 100 days after irradiation. The loss of enzyme activity was also detected at 28 days. Examination of histological sections showed an increase by 70 days in the areas with negative enzyme activity up to approximately 70% of the myocardium. The reduction in capillary density and the loss of enzyme activity occurred before any marked pathological changes were seen in the myocardium. The pathological lesions seen in the myocardium at 100 days after irradiation were qualitatively and quantitatively the same in the two strains of rat. Measurements of cardiac output in Sprague-Dawley rats showed a gradual decline in output after irradiation; however, measurements in Wistar rats showed a progressive increase in cardiac output over the same period of time. It was shown by rubidium extraction that there was an increase in the percentage of the total cardiac output distributed to the ventricular muscle of Sprague-Dawley rats, while similar measurements in Wistar rats showed no significant change.

Yeung, T.K.; Lauk, S.; Simmonds, R.H.; Hopewell, J.W.; Trott, K.R. (Univ. of Oxford (England))

1989-09-01

64

Prevalence of activating ras mutations in morphologically characterized thyroid nodules.  

PubMed

Ras proteins are signal-transducing proteins that share common properties with membrane-anchored G proteins. Mutations at codon 12/13 or codon 61 alter GTP-binding or GTPase activity, respectively. Such activating mutations are present in nearly 30-50% of various malignancies including colon, breast, and lung carcinomas. There are conflicting data regarding the prevalence of ras mutations in the thyroid and their possible pathogenetic role in the different tumor types. To address this question, we examined 45 morphologically characterized thyroid carcinomas, adenomas, and hyperplastic nodules using a highly sensitive single-stranded conformation polymorphism (SSCP) approach combined with DNA-sequencing. DNA from cell lines with known mutations served as controls. A G to A H13 codon substitution replacing an Asp for a Gly residue was detected in 1 papillary carcinoma. Although no H12 or H61 codon substitutions were identified, 2 discrete alterations were identified in codons H17 and 22. No N12/13 codon substitutions were identified. N61 codon substitutions of A to G resulting in a Gly to Arg substitution were detected in 2 papillary carcinomas; the same mutation was also found in one follicular adenoma. Interestingly, K12/13 and K61 ras mutations were not present in any of the tumors examined. These data establish a low prevalence of mutations in all ras gene family members in human thyroid neoplasms. This difference from neoplasms of other organs may explain the relatively indolent biologic behavior of many thyroid tumors and supports an alternate early genetic mutation that is more characteristic of these neoplasms. PMID:8936664

Ezzat, S; Zheng, L; Kolenda, J; Safarian, A; Freeman, J L; Asa, S L

1996-10-01

65

Testis morphology in rats chronically treated with letrozole, an aromatase inhibitor.  

PubMed

The aim of this study was to investigate the influence of the long-term treatment of rats with letrozole on the testis morphology. The pharmacologically induced estrogen deficiency caused statistically significant decreases of both intratesticular and serum levels of estradiol, and morphological changes in the seminiferous epithelium and in the interstitial tissue of the testes. Six months of treatment resulted in the sloughing of premature germ cells of the seminiferous epithelium into the tubular lumen and in intraepithelial vacuolization. Multinucleated giant cells composed of premature germ cells, conglomerates of various cell nuclei and cell debris as well as irregularities and infoldings of the tubular basement membrane were also seen. Moreover, deep invaginations of the lamina propria with myoid cells were observed. Cells in the interstitial tissue showed changes similar to that observed in aging processes. The cytoplasm of LH-R-positive Leydig cells was loaded with lipofuscin granules. The number of lipofuscin-loaded cells was significantly increased in the interstitial tissue of testis in letrozole-treated rats. The results indicate the direct influence of estrogens on seminiferous tubules and the interstitial tissue morphology. PMID:22252764

Kondarewicz, Anna; Kolasa, Agnieszka; Zawi?lak, Bartosz; Baranowska-Bosiacka, Irena; Marchlewicz, Mariola; Wenda-Ró?ewicka, Lidia; Wiszniewska, Barbara

2011-01-01

66

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

67

Baicalin influences the dendritic morphology of newborn neurons in the hippocampus of chronically stressed rats?  

PubMed Central

Chronic stress models, established in adult Sprague-Dawley rats through a 14-day subcutaneous injection of 40 mg/kg corticosterone, once per day, were given a daily oral feeding of 50 mg/kg baicalin. The study was an attempt to observe the effect of baicalin on neurogenesis in chronically stressed rats. Results showed that subcutaneous injection of corticosterone significantly decreased the total number of doublecortin-positive neurons in the hippocampus. The reduced cell number caused by corticosterone was mainly due to the decrease of class II doublecortin-positive neurons, but the class I doublecortin-positive neurons were unaffected. Baicalin treatment increased the number of both class I and class II doublecortin-positive neurons. In addition, doublecortin-positive neurons showed less complexity in dendritic morphology after corticosterone injection, and this change was totally reversed by baicalin treatment. These findings suggest that baicalin exhibits a beneficial effect on adult neurogenesis. PMID:25206692

Jiang, Xinghua; Xu, Junmei; Zou, Dingquan; Yang, Lin; Wang, Yaping

2013-01-01

68

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

69

Effect of the duration of bladder overdistention on renal function and morphology in rats  

PubMed Central

The aim of this study was to investigate the influence of the duration of bladder overdistention (DOBO) on kidney structure and function in rats. Bladder overdistention was induced in male Sprague-Dawley rats by an infusion of saline. Forty rats were divided into five groups: DOBO 1, 2, 4 or 8 h groups and the control. Renal function was evaluated using serum creatinine (SCr) and blood urea nitrogen (BUN). Apoptotic indices and morphologic changes of the kidney were detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) staining and transmission electron microscopy (TEM). Compared with the control, rats undergoing 2, 4 or 8 h of overdistention showed significant, time-dependent increases in SCr (12.375 vs. 23.125, 34.375 and 51.500 ?mol/l, respectively), BUN (6.980 vs. 18.689, 25.184 and 32.079 mmol/l, respectively), renal size (1.041 vs. 1.472, 1.484 and 1.634 cm3, respectively) and renal pelvis separation (0.000 vs. 0.223, 0.320, 0.308 and 0.277 cm, respectively; P<0.01). In the rats, 2, 4 and 8 h of overdistention elicited time-dependent increases in the blood flow rate in the main renal artery (MRA; 44.827 vs. 49.082, 59.688 and 67.123 cm3/sec, control vs. DOBO 2, 4 and 8 h), the interlobar renal artery (IRA; 32.095 vs. 39.16 and 51.745 cm3/sec, control vs. DOBO 4 and 8 h) and the segmental renal artery (SRA; 21.171 vs. 24.355 and 25.358 cm3/sec, control vs. DOBO 4 and 8 h; P<0.01). TUNEL results showed that prolonged overdistention increased the apoptotic index of renal cells significantly (1.15, 1.77, 3.40, 5.34 and 13.91% for control and DOBO 1, 2, 4 and 8 h, respectively; P<0.01) and TEM indicated that prolonged overdistention resulted in ultrastructural injuries of increased severity. DOBO plays a significant role in the functional and structural impairment of the rat kidney. With increasing duration, the hemodynamic changes, cell apoptosis and ultrastructural injuries of the kidney are more evident, all of which may contribute to the increasingly serious impairment of renal function and morphology. PMID:23837061

MENG, HONG-ZHOU; CAO, MIN; XIANG, JIAN-JIAN; ZHOU, XIE-LAI; YIN, HONG-PING; JIN, BAI-YE; CHEN, ZHAO-DIAN; JIN, XIAO-DONG

2013-01-01

70

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

71

Morphological studies of metastatic mammary rat tumors after laser immunotherapy treatment  

NASA Astrophysics Data System (ADS)

Laser immunotherapy, using a combination of 805 nm diode laser, photosensitizer indocyanine green and immunoadjuvant glycated chitosan, has shown an induced anti-tumor immune response in treatment of metastatic rat tumors. In additional to an apparent systemic, long-term humoral immunological reaction, there could also be laser induced local cellular immune responses. A morphological study was performed to study the immune cells and their infiltration to tumor tissue after this laser immunotherapy treatment. Tumor-bearing rats were terminated at designated times after the treatment; both the tumor and the surrounding normal tissue were collected. The tissue samples were observed under electron microscope. The number and types of infiltrating cells at the tumor site were studied after treatment to determine the contribution of these cells in the elimination of tumors. The tumor cell structural changes resulted from laser-tissue photothermal interaction was investigated. The morphology of tumor development and activities of immune cells including both lymphocytes and plasma cells could shed light on the mode of action of laser treatment of tumors.

Nordquist, Robert E.; Nordquist, John A.; Agee, James C.; Blomquist, Chad M.; Chen, Wei R.

1998-05-01

72

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

73

Morphological development and maturation of granule neuron dendrites in the rat dentate gyrus.  

PubMed

The first granule neurons in the dentate gyrus are born during late embryogenesis in the rodent, and the primary period of granule cell neurogenesis continues into the second postnatal week. On the day of birth in the rat, the oldest granule neurons are visible in the suprapyramidal blade and exhibit rudimentary dendrites extending into the molecular layer. Here we describe the morphological development of the dendritic trees between birth and day 14, and we then review the process of dendritic remodeling that occurs after the end of the second week. Data indicate that the first adult-like granule neurons are present on day 7, and, furthermore, physiological recordings demonstrate that some granule neurons are functional at this time. Taken together, these results suggest that the dentate gyrus may be incorporated into the hippocampal circuit as early as the end of the first week. The dendritic trees of the granule neurons, however, continue to increase in size until day 14. After that time, the dendritic trees of the oldest granule neurons are sculpted and refined. Some dendrites elongate while others are lost, resulting in a conservation of total dendritic length. We end this chapter with a review of the quantitative aspects of granule cell dendrites in the adult rat and a discussion of the relationship between the morphology of a granule neuron and the location of its cell body within stratum granulosum and along the transverse axis of the dentate gyrus. PMID:17765718

Rahimi, Omid; Claiborne, Brenda J

2007-01-01

74

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; Leão, Jair Carneiro; Evêncio, Liriane Baratella; Porter, Stephen Ross; de Castro, Raul Manhães

2010-01-01

75

Expression of developmental myosin and morphological characteristics in adult rat skeletal muscle following exercise-induced injury  

Microsoft Academic Search

The extent and stability of the expression of developmental isoforms of myosin heavy chain (MHCd), and their association\\u000a with cellular morphology, were determined in adult rat skeletal muscle fibres following injury induced by eccentrically-biased\\u000a exercise. Adult female Wistar rats [274 (10)?g] were either assigned as non-exercised controls or subjected to 30?min of treadmill\\u000a exercise (grade, ?16°; speed, 15?m?·?min?1), and then

H. K. Smith; M. J. Plyley; C. D. Rodgers; N. H. McKee

1999-01-01

76

Rapid morphological brain abnormalities during acute methamphetamine intoxication in the rat: An experimental study using light and electron microscopy  

Microsoft Academic Search

This study describes morphological abnormalities of brain cells during acute methamphetamine (METH) intoxication in the rat and demonstrates the role of hyperthermia, disruption of the blood–brain barrier (BBB) and edema in their development. Rats with chronically implanted brain, muscle and skin temperature probes and an intravenous (i.v.) catheter were exposed to METH (9mg\\/kg) at standard (23°C) and warm (29°C) ambient

Hari S. Sharma; Eugene A. Kiyatkin

2009-01-01

77

Specific Reactions of Different Striatal Neuron Types in Morphology Induced by Quinolinic Acid in Rats  

PubMed Central

Huntington's disease (HD) is a neurological degenerative disease and quinolinic acid (QA) has been used to establish HD model in animals through the mechanism of excitotoxicity. Yet the specific pathological changes and the underlying mechanisms are not fully elucidated. We aimed to reveal the specific morphological changes of different striatal neurons in the HD model. Sprague-Dawley (SD) rats were subjected to unilaterally intrastriatal injections of QA to mimic the HD model. Behavioral tests, histochemical and immunhistochemical stainings as well as Western blots were applied in the present study. The results showed that QA-treated rats had obvious motor and cognitive impairments when compared with the control group. Immunohistochemical detection showed a great loss of NeuN+ neurons and Darpp32+ projection neurons in the transition zone in the QA group when compared with the control group. The numbers of parvalbumin (Parv)+ and neuropeptide Y (NPY)+ interneurons were both significantly reduced while those of calretinin (Cr)+ and choline acetyltransferase (ChAT)+ were not changed notably in the transition zone in the QA group when compared to the controls. Parv+, NPY+ and ChAT+ interneurons were not significantly increased in fiber density while Cr+ neurons displayed an obvious increase in fiber density in the transition zone in QA-treated rats. The varicosity densities of Parv+, Cr+ and NPY+ interneurons were all raised in the transition zone after QA treatment. In conclusion, the present study revealed that QA induced obvious behavioral changes as well as a general loss of striatal projection neurons and specific morphological changes in different striatal interneurons, which may help further explain the underlying mechanisms and the specific functions of various striatal neurons in the pathological process of HD. PMID:24632560

Mu, Shuhua; Wu, Jiajia; Chen, Si; OuYang, Lisi; Lei, Wanlong

2014-01-01

78

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. PMID:25540743

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

2014-01-01

79

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

80

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...

81

Characterization of the vasculature supplying the genital tissues in female rats  

PubMed Central

Introduction The internal pudendal arteries are the key resistance vessels controlling the peripheral circulatory component of sexual responses in both male and females. Previous studies in the male rat demonstrated that this vessel has markedly heightened susceptibility to vascular damage compared to other vessels in the body. Evidence suggests that the female may also be susceptible to vascular pathologies contributing to sexual dysfunction. Aim To characterize the anatomical, morphological and functional properties of the pudendal artery in female rats. Methods The pelvic arteries in young Sprague-Dawley female rats were dissected to generate a composite representation of the vascular gross anatomy. Morphometry was performed on perfusion-fixed pudendal arteries whereas others were mounted in a wire myograph to assess responses to vasoactive drugs. These measures were contrasted with a previous study examining male rats. Main Outcomes Measured Gross anatomy, lumen diameter, wall thickness, cross sectional area and contractile responses in the internal pudendal artery. Results The gross anatomy of the pudendal artery in female rats appears to parallel that found in male rats; acting as the primary feeder vessel of the clitoral, labial and vaginal tissue. Compared to the male rat, the female pudendal artery has a smaller lumen diameter (169±5.7 vs 303±13.8um), wall thickness (14±0.7 vs 47±2.2um) and cross-sectional area (8±0.4 vs 52±3.4×103 ?m2). These structural differences also translate into a decreased contractile capacity of the pudendal arteries from female rats vs. males (8.1±2.7 vs 20±1.4mN). Conclusions Although the gross anatomical features of the vasculature tree supplying the genital tissue in male and female rats appears to have similarities, the tissue specific properties of the vessel itself has a very different structure-function balance. We hypothesize this discordance likely reflects the very different sex-specific roles of this vessel in regulating blood flow during arousal. PMID:22023507

Hannan, Johanna L.; Cheung, Geoffrey L.; Blaser, Mark C.; Pang, Judith J.; Pang, Stephen C.; Webb, R. Clinton; Adams, Michael A.

2011-01-01

82

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

83

Isoflavone Genistein Induces Fluid Secretion and Morphological Changes in the Uteri of Post-Pubertal Rats  

PubMed Central

A reported increase in the incidence of infertility following high genistein intake could be related to alteration in the normal fluid volume and morphology of the uterus in adult female. In view of this, we investigated the effect of this compound on fluid secretion, fluid volume and morphology of the uterus in post-pubertal rats. Methods: Ovariectomised SD rats were treated with 17-? oestradiol (E) (0.8 X 10-4 mg/kg/day) and genistein (0.5, 5, 10, 25, 50 and 100 mg/kg/day) for three days. Following drug treatment, in-vivo uterine perfusion was performed and the rate of fluid secretion and the volume of fluid in the uterus were determined via changes in weight (?l/min) and F-dextran concentration of the perfusate respectively. The animals were then sacrificed and the uteri were removed for weight determination, morphological analyses and proliferative cell nuclear antigen (PCNA) expression analyses by Western blotting. Results: Subcutaneous genistein treatment resulted in a dose-dependent increase in fluid secretion rate, fluid volume and uterine wet weight. Treatment with 100 mg/kg/day genistein resulted in a remarkable increase in the rate of uterine fluid secretion, the volume of the uterine luminal fluid as well as the circumference of the uterine and uterine glandular lumen suggesting an excessive fluid accumulation. Meanwhile, there were evidence of glandular hyperplasia and an increase in the expression of PCNA following treatment with 50 and 100 mg/kg/day genistein. Conclusion: High genistein intake could potentially cause adverse effects on the uterus by inducing excessive fluid secretion and accumulation as well as hyperplasia. PMID:23569430

Salleh, Naguib; Helmy, Mohd Mokhtar; Fadila, Kasim Nor; Yeong, Soh Onn

2013-01-01

84

The effects of chronic restraint on the morphology of ventral CA1 neurons in female Long Evans rats.  

PubMed

Abstract Women are more likely than men to develop psychopathology as a result of stress, but there is little research regarding the effects of a stressful condition and its treatment in female non-human animals, perhaps because of inherent hormonal activity. Recent studies have demonstrated that there are structural and functional differences between the dorsal and ventral hippocampus, but the effects of stress on the morphology of CA1 and CA3 neurons have been studied primarily in the dorsal hippocampus. This study assessed the effects of stress induced by restricted movement on the morphology of ventral hippocampal CA1 neurons in male and female rats. Male and female Long Evans (LE) rats were subjected to restraint stress for 6?h every day for 25 days. One group of rats was used to study the dendritic morphology of CA1 ventral hippocampal neurons using the Golgi-Cox stain. A second group of rats was used to analyze learning and memory using the Morris water maze. Stressed female rats exhibited a decrease in the density of basilar dendritic spines, an increase in the number of apical dendritic intersections and deficits in spatial memory. There were no apparent effects of stress on male rats. Our data support previous findings of a dimorphic response to chronic stress and indicate that the ventral hippocampus is not particularly susceptible to the effects of stress. PMID:25287136

Morales Rico, Alexander; López Mendoza, Anayeli; Bravo Durán, Dolores Adriana; de la Luz Torres, Héctor; Arias Mendoza, Guadalupe; Silva Gómez, Adriana Berenice

2015-01-01

85

Alteration in axial motoneuronal morphology in the spinal cord injured spastic rat.  

PubMed

Following spinal cord injury (SCI), exaggerated reflexes and muscle tone emerge that contribute to a general spastic syndrome in humans. At present, the underlying mechanisms involved with the development of spasticity following traumatic spinal cord injury, especially with regard to axial musculature, remains unclear. The purpose of the present study was to examine the temporal changes in sacrocaudal motoneuronal morphology following complete transection of the sacral spinal cord and to correlate these changes with the onset and progression of spasticity within the tail musculature. The spinal cords of rats were transected at the upper sacral (S(2)) level. Animals were behaviorally tested for the onset and progression of spasticity in the tail and at 1, 2, 4, or 12 weeks postinjury were sacrificed. At these time points, the animals demonstrated stage 1, 2, 3, or 4 spastic behavior, respectively. Sacrocaudal motoneurons innervating selected flexor muscles within the tail were retrogradely labeled with cholera toxin beta-subunit and neuronal morphology was analyzed using a combination of immunocytochemistry and standard microscopy. Initially over the first 2 weeks postinjury, a transient increase in the lengths of primary and secondary dendrites occurred. However, a progressive decrease in the overall number of dendritic branches was observed between 2 and 12 weeks postinjury, which parallels the time frame for the progressive increase in spastic behavior in the tail musculature. Following spinal cord injury, there is an alteration in the morphology of tail flexor motoneurons, which may be relevant to the development of spasticity within the tail. PMID:15698623

Kitzman, Patrick

2005-03-01

86

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

87

Morphological and functional features of the sex steroid-responsive posterodorsal medial amygdala of adult rats.  

PubMed

The rat posterodorsal medial amygdala (MePD) expresses receptors for gonadal hormones and integrates sex steroid-sensitive subcortical networks. Male-female differences are found in the morphology, connectivity, and local neuropil structure of MePD. For example, dendritic spine density is sexually-dimorphic and changes with the estrous cycle and following gonadal hormones manipulations. Due to its connectivity, the MePD may affect emotionally-loaded social behaviors, according to a former Newman's seminal proposition. Unilateral fiber-sparing ibotenic acid damage of the MePD does not impair male sexual behavior. However, microinjecting glutamate and histamine into the right MePD facilitates ejaculation. Further, MePD-lesioned rats are not different from normal rats in anxiety-like behavior as evaluated by the elevated plus maze test or innate fear test induced by a live cat. In another study, an adapted model for inducing aggressive behavior in rats by a brief period of restraint prior to the resident-intruder paradigm was used to study Fos-immunoreactivity in the MePD. Following stressful stimulation (restraint) or the restraint and fight condition, but not after aggression alone, Fos-immunoreactivity was detected in the MePD. Microinjecting the inhibitory neuropeptide somatostatin into the right MePD notably reduces fighting behavior without affecting locomotion. Overall, these data indicate that sex steroids and local neurochemical stimulatory/inhibitory transmitters modulate the MePD and reinforce the idea that this area is a node for modulating social behavior neural networks. PMID:22827219

Rasia-Filho, A A; Haas, D; de Oliveira, A P; de Castilhos, J; Frey, R; Stein, D; Lazzari, V M; Back, F; Pires, G N; Pavesi, E; Winkelmann-Duarte, E C; Giovenardi, M

2012-10-01

88

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

89

Morphological characterization of a polymeric microfiltration membrane by synchrotron radiation computed microtomography  

E-print Network

to characterize the 3D structure of a PvDF hollow fibre microfiltration membrane prepared by phase inversion. 3D1 Morphological characterization of a polymeric microfiltration membrane by synchrotron radiation membranes are prepared by phase inversion. The performance of the membranes depends greatly

Paris-Sud XI, Université de

90

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

91

Characterization and subcellular distribution of somatogenic receptor in rat liver  

SciTech Connect

Binding of (/sup 125/I)iodobovine GH ((/sup 125/I)iodo-bGH) to rat liver microsomes and Golgi/endosomal fractions isolated from male and female rats has been characterized. Binding of bGH to a pure somatogenic site was suggested by the finding that 50% inhibition of (/sup 125/I)iodo-bGH binding required 5-130 ng bGH, rGH, or hGH/incubation, while around 500 ng rat PRL/incubation were needed to obtain the same effect. Binding of (/sup 125/I)iodo-bGH to microsomes and Golgi/endosomes was time, temperature, and protein dependent. Maximal specific binding occurred at 15-16 and 15-20 h at 22 C in Golgi and microsomal membranes, respectively. Subcellular distribution studies demonstrated in the Golgi/endosomal fractions compared to the total particulate fraction, while residual microsomes devoid of Golgi/endosomal-derived components were approximately 2-fold enriched. Low levels of somatogenic receptors were detected in lysosome-enriched fractions. Removal of endogenous ligand by treating Golgi/endosomal membranes with 3M MgCl/sub 2/ increased specific binding of bGH about 2- to 3-fold. These results indicate that approximately 50% of specific somatogenic binding sites in the low density fractions represent internalized ligand-receptor complexes. The level of rat liver somatogenic receptors did not show a pronounced sex differentiation; however, an endocrine dependence of somatogenic receptor levels is suggested by the finding that livers from rats in the late stages of pregnancy had a level of somatogenic receptors exceeding that of nonpregnant rats.

Husman, B.; Andersson, G.; Norstedt, G.; Gustafsson, J.A.

1985-06-01

92

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

93

Functional and morphological effects of grape seed proanthocyanidins on peripheral neuropathy in rats with type 2 diabetes mellitus.  

PubMed

Grape seed proanthocyanidins (GSPs) possess a broad spectrum of pharmacological and therapeutic properties. The aim of this study was to examine the effect of GSPs on functional and morphological abnormalities in the peripheral nerves of rats with type 2 diabetes mellitus. Diabetic rats were induced by two injections of 25?mg streptozotocin/kg body weight and 8?weeks of a high-carbohydrate/high-fat diet. GSPs were then administrated to the rats for 16?weeks. Thermal and mechanical sensitivity thresholds and nerve conductive velocity were measured to evaluate peripheral nerve function. Light microscopy was used with special stains to observe the morphological changes in the central and peripheral nervous systems. Calcium (Ca(2+)) homeostasis and ATPase activities in the sciatic nerves were also determined. In diabetic rats receiving GSP treatment (especially at the 500?mg/kg dose), the abnormal peripheral nerve function and impaired nervous tissues (L4 to L5 spinal cord segments, L5 dorsal root ganglion, and sciatic nerves) were improved to a significant extent. Moreover, 500?mg/kg GSP treatment significantly reduced the concentration of free Ca(2+) and elevated Ca(2+)-ATPase activity in sciatic nerves. These results suggest that GSPs may prevent early functional and morphological abnormalities in the peripheral nerves of rats with type 2 diabetes mellitus. PMID:24343984

Ding, Ye; Dai, Xiaoqian; Jiang, Yanfei; Zhang, Zhaofeng; Li, Yong

2014-07-01

94

Synthesis and Morphological Characterization of Block Copolymers for Improved Biomaterials  

PubMed Central

Biocompatible polymers are known to act as scaffolds for the regeneration and growth of bone. Block copolymers are of interest as scaffold materials because a number of the blocks are biocompatible, and their nanostructure is easily tunable with synthetic techniques. In this paper, we report the synthesis of a novel class of biomaterials from block copolymers containing a hydrophobic block of methyl methacrylate and a hydrophilic block of either acrylic acid, dimethyl acrylamide, or 2-hydroxyethyl methacrylate. The block copolymers were synthesized using a combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and click chemistry. Since the surface morphology is critical for successful cell growth, atomic force microscopy (AFM) studies were conducted for selected block copolymers. The topography, phase angle and friction maps were obtained in dry and physiological buffer environments to study the morphology. Results of AFM imaging identified the presence of polymer domains corresponding to the copolymer components. The distribution of nanoscale features in these block copolymers are comparable to those found on other surfaces that exhibit favorable cell adhesion and growth. In physiological buffer medium, the hydrophilic component of the block copolymer (acrylic acid or hydroxyethyl methacrylate) appear to be present in greater amounts on the surface as a consequence of water absorption and swelling. PMID:20207483

Schricker, Scott; Palacio, Manuel; Thirumamagal, B.T.S.; Bhushan, Bharat

2010-01-01

95

Morphological and biomolecular characterization of the neonatal olfactory bulb ensheathing cell line.  

PubMed

Cell transplantation therapy has raised a great interest in the perspective of its employment for nerve tissue repair. Among the various cell populations proposed, olfactory ensheathing glial cells have raised great interest over recent years, especially in the perspective of their employment for neural repair because of their homing capacity in both central and peripheral nervous system. This paper is aimed to provide an in vitro characterization of the NOBEC (neonatal olfactory bulb ensheathing cell) line that was obtained from primary cells dissociated from rat neonatal olfactory bulb (OB) and immortalized by retroviral transduction of SV40 large T antigen. Light and electron microscopy investigation showed that NOBECs are a homogeneous cell population both at structural and ultrastructural level. RT-PCR, Western blotting and immunocytochemistry showed that NOBECs express the glial markers S100, GFAP (Glial Fibrillar Acid Protein) and p75NGFR as well as NRG1 (neuregulin-1) and ErbB1-2-3 receptors; while they are negative for ErbB4. Yet, NOBECs exhibit a high proliferation and migration basal activity and can be transducted with vectors carrying GFP (green fluorescent protein) and NRG1 cDNA. Functional stimulation by means of NRG1-III-beta3 overexpression through viral transduction induced a significant increase in cell proliferation rate while it had no effect on cell migration. Altogether, these results show that NOBEC cell line retain glial features both morphologically and functionally, responding to the NRG1/ErbB-mediated gliotrophic stimulus, and represents thus a good tool for in vitro assays of glial cell manipulation and for in vivo experimental studies of glial cell transplantation in the central and peripheral nervous system. PMID:19786050

Audisio, Chiara; Raimondo, Stefania; Nicolino, Silvia; Gambarotta, Giovanna; Di Scipio, Federica; Macrì, Loredana; Montarolo, Francesca; Giacobini-Robecchi, Maria Giuseppina; Porporato, Paolo; Filigheddu, Nicoletta; Graziani, Andrea; Geuna, Stefano; Perroteau, Isabelle

2009-12-15

96

Electrophysiological characterization of spinal neurons in different models of diabetes type 1- and type 2-induced neuropathy in rats.  

PubMed

Diabetic polyneuropathy (DPN) is a devastating complication of diabetes. The underlying pathogenesis of DPN is still elusive and an effective treatment devoid of side effects presents a challenge. There is evidence that in type-1 and -2 diabetes, metabolic and morphological changes lead to peripheral nerve damage and altered central nociceptive transmission, which may contribute to neuropathic pain symptoms. We characterized the electrophysiological response properties of spinal wide dynamic range (WDR) neurons in three diabetic models. The streptozotocin (STZ) model was used as a drug-induced model of type-1 diabetes, and the BioBreeding/Worcester (BB/Wor) and Zucker diabetic fatty (ZDF) rat models were used for genetic DPN models. Data were compared to the respective control group (BB/Wor diabetic-resistant, Zucker lean (ZL) and saline-injected Wistar rat). Response properties of WDR neurons to mechanical stimulation and spontaneous activity were assessed. We found abnormal response properties of spinal WDR neurons in all diabetic rats but not controls. Profound differences between models were observed. In BB/Wor diabetic rats evoked responses were increased, while in ZDF rats spontaneous activity was increased and in STZ rats mainly after discharges were increased. The abnormal response properties of neurons might indicate differential pathological, diabetes-induced, changes in spinal neuronal transmission. This study shows for the first time that specific electrophysiological response properties are characteristic for certain models of DPN and that these might reflect the diverse and complex symptomatology of DPN in the clinic. PMID:25686525

Schuelert, N; Gorodetskaya, N; Just, S; Doods, H; Corradini, L

2015-04-16

97

Morphological changes of short-wavelength cones in the developing S334ter-3 Transgenic rat  

PubMed Central

The S334ter-3 rat is a transgenic model of retinal degeneration (RD) developed to express a rhodopsin mutation similar to that found in human retinitis pigmentosa. Due to this advantage over other models of RD, a few retina transplant studies have been reported on this animal model. Currently, no information is available on cone photoreceptor changes that occur in the S334ter RD model. In this study, we investigated the effect of RD on the morphology, distribution, and synaptic connectivity of short-wavelength cones (S-cones) during development of S334ter-3 rat retinas. At P21 RD retinas, the outer-nuclear layer was significantly narrower, while S-cones showed shortening of their segments and axons compared to control retinas. From P90 onward, S-opsin-immunoreactive cells appeared at the outer margin of the inner-nuclear layer of RD retinas. Double-labelling experiments showed these cells contained recoverin and cone arrestin. Furthermore, ultra-structure study showed that synaptic ribbons are conserved in the S-cone at P180 RD retinas. Although cell density of S-cones significantly dropped after P90, survival rates depended on the retinal region. Overall, the S334ter-3 RD model shows hallmarks of cone remodelling due to photoreceptor degeneration. PMID:20114037

Hombrebueno, Jose R.; Tsai, Melody M.; Kim, Hong-Lim; De Juan, Joaquin; Grzywacz, Norberto M.; Lee, Eun-Jin

2010-01-01

98

Morphological changes in the rat Sertoli cell induced by the microtubule poison carbendazim.  

PubMed

Early morphological changes in the rat Sertoli cell induced by the fungicide carbendazim (methyl-2-benzimidazole carbamate; MBC), a metabolite of benomyl, were examined. Adult rats were treated with single doses of MBC (400 mg/kg) or vehicle and examined by light and electron microscopy at 3 hr post-treatment. Sloughing of elongating spermatid clusters was observed in all stages of spermatogenesis, except for Stages III-V. Cleavage occurred near the apical region of the seminiferous epithelium where cytoplasmic processes of the Sertoli cell surround the heads of elongating spermatids. The cleaved cytoplasm remained attached to the sloughed spermatids and ectoplasmic specializations remained undamaged. Intact microtubules were observed in the apical Sertoli cell cytoplasm (including sloughed tissues) but were decreased in the body region, where aggregates of mitochondria were found. Cytoplasm near the cleavage site exhibited rarefaction, which was associated with swollen cisternae of endoplasmic reticulum. It appears that the mechanism of germ cell sloughing induced by MBC treatment involves the disruption of microtubules in the body region of the Sertoli cell, the retraction of cytoplasmic organelles and the swelling of endoplasmic reticulum. PMID:7886678

Nakai, M; Hess, R A

1994-12-01

99

Diets Rich in Saturated and Polyunsaturated Fatty Acids Induce Morphological Alterations in the Rat Ventral Prostate  

PubMed Central

Aim To evaluate the influence of dietary lipid quality on the body mass, carbohydrate metabolism and morphology of the rat ventral prostate. Materials and Methods Wistar rats were divided into four groups: SC (standard chow), HF-S (high-fat diet rich in saturated fatty acids), HF-P (high-fat diet rich in polyunsaturated fatty acids) and HF-SP (high-fat diet rich in saturated and polyunsaturated fatty acids). We analyzed body mass, fat mass deposits, plasma blood, insulin resistance and the ventral prostate structure. Results Groups that received high-fat diets were heavier and presented larger fat deposits than SC group. The HF-S and HF-SP groups had higher glucose, insulin and total cholesterol serum levels and insulin resistance compared with the SC. The acinar area, epithelium height and area density of the lumen were higher in the HF-SP than in the other groups. The epithelium area density and epithelial cell proliferation were greater in the HF-P and HF-SP than in the SC group. All of the groups that received high-fat diets had greater area density of the stroma, area density of smooth muscle cells and stromal cell proliferation compared with the SC group. Conclusion Diets rich in saturated and/or polyunsaturated fatty acids induced overweight. Independently of insulin resistance, polyunsaturated fatty acids increased prostate stromal and epithelial cell proliferation. Saturated fatty acids influenced only stromal cellular proliferation. These structural and morphometric alterations may be considered risk factors for the development of adverse remodeling process in the rat ventral prostate. PMID:25029463

Furriel, Angélica; Campos-Silva, Pamella; Silva, Paola Cariello Guedes Picarote; Costa, Waldemar Silva; Sampaio, Francisco José Barcellos; Gregório, Bianca Martins

2014-01-01

100

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

101

Morphological, Mechanical and Structural Characterization of Damselfly Wing  

NASA Astrophysics Data System (ADS)

The damselfly belongs to the same insect family as the dragonfly that inspired the development of Micro Air Vehicles (MAVs). Understanding the morphological, mechanical and structural properties of wings, veins and membranes of fly would provide guidelines to develop efficient MAVs. Lack of test methodologies inhibited the progress. The objective of this research was to develop the above methodologies and then measure the properties of veins, membranes and wings of damselflies. The research yielded four test methodologies: fluorescence spectroscopic analysis to map the morphology of vein; axial nanoindentation test to measure indentation properties; micro tension test to measure tensile properties of microscopic components; and a unique vibration test of wings to measure natural frequency, stiffness and air damping factor. Axial indentation test contrasts the transverse indentation used in the past, whose results were corrupted by surface roughness and flexibility of veins. Veins were found to be made of two layered, elliptical tubular members. The thickness of inner and outer layers was about 8 and 5 microm, respectively and corresponding indentation moduli were 8.42 and 16.00 GPa. The modulus of veins agreed with those of human bones. The tensile modulus and strength of veins ranged from 14 to 17 GPa and 232 to 285 MPa, respectively. The damselfly wing was found to vibrate under bending and torsional deformations, the natural frequency (in air) ranged from 130 to 178 Hz, the wing stiffness ranged from 0.18 to 0.30 N/m with the air damping ratio from 0.67 to 0.79. Pathway to develop a material of matching properties is also presented.

Talucdher, ABSM Rupan Ali

102

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

PubMed

Levonorgestrel, a derivative of progesterone, effectively protects women against unwanted pregnancy as an emergency contraceptive. Previous studies have not been successful in determining the mechanism by which levonorgestrel acts. In the present study we analysed cilia beat action and cilia morphology following 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 mucosal explants bathed in 5 ?mol/L levonorgestrel and those bathed in medium alone (P < 0.05). There was a tendency for CBF to decrease more in the ampulla than in isthmus, but there were no differences between the proliferative and secretory phases. In rat oviducts, levonorgestrel produced a similar reduction in 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 in the classic '9 + 2' structure of cilia following levonorgestrel treatment in either system. Thus, levonorgestrel reduces CBF without damaging cilia morphology. Decreases in CBF may indicate a pathological role for levonorgestrel in the transportation of the ovum and zygote in the fallopian tube. PMID:25399777

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

2015-02-01

103

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

104

Characterization of fibroblast-like cells from the rat olfactory bulb.  

PubMed

The isolation and characterization of stem cells from an alternative tissue is a subject of intensive investigation. In the present study, we have focused on the characterization of fibroblastic cells in olfactory bulb tissue of the rat. To this end, 4-6 week old rats were killed and their olfactory bulb tissue was dissected out. Olfactory bulb derived fibroblast-like cells were recovered by adhesion to cell culture plastic. The plastic adherent cultivated cells were induced to differentiate along osteoblastic, adipogenic and chondrogenic lineages. Furthermore, the expression of some surface antigens was investigated. We obtained purified cells with spindle shaped morphology in primary culture, which differentiated into mesenchymal lineages. These cells expressed CD29 and CD90 (Thy1.1) surface antigens, but not CD31, CD34 and CD45. Our results indicate that fibroblast-like cells from the olfactory bulb are mesenchymal stem cells in nature. Taken together, our data suggest that olfactory bulb tissue may constitute a new source of mesenchymal stem cells and could be used for the treatment of injury. PMID:18956328

Soleimani, Masoud; Nadri, Samad; Salehi, Mohammad; Sobhani, Aligholi; Hajarizadeh, Athena

2008-01-01

105

Effect of the environment on the dendritic morphology of the rat auditory cortex  

PubMed Central

The present study aimed to identify morphological correlates of environment-induced changes at excitatory synapses of the primary auditory cortex (A1). We used the Golgi-Cox stain technique to compare pyramidal cells dendritic properties of Sprague-Dawley rats exposed to different environmental manipulations. Sholl analysis, dendritic length measures, and spine density counts were used to monitor the effects of sensory deafness and an auditory version of environmental enrichment (EE). We found that deafness decreased apical dendritic length leaving basal dendritic length unchanged, whereas EE selectively increased basal dendritic length without changing apical dendritic length. On the contrary, deafness decreased while EE increased spine density in both basal and apical dendrites of A1 layer 2/3 (LII/III) neurons. To determine whether stress contributed to the observed morphological changes in A1, we studied neural morphology in a restraint-induced model that lacked behaviorally relevant acoustic cues. We found that stress selectively decreased apical dendritic length in the auditory but not in the visual primary cortex. Similar to the acoustic manipulation, stress-induced changes in dendritic length possessed a layer specific pattern displaying LII/III neurons from stressed animals with normal apical dendrites but shorter basal dendrites, while infragranular neurons (layers V and VI) displayed shorter apical dendrites but normal basal dendrites. The same treatment did not induce similar changes in the visual cortex, demonstrating that the auditory cortex is an exquisitely sensitive target of neocortical plasticity, and that prolonged exposure to different acoustic as well as emotional environmental manipulation may produce specific changes in dendritic shape and spine density. PMID:19771593

Bose, Mitali; Muñoz-Llancao, Pablo; Roychowdhury, Swagata; Nichols, Justin A.; Jakkamsetti, Vikram; Porter, Benjamin; Byrapureddy, Rajasekhar; Salgado, Humberto; Kilgard, Michael P.; Aboitiz, Francisco; Dagnino-Subiabre, Alexies; Atzori, Marco

2010-01-01

106

Effect of the environment on the dendritic morphology of the rat auditory cortex.  

PubMed

The present study aimed to identify morphological correlates of environment-induced changes at excitatory synapses of the primary auditory cortex (A1). We used the Golgi-Cox stain technique to compare pyramidal cells dendritic properties of Sprague-Dawley rats exposed to different environmental manipulations. Sholl analysis, dendritic length measures, and spine density counts were used to monitor the effects of sensory deafness and an auditory version of environmental enrichment (EE). We found that deafness decreased apical dendritic length leaving basal dendritic length unchanged, whereas EE selectively increased basal dendritic length without changing apical dendritic length. On the contrary, deafness decreased while EE increased spine density in both basal and apical dendrites of A1 Layer 2/3 (LII/III) neurons. To determine whether stress contributed to the observed morphological changes in A1, we studied neural morphology in a restraint-induced model that lacked behaviorally relevant acoustic cues. We found that stress selectively decreased apical dendritic length in the auditory but not in the visual primary cortex. Similar to the acoustic manipulation, stress-induced changes in dendritic length possessed a layer-specific pattern displaying LII/III neurons from stressed animals with normal apical dendrites but shorter basal dendrites, while infragranular neurons (Layers V and VI) displayed shorter apical dendrites but normal basal dendrites. The same treatment did not induce similar changes in the visual cortex, demonstrating that the auditory cortex is an exquisitely sensitive target of neocortical plasticity, and that prolonged exposure to different acoustic as well as emotional environmental manipulation may produce specific changes in dendritic shape and spine density. PMID:19771593

Bose, Mitali; Muñoz-Llancao, Pablo; Roychowdhury, Swagata; Nichols, Justin A; Jakkamsetti, Vikram; Porter, Benjamin; Byrapureddy, Rajasekhar; Salgado, Humberto; Kilgard, Michael P; Aboitiz, Francisco; Dagnino-Subiabre, Alexies; Atzori, Marco

2010-02-01

107

Morphological and topological characterization of coarsened dendritic microstructures  

NASA Astrophysics Data System (ADS)

Qualitative and quantitative characterization of the coarsening dendritic samples has been achieved. Five directionally solidified Al-15wt.%Cu samples were isothermally coarsened for 10, 90, 255, 536, and 964 minutes. Quantitative characterization included the analysis of interface shape distributions and the measurement of topological properties. Qualitatively, the interfacial normal distributions described the degree of directionality found in the microstructure. These results were then supplemented with phase-field calculations that used the experimental reconstructions as an initial condition. Measuring the principal curvatures scaled by the length scale, the inverse of the surface area per unit volume ( S-1v ), allowed for the creation of interface shape distributions (ISD) which provided the probability of having an interfacial patch of a given curvature range in the microstructure. The ISD of all coarsened samples indicated that cylindrical interfaces appeared in the 90-minute sample and remained for the later coarsened samples and that most of the interfacial patches were saddle-shaped. The appearance of a peak in the ISD indicated that the microstructure was not evolving in a self-similar manner, despite the linear relationship between S-1v and the cube root of coarsening time. The interfacial normals indicated that the microstructure of the earliest coarsened sample had a four-fold symmetry that disappeared for the later coarsened samples and that the majority of interfaces were parallel with the solidification direction. Topological characterization included the measurement of the scaled genus, number of handles, and the number of liquid particles as a function of coarsening time. The scaled genus decreased with coarsening time due to the simplification of the microstructure and the increased number of liquid droplets with coarsening time. Further characterization was achieved by using the three-dimensional reconstructions of the 10- and 90-minute coarsened samples as an initial condition to phase-field calculations. It was shown that the average flux in curvature space provided by the phase-field calculations can be used to describe qualitatively the evolution of the interface shape distributions during non-self-similar coarsening. Interfacial velocity calculated by the phase-field simulation aided in the discovery that liquid tubes are being created through topological singularities.

Mendoza, Roberto

108

MRI-based morphological modeling, synthesis and characterization of cardiac tissue-mimicking materials.  

PubMed

This study uses standard synthetic methodologies to produce tissue-mimicking materials that match the morphology and emulate the in vivo murine and human cardiac mechanical and imaging characteristics, with dynamic mechanical analysis, atomic force microscopy (AFM), scanning electron microscopy (SEM) and magnetic resonance imaging. In accordance with such aims, poly(glycerol sebacate) (PGS) elastomeric materials were synthesized (at two different glycerol (G)-sebacic (S) acid molar ratios; the first was synthesized using a G:S molar ratio of 2:2, while the second from a 2:5 G:S molar ratio, resulting in PGS2:2 and PGS2:5 elastomers, respectively). Unlike the synthesized PGS2:2 elastomers, the PGS2:5 materials were characterized by an overall mechanical instability in their loading behavior under the three successive loading conditions tested. An oscillatory response in the mechanical properties of the synthesized elastomers was observed throughout the loading cycles, with measured increased storage modulus values at the first loading cycle, stabilizing to lower values at subsequent cycles. These elastomers were characterized at 4 °C and were found to have storage modulus values of 850 and 1430 kPa at the third loading cycle, respectively, in agreement with previously reported values of the rat and human myocardium. SEM of surface topology indicated minor degradation of synthesized materials at 10 and 20 d post-immersion in the PBS buffer solution, with a noted cluster formation on the PGS2:5 elastomers. AFM nanoindentation experiments were also conducted for the measurement of the Young modulus of the sample surface (no bulk contribution). Correspondingly, the PGS2:2 elastomer indicated significantly decreased surface Young's modulus values 20 d post-PBS immersion, compared to dry conditions (Young's modulus = 1160 ± 290 kPa (dry) and 200 ± 120 kPa (20 d)). In addition to the two-dimensional (2D) elastomers, an integrative platform for accurate construction of three-dimensional tissue-mimicking models of cardiac anatomy from 2D MR images using rapid prototyping manufacturing processes was developed. For synthesized elastomers, doping strategies with two different concentrations of the MRI contrast agent Dotarem allowed independent and concurrent control of the imaging characteristics (contrast and relaxivity) during the synthetic process for increased contrast agent absorption, with tremendous potential for non-destructive in vivo use and applications to cardiovascular and cerebrovascular diseases. PMID:22406555

Kossivas, Fotis; Angeli, S; Kafouris, D; Patrickios, C S; Tzagarakis, V; Constantinides, C

2012-06-01

109

Antigenic, morphologic, and molecular characterization of new Ehrlichia risticii isolates.  

PubMed Central

Ehrlichia risticii causes an acute infectious disease in horses called Potomac horse fever. To investigate the biological diversity of E. risticii organisms, nine E. risticii isolates derived from the peripheral blood monocytes of clinically sick horses in Ohio and Kentucky during the summers of 1991 and 1993 were compared with Illinois and Virginia isolates originally obtained from horses in Maryland in 1984. Seven of the nine isolates (081, 606, 380, 679, As, Co, and Ov) formed large morulae (tightly packed inclusions of ehrlichial organisms). The remaining isolates, including 1984 isolates, were individually dispersed or formed small morulae in the cytoplasm of P388D1 cells. In Western blot (immunoblot) analysis with four equine and one rabbit polyclonal anti-E. risticii sera, these recent E. risticii isolates showed patterns of antigenic proteins distinct from those of the 1984 isolates and could be divided into three groups: (i) 081; (ii) 606, 022, 067, 380, and 679; and (iii) As, Co, and Ov. By indirect fluorescent antibody labeling with two panels of murine anti-E. risticii (Illinois and Maryland isolates) monoclonal antibodies, isolate 081 was not labeled with any of 20 monoclonal antibodies tested. The remaining isolates were not labeled with several monoclonal antibodies. The digestion pattern with one of the restriction enzymes, AvaII, of the PCR-amplified partial 16S rRNA gene of E. risticii from all Kentucky isolates (As, Co, and Ov) was different from that of Illinois, Virginia, and six Ohio isolates. These results indicate the presence of distinct variants of E. risticii which vary significantly in morphology, antigenic composition, and the base sequence of the 16S rRNA gene. Images PMID:7533780

Chaichanasiriwithaya, W; Rikihisa, Y; Yamamoto, S; Reed, S; Crawford, T B; Perryman, L E; Palmer, G H

1994-01-01

110

Characterization of melanophore morphology by fractal dimension analysis.  

PubMed

Fractal or focal dimension (FD) analysis is a valuable tool to identify physiologic stimuli at the cellular and tissue levels that allows for quantification of cell perimeter complexity. The FD analysis was determined on fluorescence images of caffeine- or epinephrine-treated (or untreated control) killifish Fundulus heteroclitus (Linneaus) melanophores in culture. Cell perimeters were indicated by rhodamine-phalloidin labeling of cortical microfilaments using box-counting FD analysis. Caffeine-treated melanophores displayed dispersed melanosomes in cells with less serrated edges and reduced FD and complexity. Complexity in epinephrine-treated cells was significantly higher than the caffeine-treated cells or in the control. Cytoarchitectural variability of the cell perimeter is expected because cells change shape when cued with agents. Epinephrine-treated melanophores demonstrated aggregated melanosomes in cells with more serrated edges, significantly higher FD and thus complexity. Melanophores not treated with caffeine or epinephrine produced variable distributions of melanosomes and resulted in cells with variably serrated edges and intermediate FD with a larger SE of the regression and greater range of complexity. Dispersion of melanosomes occurs with rearrangements of the cytoskeleton to accommodate centrifugal distribution of melanosomes throughout the cell and to the periphery. The loading of melanosomes onto cortical microfilaments may provide a less complex cell contour, with the even distribution of the cytoskeleton and melanosomes. Aggregation of melanosomes occurs with rearrangements of the cytoskeleton to accommodate centripetal distribution of melanosomes. The aggregation of melanosomes may contribute to centripetal retraction of the cytoskeleton and plasma membrane. The FD analysis is, therefore, a convenient method to measure contrasting morphologic changes within stimulated cells. PMID:15016306

Kimler, Victoria A; Tracy-Bee, Mary; Ollie, Candace D; Langer, Renee M; Montante, James M; Marks, Charles R C; Carl Freeman, D; Anton Hough, R; Taylor, John D

2004-04-01

111

Morphological and chemical characterization of microfabricated fibres for biological applications.  

PubMed

Monodisperse fibres and particulates of different materials with controllable three-dimensional shape, size and chemical composition are of interest in research on toxic respirable fibres as well as wear debris around orthopaedic implants. We have previously demonstrated the production of well-controlled, metal and oxide microfabricated fibres having dimensions 0.1 to 10 microm. While our previous results focused on how controlled fibres can be prepared by microfabrication methods, this paper evaluates property-production relationships for microfabricated fibres. Here we have briefly reviewed the production of 0.1 microm x 0.5 microm x 10 microm microfabricated fibres made by electron beam lithography from evaporated titanium or silicon oxide films using a double lift-off method. We have also analysed the properties of these fibres with respect to morphology and chemical composition, and how they are affected by variations in the production process. Two different solution types have been used to place fibres into liquid suspension and to clean and sterilize them for biological testing. One method involves the use of organic solvents; the other a hydroxide solution and water. While fibre dimensions appear to be material-specific, differences can be corrected for by compensation of the size of the lithographic pattern. Similarly the crystallinity of fibres is material-specific, as is to be expected of evaporated thin films, but should be possible to modify by varying deposition parameters or heat treating, for example. Of the cleaning methods used, the one using an aqueous hydroxide solution is preferred over solvent cleaning, as it is easier to perform and appears to be more effective at removing resist from the fibre suspension. PMID:15348746

Gold, J; Kasemo, B

1997-05-01

112

Morphological characterization of carbon-nanofiber-reinforced epoxy nanocomposites using ultra-small angle scattering  

SciTech Connect

Studies of the properties of nanocomposites reinforced with vapor-grown carbon nanofibers (VGCFs) can be found throughout the literature. Electrical, mechanical, viscoelastic, and rheological properties are just a few of the characteristics that have been well discussed. Although these properties depend on morphology, morphological characterization is rare. Due to its 2-dimensional nature, microscopy is of limited value when analyzing network morphologies. This work will show how the characterization of the three-dimensional geometry and network formation of VGCFs can be determined using ultra-small angle scattering techniques. Ultra-small angle x-ray and neutron scattering (USAXS and USANS) were used to characterize the morphology of carbon nanofibers suspended in epoxy. Using a simplified tube model, we estimate the dimensions of suspended fibers. The assumption of tubular fibers accounts for the increased surface area observed with USAXS that is not accounted for using a solid rod model. Furthermore, USANS was used to search for a structural signature associated with the electrical percolation threshold. USANS extends to longer dimensional scales than USAXS, which measures a smaller range of momentum transfer. To determine the electrical percolation threshold, AC impedance spectroscopy was employed to verify that an electrically conductive, percolated network forms at VGCNF loadings of 0.8% < CNF wt% < 1.2%. These values correlate with the USANS data, where a morphological transition is seen at {approx}1.2% loading.

Justice, R.S.; Anderson, D.P.; Brown, J.M.; Arlen, M.J.; Colleary, A.J.; Lafdi, K.; Schaefer, D.W. (UCIN); (AFRL)

2010-07-01

113

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

114

Characterization of status epilepticus induced by two organophosphates in rats  

PubMed Central

Organophosphates (OP) inhibit the enzyme cholinesterase and cause accumulation of acetylcholine, and are known to cause seizures and status epilepticus (SE) in humans. The animal models of SE caused by organophosphate analogs of insecticides are not well characterized. SE caused by OPs paraoxon and diisopropyl fluorophosphate (DFP) in rats was characterized by electroencephalogram (EEG), behavioral observations and response to treatment with the benzodiazepine diazepam administered at various stages of SE. A method for SE induction using intrahippocampal infusion of paraoxon was also tested. Infusion of 200 nmol paraoxon into the hippocampus caused electrographic seizures in 43/52 (82.7%) animals tested; and of these animals, 14/43 (30%) had self-sustaining seizures that lasted 4–18 hours after the end of paraoxon infusion. SE was also induced by peripheral subcutaneous injection of diisopropyl fluorophosphate (DFP, 1.25 mg/kg) or paraoxon (1.00 mg/kg) to rats pretreated with atropine (2 mg/kg) and 2-pralidoxime (2-PAM,50 mg/kg) 30 minutes prior to OP injection. SE occurred in 78% paraoxon–treated animals and in 79% of DFP-treated animals. Diazepam (10 mg/kg) was administered 10 min and 30 min after the onset of continuous EEG seizures induced by paraoxon and it terminated SE in a majority of animals at both time points. DFP-induced SE was terminated in 60% animals when diazepam was administered 10 minutes after the onset of continuous EEG seizure activity but diazepam did not terminate SE in any animal when it was administered 30 minutes after the onset of continuous seizures. These studies demonstrate that both paraoxon and DFP can induce SE in rats but refractoriness to diazepam is a feature of DFP induced SE. PMID:22578704

Todorovic, Marko; Cowan, Morgan; Balint, Corinne; Sun, Chengsan; Kapur, Jaideep

2012-01-01

115

Preliminary morphological and immunohistochemical changes in rat hippocampus following postnatal exposure to sodium arsenite.  

PubMed

The effects of arsenic exposure during rapid brain growth period (RBGP) (postnatal period 4-11) on pyramidal neurons of cornu ammonis (specifically CA1 and CA3 regions) and granule cells of dentate gyrus (DG) of rat hippocampus were studied. Wistar rat pups, subdivided into the control (group I) and the experimental groups (group II, III, and IV), received distilled water and sodium arsenite (aqueous solution of 1.0, 1.5, and 2.0 mg/kg body weight, respectively) by intraperitoneal (i.p.) route. On postnatal day (PND) 12, the animals were sacrificed and brain tissue obtained. Paraffin sections (8 ?m thick) stained with Cresyl Violet (CV) were observed for morphological and morphometric parameters. Arsenic induced programmed cell death (apoptosis) was studied using Terminal deoxyribonucleotidyl transferase mediated dUTP biotin Nick End Labeling (TUNEL) technique on the paraffin sections. Microscopy revealed decreased number and isolation of pyramidal neurons in superficial layers, misalignments of pyramidal cells in stratum pyramidale (SP) of CA1 and CA3 in experimental group III and IV, and presence of polymorphic cells in subgranular zone of ectal limb of dentate gyrus (suggestive of arsenic induced proliferation and migration of granule cells in the dentate gyrus). Morphometric assessments quantified and confirmed the microscopic findings. The mean nuclear area of pyramidal cells was increased and cell density was decreased in the CA1, CA3, and DG of experimental groups in comparison to the control group. Increase in the TUNEL positive cells in DG was observed in the experimental group IV, suggestive of increased apoptosis. These observations confirm vulnerability of pyramidal (CA1, CA3) and granule cells (DG) of hippocampus during RBGP. PMID:24082510

Kaler, Saroj; Dhar, Pushpa; Bhattacharya, Arnab; Mehra, Raj D

2013-05-01

116

Preliminary Morphological and Immunohistochemical Changes in Rat Hippocampus Following Postnatal Exposure to Sodium Arsenite  

PubMed Central

The effects of arsenic exposure during rapid brain growth period (RBGP) (postnatal period 4-11) on pyramidal neurons of cornu ammonis (specifically CA1 and CA3 regions) and granule cells of dentate gyrus (DG) of rat hippocampus were studied. Wistar rat pups, subdivided into the control (group I) and the experimental groups (group II, III, and IV), received distilled water and sodium arsenite (aqueous solution of 1.0, 1.5, and 2.0 mg/kg body weight, respectively) by intraperitoneal (i.p.) route. On postnatal day (PND) 12, the animals were sacrificed and brain tissue obtained. Paraffin sections (8 ?m thick) stained with Cresyl Violet (CV) were observed for morphological and morphometric parameters. Arsenic induced programmed cell death (apoptosis) was studied using Terminal deoxyribonucleotidyl transferase mediated dUTP biotin Nick End Labeling (TUNEL) technique on the paraffin sections. Microscopy revealed decreased number and isolation of pyramidal neurons in superficial layers, misalignments of pyramidal cells in stratum pyramidale (SP) of CA1 and CA3 in experimental group III and IV, and presence of polymorphic cells in subgranular zone of ectal limb of dentate gyrus (suggestive of arsenic induced proliferation and migration of granule cells in the dentate gyrus). Morphometric assessments quantified and confirmed the microscopic findings. The mean nuclear area of pyramidal cells was increased and cell density was decreased in the CA1, CA3, and DG of experimental groups in comparison to the control group. Increase in the TUNEL positive cells in DG was observed in the experimental group IV, suggestive of increased apoptosis. These observations confirm vulnerability of pyramidal (CA1, CA3) and granule cells (DG) of hippocampus during RBGP. PMID:24082510

Kaler, Saroj; Dhar, Pushpa; Bhattacharya, Arnab; Mehra, Raj D.

2013-01-01

117

Genetic and morphological characterization of the Physidae of South Carolina (Gastropoda: Pulmonata: Basommatophora),  

E-print Network

Genetic and morphological characterization of the Physidae of South Carolina (Gastropoda: Pulmonata of reproductive isolation have dis- tinguished three physid species in South Carolina: the cosmopol- itan Physa. A sample of 11 P. carolinae from five South Carolina populations averaged greater than 10% sequence

Dillon, Robert T.

118

Physiological and Morphological Characterization of Local Interneurons in the Drosophila Antennal Lobe  

E-print Network

- tory processing. Especially the AL in the fruit fly, Drosophila melanogaster, with all its#12;Physiological and Morphological Characterization of Local Interneurons in the Drosophila­1019, 2010. First published May 26, 2010; doi:10.1152/jn.00249.2010. The Drosophila antennal lobe (AL) has

Menzel, Randolf - Institut für Biologie

119

Characterization of network morphology in anion binding hydrogels used for wastewater remediation  

E-print Network

Characterization of network morphology in anion binding hydrogels used for wastewater remediation wastewater effluents. The sorbent used was crosslinked polyamine (PAA$HCl) polymeric hydrogels. The surface of crosslinking. q 2005 Elsevier Ltd. All rights reserved. Keywords: Hydrogel; Atomic force microscopy; Wastewater

Rubloff, Gary W.

120

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

121

Neuroepithelial bodies in the Fawn Hooded rat lung: morphological and neuroanatomical evidence for a sensory innervation.  

PubMed Central

The lungs of young Fawn Hooded (FH) rats contain neuroepithelial bodies (NEB) with a very dense innervation. They are covered by a unicellular layer of flattened Clara cells and their apices protrude slightly into the airway lumen. The NEB corpuscle cells are loaded with dense core vesicles and are potentially capable of secretion by basal exocytosis. Since they are exposed to the airspace by narrow pores between the covering Clara cells, they may be influenced by the composition of the inhaled air. Facilitated uptake of the secreted substances into the bloodstream is indicated by the presence of extensively fenestrated capillaries in the corium beneath the NEB. The NEB are richly innervated by nerve fibres which loop through the corpuscle and form 'en passant' nerve endings. Most of these are packed with mitochondria and are morphologically afferent nerve endings. A much rarer type of nerve ending contains cholinergic-type vesicles and is morphologically efferent. Since both types are often observed in cytoplasmic continuity, the secretory activity of the NEB may be locally modulated by axon reflexes. The nerve endings often display synaptic junctions with the NEB corpuscle cells, which are invariably oriented towards the central nervous system. The sensory nature of the NEB innervation was confirmed by the results of neuroanatomical experiments. Infranodose vagotomy led to degeneration and disappearance of ipsilateral NEB intracorpuscular nerve endings, while supranodose vagotomy had no significant effect. In contrast to these findings, the end bulbs of preganglionic nerve fibres synapsing with intrapulmonary ganglion cells degenerated and disappeared after both procedures of vagotomy. Therefore, the nerve endings observed in pulmonary NEB must be derived mainly from vagal nodose (i.e. sensory) ganglion cells. It is concluded that although their precise functional significance remains obscure, pulmonary NEB in the Fawn Hooded rat appear to be well adapted to act both as endocrine glands and receptor organs. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Fig. 12 Fig. 13 Fig. 14 PMID:8300432

van Lommel, A; Lauweryns, J M

1993-01-01

122

Gestational protein restriction induces alterations in placental morphology and mitochondrial function in rats during late pregnancy.  

PubMed

The placenta acts a regulator of nutrient composition and supply from mother to fetus and is the source of hormonal signals that affect maternal and fetal metabolism. Thus, appropriate development of the placenta is crucial for normal fetal development. We investigated the effect of gestational protein restriction (GPR) on placental morphology and mitochondrial function on day 19 of gestation. Pregnant dams were divided into two groups: normal (NP 17 % casein) or low-protein diet (LP 6 % casein). The placentas were processed for biochemical, histomorphometric and ultrastructural analysis. The integrity of rat placental mitochondria (RPM) isolated by conventional differential centrifugation was measured by oxygen uptake (Clark-type electrode). LP animals presented an increase in adipose tissue and triacylglycerol and a decrease in serum insulin levels. No alterations were observed in body, liver, fetus, or placenta weight. There was also no change in serum glucose, total protein, or lipid content. Gestational protein restriction had tissue-specific respiratory effects, with the observation of a small change in liver respiration (~13 %) and considerable respiratory inhibition in placenta samples (~37 %). The higher oxygen uptake by RPM in the LP groups suggests uncoupling between respiration and oxidative phosphorylation. In addition, ultrastructural analysis of junctional zone giant cells from LP placenta showed a disorganized cytoplasm, with loss of integrity of most organelles and intense vacuolization. The present results led us to hypothesize that GPR alters placental structure and morphology, induces sensitivity to insulin, mitochondrial abnormalities and suggests premature aging of the placenta. Further studies are needed to test this hypothesis. PMID:23884563

Rebelato, Hércules Jonas; Esquisatto, Marcelo Augusto Marreto; Moraes, Camila; Amaral, Maria Esmeria Corezola; Catisti, Rosana

2013-12-01

123

Low-level phenolic estrogen pollutants impair islet morphology and ?-cell function in isolated rat islets.  

PubMed

Phenolic estrogen pollutants, a class of typical endocrine-disrupting chemicals, have attracted public attention due to their estrogenic activities of imitating steroid hormone 17?-estradiol (E(2)) effects. Exposure to these pollutants may disrupt insulin secretion and be a risk factor for type 2 diabetes. In this study, we investigated the direct effects of phenolic estrogen diethylstilbestrol (DES), octylphenol (OP), nonylphenol (NP), and bisphenol A (BPA) on rat pancreatic islets in vitro, whose estrogenic activities were DES>NP>OP>BPA. Isolated ?-cells were exposed to E(2), DES, OP, NP, or BPA (0, 0.1, 0.5, 2.5, 25, and 250??g/l) for 24?h. Parameters of insulin secretion, content, and morphology of ?-cells were measured. In the glucose-stimulated insulin secretion test, E(2) and DES increased insulin secretion in a dose-dependent manner in a 16.7?mM glucose condition. However, for BPA, NP, or OP with lower estrogenic activity, the relationship between the doses and insulin secretion was an inverted U-shape. Moreover, OP, NP, or BPA (25??g/l) impaired mitochondrial function in ?-cells and induced remarkable swelling of mitochondria with loss of distinct cristae structure within the membrane, which was accompanied by disruption of mRNA expression of genes playing a key role in ?-cell function (Glut2 (Slc2a2), Gck, Pdx1, Hnf1?, Rab27a, and Snap25), and mitochondrial function (Ucp2 and Ogdh). Therefore, these phenolic estrogens can disrupt islet morphology and ?-cell function, and mitochondrial dysfunction is suggested to play an important role in the impairment of ?-cell function. PMID:22946080

Song, Liqiong; Xia, Wei; Zhou, Zhao; Li, Yuanyuan; Lin, Yi; Wei, Jie; Wei, Zhengzheng; Xu, Bing; Shen, Jie; Li, Weiyong; Xu, Shunqing

2012-11-01

124

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

125

A new method for characterization of domain morphology of polymer blends using RuO{sub 4} staining and LVSEM  

SciTech Connect

Ruthenium tetroxide (RuO{sub 4}) staining for TEM is a well proven technique for the characterization of crystalline polyolefins. Blend morphology has also been studied using RuO{sub 4} staining and LVSEM in the characterization of polyolefin blend morphology, specifically blends of polypropylene modified by the addition of elastomers or plastics. This method is often preferred over TEM for the characterization of blends and is applicable to many problems encountered in commercial and industrial laboratories including the analysis of domain morphology in molded parts, extruded films and fibers, failure analysis, and the analysis of layer morphology in certain coextruded films.

Brown, G.M.; Butler, J.H. [Exxon Chemical Company, Baytown, TX (United States)

1996-12-31

126

The Effect of Cochinchina momordica Seed Extract on Gastric Acid Secretion and Morphologic Change in Aged Rat Stomach  

PubMed Central

Background/Aims Cochinchina momordica seed extract (SK-MS10) has a gastric protective effect. We aimed to assess the effect of SK-MS10 on gastric acid secretion with morphologic changes in the aged rat. Methods Acid secretions were evaluated in the male F344 rats of four different ages (6-, 31-, 74-week, and 2-year). The 31-week-old rats were divided to three groups and continuously administered chow containing vehicle, SK-MS10 and lansoprazole, respectively. At the age of 74 weeks and 2 years, basal and stimulated acid was measured and the expression of mRNA and protein of H+-K+-ATPase were determined. The area of connective tissue of lamina propria was measured. Results Basal and stimulated gastric acid significantly decreased and connective tissue of lamina propria increased with age. The expression of mRNA and protein of H+-K+-ATPase significantly decreased with age. However, 74-week-old rats in the SK-MS10 group had higher stimulated gastric acid secretion than those in the vehicle and lansoprazole groups. In 2-year-old rats of SK-MS10 group, there was no increase of connective tissue. Conclusions As SK-MS10 kept the capacity of acid secretion as well as connective tissue area to comparable to young rats, it might valuable to perform further research regarding mechanism of SK-MS10 as an antiaging agent in the stomach. PMID:24073314

Jo, Hyun Jin; Nam, Ryoung Hee; Chang, Hyun; Kim, Joo-Hyon; Park, Ji Hyun; Kang, Jung Mook; Lee, Dong Ho; Jung, Hyun Chae

2013-01-01

127

Effects of an anabolic steroid and sprint training on selected histochemical and morphological observations in rat skeletal muscle types  

Microsoft Academic Search

Summary  The effects on selected histochemical and morphological parameters of anabolic steroid administration and of high-intensity sprint running, separately, and in combination, were studied in young adult male rats. Dianabol (methandrostenolone) 1 mg\\/day for 8 weeks had no significant effects on phosphorylase or glycogen staining intensities and on fiber area in skeletal muscles of either trained or sedentary animals. The program

Robert C. Hickson; William W. Heusner; Wayne D. Van Huss; James F. Taylor; Rexford E. Carrow

1976-01-01

128

Angiotensin Actions on the Isolated Rat Uterus during the Estrous Cycle: Influence of Resting Membrane Potential and Uterine Morphology  

Microsoft Academic Search

The involvement of AT1 and AT2 receptor subtypes in the response of the isolated rat uterus to angiotensin II (AngII) was studied throughout the estrous cycle. The AngII potency varied during the different estrous cycle phases, as indicated by significantly different pD2 values. No significant differences were observed in AngII metabolism among different estrous phases. Morphological analysis indicated that external

D. Accorsi-Mendonça; F. M. A. Corrêa; J. A. Anselmo-Franci; T. B. Paiva; A. M. de Oliveira

2002-01-01

129

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

130

Mitochondrial morphology and dynamics in hepatocytes from normal and ethanol-fed rats  

PubMed Central

Mitochondrial structure and function are central to cell physiology and are mutually interdependent. Mitochondria represent a primary target of the alcohol-induced tissue injury, particularly in the liver, where the metabolic effects of ethanol are predominant. However, the effect of ethanol on hepatic mitochondrial morphology and dynamics remain to be established. In the present work, we employed the organelle-targeted photoactivatable fluorescent protein technology and electron microscopy to study hepatic mitochondrial structure and dynamics. Hepatocytes in perfused liver as well as in primary cultures showed mostly discrete globular or short tubular mitochondria. The mitochondria showed few fusion events and little movement activity. By contrast, human hepatoma (HepG2)-derived VL-17A cells, expressing the major hepatic ethanol metabolizing enzymes, alcohol dehydrogenase and cytochrome P450 2E1, have elongated and interconnected mitochondria showing matrix continuity and many fusion events. Hepatocytes isolated from chronically ethanol-fed rats showed some increase in mitochondrial volume and exhibited a substantial suppression of mitochondrial dynamics. In VL-17A cells, prolonged ethanol exposure also caused decreased mitochondrial continuity and dynamics. Collectively, these results indicate that mitochondria in normal hepatocytes show relatively slow dynamics, which is very sensitive to suppression by ethanol exposure. PMID:22526459

Das, Sudipto; Hajnóczky, Nora; Antony, Anil Noronha; Csordás, György; Gaspers, Lawrence D.; Clemens, Dahn L.; Hoek, Jan B.

2013-01-01

131

Morphological study of the effects of ozone on rat lung. II. Long-term exposure  

SciTech Connect

To evaluate the morphological changes observed in animals after prolonged ozone exposure, 56 male rats were exposed to a high ambient level of ozone (0.5 ppm) 6 hr a day, 6 days a week, for 2, 3, 5, and 12 months and examined by light and electron microscopy. Bronchitis and peribronchitis were observed throughout the exposure periods, and connective tissue around the bronchi thickened as a result of fibrosis. Some bronchiolar ciliated cells were in a degenerated condition and others in a reparative phase. Hyperplastic nodules were not found in the bronchioles, but hyperplasia of the bronchiolar epithelium was observed. Hyperplasia of lymphoid nodules around small vessels was prominent after 2 months of exposure. After 3 months of exposure, alveolar ducts were lined by type 2 cells, and after 12 months, by the bronchiolar epithelium consisting of both ciliated and nonciliated cells. Alveolar macrophages accumulated in the centriacinar alveoli. Fibrous strands were seen to be deposited in alveolar ducts after 3 months, and in bronchioles after 5 months. This fibrosis was due to an increment in collagen fibers. The degree of fibrosis increased with the length of ozone exposure.

Hiroshima, K.; Kohno, T.; Ohwada, H.; Hayashi, Y.

1989-04-01

132

3D Reconstruction and Standardization of the Rat Vibrissal Cortex for Precise Registration of Single Neuron Morphology  

PubMed Central

The three-dimensional (3D) structure of neural circuits is commonly studied by reconstructing individual or small groups of neurons in separate preparations. Investigation of structural organization principles or quantification of dendritic and axonal innervation thus requires integration of many reconstructed morphologies into a common reference frame. Here we present a standardized 3D model of the rat vibrissal cortex and introduce an automated registration tool that allows for precise placement of single neuron reconstructions. We (1) developed an automated image processing pipeline to reconstruct 3D anatomical landmarks, i.e., the barrels in Layer 4, the pia and white matter surfaces and the blood vessel pattern from high-resolution images, (2) quantified these landmarks in 12 different rats, (3) generated an average 3D model of the vibrissal cortex and (4) used rigid transformations and stepwise linear scaling to register 94 neuron morphologies, reconstructed from in vivo stainings, to the standardized cortex model. We find that anatomical landmarks vary substantially across the vibrissal cortex within an individual rat. In contrast, the 3D layout of the entire vibrissal cortex remains remarkably preserved across animals. This allows for precise registration of individual neuron reconstructions with approximately 30 µm accuracy. Our approach could be used to reconstruct and standardize other anatomically defined brain areas and may ultimately lead to a precise digital reference atlas of the rat brain. PMID:23284282

Egger, Robert; Narayanan, Rajeevan T.; Helmstaedter, Moritz; de Kock, Christiaan P. J.; Oberlaender, Marcel

2012-01-01

133

Characterization of the cytosolic estrogen receptor in rat skeletal muscle.  

PubMed

A charcoal assay and the synthetic estrogen [6,7-3H]R 2858 (17 alpha-ethynyl-11 beta-methoxyestradiol-17 beta) were used to show that rat skeletal muscle cytosol contains an estrogen receptor, which was characterized with regard to association and dissociation rate-constants at several temperatures. The degradation kinetics was also studied, and was more rapid in the absence than in the presence of ligand. Association, dissociation and degradation were all temperature-dependent. The apparent equilibrium dissociation constant (Kd), however, was not temperature-dependent, and was about 0.1-1.0 nM, whether calculated from the rate constants or determined by Scatchard analysis. Estradiol-17 beta and R 2858 were compared as ligands for Scatchard analysis; the maximum number of binding sites being about the same (120 and 110 fmol/g tissue, respectively, but the Kd was lower for estradiol-17 beta (0.16 nM) than for R 2858 (0.73 nM). Ligand specificity studies (using [3H]R 2858 as well as [3H]estradiol-17 beta) showed that R 2858 binds to an estrogen receptor in rat skeletal muscle. The estrogen receptor interacted both with heparin and with DNA covalently coupled to agarose, and was eluted from either column by NaCl. Chromatography of crude cytosol on heparin-agarose or DNA-agarose lead to an at least 10-fold or 25-fold purification of the estrogen receptor, respectively. DNA-agarose chromatography or ammonium sulfate precipitation did not separate the estrogen receptor from the androgen or glucocorticoid receptors in rat muscle. PMID:7104393

Dahlberg, E

1982-07-16

134

Volitional Weight-Lifting in Rats Promotes Adaptation via Performance and Muscle Morphology prior to Gains in Muscle Mass  

PubMed Central

Investigation of volitional animal models of resistance training has been instrumental in our understanding of adaptive training. However, these studies have lacked reactive force measurements, a precise performance measure, and morphological analysis at a distinct phase of training – when initial strength gains precede muscle hypertrophy. Our aim was to expose rats to one month of training (70 or 700 g load) on a custom-designed weight-lifting apparatus for analysis of reactive forces and muscle morphology prior to muscle hypertrophy. Exclusively following 700 g load training, forces increased by 21% whereas muscle masses remained unaltered. For soleus (SOL) and tibialis anterior (TA) muscles, 700 g load training increased muscle fiber number per unit area by ?20% and decreased muscle fiber area by ?20%. Additionally, number of muscle fibers per section increased by 18% for SOL muscles. These results establish that distinct morphological alterations accompany early strength gains in a volitional animal model of load-dependent adaptive resistance training. PMID:25392697

Rader, Erik P; Miller, G Roger; Chetlin, Robert D; Wirth, Oliver; Baker, Brent A

2014-01-01

135

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

136

Establishment and Characterization of Rat Portal Myofibroblast Cell Lines  

PubMed Central

The major sources of scar-forming myofibroblasts during liver fibrosis are activated hepatic stellate cells (HSC) and portal fibroblasts (PF). In contrast to well-characterized HSC, PF remain understudied and poorly defined. This is largely due to the facts that isolation of rodent PF for functional studies is technically challenging and that PF cell lines had not been established. To address this, we have generated two polyclonal portal myofibroblast cell lines, RGF and RGF-N2. RGF and RGF-N2 were established from primary PF isolated from adult rat livers that underwent culture activation and subsequent SV40-mediated immortalization. Specifically, Ntpdase2/Cd39l1-sorted primary PF were used to generate the RGF-N2 cell line. Both cell lines were functionally characterized by RT-PCR, immunofluorescence, immunoblot and bromodeoxyuridine-based proliferation assay. First, immortalized RGF and RGF-N2 cells are positive for phenotypic myofibroblast markers alpha smooth muscle actin, type I collagen alpha-1, tissue inhibitor of metalloproteinases-1, PF-specific markers elastin, type XV collagen alpha-1 and Ntpdase2/Cd39l1, and mesenchymal cell marker ecto-5’-nucleotidase/Cd73, while negative for HSC-specific markers desmin and lecithin retinol acyltransferase. Second, both RGF and RGF-N2 cell lines are readily transfectable using standard methods. Finally, RGF and RGF-N2 cells attenuate the growth of Mz-ChA-1 cholangiocarcinoma cells in co-culture, as previously demonstrated for primary PF. Immortalized rat portal myofibroblast RGF and RGF-N2 cell lines express typical markers of activated PF-derived myofibroblasts, are suitable for DNA transfection, and can effectively inhibit cholangiocyte proliferation. Both RGF and RGF-N2 cell lines represent novel in vitro cellular models for the functional studies of portal (myo)fibroblasts and their contribution to the progression of liver fibrosis. PMID:25822334

Fausther, Michel; Goree, Jessica R.; Lavoie, Élise G.; Graham, Alicia L.; Sévigny, Jean; Dranoff, Jonathan A.

2015-01-01

137

Establishment and characterization of rat portal myofibroblast cell lines.  

PubMed

The major sources of scar-forming myofibroblasts during liver fibrosis are activated hepatic stellate cells (HSC) and portal fibroblasts (PF). In contrast to well-characterized HSC, PF remain understudied and poorly defined. This is largely due to the facts that isolation of rodent PF for functional studies is technically challenging and that PF cell lines had not been established. To address this, we have generated two polyclonal portal myofibroblast cell lines, RGF and RGF-N2. RGF and RGF-N2 were established from primary PF isolated from adult rat livers that underwent culture activation and subsequent SV40-mediated immortalization. Specifically, Ntpdase2/Cd39l1-sorted primary PF were used to generate the RGF-N2 cell line. Both cell lines were functionally characterized by RT-PCR, immunofluorescence, immunoblot and bromodeoxyuridine-based proliferation assay. First, immortalized RGF and RGF-N2 cells are positive for phenotypic myofibroblast markers alpha smooth muscle actin, type I collagen alpha-1, tissue inhibitor of metalloproteinases-1, PF-specific markers elastin, type XV collagen alpha-1 and Ntpdase2/Cd39l1, and mesenchymal cell marker ecto-5'-nucleotidase/Cd73, while negative for HSC-specific markers desmin and lecithin retinol acyltransferase. Second, both RGF and RGF-N2 cell lines are readily transfectable using standard methods. Finally, RGF and RGF-N2 cells attenuate the growth of Mz-ChA-1 cholangiocarcinoma cells in co-culture, as previously demonstrated for primary PF. Immortalized rat portal myofibroblast RGF and RGF-N2 cell lines express typical markers of activated PF-derived myofibroblasts, are suitable for DNA transfection, and can effectively inhibit cholangiocyte proliferation. Both RGF and RGF-N2 cell lines represent novel in vitro cellular models for the functional studies of portal (myo)fibroblasts and their contribution to the progression of liver fibrosis. PMID:25822334

Fausther, Michel; Goree, Jessica R; Lavoie, Élise G; Graham, Alicia L; Sévigny, Jean; Dranoff, Jonathan A

2015-01-01

138

Social Status and Sex Effects on Neural Morphology in Damaraland Mole-Rats, Fukomys damarensis  

Microsoft Academic Search

We previously reported that in a eusocial rodent, the naked mole-rat (Heterocephalus glaber), traditional neural sex differences were absent; instead, neural dimorphisms were associated with breeding status. Here we examined the same neural regions previously studied in naked mole-rats in a second eusocial species, the Damaraland mole-rat (Fukomys damarensis). Damaraland mole-rats live in social groups with breeding restricted to a

Jeff J. Anyan; Marianne L. Seney; Amanda Holley; Lynn Bengston; Bruce D. Goldman; Nancy G. Forger; Melissa M. Holmes

2011-01-01

139

Characterization of Nanocomposite filler Morphology using Ultra Small-Angle X-ray Scattering  

SciTech Connect

Loading polymer matrices with nanoscale fillers is widely believed to have the potential to push polymer properties to extreme values. Realization of anticipated properties, however, has proven elusive. Recent nanocomposite research suggests better characterization of the large-scale morphology will provide insight explaining these shortfalls. This work will present ultra-small angle X-ray scattering as a viable tool for elucidating the hierarchical filler morphology that exists within polymer nanocomposites. Scattering analysis tools developed by our group will be applied to scattering data from nanocomposites filled with carbon nanotubes, layered silicates, and colloidal silica. The relationship between imaging data and scattering data will be discussed in the context of filler dispersion. Finally, the impact of large-scale filler morphology on mechanical and electrical properties will be discussed.

Justice, Ryan S.; Schaefer, Dale W. (UCIN); (AFRL)

2010-10-22

140

Functional and Morphological Changes in Endocrine Pancreas following Cola Drink Consumption in Rats  

PubMed Central

Aim We report the effects of long-term cola beverage drinking on glucose homeostasis, endocrine pancreas function and morphology in rats. Methods Wistar rats drank: water (group W), regular cola beverage (group C, sucrose sweetened) or “light” cola beverage (group L, artificially sweetened). After 6 months, 50% of the animals in each group were euthanized and the remaining animals consumed water for the next 6 months when euthanasia was performed. Biochemical assays, insulinemia determination, estimation of insulin resistance (HOMA-IR), morphometry and immunohistochemistry evaluations were performed in pancreas. Results Hyperglycemia (16%, p<0.05), CoQ10 (coenzyme-Q10) decrease (?52%,p<0.01), strong hypertriglyceridemia (2.8-fold, p<0.01), hyperinsulinemia (2.4 fold, p<0.005) and HOMA-IR increase (2.7 fold, p<0.01) were observed in C. Group C showed a decrease in number of ? cells (?42%, p<0.01) and ? cells (?58%, p<0.001) and a moderate increase in ? cells’ size after wash-out (+14%, p<0.001). Group L showed reduction in ? cells’ size (?9%, p<0.001) and only after wash-out (L12) a 19% increase in size (p<0.0001) with 35% decrease in number of ? cells (p<0.01). Groups C and L showed increase in ?/?-cell ratio which was irreversible only in C (?/? = +38% in C6,+30% in C12, p<0.001vs.W6). Regular cola induced a striking increase in the cytoplasmic expression of Trx1 (Thioredoxin-1) (2.25-fold in C6 vs. W6; 2.7-fold in C12 vs. W12, p<0.0001) and Prx2 (Peroxiredoxin-2) (3-fold in C6 vs. W6; 2-fold in C12 vs. W12, p<0.0001). Light cola induced increase in Trx1 (3-fold) and Prx2 (2-fold) after wash-out (p<0.0001, L12 vs. W12). Conclusion Glucotoxicity may contribute to the loss of ? cell function with depletion of insulin content. Oxidative stress, suggested by increased expression of thioredoxins and low circulating levels of CoQ10, may follow sustained hyperglycemia. A likely similar panorama may result from the effects of artificially sweetened cola though via other downstream routes. PMID:25790473

2015-01-01

141

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

142

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

PubMed

In vitro primary hepatocyte systems typically elicit drug induction and toxicity responses at concentrations much higher than corresponding in vivo or clinical plasma C(max) 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

Dash, A; 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

2013-06-01

143

Mucous secretion in rat colonic mucosa during carcinogenesis induced by dimethylhydrazine. A morphological and histochemical study.  

PubMed Central

Our previous studies, in specimens of large intestine resected for carcinoma, have shown abnormal patterns of mucous secretion in areas of apparently "normal" mucosa, where goblet cells produce mainly sialomucins as compared with the true normal colonic mucosa in which sulphomucins predominate. In the present work, large bowel cancer was induced in rats by the administration of 1,2-dimethylhydrazine-2HCl (DMH). We attempted to study the sequential histological and secretory abnormalities which developed in the colonic epithelium during carcinogenesis, and to correlate these changes with those described above in the human. The microscopical and histological lesions observed in the colonic mucosa of DMH treated rats confirmed the findings of other authors and resembled the human colorectal cancer. The earliest changes detected were small foci of hyperplasia accompanied from the 6th week onwards by several foci of dysplasia. Carcinoma in situ appeared at the 15th week and finally invasive carcinoma developed from the 19th week onwards. Changes in the type of mucous secretion, with predominance of sialomucins, were observed in the majority of the areas showing mild to moderate dysplasia whilst the surrounding normal epithelium produced suphated material. Mucous depletion was a common feature in areas of severe dysplasia and carcinoma. These findings correlated well with the similar variations in the mucin composition observed in human colonic mucosa in carcinoma and further supported our previous hypothesis that mucin changes characterized by an increase in sialomucins might reflect early malignant transformation. If this hypothesis proved to be correct, the use of a simple method for the identification of mucins in large bowel biopsies would be of great help in detecting early malignancy. Images Fig. 9 Fig. 1 Fig. 3 Fig. 4 Fig. 5 p67-a Fig. 6 Fig. 7 Fig. 8 Fig. 10 Fig. 11 PMID:1174451

Filipe, M. I.

1975-01-01

144

Morphological, physiological, and molecular characterization of actinomycetes isolated from dry soil, rocks, and monument surfaces  

Microsoft Academic Search

In an extended study on the biodiversity of rock-dwelling bacteria, the colony and cell morphology, physiology, protein patterns,\\u000a and 16S rDNA sequences of 17 bacterial strains isolated from different surfaces of rocks, stones, and monuments and from various\\u000a geographical locations were characterized. All except one strain, which was found to be a Bacillus, were members of the order Actinomycetales. The

Martin Eppard; Wolfgang E. Krumbein; Cathrin Koch; Erhard Rhiel; James T. Staley; Erko Stackebrandt

1996-01-01

145

Characterization of PEO-based composite cathodes. I. Morphological, thermal, mechanical and electrical properties  

Microsoft Academic Search

This report describes the fabrication and characterization of polymer-based composite cathode membranes intended for use in polymer-electrolyte batteries operating at moderate temperatures (60--100 C). The present work is focused on the determination of morphological, thermal, mechanical, and electrical properties of PEO-based composite cathodes. The work was developed within the Advanced Lithium Polymer Electrolyte project (ALPE), an Italian integrated project devoted

G. B. Appetecchi; M. Carewska; F. Alessandrini; P. P. Prosini; S. Passerini

2000-01-01

146

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

147

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

148

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

149

DNA sequence of butyrylcholinesterase from the rat: expression of the protein and characterization of the properties of rat butyrylcholinesterase.  

PubMed

The rat is the model animal for toxicity studies. Butyrylcholinesterase (BChE), being sensitive to inhibition by some organophosphorus and carbamate pesticides, is a biomarker of toxic exposure. The goal of this work was to characterize the purified rat BChE enzyme. The cDNA sequence showed eight amino acid differences between the active site gorge of rat and human BChE, six clustered around the acyl binding pocket and two below the active site serine. A prominent difference in rat was the substitution of arginine for leucine at position 286 in the acyl pocket. Wild-type rat BChE, the mutant R286L, wild-type human BChE, and the mutant L286R were expressed in CHO cells and purified. Arg286 was found responsible for the resistance of rat BChE to inhibition by Triton X-100. Replacement of Arg286 with leucine caused the affinity for Triton X-100 to increase 20-fold, making it as sensitive as human BChE to inhibition by Triton X-100. Wild-type rat BChE had an 8- to 9-fold higher K(m) for the positively charged substrates butyrylthiocholine, acetylthiocholine, propionylthiocholine, benzoylcholine, and cocaine compared with wild-type human BChE. Wild-type rat BChE catalyzed turnover 2- to 7-fold more rapidly than human BChE, showing the highest turnover with propionylthiocholine (201,000 min(-1)). Human BChE does not reactivate spontaneously after inhibition by echothiophate, but rat BChE reactivates with a half-life of 4.3hr. Human serum contains 5mg/L of BChE and 0.01mg/L of AChE. Male rat serum contains 0.2mg/L of BChE and approximately 0.2mg/L of AChE. PMID:12110369

Boeck, Andreea Ticu; Schopfer, Lawrence M; Lockridge, Oksana

2002-06-15

150

Morphological and Metabolic Changes in the Nigro-Striatal Pathway of Synthetic Proteasome Inhibitor (PSI)-Treated Rats: A MRI and MRS Study  

PubMed Central

Systemic administration of a Synthetic Proteasome Inihibitor (PSI) in rats has been described as able to provide a model of Parkinson’s disease (PD), characterized by behavioral and biochemical modifications, including loss of dopaminergic neurons in the substantia nigra (SN), as assessed by post-mortem studies. With the present study we aimed to assess in-vivo by Magnetic Resonance (MR) possible morphological and metabolic changes in the nigro-striatal pathway of PSI-treated rats. 10 animals were subcutaneously injected with PSI 6.0 mg/kg dissolved in DMSO 100%. Injections were made thrice weekly over the course of two weeks. 5 more animals injected with DMSO 100% with the same protocol served as controls. The animals underwent MR sessions before and at four weeks after the end of treatment with either PSI or vehicle. MR Imaging was performed to measure SN volume and Proton MR Spectroscopy (1H-MRS) was performed to measure metabolites changes at the striatum. Animals were also assessed for motor function at baseline and at 4 and 6 weeks after treatment. Dopamine and dopamine metabolite levels were measured in the striata at 6 weeks after treatment. PSI-treated animals showed volumetric reduction of the SN (p<0.02) at 4 weeks after treatment as compared to baseline. Immunofluorescence analysis confirmed MRI changes in SN showing a reduction of tyrosine hydroxylase expression as compared to neuron-specific enolase expression. A reduction of N-acetyl-aspartate/total creatine ratio (p?=?0.05) and an increase of glutamate-glutamine-? amminobutirrate/total creatine were found at spectroscopy (p?=?0.03). At 6 weeks after treatment, PSI-treated rats also showed motor dysfunction compared to baseline (p?=?0.02), accompanied by dopamine level reduction in the striatum (p?=?0.02). Treatment with PSI produced morphological and metabolic modifications of the nigro-striatal pathway, accompanied by motor dysfunction. MR demonstrated to be a powerful mean to assess in-vivo the nigro-striatal pathway morphology and metabolism in the PSI-based PD animal model. PMID:23431380

Delli Pizzi, Stefano; Rossi, Cosmo; Di Matteo, Vincenzo; Esposito, Ennio; Guarnieri, Simone; Mariggiò, Maria Addolorata; Franciotti, Raffaella; Caulo, Massimo; Thomas, Astrid; Onofrj, Marco

2013-01-01

151

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

PubMed

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 dose of 2 g/kg every day for 28, 14 days after experimental animals done hyperlipidemia. The degenerative changes were observed in hyperlipidemic rats, light and electron microscopically. There was a significant increase in the levels of serum cholesterol, total lipid, alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), a significant decrease in the levels of liver tissue glutathione (GSH), a significant increase in the levels of tissue lipid peroxidation (LPO) in this group. On the other hand, the administration of Melissa officinalis L. extract reduced total cholesterol, total lipid, ALT, AST and ALP levels in serum, and LPO levels in liver tissue, moreover increased glutathione levels in the tissue. As a result, it was suggested that Melissa officinalis L. extract exerted an hypolipidemic effect and showed a protective effect on the liver of hyperlipidemic rats. PMID:15946812

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

2005-07-14

152

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. 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

153

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

154

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

155

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

156

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...

157

Morphologic and histologic abnormalities in female and male rats treated with anabolic steroids  

Microsoft Academic Search

A two-part study was performed to determine the ef fects of high doses of anabolic steroids on weight, appetite, and organ histology. Initially, 30 white Wistar rats, 15 males and 15 females, were treated weekly with either 0.52 cc of physiologic saline or nandrolone decanoate. After 6 weeks, female treated and control rats had comparable weight gains, but male treated

Janet A. Yu-Yahiro; Roger H. Michael; David V. Nasrallah; Brian Schofield

1989-01-01

158

Loss of perforated synapses in the dentate gyrus: morphological substrate of memory deficit in aged rats.  

PubMed Central

Most, but not all, aged rats exhibit a profound deficit in spatial memory when tested in a radial maze--a task known to depend on the integrity of the hippocampal formation. In this study, animals were divided into three groups based on their spatial memory capacity: young adult rats with good memory, aged rats with impaired memory, and aged rats with good memory. Memory-impaired aged animals showed a loss of perforated axospinous synapses in the dentate gyrus of the hippocampal formation in comparison with either young adults or aged rats with good memory. This finding suggests that the loss of perforated axospinous synapses in the hippocampal formation underlies the age-related deficit in spatial memory. Images PMID:3458260

Geinisman, Y; de Toledo-Morrell, L; Morrell, F

1986-01-01

159

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

160

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

161

Characterization of PbS with different morphologies produced using a cyclic microwave radiation  

NASA Astrophysics Data System (ADS)

PbS was produced from different lead (Pb(CH 3COO) 2·H 2O, PbCl 2·2.5H 2O, Pb(NO 3) 2) and sulfur (CH 3CSNH 2, CH 5N 3S, NH 2CSNH 2) sources in propylene glycol using a cyclic microwave radiation at different powers and prolonged times. PbS (cubic) was detected using X-ray diffraction (XRD) and selected area electron diffraction (SAED) techniques. The interpreted and simulated patterns are in good accord. Raman spectrometer revealed the presence of vibrations at 138, 273 and 439 cm -1. Different morphologies (nano-sized particles, hexapods, cubes, ferns and magic squares) were characterized using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). The product morphologies were influenced by the starting agents, microwave powers and prolonged times.

Phuruangrat, Anukorn; Thongtem, Titipun; Thongtem, Somchai

2008-09-01

162

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

163

Functional characterization of rat submaxillary gland muscarinic receptors using microphysiometry  

PubMed Central

Muscarinic cholinoceptors (MChR) in freshly dispersed rat salivary gland (RSG) cells were characterized using microphysiometry to measure changes in acidification rates. Several non-selective and selective muscarinic antagonists were used to elucidate the nature of the subtypes mediating the response to carbachol. The effects of carbachol (pEC50=5.74±0.02?s.e.mean; n=53) were highly reproducible and most antagonists acted in a surmountable, reversible fashion. The following antagonist rank order, with apparent affinity constants in parentheses, was noted: 4-DAMP (8.9)=atropine (8.9)>tolterodine (8.5)>oxybutynin (7.9)>S-secoverine (7.2)>pirenzepine (6.9)>himbacine (6.8)>AQ-RA 741 (6.6)>methoctramine (5.9). These studies validate the use of primary isolated RSG cells in microphysiometry for pharmacological analysis. These data are consistent with, and extend, previous studies using alternative functional methods, which reported a lack of differential receptor pharmacology between bladder and salivary gland tissue. The antagonist affinity profile significantly correlated with the profile at human recombinant muscarinic M3 and M5 receptors. Given a lack of antagonists that discriminate between M3 and M5, definitive conclusion of which subtype(s) is present within RSG cells cannot be determined. PMID:11264256

Meloy, Trena D; Daniels, Donald V; Hegde, Sharath S; Eglen, Richard M; Ford, Anthony P D W

2001-01-01

164

Characterization of new Alternaria alternata--specific rat monoclonal antibodies.  

PubMed

In this study, three different rat hybridoma cell lines secreting monoclonal antibodies (mAbs) recognizing the spores from Alternaria alternata, a plant pathogenic fungus, contaminant of food products and important cause of both allergic rhinitis and asthma, have been characterized. These three mAbs are all of IgM isotype. Two antibodies, A1 and F10, were cross-reactive antibodies recognizing spores from Alternaria, Cladosporium, Penicillium, Aspergillus and Stachybotrys genera, but not the yeasts Saccharomyces cerevisiae or Candida albicans. Competitive and sandwich assays demonstrated that these two mAbs were directed against the same or very close repetitive(s) epitope(s). A1-based sandwich ELISA efficiently detected this epitope in various mould (but not yeast)-soluble extracts prepared from strains grown in the laboratory. Moreover, this A1-based sandwich ELISA detected its cognate epitope in air and dust samples obtained from dwellings. The third antibody, E5, recognized only the spores of Alternaria and the phylogenetically very close Ulocladium botrytis. This E5 antibody is directed against a repetitive epitope found in Alternaria and Ulocladium laboratory extracts and can be used in a sandwich assay for the quantification of these moulds. Therefore, E5 antibody is a promising tool for the development of Alternaria-Ulocladium-specific immunoassays, while A1 and F10 could be interesting tools for the quantification of the total mould biomass. PMID:21892786

Denis, Olivier; Van Cauwenberge, Anne; Treutens, Greta; Es Saadi, Bouazza; Symoens, Françoise; Popovic, Nathalie; Huygen, Kris

2012-03-01

165

Acute doxorubicin cardiotoxicity: functional, metabolic, and morphologic alterations in the isolated, perfused rat heart.  

PubMed

The acute effects of doxorubicin on coronary perfusion and left ventricular pressures and intracellular phosphate metabolite levels, the latter obtained by 31P nuclear magnetic resonance, were measured simultaneously in isolated, isovolumic rat hearts (Langendorf preparation) perfused at constant flow. Nineteen experimental hearts were perfused for 70 min with oxygenated HEPES-buffered solution containing 6 mg/L doxorubicin. These were compared with 18 control hearts (C), perfused under identical conditions but without doxorubicin, by repeated measures analysis of variance. In the experimental group, coronary perfusion pressure steadily increased to 226.3 +/- 13.8% (mean +/- SEM) of initial levels (p less than 0.0001 vs. C). Because flow was constant, the increase in coronary perfusion pressure in experimental hearts indicates a greater than twofold increase in coronary resistance. Intracellular phosphocreatine and ATP decreased to 80.3 +/- 3.9% (p less than 0.005 vs. C) and 82.1 +/- 6.4% (p less than 0.05 vs. C), whereas inorganic phosphate increased to 149.7 +/- 19.1% (p less than 0.05 vs. C) of initial levels, respectively. Accompanying these changes, diastolic pressure steadily increased to 521.7 +/- 91.4% of initial levels (p less than 0.0001 vs. C). Developed pressure initially increased to 107.1 +/- 4.5% at 30 min, and thereafter decreased to 76.2 +/- 6.3% at 70 min (p less than 0.05 vs. C). Typical structural alterations in myocyte nuclei were noted. Cellular calcium was not increased in doxorubicin-exposed hearts. Thus, acute doxorubicin cardiotoxicity is characterized by an increase in coronary resistance and is closely correlated with alterations in ventricular function and a decrease in intracellular high-energy phosphate content.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2429080

Pelikan, P C; Weisfeldt, M L; Jacobus, W E; Miceli, M V; Bulkley, B H; Gerstenblith, G

1986-01-01

166

Characterization of the Han:SPRD rat model for hereditary polycystic kidney disease.  

PubMed

The Han:SPRD rat model for inherited polycystic kidney disease (PKD) was characterized (clinical parameters, morphology, immunohistochemistry and in situ hybridization). Homozygous animals died of uremia after three to four weeks with severe cystic transformation of virtually all nephrons and collecting ducts (serum urea: 616 +/- 195 mg/dl; kidney-to-body weight ratio: > 20%). In heterozygotes, slow progression of the disease led to death between the 12th and 21st month (median: 17 months; serum urea levels above 200 mg/dl). Kidney enlargement was moderate, and cysts were restricted to the cortex and outer medulla. Immunohistochemical markers showed that approximately 75% of the cysts were derived from the proximal tubule. Cystic transformation started in the proximal tubule with a sharp onset of basement membrane alteration and a loss of epithelial differentiation restricted to small focal areas. In these areas, alpha 1(IV) collagen and laminin B1 mRNA were enhanced as revealed by isotopic and non-isotopic in situ hybridization. Fibroblasts underlying the affected tubular portions were involved in matrix overexpression resulting in subepithelial accumulation of immunoreactive collagen IV and laminin. In later stages of cystic transformation distal nephron segments were affected as well. A reversal in epithelial polarity as judged from Na,K-ATPase-immunoreactivity was not observed. Renal immunoreactive renin-status was significantly decreased. Hematocrit was lowered in heterozygotes (40.4 +/- 5.8 vol% compared to 46.7 +/- 1.99 vol% in controls; P < 0.05) and total renal EPO mRNA was reduced to 36 +/- 14% of the mean value of control animals, whereas serum EPO levels were not significantly altered. We conclude that the Han:SPRD rat is a useful model for the study of human ADPKD since both diseases are similar in several aspects. The model is particularly suitable for the study of epithelial-mesenchymal interactions at the beginning of tubular cystic transformation. PMID:7933831

Schäfer, K; Gretz, N; Bader, M; Oberbäumer, I; Eckardt, K U; Kriz, W; Bachmann, S

1994-07-01

167

The Characterization of Obese Polycystic Ovary Syndrome Rat Model Suitable for Exercise Intervention  

PubMed Central

Objective To develop a new polycystic ovary syndrome (PCOS) rat model suitable for exercise intervention. Method Thirty six rats were randomly divided into three experimental groups: PCOS rats with high-fat diet (PF, n?=?24), PCOS rats with ordinary diet (PO, n?=?6), and control rats with ordinary diet (CO, n?=?6). Two kinds of PCOS rat model were made by adjustment diet structure and testosterone injection for 28 days. After a successful animal model, PF model rats were randomly assigned to three groups: exercise with a continuation of high-fat diet (PF-EF, n?=?6), sedentary with a continuation of high-fat diet (PF-SF, n?=?6), exercise with an ordinary diet (PF-EO, n?=?6). Fasting blood glucose (FBG) and insulin (FINS), estrogen (E2), progesterone (P), and testosterone (T) in serum were determined by RIA, and ovarian morphology was evaluated by Image-Pro plus 6.0. Results Body weight, Lee index, FINS increased significantly in PF rat model. Serum levels of E2 and T were significantly higher in PF and PO than in CO. Ovary organ index and ovarian areas were significant lower in PF than in CO. After intervention for 2 weeks, the levels of 1 h postprandial blood glucose (PBG1), 2 h postprandial blood glucose (PBG2), FINS and the serum levels of T decreased significantly in PF-EF rats and PF-EO rats. The ratio of FBG/FINS was significant higher in PF-EO rats than in PF-SF rats. Ovarian morphology showed that the numbers of preantral follicles and atretic follicles decreased significantly, and the numbers of antral follicles and corpora lutea increased significantly in the rats of PF-EF and PF-EO. Conclusion By combination of high-fat diet and testosterone injection, the obese PCOS rat model is conformable with the lifestyle habits of fatty foods and insufficient exercise, and has metabolic and reproductive characteristics of human PCOS. This model can be applied to study exercise intervention. PMID:24905232

Qiu, Shuwei; Jiang, Zhongli

2014-01-01

168

Application of BIB-SEM technology to characterize meso- and macropore morphology in coal  

NASA Astrophysics Data System (ADS)

Coalbeds are very heterogenous in composition, which in turn affects the connectivity and transport of fluids within the coal. The composition of a coalbed influences the pore structure. Pore structure as well as pore size distribution are two important parameters used in estimating reservoir properties. This study examines the morphology and distribution of macro- and mesopores in coal samples, using broad ion beam (BIB) milling to prepare relief- and damage-free polished surfaces of coal samples for high-resolution SEM imaging. The BIB-sections of a few square millimeters are not large enough to be statistically representative so that the results cannot be easily interpreted from a coal seam standpoint. Therefore, porosity was investigated as a function of maceral type to characterize pore morphologies. Macerals were selected from the vitrinite group, e.g. telocollinite, and from the inertinite group, e.g. fusinite and macrinite. The selected macerals were BIB-milled parallel to bedding and subsequently milled perpendicular to bedding. Pore morphology and pore size distribution was examined in each of the milled sections. For a vitrinite maceral type, we found no visible macroporosity within the resolution limits of the SE detector. Pore morphology in an inertinite maceral is dependent on the original maceral. Fusinite yields large, elongated pores (often filled with mineralization), while macrinite shows comparatively smaller, rounder pores. The BIB-milled sections perpendicular to bedding often showed an alternating sequence of bedding, with bed thicknesses varying between a few micrometers to greater than half a millimeter. The distribution of pores is also reflected by bed thickness in the sections perpendicular to bedding, with many pores being concentrated in association with the beds. The distribution of pore sizes follows a similar power law at different magnifications of the same BIB-milled surface. Our results show that micropores and macropores in coal belong to different populations, with different size distributions and morphologies. Furthermore, each maceral type studied yielded a different power law distribution. BIB-SEM imaging is a useful tool to study meso- and macropore morphology, especially in the size range between 10 nm and 10 ?m. In a future study, more maceral types should be examined for a better characterization of maceral porosity at different stages of coalification.

Giffin, Susan; Littke, Ralf; Klaver, Jop; Urai, Janos

2013-04-01

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

Purification, characterization, and biological compartmentalization of rat fetal antigen 1.  

PubMed

This study has established the rat as an animal model for the analysis of the biological role of fetal antigen 1 (FA1), a protein previously described in humans and mice. FA1 was purified from rat amniotic fluid by immunospecific affinity chromatography. Immunochemical identity between mouse and rat FA1 was established by crossed tandem immunoelectrophoresis. Molecular size was analyzed by mass spectrometry (33 kDa). The amino acid composition was determined, and the amino acid sequence was analyzed. The overall amino acid composition and sequence of the 28 first N-terminal amino acids were identical to the corresponding parts of rat preadipocyte factor 1 and rat adrenal zona glomerulosa protein. Extensive sequence similarity was found between rat and mouse FA1 (86%) and between rat and human FA1 (82%). The concentration of FA1 in fetal serum, maternal serum, urine, and amniotic fluid in rats was determined using an ELISA. The highest concentrations were found in fetal serum and amniotic fluid around Day 18 of pregnancy. This is the first report on the physicochemical characteristics and compartmentalization of rat FA1. PMID:10859238

Carlsson, H E; Persdotter-Hedlund, G; Fries, E; Eriksson, U J; Hau, J

2000-07-01

171

Toxic Effects of Maternal Zearalenone Exposure on Intestinal Oxidative Stress, Barrier Function, Immunological and Morphological Changes in Rats  

PubMed Central

The present study was conducted to investigate the effects of maternal zearalenone (ZEN) exposure on the intestine of pregnant Sprague-Dawley (SD) rats and its offspring. Ninety-six pregnant SD rats were randomly divided into four groups and were fed with diets containing ZEN at concentrations of 0.3 mg/kg, 48.5 mg/kg, 97.6 mg/kg or 146.0 mg/kg from gestation days (GD) 1 to 7. All rats were fed with mycotoxin-free diet until their offspring were weaned at three weeks of age. The small intestinal fragments from pregnant rats at GD8, weaned dams and pups were collected and studied for toxic effects of ZEN on antioxidant status, immune response, expression of junction proteins, and morphology. The results showed that ZEN induced oxidative stress, affected the villous structure and reduced the expression of junction proteins claudin-4, occludin and connexin43 (Cx43) in a dose-dependent manner in pregnant rats. Different effects on the expression of cytokines were also observed both in mRNA and protein levels in these pregnant groups. Ingestion of high levels of ZEN caused irreversible damage in weaned dams, such as oxidative stress, decreased villi hight and low expression of junction proteins and cytokines. Decreased expression of jejunal interleukin-8 (IL-8) and increased expression of gastrointestinal glutathione peroxidase (GPx2) mRNA were detected in weaned offspring, indicating long-term damage caused by maternal ZEN. We also found that the Nrf2 expression both in mRNA and protein levels were up-regulated in the ZEN-treated groups of pregnant dams and the high-dose of ZEN group of weaned dams. The data indicate that modulation of Nrf2-mediated pathway is one of mechanism via which ZEN affects gut wall antioxidant and inflammatory responses. PMID:25180673

Liu, Min; Gao, Rui; Meng, Qingwei; Zhang, Yuanyuan; Bi, Chongpeng; Shan, Anshan

2014-01-01

172

Lesion classification on breast MRI through topological characterization of morphology over time  

NASA Astrophysics Data System (ADS)

Morphological characterization of lesions on dynamic breast MRI exams through texture analysis has typically involved the computation of gray-level co-occurrence matrices (GLCM), which serve as the basis for second order statistical texture features. This study aims to characterize lesion morphology through the underlying topology and geometry with Minkowski Functionals (MF) and investigate the impact of using such texture features extracted dynamically over a time series in classifying benign and malignant lesions. 60 lesions (28 malignant & 32 benign) were identified and annotated by experienced radiologists on 54 breast MRI exams of female patients where histopathological reports were available prior to this investigation. 13 GLCM-derived texture features and 3 MF features were then extracted from lesion ROIs on all five post-contrast images. These texture features were combined into high dimensional texture feature vectors and used in a lesion classification task. A fuzzy k-nearest neighbor classifier was optimized using random sub-sampling cross-validation for each texture feature and the classification performance was calculated on an independent test set using the area under the ROC curve (AUC); AUC distributions of different features were compared using a Mann- Whitney U-test. The MF feature 'Area' exhibited significantly improvements in classification performance (p<0.05) when compared to all GLCM-derived features while the MF feature 'Perimeter' significantly outperformed 12 out of 13 GLCM features (p<0.05) in the lesion classification task. These results show that dynamic texture tracking of morphological characterization that relies on topological texture features can contribute to better lesion character classification.

Nagarajan, Mahesh B.; Huber, Markus B.; Schlossbauer, Thomas; Ray, Lawrence A.; Krol, Andrzej; Wismüller, Axel

2011-03-01

173

Microangiopathy and visual deficits characterize the retinopathy of a spontaneously hypertensive rat model with type 2 diabetes and metabolic syndrome.  

PubMed

Retinopathy has been increasing in prevalence as a consequence of type 2 diabetes and a cluster of coexisting risk factors characterized as the metabolic syndrome. However, the combined effects of these conditions on the retina are poorly understood. Therefore, we focused on the spontaneously hypertensive corpulent rat (SHR/N-cp), a model with type 2 diabetes, obesity and features of the metabolic syndrome to characterize retinal changes at a structural and functional level. SHR/N-cp males at 4 and 8 months of age were used in this study. Metabolic parameters and blood pressure were measured by standard methods. Morphology was investigated by histological techniques supplemented by nicotinamide adenine dinucleotide phosphate-diaphorase staining of whole mounts and fluorescein angiography to analyze the retinal vasculature. The in vivo function of the retina was examined by electroretinography (ERG). Obese SHR/N-cp rats were hypertensive and showed significant increases in body weight, serum levels of glucose, triglycerides, total cholesterol and urinary glucose excretion compared with lean controls (P < 0.01 for each). Histology indicated an overall intact integrity of the retina and aspects of microangiopathy in obese SHR/N-cp rats. ERG revealed intact processing of light signals but significantly decreased amplitudes of b-waves for all (P < 0.01) and of a-waves for some examined light intensities (P < 0.05). Oscillatory potentials were significantly protracted (P < 0.01), whereas amplitudes were not reduced. Microangiopathy and electroretinographic deficits combine to produce an early non-proliferative retinopathy phenotype in the obese SHR/N-cp rats. Thus, this model represents a valuable experimental tool to obtain further insights into the mechanisms of retinopathy in the context of obesity, type 2 diabetes and metabolic syndrome. PMID:20927114

Huber, Matthias; Heiduschka, Peter; Ziemssen, Focke; Bolbrinker, Juliane; Kreutz, Reinhold

2011-01-01

174

Effectiveness of morphological and spectral heartbeat characterization on arrhythmia clustering for Holter recordings  

NASA Astrophysics Data System (ADS)

Heartbeat characterization is an important issue in cardiac assistance diagnosis systems. In particular, wide sets of features are commonly used in long term electrocardiographic signals. Then, if such a feature space does not represent properly the arrhythmias to be grouped, classification or clustering process may fail. In this work a suitable feature set for different heartbeat types is studied, involving morphology, representation and time-frequency features. To determine what kind of features generate better clusters, feature selection procedure is used and assessed by means clustering validity measures. Then the feature subset is shown to produce fine clustering that yields into high sensitivity and specificity values for a broad range of heartbeat types.

Castro-Hoyos, Cristian; Peluffo-Ordóñez, Diego Hernán.; Rodríguez-Sotelo, Jose Luis; Castellanos-Domínguez, Germán.

2015-01-01

175

Morphological characterization of cells in concentrated suspensions using multispectral diffuse optical tomography.  

PubMed

Based on a non-spherical model of particle scattering, we investigate the capabilities and limitations of a T-matrix based inverse algorithm to morphologically characterize cells in concentrated suspensions. Here the cells are modeled as randomly orientated spheroidal particles with homogenous dielectric properties and suspended in turbid media. The inverse algorithm retrieves the geometrical parameters and the concentration of cells simultaneously by inverting the reduced scattering coefficient spectra obtained from multispectral diffuse optical tomography (MS-DOT). Both round and spheroidal cells are tested and the role of multiple and higher order scattering of particles on the performance of the algorithm is evaluated using different concentrations of cells. PMID:23372258

Hajihashemi, Mohammad Reza; Li, Xiaoqi; Jiang, Huabei

2012-10-01

176

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

177

Pirfenidone and candesartan ameliorate morphological damage in mild chronic antiGBM nephritis in rats  

Microsoft Academic Search

Background. The antifibrotic substance pirfenidone and the angiotensin II type I receptor antagonist candesartan cilexetil, given alone and in combination, were tested in rats with chronic anti-glomerular base- ment membrane glomerulonephritis (anti-GBM GN). Methods. Male Wistar rats with anti-GBM GN were treated for 8 weeks with candesartan (4 mg\\/kg body weight\\/day), pirfenidone (500 mg\\/kg body weight\\/day) or a combination of

Sabine Leh; Øyvind Vaagnes; Solomon B. Margolin; Bjarne M. Iversen; Terje Forslund

2004-01-01

178

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

179

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

SciTech Connect

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{sup ?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 LD{sub 50} 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; Awang, Mat Rasol; Mohamad, Azhar; Mutaat, Hassan Hamdani; Maskom, Mohd Meswan [Bioprocess Group, Agrotechnology and Biosciences Division, Malaysian Nuclear Agency, Bangi 43600, Selangor (Malaysia); Daud, Fauzi; Senafi, Sahidan [School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor (Malaysia)

2014-09-03

180

Morphological and electrophysiological features of motor neurons and putative interneurons in the dorsal vagal complex of rats and mice  

PubMed Central

The dorsal motor nucleus of the vagus (DMV) contains preganglionic motor neurons that control viscera along the subdiaphragmatic digestive tract, but may also contain neurons that do not project to the viscera. Neurons that expressed EGFP 60-72 h subsequent to PRV-152 inoculation of vagal terminals in the stomach wall were targeted for whole-cell patch-clamp recording and biocytin filling in transverse brainstem slices from rats and their quantitative morphological and electrophysiological characteristics were compared with uninfected cells. Over 90% of PRV-152 labeled neurons were also labeled subsequent to intraperitoneal injection of FluoroGold, indicating most were preganglionic motor neurons. In reconstructed neurons with an identifiable axon trajectory, two cellular subtypes were distinguished. The axon projected ventrolaterally from the DMV in 44 of 49 cells and these were likely to be vagal motor neurons. Axons of other neurons ramified within the nucleus tractus solitarius (NTS) or DMV. These cells were smaller and otherwise morphologically distinct from putative motor neurons. Transgenic mice with GFP-expressing inhibitory neurons (i.e., GIN mice) were used to identify a GABAergic subset vagal neurons. These neurons had locally-ramifying axons and formed a morphologically distinct subset of DMV cells, which were similar in size and axon trajectory to GABAergic neurons in the NTS. Most neurons in the DMV therefore possess morphological features of motor neurons, but locally projecting cells and inhibitory neurons with distinct morphological features are also found within the DMV. These cells likely contribute to regulation of vagal function. PMID:19619517

Gao, Hong; Glatzer, Nicholas R.; Williams, Kevin W.; Derbenev, Andrei V.; Liu, Dan; Smith, Bret N.

2009-01-01

181

Electroacupuncture improves microcirculation and neuronal morphology in the spinal cord of a rat model of intervertebral disc extrusion  

PubMed Central

Most studies on spinal cord neuronal injury have focused on spinal cord tissue histology and the expression of nerve cell damage and repair-related genes. The importance of the microcirculation is often ignored in spinal cord injury and repair research. Therefore, in this study, we established a rat model of intervertebral disc extrusion by inserting a silica gel pad into the left ventral surface of T13. Electroacupuncture was used to stimulate the bilateral Zusanli point (ST36) and Neiting point (ST44) for 14 days. Compared with control animals, blood flow in the first lumbar vertebra (L1) was noticeably increased in rats given electroacupuncture. Microvessel density in the T13 segment of the spinal cord was increased significantly as well. The number of normal neurons was higher in the ventral horn of the spinal cord. In addition, vacuolation in the white matter was lessened. No obvious glial cell proliferation was visible. Furthermore, hindlimb motor function was improved significantly. Collectively, our results suggest that electroacupuncture can improve neuronal morphology and microcirculation, and promote the recovery of neurological functions in a rat model of intervertebral disc extrusion.

Jiang, Dai-xun; Lu, Zhi-song; Li, Ge-bin; Sun, Sheng-yong; Mu, Xiang; Lee, Peter; Chen, Wu

2015-01-01

182

Multiscale analysis of morphology and mechanics in tail tendon from the ZDSD rat model of type 2 diabetes.  

PubMed

Type 2 diabetes (T2D) impacts multiple organ systems including the circulatory, renal, nervous and musculoskeletal systems. In collagen-based tissues, one mechanism that may be responsible for detrimental mechanical impacts of T2D is the formation of advanced glycation end products (AGEs) leading to increased collagen stiffness and decreased toughness, resulting in brittle tissue behavior. The purpose of this study was to investigate tendon mechanical properties from normal and diabetic rats at two distinct length scales, testing the hypothesis that increased stiffness and strength and decreased toughness at the fiber level would be associated with alterations in nanoscale morphology and mechanics. Individual fascicles from female Zucker diabetic Sprague-Dawley (ZDSD) rats had no differences in fascicle-level mechanical properties but had increased material-level strength and stiffness versus control rats (CD). At the nanoscale, collagen fibril D-spacing was shifted towards higher spacing values in diabetic ZDSD fibrils. The distribution of nanoscale modulus values was also shifted to higher values. Material-level strength and stiffness from whole fiber tests were increased in ZDSD tails. Correlations between nanoscale and microscale properties indicate a direct positive relationship between the two length scales, most notably in the relationship between nanoscale and microscale modulus. These findings indicate that diabetes-induced changes in material strength and modulus were driven by alterations at the nanoscale. PMID:24360194

Gonzalez, Armando Diaz; Gallant, Maxime A; Burr, David B; Wallace, Joseph M

2014-02-01

183

Morphological Evidence that Luteinizing Hormone-Releasing Hormone Neurons Participate in the Suppression by Estradiol of Pituitary Luteinizing Hormone Secretion in Ovariectomized Rats  

Microsoft Academic Search

Morphological characteristics of LHRH neurons identified by immunocytochemistry were studied using light and electron microscopy in female rats in which estradiol was replaced at the time of ovariectomy (‘pseudo-intact’ rats) or 3 weeks after ovariectomy (long-term ovariectomized, estradiol-treated). While estradiol levels were equivalent in these two groups, the rise in LH after ovariectomy was prevented by the immediate administration in

Joan C. King; Edythe L. P. Anthony; David A. Damassa; Karen E. Elkind-Hirsch

1987-01-01

184

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. PMID:25625048

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

2014-01-01

185

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

186

NMDA receptor-mediated pilocarpine-induced seizures: characterization in freely moving rats by microdialysis  

PubMed Central

Pilocarpine administration has been used as an animal model for temporal lobe epilepsy since it produces several morphological and synaptic features in common with human complex partial seizures. Little is known about changes in extracellular neurotransmitter concentrations during the seizures provoked by pilocarpine, a non-selective muscarinic agonist. Focally evoked pilocarpine-induced seizures in freely moving rats were provoked by intrahippocampal pilocarpine (10?mM for 40?min at a flow rate of 2??l min?1) administration via a microdialysis probe. Concomitant changes in extracellular hippocampal glutamate, ?-aminobutyric acid (GABA) and dopamine levels were monitored and simultaneous electrocorticography was performed. The animal model was characterized by intrahippocampal perfusion with the muscarinic receptor antagonist atropine (20?mM), the sodium channel blocker tetrodotoxin (1??M) and the N-methyl-D-aspartate (NMDA) receptor antagonist MK-801 (dizocilpine maleate, 100??M). The effectiveness of locally (600??M) or systemically (10?mg kg?1 day?1) applied lamotrigine against the pilocarpine-induced convulsions was evaluated. Pilocarpine initially decreased extracellular hippocampal glutamate and GABA levels. During the subsequent pilocarpine-induced limbic convulsions extracellular glutamate, GABA and dopamine concentrations in hippocampus were significantly increased. Atropine blocked all changes in extracellular transmitter levels during and after co-administration of pilocarpine. All pilocarpine-induced increases were completely prevented by simultaneous tetrodotoxin perfusion. Intrahippocampal administration of MK-801 and lamotrigine resulted in an elevation of hippocampal dopamine levels and protected the rats from the pilocarpine-induced seizures. Pilocarpine-induced convulsions developed in the rats which received lamotrigine perorally. Pilocarpine-induced seizures are initiated via muscarinic receptors and further mediated via NMDA receptors. Sustained increases in extracellular glutamate levels after pilocarpine perfusion are related to the limbic seizures. These are arguments in favour of earlier described NMDA receptor-mediated excitotoxicity. Hippocampal dopamine release may be functionally important in epileptogenesis and may participate in the anticonvulsant effects of MK-801 and lamotrigine. The pilocarpine-stimulated hippocampal GABA, glutamate and dopamine levels reflect neuronal vesicular release. PMID:9249254

Smolders, Ilse; Khan, Ghous M; Manil, Jacqueline; Ebinger, Guy; Michotte, Yvette

1997-01-01

187

Electrophysiological and morphological properties of neurons in the prepositus hypoglossi nucleus that express both ChAT and VGAT in a double-transgenic rat model.  

PubMed

Although it has been proposed that neurons that contain both acetylcholine (ACh) and ?-aminobutyric acid (GABA) are present in the prepositus hypoglossi nucleus (PHN), these neurons have not been characterized because of the difficulty in identifying them. In the present study, PHN neurons that express both choline acetyltransferase and the vesicular GABA transporter (VGAT) were identified using double-transgenic rats, in which the cholinergic and inhibitory neurons express the fluorescent proteins tdTomato and Venus, respectively. To characterize the neurons that express both tdTomato and Venus (D+ neurons), the afterhyperpolarization (AHP) profiles and firing patterns of these neurons were investigated via whole-cell recordings of brainstem slice preparations. Regarding the three AHP profiles and four firing patterns that the D+ neurons exhibited, an AHP with an afterdepolarization and a firing pattern that exhibited a delay in the generation of the first spike were the preferential properties of these neurons. In the three morphological types classified, the multipolar type that exhibited radiating dendrites was predominant among the D+ neurons. Immunocytochemical analysis revealed that the VGAT-immunopositive axonal boutons that expressed tdTomato were primarily located in the dorsal cap of inferior olive (IO) and the PHN. Although the PHN receives cholinergic inputs from the pedunculopontine tegmental nucleus and laterodorsal tegmental nucleus, D+ neurons were absent from these brain areas. Together, these results suggest that PHN neurons that co-express ACh and GABA exhibit specific electrophysiological and morphological properties, and innervate the dorsal cap of the IO and the PHN. PMID:25808645

Saito, Yasuhiko; Zhang, Yue; Yanagawa, Yuchio

2015-04-01

188

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

189

Mammary gland morphology and gene expression differ in female rats treated with 17?-estradiol or fed soy protein isolate.  

PubMed

Soy foods have been suggested to have both positive health benefits and potentially adverse effects as a result of their content of phytoestrogens. However, studies on the estrogenicity of soy foods are lacking. Here we directly compared the effects of soy protein isolate (SPI), the protein in soy infant formula, with those of 17?-estradiol (E2), on global gene expression profiles and morphology in the female rat mammary gland. Rats were fed AIN-93G diets containing casein or SPI beginning on postnatal d 30. Rats were ovariectomized on postnatal d 50 and treated with 5 ?g/kg/d E2 or vehicle for 14 d. Microarray analysis revealed that E2 treatment altered expression of 780 genes more than or equal to 2-fold (P < 0.05), whereas SPI feeding altered expression of only 53 genes more than or equal to 2-fold. Moreover, the groups had only 10 genes in common to increase more than or equal to 2-fold. The combination of SPI feeding and E2 altered expression of 422 genes and reversed E2 effects on many mRNAs, including those involved in the c-myc signaling pathway, cyclin D1, and Ki67. ER? binding to its response element on the Tie-2/Tek and progesterone receptor promoters was increased by E2, but not SPI, and this promoter binding was suppressed by the combination of E2 + SPI for the Tie-2/Tek promoter but increased for the progesterone receptor promoter (P < 0.05). SPI reduced the ratio of epithelial to fat pad area and E2 + SPI reduced both epithelial and fat pad area (P < 0.05). These data suggest that SPI is only minimally estrogenic in the rat mammary gland even in the absence of endogenous estrogens. PMID:23027806

Ronis, Martin J J; Shankar, Kartik; Gomez-Acevedo, Horacio; Hennings, Leah; Singhal, Rohit; Blackburn, Michael L; Badger, Thomas M

2012-12-01

190

Cloning and Pharmacological Characterization of a Rat kappa Opioid Receptor  

Microsoft Academic Search

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%

Fan Meng; Guo-Xi Xie; Robert C. Thompson; Alfred Mansour; Avram Goldstein; Stanley J. Watson; Huda Akil

1993-01-01

191

Molecular and morphological characterization of local apple cultivars in Southern Spain.  

PubMed

The number of local and traditional fruit cultivars in Andalusia (Southern Spain) has decreased dramatically since the 1970s when new commercial cultivars from breeding programs were introduced, replacing old varieties, and thus decreasing genetic diversity. The present study was included in a genetic resources project with the objective of identifying and preserving traditional fruit tree cultivars in Southern Spain. The goal of this study was to begin the characterization of 29 apple accessions (Malus x domestica Borkh) belonging to 13 traditional cultivar denominations. For molecular characterization studies, 12 simple sequence repeat markers previously developed for apple species were used. Morphological characterization was performed using 33 fruit traits. A total of 115 alleles were amplified for the 12 loci, ranging from 7 (CH01h01, CH01h10, and GD 12) to 13 alleles per locus (CH02c11). Forty-one alleles were unique to specific genotypes. The locus with the highest number of detected unique alleles was CH01f03b with 6 alleles. Expected heterozygosity ranged from 0.74 for CH01h10 to 0.88 for CH02c11, with an average of 0.82. Observed heterozygosity varied from 0.45 for CH01h01 to 1.0 for CH02d08, with an average of 0.86. Three homonyms were found for accessions belonging to varieties 'Maguillo', 'Pero Minguela', and 'Castellana'. The most discriminant morphological characters studied revealed no homonyms or synonyms among cultivar denominations, although they are useful for describing varietal characteristics that have not been previously defined. PMID:25730088

Pérez-Romero, L F; Suárez, M P; Dapena, E; Rallo, P

2015-01-01

192

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...

193

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

194

Morphological and morphometric characterization of direct transdifferentiation of support cells into hair cells in ototoxin-exposed neonatal utricular explants.  

PubMed

We have studied aminoglycoside-induced vestibular hair-cell renewal using long-term culture of utricular macula explants from 4-day-old rats. Explanted utricles were exposed to 1 mM of gentamicin for 48 h, during 2nd and 3rd days in vitro (DIV), and then recovering in unsupplemented medium. Utricles were harvested at specified time points from the 2nd through the 28th DIV. The cellular events that occurred within hair cell epithelia during the culture period were documented from serial sectioned specimens. Vestibular hair cells (HCs) and supporting cells (SCs) were systematically counted using light microscopy (LM) with the assistance of morphometric software. Ultrastructural observations were made from selected specimens with transmission electron microscopy (TEM). After 7 DIV, i.e. four days after gentamicin exposure, the density of HCs was 11% of the number of HCs observed in non-gentamicin-exposed control explants. At 28 DIV the HC density was 61% of the number of HCs observed in the control group explant specimens. Simultaneously with this increase in HCs there was a corresponding decline in the number of SCs within the epithelium. The proportion of HCs in relation to SCs increased significantly in the gentamicin-exposed explant group during the 5th to the 28th DIV period of culture. There were no significant differences in the volume estimations of the gentamicin-exposed and the control group explants during the observed period of culture. Morphological observations showed that gentamicin exposure induced extensive loss of HCs within the epithelial layer, which retained their intact apical and basal linings. At 7 to 14 DIV (i.e. 3-11 days after gentamicin exposure) a pseudostratified epithelium with multiple layers of disorganized cells was observed. At 21 DIV new HCs were observed that also possessed features resembling SCs. After 28 DIV a new luminal layer of HCs with several layers of SCs located more basally characterized the gentamicin-exposed epithelium. No mitoses were observed within the epithelial layer of any explants. Our conclusion is that direct transdifferentiation of SCs into HCs was the only process contributing to the renewal of HCs after gentamicin exposure in these explants of vestibular inner ear epithelia obtained from the labyrinths of 4-day-old rats. PMID:25576788

Werner, Mimmi; Van De Water, Thomas R; Hammarsten, Peter; Arnoldsson, Göran; Berggren, Diana

2015-03-01

195

A comparison of the morphology of denervated with aneurally regenerated soleus muscle of rat  

Microsoft Academic Search

Soleus muscles of rats were denervated, treated with bupivacaine and autografted in order to induce aneural regeneration or only denervated. After 2–70 days, muscles were fixed and embedded in epoxy resin for light and electron microscopy. Regenerating muscles after 2 and 5 days consisted of a necrotic core and a rim of new fibres; the necrotic core had disappeared by

H. Schmalbruch; D. M. Lewis

1994-01-01

196

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...

197

MORPHOLOGIC ANALYSIS CORRELATES WITH GENE EXPRESSION CHANGES IN CULTURED F344 RAT MESOTHELIAL CELLS  

EPA Science Inventory

The gene expression pattern of mesothelial cells in vitro was determined after 4 or 12 h exposure to the rat mesothelial, kidney and thyroid carcinogen, and oxidative stressor potassium bromate (KBr03). Gene expression changes observed using cDNA arrays indicated oxidative stres...

198

Cosmos 1887: morphology, histochemistry, and vasculature of the growing rat tibia.  

PubMed

Light microscopy, electron microscopy, and enzyme histochemistry were used to study the effects of spaceflight on metaphyseal and cortical bone of the rat tibia. Cortical cross-sectional area and perimeter were not altered by a 12.5-day spaceflight in 3-month-old male rats. The endosteal osteoblast population and the vasculature near the periosteal surface in flight rats compared with ground controls showed more pronounced changes in cortical bone than in metaphyseal bone. The osteoblasts demonstrated greater numbers of transitional Golgi vesicles, possibly caused by a decreased cellular metabolic energy source, but no difference in the large Golgi saccules or the cell membrane-associated alkaline phosphatase activity. The periosteal vasculature in the diaphysis of flight rats often showed lipid accumulations within the lumen of the vessels, occasional degeneration of the vascular wall, and degeneration of osteocytes adjacent to vessels containing intraluminal deposits. These changes were not found in the metaphyseal region of flight animals. The focal vascular changes may be due to ischemia of bone or a developing fragility of the vessel walls as a result of spaceflight. PMID:2153083

Doty, S B; Morey-Holton, E R; Durnova, G N; Kaplansky, A S

1990-01-01

199

Cosmos 1887: morphology, histochemistry, and vasculature of the growing rat tibia  

NASA Technical Reports Server (NTRS)

Light microscopy, electron microscopy, and enzyme histochemistry were used to study the effects of spaceflight on metaphyseal and cortical bone of the rat tibia. Cortical cross-sectional area and perimeter were not altered by a 12.5-day spaceflight in 3-month-old male rats. The endosteal osteoblast population and the vasculature near the periosteal surface in flight rats compared with ground controls showed more pronounced changes in cortical bone than in metaphyseal bone. The osteoblasts demonstrated greater numbers of transitional Golgi vesicles, possibly caused by a decreased cellular metabolic energy source, but no difference in the large Golgi saccules or the cell membrane-associated alkaline phosphatase activity. The periosteal vasculature in the diaphysis of flight rats often showed lipid accumulations within the lumen of the vessels, occasional degeneration of the vascular wall, and degeneration of osteocytes adjacent to vessels containing intraluminal deposits. These changes were not found in the metaphyseal region of flight animals. The focal vascular changes may be due to ischemia of bone or a developing fragility of the vessel walls as a result of spaceflight.

Doty, S. B.; Morey-Holton, E. R.; Durnova, G. N.; Kaplansky, A. S.

1990-01-01

200

The morphological and chemical characteristics of striatal neurons immunoreactive for the alpha1-subunit of the GABA(A) receptor in the rat.  

PubMed

The distribution, morphology and chemical characteristics of neurons immunoreactive for the alpha1-subunit of the GABA(A) receptor in the striatum of the basal ganglia in the rat brain were investigated at the light, confocal and electron microscope levels using single, double and triple immunohistochemical labelling techniques. The results showed that alpha1-subunit immunoreactive neurons were sparsely distributed throughout the rat striatum. Double and triple labelling results showed that all the alpha1-subunit-immunoreactive neurons were positive for glutamate decarboxylase and immunoreactive for the beta2,3 and gamma2 subunits of the GABA(A) receptor. Three types of alpha1-subunit-immunoreactive neurons were identified in the striatum on the basis of cellular morphology and chemical characteristics. The most numerous alpha1-subunit-immunoreactive neurons were medium-sized, aspiny neurons with a widely branching dendritic tree. They were parvalbumin-negative and were located mainly in the dorsolateral regions of the striatum. Electron microscopy showed that these neurons had an indented nuclear membrane, typical of striatal interneurons, and were surrounded by small numbers of axon terminals which established alpha1-subunit-immunoreactive synaptic contacts with the soma and dendrites. These cells were classified as type 1 alpha1-subunit-immunoreactive neurons and comprised 75% of the total population of alpha1-subunit-immunoreactive neurons in the striatum. The remaining alpha1-subunit-immunoreactive neurons comprised of a heterogeneous population of large-sized neurons localized in the ventral and medial regions of the striatum. The most numerous large-sized cells were parvalbumin-negative, had two to three relatively short branching dendrites and were designated type 2 alpha1-subunit-immunoreactive neurons. Electron microscopy showed that the type 2 neurons were characterized by a highly convoluted nuclear membrane and were sparsely covered with small axon terminals. The type 2 neurons comprised 20% of the total population of alpha1-subunit-immunoreactive neurons. The remaining large-sized alpha1-immunoreactive cells were designated type 3 cells; they were positive for parvalbumin and were distinguished by long branching dendrites extending dorsally for 600-800 microm into the striatum. These neurons comprised 5% of the total population of alpha1-subunit-immunoreactive neurons and were surrounded by enkephalin-immunoreactive terminals. Electron microscopy showed that the alpha1-subunit type 3 neurons had an indented nuclear membrane and were densely covered with small axon terminals which established alpha1-subunit-immunoreactive symmetrical synaptic contacts with the soma and dendrites. These results provide a detailed characterization of the distribution, morphology and chemical characteristics of the alpha1-subunit-immunoreactive neurons in the rat striatum and suggest that the type 1 and type 2 neurons comprise of separate populations of striatal interneurons while the type 3 neurons may represent the large striatonigral projection neurons described by Bolam et al. [Bolam J. P., Somogyi P., Totterdell S. and Smith A. D. (1981) Neuroscience 6, 2141-2157.]. PMID:9276493

Waldvogel, H J; Kubota, Y; Trevallyan, S C; Kawaguchi, Y; Fritschy, J M; Mohler, H; Faull, R L

1997-10-01

201

Preservation of photoreceptor morphology and function in P23H rats using an allele independent ribozyme.  

PubMed

To develop an allele independent ribozyme for the treatment of autosomal dominant retinitis pigmentosa (ADRP) associated with mutations in the rhodopsin (RHO) gene, a ribozyme targeting dog, mouse, human but not rat rhodopsin (RHO) mRNA was designed and tested in vitro. Activity of this ribozyme was tested in tissue culture by co-transfection of HEK 293 cells with plasmids expressing opsin mRNA and ribozyme, followed by quantitative RT-PCR to evaluate the level of RHO mRNA. For experiments in vivo, Rz525 driven by the mouse opsin proximal promoter was inserted in plasmids with AAV 2 terminal repeats (TR) and packaged in AAV serotype 5 capsids. AAV-Rz525 was injected subretinally into the right eyes of P23H rat pups. Left eyes were injected with virus expressing GFP from the identical promoter. Animals were analyzed at 4, 8 and 12 weeks post-injection by full field scotopic electroretinography (ERG). After 12 weeks, animals were sacrificed and retinas were dissected, fixed and sectioned. Rz525 had high catalytic activity in vitro and led to a 50% reduction of RHO mRNA in cells. AAV-Rz525 injection into P23H transgenic rats led to significant preservation (about 50%) of scotopic ERG a- and b-wave amplitudes. Histological analysis showed an increased number of ONL nuclei in the central and superior retina of treated eyes relative to control eyes. RT-PCR analysis revealed 46% reduction of transgenic (mouse) RHO mRNA in right eyes relative to left eyes and no change in rat RHO mRNA. AAV5 delivery of Rz525 resulted in a partial rescue of the light response and structural preservation of photoreceptors in transgenic rats. This ribozyme may be a useful component of an RNA replacement gene therapy for ADRP. PMID:17083931

Gorbatyuk, M; Justilien, V; Liu, J; Hauswirth, W W; Lewin, A S

2007-01-01

202

Morphological and neurohistological changes in adolescent rats administered with nicotine during intrauterine life.  

PubMed

Tobacco smoking has been linked to many preventable diseases affecting various organs and systems of the body, including the brain. The current study was conducted to demonstrate the histological changes observable in the cerebral cortex of young Wistar rats exposed to nicotine during gestation. Vaginal smearing was conducted for the female Wistar rats to determine their oestrous cycle, after which they were exposed to male rats overnight, for mating. Pregnancy was confirmed and the pregnant rats were divided into 3 groups based on the 3 trimesters (A, B, C), with each group having a control and a treated subgroup. The Control Groups (A1, B1, C1) were given 0.1 ml of normal saline i. p., while the Treated Groups (A2, B2, C2) received 0.06 mg/kg/0.1 ml of nicotine intra-peritoneally. Treatment was for a period of 6 days only within each trimester for all subgroups. The pregnant animals were allowed to litter, and at postnatal day 35 they were sacrificed. The skull was dissected to expose and remove the brain; the temporal and parietal cortices were excised and fixed in 4% paraformaldehyde for histological tissue preparation, using cresyl fast violet staining techniques. Exposure of the developing brain to nicotine during gestation resulted in various degrees of abnormalities in the cytoarchitecture of the parietal and temporal cortices of young rats. The gestational period of nicotine exposure and specific cortical affectation are important factors to consider while investigating neurological abnormalities in offspring of tobacco smokers. PMID:24937389

Omotoso, G O; Ibitolu, J O; Femi-Akinlosotu, O M; Akinola, O B; Enaibe, B U

2013-01-01

203

Progesterone and its derivatives dihydroprogesterone and tetrahydroprogesterone reduce myelin fiber morphological abnormalities and myelin fiber loss in the sciatic nerve of aged rats  

Microsoft Academic Search

Previous studies indicate that steroid hormones may be protective for Schwann cells and promote the expression of myelin proteins in the sciatic nerve of adult rats. In this study, we have evaluated the effect of progesterone (P), dihydroprogesterone (DHP), tetrahydroprogesterone (THP), testosterone (T), dihydrotestosterone (DHT) and 5?-androstan-3?, 17?-diol (3?-diol) on the morphological alterations of myelinated fibers in the sciatic nerve

Iñigo Azcoitia; Emanuela Leonelli; Valerio Magnaghi; Sergio Veiga; Luis M Garcia-Segura; Roberto C Melcangi

2003-01-01

204

Morphological and electromechanical characterization of ionic liquid/Nafion polymer composites  

NASA Astrophysics Data System (ADS)

Ionic liquids have shown promise as replacements for water in ionic polymer transducers. Ionic liquids are non-volatile and have a larger electrochemical stability window than water. Therefore, transducers employing ionic liquids can be operated for long periods of time in air and can be actuated with higher voltages. Furthermore, transducers based on ionic liquids do not exhibit the characteristic back relaxation that is common with water-swollen materials. However, the physics of transduction in the ionic liquid-swollen materials is not well understood. In this paper, the morphology of Nafion/ionic liquid composites is characterized using small-angle X-ray scattering (SAXS). The electromechanical transduction behavior of the composites is also investigated. For this testing, five different counterions and two ionic liquids are used. The results reveal that both the morphology and transduction performance of the composites is affected by the identity of the ionic liquid, the cation, and the swelling level of ionic liquid within the membrane. Specifically, speed of response is found to be lower for the membranes that were exchanged with the smaller lithium and potassium ions. The response speed is also found to increase with increased content of ionic liquid. Furthermore, for the two ionic liquids studied, the actuators swollen with the less viscous ionic liquid exhibited a slower response. The slower speed of response corresponds to less contrast between the ionically conductive phase and the inert phase of the polymer. This suggests that disruption of the clustered morphology in the ionic liquid-swollen membranes as compared to water-swollen membranes attenuates ion mobility within the polymer. This attenuation is attributed to swelling of the non-conductive phase by the ionic liquids.

Bennett, Matthew; Leo, Donald

2005-05-01

205

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

206

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

207

Long-term characterization of persistent atrial fibrillation: wave morphology, frequency, and irregularity analysis.  

PubMed

Short-term properties of atrial fibrillation (AF) frequency, f-wave morphology, and irregularity parameters have been thoroughly studied, but not long-term properties. In the present work, f-wave morphology is characterized by principal component analysis, introducing a novel temporal parameter defined by the cumulative normalized variance of the three largest principal components (r3). Based on 7-day recordings from nine patients with stable chronic heart failure and persistent AF, long-term properties were studied in terms of r3 AF frequency, and sample entropy (SampEn). The main result of the present study is that detection of circadian rhythms depends on the parameter considered: rhythms were found in six (r3, SampEn) and five (AF frequency) patients, but not always in the same patient. Another important result is that circadian rhythms detected in 7-day recordings could not always be detected in 24-h periods, thus shedding new light on the results in previous studies which all were based on 24-h recordings. Infradian rhythms were found in four (r3, SampEn) and one (AF frequency) patients. PMID:25284217

Goya-Esteban, Rebeca; Sandberg, Frida; Barquero-Pérez, Óscar; García-Alberola, Arcadio; Sörnmo, Leif; Rojo-Álvarez, José Luis

2014-12-01

208

Morphological and cytoenzymatic characterization of haemocytes of the venus clam Chamelea gallina.  

PubMed

A morphological and enzymatic characterization of Chamelea gallina haemocytes was carried out as a prerequisite for further studies on venus clam immunobiology. Two main types of circulating haemocytes were identified (1) hyalinocytes (79.2%), agranular cells with a central nucleus surrounded by a little cytoplasm, and (2) granulocytes (16.5%), smaller granular cells with smaller nuclei. Small cells with a strongly basophilic nucleus and a thin layer of peripheral cytoplasm, probably undifferentiated blast cells (4.3%), were also observed. Both granulocytes and hyalinocytes can assume a spreading or round morphology. The enzymatic activities of haemocytes were also investigated. Some of the granulocytes and hyalinocytes were positive for hydrolytic enzymes, suggesting a role for these cells in phagocytosis; no oxidative enzymes were detected in C. gallina haemocytes. Granulocytes and hyalinocytes can easily adhere to the substratum and exhibit a low phagocytosis activity towards foreign particles (6.3%), whereas the fraction of cells containing ingested material significantly increased after pre-incubation of test particles with cell-free haemolymph, which suggests the presence of opsonin(s) in the haemolymph. PMID:12113309

Pampanin, Daniela M; Marin, M Gabriella; Ballarin, Loriano

2002-06-01

209

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

210

Morphological investigation and physical characterization of ancient fragments of pyrogenic carbon  

NASA Astrophysics Data System (ADS)

In the latest years, the attention toward the use of pyrogenic carbon as a climate mitigation strategy has increasingly grown. Biochar (BC) contains substantial amount (60-90%) of pyrogenic carbon, which is a recalcitrant material and it is hardly decomposed by biotic and abiotic oxidation. The carbon mitigation potential of biochar is associated to the fact that carbon is not easily released back into the atmosphere, even after very long incubation time in the soil. Several studies have been addressing the understanding of the fate of pyrogenic carbon in the soil in a quantitative way, but only a few actually considered materials that were produced in the past and they were not fully able to estimate the fraction of carbon that was oxidized on centennial time scales. In this paper, an old deposits of biochar in soils of the Eastern Alps (Trentino, Val di Pejo) was dated at 1859 by means of a dendroanthracological approach. Carbon decomposition in those soils was then investigated to calculate the fraction of carbon that was lost over 155 years. Part of this study is focused on the morphological and physical characterization of several fragments of biochar, using a scanning electron microscope (SEM). Such study enabled the identification of specific morphological features of tracheids in the old biochar, which were tentatively associated to a differential oxidation of the structures that were created during carbonization from lignin and cellulose.

Pusceddu, E.; Criscuoli, I.; Miglietta, F.

2013-12-01

211

Clinical, Morphological, and Molecular Characterization of Penicillium canis sp. nov., Isolated from a Dog with Osteomyelitis  

PubMed Central

Infections caused by Penicillium species are rare in dogs, and the prognosis in these cases is poor. An unknown species of Penicillium was isolated from a bone lesion in a young dog with osteomyelitis of the right ilium. Extensive diagnostic evaluation did not reveal evidence of dissemination. Resolution of lameness and clinical stability of disease were achieved with intravenous phospholipid-complexed amphotericin B initially, followed by long-term combination therapy with terbinafine and ketoconazole. A detailed morphological and molecular characterization of the mold was undertaken. Sequence analysis of the internal transcribed spacer revealed the isolate to be closely related to Penicillium menonorum and Penicillium pimiteouiense. Additional sequence analysis of ?-tubulin, calmodulin, minichromosome maintenance factor, DNA-dependent RNA polymerase, and pre-rRNA processing protein revealed the isolate to be a novel species; the name Penicillium canis sp. nov. is proposed. Morphologically, smooth, ovoid conidia, a greenish gray colony color, slow growth on all media, and a failure to form ascomata distinguish this species from closely related Penicillium species. PMID:24789186

Sutton, Deanna A.; Swenson, Cheryl L.; Bailey, Chris J.; Wiederhold, Nathan P.; Nelson, Nathan C.; Thompson, Elizabeth H.; Wickes, Brian L.; French, Stephanie; Fu, Jianmin; Vilar-Saavedra, Paulo

2014-01-01

212

Morphological Characterization of Elastin-Mimetic Block Copolymers Utilizing Cryo- and Cryoetch-HRSEM  

NASA Astrophysics Data System (ADS)

Elastin-mimetic block copolymers were produced by genetic engineering. Genetically driven synthesis permitted control of the final physiochemical characteristics of the block copolymers. We designed BB and BAB block copolymers in which the A-block was hydrophilic and the B-block was hydrophobic. By designing the copolymers in this manner, it was proposed that they would self-assemble into micellar aggregates that, at high concentration, would form thermoreversible hydrogels. To analyze the three-dimensional fine surface morphology of the copolymers, to the resolution level of a few nanometers, we employed cryo-HRSEM. This method provided vast expanses of the specimen in its frozen hydrated state for survey. In our initial cryo-HRSEM studies, we observed the protein filaments and micelles surrounded by lakes of vitreous ice. Upon examination at low and intermediate magnifications, there was an extensive honeycomb-like filamentous network. To delineate the fine morphology of the hydrogel network at high magnification and to greater depths, we cryoetched away unbound water from the sample surface, in high vacuum, prior to chromium deposition. By using this technique, we were able to visualize for characterization purposes the fine fibril networks formed from the micellar aggregates over the surface of the hydrogel.

Wright, Elizabeth R.; Conticello, Vincent P.; Apkarian, Robert P.

2003-06-01

213

Morphology, Structure and Function Characterization of PEI Modified Magnetic Nanoparticles Gene Delivery System  

PubMed Central

Modified magnetic nanoparticles are used as non-viral gene carriers in biological applications. To achieve successful gene delivery, it is critical that nanoparticles effectually assemble with nucleic acids. However, relatively little work has been conducted on the assemble mechanisms between nanoparticles and DNA, and its effects on transfection efficiency. Using biophysical and biochemical characterization, along with Atomic force microscopy (AFM) and Transmission electron microscopy (TEM), we investigate the morphologies, assembling structures and gene delivering abilities of the PEI modified magnetic nanoparticles (MNPs) gene delivery system. In this gene delivery system, MNP/DNA complexes are formed via binding of DNA onto the surface of MNPs. MNPs are favorable to not only increase DNA concentration but also prevent DNA degradation. Magnetofection experiments showed that MNPs has low cytotoxicity and introduces highly stable transfection in mammalian somatic cells. In addition, different binding ratios between MNPs and DNA result in various morphologies of MNP/DNA complexes and have an influence on transfection efficiency. Dose–response profile indicated that transfection efficiency positively correlate with MNP/DNA ratio. Furthermore, intracellular tracking demonstrate that MNPs move though the cell membranes, deliver and release exogenous DNA into the nucleus. PMID:24911360

Zhao, Xiang; Cui, Haixin; Chen, Wenjie; Wang, Yan; Cui, Bo; Sun, Changjiao; Meng, Zhigang; Liu, Guoqiang

2014-01-01

214

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

215

Morphological and molecular characterization of renal ciliates infecting farmed snails in Spain.  

PubMed

Renal infections by parasitic ciliates were studied in adult snails of Helix aspersa aspersa and Helix aspersa maxima collected from 2 mixed rearing system-based heliciculture farms located in Galicia (NW Spain). The occurrence of ciliates was also examined in slugs (Deroceras reticulatum) invading the greenhouses where first growing and fattening of snails is carried out. Histological examinations revealed a severe destruction of the renal epithelium in heavily infected hosts. Three ciliate isolates, one from each host species, were obtained and grown in axenic cultures. Cultured and parasitic ciliates were characterized morphologically and morphometrically. In addition, the encystment behaviour, the occurrence of autogamy, and the sequences of the mitochondrial cytochrome-c oxidase subunit 1 (cox1) and the small subunit ribosomal RNA (SSU rRNA) genes were also studied in the 3 isolates. A polymorphic life cycle involving resting and reproductive cysts, together with the morphological and morphometrical characteristics and the confirmation that autogamy occurs within cysts, demonstrate that our ciliates belong to the species Tetrahymena rostrata (Kahl, 1926) Corliss, 1952. The 3 isolates formed a well-supported clade using both genetic markers, and were clearly separate from the strain ATCC(R) 30770, which has been identified as Tetrahymena rostrata. We argue that our Spanish isolates should be regarded as Tetrahymena rostrata, and that the ATCC isolate should be regarded as a misidentification as neither cytological nor cytogenetical support for its identity has been presented. PMID:19402940

Segade, P; Kher, C P; Lynn, D H; Iglesias, R

2009-06-01

216

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

217

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

218

Spectroscopic and morphological characterization of inflow cannulas of left ventricular assist devices.  

PubMed

Despite the consistent clinical data on the positive effects of left ventricular assist devices (LVADs) in the treatment of refractory heart failure, unfortunately these devices yet show some limitations such as the risk of stroke, infection, and device malfunction. The complex interplay between blood and the foreign material has a major role in the occurrence of these complications and biocompatibility of the inflow cannula would be pivotal in these terms. In this study, we carried out an in-depth physicochemical characterization of two commercially available LVADs by means of field emission gun scanning electron microscopy, energy dispersive X-ray, and X-ray photoelectron spectra. Our results show that, despite both pumps share the same physicochemical concepts, major differences can be identified in the surface nature, morphology, and chemical composition of their inflow cannulas. PMID:25396275

Pappalardo, Federico; Cristaldi, Domenico A; Fragalà, Ignazio L; Millesi, Salvatrice; De Bonis, Michele; Gulino, Antonino

2015-01-01

219

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

220

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

2015-03-01

221

Chronic morphine exposure alters the dendritic morphology of pyramidal neurons in visual cortex of rats  

Microsoft Academic Search

Repeated treatment of psychotropic drugs produces changes in brain and behavior that far outlast their initial neuropharmacological effects. The nature of persistent drug-induced neural plasticity is of interest because it is thought to contribute to the development of drug dependency and addiction. To determine if chronic morphine treatment alters the morphology of visual cortical neurons, we statistically examined the dendrites

Yanfei Li; Hao Wang; Lei Niu; Yifeng Zhou

2007-01-01

222

Rat prostatic growth factors: purification and characterization of high and low molecular weight epidermal growth factors from rat dorsolateral prostate.  

PubMed

Growth factors which possibly participate in androgen-induced proliferation of rat prostate epithelial cells have been purified and characterized. Four distinct forms of growth factor were found in the extract of rat dorsolateral prostate. One of the factors was a member of heparin-binding growth factor (HBGF) family judging from its high affinity for heparin-Sepharose. The other three factors were capable of competing with [125I]epidermal growth factor (EGF) for the cell surface receptor, and recognized by anti-rat EGF antiserum. These EGF-like factors (EGF1-EGF3) were purified by ion-exchange chromatography, gel filtration and reverse phase HPLC. EGF1 showed microheterogeneity on chromatographic and electrophoretic separation and N-terminal sequence analysis. EGF1 showed an average molecular weight of about 35,000 on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions. These results indicated that EGF1 was a mixture of high molecular weight forms of EGF. The molecular weights of EGF2 and EGF3 were similar to that of rat submaxillary gland EGF (Mr = 5400). The amino acid sequence of EGF2 was identical with that of rat EGF except for the N- and C-terminal amino acids: aspartic acid instead of asparagine was found at the N-terminal position and C-terminal arginine was missing in EGF2. Although the N-terminal sequence of EGF3 (1-19) was identical with that of EGF2, the two factors were completely separated by gel filtration indicating a difference in the C-terminal structure. EGF1, EGF2 and EGF3 but not HBGF stimulated proliferation of primary cultured rat dorsolateral prostate epithelial cells. PMID:1958699

Nishi, N; Shimizu, C; Okutani, T; Kagawa, Y; Takasuga, H; Suno, M; Wada, F

1991-11-12

223

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; Åberg, Elin

2015-01-01

224

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

225

Memantine reduces functional and morphological consequences induced by global ischemia in rats  

Microsoft Academic Search

In this study the effect of memantine, an antagonist at the N-methyl-d-aspartate receptor, on spatial learning deficit and on neuronal damage following transient: cerebral ischemia was evaluated. Global ischemia was induced by four-vessel-occlusion (4VO) for 20 min in rats. Memantine was administered 20 min before induction of ischemia at a dose of 10 or 20 mg\\/kg. One week after surgery

F. Block; M. Schwarz

1996-01-01

226

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. PMID:25653795

Soleimanzadeh, Ali; Saberivand, Adel

2013-01-01

227

Prediction of neural differentiation fate of rat mesenchymal stem cells by quantitative morphological analyses using image processing techniques.  

PubMed

Abstract Differentiation of bone marrow mesenchymal stem cells (BMSCs) into neural cells has received significant attention in recent years. However, there is still no practical method to evaluate differentiation process non-invasively and practically. The cellular quality evaluation method is still limited to conventional techniques, which are based on extracting genes or proteins from the cells. These techniques are invasive, costly, time consuming, and should be performed by relevant experts in equipped laboratories. Moreover, they cannot anticipate the future status of cells. Recently, cell morphology has been introduced as a feasible way of monitoring cell behavior because of its relationship with cell proliferation, functions and differentiation. In this study, rat BMSCs were induced to differentiate into neurons. Subsequently, phase contrast images of cells taken at certain intervals were subjected to a series of image processing steps and cell morphology features were calculated. In order to validate the viability of applying image-based approaches for estimating the quality of differentiation process, neural-specific markers were measured experimentally throughout the induction. The strong correlation between quantitative imaging metrics and experimental outcomes revealed the capability of the proposed approach as an auxiliary method of assessing cell behavior during differentiation. PMID:25324434

Kazemimoghadam, Mahdieh; Janmaleki, Mohsen; Fouani, Mohamad Hassan; Abbasi, Sara

2015-02-01

228

A LIGHT AND ELECTRON MICROSCOPE STUDY OF THE MORPHOLOGICAL CHANGES INDUCED IN RAT LIVER CELLS BY THE AZO DYE 2-ME-DAB  

PubMed Central

The cytological changes induced in rat liver cells by the aminoazo dye 2-Me-DAB have been examined by light and electron microscopy. It is observed that this non-carcinogenic compound duplicates most of the morphological alterations produced by other hepatotoxins, some of which, such as the closely related aminoazo dye 3'-Me-DAB, are potent carcinogens. These non-specific effects involve both the granular and agranular forms of the endoplasmic reticulum as well as the glycogen content of hepatic cells. The arrays of cisternal profiles of the granular reticulum in normal hepatic cells become disorganized and the dispersed cisternae often appear fragmented and irregular. Large cytoplasmic inclusions, consisting of loosely organized tubules and vesicles, are also observed which result from a hypertrophy of the agranular reticulum. The glycogen in the cells progressively decreases in amount. The most specific effect of 2-Me-DAB is to induce an increase in the number of mitochondria per cell. Many of these organelles are characterized by the presence of a median double membrane continuous with the inner limiting membrane of the mitochondrial envelope. Evidence is presented in favor of the view that this partition is directly related to the phenomenon of mitochondrial division. It was noted also in the course of the experiment that an increasing number of cells appear which stain quite intensely with methylene blue and appear denser than normal under electron microscopy. The significance of these cells is not known. PMID:14195607

Lafontaine, J. G.; Allard, C.

1964-01-01

229

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

230

Optimization and pharmacological characterization of a refined cisplatin-induced rat model of peripheral neuropathic pain.  

PubMed

Chemotherapy-induced peripheral neuropathy (CIPN) is the major dose-limiting side-effect of many front-line anticancer drugs. This study was designed to establish and pharmacologically characterize a refined rat model of cisplatin-induced CIPN. Adult male Sprague-Dawley rats received four (n=18) or five (n=18) single intraperitoneal bolus doses of cisplatin at 3?mg/kg, or saline (control group), once-weekly. Body weight and general health were assessed over a 49-day study period. von Frey filaments and the Hargreaves test were used to define the time course for the development of mechanical allodynia and thermal hypoalgesia in the hindpaws and for efficacy assessment of analgesic/adjuvant agents. The general health of rats administered four cisplatin doses was superior to that of rats administered five doses. Mechanical allodynia was fully developed (paw withdrawal thresholds?6?g) in the bilateral hindpaws from day 32 to 49 for both cisplatin dosing regimens. They also showed significant thermal hypoalgesia in the bilateral hindpaws. In cisplatin-treated rats with paw withdrawal thresholds of up to 6?g, single bolus doses of gabapentin and morphine produced dose-dependent analgesia, whereas meloxicam and amitriptyline lacked efficacy. We have established and pharmacologically characterized a refined rat model of CIPN that is suitable for efficacy profiling of compounds from analgesic discovery programmes. PMID:25325291

Han, Felicity Yaqin; Wyse, Bruce D; Smith, Maree T

2014-12-01

231

Genomic Organization, Tissue Distribution and Functional Characterization of the Rat Pate Gene Cluster  

PubMed Central

The cysteine rich prostate and testis expressed (Pate) proteins identified till date are thought to resemble the three fingered protein/urokinase-type plasminogen activator receptor proteins. In this study, for the first time, we report the identification, cloning and characterization of rat Pate gene cluster and also determine the expression pattern. The rat Pate genes are clustered on chromosome 8 and their predicted proteins retained the ten cysteine signature characteristic to TFP/Ly-6 protein family. PATE and PATE-F three dimensional protein structure was found to be similar to that of the toxin bucandin. Though Pate gene expression is thought to be prostate and testis specific, we observed that rat Pate genes are also expressed in seminal vesicle and epididymis and in tissues beyond the male reproductive tract. In the developing rats (20–60 day old), expression of Pate genes seem to be androgen dependent in the epididymis and testis. In the adult rat, androgen ablation resulted in down regulation of the majority of Pate genes in the epididymides. PATE and PATE-F proteins were found to be expressed abundantly in the male reproductive tract of rats and on the sperm. Recombinant PATE protein exhibited potent antibacterial activity, whereas PATE-F did not exhibit any antibacterial activity. Pate expression was induced in the epididymides when challenged with LPS. Based on our results, we conclude that rat PATE proteins may contribute to the reproductive and defense functions. PMID:22479333

Rajesh, Angireddy; Yenugu, Suresh

2012-01-01

232

Characterization of Mode I Fracture and Morphological Properties of PLLA Blends with Addition of Lysine Triisocyanate  

NASA Astrophysics Data System (ADS)

Poly(L-lactic acid) (PLLA) was toughened by blending with three different ductile biopolymers such as poly (?-caprolactone) (PCL), poly(butylene succinate-co-e-caprolactone) (PBSC), poly (butylene succinate-co-L-lactate) (PBSL). The blend ratio was fixed to 50:50. Lysine triisocyanate (LTI) was added to the blends as a compatibilizer. Characterizations such as Fourier transform infra-red (FT-IR) spectroscopy, field-emission electron microscope (FE-SEM), and mode I fracture test were used to characterize the effectiveness of LTI on the mechanical and morphological properties of various PLLA blends. It was found that PLLA/PCL blend shows the highest toughness energy among the binary blends. On the other hand, addition of LTI in PLLA/PBSC blend exhibits the best toughness property. Based on the FE-SEM observation, fractured surfaces of PLLA blends with LTI indicate ductile fracture with dense elongated fibrils. The largest damage zone is generated in the vicinity of crack-trip, suggesting that high energy dissipation occurred in the crack-trip region. FT-IR analysis also suggested that the NCO groups of LTI were acted as a compatibilizer, as the results of interaction between the two phases of the polymer blends.

Vannaladsaysy, Vilay; Todo, Mitsugu

233

Improved islet morphology after blockade of the renin- angiotensin system in the ZDF rat.  

PubMed

The renin-angiotensin system (RAS) has an important role in the endocrine pancreas. Although angiotensin II has significant effects on cell proliferation and apoptosis, the contribution of the RAS to changes in islet structure and function associated with type 2 diabetes is yet to be defined. This study examined the specific effects of RAS blockade on islet structure and function in diabetes. Thirty-six male Zucker diabetic fatty (ZDF) rats, 10 weeks of age, were randomized to receive the angiotensin-converting enzyme inhibitor perindopril (8 mg/l in drinking water; n = 12), irbesartan (15 mg/kg via gavage; n = 12), or no treatment (n = 12) for 10 weeks. Results were compared with lean littermates (ZL) (n = 12) studied concurrently. ZDF rats had increased intra-islet expression of components of the RAS correlating with increased intraislet fibrosis, apoptosis, and oxidative stress. Disordered islet architecture, seen in ZDF rats, was attenuated after treatment with perindopril or irbesartan. Islet fibrogenesis was also diminished, as measured by picrosirius staining and expression of collagens I and IV. Gene expression of transforming growth factor-beta1 was increased in the ZDF pancreas (ZL, 1.0 +/- 0.1; ZDF, 2.0 +/- 0.3; P < 0.05) and reduced after blockade of the RAS (ZDF + P, 1.3 +/- 0.2; ZDF + I, 1.5 +/- 0.1; vs. ZDF, both P < 0.05). Improvements in structural parameters were also associated with functional improvements in first-phase insulin secretion. These findings provide a possible mechanism for the reduced incidence of new-onset diabetes that has been observed in clinical trials of RAS blockade. PMID:15047614

Tikellis, Christos; Wookey, Peter J; Candido, Riccardo; Andrikopoulos, Sof; Thomas, Merlin C; Cooper, Mark E

2004-04-01

234

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

E-print Network

composition: control (corn oil), diets 1, 2, and 3 [test oil $1 (58. 58 18:2 and 0. 78 18:3 fatty acids), oil $2 (46. 4% 18:2 and 3. 68 18:3 fatty acids), and oil g 3 (55. 7% 18:2 and 18:3 fatty acids), respectively], and diet 4 which was fat...-free. The diets were initiated when the rats were 4 wk old. Body weight (p&0. 001), fat pad weight (p&0. 001), and adipocyte diameter (p&0. 05) were significantly less in the exercised group than in the sedentary group. Adipocyte number was not significantly...

Neale, Sonia Barstad

1989-01-01

235

The Immunoexpression of FSH-R in the Ductuli Efferentes and the Epididymis of Men and Rat: Effect of FSH on the Morphology and Steroidogenic Activity of Rat Epididymal Epithelial Cells In Vitro  

PubMed Central

The Sertoli cells were regarded as the only target for FSH in male reproductive system. The expression of FSH receptor (FSH-R) was detected also in epithelial cells of the caput epididymis of rat and monkey. We showed in the immunohistochemistry study the expression of FSH-R in rat and human ductuli efferentes and the caput, corpus, and cauda epididymis, moreover, by Western blot analysis in the caput and cauda epididymis of rat. Additionally, we presented that the morphology of rat epididymal epithelial cells in vitro was affected by FSH, and FSH stimulation resulted in the increase of 17?-estradiol synthesis by rat caput epididymal cells in dose-depended manner. In conclusion, the identification of FSH receptors in human and rat epididymides supports our results that the epididymis is a target organ not only for LH but additionally for FSH. On the basis of the results we showed for the first time that morphology of epididymal epithelial cells and epididymal steroidogenesis can be regulated by FSH. PMID:20467586

?wider-Al-Amawi, Ma?gorzata; Kolasa, Agnieszka; Sikorski, Andrzej; Marchlewicz, Mariola; Baranowska-Bosiacka, Irena; Wiszniewska, Barbara

2010-01-01

236

Characterization of a rat model of right-sided heart failure induced by pulmonary trunk banding  

Microsoft Academic Search

Animal models of disease are essential for cardiovascular research. However, animal models of right-sided heart failure are few and remain poorly characterized. The aim with this study was to establish a rat model of right-sided heart failure (HF) using pulmonary trunk banding (PTB) and subsequently to characterize the systemic and cardiac changes in this model, including protein expression of SERCA2

Uffe K. Schou; Christian D. Peters; Soo Wan Kim; Jørgen Frøkiær; Søren Nielsen

2007-01-01

237

Utopia Basin, Mars: Characterization of topography and morphology and assessment of the origin and evolution of basin internal structure  

E-print Network

Utopia Basin, Mars: Characterization of topography and morphology and assessment of the origin of Utopia Planitia. The new topographic data convincingly demonstrate that the Utopia region is an impact deep depression $3200 km in diameter. Utopia Basin is the largest easily recognizable impact structure

Head III, James William

238

Characterization of fungi from hypersaline environments of solar salterns using morphological and molecular techniques.  

PubMed

The Cabo Rojo Solar Salterns located on the southwest coast of Puerto Rico are composed of two main ecosystems (i.e., salt ponds and microbial mats). Even though these locations are characterized by high solar radiation (mean light intensity of 39 mol photons m-2d-1) they harbour a diverse microscopic life. We used morphological and molecular techniques to identify a series of halotolerant fungi. A total of 183 isolates and 36 species were cultured in this study. From the water from the salt ponds, 86 isolates of 26 species were cultured. The halotolerant fungi isolated from water were: Cladosporium cladosporioides, nine Aspergillus sp., five Penicillium sp. and the black yeast Hortaea werneckii. A distinctive isolate with a blue mycelium was cultured from the salt ponds, representing a new species of Periconia based on morphology and rDNA analysis. Forty-four isolates from eight species were cultured from the sediments around the salt ponds. Most of the sediment isolates formed only sterile mycelium, while several were Chaetomium globosum. A total of 53 isolates from 16 species were isolated from the three layers of the microbial mats, of which Aspergillus niger was the most frequent isolate. Phospholipid fatty acid profiles generated from the different layers of the microbial mats indicated that the uppermost layers of the mats contained fungal biomarker, 18:2w6. This fatty acid decreased with depth, the highest concentration was observed in the green upper layer and it disappeared in the black bottom anoxic layer. This correlates with the isolation of fungi using the serial dilution technique. This is the first study that documents the presence of fungi in microbial mats. PMID:16904880

Cantrell, Sharon A; Casillas-Martínez, Lilliam; Molina, Marirosa

2006-08-01

239

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

240

Abnormal enteric nerve morphology in atretic esophagus of fetal rats with adriamycin-induced esophageal atresia.  

PubMed

Gastroesophageal reflux is common in children after successful repair of esophageal atresia (EA), and may be related to a congenital neuronal abnormality of the esophagus. This study employed a fetal rat model of adriamycin-induced EA to investigate whether the innervation of the esophagus is abnormal in EA. The fetal rats were divided into four groups: (1) normal controls; (2) a saline-injected controls; (3) adriamycin administered but without the development of EA; and (4) adriamycin-induced EA. The distal esophageal segments were immunostained with a general neural marker, protein gene product 9.5 (PGP). Immunoreactivity per cross-sectional area (/xsa) was measured with an image analyzer. The extent of the esophageal circumference encircled by PGP-stained nerve tissue was assessed. While there was no significant difference in PGP immunoreactivity/xsa between the groups, the near-complete ring of nerve tissue along the plane of the myenteric plexus was replaced by clusters of nerve tissue in the atretic group (normal vs EA, P = 0. 001, Mann-Whitney U test). The abnormal distribution of nerve tissue in the atretic esophagus may be contributing factor in the esophageal dysmotility seen in EA. PMID:9914345

Cheng, W; Bishop, A E; Spitz, L; Polak, J M

1999-01-01

241

Mesenchymal Stem Cells Improved the Ultrastructural Morphology of Cerebral Tissues after Subarachnoid Hemorrhage in Rats  

PubMed Central

Subarachnoid hemorrhage (SAH) causes widespread disruption in the cerebral architecture.The process of SAH is complicated and many people lose their lives or become disabled after injury. Mesenchymal stem cells (MSCs) are considered as good candidate for repair of cerebral damage. The aim was to assess the ultrastructural changes in the rat cerebral tissue after intravenous transplantation of MSCs. Female Wistar rats (8 per group) weighing 275~300 g were assigned to control (SAH+PBS) and experimental groups (SAH+MSCs).The samples from middle cerebral arterial wall and parietal cerebral tissue were prepared for transmission electron microscopy (TEM) according to standard protocol. Fine architectures of the vessel wall, including the contraction of the inner layer, smooth muscle layer,as well as neural cells were observed after SAH. Cerebral arterial wall and cortex, including neuronal and glial cells were injured post SAH. But, administration of MSCs improved the structural integrity of cerebral tissues. Changes were much more balanced with their relative improvement in some areas. The role of MSCs for repairing the injured cerebral tissues post experimental SAH was approved by electron microscopy. PMID:24737942

Khalili, Mohammad Ali; Fesahat, Farzaneh; Mir-Esmaeili, Seyed Mohsen; Anvari, Morteza; Hekmati-moghadam, Seyed Hossain

2014-01-01

242

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

243

Characterization of the development of renal injury in Type-1 diabetic Dahl salt-sensitive rats  

PubMed Central

The present study compared the progression of renal injury in Sprague-Dawley (SD) and Dahl salt-sensitive (SS) treated with streptozotocin (STZ). The rats received an injection of STZ (50 mg/kg ip) and an insulin pellet (2 U/day sc) to maintain the blood glucose levels between 400 and 600 mg/dl. Twelve weeks later, arterial pressure (143 ± 6 vs. 107 ± 8 mmHg) and proteinuria (557 ± 85 vs. 81 ± 6 mg/day) were significantly elevated in STZ-SS rats compared with the values observed in STZ-SD rats, respectively. The kidneys from STZ-SS rats exhibited thickening of glomerular basement membrane, mesangial expansion, severe glomerulosclerosis, renal interstitial fibrosis, and occasional glomerular nodule formation. In additional studies, treatment with a therapeutic dose of insulin (4 U/day sc) attenuated the development of proteinuria (212 ± 32 mg/day) and renal injury independent of changes in arterial pressure in STZ-SS rats. Since STZ-SS rats developed severe renal injury, we characterized the time course of changes in renal hemodynamics during the progression of renal injury. Nine weeks after diabetes onset, there was a 42% increase in glomerular filtration rate in STZ-SS rats vs. time-control SS rats with reduced renal blood flow. These results indicate that SS rats treated with STZ develop hyperfiltration and progressive proteinuria and display renal histological lesions characteristic of those seen in patients with diabetic nephropathy. Overall, this model may be useful to study signaling pathways and mechanisms that play a role in the progression of diabetes-induced renal disease and the development of new therapies to slow the progression of diabetic nephropathy. PMID:23926133

Slaughter, Tiffani N.; Paige, Adrienne; Spires, Denisha; Kojima, Naoki; Kyle, Patrick B.; Garrett, Michael R.; Roman, Richard J.

2013-01-01

244

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...

245

Characterization of glycoconjugates in developing rat respiratory system by means of conventional and lectin histochemistry  

Microsoft Academic Search

The glycoconjugates of the respiratory system of rats from 15 days of gestation through the adult period have been characterized by means of both conventional and lectin histochemistry. The main changes occurred at 20–21 days of gestation immediately before birth. An increase of acidic groups in the glycoproteins of the lung and airway epithelium was observed by conventional mucin histochemistry.

M. T. Castells; J. Ballesta; J. F. Madrid; M. Aviles; J. A. Martinez-Menarguez

1991-01-01

246

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

247

Changes in the morphology and the distribution of rat intestinal eosinophils during infection with the nematode Nippostrongylus brasiliensis.  

PubMed

Increases in the numbers of eosinophil leukocytes present in the lamina propria of intestines infected with nematodes is a well described phenomenon, yet the role of these leukocytes and their actions in this situation are not yet fully understood. Morphologic changes in these cells occur with the course of the infection, as do alterations in their location within the gut; these findings may give important clues to the function of this prominent cell. We observed changes in intestinal eosinophils in the August rat during infection with the nematode Nippostrongylus brasiliensis and found, together with the well known increases in number infiltrating the lamina propria at Day 20 (three times the levels in normal animals), a distinct change in the morphology of individual cells which included increase of the cell's overall size and changes in shape, as well as a dissemination of cytoplasmic granules in relationship to the cell's nucleus. No ultrastructural evidence of extracellular degranulation or intact eosinophil cytoplasmic granules outside the bounds of cell cytoplasmic membranes was seen. This finding is important considering the light microscopic appearance of individual eosinophil granules apparently distributed extracellularly, and lying in the connective tissue of the lamina propria, a common histopathologic observation in eosinophilic conditions. Eosinophils within the lamina propria changed their location as the infection progressed, tending to move to line up along the subepithelial zones. In addition, eosinophils were observed both at the light and electron microscopic levels to be passing through the basement membrane and into the epithelial layer. This latter phenomenon was confirmed using confocal optical slicing where eosinophils were commonly observed on the luminal side of the nuclei of the gut epithelium. These observations strongly suggest that morphologic alterations occur in eosinophils in the lamina propria and these changes may be associated with functional alterations in these cells akin to the putative phenomenon of "activation." Our findings indicate that eosinophils have the capacity to enlarge and extend their cytoplasmic processes between various components of the lamina propria and move toward the basement membrane during an active infection, as well as into, and possibly through, the intestinal epithelium. These findings emphasize the need for careful consideration of the changing morphologic status of eosinophils when investigating biologic changes associated with the activation of these cells in tissue inflammatory responses. PMID:10418819

Eversole, R; Mackenzie, C; Conder, G; Johnson, S; Beuving, L

1999-07-01

248

Progesterone and its derivatives dihydroprogesterone and tetrahydroprogesterone reduce myelin fiber morphological abnormalities and myelin fiber loss in the sciatic nerve of aged rats.  

PubMed

Previous studies indicate that steroid hormones may be protective for Schwann cells and promote the expression of myelin proteins in the sciatic nerve of adult rats. In this study, we have evaluated the effect of progesterone (P), dihydroprogesterone (DHP), tetrahydroprogesterone (THP), testosterone (T), dihydrotestosterone (DHT) and 5alpha-androstan-3alpha, 17beta-diol (3alpha-diol) on the morphological alterations of myelinated fibers in the sciatic nerve of 22-24-month-old male rats. The sciatic nerves of untreated old male rats, showed a general disorganization and a significant reduction in the density of myelinated fibers, compared to nerves from 3-month-old male rats. The effect of aging was particularly evident in myelinated fibers of small caliber (<5 microm in diameter). In addition, the sciatic nerves of old rats showed a significant increase in the number of fibers with myelin infoldings in the axoplasm and in the number of fibers with irregular shapes. Treatments of old rats with P, DHP and THP resulted in a significant increase in the number of myelinated fibers of small caliber, a significant reduction in the frequency of myelin abnormalities and a significant increase in the g ratio of small myelinated fibers. Furthermore, P treatment significantly reduced the frequency of myelinated fibers with irregular shapes. In contrast, treatments with T, DHT or 3alpha-diol did not significantly affect any of the morphological parameters examined. In conclusion, our data indicate that P, and its derivatives DHP and THP, are able to reduce aging-associated morphological abnormalities of myelin and aging-associated myelin fiber loss in the sciatic nerve. These data suggest that P, DHP and THP may represent useful therapeutic alternatives to maintain peripheral nerve integrity in aged animals. PMID:12927767

Azcoitia, Iñigo; Leonelli, Emanuela; Magnaghi, Valerio; Veiga, Sergio; Garcia-Segura, Luis M; Melcangi, Roberto C

2003-10-01

249

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

SciTech Connect

Highlights: > Particle size distributions and total concentrations measurement at the stack and before the fabric filter of an incinerator. > Chemical characterization of UFPs in terms of heavy metal concentration through a nuclear method. > Mineralogical investigation through a Transmission Electron Microscope equipped with an Energy Dispersive Spectrometer. > Heavy metal concentrations on UFPs as function of the boiling temperature. > Different mineralogical and morphological composition amongst samples collected before the fabric filter and at the stack. - Abstract: 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 {mu}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 x 10{sup 7} part. cm{sup -3} and 2.0 x 10{sup 3} part. cm{sup -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.

Buonanno, Giorgio, E-mail: buonanno@unicas.it [University of Cassino, via G. Di Biasio 43, 03043 Cassino (Italy); Stabile, Luca [University of Cassino, via G. Di Biasio 43, 03043 Cassino (Italy); Avino, Pasquale [DIPIA, INAIL (ex-ISPESL), via Urbana 167, 00184 Rome (Italy); Belluso, Elena [Dipartimento di Scienze Mineralogiche e Petrologiche, University of Torino and Institute of Geosciences and Earth Resources, CNR-Unita di Torino, via Valperga Caluso 35, 10125 Torino (Italy)

2011-11-15

250

Hepatic morphological alterations, glycogen content and cytochrome P450 activities in rats treated chronically with N ? -nitro-L-arginine methyl ester (L-NAME)  

Microsoft Academic Search

Chronic treatment of rats with N?-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide (NO) biosynthesis, results in hypertension mediated\\u000a partly by enhanced angiotensin-I-converting enzyme (ACE) activity. We examined the influence of L-NAME on rat liver morphology,\\u000a on hepatic glycogen, cholesterol, and triglyceride content, and on the activities of the cytochrome P450 isoforms CYP1A1\\/2,\\u000a CYP2B1\\/2, CYP2C11, and CYP2E1. Male Wistar

Christiane Aparecida Badin Tarsitano; Valdemar A. Paffaro; José Rodrigo Pauli; Gustavo Henrique da Silva; Mario J. Saad; Ione Salgado; Maria Alice da Cruz-Höfling; Stephen Hyslop

2007-01-01

251

Morphology of the lingual papillae in the brush-tailed rat kangaroo.  

PubMed

We examined the dorsal lingual surface of an adult brush-tailed rat kangaroo (Bettongia penicillata) by scanning electron microscopy. The filiform and fungiform papillae on the lingual apex and body consisted of a main papilla and secondary papillae. The connective tissue core of the filiform papillae on the lingual apex was cylindrical in shape with a crushed top. The connective tissue core of the filiform papillae on the lingual body had one large and several small processes. The fungiform papillae were round in shape. The connective tissue core of the fungiform papillae had several depressions on its top. The surface of the vallate papillae was rough and the papillae were surrounded by a groove and a pad. Several long conical papillae derived from the posterolateral margin of the tongue where foliate papillae have been shown to be distributed in many other animal species. The long conical papillae were very similar to those of the koala and opossum. PMID:24815106

Emura, Shoichi; Okumura, Toshihiko; Chen, Huayue

2014-01-01

252

Application of polarization microscopy for the nonstained determination of myo-lamina morphology in the rat  

NASA Astrophysics Data System (ADS)

The remodeling of cardiac tissues has been implicated in the development of congestive heart failure. Therefore, the current emphasis in cardiovascular research is geared toward understanding the underlying processes in order to facilitate the development of better prevention and treatment regimens by improving the early detection and diagnosis of this disease. This paper focuses on the application of polarized light to address a major drawback of cardiovascular biomechanics research, which is the utilization of toxic chemicals to prepare samples for histological examination. To accomplish this without the use of toxic chemicals, a polarization microscopy imaging technique was developed and applied to a non-stained rat septum sample. This imaging technique provided sufficient enhancement of collagenous structures to determine the myo-lamina sheet angle, ?, without the need for caustic staining.

Baba, Justin S.; Criscione, John C.; Hudson, Kristen K.; Cote, Gerard L.

2004-06-01

253

Prenatal exposure to tobacco extract containing nicotinic alkaloids produces morphological and behavioral changes in newborn rats.  

PubMed

Tobacco exposure is not only a health concern for adults but has also been shown to exert deleterious effects on the health of the fetus, newborn, child, and adolescent. Decreased cognitive function, lower Intellectual Quotient (IQ) and deficits in learning and memory in children have been associated with maternal smoking during pregnancy. In this study, we have studied the effect of a tobacco plant extract on the growth and development in the rat. The extract contained relative proportions of alkaloids, including nicotine, purified by chemical separation. Pregnant rats received oral doses of either control (NaCl) or tobacco extract during the entire gestational period. Offspring length and body weight were measured. Each day, the offspring were observed for the following physical parameters: hair growth, incisor eruption and eye opening. The day of appearance of these developments was recorded. Before weaning, the offspring were examined to test their cliff avoidance response (6 postnatal day (PN)), surface righting reflex (05, 07, 13 postnatal day), swimming development (10, 12 postnatal day), negative geotaxis response (7,9,13 and 17 postnatal day) and jumping down choice cage (15, 17 postnatal day). Administration of tobacco extract to dams during the entire gestation period affects behavior and development in pups. The observed effects were a delay in opening eyes, incisor eruption and hair appearance, behavioral developments and an alteration in the rate of success behavior. However, in the jumping down choice cage test there was no difference compared to control animals. The results suggest that tobacco extract has a significant effect on the development of behavioral patterns, orientation and motor coordination and function. They also suggest significant growth retardation and teratogenic effects. PMID:22306748

Khalki, Hanane; Khalki, Loubna; Aboufatima, Rachida; Ouachrif, Abderrahim; Mountassir, Maryam; Benharref, Ahmed; Chait, Abderrahman

2012-05-01

254

Fenitrothion induced oxidative stress and morphological alterations of sperm and testes in male sprague-dawley rats  

PubMed Central

OBJECTIVE: Fenitrothion residue is found primarily in soil, water and food products and can lead to a variety of toxic effects on the immune, hepatobiliary and hematological systems. However, the effects of fenitrothion on the male reproductive system remain unclear. This study aimed to evaluate the effects of fenitrothion on the sperm and testes of male Sprague-Dawley rats. METHODS: A 20 mg/kg dose of fenitrothion was administered orally by gavages for 28 consecutive days. Blood sample was obtained by cardiac puncture and dissection of the testes and cauda epididymis was performed to obtain sperm. The effects of fenitrothion on the body and organ weight, biochemical and oxidative stress, sperm characteristics, histology and ultrastructural changes in the testes were evaluated. RESULTS: Fenitrothion significantly decreased the body weight gain and weight of the epididymis compared with the control group. Fenitrothion also decreased plasma cholinesterase activity compared with the control group. Fenitrothion altered the sperm characteristics, such as sperm concentration, sperm viability and normal sperm morphology, compared with the control group. Oxidative stress markers, such as malondialdehyde, protein carbonyl, total glutathione and glutathione S-transferase, were significantly increased and superoxide dismutase activity was significantly decreased in the fenitrothion-treated group compared with the control group. The histopathological and ultrastructural examination of the testes of the fenitrothion-treated group revealed alterations corresponding with the biochemical changes compared with the control group. CONCLUSION: A 20 mg/kg dose of fenitrothion caused deleterious effects on the sperm and testes of Sprague-Dawley rats. PMID:23420164

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

2013-01-01

255

Morphologic evidence that neurokinin B modulates gonadotropin-releasing hormone secretion via neurokinin 3 receptors in the rat median eminence.  

PubMed

Recent studies suggest that arcuate neurokinin B (NKB) neurons play a role in the regulation of gonadotropin secretion, but there is little information on the relationship between these neurons and the hypothalamic reproductive axis. In the present study, dual-label fluorescent immunohistochemistry was used to visualize the relationship between gonadotropin-releasing hormone (GnRH) neurons and either proNKB or NK3 receptor (NK3R) immunoreactivity. Immunocytochemistry was also combined with i.p. injections of the fluorescent retrograde tracer aminostilbamidine to determine whether arcuate neuroendocrine neurons expressed either proNKB or NK3R. A dense interweaving and close apposition of GnRH and proNKB-immunoreactive (ir) fibers was observed within the rat median eminence, where GnRH axons expressed NK3R immunoreactivity. These data provide morphological evidence that NKB neurons could influence GnRH secretion via interaction with NK3R in the rat median eminence. Colocalization of GnRH and NK3R was also identified in fiber tracts converging within the organum vasculosum of the lamina terminalis. In contrast, only a small number (16%) of GnRH-ir somata exhibited NK3R staining. ProNKB and NK3R-ir somata were identified within the arcuate nucleus, but none of these neurons were labeled by aminostilbamidine. Thus, we found no evidence that arcuate NKB neurons project to the primary capillary plexus of the portal system. Arcuate neuroendocrine neurons, however, were surrounded and closely apposed by proNKB-ir puncta and fibers. These data suggest that NKB neurons could indirectly influence anterior pituitary function by inputs to arcuate neuroendocrine neurons, but through a receptor other than NK3R. Our results provide an anatomic framework for putative interactions between NKB neurons and the hypothalamic reproductive axis. PMID:16025449

Krajewski, Sally J; Anderson, Miranda J; Iles-Shih, Lulu; Chen, Kyung J; Urbanski, Henryk F; Rance, Naomi E

2005-08-29

256

Insulin and glucagon secretions, and morphological change of pancreatic islets in OLETF rats, a model of type 2 diabetes mellitus.  

PubMed Central

This study was performed to observe the changes of glucose-related hormones and the morphological change including ultrastructure of the pancreatic islets in the male Otsuka Long-Evans Tokushima Fatty rat. Area under the curve (AUC) of glucose at the 30th (709 plus minus 73 mg.h/dL) and at the 40th week (746 plus minus 87 mg.h/ dL) of age were significantly higher than that at the 10th week (360 plus minus 25 mg.h/ dL). AUC of insulin of the 10th week was 2.4 plus minus 0.9 ng.h/mL, increased gradually to 10.8 plus minus 8.3 ng.h/mL at the 30th week, and decreased to 1.8 plus minus 1.2 ng.h/mL at the 40th week. The size of islet was increased at 20th week of age and the distribution of peripheral alpha cells and central beta cells at the 10th and 20th weeks was changed to a mixed pattern at the 40th week. On electron microscopic examination, beta cells at the 20th week showed many immature secretory granules, increased mitochondria, and hypertrophied Golgi complex and endoplasmic reticulum. At the 40th week, beta cell contained scanty intracellular organelles and secretory granules and apoptosis of acinar cell was observed. In conclusion, as diabetes progressed, increased secretion of insulin was accompanied by increases in size of islets and number of beta-cells in male OLETF rats showing obese type 2 diabetes. However, these compensatory changes could not overcome the requirement of insulin according to the continuous hyperglycemia after development of diabetes. PMID:11850586

Hong, Eun Gyoung; Noh, Hye Lim; Lee, Seong Kyu; Chung, Yoon Sok; Lee, Kwan Woo; Kim, Hyeon Man

2002-01-01

257

Morphology, Classification, and Distribution of the Projection Neurons in the Dorsal Lateral Geniculate Nucleus of the Rat  

PubMed Central

The morphology of confirmed projection neurons in the dorsal lateral geniculate nucleus (dLGN) of the rat was examined by filling these cells retrogradely with biotinylated dextran amine (BDA) injected into the visual cortex. BDA-labeled projection neurons varied widely in the shape and size of their cell somas, with mean cross-sectional areas ranging from 60–340 µm2. Labeled projection neurons supported 7–55 dendrites that spanned up to 300 µm in length and formed dendritic arbors with cross-sectional areas of up to 7.0×104 µm2. Primary dendrites emerged from cell somas in three broad patterns. In some dLGN projection neurons, primary dendrites arise from the cell soma at two poles spaced approximately 180° apart. In other projection neurons, dendrites emerge principally from one side of the cell soma, while in a third group of projection neurons primary dendrites emerge from the entire perimeter of the cell soma. Based on these three distinct patterns in the distribution of primary dendrites from cell somas, we have grouped dLGN projection neurons into three classes: bipolar cells, basket cells and radial cells, respectively. The appendages seen on dendrites also can be grouped into three classes according to differences in their structure. Short “tufted” appendages arise mainly from the distal branches of dendrites; “spine-like” appendages, fine stalks with ovoid heads, typically are seen along the middle segments of dendrites; and “grape-like” appendages, short stalks that terminate in a cluster of ovoid bulbs, appear most often along the proximal segments of secondary dendrites of neurons with medium or large cell somas. While morphologically diverse dLGN projection neurons are intermingled uniformly throughout the nucleus, the caudal pole of the dLGN contains more small projection neurons of all classes than the rostral pole. PMID:23139837

Ling, Changying; Hendrickson, Michael L.; Kalil, Ronald E.

2012-01-01

258

Morphology and distribution of electrophysiologically defined classes of pyramidal and nonpyramidal neurons in rat ventral subiculum in vitro.  

PubMed

Intracellular electrophysiological recordings were made from 210 ventral subicular neurons in rat brain slices. Recordings were classified as burst-firing or nonburst-firing. Eighteen burst-firing neurons were filled with Neurobiotin, and all had pyramidal morphology. Nine of these recordings were made from intrinsically burst-firing (IB) cell bodies, and nine were made from burst-firing dendrites (BD). Twelve nonburst-firing neurons were also filled with Neurobiotin. Eight were regular spiking (RS) and had pyramidal morphology, four were fast spiking (FS) and nonpyramidal. Additional electrophysiological parameters distinguished IB from BD, RS from FS, and RS from IB recordings. The distribution of IB and RS neurons was examined by using 180 recordings. Information from the first series of experiments was used to distinguish between somatic and dendritic recordings. The deep-superficial axis (alveus-hippocampal fissure) was divided into four equal rows. RS neurons accounted for 12%, 28%, 58%, and 50% of presumed somatic recordings in successively more superficial rows. The proximal-distal (CA1-perforant path) axis was divided into five equal columns. RS cells accounted for 52% of presumed somatic impalements in the central column compared with 16% in the most proximal and 10% in the most distal columns. Thus, two electrophysiological classes of pyramidal neuron were localized to particular regions of the ventral subiculum. In the light of existing knowledge of the topography of subicular inputs and outputs, our results are consistent with the hypothesis that the ratio of RS to IB pyramidal neurons will be different in different transhippocampal circuits. PMID:9087521

Greene, J R; Totterdell, S

1997-04-14

259

Identification and morphologic and molecular characterization of Cyclospora macacae n. sp. from rhesus monkeys in China.  

PubMed

Cyclospora spp. in nonhuman primates are most closely related to Cyclospora cayetanensis, an emerging human pathogen causing outbreaks of cyclosporiasis in North America. Studies thus far indicate the possible existence of host specificity in Cyclospora spp. In this study, 411 fecal specimens from free-range rhesus monkeys (Macaca mulatta) were collected and examined for Cyclospora by sequence analysis of the small subunit rRNA gene. A novel Cyclospora species was identified in 28 (6.8 %) specimens and named Cyclospora macacae based on morphologic and molecular characterizations. The oocyst of C. macacae is spherical and measures 8.49?±?0.55?×?8.49?±?0.49 ?m in diameter. Phylogenetic analysis grouped this species together with the other four Cyclospora species infecting primates, including C. cayetanensis in humans, forming a monophyletic group closely related to avian Eimeria species. In addition, C. cayetanensis was detected in one specimen, although whether rhesus monkeys can serve as a natural reservoir host of C. cayetanensis needs further investigation. PMID:25673080

Li, Na; Ye, Jianbin; Arrowood, Michael J; Ma, Jingbo; Wang, Lin; Xu, Hailing; Feng, Yaoyu; Xiao, Lihua

2015-05-01

260

Somatic hybridization by microfusion of defined protoplast pairs in Nicotiana: morphological, genetic, and molecular characterization.  

PubMed

Somatic hybrid/cybrid plants were obtained by microfusion of defined protoplast pairs from malefertile, streptomycin-resistant Nicotiana tabacum and cytoplasmic male-sterile (cms), streptomycin-sensitive N. tabacum cms (N. bigelovii) after microculture of recovered fusants. Genetic and molecular characterization of the organelle composition of 30 somatic hybrid/cybrid plants was performed. The fate of chloroplasts was assessed by an in vivo assay for streptomycin resistance/ sensitivity using leaf explants (R0 generation and R1 seedlings). For the analysis of the mitochondrial (mt) DNA, species-specific patterns were generated by Southern hybridization of restriction endonuclease digests of total DNA and mtDNA, with three DNA probes of N. sylvestris mitochondrial origin. In addition, detailed histological and scanning electron microscopy studies on flower ontogeny were performed for representative somatic hybrids/cybrids showing interesting flower morphology. The present study demonstrates that electrofusion of individually selected pairs of protoplasts (microfusion) can be used for the controlled somatic hybridization of higher plants. PMID:24221062

Spangenberg, G; Osusky, M; Oliveira, M M; Freydl, E; Nagel, J; Pais, M S; Potrykus, I

1990-11-01

261

Molecular and morphological characterization of mealybugs (Hemiptera: Pseudococcidae) from Chilean vineyards.  

PubMed

Mealybugs are major pests of grapevines worldwide. They cause economic losses by lowering the cosmetic value of fruits, reducing yields, transmitting viruses and resulting in the quarantine or rejection of produce in international trade. Knowledge of the species present in a vineyard is important for the adjustment of management strategies. We surveyed and accurately characterized the mealybugs infesting vineyards in one of the main production areas of Chile; 164 mealybugs were sampled from 26 vineyards in four regions of Chile and identified by DNA sequencing for two markers (cytochrome oxidase I and internal transcribed spacer 2) and morphological examination. Pseudococcus viburni (Signoret) was the most common species, followed by Pseudococcus meridionalis Prado and Pseudococcus cribata González. Molecular variability at the COI and ITS2 loci was observed in both P. viburni and P. cribata. A comparison of haplotypes of P. viburni worldwide provides support for a recent hypothesis that this species is native to South America, a finding with direct consequences for management. Neither Pseudococcus longispinus (Targioni & Tozzetti) nor Planococcus ficus Signoret were found. PMID:22361038

Correa, M C G; Germain, J-F; Malausa, T; Zaviezo, T

2012-10-01

262

High-precision characterization of individual E. coli cell morphology by scanning flow cytometry.  

PubMed

We demonstrate a flow-cytometric method to measure length and diameter of single Escherichia coli cells with sub-diffraction precision. The method is based on the original scanning flow cytometer that measures angle-resolved light-scattering patterns (LSPs) of individual particles. We modeled the shape of E. coli cells as a cylinder capped with hemispheres of the same radius, and simulated light scattering by the models using the discrete dipole approximation. We computed a database of the LSPs of individual bacteria in a wide range of model parameters and used it to solve the inverse light-scattering problem by the nearest-neighbor interpolation. The solution allows us to determine length and diameter of each individual bacterium, including uncertainties of these estimates. The developed method was tested on two strains of E. coli. The resulting precision of bacteria length and diameter measurements varied from 50 nm to 250 nm and from 5 nm to 25 nm, respectively. The measured distributions of samples over length and diameter were in good agreement with measurements performed by optical microscopy and literature data. The described approach can be applied for rapid morphological characterization of any rod-shaped bacteria. PMID:23568828

Konokhova, Anastasiya I; Gelash, Andrey A; Yurkin, Maxim A; Chernyshev, Andrey V; Maltsev, Valeri P

2013-06-01

263

Multistep Aggregation Pathway of Human Interleukin-1 Receptor Antagonist: Kinetic, Structural, and Morphological Characterization  

PubMed Central

Abstract The complex, multistep aggregation kinetic and structural behavior of human recombinant interleukin-1 receptor antagonist (IL-1ra) was revealed and characterized by spectral probes and techniques. At a certain range of protein concentration (12–27 mg/mL) and temperature (44–48°C), two sequential aggregation kinetic transitions emerge, where the second transition is preceded by a lag phase and is associated with the main portion of the aggregated protein. Each kinetic transition is linked to a different type of aggregate population, referred to as type I and type II. The aggregate populations, isolated at a series of time points and analyzed by Fourier-transform infrared spectroscopy, show consecutive protein structural changes, from intramolecular (type I) to intermolecular (type II) ?-sheet formation. The early type I protein spectral change resembles that seen for IL-1ra in the crystalline state. Moreover, Fourier-transform infrared data demonstrate that type I protein assembly alone can undergo a structural rearrangement and, consequently, convert to the type II aggregate. The aggregated protein structural changes are accompanied by the aggregate morphological changes, leading to a well-defined population of interacting spheres, as detected by scanning electron microscopy. A nucleation-driven IL-1ra aggregation pathway is proposed, and assumes two major activation energy barriers, where the second barrier is associated with the type I ? type II aggregate structural rearrangement that, in turn, serves as a pseudonucleus triggering the second kinetic event. PMID:19134476

Krishnan, Sampathkumar; Raibekas, Andrei A.

2009-01-01

264

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

265

2.5D constructs for characterizing phase separated polymer blend surface morphology in tissue engineering scaffolds.  

PubMed

Previously, we used 2D films to identify an annealed PCL-PDLLA phase-separated blend morphology which provided nanoscale surface texture and patterning that stimulated osteoblast differentiation. In order to translate these 2D surface nanopatterning effects to the walls of 3D salt-leached scaffolds, the blend phase morphology of scaffold walls must be characterized. For salt-leached scaffolds, NaCl is used as a porogen, which may affect phase separation in PCL-PDLLA blends. However, it is not possible to characterize the surface blend morphology of 3D scaffold walls using standard approaches such as AFM or optical microscopy, since scaffolds are too rough for AFM and do not transmit light for optical microscopy. We introduce a 2.5D approach that mimics the processing conditions of 3D salt-leached scaffolds, but has a geometry amenable to surface characterization by AFM and optical microscopy. For the 2.5D approach, PCL-PDLLA blend films were covered with NaCl crystals prior to annealing. The presence of NaCl significantly influenced blend morphology in PCL-PDLLA 2.5D constructs causing increased surface roughness, higher percent PCL area on the surface and a smaller PCL domain size. During cell culture on 2.5D constructs, osteoblast (MC3T3-E1) and dermal endothelial cell (MDEC) adhesion were enhanced on PCL-PDLLA blends that were annealed with NaCl while chondrogenic cell (ATDC5) adhesion was diminished. This work introduces a 2.5D approach that mimicked 3D salt-leached scaffold processing, but enabled characterization of scaffold surface properties by AFM and light microscopy, to demonstrate that the presence of NaCl during annealing strongly influenced polymer blend surface morphology and cell adhesion. PMID:23184520

Marszalek, Jolanta E; Simon, Carl G; Thodeti, Charles; Adapala, Ravi Kumar; Murthy, Ananth; Karim, Alamgir

2013-05-01

266

Morphometrical characterization of two glioma models in the brain of immunocompetent and immunodeficient rats.  

PubMed

Although several glioma models exist, systematic morphometrical studies on such experimental tumors are lacking. The purpose of this study was the quantitative assessment of how rat strains, cell lines, injection techniques and location affect tumors reproducibility and histopathological features. Glioma cells were implanted in 3 brain locations, with different injection techniques (free hand, stereotactic, water-tight device), variable volumes, cell concentrations and infusion rates. Tumors were developed from 2 rat glioma cell lines (9L and C6) in immunocompetent (Wistar and Fischer 344) and immunodeficient rats (New Zealand). Animals underwent daily neurological examination. At the scheduled time the tumors were macro and microscopically evaluated and a quantitative morphometrical analysis was performed. C6 gliomas appeared very infiltrative and irregularly shaped; 9L gliomas showed, by using the same injection technique, a grossly regular shape. Margins at the tumor-brain interface were macroscopically demarcated in the immunocompetent rats. In the nude rats, 9L tumors appeared microscopically more infiltrative, although regularly shaped, with a closer morphological resemblance to human gliomas. The implantation in the frontal area, anterior to the nucleus caudatus (3 mm anterior the coronal suture) gave reproducible tumor shape and size, no hydrocephalus and no early neurological deterioration. The use of a stereotactic technique or of a water-tight device, small volume (< 10 microl) of cell suspension, low infusion rate were useful to reduce morbidity and to improve data reproducibility. No difference in morbidity and mortality were observed in immunocompetent and immunodeficient rats. The 9L glioma model with stereotactic implantation constitutes a good option for reliable morphometrical evaluation of tumor growth. We propose a location for tumor implantation anterior to the nucleus caudatus. This produced the longest symptom-free survival. PMID:10360479

Saini, M; Bellinzona, M; Meyer, F; Cali, G; Samii, M

1999-03-01

267

Chemical and morphological characterization of III-V strained layered heterostructures  

NASA Astrophysics Data System (ADS)

This dissertation describes investigations into the chemical and morphological characterization of III-V strained layered heterostructures by high-resolution x-ray diffraction. The purpose of this work is two-fold. The first was to use high-resolution x-ray diffraction coupled with transmission electron microscopy to characterize structurally a quaternary AlGaAsSb/InGaAsSb multiple quantum well heterostructure laser device. A method for uniquely determining the chemical composition of the strain quaternary quantum well, information previously thought to be unattainable using high resolution x-ray diffraction is thoroughly described. The misconception that high-resolution x-ray diffraction can separately find the well and barrier thickness of a multi-quantum well from the pendellosung fringe spacing is corrected, and thus the need for transmission electron microscopy is motivated. Computer simulations show that the key in finding the well composition is the intensity of the -3rd order satellite peaks in the diffraction pattern. The second part of this work addresses the evolution of strain relief in metastable multi-period InGaAs/GaAs multi-layered structures by high-resolution x-ray reciprocal space maps. Results are accompanied by transmission electron and differential contrast microscopy. The evolution of strain relief is tracked from a coherent "pseudomorphic" growth to a dislocated state as a function of period number by examining the x-ray diffuse scatter emanating from the average composition (zeroth-order) of the multi-layer. Relaxation is determined from the relative positions of the substrate with respect to the zeroth-order peak. For the low period number, the diffuse scatter from the multi-layer structure region arises from periodic, coherent crystallites. For the intermediate period number, the displacement fields around the multi-layer structure region transition to random coherent crystallites. At the higher period number, displacement fields of overlapping dislocations from relaxation of the random crystallites cause the initial stages of relaxation of the multi-layer structure. At the highest period number studied, relaxation of the multi-layer structure becomes bi-modal characterized by overlapping dislocations caused by mosaic block relaxation and periodically spaced misfit dislocations formed by 60°-type dislocations. The relaxation of the multi-layer structure has an exponential dependence on the diffuse scatter length-scale, which is shown to be a sensitive measure of the onset of relaxation.

Gray, Allen Lindsay

268

Study of heparin in intestinal ischemia and reperfusion in rats: morphologic and functional evaluation.  

PubMed

To study whether treatment with heparin (HEP) attenuates intestinal dysfunction caused by ischemia (I) and reperfusion (R), rats were treated with HEP (100 U/kg intravenously) or saline solution (SS) before I (60 min), which was produced by occlusion of the superior mesenteric artery, and R (120 min). After I or I/R, we mounted 2-cm jejunal segment in an organ bath to study neurogenic contractions stimulated by electrical pulses or KCl, using a digital recording system. Thin jejunal slices were stained with hematoxylin and eosin for optical microscopy. Compared with the sham group, jejunal contractions were similar in the I + HEP and the I/R + HEP groups, but reduced in the I + SS and the I/R + SS groups. The jejunal enteric nerves were damaged in the I + SS and the I/R + SS, but not in the I + HEP and the I/R + HEP cohorts. These results suggested that HEP attenuated intestinal dysfunction caused by I and I/R. PMID:23026579

Ghadie, M M; Miranda-Ferreira, R; Taha, N S A; Maroso, A S; Moreti, R J Z; Andraus, M P; Zempulski, P; Monteiro, H P; Simões, M J; Fagundes, D J; Caricati-Neto, A; Taha, M O

2012-10-01

269

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

270

Autonomic innervation of tendons, ligaments and joint capsules. A morphologic and quantitative study in the rat.  

PubMed

We analyzed the neuronal occurrence of autonomic transmitters; noradrenaline (NA), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP), in the Achilles tendon, medial and lateral collateral ligaments and knee joint capsule in the rat--by immunohistochemistry (IHC). In addition, the tissue concentrations of the sympathetic neuropeptide, NPY, and the parasympathetic peptide, VIP, were determined by radioimmunoassay (RIA). IHC demonstrated nerve fibers containing sympathetic vasoconstrictors--NA and NPY--and the parasympathetic vasodilator, VIP, in all tissues. NPY- and NA-positive nerve fibers were predominantly observed in larger blood vessels, whereas, nerve fibers immunoreactive to VIP were found in smaller vessels. In many nerve fibers a co-localization of the transmitters was seen. RIA showed that the concentration of NPY compared to VIP was 15-times higher in ligaments and twice as high in tendons and capsules. The differences noted may reflect a difference in vulnerability to degenerative conditions. In pathological conditions, dysregulation of autonomic transmitters in hypovascularized tissues subjected to repetitive mechanical load may contribute to tissue hypoxia leading to degeneration and rupture of tendons and ligaments. PMID:11398848

Ackermann, P W; Li, J; Finn, A; Ahmed, M; Kreicbergs, A

2001-05-01

271

Characterization of biliary conjugates of 4,4'-methylenedianiline in male versus female rats  

SciTech Connect

4,4'-Methylenedianiline (4,4'-diaminodiphenylmethane; DAPM) is an aromatic diamine used in the production of numerous polyurethane foams and epoxy resins. Previous studies in rats revealed that DAPM initially injures biliary epithelial cells of the liver, that the toxicity is greater in female than in male rats, and that the toxic metabolites of DAPM are excreted into bile. Since male and female rats exhibit differences in the expression of both phase I and phase II enzymes, our hypothesis was that female rats either metabolize DAPM to more toxic metabolites or have a decreased capacity to conjugate metabolites to less toxic intermediates. Our objective was thus to isolate, characterize, and quantify DAPM metabolites excreted into bile in both male and female bile duct-cannulated Sprague Dawley rats. The rats were gavaged with [{sup 14}C]-DAPM, and the collected bile was subjected to reversed-phase HPLC with radioisotope detection. Peaks eluting from HPLC were collected and analyzed using electrospray MS and NMR spectroscopy. HPLC analysis indicated numerous metabolites in both sexes, but male rats excreted greater amounts of glutathione and glucuronide conjugates than females. Electrospray MS and NMR spectra of HPLC fractions revealed that the most prominent metabolite found in bile of both sexes was a glutathione conjugate of an imine metabolite of a 4'-nitroso-DAPM. Seven other metabolites were identified, including acetylated, cysteinyl-glycine, glutamyl-cysteine, glycine, and glucuronide conjugates. While our prior studies demonstrated increased covalent binding of DAPM in the liver and bile of female compared to male rats, in these studies, SDS-PAGE with autoradiography revealed 4-5 radiolabeled protein bands in the bile of rats treated with [{sup 14}C]-DAPM. In addition, these bands were much more prominent in female than in male rats. These studies thus suggest that a plausible mechanism for the increased sensitivity of female rats to DAPM toxicity may be decreased conjugation of reactive DAPM metabolites, leading to greater levels of protein adduct formation.

Chen, Kan; Cole, Richard B. [Department of Chemistry, University of New Orleans, New Orleans, LA (United States); Santa Cruz, Vicente [Department of Pathology, University of Texas Medical Branch, Galveston, TX (United States); Blakeney, Ernest W. [Department of Chemistry, Centenary College, Shreveport, LA (United States); Kanz, Mary F. [Department of Pathology, University of Texas Medical Branch, Galveston, TX (United States); Dugas, Tammy R. [Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center-Shreveport, 1501 Kings Highway, Shreveport, LA 71130 (United States)], E-mail: tdugas@lsuhsc.edu

2008-10-15

272

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

273

Characterization of diabetic neuropathy in the Zucker diabetic Sprague-Dawley rat: a new animal model for type 2 diabetes.  

PubMed

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

274

Assessment of Morphological and Functional Changes in Organs of Rats after Intramuscular Introduction of Iron Nanoparticles and Their Agglomerates  

PubMed Central

The research was performed on male Wistar rats based on assumptions that new microelement preparations containing metal nanoparticles and their agglomerates had potential. Morphological and functional changes in tissues in the injection site and dynamics of chemical element metabolism (25 indicators) in body were assessed after repeated intramuscular injections (total, 7) with preparation containing agglomerate of iron nanoparticles. As a result, iron depot was formed in myosymplasts of injection sites. The quantity of muscle fibers having positive Perls' stain increased with increasing number of injections. However, the concentration of the most chemical elements and iron significantly decreased in the whole skeletal muscle system (injection sites are not included). Consequently, it increased up to the control level after the sixth and the seventh injections. Among the studied organs (liver, kidneys, and spleen), Caspase-3 expression was revealed only in spleen. The expression had a direct dependence on the number of injections. Processes of iron elimination from preparation containing nanoparticles and their agglomerates had different intensity. PMID:25789310

Sizova, Elena; Miroshnikov, Sergey; Yausheva, Elena; Polyakova, Valentina

2015-01-01

275

Sleep deprivation induces differential morphological changes in the hippocampus and prefrontal cortex in young and old rats.  

PubMed

Sleep is a fundamental state necessary for maintenance of physical and neurological homeostasis throughout life. Several studies regarding the functions of sleep have been focused on effects of sleep deprivation on synaptic plasticity at a molecular and electrophysiological level, and only a few studies have studied sleep function from a structural perspective. Moreover, during normal aging, sleep architecture displays some changes that could affect normal development in the elderly. In this study, using a Golgi-Cox staining followed by Sholl analysis, we evaluate the effects of 24 h of total sleep deprivation on neuronal morphology of pyramidal neurons from Layer III of the prefrontal cortex (PFC) and the dorsal hippocampal CA1 region from male Wistar rats at two different ages (3 and 22 months). We found no differences in total dendritic length and branching length in both analyzed regions after sleep deprivation. Spine density was reduced in the CA1 of young-adults, and interestingly, sleep deprivation increased spine density in PFC of aged animals. Taken together, our results show that 24 h of total sleep deprivation have different effects on synaptic plasticity and could play a beneficial role in cognition during aging. PMID:25179486

Acosta-Peña, Eva; Camacho-Abrego, Israel; Melgarejo-Gutiérrez, Montserrat; Flores, Gonzalo; Drucker-Colín, René; García-García, Fabio

2015-01-01

276

Defensive-like behaviors induced by ultrasound: further pharmacological characterization in Lister-hooded rats  

Microsoft Academic Search

Rationale  In rats, dorsal periaqueductal gray (dPAG) stimulation elicits escape behavior that is thought to be related to fear and panic.\\u000a A noninvasive technique—exposure to ultrasound—has been reported to stimulate the dPAG and induce escape followed by freezing\\u000a in Lister-hooded (LH) rats.\\u000a \\u000a \\u000a \\u000a Objective  Further characterize pharmacologically the ultrasound-induced defensive behaviors test with anxiolytics acting via different\\u000a mechanisms.\\u000a \\u000a \\u000a \\u000a Materials and methods  LH rats, treated

Laurent B. Nicolas; Steffen Klein; Eric P. Prinssen

2007-01-01

277

Use of simple sequence length polymorphisms for genetic characterization of rat inbred strains.  

PubMed

Genetic monitoring is an essential component of colony management and for the rat has been accomplished primarily by using immunological and biochemical markers. Here, we report that simple sequence length polymorphisms (SSLPs) are a faster and more economical way of monitoring inbred strains of rats. We characterized 61 inbred strains of rats, using primer pairs for 37 SSLPs. Each of these loci appeared to be highly polymorphic, with the number of alleles per locus ranging between 3 and 14 and, as a result, all the 61 inbred strains tested in this study could be provided with a unique strain profile. These strain profiles are also used for estimating the degree of similarity between strains. This information may provide the rationale in selecting strains for genetic crosses or for other specific purposes. PMID:8535065

Otsen, M; Den Bieman, M; Winer, E S; Jacob, H J; Szpirer, J; Szpirer, C; Bender, K; Van Zutphen, L F

1995-09-01

278

Photochemically induced cystic lesion in the rat spinal cord. I. Behavioral and morphological analysis  

SciTech Connect

The present study describes the production of a spinal cord lesion which is initiated by vascular occlusion resulting from the interaction between the photosensitizing dye erythrosin B and an argon laser beam. The lesion has characteristics similar to those of the central cavity thought to lead to the production of post-traumatic syringomyelia (PTS) in humans. The present study examines the behavioral and morphological characteristics of this injury over a 28-day period. Histological analysis revealed a cavity extending from the dorsal horns to lamina VIII, with some lateral and ventral pathways being spared. The cavity volume reached a maximum 7 days after lesion induction. Behavioral changes were assessed using six different tests of motor and reflex function (motor function, climbing, waterbath, inclined plane, withdrawal to pain, and withdrawal to extension). Lesioned animals exhibited flaccid paralysis for 3-5 days, which resolved afterward. The photochemically induced cavity should provide a reproducible model for examining the effects of cystic spinal cord injury on locomotor and reflex function.

Cameron, T.; Prado, R.; Watson, B.D.; Gonzalez-Carvajal, M.; Holets, V.R. (Univ. of Miami, FL (USA))

1990-08-01

279

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. PMID:25186035

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

2015-01-01

280

Guanine deaminase inhibitor from rat liver. Isolation and characterization  

PubMed Central

1. An inhibitor of cytoplasmic guanine deaminase of rat liver was isolated from liver `heavy mitochondrial' fraction after freezing and thawing and treatment with Triton X-100. 2. Submitochondrial fractionation revealed that the inhibitor was localized in the outer-membrane fraction. 3. The method of purification of inhibitor, involving precipitation with (NH4)2SO4 and chromatography on DEAE-cellulose, its precipitability by trichloroacetic acid and the pattern of absorption in the u.v. indicated that the inhibitor was a protein. In confirmation, tryptic digestion of the isolated material resulted in destruction of the inhibitor activity. The inhibitor was stable to acid, but labile to heat. 4. The isolated inhibitor required phosphatidylcholine (lecithin) for activity. Phosphatidylcholine also partially protected the inhibitor against heat inactivation. 5. When detergent treatment was omitted, the inhibitor activity of frozen mitochondria was precipitated by (NH4)2SO4 in a fully active form without supplementation with phosphatidylcholine, indicating that Triton X-100 ruptured the linkage between inhibitor and lipid. 6. A reconstituted sample of inhibitor–phosphatidylcholine complex was precipitated in a fully active form by dialysis against 2-mercaptoethanol, but treatment of the precipitate with NaCl yielded an extract which was inactive unless supplemented with fresh phosphatidylcholine. 7. We interpret the results as evidence that the inhibitor was present in vivo as a lipoprotein and that once the complex was dissociated by the action of detergent and the protein precipitated, there was an absolute need for exogenous phosphatidylcholine for its activity. The manner in which inhibitor associated with the outer membrane of rat liver mitochondria might regulate the activity of the enzyme in the supernatant has been suggested. PMID:4821397

Ali, Shahid; Sitaramayya, A.; Kumar, K. Sree; Krishnan, Padmanabhan S.

1974-01-01

281

Purification and characterization of rat liver nuclear thyroid hormone receptors  

SciTech Connect

Nuclear thyroid hormone receptor hormone receptor was purified to 904 pmol of L-3,5,3'-triiodothyronine (T3) binding capacity per mg of protein with 2.5-5.2% recovery. Assuming that one T3 molecule binds to the 49,000-Da unit of the receptor, the authors reproducibly obtained 6.4-14.7 ..mu..g of receptor protein with 4.2-4.9% purity from 4-5 kg of rat liver. Elution of receptor from the heparin-Sepharose column was performed using 10 mM pyridoxal 5'-phosphate. This effect was specific for pyridoxal 5'-phosphate, since related compounds were not effective. Purified receptor bound T3 with high affinity, and the order of affinity of iodothyronine analogues to purified receptor was identical to that observed with crude receptor preparations. Purified receptor had a sedimentation coefficient of 3.4 S, Stokes radius of 34 A, and calculated molecular mass of 49,000. Among several bands identified by silver staining after electrophoresis in NaDodSO/sub 4//polyacrylamide gels, one 49,000-Da protein showed photoaffinity labeling with (/sup 125/I)thyroxine that was displaceable with excess unlabeled T3. The tryptic fragment and endogenous proteinase-digested fragment of the affinity-labeled receptor showed saturable binding in 27,000-Da and 36,000-Da peptides, respectively. These molecular masses are in agreement with estimates from gel filtration and gradient sedimentation, indicating that affinity labeling occurred at the hormone binding domain of nuclear thyroid hormone receptor. This procedure reproducibly provides classical native rat liver T3 nuclear receptor in useful quantity and purity and of the highest specific activity so far reported.

Ichikawa, K.; DeGroot, L.J.

1987-05-01

282

Effect of PACAP treatment on kidney morphology and cytokine expression in rat diabetic nephropathy.  

PubMed

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide, exerting diverse effects. One of its frequently examined functions is cell protection, which is achieved mainly via inhibiting apoptotic, inflammatory and oxidative processes. All its three receptors (PAC1, VPAC1, VPAC2) are expressed in the kidney and PACAP has been shown to have protective effects against different renal pathologies. Diabetic nephropathy is the leading cause of end stage renal disease. The aim of the present study was to investigate the possible ameliorative effect of PACAP in streptozotocin-induced diabetic nephropathy and to evaluate its anti-inflammatory effect in this model. Diabetes was induced by a single intravenous injection of streptozotocin (65 mg/kg) in male Wistar rats. PACAP-treated animals were administered ip. 20 ?g PACAP every second day, while untreated animals were given vehicle. Kidneys were removed after 8-weeks survival. Besides the complex histological analysis (glomerular PAS positive area/glomerulus area, tubular damage, arteriolar hyalinosis), expression of several cytokines was evaluated by cytokine array and Luminex assay. Histological analysis revealed severe diabetic changes in kidneys of control diabetic animals (glomerular PAS-positive area expansion, tubular damage, Armanni-Ebstein phenomenon). PACAP treatment significantly diminished the damage. Diabetic kidneys showed significant cytokine activation compared to their healthy controls. PACAP was effective in downregulation of several cytokines including CINC-1, TIMP-1, LIX, MIG, s-ICAM. To conclude, PACAP is effective in ameliorating diabetic nephropathy at least partly through its well-known anti-inflammatory effect. These results raise the opportunity for the use of PACAP as a possible therapeutic or preventive method in treating the complications of diabetes. PMID:23416022

Banki, E; Degrell, P; Kiss, P; Kovacs, K; Kemeny, A; Csanaky, K; Duh, A; Nagy, D; Toth, G; Tamas, A; Reglodi, D

2013-04-01

283

Identification and partial characterization of a prolactin-like hormone produced by rat decidual tissue.  

PubMed Central

Previous studies have strongly, but indirectly, suggested that rat decidual tissue produces a prolactin-like hormone, decidual luteotropin, which markedly affects luteal cell function. However, it was also found that extracts of decidual tissue do not cross-react with antisera to either rat or ovine prolactin (PRL). The purpose of this study was to determine whether the decidual tissue contains a substance that binds to PRL receptors in rat luteal membranes and, if so, to identify, quantitate, and characterize this molecule with the use of an ovarian radioreceptor assay. Decidual tissue was induced in day 5 pseudopregnant rats by scratching the antimesometrial wall of the uterus; it was collected on day 9 and homogenized and extracted. Decidual tissue extracts bound specifically to ovarian PRL receptors. Graded dilutions of the extracts yielded curves that were parallel to the ovine PRL standard, indicating that decidual luteotropin competes for the same receptor sites on rat luteal membranes. To determine the levels of decidual luteotropin throughout pseudopregnancy, decidual tissue was obtained on each day between days 6-12. The PRL-like activity was detectable in decidual tissue as early as day 6, reached a maximum on day 9, and declined thereafter. The elution profile obtained from gel filtration of a day 9 decidual tissue extract displayed a major component of decidual luteotropin eluting at a Ve/Vo ratio of approximately equal to 2.0. Column chromatography indicated that decidual luteotropin corresponds to a protein with a molecular weight of 23,500. The hormone was heat labile, digestible by trypsin, and appears to contain disulfide linkages. In summary, this study reports the identification, quantitation, and partial characterization of a PRL-like hormone produced by the decidual tissue of the rat. Images PMID:2982145

Jayatilak, P G; Glaser, L A; Basuray, R; Kelly, P A; Gibori, G

1985-01-01

284

Quantitative characterization of the influence of the nanoscale morphology of nanostructured surfaces on bacterial adhesion and biofilm formation.  

PubMed

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; Podestà, Alessandro; Lenardi, Cristina; Gade, Wasudev Namdev; Milani, Paolo

2011-01-01

285

Construction and Characterization of a 10Genome Equivalent Yeast Artificial Chromosome Library for the Laboratory Rat, Rattus norvegicus  

Microsoft Academic Search

Increasing attention has been focused in recent years on the rat as a model organism for genetic studies, in particular for the investigation of complex traits, but progress has been limited by the lack of availability of large-insert genomic libraries. Here, we report the construction and characterization of an arrayed yeast artificial chromosome (YAC) library for the rat genome containing

Li Cai; Leonard C. Schalkwyk; Andreina Schoeberlein-Stehli; Robert Y. L. Zee; Avrial Smith; Thomas Haaf; Michel Georges; Hans Lehrach; Klaus Lindpaintner

1997-01-01

286

Morphological and chemical characterization of mineral concretions in the freshwater bivalve Anodonta cygnea (Unionidae).  

PubMed

The freshwater mussel Anodonta cygnea is commonly used as a model organism for biomineralization studies, its peculiar morphofunctional properties also make it an excellent environmental biomonitor. The first detailed on the calcareous concretions from gill and mantle tissue, as well as fluids of the freshwater bivalve A. cygnea, supported by histological, scanning, spectrometry, and spectroscopy analyses. Through these analyses, the morphology, structure, and chemical characterization of these biomineral concretions were accomplished. The concretions represent a high percentage of the dry weight of these organisms. In gill tissue, it can reach up to 50% of dry weight prior to reproductive maturity. Analysis of elemental composition of the tissue concretions showed the presence of calcium and phosphate, as main components, associated with other residual elements like iron, manganese, magnesium, and zinc. Concretions are arranged in concentric alternated layers of organic and inorganic matrix. The shape and size of the concretions vary substantially, from very small, less than 1 ?m diameter with very regular round structure, found mainly in the mantle tissue, to more than 50 ?m length with irregular globular clusters, found predominantly in the gills. The microstructural organization is of a hydroxyapatite polymorphism in the mantle, in contrast to the gills, which exhibit irregular structure and carbonated hydroxyapatite polymorphism. These differences are supported by higher contents of dinitrogen pentoxide, magnesium, and iron in the mantle concretions, but higher contents of manganese and zinc in the gills. Furthermore, the results indicate that the mineral concretion formation in A. cygnea is a hemocytes reaction to particle or toxic invasions. A second relevant role, concerns the close involvement of these microspherules on the adult and larval shell calcification. PMID:25242687

Hinzmann, Mariana F; Lopes-Lima, Manuel; Bobos, Iulius; Ferreira, Jorge; Domingues, Bernardo; Machado, Jorge

2015-01-01

287

Isolation and Characterization of Rat Pituitary Endothelial Cells  

Microsoft Academic Search

Most previous studies that determined the effect of estradiol on angiogenesis used endothelial cells from nonpituitary sources. Because pituitary tumor tissue receives its blood supply via portal and arterial circulation, it is important to use pituitary-derived endothelial cells in studying pituitary angiogenesis. We have developed a magnetic separation technique to isolate endothelial cells from pituitary tissues and have characterized these

Kirti Chaturvedi; Dipak K. Sarkar

2006-01-01

288

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

289

Characterization of Time-Course Morphological Features for Efficient Prediction of Osteogenic Potential in Human Mesenchymal Stem Cells  

PubMed Central

Human bone marrow mesenchymal stem cells (hBMSCs) represents one of the most frequently applied cell sources for clinical bone regeneration. To achieve the greatest therapeutic effect, it is crucial to evaluate the osteogenic differentiation potential of the stem cells during their culture before the implantation. However, the practical evaluation of stem cell osteogenicity has been limited to invasive biological marker analysis that only enables assaying a single end-point. To innovate around invasive quality assessments in clinical cell therapy, we previously explored and demonstrated the positive predictive value of using time-course images taken during differentiation culture for hBMSC bone differentiation potential. This initial method establishes proof of concept for a morphology-based cell evaluation approach, but reveals a practical limitation when considering the need to handle large amounts of image data. In this report, we aimed to scale-down our proposed method into a more practical, efficient modeling scheme that can be more broadly implemented by physicians on the frontiers of clinical cell therapy. We investigated which morphological features are critical during the osteogenic differentiation period to assure the performance of prediction models with reduced burden on image acquisition. To our knowledge, this is the first detailed characterization that describes both the critical observation period and the critical number of time-points needed for morphological features to adequately model osteogenic potential. Our results revealed three important observations: (i) the morphological features from the first 3 days of differentiation are sufficiently informative to predict bone differentiation potential, both activities of alkaline phosphatase and calcium deposition, after 3 weeks of continuous culture; (ii) intervals of 48?h are sufficient for measuring critical morphological features; and (iii) morphological features are most accurately predictive when early morphological features from the first 3 days of differentiation are combined with later features (after 10 days of differentiation). Biotechnol. Bioeng. 2014;111: 1430–1439. PMID:24420699

Matsuoka, Fumiko; Takeuchi, Ichiro; Agata, Hideki; Kagami, Hideaki; Shiono, Hirofumi; Kiyota, Yasujiro; Honda, Hiroyuki; Kato, Ryuji

2014-01-01

290

Characterization of time-course morphological features for efficient prediction of osteogenic potential in human mesenchymal stem cells.  

PubMed

Human bone marrow mesenchymal stem cells (hBMSCs) represents one of the most frequently applied cell sources for clinical bone regeneration. To achieve the greatest therapeutic effect, it is crucial to evaluate the osteogenic differentiation potential of the stem cells during their culture before the implantation. However, the practical evaluation of stem cell osteogenicity has been limited to invasive biological marker analysis that only enables assaying a single end-point. To innovate around invasive quality assessments in clinical cell therapy, we previously explored and demonstrated the positive predictive value of using time-course images taken during differentiation culture for hBMSC bone differentiation potential. This initial method establishes proof of concept for a morphology-based cell evaluation approach, but reveals a practical limitation when considering the need to handle large amounts of image data. In this report, we aimed to scale-down our proposed method into a more practical, efficient modeling scheme that can be more broadly implemented by physicians on the frontiers of clinical cell therapy. We investigated which morphological features are critical during the osteogenic differentiation period to assure the performance of prediction models with reduced burden on image acquisition. To our knowledge, this is the first detailed characterization that describes both the critical observation period and the critical number of time-points needed for morphological features to adequately model osteogenic potential. Our results revealed three important observations: (i) the morphological features from the first 3 days of differentiation are sufficiently informative to predict bone differentiation potential, both activities of alkaline phosphatase and calcium deposition, after 3 weeks of continuous culture; (ii) intervals of 48 h are sufficient for measuring critical morphological features; and (iii) morphological features are most accurately predictive when early morphological features from the first 3 days of differentiation are combined with later features (after 10 days of differentiation). PMID:24420699

Matsuoka, Fumiko; Takeuchi, Ichiro; Agata, Hideki; Kagami, Hideaki; Shiono, Hirofumi; Kiyota, Yasujiro; Honda, Hiroyuki; Kato, Ryuji

2014-07-01

291

Characterization of uronic-acid-rich inhibitor of calcium oxalate crystallization isolated from rat urine  

Microsoft Academic Search

Human urine contains several macromolecules which inhibit calcium oxalate crystallization. Uronic-acid-rich protein (UAP), a glycoprotein with a molecular weight of approximately 35 kDa, is one such inhibitor. Here we report the characterization of UAP extracted from rat urine using three chromatographic steps including diethylaminoethanol (DEAE)-Sephacel, Sephacryl S-300 and Mono Q column and compare it with human UAP. The molecular weight

F. Atmani; S. R. Khan

1995-01-01

292

Intrinsic Connectivity of the Rat Subiculum: I. Dendritic Morphology and Patterns of Axonal Arborization by Pyramidal Neurons  

PubMed Central

The dendritic and axonal morphology of rat subicular neurons was studied in single cells labeled with Neurobiotin. Electrophysiological classification of cells as intrinsic burst firing or regular spiking neurons was correlated with morphologic patterns and cell locations. Every cell had dendritic branches that reached the outer molecular layer, with most cells having branches that reached the hippocampal fissure. All but two pyramidal cells had axon collaterals that entered the deep white matter (alveus). Branching patterns of apical dendrites varied as a function of the cell’s soma location along the fissure–alveus axis of the cell layer. The first major dendritic branch point for most cells occurred at the superficial edge of the cell layer giving deep cells long primary apical dendrites and superficial cells short or absent primary apical dendrites. In contrast, basal dendritic arbors were similar across cells regardless of cell position. Apical and basal dendrites of all cells had numerous spines. Superficial and deep cells also differed in axonal collateralization. Deep cells (mostly intrinsically bursting [IB] class) had one or more ascending axon collaterals that typically remained within the region circumscribed by their apical dendrites. Superficial cells (mostly regular spiking [RS] class) tended to have axon collaterals that reached longer distances in the cell layer. Numerous varicosities and axonal extensions were present on axon collaterals in the cell layer and in the apical dendritic region, suggesting intrinsic connectivity. Axonal varicosities and extensions were found on axons that entered presubiculum, entorhinal cortex or CA1, supporting the notion that these were projection cells. Local collaterals were distinctly thinner than collaterals that would leave the subiculum, suggesting little or no myelin on local collaterals and some myelin on efferent fibers. We conclude that both IB and RS classes of subicular principal cells make synaptic contacts in and apical to the cell layer. Based on the patterns of axonal arborization, we suggest that subiculum has at least a crude columnar and laminar architecture, with ascending collaterals of deep cells forming columns and broader axonal arbors of superficial cells serving to distribute activity across multiple columns. PMID:11406828

HARRIS, ELANA; WITTER, MENNO P.; WEINSTEIN, GILA; STEWART, MARK

2006-01-01

293

Somatostatin inhibition of GnRH neuronal activity and the morphological relationship between GnRH and somatostatin neurons in rats.  

PubMed

In rodents, GnRH neurons are diffusely distributed from the medial septum through to the medial preoptic area and control gonadal functions through the pituitary. The activity of GnRH neurons is regulated by a variety of bioactive substances, including the inhibitory peptide somatostatin. In the present study, we focused on somatostatin because intracerebroventricular injection of somatostatin inhibits the LH surge in rats and reduces LH secretion in ewes. Somatostatin also decreases GnRH release from rat hypothalamic slices. In mice, somatostatin is also thought to suppress GnRH neuronal activity through contact on the soma of GnRH neurons. However, similar data are missing in rats. Moreover, rat GnRH neurons receive only a few synaptic inputs. In this study, we assessed the morphological relationship between GnRH and somatostatin neurons. Confocal microscopy on the sections from the medial septum through medial preoptic area revealed about 35 close contacts per rat between the GnRH and somatostatin neuronal fibers in the organum vasculosum of the lamina terminalis region. No contact of somatostatin fibers on the GnRH neuronal somata was observed. Multicell RT-PCR for somatostatin receptor mRNA in rat GnRH neurons was also performed, which revealed moderate expression of somatostatin receptor subtypes 1-5. In addition, patch clamp experiments were carried out in acute slice preparations. Somatostatin suppressed neuronal firing in cells recorded in a cell-attached configuration and also induced whole-cell outward currents in GnRH neurons. These findings suggest that somatostatin directly inhibits the activity of rat GnRH neurons through volume transmission in the organum vasculosum of the lamina terminalis region. PMID:22147011

Koyama, Makiko; Yin, Chengzhu; Ishii, Hirotaka; Sakuma, Yasuo; Kato, Masakatsu

2012-02-01

294

Morphological changes in the triads and sarcoplasmic reticulum of rat slow and fast muscle fibres following denervation and immobilization.  

PubMed

We observed the morphological features of the membrane systems (sarcoplasmic reticulum, transverse tubules and triads) involved with the excitation-contraction coupling in rat soleus and extensor digitorum longus muscle following two disuse protocols: denervation and immobilization. The immobilized positions were: maximum dorsal flexor (soleus were stretched and extensor digitorum longus were shortened), maximum plantar flexor (soleus were shortened and extensor digitorum longus were stretched), and midway between the dorsal flexor and plantar flexor. The arrangement of the membrane systems was disordered following both disuse conditions. Increases in transverse tubule network were apparent; there were clearly more triads than in normal fibres, and pentadic and heptadic structures (i.e., a close approximation of two or three transverse tubule elements with three or four elements of terminal cisternae of sarcoplasmic reticulum) were frequently appeared following both denervation and immobilization. The most notable difference between the influence of denervation and immobilization on the membrane systems is the time at which the pentads and heptads appeared. They appeared much earlier (1 week after denervation) in denervated than in immobilized (3 or 4 weeks after immobilization) muscle fibres. On the other hand, the frequency of pentads and heptads is clearly related to the fibre type (significantly higher in extensor digitorum longus) and to extent of atrophy. The different influences of immobilization in each leg position suggest that disuse, but with neurotrophic factor(s), influences on the membrane systems were affected by sarcomere length, and the neurotrophic factor(s) and muscle activity were not always necessary to form new membrane systems in disuse skeletal muscle fibres. PMID:8884595

Takekura, H; Kasuga, N; Kitada, K; Yoshioka, T

1996-08-01

295

Characterization of the Morphology of Faceted Particles by Transmission Electron Microscopy  

E-print Network

with morphological models. The 2TR holder has three degrees of freedom theoretically allowing the TEM operator holder was used to manipulate the particle. Using this holder, it was possible to align the c axis

Moeck, Peter

296

Characterization of new surface morphologies in a hydrogen-bonded multilayer system  

E-print Network

This work presents an analysis of surface morphology changes in poly(acrylic acid)/polyacrylamide (PAA/PAAm) hydrogen-bonded multilayers. These changes were induced by immersion of the films in aqueous solutions of ...

Kunz, Allison (Allison L.)

2008-01-01

297

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

298

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

299

Immunocytochemical characterization of catecholaminergic neurons in the rat striatum following dopamine-depleting lesions.  

PubMed

It is possible either permanently or transiently to deplete the rat striatum of dopamine. Following such depletions, striatal neurons immunoreactive for tyrosine hydroxylase (TH), aromatic L-amino acid decarboxylase (AADC) or dopamine appear. The presence of dopamine-producing neurons in the striatum has relevance for the treatment of Parkinson's disease, but whether these catecholaminergic phenotypes all produce dopamine is unclear. In the present study we establish that after unilateral 6-hydroxydopamine lesions or methamphetamine administration, striatal TH-immunoreactive neurons differ in size, morphology and location from those that are immunopositive for AADC or dopamine. The TH-positive cells which were localized either to ventral parts of the striatum or to the central and dorsal areas of the caudate-putamen generally have the morphological features of projection neurons, whereas those containing AADC or dopamine were confined to subcallosal positions in the dorsal medial quadrant of the caudate-putamen and resemble small, local-circuit neurons. The fact that AADC-immunoreactive neurons overlap in size, morphology and location with the cells that produce dopamine suggests strongly that this population is dopaminergic. However, the simultaneous appearance of neurons that contain the TH enzyme but clearly do not make dopamine raises questions about the functional role of these cells and the cellular mechanisms responsible for their induction following striatal dopamine loss. PMID:10564366

Meredith, G E; Farrell, T; Kellaghan, P; Tan, Y; Zahm, D S; Totterdell, S

1999-10-01

300

Electrophysiological and morphological characterization of neuronal microcircuits in acute brain slices using paired patch-clamp recordings.  

PubMed

The combination of patch clamp recordings from two (or more) synaptically coupled neurons (paired recordings) in acute brain slice preparations with simultaneous intracellular biocytin filling allows a correlated analysis of their structural and functional properties. With this method it is possible to identify and characterize both pre- and postsynaptic neurons by their morphology and electrophysiological response pattern. Paired recordings allow studying the connectivity patterns between these neurons as well as the properties of both chemical and electrical synaptic transmission. Here, we give a step-by-step description of the procedures required to obtain reliable paired recordings together with an optimal recovery of the neuron morphology. We will describe how pairs of neurons connected via chemical synapses or gap junctions are identified in brain slice preparations. We will outline how neurons are reconstructed to obtain their 3D morphology of the dendritic and axonal domain and how synaptic contacts are identified and localized. We will also discuss the caveats and limitations of the paired recording technique, in particular those associated with dendritic and axonal truncations during the preparation of brain slices because these strongly affect connectivity estimates. However, because of the versatility of the paired recording approach it will remain a valuable tool in characterizing different aspects of synaptic transmission at identified neuronal microcircuits in the brain. PMID:25650985

Qi, Guanxiao; Radnikow, Gabriele; Feldmeyer, Dirk

2015-01-01

301

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

PubMed

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

302

The effects of different sugars on motility, morphology and DNA damage during the liquid storage of rat epididymal sperm at 4°C.  

PubMed

This study evaluated the protective effects of supplementation with three different sugars on the motility, morphology and DNA integrity of rat epididymal sperm chilled and stored at 4°C Epididymides were obtained from each donor. Rat epididymal sperm was diluted in Ham's F10 plus raffinose, Ham's F10 plus trehalose, Ham's F10 plus fructose, and Ham's F10 medium for control purposes. Thereafter, the extended sperm were chilled and stored in liquid form at 4°C. Sperm motility, morphological abnormalities and DNA damage were determined at 0 and 12h after chilling. No significant difference was observed in any of the parameters evaluated at 0h, before storage (P>0.05). After 12h of storage, all sugar additives led to statistically higher motility, normal sperm morphology and DNA integrity in comparison to the control group. Raffinose gave the best motility percentages (32.86±1.84%) after 12h of storage at 4°C, compared to the other groups (P<0.001). In conclusion, Raffinose, trehalose and fructose provided a better protection of sperm functional parameters against chilling injury, in comparison to the control group. PMID:22634115

Sariözkan, Serpil; Bucak, Mustafa Numan; Canturk, Fazile; Özdamar, Saim; Yay, Arzu; Tuncer, Pürhan Barbaros; Özcan, Servet; Sorgucu, Neslihan; Caner, Yusuf

2012-10-01

303

Myocardial Dysfunction Induced by Food Restriction is Related to Morphological Damage in Normotensive Middle-Aged Rats  

Microsoft Academic Search

Summary  Previous works from our laboratory have revealed that food restriction (FR) promotes discrete myocardial dysfunction in young\\u000a rats. We examined the effects of FR on cardiac function, in vivo and in vitro, and ultrastructural changes in the heart of middle-aged rats. Twelve-month-old Wistar-Kyoto rats were fed a control (C)\\u000a or restricted diet (daily intake reduced to 50% of the control

Mario Mateus Sugizaki; Robson Francisco Carvalho; Flavio Ferrari Aragon; Carlos Roberto Padovani; Katashi Okoshi; Marina Politi Okoshi; Silmeia Garcia Zanati; Maeli Dal Pai-Silva; Ethel Lourenzi Barbosa Novelli; Antonio Carlos Cicogna

2005-01-01

304

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

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

305

Development and characterization of an exposure platform suitable for physico-chemical, morphological and toxicological characterization of printer-emitted particles (PEPs).  

PubMed

An association between laser printer use and emissions of particulate matter (PM), ozone and volatile organic compounds has been reported in recent studies. However, the detailed physico-chemical, morphological and toxicological characterization of these printer-emitted particles (PEPs) and possible incorporation of engineered nanomaterials into toner formulations remain largely unknown. In this study, a printer exposure generation system suitable for the physico-chemical, morphological, and toxicological characterization of PEPs was developed and used to assess the properties of PEPs from the use of commercially available laser printers. The system consists of a glovebox type environmental chamber for uninterrupted printer operation, real-time and time-integrated particle sampling instrumentation for the size fractionation and sampling of PEPs and an exposure chamber for inhalation toxicological studies. Eleven commonly used laser printers were evaluated and ranked based on their PM emission profiles. Results show PM peak emissions are brand independent and varied between 3000 to 1?300?000?particles/cm³, with modal diameters ranging from 49 to 208?nm, with the majority of PEPs in the nanoscale (<100?nm) size. Furthermore, it was shown that PEPs can be affected by certain operational parameters and printing conditions. The release of nanoscale particles from a nano-enabled product (printer toner) raises questions about health implications to users. The presented PEGS platform will help in assessing the toxicological profile of PEPs and the link to the physico-chemical and morphological properties of emitted PM and toner formulations. PMID:24862974

Pirela, Sandra V; Pyrgiotakis, Georgios; Bello, Dhimiter; Thomas, Treye; Castranova, Vincent; Demokritou, Philip

2014-06-01

306

Development and characterization of an exposure platform suitable for physico-chemical, morphological and toxicological characterization of printer-emitted particles (PEPs)  

PubMed Central

An association between laser printer use and emissions of particulate matter (PM), ozone and volatile organic compounds has been reported in recent studies. However, the detailed physico-chemical, morphological and toxicological characterization of these printer-emitted particles (PEPs) and possible incorporation of engineered nanomaterials into toner formulations remain largely unknown. In this study, a printer exposure generation system suitable for the physico-chemical, morphological, and toxicological characterization of PEPs was developed and used to assess the properties of PEPs from the use of commercially available laser printers. The system consists of a glovebox type environmental chamber for uninterrupted printer operation, real-time and time-integrated particle sampling instrumentation for the size fractionation and sampling of PEPs and an exposure chamber for inhalation toxicological studies. Eleven commonly used laser printers were evaluated and ranked based on their PM emission profiles. Results show PM peak emissions are brand independent and varied between 3000 to 1 300 000 particles/cm3, with modal diameters ranging from 49 to 208 nm, with the majority of PEPs in the nanoscale (<100 nm) size. Furthermore, it was shown that PEPs can be affected by certain operational parameters and printing conditions. The release of nanoscale particles from a nano-enabled product (printer toner) raises questions about health implications to users. The presented PEGS platform will help in assessing the toxicological profile of PEPs and the link to the physico-chemical and morphological properties of emitted PM and toner formulations. PMID:24862974

Pirela, Sandra V.; Pyrgiotakis, Georgios; Bello, Dhimiter; Thomas, Treye; Castranova, Vincent; Demokritou, Philip

2015-01-01

307

Solvothermal synthesis and characterization of ceria with solid and hollow spherical and multilayered morphologies  

NASA Astrophysics Data System (ADS)

Ceria powders with different morphologies were synthesized using a facile template-free solvothermal process combined with calcination. The influence of solvothermal temperature and time on the powder was studied. Solid spheres, hollow spheres, and multilayered structures were controlled by adjusting the solvothermal conditions. The possible mechanisms for the formation of the precursors under the solvothermal conditions employed and the evolution of the powder from solid spherical to multilayered structures were discussed. Ethylene glycol played a key role in the morphology evolution of the powder. Cerium catalyzed the Guerbet-like reaction and reacted with ethylene glycol to produce ceria (CeO2), Ce(HCOO)3, and Ce(OH)CO3. The redox-assisted dissolution-recrystallization process significantly contributed to the morphology transformation from solid spheres to multilayered structures. Moreover, the samples synthesized at different temperatures for 24 h possessed excellent adsorption capacities towards the removal of acid orange 7 when compared with commercial ceria.

He, Lei; Li, Junping; Feng, Zhihai; Sun, Dongfeng; Wang, Tingyu; Li, Ruixing; Xu, Yaohui

2014-12-01

308

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

309

Characterization of Differential Cocaine Metabolism in Mouse and Rat through Metabolomics-Guided Metabolite Profiling  

PubMed Central

Rodent animal models have been widely used for studying neurologic and toxicological events associated with cocaine abuse. It is known that the mouse is more susceptible to cocaine-induced hepatotoxicity (CIH) than the rat. However, the causes behind this species-dependent sensitivity to cocaine have not been elucidated. In this study, cocaine metabolism in the mouse and rat was characterized through LC-MS-based metabolomic analysis of urine samples and were further compared through calculating the relative abundance of individual cocaine metabolites. The results showed that the levels of benzoylecgonine, a major cocaine metabolite from ester hydrolysis, were comparable in the urine from the mice and rats treated with the same dose of cocaine. However, the levels of the cocaine metabolites from oxidative metabolism, such as N-hydroxybenzoylnorecgonine and hydroxybenzoylecgonine, differed dramatically between the two species, indicating species-dependent cocaine metabolism. Subsequent structural analysis through accurate mass analysis and LC-MS/MS fragmentation revealed that N-oxidation reactions, including N-demethylation and N-hydroxylation, are preferred metabolic routes in the mouse, while extensive aryl hydroxylation reactions occur in the rat. Through stable isotope tracing and in vitro enzyme reactions, a mouse-specific ?-glucoside of N-hydroxybenzoylnorecgonine and a group of aryl hydroxy glucuronides high in the rat were identified and structurally elucidated. The differences in the in vivo oxidative metabolism of cocaine between the two rodent species were confirmed by the in vitro microsomal incubations. Chemical inhibition of P450 enzymes further revealed that different P450-mediated oxidative reactions in the ecgonine and benzoic acid moieties of cocaine contribute to the species-dependent biotransformation of cocaine. PMID:23034697

Yao, Dan; Shi, Xiaolei; Wang, Lei; Gosnell, Blake A.

2013-01-01

310

Isolation and characterization of Candida albicans morphological mutants derepressed for the formation of filamentous hypha-type structures  

SciTech Connect

Several Candida albicans morphological mutants were obtained by a procedure based on a combined treatment with nitrous acid plus UV irradiation and a double-enrichment step to increase the proportion of mutants growing as long filamentous structures. Altered cell morphogenesis in these mutants correlated with an altered colonial phenotype. Two of these mutants, C. albicans NEL102 and NEL103, were selected and characterized. Mutant blastoconidia initiated budding but eventually gave rise to filamentous hypha-type formations. These filaments were long and septate, and they branched very regularly at positions near septa. Calcofluor white (which is known to bind chitin-rich areas) stained septa, branching zones, and filament tips very intensely, as observed under the fluorescence microscope. Wild-type hybrids were obtained by fusing protoplasts of strain NEL102 with B14, another morphological mutant previously described as being permanently pseudomycelial, indicating that genetic determinants responsible for the two altered phenotypes are different. The mutants characterized in this work seemed to sequentially express the morphogenic characteristics of C. albicans, from blastoconidia to hyphae, in the absence of any inducer. Further characterization of these strains could be relevant to gain understanding of the genetic control of dimorphism in this species.

Gil, C.; Pomes, R.; Nombela, C. (Universidad Complutense, Madrid (Spain))

1990-05-01

311

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 ...

312

Particle Morphology and Density Characterization by Combined Mobility and Aerodynamic Diameter Measurements. Part 1: Theory  

Microsoft Academic Search

Different on-line submicron particle sizing techniques report different “equivalent diameters.” For example, differential mobility analyzers (DMAs) report electrical mobility diameter (dm), while a number of recently developed instruments (such as the Aerodyne aerosol mass spectrometer, or AMS) measure vacuum aerodynamic diameter (dva). Particle density and physical morphology (shape) have important effects on diameter measurements. Here a framework is presented for

Peter F. DeCarlo; Jay G. Slowik; Douglas R. Worsnop; Paul Davidovits; Jose L. Jimenez

2004-01-01

313

MORPHOLOGICAL AND HISTOCHEMICAL CHARACTERIZATION OF THE SEMINIFEROUS EPITHELIAL AND LEYDIG CELLS OF THE TURKEY.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Unlike mammals, there is little fundamental information about spermatogenesis in birds. This study was undertaken to clarify the morphology, histochemistry, and lectin affinity of the seminiferous epithelial cells and Leydig cells in the pre-pubertal (8- to I5-wk old) and adult (40-to 44-wk old) do...

314

Three novel species of Stemphylium from Sinkiang, China: their morphological and molecular characterization  

Technology Transfer Automated Retrieval System (TEKTRAN)

Three new species of Stemphylium were isolated from diseased leaves of Luffa cylindrica, Lycium chinense and Cucumis melo growing in the Sinkiang province of Northwest China. Stemphylium luffae, S. lycii and S. cucumis are described by morphological and molecular phylogenetic analyses. The principal...

315

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

316

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...

317

Intestinal inflammation and activation of sensory nerve pathways: a functional and morphological study in the nematode infected rat  

Microsoft Academic Search

BACKGROUNDIn the rat, gastric distension elicits an intensity dependent pseudoaffective bradycardia mediated via capsaicin sensitive afferent and cholinergic efferent vagal pathways. Inflammation alters visceral perception although the mediators responsible have not been identified. In the nematode infected rat, there is a substantial increase in neuronal substance P (SP) content of the gut.AIMSTo examine the effects of inflammation on perception of

R De Giorgio; G Barbara; P Blennerhassett; L Wang; V Stanghellini; R Corinaldesi; S M Collins; G Tougas

2001-01-01

318

Morphological and functional changes due to drug-induced lysosomal storage of sulphated glycosaminoglycans in the rat retina  

Microsoft Academic Search

A series of dicationic amphiphilic drugs, most of them immunomodulatory agents, are known to induce generalised lysosomal storage of sulphated glycosaminoglycans (GAGs) in rats and in cultured cells of several species including man. The present study deals with the cytological effects of two experimental immunomodulatory acridine derivatives upon the retina of rats. The animals were treated orally with compound CL-90.100

Timm Bredehorn; Matthias Clausen; Gernot Duncker; Renate Lüllmann-Rauch

2001-01-01

319

Surfactant-assisted solvo- or hydrothermal fabrication and characterization of high-surface-area porous calcium carbonate with multiple morphologies  

Microsoft Academic Search

Hexagonally crystallized CaCO3 materials with flower-like, belt-like, network-like, coralloid, and hexagonal and rectangular parallelepiped morphologies were selectively fabricated using the surfactant (cetyltrimethylammonium bromide, sodium dodecyl sulfate, poly(N-vinyl-2-pyrrolidone or poly(ethylene glycol) (PEG)) mediated solvo- or hydrothermal strategy with CaO powders as Ca source in an oleic acid (OA)\\/ethanol, OA\\/ethylene glycol or water solvent, respectively. The as-obtained materials were characterized by means

Zhenxuan Zhao; Lei Zhang; Hongxing Dai; Yucheng Du; Xue Meng; Ruzhen Zhang; Yuxi Liu; Jiguang Deng

2011-01-01

320

An inverse light scattering technique for morphological characterization of irregular particles based on the Gaussian-random-sphere model.  

PubMed

The Gaussian-random-sphere model is employed for morphological characterization of nonspherical, irregular particles using an inverse light scattering technique. The synthetic measurement data consist of reduced scattering spectra caused by an aggregate of irregular particles randomly oriented in turbid media and are generated using the discrete dipole approximation. The proposed method simultaneously retrieves the concentration and shape parameters of particles using the data collected at multiple wavelengths. The performance of the inverse algorithm is tested using noise-corrupted data, in which up to 50% noise may be added to the observed scattering spectra. PMID:22673444

Hajihashemi, M Reza; Jiang, Huabei

2012-06-01

321

Qualitatively different effect of repeated stress during adolescence on principal neuron morphology across lateral and basal nuclei of the rat amygdala.  

PubMed

Repeated stress can elicit symptoms of depression and anxiety. The amygdala is a significant contributor to the expression of emotion and the basolateral amygdala (BLA) is a major target for the effects of stress on emotion. The adolescent time period may be particularly susceptible to the effects of stress on emotion. While repeated stress has been demonstrated to modify the morphology of BLA neurons in adult rats, little is known about its effects on BLA neurons during adolescence. This study tests the effects of repeated stress during adolescence on BLA neuronal morphology, and whether these are similar to the effects of stress during adulthood. The BLA includes the basal (BA) and lateral (LAT) nuclei, which are differentially responsive to stress in adults. Therefore, effects of stress during adolescence were compared between the BA and LAT nuclei. Morphological features of reconstructed BLA neurons were examined using Golgi-Cox-stained tissue from control or repeated restraint stress-exposed rats. We found subtle dendritic growth coupled with loss of spines after repeated stress during adolescence. The magnitude and dendritic location of these differences varied between the BA and LAT nuclei in strong contrast to the stress-induced increases in spine number seen in adults. These results demonstrate that repeated stress during adolescence has markedly different effects on BLA neuronal morphology, and the extent of these changes is BLA nucleus-dependent. Moreover, altered neuroanatomy was associated with age-dependent effects of repeated stress on generalization of fear, and may point to the necessity for different approaches to target stress-induced changes in adolescents. PMID:25701125

Padival, M A; Blume, S R; Vantrease, J E; Rosenkranz, J A

2015-04-16

322

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

323

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

PubMed Central

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; Tong, Yi-Ping

2013-01-01

324

Characterization of Corneal Keratocyte Morphology and Mechanical Activity within 3-D Collagen Matrices  

PubMed Central

The purpose of this study was to assess quantitatively the differences in morphology, cytoskeletal organization and mechanical behavior between quiescent corneal keratocytes and activated fibroblasts in a 3-D culture model. Primary cultures of rabbit corneal keratocytes and fibroblasts were plated inside type I collagen matrices in serum-freemedia or 10% FBS, and allowed to spread for 1–5 days. Following F-actin labeling using phalloidin, and immunolabeling of tubulin, ?-smooth muscle actin or connexin 43, fluorescent and reflected light (for collagen fibrils) 3-D optical section images were acquired using laser confocal microscopy. In other experiments, dynamic imaging was performed using differential interference contrast microscopy, and finite element modeling was used to map ECM deformations. Corneal keratocytes developed a stellate morphology with numerous cell processes that ran a tortuous path between and along collagen fibrils without any apparent impact on their alignment. Fibroblasts on the other hand, had a more bipolar morphology with pseudopodial processes (p ? 0.001). Time lapse imaging of keratocytes revealed occasional extension and retraction of dendritic processes with only transient displacements of collagen fibrils, whereas fibroblasts exerted stronger myosin II-dependent contractile forces (P < 0.01), causing increased compaction and alignment of collagen at the ends of the pseudopodia (P < 0.001). At high cell density, both keratocytes and fibroblasts appeared to form a 3-D network connected via gap junctions. Overall, this experimental model provides a unique platform for quantitative investigation of the morphological, cytoskeletal and contractile behavior of corneal keratocytes (i.e. their mechanical phenotype) in a 3-D microenvironment. PMID:20025872

Lakshman, Neema; Kim, Areum; Petroll, W. Matthew

2010-01-01

325

Molecular, phytochemical and morphological characterization of the liverwort genus Radula in Portugal (mainland, Madeira, Azores)  

Microsoft Academic Search

Relationships of the eight species of the liverwort genus Radula occurring in Portugal (mainland, the Madeira and Azores archipelagos), including the Macaronesian endemics R. jonesii and R. wichurae, were evaluated based on molecular, phytochemical and morphological–anatomical data. Maximum parsimony and Bayesian analyses were performed with sequences from three plastid DNA markers (trnSGGA-rps4 spacer, rps4 gene, trnLUAA intron), volatile oil compounds,

Michael Stech; Manuela Sim-Sim; M. Glória Esquível; Leena luís; Susana Fontinha; Carlos Lobo; César Garcia; Soraia Martins; Cristiana Vieira; José Barroso; Luis G. Pedro; A. Cristina S. Figueiredo

2010-01-01

326

Characterization of the morphological, physical, and mechanical properties of seven nonwood plant fiber bundles  

Microsoft Academic Search

The morphological, physical, and mechanical properties of the nonwood plant fiber bundles of ramie, pineapple, sansevieria,\\u000a kenaf, abaca, sisal, and coconut fiber bundles were investigated. All fibers except those of coconut fiber had noncircular\\u000a cross-sectional shapes. The crosssectional area of the fiber bundles was evaluated by an improved method using scanning electron\\u000a microscope images. The coefficient factor defined as the

Sasa Sofyan Munawar; Kenji Umemura; Shuichi Kawai

2007-01-01

327

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

328

Morphological, immunohistochemical and ultrastructural characterization of the skin of turbot (Psetta maxima L.).  

PubMed

This study was undertaken to identify the normal morphologic, immunohistochemical and ultrastructural features of skin of the turbot (Psetta maxima L.). In the turbot skin, three morphologically distinct layers were identified: epidermis, dermis and hypodermis. The epidermis was non-keratinizing, stratified squamous epithelium that varies in thickness from 5 to 14 cells and 60 to 100?m in size. Goblet cells were seen randomly distributed between malpighian cells in the epidermal layer. These mucous cells were mainly located in the upper third of the epidermis and displayed a spherical to elongated morphology. Dermis was divided in two well-differentiated layers, the superficial stratum laxum and the deeper stratum compactum. Hypodermis was a loose layer mainly composed by adipocytes but we could observe variable amounts of fibroblast, collagen and blood vessels. In turbot two pigmentary layers could be identified: the pigmentary layer of dermis was located between basement membrane and dermis and the pigmentary layer of hypodermis immediately above the muscular layer. Three different types of chromatophores were present: melanophores, iridophores and xanthophores. The main differences observed between groups of fish with different colouration were in the amount of melanophores and xanthophores. The purpose of this article is to provide an overview of normal cutaneous biology prior to consideration of specific cutaneous alterations and diseases in turbot. PMID:25059111

Faílde, L D; Bermúdez, R; Vigliano, F; Coscelli, G A; Quiroga, M I

2014-10-01

329

Characterization of angiotensin-binding sites in the bovine adrenal and the rat brain  

SciTech Connect

The first study was designed to determine whether systemically administered MSG affects neurons in the CVOs that are potentially important in mediating angiotensin-dependent responses. Rats were pretreated with MSG and the receptors for angiotensin II were assayed by radioligand binding in brain homogenates from the septum anteroventral third ventricular region (AV3V) and the thalamus/hypothalamus region using {sup 125}I-angiotensin II as the radioligand. The results of this experiment indicate that systematically administered MSG in the rat significantly reduced the number (Bmax) of Ang II receptors in a tissue sample which contained both extra blood-brain barrier organs as well as tissue within the blood-brain barrier with no change in the affinity (Kd) of the binding sites. The second chapter reports the successful solubilization of bovine adrenal {sup 125}I Ang II and {sup 125}I Sar{sup 1},Ile{sup 8}-Ang II binding sites with the detergent CHAPS. The results of our studies indicate the presence of two angiotensin binding sites. The one site is specific for naturally occurring angiotensins as well as sarcosine-1 substituted angiotensin analogues. The other site which can be optimally stabilized be re-addition of 0.3% CHAPS into the incubation assay binds sarcosine-1 substituted angiotensins exclusively. Hydrophobic interaction chromatography experiments suggest that these sites, possibly, represent distinct proteins. The third chapter discusses the successful solubilization and partial characterization of the rat brain angiotensin receptor.

Rogulja, I.

1989-01-01

330

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

331

Inhibition of Protein Kinases in Rat Pheochromocytoma (PC12) Cells Promotes Morphological Differentiation and Down-Regulates Ion Channel Expression  

Microsoft Academic Search

We have studied morphological differentiation and ion channel expression in PC12 cells under different culture conditions. Differentiation mediated by nerve growth factor (NGF) was compared with that induced by depletion and inhibition of protein kinases (phorbol ester beta -PMA plus staurosporine). Morphological differentiation was similar under both conditions. However, ion channel densities, studied by means of the patch-clamp technique, were

H. Reuter; A. Bouron; R. Neuhaus; C. Becker; B. F. X. Reber

1992-01-01

332

Effects of early and late adverse experiences on morphological characteristics of Sprague-Dawley rat liver subjected to stress during adulthood  

PubMed Central

The literature indicates that early rupture of the maternal bond and social isolation are variables involved in social and emotional behaviors and in increase in anxiety, particularly in stressful situations. The liver plays a role in the adaptation to stress, yet the possible morphologic changes that its structure can suffer have been studied very little. Therefore, the aim here was to ascertain, through the model of altering the early mother-infant bond and the late social bond through isolation, the effect on the stereologic characteristics of the liver in adult Sprague-Dawley rats subjected to intermittent chronic stress. Twenty-five newborn female rats were used, distributed into 5 groups, under standardized lactation and feeding conditions. The experimental groups were exposed to early (E1), late (E2), and early-late (E3) adverse experiences and then subjected to intermittent chronic stress in adulthood. The liver of each animal was isolated, and the stereologic characteristics of Nv, Vv, and Sv of the hepatocytes were determined. The results from the experimental groups were significantly higher than those obtained in the control groups. The highest values were found in group E3 (Nv = 4.43 ± 0.89 x 105/mm3, Vv = 68.74 ± 2.01%, Sv = 68.78 ± 3.77 mm2/mm3). Considering these results, the hepatic morphology can be affected by exposure to chronic stress; however, when the individuals have been subjected to previous adverse experiences, the changes are more evident. PMID:25197335

Vásquez, Bélgica; Sandoval, Cristian; Smith, Ricardo Luiz; del Sol, Mariano

2014-01-01

333

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...

334

Characterization of a rat model of metastatic prostate cancer bone pain  

PubMed Central

Purpose: The objectives of this study were to establish and characterize a novel animal model of metastatic prostate cancer-induced bone pain. Methods: Copenhagen rats were injected with 106 MATLyLu (MLL) prostate cancer cells or phosphate-buffered saline by per cutaneous intra femoral injections into the right hind leg distal epiphysis. Over 13 days, rats progressively developed a tumor within the distal femoral epiphysis. On days 3, 7, 10, and 13 post injection, rats were subjected to the incapacitance and Randall–Selitto behavioral tests as they are believed to be indirect reflections of tumor induced pain. Ipsilateral hind limbs were subjected to X-ray and computed tomography (CT) scans and histological sections were stained with hematoxylin and eosin (H&E). Results: Intra femoral injections of MLL cells resulted in the progressive development of a tumor leading to bone destruction and nociceptive behaviors. Tumor development resulted in the redistribution of weight to the contralateral hind leg and significantly reduced the paw withdrawal threshold of the ipsilateral hind paw as observed via the incapacitance and Randall–Selitto tests, respectively. X-ray and computed tomography scans along with H&E stains indicated tumor-associated structural damage to the distal femur. This model was challenged with administration of meloxicam. Compared with vehicle-injected controls, the meloxicam-treated rats displayed smaller nociceptive responses as observed with the incapacitance and Randall–Selitto tests, suggesting that meloxicam was effective in reducing the pain-related symptoms displayed by model animals and that the model behaved in a predictable way to cyclooxygenase-2 treatment. Conclusions: This model is unique from other bone cancer models in that it is a comprehensive model utilizing a competent immune system with a syngeneic tumor. The model establishes a tool that will be useful to investigate mechanisms of cancer pain that are induced by cancer cells. PMID:21197325

De Ciantis, Paolo Donato; Yashpal, Kiran; Henry, James; Singh, Gurmit

2010-01-01

335

Moment invariants for two-dimensional and three-dimensional characterization of the morphology of gamma-prime precipitates in nickel-base superalloys  

NASA Astrophysics Data System (ADS)

The relation between microstructural features and a material's properties is central to materials science. Certain morphological features of a microstructure can only be determined by 3-D characterization techniques, e.g. the connectivity of precipitates, and the true precipitate shape; others require geometric assumptions for stereological estimates, e.g. precipitate size distribution and the number of precipitates. When these inherently 3-D features affect the properties of a specific material, experimental techniques are necessary to investigate the 3-D nature of the microstructure, and to provide a more complete microstructural characterization. The quantitative description of 2-D and 3-D shapes is of fundamental importance to microstructural characterization. One approach to describing a microstructure is to characterize the shapes of individual precipitates. This characterization has typically been limited to particle size, aspect-ratio, and other qualitative descriptors. In general, these are insufficient and do not provide an adequate characterization in a way that allows for a direct comparison between different microstructures. This is evident during microstructure evolution when changes in precipitate morphology occur or when precipitates exhibit complex shapes. In this thesis, we show how moment invariants (combinations of second order moments that are invariant w.r.t. affine or similarity transformations) can be used as sensitive shape discriminators in 2-D and 3-D. This work focuses on the characterization of the two phase microstructure of nickel base superalloys and specically the gamma-prime (Ni3Al) precipitate morphology. Experimental data is collected by means of automated Focused-Ion Beam (FIB) based serial sectioning. Techniques for automated image processing and segmentation are developed which allow for direct conversion of raw serial-sectioning data to 3-D microstructural data. The gamma-prime precipitate morphology is characterized using second order moment invariants in conjunction with other shape parameters such as volume and surface area. This provides a quantitative description of the gamma-prime precipitate morphology and allows for variations in morphology to be identified.

Macsleyne, Jeremiah P.

336

First report, morphological and molecular characterization of Xiphinema elongatum and X. pachtaicum (Nematoda, Longidoridae) from Ethiopia  

PubMed Central

Abstract A total of six soil samples were collected around rhizosphere of citrus plants during 2010 from Melkassa Agricultural Research Center experimental station, Ethiopia. From these samples two most important ecto-plant parasitic nematodes of the genus Xiphinema were found and analysed. The genus Xiphinema is a large group of the phylum nematoda which constitutes more than 260 species. They are polyphagous root- ectoparasites of many crop plants and some species of this genus cause damage by direct feeding on root tips and transmit nepoviruses. The delimitation and discrimination of two species in the genus is presented, described herein as Xiphinema elongatum and Xiphinema pachtaicum. Morphological and morphometric data were done using light microscopy and results of both species were fit within the previously described nematode species of Xiphinema elongatum and Xiphinema pachtaicum. 18S rDNA were analysed using Bayesian inference (BI) method to reconstruct phylogenetic relationships of the studied Xiphinema sp. (KP407872 Xiphinema elongatum and KP407873 Xiphinema pachtaicum) with other Xiphinema species. The 18S rDNA sequence of Xiphinema pachtaicum was alike to previously described species from the GenBank but Xiphinema elongatum exhibited very small levels of nucleotides differences (0.4%) which might be possible intra-specific divergence. Though this region of rDNA has less resolution on complex species, its combination with morphological and morphometric analyses, suggests these species as Xiphinema elongatum and Xiphinema pachtaicum with the GenBank accession number of KP407872 and KP407873, respectively. Short notes, morphological measurements, illustrations, and molecular data are given to these species. These species are reported for the first time from Ethiopia and it provides new geographical information of these organisms. PMID:25878528

Getaneh, Gezahegne; Bert, Wim; Decraemer, Wilfrida

2015-01-01

337

Characterization of some morphological parameters of orbicularis oculi motor neurons in the monkey.  

PubMed

The primate facial nucleus is a prominent brainstem structure that is composed of cell bodies giving rise to axons forming the facial nerve. It is musculotopically organized, but we know little about the morphological features of its motor neurons. Using the Lucifer Yellow intracellular filling method, we examined 11 morphological parameters of motor neurons innervating the monkey orbicularis oculi (OO) muscle, which plays an important role in eyelid closure and voluntary and emotional facial expressions. All somata were multipolar and remained confined to the intermediate subnucleus, as did the majority of its aspiny dendritic branches. We found a mean maximal cell diameter of 54 microm in the transverse dimension, cell diameter of 60 microm in the rostrocaudal dimension, somal surface area of 17,500 microm(2) and somal volume of 55,643 microm(3). Eight neurons were used in the analysis of dendritic parameters based upon complete filling of the distal segments of the dendritic tree. We found a mean number of 16 dendritic segments, an average dendritic length of 1036 microm, diameter of 7 microm, surface area of 12,757 microm(2) and total volume of 16,923 microm(3). Quantitative analysis of the dendritic branch segments demonstrated that the average number, diameter and volume gradually diminished from proximal to distal segments. A Sholl analysis revealed that the highest number of dendritic intersections occurred 60 microm distal to the somal center with a gradual reduction of intersections occurring distally. These observations advance our understanding of the morphological organization of the primate facial nucleus and provide structural features for comparative studies, interpreting afferent influence on OO function and for designing studies pinpointing structural alterations in OO motor neurons that may accompany disorders affecting facial movement. PMID:18055128

McNeal, D W; Ge, J; Herrick, J L; Stilwell-Morecraft, K S; Morecraft, R J

2008-01-01

338

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

339

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

340

Characterization of Two ENU-Induced Mutations Affecting Mouse Skeletal Morphology  

PubMed Central

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

2013-01-01

341

Morphologic, Genetic, and Biochemical Characterization of Helicobacter Magdeburgensis, a Novel Species Isolated from the Intestine of Laboratory Mice  

PubMed Central

Background The presence of enterohepatic Helicobacter species (EHS) is commonly noted in mouse colonies. These infections often remain unrecognized but can cause severe health complications or more subtle host immune perturbations and therefore can confound the results of animal experiments. The aim of this study was to isolate and characterize a putative novel EHS that has previously been detected by PCR screening of specific-pathogen-free mice. Materials and Methods Biochemical analysis of enzyme activities (API campy), morphologic investigation (Gram-staining and electron microscopy) and genetic analyses (16SrRNA and 23SrRNA analyses, DNA fingerprinting, restriction fragment polymorphisms, and pulsed-field gel electrophoresis) were used to characterize isolated EHS. Genomic DNA fragments were sequenced to develop a species-specific PCR detection assay. Results Scanning electron microscopy revealed the presence of spiral-shaped EHS, which varied in length (2.5–6 µm) and contained single monopolar or single bipolar sheathed flagella. The bacteria were grown under anaerobic conditions, preferably on agar plates containing serum or blood. The 16SrRNA, genetic, and biochemical analyses indicated the identification of a novel EHS species, named Helicobacter magdeburgensis. We also examined the genome content using pulsed-field gel electrophoresis. Based on the pattern produced by two restriction enzymes, BamIII and KspI, the genome size was determined to be about 1.7–1.8 Mbp. Conclusion We isolated and characterized a novel EHS species, H. magdeburgensis, morphologically, biochemically, and genetically. These results are important for future studies on the prevalence and pathophysiologic relevance of such infections. Our PCR assay can be used to detect and discriminate H. magdeburgensis from other Helicobacter species. PMID:21083746

Traverso, Francisco Rivas; Bohr, Ulrich R. M.; Oyarzabal, Omar A.; Rohde, Manfred; Clarici, Alexandra; Wex, Thomas; Kuester, Doerthe; Malfertheiner, Peter; Fox, James G.; Backert, Steffen

2015-01-01

342

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

343

Light-Emitting Diodes and Cool White Fluorescent Light Similarly Suppress Pineal Gland Melatonin and Maintain Retinal Function and Morphology in the Rat. Part 1  

NASA Technical Reports Server (NTRS)

Currently, the light sources most commonly used in animal habitat lighting are cool white fluorescent or incandescent lamps. We evaluated a novel light-emitting diode (LED) light source for use in animal habitat lighting by comparing its effectiveness to cool white fluorescent light (CWF) in suppressing pineal gland melatonin and maintaining normal retinal physiology and morphology in the rat. Results of pineal melatonin suppression experiments showed equal suppression of pineal melatonin concentrations for LED light and CWF light at five different light illuminances (100, 40, 10, 1 and 0.1 lux). There were no significant differences in melatonin suppression between LED and CWF light when compared to unexposed controls. Retinal physiology was evaluated using electroretinography. Results show no differences in a-wave implicit times and amplitudes or b-wave implicit times and amplitudes between 100-lux LED-exposed rats and 100-lux CWF-exposed rats. Results of retinal histology assessment show no differences in retinal thickness rod outer segment length and number of rod nuclei between rats exposed to 100-lux LED and 100-lux CWF for days. Furthermore, the retinal pigmented epithelium and rod outer segments of all eyes observed were in good condition and of normal thickness. This study indicates that LED light does not cause retinal damage and can suppress pineal melatonin at similar intensities as a conventional CWF light source. These data suggest that LED light sources may be suitable replacements for conventional light sources used in the lighting of rodent vivariums while providing many mechanical and economical advantages.

Holley, Daniel C.; Heeke, D.; Mele, G.

1999-01-01

344

Anatomic Changes in the Macroscopic Morphology and Microarchitecture of Denervated Long Bone Tissue after Spinal Cord Injury in Rats  

PubMed Central

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

Maranho, Daniel A.; Butezloff, Mariana M.; Moura, Patrícia A.; Volpon, José Batista; Shimano, Antônio C.

2014-01-01

345

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, Saïd; Bourgoin, Sylvie; Kayser, Valérie; Barthélémy, Sandrine; Chevarin, Caroline; Chali, Farah; Orsal, Didier; Hamon, Michel

2014-01-01

346

Morphological evidence that luteinizing hormone-releasing hormone neurons participate in the suppression by estradiol of pituitary luteinizing hormone secretion in ovariectomized rats.  

PubMed

Morphological characteristics of LHRH neurons identified by immunocytochemistry were studied using light and electron microscopy in female rats in which estradiol was replaced at the time of ovariectomy ('pseudo-intact' rats) or 3 weeks after ovariectomy (long-term ovariectomized, estradiol-treated). While estradiol levels were equivalent in these two groups, the rise in LH after ovariectomy was prevented by the immediate administration in the pseudo-intact rats, while the augmented plasma LH levels present three weeks following ovariectomy were only reduced by 50% as a result of delayed estradiol treatment. The LHRH content of the medial basal hypothalamus (MBH) including the median eminence (ME) was greater in pseudo-intact females than in untreated long-term ovariectomized control females or long-term ovariectomized, estradiol-treated females, both 1 and 14 days after estradiol exposure. Immunocytochemistry revealed fewer LHRH-immunopositive neuronal processes coursing throughout the MBH and terminating in the ME of long-term ovariectomized, estradiol-treated rats compared to those in pseudo-intact rats. However, within individual neurovascular terminals in the ME, image analysis revealed that the area of reaction product was greater in long-term ovariectomized, estradiol-treated animals. Equivalent amounts of LHRH were assayed in the MBH within each group of animals by several LHRH antisera regardless of their different binding requirements (R42, IJ29 and A-R743), suggesting that the predominant moiety present in neuronal terminals is the fully mature decapeptide. In contrast, in the preoptic area-anterior hypothalamus (POA-AH) these antisera assayed amounts of LHRH that varied as a function of binding characteristics, although the quantities did not vary with the estradiol treatment schedule. Immunocytochemical results paralleled these assay data; antisera requiring an interior sequence of amino acids (A-R743 and A-R419) detected approximately 3 times as many immunoreactive perikarya in the POA-AH as did an antiserum requiring the free amidated C terminal (IJ29). The estradiol treatment schedules had no effect on the total number of LHRH-immunopositive neurons detected by each antiserum or the distribution of LHRH-immunopositive neuronal perikarya. These data support the hypothesis that the predominant moieties present in neuronal cell bodies are precursor forms. The fine-structural characteristics of LHRH-immunopositive neuronal cell bodies are consistent with greater secretory and biosynthetic activity in LHRH neurons of long-term ovariectomized, estradiol-treated rats.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3543719

King, J C; Anthony, E L; Damassa, D A; Elkind-Hirsch, K E

1987-01-01

347

Morphologic and Phylogenetic Characterization of Conidiobolus lamprauges Recovered from Infected Sheep?  

PubMed Central

Conidiobolus lamprauges, a soil and plant entomophthoralean fungus, has been reported only in a horse and, more recently, in sheep with rhinopharyngeal entomophthoramycosis. Thus, little information is available to enable proper identification of this pathogen and its differentiation from other saprotrophic and pathogenic Conidiobolus species. Using classical mycological tools and molecular methodologies, we report for the first time the taxonomic and phylogenetic description of three C. lamprauges isolates recovered from sheep with rhinopharyngeal entomophthoramycosis. The distinctive clinical and pathological features of C. lamprauges are compared with those of other Conidiobolus spp. affecting sheep, as well as with those of the stramenopilan ovine agent Pythium insidiosum. The comparative morphological attributes of Conidiobolus spp. are also diagramed; along with the sequence data generated, they should assist laboratories in the identification of these uncommon species. PMID:20007391

Vilela, Raquel; Silva, Silvana M. S.; Riet-Correa, Franklin; Dominguez, Eduardo; Mendoza, Leonel

2010-01-01

348

Morphological and molecular characterization of Magnaporthe oryzae (fungus) from infected rice leaf samples  

NASA Astrophysics Data System (ADS)

Magnaporthe oryzae is a plant-pathogenic fungus that causes a serious disease affecting rice called rice blast. Outbreaks of rice blast have been a threat to the global production of rice. This fungal disease is estimated to cause production losses of US55 million each year in South and Southeast Asia. It has been used as a primary model for elucidating various aspects of the host-pathogen interaction with its host. We have isolated five isolates of Magnaporthe oryzae from diseased leaf samples obtained from the field at Kompleks Latihan MADA, Kedah, Malaysia. We have identified the isolates using morphological and microscopic studies on the fungal spores and the lesions on the diseased leaves. Amplification of the internal transcribed spacer (ITS) was carried out with universal primers ITS1 and ITS4. The sequence of each isolates showed at least 99% nucleotide identity with the corresponding sequence in GenBank for Magnaporthe oryzae.

Muni, Nurulhidayah Mat; Nadarajah, Kalaivani

2014-09-01

349

Combining light microscopy, dielectric spectroscopy, MALDI intact cell mass spectrometry, FTIR spectromicroscopy and multivariate data mining for morphological and physiological bioprocess characterization of filamentous organisms.  

PubMed

Along with productivity and physiology, morphological growth behavior is the key parameter in bioprocess design for filamentous fungi. Lacking tools for fast, reliable and efficient analysis however, fungal morphology is still commonly tackled by empirical trial-and-error techniques during strain selection and process development procedures. Bridging the gap, this work presents a comprehensive analytical approach for morphological analysis combining automated high-throughput microscopy, multi-frequency dielectric spectroscopy, MALDI intact cell mass spectrometry and FTIR spectromicroscopy. Industrial fed-batch production processes were investigated in fully instrumented, automated bioreactors using the model system Penicillium chrysogenum. Physiological process characterization was based on the determination of specific conversion rates as scale-independent parameters. Conventional light microscopic morphological analysis was based on holistic determination of time series for more than 30 morphological parameters and their frequency distributions over the respective parameter range by automated high-throughput light microscopy. Characteristic protein patterns enriched in specific morphological and physiological states were further obtained by MALDI intact cell mass spectrometry. Spatial resolution of molecular biomass composition was facilitated by FTIR spectromicroscopy. Real-time in situ monitoring of morphological process behavior was achieved by linking multi-frequency dielectric spectroscopy with above outlined off-line methods. Data integration of complementing orthogonal techniques for morphological and physiological analysis together with multivariate modeling of interdependencies between morphology, physiology and process parameters facilitated complete bioprocess characterization. The suggested approach will thus help understanding morphological and physiological behavior and, in turn, allow to control and optimize those complex processes. PMID:23220594

Posch, Andreas E; Koch, Cosima; Helmel, Michaela; Marchetti-Deschmann, Martina; Macfelda, Karin; Lendl, Bernhard; Allmaier, Günter; Herwig, Christoph

2013-02-01

350

Electrophysiological and Morphological Characterization of Propriospinal Interneurons in the Thoracic Spinal Cord  

PubMed Central

Propriospinal interneurons in the thoracic spinal cord have vital roles not only in controlling respiratory and trunk muscles, but also in providing possible substrates for recovery from spinal cord injury. Intracellular recordings were made from such interneurons in anesthetized cats under neuromuscular blockade and with the respiratory drive stimulated by inhaled CO2. The majority of the interneurons were shown by antidromic activation to have axons descending for at least two to four segments, mostly contralateral to the soma. In all, 81% of the neurons showed postsynaptic potentials (PSPs) to stimulation of intercostal or dorsal ramus nerves of the same segment for low-threshold (?5T) afferents. A monosynaptic component was present for the majority of the peripherally evoked excitatory PSPs. A central respiratory drive potential was present in most of the recordings, usually of small amplitude. Neurons depolarized in either inspiration or expiration, sometimes variably. The morphology of 17 of the interneurons and/or of their axons was studied following intracellular injection of Neurobiotin; 14 axons were descending, 6 with an additional ascending branch, and 3 were ascending (perhaps actually representing ascending tract cells); 15 axons were crossed, 2 ipsilateral, none bilateral. Collaterals were identified for 13 axons, showing exclusively unilateral projections. The collaterals were widely spaced and their terminations showed a variety of restricted locations in the ventral horn or intermediate area. Despite heterogeneity in detail, both physiological and morphological, which suggests heterogeneity of function, the projections mostly fitted a consistent general pattern: crossed axons, with locally weak, but widely distributed terminations. PMID:21106900

Saywell, S. A.; Ford, T. W.; Meehan, C. F.; Todd, A. J.

2011-01-01

351

Biochemical and morphological characterization of the nuclear matrix during the synchronous cell cycle of Physarum polycephalum.  

PubMed

We have investigated biochemical and ultrastructural aspects of the nuclear matrix during the naturally synchronous cell cycle of Physarum polycephalum. The morphology of the in situ nuclear matrix exhibited significant cell cycle changes as revealed by electron microscopic examination, especially during the progression of nuclei through mitosis and S-phase. In mitosis the interchromatin matrix was found to be retracted to the nuclear periphery; during S-phase this interchromatin matrix gradually resembled, concomitant with the reconstruction of a nucleolar remnant structure. During the G2-period no significant changes in matrix morphology were observed. The pattern of nuclear matrix proteins was invariant during the cell cycle; no cycle phase-specific proteins could be detected. In vivo labelling of plasmodia with [35S]methionine/cysteine showed that only a few proteins are synthesized and assembled into nuclear matrix structures in a cell cycle-dependent way; the majority of proteins were synthesized almost continuously. This was also shown for nuclear lamins homologues. In contrast to bulk nuclear histones, those histones that remain tightly bound to the nuclear matrix were synthesized and assembled into nuclear structures in the very first hour of S-phase; assembly was terminated in mid-S-phase, indicating that nuclear matrix-bound chromatin is replicated early in S-phase. Comparison of the acetylation pattern of matrix-bound histone H4 with bulk nuclear H4 revealed a largely elevated acetate content of matrix H4. The percentage of acetylated subspecies was entirely different from that in bulk nuclear H4, indicating that matrix-associated histones represent a subpopulation of nuclear histones with distinct properties, reflecting specific structural requirements of matrix-attached chromatin. PMID:7693736

Lang, S; Decristoforo, T; Waitz, W; Loidl, P

1993-08-01

352

Morphological and spectroscopic characterization of laser-ablated tungsten at various laser irradiances  

NASA Astrophysics Data System (ADS)

The variation in surface morphology and plasma parameters of laser irradiated tungsten has been investigated as a function of irradiance. For this purpose, Nd:YAG laser (1064 nm, 10 ns, 10 Hz) is employed. Tungsten targets were exposed to various laser irradiances ranging from 6 to 50 GW/cm2 under ambient environment of argon at a pressure of 20 Torr. Scanning electron microscope analysis has been performed to analyze the surface modification of irradiated tungsten. It revealed the formation of micro- and nanoscale surface structures. In central ablated area, distinct grains and crack formation are observed, whereas peripheral ablated areas are dominated by cones and pinhole formation. It was observed that at irradiances exceeding a value of 13 GW/cm2, the morphological trend of the observed structures has been changed from erosion to melting and re-deposition dominant phase. Ablation efficiency as a function of laser irradiance has also been investigated by measuring the crater depth using surface profilometry analysis. It is found to be maximum at an irradiance of 13 GW/cm2 and decreases at high laser irradiances. In order to correlate the accumulated effects of plasma parameters with the surface modification, laser-induced breakdown spectroscopy analysis has been performed. The electron temperature and number density of tungsten plasma have been evaluated at various laser irradiances. Initially with the increase of the laser irradiance up to 13 GW/cm2, an increasing trend is observed for both plasma parameters due to enhanced energy deposition. Afterward, a decreasing trend is achieved which is attributed to the shielding effect. With further increase in irradiance, a saturation stage comes and insignificant changes are observed in plasma parameters. This saturation is explainable on the basis of the formation of a self-regulating regime near the target surface. Surface modifications of laser irradiated tungsten have been correlated with plasma parameters.

Akram, Mahreen; Bashir, Shazia; Rafique, Muhammad Shahid; Hayat, Asma; Mahmood, Khaliq; Dawood, Asadullah; Bashir, M. F.

2015-03-01

353

Morphological and molecular characterization of Pratylenchus lentis n. sp. (Nematoda: Pratylenchidae) from Sicily  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pratylenchus lentis n. sp. parasitizing roots of lentil in Sicily, Italy, is described and illustrated. The new species is characterized by a high lip region with three annuli, stylet mean length of 16 micrometers with anteriorly flattened knobs, cylindrical body with a relatively anterior vulva, l...

354

Compositional, morphological, and hysteresis characterization of magnetic airborne particulate matter in Rome, Italy  

Microsoft Academic Search

The magnetic properties of tree leaves may be used to delineate the abundance and dispersal of anthropogenic airborne particulate matter (PM) in urban environments. In the city of Rome, Italy, circulating vehicles are the main source of magnetic PM, already characterized as prevalently low-coercivity, magnetite-like particles. To further constrain the nature and origin of such magnetic particles, we carried out

Leonardo Sagnotti; Jacopo Taddeucci; Aldo Winkler; Andrea Cavallo

2009-01-01

355

CHARACTERIZATION OF FUNGI FROM HYPERSALINE ENVIRONMENTS OF SOLAR SALTERNS USING MORPHOLOGICAL AND MOLECULAR TECHNIQUES  

EPA Science Inventory

The Cabo Rojo Solar Salterns located on the southwest coast of Puerto Rico are composed of two main ecosystems (i.e., salt ponds and microbial mats). Even though these locations are characterized by high solar radiation (mean light intensity of 39 mol photons m-2d-1) they harbor ...

356

Morphology and Characterization of Ditch Soils at an Atlantic Coastal Plain Farm  

Technology Transfer Automated Retrieval System (TEKTRAN)

Some materials in drainage ditches, which have traditionally been referred to and studied as sediments, may be soils. In this study, we described and characterized materials found in agricultural ditches at the University of Maryland Eastern Shore Research Farm (Princess Anne, MD). Sixty-nine profil...

357

Morphological and biological characterization of cell line developed from bovine Echinococcus granulosus  

Microsoft Academic Search

The taeniid tapeworm Echinococcus granulosus is the causative agent of echinococcal disease, a major zoonosis with worldwide distribution. Several efforts to establish\\u000a an in vitro model of E. granulosus have been undertaken; however, many of them have been designed for Echinococcus multilocularis. In the present study, we have described and characterized a stable cell line obtained from E. granulosus bovine

Claudia I. Echeverría; Dora M. Isolabella; Elio A. Prieto Gonzalez; Araceli Leonardelli; Laura Prada; Alina Perrone; Alicia G. Fuchs

2010-01-01

358

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

359

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

360

Morphological characterization of extremely shallow environments through spectral and textural analysis of high resolution bathymetric and backscatter data  

NASA Astrophysics Data System (ADS)

Transitional environments like lagoons, deltas and estuaries often undergo strong natural and human-induced actions that need constant monitoring. The changes of these environments can be assessed using acoustic bathymetric surveys: bathymetric data are not only important for navigational purposes but they are also employed for geomorphologic studies, habitat mapping and modelling of evolution trends of the highly dynamical coastal areas. Among the coastal systems, transitional environments, are often extremely shallow (of the order of 1 m deep or less) and morphologically complex. This kind of environment represents a challenge for acoustic bathymetric surveys. To assess the potentiality and the limits of acoustic surveys in extremely shallow environments, we carried out two surveys in the Lagoon of Venice, Italy, with an interferometric sonar and a multibeam echosounder system. As a case study we focused on a natural channel in the northern part of the lagoon combining the data from the different surveys. In particular we carried out a two-dimensional (2D) spectral and textural analysis of the high resolution bathymetric and backscatter data collected. As a result of the 2D spectral analysis on the elevation data, we were able to identify and parameterize the geometrical characteristics of the main morphological features of the channel, like dunes, scours, crests and troughs and sedimentation areas and to extract the channel bottom roughness. We then performed an unsupervised classification of the backscatter data. As a result, we were able to identify different backscatter areas where several grab samples were collected for ground truthing. With the help of this sampling we calibrated a textural analysis and obtained a classification of the different kinds of substrate. Within this multidisciplinary approach, we set up and successfully tested a combined method to quantitatively characterize an extremely shallow water dynamical environment. Using this method, we could map the main morphological and sedimentological features of the seabed and relate them to the hydrodynamic conditions provided by an high resolution 3D numerical model.

Madricardo, Fantina; Foglini, Federica; Tegowski, Jaroslaw; Blondel, Philippe; Nowak, Jaroslaw; Ferrarin, Christian

2013-04-01

361

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

362

Morphological, genotypic, and physiological characterization of Acanthamoeba isolates from keratitis patients and the domestic environment in Vitoria, Espírito Santo, Brazil.  

PubMed

Amoebae of the genus Acanthamoeba are free-living protozoa that can cause granulomatous encephalitis and keratitis in humans. In this study, four clinical and three household dust isolates obtained in Vitória, Espírito Santo, Brazil were characterized by their morphological, genotypic, and physiological properties. All isolates belonged to group II according to Pussard and Pons' cyst morphology. Analysis of their 18S rDNA sequence identified one isolate from household dust as genotype T11 and the others six samples as genotype T4. Five T4 isolates presented a highly variable region (DF3) in 18S rDNA identical to those previously described. Physiological assays carried out with trophozoites in co-culture with bacteria or in axenic conditions showed all samples tolerated temperatures up to 37°C, regardless of culture method. One keratitis isolate grew at 42°C in co-culture with bacteria. Most isolates in co-culture survived at 1.0M, except a T11 isolate, which tolerated up to 0.5M. The isolates did not grow at 42°C and did not tolerate 0.5M and 1.0M under axenic condition. This is the first report of 18S rRNA gene genotyping applied to Acanthamoeba isolated from keratitis patients in Brazil. The results also indicated that osmo-tolerance is dependent on the culture system. PMID:23748160

Duarte, Juliana L; Furst, Cinthia; Klisiowicz, Débora R; Klassen, Giseli; Costa, Adriana O

2013-09-01

363

Identification and characterization of a set of conserved and new regulators of cytoskeletal organization, cell morphology and migration  

PubMed Central

Background Cell migration is essential during development and in human disease progression including cancer. Most cell migration studies concentrate on known or predicted components of migration pathways. Results Here we use data from a genome-wide RNAi morphology screen in Drosophila melanogaster cells together with bioinformatics to identify 26 new regulators of morphology and cytoskeletal organization in human cells. These include genes previously implicated in a wide range of functions, from mental retardation, Down syndrome and Huntington's disease to RNA and DNA-binding genes. We classify these genes into seven groups according to phenotype and identify those that affect cell migration. We further characterize a subset of seven genes, FAM40A, FAM40B, ARC, FMNL3, FNBP3/FBP11, LIMD1 and ZRANB1, each of which has a different effect on cell shape, actin filament distribution and cell migration. Interestingly, in several instances closely related isoforms with a single Drosophila homologue have distinct phenotypes. For example, FAM40B depletion induces cell elongation and tail retraction defects, whereas FAM40A depletion reduces cell spreading. Conclusions Our results identify multiple regulators of cell migration and cytoskeletal signalling that are highly conserved between Drosophila and humans, and show that closely related paralogues can have very different functions in these processes. PMID:21834987

2011-01-01

364

Surface morphology, microstructure, raman characterization and magnetic ordering of oxidized Fe-sputtered films on silicon substrate  

NASA Astrophysics Data System (ADS)

Iron oxide (Fe2O3) nanostructures are synthesized by thermal oxidation of Fe-sputtered films in a carbon-rich environment. Nanocrystals and nanoparticle networks are observed to grow on oxidized Fe thin films. Xray diffraction (XRD) characterization of samples reveals the existence of rhombohedral Fe2O3 crystal structure. Raman spectroscopy of annealed films shows the existence of Fe3O4 phase on network like structures which is brought about by the surface stress between the two iron oxide phases. Atomic force microscope (AFM) phase image of the Fe2O3 film shows a large scale magnetic ordering which does not depend on the surface morphology of the sample.

Jasmin, A.; Rillera, H.; Semblante, O.; Sarmago, R.

2012-09-01

365

Characterization of the Etna volcanic emissions through an active biomonitoring technique (moss-bags): part 2--morphological and mineralogical features.  

PubMed

Volcanic emissions were studied at Mount Etna (Italy) by using moss-bags technique. Mosses were exposed around the volcano at different distances from the active vents to evaluate the impact of volcanic emissions in the atmosphere. Morphology and mineralogy of volcanic particulate intercepted by mosses were investigated using scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS). Particles emitted during passive degassing activity from the two active vents, Bocca Nuova and North East Crater (BNC and NEC), were identified as silicates, sulfates and halide compounds. In addition to volcanic particles, we found evidences also of geogenic, anthropogenic and marine spray input. The study has shown the robustness of this active biomonitoring technique to collect particles, very useful in active volcanic areas characterized by continuous degassing and often not easily accessible to apply conventional sampling techniques. PMID:25311770

Calabrese, S; D'Alessandro, W

2015-01-01

366

Characterization of lake minnow Eupallasella percnurus semen in relation to sperm morphology, regulation of sperm motility and interpopulation diversity.  

PubMed

Sperm morphology and regulation of sperm motility of lake minnow Eupallasella percnurus, an endangered cyprinid, were investigated. Milt characteristics from two isolated populations of E. percnurus were compared to characterize the interpopulation diversity. Electron microscopic studies revealed that E. percnurus spermatozoa comprise simple, uniflagellate, anacrosomal aquasperm with species-specific features as an eccentrically located implantation of nuclear fossa and eccentric insertion of flagellum. Sperm motility was significantly inhibited by relatively low ion concentrations (150, 150 and 8 mM for NaCl, KCl and CaCl2 , respectively). Sperm maintained a high motility rate over a wide pH range (5.5-10.5), which may reflect adaptation to a highly variable environment. The two E. percnurus populations were markedly different in milt volume, sperm concentration, seminal plasma pH, sperm motility and beat cross frequency, which may result from genetic differences and environmental conditions. PMID:24961489

Dietrich, G J; Pecio, A; Sikorska, J; Wolnicki, J; S?owi?ska, M; Hliwa, P; Kami?ski, R; Andronowska, A; Ciereszko, A

2014-08-01

367

Morphological and ribosomal DNA-based characterization of six Antarctic ciliate morphospecies from the Amundsen Sea with phylogenetic analyses.  

PubMed

We characterized six tintinnid ciliates from Antarctic waters using molecular markers and morphological traits: Amphorellopsis quinquealata, Codonellopsis gaussi, Cymatocylis convallaria, Cy. calyciformis, Cy. drygalskii, and Laackmanniella prolongata. The 100% similarity in SSU-ITS1-5.8S rDNA-ITS2-partial LSU rDNA sequences among Cy. convallaria, Cy. calyciformis, and Cy. drygalskii is supportive of synonymy. Codonellopsis gaussi and L. prolongata also showed high levels of similarity in SSU rDNA (99.83%) and the D2 domain of LSU rDNA (95.77%), suggesting that they are closely related. Phylogenetic analysis placed Cymatocylis in the Rhabdonellidae, Amphorellopsis in the Tintinnidae and L. prolongata/Co. gaussi within the Dictyocystidae. PMID:23865618

Kim, Sun Young; Choi, Joong Ki; Dolan, John R; Shin, Hyoung Chul; Lee, SangHoon; Yang, Eun Jin

2013-01-01

368

Connexin36 identified at morphologically mixed chemical/electrical synapses on trigeminal motoneurons and at primary afferent terminals on spinal cord neurons in adult mouse and rat  

PubMed Central

Morphologically mixed chemical/electrical synapses at axon terminals, with the electrical component formed by gap junctions, is common in the CNS of lower vertebrates. In mammalian CNS, evidence for morphologically mixed synapses has been obtained in only a few locations. Here, we used immunofluorescence approaches to examine the localization of the neuronally expressed gap junction forming protein connexin36 (Cx36) in relation to the axon terminal marker vesicular glutamate transporter1 (vglut1) in spinal cord and trigeminal motor nucleus (Mo5) of rat and mouse. In adult rodents, immunolabelling for Cx36 appeared exclusively as Cx36-puncta, and was widely distributed at all rostro-caudal levels in most spinal cord laminae and in the Mo5. A high proportion of Cx36-puncta was co-localized with vglut1, forming morphologically mixed synapses on motoneurons, in intermediate spinal cord lamina, and in regions of medial lamina VII, where vglut1-containing terminals associated with Cx36 converged on neurons adjacent to the central canal. Unilateral transection of lumbar dorsal roots reduced immunolabelling of both vglut1 and Cx36 in intermediate laminae and lamina IX. Further, vglut1-terminals displaying Cx36-puncta were contacted by terminals labelled for glutamic acid decarboxylase65, which is known to be contained in presynaptic terminals on large diameter primary afferents. Developmentally, mixed synapses begin to emerge in the spinal cord only after the second to third postnatal week and thereafter increase to adult levels. Our findings demonstrate that axon terminals of primary afferent origin form morphologically mixed synapses containing Cx36 in broadly distributed areas of adult rodent spinal cord and Mo5. PMID:24406437

Bautista, W.; McCrea, D. A.; Nagy, J. I.

2014-01-01

369

Isolation and Characterization of Antibody Fragments Selective for Specific Protein Morphologies from Nanogram Antigen Samples  

PubMed Central

We developed atomic force microscope (AFM) based protocols that enable isolation and characterization of antibody based reagents that selectively bind target protein variants using low nanogram amounts or less of unpurified starting material. We isolated single chain antibody fragments (scFvs) that specifically recognize an oligomeric amyloid-beta (A?) species correlated with Alzheimer’s disease (AD) using only a few nanograms of an enriched but not purified sample obtained from human AD brain tissue. We employed several subtractive panning steps to remove all phage binding non-desired antigens and then employed a single positive panning step using minimal antigen. We also used AFM to characterize the specificity of the isolated clones, again using minimal material, selecting the C6 scFv based on expression levels. We show that C6 selectively binds cell and brain derived oligomeric A?. The protocols described are readily adapted to isolating antibody based reagents against other antigenic targets with limited availability. PMID:23359572

Kasturirangan, Srinath; Reasoner, Tim; Schulz, Philip; Boddapati, Shanta; Emadi, Sharareh; Valla, Jon; Sierks, Michael R.

2013-01-01

370

Synthesis and characterization of Ag\\/Cu\\/HAP with platelet morphology  

Microsoft Academic Search

As a useful starting material in coating technology and preparation of HAP\\/polymers composites the platelet Ag\\/Cu\\/HAP was\\u000a prepared using the solid solution of HAP reacting with the mix-solution of silver and copper nitrate. Its composition, microstructure\\u000a and properties were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform\\u000a infrared spectroscopy (FTIR) and anti-bacterial or bacteriostatic tests.

Hui Yang; Bingjuan Xiao; Ke-Wei Xu

2009-01-01

371

Characterization of rat serum amyloid A4 (SAA4): a novel member of the SAA superfamily.  

PubMed

The serum amyloid A (SAA) family of proteins is encoded by multiple genes, which display allelic variation and a high degree of homology in mammals. The SAA1/2 genes code for non-glycosylated acute-phase SAA1/2 proteins, that may increase up to 1000-fold during inflammation. The SAA4 gene, well characterized in humans (hSAA4) and mice (mSaa4) codes for a SAA4 protein that is glycosylated only in humans. We here report on a previously uncharacterized SAA4 gene (rSAA4) and its product in Rattus norvegicus, the only mammalian species known not to express acute-phase SAA. The exon/intron organization of rSAA4 is similar to that reported for hSAA4 and mSaa4. By performing 5'- and 3'RACE, we identified a 1830-bases containing rSAA4 mRNA (including a GA-dinucleotide tandem repeat). Highest rSAA4 mRNA expression was detected in rat liver. In McA-RH7777 rat hepatoma cells, rSAA4 transcription was significantly upregulated in response to LPS and IL-6 while IL-1?/? and TNF? were without effect. Luciferase assays with promoter-truncation constructs identified three proximal C/EBP-elements that mediate expression of rSAA4 in McA-RH7777 cells. In line with sequence prediction a 14-kDa non-glycosylated SAA4 protein is abundantly expressed in rat liver. Fluorescence microscopy revealed predominant localization of rSAA4-GFP-tagged fusion protein in the ER. PMID:25044109

Rossmann, Christine; Windpassinger, Christian; Brunner, Daniela; Kovacevic, Alenka; Schweighofer, Natascha; Malli, Roland; Schuligoi, Rufina; Prokesch, Andreas; Kluve-Beckerman, Barbara; Graier, Wolfgang F; Kratky, Dagmar; Sattler, Wolfgang; Malle, Ernst

2014-08-01

372

Characterization of oleic acid-induced acute respiratory distress syndrome model in rat.  

PubMed

Animal studies using oleic acid (OA) model to produce acute respiratory distress syndrome (ARDS) have been inconsistent. Therefore, the present study was undertaken to establish an acute model of ARDS in rats using OA and to characterize its effect on cardio-respiratory parameters and lethality. The trachea, jugular vein and femoral artery of anesthetized adult rats were cannulated. A dose of OA (30-90 microL; iv) was injected in each animal and changes in respiratory frequency (RF), heart rate (HR) and mean arterial pressure (MAP) were recorded. Minute ventilation and PaO2/FiO2 (P/F) ratio were also determined. At the end, lungs were excised for determination of pulmonary water content and histological examination. At all doses of OA, there was immediate decrease followed by increase in RF, however at 75 and 90 microL of OA, RF decreased abruptly and the animals died by 63 +/- 8.2 min and 19 +/- 6.3 min; respectively. In all the groups, HR and MAP changes followed the respiratory changes. The minute ventilation increased in a dose-dependent manner while the values of P/F ratio decreased correspondingly. Pulmonary edema was induced at all doses. Histological examination of the lung showed alveolar damage, microvascular congestion, microvascular injury, infiltration of inflammatory cells, pulmonary edema and necrosis in a dose-dependent manner. With these results, OA can be used to induce different grades of ARDS in rats and OA doses of 50, 60 and 75 microL resemble mild, moderate and severe forms of ARDS respectively. Hence, OA model serves as a useful tool to study the pathophysiology of ARDS. PMID:25059039

Akella, Aparna; Sharma, Parul; Pandey, Ratna; Deshpande, Shripad B

2014-07-01

373

Characterization of rat serum amyloid A4 (SAA4): A novel member of the SAA superfamily  

PubMed Central

The serum amyloid A (SAA) family of proteins is encoded by multiple genes, which display allelic variation and a high degree of homology in mammals. The SAA1/2 genes code for non-glycosylated acute-phase SAA1/2 proteins, that may increase up to 1000-fold during inflammation. The SAA4 gene, well characterized in humans (hSAA4) and mice (mSaa4) codes for a SAA4 protein that is glycosylated only in humans. We here report on a previously uncharacterized SAA4 gene (rSAA4) and its product in Rattus norvegicus, the only mammalian species known not to express acute-phase SAA. The exon/intron organization of rSAA4 is similar to that reported for hSAA4 and mSaa4. By performing 5?- and 3?RACE, we identified a 1830-bases containing rSAA4 mRNA (including a GA-dinucleotide tandem repeat). Highest rSAA4 mRNA expression was detected in rat liver. In McA-RH7777 rat hepatoma cells, rSAA4 transcription was significantly upregulated in response to LPS and IL-6 while IL-1?/? and TNF? were without effect. Luciferase assays with promoter-truncation constructs identified three proximal C/EBP-elements that mediate expression of rSAA4 in McA-RH7777 cells. In line with sequence prediction a 14-kDa non-glycosylated SAA4 protein is abundantly expressed in rat liver. Fluorescence microscopy revealed predominant localization of rSAA4-GFP-tagged fusion protein in the ER. PMID:25044109

Rossmann, Christine; Windpassinger, Christian; Brunner, Daniela; Kovacevic, Alenka; Schweighofer, Natascha; Malli, Roland; Schuligoi, Rufina; Prokesch, Andreas; Kluve-Beckerman, Barbara; Graier, Wolfgang F.; Kratky, Dagmar; Sattler, Wolfgang; Malle, Ernst

2014-01-01

374

Heterologous expression, purification and characterization of rat class theta glutathione transferase T2-2.  

PubMed Central

Rat glutathione transferase (GST) T2-2 of class Theta (rGST T2-2), previously known as GST 12-12 and GST Yrs-Yrs, has been heterologously expressed in Escherichia coli XLI-Blue. The corresponding cDNA was isolated from a rat hepatoma cDNA library, ligated into and expressed from the plasmid pKK-D. The sequence is the same as that of the previously reported cDNA of GST Yrs-Yrs. The enzyme was purified using ion-exchange chromatography followed by affinity chromatography with immobilized ferric ions, and the yield was approx. 200 mg from a 1 litre bacterial culture. The availability of a stable recombinant rGST T2-2 has paved the way for a more accurate characterization of the enzyme. The functional properties of the recombinant rGST T2-2 differ significantly from those reported earlier for the enzyme isolated from rat tissues. These differences probably reflect the difficulties in obtaining fully active enzyme from sources where it occurs in relatively low concentrations, which has been the case in previous studies. 1-Chloro-2,4-dinitrobenzene, a substrate often used with GSTs of classes Alpha, Mu and Pi, is a substrate also for rGST T2-2, but the specific activity is relatively low. The Km value for glutathione was determined with four different electrophiles and was found to be in the range 0.3 mM-0.8 mM. The Km values for some electrophilic substrates were found to be in the micromolar range, which is low compared with those determined for GSTs of other classes. The highest catalytic efficiency was obtained with menaphthyl sulphate, which gave a Kcat/Km value of 2.3 x 10(6) s-1.M-1 and a rate enhancement over the uncatalysed reaction of 3 x 10(10). PMID:8645195

Jemth, P; Stenberg, G; Chaga, G; Mannervik, B

1996-01-01

375

Heterologous expression, purification and characterization of rat class theta glutathione transferase T2-2.  

PubMed

Rat glutathione transferase (GST) T2-2 of class Theta (rGST T2-2), previously known as GST 12-12 and GST Yrs-Yrs, has been heterologously expressed in Escherichia coli XLI-Blue. The corresponding cDNA was isolated from a rat hepatoma cDNA library, ligated into and expressed from the plasmid pKK-D. The sequence is the same as that of the previously reported cDNA of GST Yrs-Yrs. The enzyme was purified using ion-exchange chromatography followed by affinity chromatography with immobilized ferric ions, and the yield was approx. 200 mg from a 1 litre bacterial culture. The availability of a stable recombinant rGST T2-2 has paved the way for a more accurate characterization of the enzyme. The functional properties of the recombinant rGST T2-2 differ significantly from those reported earlier for the enzyme isolated from rat tissues. These differences probably reflect the difficulties in obtaining fully active enzyme from sources where it occurs in relatively low concentrations, which has been the case in previous studies. 1-Chloro-2,4-dinitrobenzene, a substrate often used with GSTs of classes Alpha, Mu an