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1

EARLY EFFECTS OF TRIMETHYLTIN ON THE DENTATE GYRUS BASKET CELLS: A MORPHOLOGICAL STUDY  

EPA Science Inventory

Electrophysiological evidence for reduction of recurrent inhibition in the dentate gyrus in animals exposed to trimethyltin (TMT) suggested alterations in the inhibitory neurons (basket cells) by TMT. The present study was designed to investigate the morphology of basket cells af...

2

Viral infection in placenta relevant cells - a morphological and immunohistochemical cell culture study.  

PubMed

Viral infections in pregnancy are known to cause fetal malformation, growth restriction, and even fetal death. Macroscopic placental examination usually shows slight and unspecific changes. Histology may show secondary, non-specific tissue reaction, i.e. villitis with lymphocytic invasion. Primary specific morphology characteristics are known for some virus, like cytomegalovirus, parvovirus, and herpes simplex, however many viral infections show non-specific changes. Placenta relevant cells as human first trimester trophoblasts HTR8/SVneo, primary human umbilical vein endothelial cells (HUVEC), and primary human embryonic fibroblasts were examined following infection with commonly occurring virus like adenovirus and enterovirus. Morphology in routine stained sections and virus-specific immunostains were studied 4, 8, 24, 48, 72 h after infection. Nuclear enlargement was seen in the infected cells. A specific diagnosis of adenovirus or enterovirus infection, however, was not possible without specific immunostains. PMID:25244625

Turowski, Gitta; Rollag, Halvor; Roald, Borghild

2015-01-01

3

Morphology and size of stem cells from mouse and whale: observational study  

PubMed Central

Objective To compare the morphology and size of stem cells from two mammals of noticeably different body size. Design Observational study. Setting The Netherlands. Participants A humpback whale (Megaptera novaeangliae) and a laboratory mouse (Mus musculus). Main outcome measures Morphology and size of mesenchymal stem cells from adipose tissue. Results Morphologically, mesenchymal stem cells of the mouse and whale are indistinguishable. The average diameter of 50 mesenchymal stem cells from the mouse was 28 (SD 0.86) µm and 50 from the whale was 29 (SD 0.71) µm. The difference in cell size between the species was not statistically significant. Although the difference in bodyweight between the species is close to two million-fold, the mesenchymal stem cells of each were of similar size. Conclusions The mesenchymal stem cells of whales and mice are alike, in both morphology and size. PMID:24336001

2013-01-01

4

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

PubMed

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

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

2011-09-30

5

Primary culture of trigeminal satellite glial cells: a cell-based platform to study morphology and function of peripheral glia.  

PubMed

Primary cell culture provides an experimental platform in which morphology, physiology, and cell-cell communication pathways can be studied under a well-controlled environment. Primary cell cultures of peripheral and central glia offer unique possibilities to clarify responses and pathways to different stimuli. Peripheral glia, satellite glial cells (SGCs), which surround neuronal cell bodies within sensory ganglia, have recently been known as key players in inflammation and neuronal sensitization. The objectives of this study were 1) to establish a cell-based platform of cultured trigeminal SGCs to study glial marker expression and functions under control conditions; 2) to validate the cell-based platform by prostaglandin E2 (PGE2) release response following administration of Cisplatin; and 3) to investigate inhibition of PGE2 release by glial modulators, Ibudilast and SKF86002. Primary cell cultures of SGCs from rat trigeminal ganglia were established following enzymatically and mechanically dissociation of the ganglia. Cultures were characterized in vitro for up to 21 days post isolation for morphological and immunocytochemical characteristics. PGE2 release, determined by ELISA, was used as a pro-inflammatory marker to characterize SGCs response to chemotherapeutic agent, Cisplatin, known to contribute in chemotherapy-induced peripheral neuropathy. Our results indicate that 1) isolated SGCs maintained their characteristics in vitro for up to 21 days; 2) Cisplatin enhanced PGE2 release from the SGCs, which was attenuated by Ibudilast and SKF86002. These findings confirm the utility and validity of the cultured trigeminal SGCs platform for glial activation and modulation; and suggest further investigation on Ibudilast and SKF86002 in prevention of chemotherapy-induced pain. PMID:24665354

Poulsen, Jeppe N; Larsen, Frederik; Duroux, Meg; Gazerani, Parisa

2014-01-01

6

Solvent polarity and nanoscale morphology in bulk heterojunction organic solar cells: A case study  

NASA Astrophysics Data System (ADS)

Organic bulk heterojunction solar cells were fabricated under identical experimental conditions, except by varying the solvent polarity used for spin coating the active layer components and their performance was evaluated systematically. Results showed that presence of nitrobenzene-chlorobenzene composition governs the morphology of active layer formed, which is due to the tuning of solvent polarity as well as the resulting solubility of the P3HT:PCBM blend. Trace amount of nitrobenzene favoured the formation of better organised P3HT domains, as evident from conductive AFM, tapping mode AFM and surface, and cross-sectional SEM analysis. The higher interfacial surface area thus generated produced cells with high efficiency. But, an increase in the nitrobenzene composition leads to a decrease in cell performance, which is due to the formation of an active layer with larger size polymer domain networks with poor charge separation possibility.

Thomas, Ajith; Elsa Tom, Anju; Rao, Arun D.; Varman, K. Arul; Ranjith, K.; Vinayakan, R.; Ramamurthy, Praveen C.; Ison, V. V.

2014-03-01

7

Solvent polarity and nanoscale morphology in bulk heterojunction organic solar cells: A case study  

SciTech Connect

Organic bulk heterojunction solar cells were fabricated under identical experimental conditions, except by varying the solvent polarity used for spin coating the active layer components and their performance was evaluated systematically. Results showed that presence of nitrobenzene-chlorobenzene composition governs the morphology of active layer formed, which is due to the tuning of solvent polarity as well as the resulting solubility of the P3HT:PCBM blend. Trace amount of nitrobenzene favoured the formation of better organised P3HT domains, as evident from conductive AFM, tapping mode AFM and surface, and cross-sectional SEM analysis. The higher interfacial surface area thus generated produced cells with high efficiency. But, an increase in the nitrobenzene composition leads to a decrease in cell performance, which is due to the formation of an active layer with larger size polymer domain networks with poor charge separation possibility.

Thomas, Ajith [Centre for Nano-Bio-Polymer Science and Technology, Department of Physics, St. Thomas College, Pala, Kerala 686574 (India); Research and Development Centre, Bharathiar University, Coimbatore, Tamilnadu 641046 (India); Elsa Tom, Anju; Ison, V. V., E-mail: isonvv@yahoo.in, E-mail: praveen@materials.iisc.ernet.in [Centre for Nano-Bio-Polymer Science and Technology, Department of Physics, St. Thomas College, Pala, Kerala 686574 (India); Rao, Arun D.; Varman, K. Arul; Ranjith, K.; Ramamurthy, Praveen C., E-mail: isonvv@yahoo.in, E-mail: praveen@materials.iisc.ernet.in [Department of Materials Engineering, Indian Institute of Science Bangalore, Karnataka 560012 (India); Vinayakan, R. [Department of Chemistry, SVR NSS College Vazhoor, Kerala 686505 (India)

2014-03-14

8

Studies on morphology and cytochemistry in blood cells of ayu Plecoglossus altivelis altivelis.  

PubMed

Peripheral blood cells from ayu, Plecoglossus altivelis altivelis, were separated using a density gradient. Blood cells were then smeared using Shandon Cytospin and subjected to cytochemical staining. Blood cells were categorized based on morphological and cytochemical characteristics, and the density fractionation range and nucleus area/cell area ratio were observed. Lymphocytes are distinguished from neutrophils by their basophilic cytoplasm and Golgi-like field. The features of chromatin in thrombocytes are different from those of lymphocytes or neutrophils, but some small neutrophils have similar chromatin. Therefore, it is necessary to perform peroxidase staining to distinguish small neutrophils from thrombocytes. Basophils have large basophilic granules in cytoplasm. Based on density fractionation of blood cells, thrombocytes in the low-density area were separated from other blood cells. Identification of peripheral blood cells from ayu was possible with these staining methods. Monocytes/macrophages from spleen are specifically positive for esterase staining by ?-naphthyl butyrate. As a result, thrombocytes, lymphocytes, neutrophils, basophils and monocytes/macrophages were identified in smears from peripheral blood or spleen tissue. In this paper, we confirmed that the peripheral blood corpuscles of ayu are able to be identified using the present staining methods. PMID:24476851

Nakada, Kojin; Fujisawa, Kuniyasu; Horiuchi, Hiroyuki; Furusawa, Shuichi

2014-05-01

9

Morphological studies of peripheral blood cells of the Chinese sturgeon, Acipenser sinensis  

Microsoft Academic Search

The peripheral blood cells of one-year-old Chinese sturgeon (Acipenser sinensis) have been studied by light microscopy and transmission electron microscopy. The erythrocyte count was 84.86 × 104 cell mm?3 in the peripheral blood of the fish and that of leukocytes was 2.24 × 104 cell mm?3. The erythrocytes and four main types of leucocyte—thrombocytes, lymphocytes, granulocytes (including neutrophils and eosinophils),\\u000a and monocytes, were identified in the peripheral blood.

Gao Zexia; Wang Weimin; Yang Yi; Khalid Abbas; Li Dapeng; Zou Guiwei; James S. Diana

2007-01-01

10

Comparison of cell viability and morphology of a human osteoblast-like cell line (SaOS-2) seeded on various bone substitute materials: An in vitro study  

PubMed Central

Background: Many studies have shown favorable results following the use of different bone graft materials. The aim of the present study was to evaluate the biocompatibility of four different bone graft materials regarding cell viability and morphology of Human osteoblast-like cells (SaOS-2) in vitro. Materials and Methods: The effects of Bio-Oss®, Tutodent®, Osteon®, and Cerasorb® were studied on the human osteoblast-like cell line to evaluate various parameters. Human osteoblast-like cells were seeded onto the mentioned bone substitute materials (BSMs). Cell differentiation; cell viability and alkaline phosphatase (ALP) activity of the seeded cells were evaluated by means of scanning electron microscopy, cell viability test and phase contrast microscopy Analysis of variance (ANOVA). Tamhane's post-hoc, Kruskal-Wallis Test, and Dunn's Test were used. The results were considered to be statistically significant at P<0.05. Results: The control group (SaOS-2 cells which were incubated in Dulbecco Modified Eagle Medium without any kind of bone graft materials) had the highest level of cell viability (P<0.001), followed by Tutodent®, Osteon®, Cerasorb®, and Bio-Oss®. There was no significant difference in MTT assay results between Tutodent® and the control group (P=0.032). All tested bone graft materials showed significantly higher ALP activity than the control (P<0.001). The Tutodent® group showed the best cell growth among all experimental groups, followed by the Osteon® group. The former had a higher spindle-like morphology with good attachment to the surface. Cells cultivated on the surfaces of the Cerasorb® and Bio-Oss® granules had more round morphologies. Conclusion: This in vitro study demonstrated that all tested BSMs can provide good cell differentiation but a lower rate of proliferation. PMID:22363369

Ayobian-Markazi, Nader; Fourootan, T.; Kharazifar, M. J.

2012-01-01

11

Plastic solar cell interface and morphological characterization  

NASA Astrophysics Data System (ADS)

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

Guralnick, Brett W.

12

Isolation of Mesophyll Cells and Bundle Sheath Cells from Digitaria sanguinalis (L.) Scop. Leaves and a Scanning Microscopy Study of the Internal Leaf Cell Morphology.  

PubMed

A technique is described for the separation of mesophyll and bundle sheath cells from Digitaria sanguinalis leaves and evidence for separation is given with light and scanning electron micrographs. Gentle grinding of fully differentiated leaves in a mortar releases mesophyll cells which are isolated on nylon nets by filtration. More extensive grinding of the remaining tissue yields bundle sheath strands which are isolated by filtration with stainless steel sieves and nylon nets. Further grinding of bundle sheath strands in a tissue homogenizer releases bundle sheath cells which are collected on nylon nets. Percentage of purity derived from cell counts and yield data on a chlorophyll basis are given.The internal leaf cell morphology is presented in scanning electron micrographs and compared with light micrographs of fully-differentiated D. sanguinalis leaves. In leaves of plants which possess the C(4)-dicarboxylic acid cycle of photosynthesis, the relationship of leaf morphology to photosynthesis in mesophyll and bundle sheath cells is considered, and the hypothesis is presented that as atmospheric CO(2) enters a leaf about 85% is fixed by the C(4)-dicarboxylic acid cycle in the mesophyll cells and 10 to 15% is fixed by the reductive pentose phosphate cycle in the bundle sheath cells.A technique also is given for the isolation of mesophyll cells from spinach leaves. PMID:16657571

Edwards, G E; Black, C C

1971-01-01

13

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

PubMed Central

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

2014-01-01

14

Heterogeneity in polymer solar cells: local morphology and performance in organic photovoltaics studied with scanning probe microscopy.  

PubMed

The use of organic photovoltaics (OPVs) could reduce production costs for solar cells because these materials are solution processable and can be manufactured by roll-to-roll printing. The nanoscale texture, or film morphology, of the donor/acceptor blends used in most OPVs is a critical variable that can dominate both the performance of new materials being optimized in the lab and efforts to move from laboratory-scale to factory-scale production. Although efficiencies of organic solar cells have improved significantly in recent years, progress in morphology optimization still occurs largely by trial and error, in part because much of our basic understanding of how nanoscale morphology affects the optoelectronic properties of these heterogeneous organic semiconductor films has to be inferred indirectly from macroscopic measurements. In this Account, we review the importance of nanoscale morphology in organic semiconductors and the use of electrical scanning probe microscopy techniques to directly probe the local optoelectronic properties of OPV devices. We have observed local heterogeneity of electronic properties and performance in a wide range of systems, including model polymer-fullerene blends such as poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM), newer polyfluorene copolymer-PCBM blends, and even all polymer donor-acceptor blends. The observed heterogeneity in local photocurrent poses important questions, chiefly what information is contained and what is lost when using average values obtained from conventional measurements on macroscopic devices and bulk samples? We show that in many cases OPVs are best thought of as a collection of nanoscopic photodiodes connected in parallel, each with their own morphological and therefore electronic and optical properties. This local heterogeneity forces us to carefully consider the adequacy of describing OPVs solely by "average" properties such as the bulk carrier mobility. Characterizing this local heterogeneity in the morphology of an OPV and the consequent variations in local performance is vital to understanding OPV operation. PMID:20143815

Groves, Chris; Reid, Obadiah G; Ginger, David S

2010-05-18

15

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

PubMed

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

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

1991-01-01

16

Phase diagrams and morphological evolution in wrapping of rod-shaped elastic nanoparticles by cell membrane: A two-dimensional study  

NASA Astrophysics Data System (ADS)

A fundamental understanding of cell-nanomaterial interaction is essential for biomedical diagnostics, therapeutics, and nanotoxicity. Here, we perform a theoretical analysis to investigate the phase diagram and morphological evolution of an elastic rod-shaped nanoparticle wrapped by a lipid membrane in two dimensions. We show that there exist five possible wrapping phases based on the stability of full wrapping, partial wrapping, and no wrapping states. The wrapping phases depend on the shape and size of the particle, adhesion energy, membrane tension, and bending rigidity ratio between the particle and membrane. While symmetric morphologies are observed in the early and late stages of wrapping, in between a soft rod-shaped nanoparticle undergoes a dramatic symmetry breaking morphological change while stiff and rigid nanoparticles experience a sharp reorientation. These results are of interest to the study of a range of phenomena including viral budding, exocytosis, as well as endocytosis or phagocytosis of elastic particles into cells.

Yi, Xin; Gao, Huajian

2014-06-01

17

Morphologic studies in the skeletal dysplasias.  

PubMed Central

Considerable progress has been made in the delineation of the genetic skeletal dysplasias, a heterogeneous group of disorders, that consist of over 80 distinct conditions. Morphologic studies have added a further dimension to the delineation of these conditions, their diagnosis, and the investigation of their pathogenetic mechanisms. In certain diseases, the morphologic alterations are characteristic and pathognomonic. In others only nonspecific alterations are observed, whereas in still other disorders growth-plate structure is essentially normal. Histologic, histochemical, and electronmicroscopic studies of growth-plate cartilage have provided new insights into the complexity of morphogenetic events in normal growth through the demonstration of morphologic defects in the genetic disorders of skeletal growth. As yet, very little is known of the biochemical abnormalities underlying the morphologic abnormalities. However, the great variety of morphologic findings points to a number of different pathogenetic defects in the synthesis, release, and assembly of connective tissue macromolecules and in the cells involved in growth-plate metabolism. Images Figure 4 Figure 8 Figure 5 Figure 7 Figure 10 Figure 6 Figure 9 Figure 1 Figure 3 Figure 2 PMID:474720

Sillence, D. O.; Horton, W. A.; Rimoin, D. L.

1979-01-01

18

Topography and morphology of retinal ganglion cells in Falconiforms: a study on predatory and carrion-eating birds.  

PubMed

The topographic distribution of retinal ganglion cells and their cell body size have been studied in five Falconiform species, including predatory (chilean eagle Buteo fuscenses australis, and sparrow hawk Falco sparverius) and carrion-eating (chimango caracara Milvago chimango; condor Vultur gryphus, and black vulture Coragyps atratus) birds. All these species had a well defined nasal fovea and a horizontal streak. Instead of a temporal fovea as in eagles and hawks, an afoveate temporal area is present in chimango, condor, and vulture. The highest ganglion cell density was found in the nasal fovea of Falco and Buteo with 65,000 and 62,000 cells/mm2, respectively. A negative correlation between ganglion cell density and cell body size was found in all the species studied. The specializations of the temporal retina showed a rather homogenous population of medium sized neurons, while the nasal foveas showed a homogeneous population of smaller ganglion cells. Finally, the peripheral retina showed a heterogeneous population of large, medium, and small ganglion cells. Predatory behavior appears to be closely related to foveal specializations, and is best exemplified in the eagle and hawk and to a lesser extent in the chimango. PMID:2012314

Inzunza, O; Bravo, H; Smith, R L; Angel, M

1991-02-01

19

On-line study of fungal morphology during submerged growth in a small flow-through cell.  

PubMed

A flow-through cell is designed to measure the growth kinetics of hyphae of Aspergillus oryzae grown submerged in a well controlled environment. The different stages of the growth process are characterized, from the spore to the fully developed hyphal element with up to 60 branches and a total length lt up to 10,000 micrometer. Spore swelling is found to occur without change in the form of the spore (circularity index constant at about 1.06) and the spore volume probably increases exponentially. The germ tube appears after about 4 h. The branching frequency and the rate of germ tube extension is determined. After about 10 h growth at a glucose concentration of 250 mg L-1, 6-7 branches have been set, and both the total hyphal length lt and the number of tips increase exponentially with time. The specific growth rate of the hyphae is 0. 33 h-1 while the average rate of the extension of the growing tips approaches 55 micrometer h-1. The growth kinetics for all the branches on the main hypha have also been found. The main hypha and all the branches grow at a rate which can be modeled by saturation kinetics with respect to the branch length and with nearly equal final tip speeds (160 micrometer h-1). Branches set near the apical tip of the main hypha attain their final tip speed in the shortest time, i.e., the value of the saturation parameter is small. Finally, the influence of substrate (glucose) concentration cs on the values of the morphological parameters has been determined. It is found that saturation type kinetics can be used to describe the influence of cs on the growth. Experiments with recirculation of effluent from the cell back to the inlet strongly suggest that the fungus secretes an inducer for growth and branching. PMID:10099291

Spohr, A; Dam-Mikkelsen, C; Carlsen, M; Nielsen, J; Villadsen, J

1998-06-01

20

Cryptococcal Cell Morphology Affects Host Cell Interactions and Pathogenicity  

PubMed Central

Cryptococcus neoformans is a common life-threatening human fungal pathogen. The size of cryptococcal cells is typically 5 to 10 µm. Cell enlargement was observed in vivo, producing cells up to 100 µm. These morphological changes in cell size affected pathogenicity via reducing phagocytosis by host mononuclear cells, increasing resistance to oxidative and nitrosative stress, and correlated with reduced penetration of the central nervous system. Cell enlargement was stimulated by coinfection with strains of opposite mating type, and ste3a? pheromone receptor mutant strains had reduced cell enlargement. Finally, analysis of DNA content in this novel cell type revealed that these enlarged cells were polyploid, uninucleate, and produced daughter cells in vivo. These results describe a novel mechanism by which C. neoformans evades host phagocytosis to allow survival of a subset of the population at early stages of infection. Thus, morphological changes play unique and specialized roles during infection. PMID:20585559

Nielsen, Judith N.; Charlier, Caroline; Baltes, Nicholas J.; Chrétien, Fabrice; Heitman, Joseph; Dromer, Françoise; Nielsen, Kirsten

2010-01-01

21

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

22

Morphological study of penumbral formation  

NASA Astrophysics Data System (ADS)

Penumbrae are known to be areas of mainly horizontal magnetic field surrounding umbrae of relatively large and mature sunspots. In this paper, we observationally studied the formation of penumbrae in NOAA 10978, where several penumbral formations were observed in G-band images of the Solar Optical Telescope on board Hinode. Thanks to the continuous observation by Hinode, we could morphologically follow the evolution of sunspots and found that there are several paths to the penumbral formation: (1) active accumulation of magnetic flux, (2) rapid emergence of magnetic field, and (3) appearance of twisted or rotating magnetic tubes. In all of these cases, magnetic fields are expected to sustain high inclination at the edges of flux tube concentration longer than the characteristic growth time of downward magnetic pumping.

Kitai, Reizaburo; Watanabe, Hiroko; Otsuji, Ken'ichi

2014-12-01

23

Systematic investigation of structural and morphological studies on doped TiO2 nanoparticles for solar cell applications  

NASA Astrophysics Data System (ADS)

Optical, structural and thermal properties of the doped with different ions (transition metals, other metals or post transition metals, non-metals, alkali metals and lanthanides) in TiO2 nanocrystals were investigated. The doped nanoparticles were synthesized by modified chemical method. Ethanol-deionised water mixer (20:1) was used as solvent for synthesize of the undoped and doped TiO2 nanoparticles. Systematic studies on structural and morphological changes by thermal treatment on TiO2 were examined. It has been observed that with Eu and Al doping TiO2, the phase transition temperature for anatase to rutile phase increased. Blue and red shifting absorptions were observed for doped TiO2 in visible region. Among the dopant, significant blue shift was obtained for Cu, Cd, Ag, Y, Ce and In doped TiO2 and red shift was obtained for Zr, Sm, Al, Na, S, Fe, Ni, Eu and Gd doped TiO2 nanoparticles.

Murugadoss, G.; Jayavel, R.; Rajesh Kumar, M.

2014-12-01

24

BLOOD CELLS MORPHOLOGY OF THE SNAIL HELIX ASPERSA MAXIMA (HELICIDAE)  

Microsoft Academic Search

Morphological characters of haemocytes and seasonal changes in se- lected blood indices were studied in Helix aspersa maxima. Two types of haemocytes were identified: I (Ia and Ib) and II. Spherical type I haemocytes (ca. 93 %) are cells capable of spreading on the substratum and forming numerous pseudopodia. Subtypes Ia and Ib are most probably two different development stages

ANNA ADAMOWICZ; MAGDALENA BOLACZEK

25

Spindle cell morphology is related to poor prognosis in vulvar squamous cell carcinoma  

PubMed Central

Background: Vulvar cancer is the fourth most common gynaecological malignancy, with an annual incidence of 2 out of 100?000 women. Although most cases of early stage vulvar cancer have a good prognosis, recurrence and rapid tumour progression can occur. We investigated the prevalence of spindle cell morphology in vulvar cancer and its association with survival. Methods: This retrospective cohort study included 108 patients with primary vulvar squamous cell carcinoma who were treated at the Leiden University Medical Center during 2000–2009. Paraffin-embedded tissue was examined for the presence of spindle cell morphology. Survival and histology data were compared between cases with spindle and without spindle cell morphology. Results: Twenty-two (20%) tumours showed spindle cells infiltrating the stromal tissue. All spindle cell tumours were human papillomavirus (HPV) negative. Spindle cell morphology was strongly associated with poor prognosis and with a high risk of lymph node involvement at the time of diagnosis (relative risk 2.26 (95% CI 1.47–3.47)). Five-year disease-specific survival was lower in patients with vs without spindle cell morphology (45.2% vs 79.7%, respectively; P=0.00057). Conclusion: Vulvar spindle cell morphology occurs frequently and seems to develop through the non-HPV pathway. It is associated with a worse prognosis than conventional vulvar squamous cell carcinoma. PMID:24064972

Trietsch, M D; Peters, A A W; Gaarenstroom, K N; van Koningsbrugge, S H L; ter Haar, N T; Osse, E M; Halbesma, N; Fleuren, G J

2013-01-01

26

Cell Reproduction and Morphological Changes in Mycoplasma capricolum  

Microsoft Academic Search

The cell reproduction of Mycoplasma capricolum was studied. The velocity of DNA replication fork progres- sion was about 6 kb\\/min, which is 10 times slower than that of Escherichia coli. The time required for one round of DNA replication accorded with the doubling time. The origin\\/terminus ratio was 2.0. M. capricolum cell morphology was classified into two types, rod and

SHINTARO SETO; MAKOTO MIYATA

1998-01-01

27

Morphological effect of oscillating magnetic nanoparticles in killing tumor cells.  

PubMed

Forced oscillation of spherical and rod-shaped iron oxide magnetic nanoparticles (MNPs) via low-power and low-frequency alternating magnetic field (AMF) was firstly used to kill cancer cells in vitro. After being loaded by human cervical cancer cells line (HeLa) and then exposed to a 35-kHz AMF, MNPs mechanically damaged cell membranes and cytoplasm, decreasing the cell viability. It was found that the concentration and morphology of the MNPs significantly influenced the cell-killing efficiency of oscillating MNPs. In this preliminary study, when HeLa cells were pre-incubated with 100 ?g/mL rod-shaped MNPs (rMNP, length of 200?±?50 nm and diameter of 50 to 120 nm) for 20 h, MTT assay proved that the cell viability decreased by 30.9% after being exposed to AMF for 2 h, while the cell viability decreased by 11.7% if spherical MNPs (sMNP, diameter of 200?±?50 nm) were used for investigation. Furthermore, the morphological effect of MNPs on cell viability was confirmed by trypan blue assay: 39.5% rMNP-loaded cells and 15.1% sMNP-loaded cells were stained after being exposed to AMF for 2 h. It was also interesting to find that killing tumor cells at either higher (500 ?g/mL) or lower (20 ?g/mL) concentration of MNPs was less efficient than that achieved at 100 ?g/mL concentration. In conclusion, the relatively asymmetric morphological rod-shaped MNPs can kill cancer cells more effectively than spherical MNPs when being exposed to AMF by virtue of their mechanical oscillations. PMID:24872797

Cheng, Dengfeng; Li, Xiao; Zhang, Guoxin; Shi, Hongcheng

2014-01-01

28

Morphological Studies of Bell Pepper Germplasm  

Microsoft Academic Search

Morphological characterization of bell pepper (Capsicum annuum L. var. grosssum Sendt.) germplasm is a prerequisite in a crop improvement program. The study was conducted during 2007 and 2008 at the vegetable experimental farm of the CSK Himachal Pradesh Agricultural University, Palampur, Himachal Pradesh, India, to study morphological traits of bell pepper genotypes which include the parents ‘Kandaghat Selection’, ‘EC-464115’, ‘EC-464107’,

Sonia Sood; Naveen Kumar

2011-01-01

29

Morphology study in block copolymer electrolytes  

NASA Astrophysics Data System (ADS)

Poly(styrene-b-ethylene oxide)/lithium bis(trifluoromethane)sulfonimide (SEO/LiTFSI) is of interest in battery applications since the doped PEO phase can conduct ions and the glassy PS phase can prevent dendrite growth upon recharging. It is believed that the LiTFSI molecules are localized in the PEO microphases. Previous studies have shown that highly conducting electrolytes can be made from symmetric SEO copolymers. The purpose of this study is to explore the conductivity of asymmetric SEO copolymer systems doped with LiTFSI. Our studies encompass both neat asymmetric SEO copolymers and SEO copolymers blended with PS homopolymers to separate the effects of architecture of the copolymer molecules and morphology adopted by the system in the melt state. Conductivity is measured by AC impedance, morphology is determined by small angle X-ray scattering, and crystallinity of the PEO chains is determined by differential scanning calorimetry. All samples were prepared in hermetically sealed sample cells in an Argon glovebox.

Mullin, Scott; Wanakule, Nisita; Balsara, Nitash

2008-03-01

30

Further morphological studies of QSOs  

NASA Technical Reports Server (NTRS)

Results are presented of optical mapping of 29 QSOs, together with results of VLA observations of 16 of the optically observed objects. Principal results are that QSOs to z = 0.45 have extended nebulosity, the average ratio of nuclear to fuzz luminosity, corrected for resolution, is about 0.5, some 8 times higher than Seyfert I values, the average fuzz luminosity is -21.5, fainter than giant ellipticals, and fuzz morphology does not resemble E or S galaxies, but is very similar to Seyfert I's to similar luminosity limits. In some cases, indications of spiral structure are seen, and a large fraction of asymmetrical morphology is noted. In the QSO 0241 + 622, steep spectrum radio emission is found displaced from the central source exactly along the minor optical axis.

Hutchings, J. B.; Campbell, B.; Gower, A. C.; Crampton, D.; Morris, S. C.

1982-01-01

31

Localization of antigen on lymph node dendritic cells after exposure to the contact sensitizer fluorescein isothiocyanate. Functional and morphological studies  

PubMed Central

We have examined the cells involved in the development of contact sensitivity to FITC in CBA mice. After skin painting with antigen, the number of dendritic cells (DC) in the draining lymph nodes increased by 30 min, was maximal at 48 h, and returned to normal by 6 d. Derivation of some DC from Langerhans' cells of the skin was indicated from the presence of Birbeck granules observed in some DC isolated 24 h after skin painting. The DC acquired FITC and by 8 h there were two populations, one highly fluorescent and the other less fluorescent. The highly fluorescent cells were present between 8 h and 3 d after sensitization, and during this period the DC were potent at initiating primary proliferative responses of normal syngeneic T lymphocytes in vitro. Between days 3 and 5 the numbers of lymphocytes in the draining lymph node increased. During this period purified T lymphocytes did not express detectable levels of antigen, but enriched B cell populations expressed antigen transiently on day 1, 2, or 3 after exposure to antigen. The results showed that, during a 3-d period after exposure to antigen, DC expressed antigen and stimulated T cell proliferation. We speculate that low amounts of FITC binding selectively to veiled cells or lymph node DC in the first hours after exposure to antigen are not immunogenic but that Langerhans' cells acquire high levels of antigen, enter the nodes, and initiate immune responses. PMID:3119761

1987-01-01

32

Morphologic spectrum, immunohistochemical analysis, and clinical features of a series of granular cell tumors of soft tissues: a study from a tertiary referral cancer center.  

PubMed

A granular cell tumor (GCT) is relatively uncommon and objectively diagnosed with neural markers on immunohistochemistry (IHC). Recent studies have described additional markers for a GCT. Herein, we present morphologic spectrum of 12 GCTs of soft tissues and skin, including 10 benign and 2 malignant subtypes with an optimal diagnostic IHC panel. Eleven cases occurred in women and 1 in a man, with a mean age of 45.5 years. Six cases occurred in soft tissues and skin of extremities, 4 in the breast soft tissues, and 1 case each in the back and preauricular region, respectively. Cytologic smears in 2 cases displayed polygonal cells with abundant, eosinophilic, granular cytoplasm. On histopathology, all cases invariably revealed a nonencapsulated infiltrating tumor comprising groups and nests of granular cells with vesicular nuclei. In 5 cases, granular cells were noted in close proximity to the nerves. Two malignant GCTs revealed necrosis, mitoses, and nuclear atypia. Immunohistochemistry in 10 cases (83.3%) showed diffuse S-100 positivity in all 7 benign and 2 malignant cases: cytoplasmic CD68 positivity (all 10 cases) and membranous vimentin staining (all 4 cases). Inhibin showed cytoplasmic positivity in 3 of 6 cases. A single malignant GCT showed focal desmin reactivity. All were surgically managed. A GCT is a discrete tumor entity and can be identified from other granular lesions by its proximity to nerves and objective identification with diffuse S-100 positivity, CD68 positivity, and membranous vimentin positivity that form an optimal IHC panel in limited resource settings, irrespective of benign or malignant types. PMID:20471560

Rekhi, Bharat; Jambhekar, Nirmala A

2010-06-01

33

[Morphological studies of human gallbladder].  

PubMed

I tried to make it clear three dimensional picture of the smooth muscle of the human gallbladder at first, and found a connection between the smooth muscle and the autonomic nerves in the wall. At autopsy the gallbladder without lesion was collected from 15 males and 7 females died of apoplexy, head injury or myocardial infarction. These material was fixed 10% neural formalin, impregnated into Masson Trichrome for smooth muscle, and modified Golgi method for nerve fivers, embeded in celloidin. I laid a picture after another after tracing serial tangential section of 8 micron by using camera lucida, and made three dimensional picture. In autonomic nerve in the wall three dimensional sections of 100-150 micron were made and observed with light microscope. Three dimensional muscle structure showed monounit structure, having meshwork structure from mucosal area to serous one. It was gratified the condition of the gallbladder contraction to illustrate a series of connection from mucosal aspect to serous one. Many fine nerve fivers were found forming plexuses in the subserous layer, muscular layer and mucosa. There was close relationship between smooth muscle and intramural nerve fibers, which especially distributed into meshwork structure of muscle. I could find morphological relation among the layers, such as three main plexuses. It was suggested that subserous plexus had extrinsic nature. PMID:4087619

Sugai, M

1985-04-01

34

Morphological study of 5-HT neurons and astroglial cells on brain of adult rats perinatal or chronically exposed to 2,4-dichlorophenoxyacetic acid.  

PubMed

2,4-D is a chlorophenoxyherbicide used worldwide. We have studied the morphological alterations of 5-HT neurons and glial cells in the mesencephalic nuclei of adult rats exposed to 2,4-D both perinatally (during pregnancy and lactation) and chronically (during pregnancy, lactation and after weaning) with quantitative methods. Pregnant rats were daily exposed to 70 mg/kg of 2,4-D from gestation day (GD) 16 to post-natal day (PND) 23 through diet. After weaning, pups were assigned to one of two sub-groups: T1 (fed with untreated diet until PND 90) and T2 (maintained with 2,4-D diet until PND 90). Brain sections were immunocytochemically stained using polyclonal anti-5-HT, anti-GFAP and anti-S-100 protein antibodies as cells markers. 2,4-D exposure during pregnancy and lactancy (T1 group) produced an increase in 5-HT neuronal area and immunoreactivity (IR) in the mesencephalic nuclei studied. However, with the chronical 2,4-D exposure (T2 group) only the 5-HT neuronal area from the dorsal raphe nucleus (DRN) was increased, suggesting an adaptable response of 5-HT neurons in median raphe nucleus (MRN). The presence of reactive astrocytes in mesencephalic nuclei and in hippocampus were also different for the two 2,4-D exposure designs, showing the existence of a correspondence between neuronal changes and astrogliosis. Results support evidences that 2,4-D alters the serotoninergic system and that 5-HT neurons of each mesencephalic nuclei show different responses to the 2,4-D exposure designs which are parallel to astrogliosis. PMID:11829407

Garcia, G; Tagliaferro, P; Bortolozzi, A; Madariaga, M J; Brusco, A; Evangelista de Duffard, A M; Duffard, R; Saavedra, J P

2001-12-01

35

Budded karyoplasts from multinucleated fibroblast cells contain centrosomes and change their morphology to mitotic cells.  

PubMed

Cell changes to accelerated rates of growth are determined by random, new gene mutations that have their origin in vitro in a morphologically visible process of cell alterations. It is a continuous process that, step by step, transforms the normal cell into extended life (EL) cells. These latter cells with limited life spans can further transform to immortalized cells (i.e., cell lines) by the same sequence of morphological cell changes. In contrast to human epithelial cells, fibroblasts in culture have not given rise spontaneously to EL cells. Therefore, it was assumed that some of the cell changes (i.e., cell indicators of the process of transformation) might not be present in near senescent fibroblast cell cultures. As a positive control to normal fibroblast expansion to senescence, the same cells were stressed by inadequate nutrition and confluence. Another positive control was cell indicators induced by SV40 infections. The consecutive sequence of the cell indicators in the transformation process reported previously were: (1) large polyploid cells with nuclei that contained more than two genomes, (2) fragmentation/amitosis of the polyploid nuclei to bi- and multinucleated cells (MNCs), and (3) nuclear budding (i.e., karyoplasts) from MNCs that gave rise to EL cell colonies with various longevities beyond the senescent phase. The present study shows that MNCs and karyoplasts were present in the near-senescent fibroblast cell cultures. Furthermore, new data on the following aspect of the cell transformation process are presented: (1) association of the nuclear fragmentation process with death of cells, (2) cytological markers that distinguish between fragmentation-MNCs versus MNCs from cell fusion, (3) cytological changes of karyoplasts that go through mitotic division to produce daughter cells, and (4) presence of two centrosomes (spindle polar bodies) in the budded karyoplasts. These new findings are discussed in regard to the nuclear fragmentation process in polyploid cells which gives rise to smaller, viable nuclei in MNCs with reduced numbers of whole genomes. PMID:16316754

Walen, Kirsten H

2005-12-01

36

Geometric control of human stem cell morphology and differentiationw Leo Q. Wan,a  

E-print Network

During tissue morphogenesis, stem cells and progenitor cells migrate, proliferate, and differentiateGeometric control of human stem cell morphology and differentiationw Leo Q. Wan,a Sylvia M. Kang. In this study, we controlled the organization of human adipose derived stem cells using micro

Linhardt, Robert J.

37

Stem Cell Niche Structure as an Inherent Cause of Undulating Epithelial Morphologies  

PubMed Central

The spatial organization of stem cells into a niche is a key factor for growth and continual tissue renewal during development, sustenance, and regeneration. Stratified epithelia serve as a great context to study the spatial aspects of the stem cell niche and cell lineages by organizing into layers of different cell types. Several types of stratified epithelia develop morphologies with advantageous, protruding structures where stem cells reside, such as rete pegs and palisades of Vogt. Here, multistage, spatial cell lineage models for epithelial stratification are used to study how the stem cell niche influences epithelial morphologies. When the stem cell niche forms along a rigid basal lamina, relatively regular morphologies are maintained. In contrast, stem cell niche formation along a free-moving basal lamina may prompt distorted epithelial morphologies with stem cells accumulating at the tips of fingerlike structures that form. The correspondence between our simulated morphologies and developmental stages of the human epidermis is also explored. Overall, our work provides an understanding of how stratified epithelia may attain distorted morphologies and sheds light on the importance of the spatial aspects of the stem cell niche. PMID:23332076

Ovadia, Jeremy; Nie, Qing

2013-01-01

38

Segmental tandem triplication of the MLL gene in an intravascular large B-cell lymphoma with multisystem involvement: a comprehensive morphologic, immunophenotypic, cytogenetic, and molecular cytogenetic antemortem study.  

PubMed

An association between intravascular large B-cell lymphoma (IVLBCL) and the mixed lineage leukemia (MLL) gene has never been demonstrated. Here, we report an IVLBCL in a 47-year-old Asian man. Morphologically, the atypical lymphoid infiltrate was entirely confined in the lumina of capillaries, small vessels, and sinusoidal space. Within the kidney, the neoplastic lymphoid cells exhibited both the glomerular and peritubular capillary distribution pattern. Conventional cytogenetic analysis from the bone marrow aspirates displayed a complex karyotype, with a notable triple tandem repeat at band segment q22-q25 of chromosome 11. Fluorescence in situ hybridization with an MLL probe set, performed on both interphase cells and metaphase spreads, confirmed the presence of 3 copies of the MLL gene on the derivative chromosome 11. From this finding and 3 other IVLBCL cases reported in the literature, we conclude that MLL may play an important role in the lymphomagenesis of IVLBCL at least in a subset of cases. PMID:19722759

Deisch, Jeremy; Fuda, Franklin Buddy; Chen, Weina; Karandikar, Nitin; Arbini, Arnaldo A; Zhou, Xin J; Wang, Huan-You

2009-09-01

39

Correlating the morphological and light scattering properties of biological cells  

NASA Astrophysics Data System (ADS)

The scattered light pattern from a biological cell is greatly influenced by the internal structure and optical properties of the cell. This research project examines the relationships between the morphological and scattering properties of biological cells through numerical simulations. The mains goals are: (1) to develop a procedure to analytically model biological cells, (2) to quantitatively study the effects of a range of cell characteristics on the features of the light scattering patterns, and (3) to classify cells based on the features of their light scattering patterns. A procedure to create an analytical cell model was developed which extracted structural information from the confocal microscopic images of cells and allowed for the alteration of the cell structure in a controlled and systematic way. The influence of cell surface roughness, nuclear size, and mitochondrial volume density, spatial distribution, size and shape on the light scattering patterns was studied through numerical simulations of light scattering using the Discrete Dipole Approximation. It was found that the light scattering intensity in the scattering angle range of 25° to 45° responded to changes in the surface fluctuation of the cell and the range of 90° to 110° was well suited for characterization of mitochondrial density and nuclear size. A comparison of light scattering pattern analysis methods revealed that the angular distribution of the scattered light and Gabor filters were most helpful in differentiating between the cell characteristics. In addition, a measured increase in the Gabor energy of the light scattering patterns in response to an increase in the complexity of the cell models suggested that a complex nuclear structure and mitochondria should be included when modeling biological cells for light scattering simulations. Analysis of the scattering pattern features with Gabor filters resulted in discrimination of the cell models according to cell surface roughness, nuclear size, and mitochondrial volume density and size with over 90% classification accuracy. This study suggested the location of the scattering planes that are most relevant to researchers depending on the desired information about the cell and may provide a quantitative approach to cell discrimination with practical applications in flow cytometry for the diagnosis of diseases.

Moran, Marina

40

Morphology and vasoactive hormone profiles from endothelial cells derived from stem cells of different sources.  

PubMed

Endothelial cells form a highly specialised lining of all blood vessels where they provide an anti-thrombotic surface on the luminal side and protect the underlying vascular smooth muscle on the abluminal side. Specialised functions of endothelial cells include their unique ability to release vasoactive hormones and to morphologically adapt to complex shear stress. Stem cell derived-endothelial cells have a growing number of applications and will be critical in any organ regeneration programme. Generally endothelial cells are identified in stem cell studies by well-recognised markers such as CD31. However, the ability of stem cell-derived endothelial cells to release vasoactive hormones and align with shear stress has not been studied extensively. With this in mind, we have compared directly the ability of endothelial cells derived from a range of stem cell sources, including embryonic stem cells (hESC-EC) and adult progenitors in blood (blood out growth endothelial cells, BOEC) with those cultured from mature vessels, to release the vasoconstrictor peptide endothelin (ET)-1, the cardioprotective hormone prostacyclin, and to respond morphologically to conditions of complex shear stress. All endothelial cell types, except hESC-EC, released high and comparable levels of ET-1 and prostacyclin. Under static culture conditions all endothelial cell types, except for hESC-EC, had the typical cobblestone morphology whilst hESC-EC had an elongated phenotype. When cells were grown under shear stress endothelial cells from vessels (human aorta) or BOEC elongated and aligned in the direction of shear. By contrast hESC-EC did not align in the direction of shear stress. These observations show key differences in endothelial cells derived from embryonic stem cells versus those from blood progenitor cells, and that BOEC are more similar than hESC-EC to endothelial cells from vessels. This may be advantageous in some settings particularly where an in vitro test bed is required. However, for other applications, because of low ET-1 release hESC-EC may prove to be protected from vascular inflammation. PMID:25449267

Reed, Daniel M; Foldes, Gabor; Kirkby, Nicholas S; Ahmetaj-Shala, Blerina; Mataragka, Stefania; Mohamed, Nura A; Francis, Catherine; Gara, Edit; Harding, Sian E; Mitchell, Jane A

2014-12-12

41

The Morphology and Intrinsic Excitability of Developing Mouse Retinal Ganglion Cells  

PubMed Central

The retinal ganglion cells (RGCs) have diverse morphology and physiology. Although some studies show that correlations between morphological properties and physiological properties exist in cat RGCs, these properties are much less distinct and their correlations are unknown in mouse RGCs. In this study, using three-dimensional digital neuron reconstruction, we systematically analyzed twelve morphological parameters of mouse RGCs as they developed in the first four postnatal weeks. The development of these parameters fell into three different patterns and suggested that contact from bipolar cells and eye opening might play important roles in RGC morphological development. Although there has been a general impression that the morphological parameters are not independent, such as RGCs with larger dendritic fields usually have longer but sparser dendrites, there was not systematic study and statistical analysis proving it. We used Pearson's correlation coefficients to determine the relationship among these morphological parameters and demonstrated that many morphological parameters showed high statistical correlation. In the same cells we also measured seven physiological parameters using whole-cell patch-clamp recording, focusing on intrinsic excitability. We previously reported the increase in intrinsic excitability in mouse RGCs during early postnatal development. Here we showed that strong correlations also existed among many physiological parameters that measure the intrinsic excitability. However, Pearson's correlation coefficient revealed very limited correlation across morphological and physiological parameters. In addition, principle component analysis failed to separate RGCs into clusters using combined morphological and physiological parameters. Therefore, despite strong correlations within the morphological parameters and within the physiological parameters, postnatal mouse RGCs had only limited correlation between morphology and physiology. This may be due to developmental immaturity, or to selection of parameters. PMID:21765913

Qu, Juan; Myhr, Karen L.

2011-01-01

42

A Study of the Effect of Heat-Treatment on the Morphology of Nafion Ionomer Dispersion for Use in the Passive Direct Methanol Fuel Cell (DMFC).  

PubMed

Aggregation in heat-treated Nafion ionomer dispersion and 117 membrane are investigated by 1H and 19F Nuclear Magnetic Resonance (NMR) spectra, spin-lattice relaxation time, and self-diffusion coefficient measurements. Results demonstrate that heat-treatment affects the average Nafion particle size in aqueous dispersions. Measurements on heat-treated Nafion 117 membrane show changes in the 1H isotropic chemical shift and no significant changes in ionic conductivity. Scanning electron microscopy (SEM) analysis of prepared cathode catalyst layer containing the heat-treated dispersions reveals that the surface of the electrode with the catalyst ink that has been pretreated at ca. 80 °C exhibits a compact and uniform morphology. The decrease of Nafion ionomer's size results in better contact between catalyst particles and electrolyte, higher electrochemically active surface area, as well as significant improvement in the DMFC's performance, as verified by electrochemical analysis and single cell evaluation. PMID:24958431

Yuan, Ting; Zhang, Haifeng; Zou, Zhiqing; Khatun, Sufia; Akins, Daniel; Adam, Yara; Suarez, Sophia

2012-01-01

43

A Study of the Effect of Heat-Treatment on the Morphology of Nafion Ionomer Dispersion for Use in the Passive Direct Methanol Fuel Cell (DMFC)  

PubMed Central

Aggregation in heat-treated Nafion ionomer dispersion and 117 membrane are investigated by 1H and 19F Nuclear Magnetic Resonance (NMR) spectra, spin-lattice relaxation time, and self-diffusion coefficient measurements. Results demonstrate that heat-treatment affects the average Nafion particle size in aqueous dispersions. Measurements on heat-treated Nafion 117 membrane show changes in the 1H isotropic chemical shift and no significant changes in ionic conductivity. Scanning electron microscopy (SEM) analysis of prepared cathode catalyst layer containing the heat-treated dispersions reveals that the surface of the electrode with the catalyst ink that has been pretreated at ca. 80 °C exhibits a compact and uniform morphology. The decrease of Nafion ionomer’s size results in better contact between catalyst particles and electrolyte, higher electrochemically active surface area, as well as significant improvement in the DMFC’s performance, as verified by electrochemical analysis and single cell evaluation. PMID:24958431

Yuan, Ting; Zhang, Haifeng; Zou, Zhiqing; Khatun, Sufia; Akins, Daniel; Adam, Yara; Suarez, Sophia

2012-01-01

44

Morphological study of the northern pike (Esox lucius) tongue.  

PubMed

The northern pike (Esox lucius) is a fresh water species belonging to the Esocidae family. It is a carnivorous fish feeding mostly on invertebrates and fishes. Due to the scantiness of relevant literature regarding the morphology of the tongue in fish we carried out this study with the aim of providing information on the dorsal surface morphology and histological structures of the tongue in E. lucius. The tongues of five E. lucius were examined using light- and scanning electron- microscopy (SEM) techniques. The SEM studies revealed the presence of numerous teeth, longitudinal mucosal strands and scattered taste buds spread on the tongue surface. Histological studies using hematoxylin and eosin and Masson's trichrome staining showed that the musculature was not visible in the tongue of E. lucius. The tongue is composed of mucosa, and submucosa supported by osteocartilagionous skeleton. The mucosa consists of several layers of unicellular mucous cells interrupted by numerous teeth. The derivation of teeth from the underlying bronchial skeleton was visible in longitudinal section. The scattered taste buds with a typical onion shape were also present. Overall, the morphological features of the E. lucius tongue together suggested its mechanical and sensory roles. The findings of this study together with morphological and physiological data from other fishes contribute to the knowledge of the nutrition and feeding behavior in aquaculture species. PMID:25205560

Sadeghinezhad, Javad; Rahmati-Holasoo, Hooman; Fayyaz, Sahel; Zargar, Ashkan

2014-09-10

45

Spatial and temporal changes in the morphology of preosteoblastic cells seeded on microstructured tantalum surfaces.  

PubMed

It has been widely reported that surface morphology on the micrometer scale affects cell function as well as cell shape. In this study, we have systematically compared the influence of 13 topographically micropatterned tantalum surfaces on the temporal development of morphology, including spreading, and length of preosteoblastic cells (MC3T3-E1). Cells were examined after 0.5, 1, 4, and 24 h on different Ta microstructures with vertical dimensions (heights) of 0.25 and 1.6 mum. Cell morphologies depended upon the underlying surface topography, and the length and spreading of cells varied as a function of time with regard to the two-dimensional pattern and vertical dimension of the structure. Microstructures of parallel grooves/ridges caused elongated cell growth after 1 and 4 h in comparison to a flat, nonstructured, reference surface. For microstructures consisting of pillars, cell spreading was found to depend on the distance between the pillars with one specific pillar structure exhibiting a decreased spreading combined with a radical change in morphology of the cells. Interestingly, this morphology on the particular pillar structure was associated with a markedly different distribution of the actin cytoskeleton. Our results provide a basis for further work toward topographical guiding of cell function. PMID:18465820

Justesen, J; Lorentzen, M; Andersen, L K; Hansen, O; Chevallier, J; Modin, C; Füchtbauer, A; Foss, M; Besenbacher, F; Duch, M; Pedersen, F S

2009-06-15

46

[A microscopic study of the comparative morphology of the retina].  

PubMed

The cytoarchitecture layers and sublayers of the retina in pike, frog and cat are essentially different. The sublayers of internal granular layers 6a, 6b, 6c, 6d in these species differ qualitatively and quantitatively. The dendrites of ganglion cells and branches of amacrine cells are greatly laminated in the frog retina due to a complex stratification of the inner plexiform layer (about 10 sublayers). In all the vertebrates studied the ganglion cells are of two main types; symmetrical and asymmetrical with many variations. Asymmetrical amacrine cells are found in the pike and frog retina. The existence of vertical branches of amacrine cells in the outer plexiform layer in the cat retina is confirmed. The morphological features of the retina are discussed from the view point of physiological facts. PMID:1207797

Shkol'nik-Iarros, E G; Podugol'nikova, T A; Diubina, A P

1975-01-01

47

Morphology and expression status investigations of specific surface markers on B-cell chronic lymphocytic leukemia cells.  

PubMed

The morphology of cells and expression status of specific surface markers [cluster of differentiation (CD)], such as CD5, CD19, CD20, CD38, and CD45, have long been considered as the essential indicators for the diagnosis and prognosis of B-cell chronic lymphocytic leukemia (B-CLL). Clinically, it is difficult to simultaneously obtain cell morphology and distribution of surface markers with flow cytometry, especially for some surrogate markers such as CD38. Here, as an alternative and complementary prognostic method, fluorescence microscopy and image processing method are introduced to directly visualize the cells from patients and to quantitatively determine the expression status of surface markers. In this study, the morphological parameters of B-CLL cells were measured to establish the correlation between the cellular morphology and the surface marker expression. It was clear that the CD38+ and CD38- B-CLL cells from the same CD38+ patients had hardly any size differences; however, an increase in perimeter was observed for CD38- patients. Moreover, the expression level of the receptors on the cell was independent of the cell size. There was no evidence showing that the expression intensities of CD19 and CD38 were related to each other for the CD38+ B-CLL cells. On the same cells, CD5 was more selectively expressed on the cell membrane; however, the expression patterns suggested that the cell membrane of CD38- B-CLL cells contained the least expression level of CD19. PMID:23963997

Niu, Suli; Chan, Ryan; Berini, Pierre; Wang, Chen; Zou, Shan

2013-11-01

48

The effects of morphology, confluency, and phenotype on whole-cell mechanical behavior.  

PubMed

Emerging evidence indicates that cellular mechanical behavior can be altered by disease, drug treatment, and mechanical loading. To effectively investigate how disease and mechanical or biochemical treatments influence cellular mechanical behavior, it is imperative to determine the source of large inter-cell differences in whole-cell mechanical behavior within a single cell line. In this study, we used the atomic force microscope to investigate the effects of cell morphological parameters and confluency on whole-cell mechanical behavior for osteoblastic and fibroblastic cells. For nonconfluent cells, projected nucleus area, cell area, and cell aspect ratio were not correlated with mechanical behavior (p>or=0.46), as characterized by a parallel-spring recruitment model. However, measured force-deformation responses were statistically different between osteoblastic and fibroblastic cells (p<0.001) and between confluent and nonconfluent cells (p<0.001). Osteoblastic cells were 2.3-2.8 times stiffer than fibroblastic cells, and confluent cells were 1.5-1.8 times stiffer than nonconfluent cells. The results indicate that structural differences related to phenotype and confluency affect whole-cell mechanical behavior, while structural differences related to global morphology do not. This suggests that cytoskeleton structural parameters, such as filament density, filament crosslinking, and cell-cell and cell-matrix attachments, dominate inter-cell variability in whole-cell mechanical behavior. PMID:16604293

Jaasma, Michael J; Jackson, Wesley M; Keaveny, Tony M

2006-05-01

49

Passage-dependent morphological and phenotypical changes of a canine histiocytic sarcoma cell line (DH82 cells).  

PubMed

DH82 cells represent a permanent macrophage cell line isolated from a dog with histiocytic sarcoma (HS) and are commonly used in various fields of research upon infection and cancer, respectively. Despite its frequent use, data on cell surface antigen expression of this cell line are fragmentary and in part inconsistent. We therefore aimed at a detailed morphological and antigenic characterization of DH82 cells with respect to passage-dependent differences. Cellular morphology of early (?13) and late (?66) passages of DH82 cells was evaluated via scanning electron microscopy. Moreover, cells were labelled with 10 monoclonal antibodies directed against CD11c, CD14, CD18, CD44, CD45, CD80, CD86, MHC-I, MHC-II, and ICAM-1 for flow cytometric analysis. Early passage cells were characterized by round cell bodies with abundant small cytoplasmic projections whereas later passages exhibited a spindle-shaped morphology with large processes. The percentage of CD11c-, CD14-, CD18-, CD45-, and CD80 positive cells significantly decreased in late passages whereas the expression of CD44, CD86, MHC-I, MHC-II and ICAM-1 remained unchanged. DH82 cells represent a remarkably heterogeneous cell line with divergent antigenic and morphologic properties. The present findings have important implications for future studies, which should consider distinct characteristics with regard to the used passage. PMID:25534080

Heinrich, Franziska; Contioso, Vanessa Bono; Stein, Veronika M; Carlson, Regina; Tipold, Andrea; Ulrich, Reiner; Puff, Christina; Baumgärtner, Wolfgang; Spitzbarth, Ingo

2015-01-15

50

Physical Explanation of Coupled Cell-Cell Rotational Behavior and Interfacial Morphology: A Particle Dynamics Model  

PubMed Central

Previous studies have reported persistent rotational behavior between adherent cell-cell pairs cultured on micropatterned substrates, and this rotation is often accompanied by a sigmoidal deflection of the cell-cell interface. Interestingly, the cell-cell rotation runs in the opposite reference frame from what could be expected of single cell locomotion. Specifically, the rotation of the cell pair consists of each individual cell protruding from the inwardly regressive arm of the cell-cell interface, and retracting from the other outwardly protrusive arm. To this author’s knowledge, the cause of this elusive behavior has not yet been clarified. Here, we propose a physical model based on particle dynamics, accounting for actomyosin forcing, viscous dissipation, and cortical tension. The results show that a correlation in actomyosin force vectors leads to both persistent rotational behavior and interfacial deflection in a simulated cell cluster. Significantly, the model, without any artificial cues, spontaneously and consistently reproduces the same rotational reference frame as experimentally observed. Further analyses show that the interfacial deflection depends predominantly on cortical tension, whereas the cluster rotation depends predominantly on actomyosin forcing. Together, these results corroborate the hypothesis that both rotational and morphological phenomena are, in fact, physically coupled by an intracellular torque of a common origin. PMID:24268142

Leong, Fong Yew

2013-01-01

51

Physical explanation of coupled cell-cell rotational behavior and interfacial morphology: a particle dynamics model.  

PubMed

Previous studies have reported persistent rotational behavior between adherent cell-cell pairs cultured on micropatterned substrates, and this rotation is often accompanied by a sigmoidal deflection of the cell-cell interface. Interestingly, the cell-cell rotation runs in the opposite reference frame from what could be expected of single cell locomotion. Specifically, the rotation of the cell pair consists of each individual cell protruding from the inwardly regressive arm of the cell-cell interface, and retracting from the other outwardly protrusive arm. To this author's knowledge, the cause of this elusive behavior has not yet been clarified. Here, we propose a physical model based on particle dynamics, accounting for actomyosin forcing, viscous dissipation, and cortical tension. The results show that a correlation in actomyosin force vectors leads to both persistent rotational behavior and interfacial deflection in a simulated cell cluster. Significantly, the model, without any artificial cues, spontaneously and consistently reproduces the same rotational reference frame as experimentally observed. Further analyses show that the interfacial deflection depends predominantly on cortical tension, whereas the cluster rotation depends predominantly on actomyosin forcing. Together, these results corroborate the hypothesis that both rotational and morphological phenomena are, in fact, physically coupled by an intracellular torque of a common origin. PMID:24268142

Leong, Fong Yew

2013-11-19

52

Flavonoid-Induced Morphological Modifications of Endothelial Cells Through Microtubule Stabilization  

Microsoft Academic Search

Flavonoids are common components of the human diet and appear to be of interest in cancer prevention or therapy, but their structure-activity relationships (SAR) remain poorly defined. In this study, were compared 24 flavonoids for their cytotoxicity on cancer cells (B16 and Lewis lung) and their morphological effect on endothelial cells (EC) that could predict antiangiogenic activity. Ten flavonoids presented

Yasmine S. Touil; Arlette Fellous; Daniel Scherman; Guy G. Chabot

2009-01-01

53

Shock wave induced cytoskeletal and morphological deformations in a human renal carcinoma cell line.  

PubMed

Effects of shock waves on the morphology and cytoskeleton of a human renal carcinoma cell line (ACHN) were investigated in vitro. ACHN monolayer cultured on a cover slide glass was treated with 10 shots of focused underwater shock waves, with 16 MPa peak pressure at the focal area of a piezoceramic shock wave generator. After exposure to the shock wave, based on the severity of morphological deformations of the treated cells, the monolayer was divided into three morphological areas; focal, marginal and intact. Morphological deformations were found to be associated with disorganization of the intracellular cytoskeletal filaments. Deformation of the cytoskeletal proteins in the treated cells were separately studied with respect to the location of the cells within the three morphological areas. Among three major cytoskeletal proteins, actin and tubulin, but not vimentin, were affected by the shock waves. The deformed cells reorganized their cytoskeletal network within 3 h with a pattern similar to the control, indicating the transient characteristic of the shock wave induced cytoskeletal damage in the surviving cells. The remaining cell fragments on the slide glass, which contained short actin filaments, indicated the important role of shear stress in damaging the cytoskeletal fibers by shock waves. PMID:16630122

Moosavi-Nejad, S Fatemeh; Hosseini, S Hamid R; Satoh, Makoto; Takayama, Kazuyoshi

2006-04-01

54

Endothelial cell modulation of smooth muscle cell morphology and organizational growth pattern.  

PubMed

Intimal hyperplasia is characterized by smooth muscle cell (SMC) dedifferentiation from a contractile to a synthetic phenotype prior to migration and proliferation. Regulatory mechanisms controlling SMC phenotype are not well known. This study examined the effect of endothelial cells (ECs) on SMC morphology in coculture. Subcultured bovine ECs and SMCs were plated on opposite sides of a 13 microns thick, semipermeable membrane (0.45 micron pores, Cyclopore) to allow potential humoral and cellular cross-membrane communication. SMCs were studied (5 wells/group) in coculture opposite confluent ECs (EC/SMC) and alone (SMC controls). After 4 days of culture in Dulbecco's modified Eagle medium/2.5% calf serum, SMCs were harvested. The ratio of protein/DNA was measured as an index of SMC hypertrophy (synthetic SMC phenotype). SMCs were examined with light and scanning electron microscopy to evaluate cell surface area, cellular morphology, and macroscopic growth characteristics. Flow cytometry was used to determine the cellular RNA/DNA ratio. SMC control cultures had a significantly greater protein-to-DNA content than SMCs cocultured with ECs (175 +/- 9 vs. 115 +/- 7 micrograms protein/micrograms DNA; p < 0.001). SMC control cultures also had 6.5 times greater cell surface area (5.8 +/- 0.3 x 10(3) microns2) than cocultured SMCs (0.9 +/- 0.1; p < 0.001). In SMC control cultures, SMC hypertrophy and rapid "hill and valley" formation were observed. In contrast, SMCs from the EC/SMC group exhibited a more spindle-shaped, contractile-appearing phenotype with more uniform, evenly distributed cells and no hill and valley formation. SMC control cultures also had a higher RNA/DNA ratio. Thus the presence of confluent ECs substantially altered the morphology and growth characteristic normally observed for SMCs in vitro. This coculture system provides a model to further study EC-SMC interaction, which could have important in vivo consequences. PMID:8688295

Powell, R J; Cronenwett, J L; Fillinger, M F; Wagner, R J; Sampson, L N

1996-01-01

55

Morphological changes do not reflect biochemical and functional differentiation in OLN-93 oligodendroglial cells.  

PubMed

OLN-93 cells, a cell line established from spontaneously transformed rat brain glial cultures, are used as a model for oligodendrocytes. These cells are known to undergo morphological changes upon serum deprivation. The objective of the present study is to investigate a possible correlation between these morphological changes and (1) the loss or gain of oligodendrocyte markers and (2) the electrophysiological properties of these cells. Using RT-PCR and immunocytochemistry, we demonstrate that the OLN-93 cell line expresses a broad range of markers (NG2, CNP, MAG, MOG) both when cultured in medium containing 10% or 0.5% fetal calf serum. Whole-cell patch-clamp recordings demonstrate that, regardless of the culture conditions, OLN-93 cells mainly express delayed-rectifying K+ currents, a characteristic of immature oligodendrocytes. These currents are in part mediated by the shaker family of voltage-gated potassium channels. Kv1.1 and Kv1.3-expression are present at the mRNA and at the protein levels, and functional evidence for Kv1.3 mediated currents was obtained by using the selective blocker margatoxin. Under low serum conditions, OLN-93 cells exhibit differentiation-like morphological changes. However, we provide evidence that these morphological modifications do not necessarily correlate with biochemical or functional changes. Based on these data, we conclude that the OLN-93 cell line can be situated at a developmental stage between a late pre-oligodendrocyte and a late immature oligodendrocyte, regardless of serum concentration. PMID:19595704

Buckinx, Roeland; Smolders, Inge; Sahebali, Sheen; Janssen, Daniel; Smets, Ilse; Ameloot, Marcel; Rigo, Jean-Michel

2009-10-30

56

Tendon cell outgrowth rates and morphology associated with kevlar-49.  

PubMed

A rat tendon cell model was used to evaluate the in vitro biocompatibility of kevlar-49. The cell response to kevlar was compared to carbon AS-4 and nylon sutures. Three trials were run and cell growth rates were statistically similar for all the materials tested. A separate experiment was conducted in which the same fiber materials were placed in the same Petri dish. Again, the rates were similar for each material. Finally, the cells were observed with a scanning electron microscope, and the three classic cell morphologies associated with this tendon cell model were observed. Also, cellular attachment to the fiber and cellular encapsulation of the fiber were identical for the three materials tested. Kevlar-49 proved to be comparable to carbon AS4 and nylon sutures in terms of cellular response and cell outgrowth rates. PMID:3235468

Zimmerman, M; Gordon, K E

1988-12-01

57

Formulation strategies for optimizing the morphology of polymeric bulk heterojunction organic solar cells: a brief review  

NASA Astrophysics Data System (ADS)

Polymeric bulk heterojunction (BHJ) organic solar cells represent one of the most promising technologies for renewable energy with a low fabrication cost. Control over BHJ morphology is one of the key factors in obtaining high-efficiency devices. This review focuses on formulation strategies for optimizing the BHJ morphology. We address how solvent choice and the introduction of processing additives affect the morphology. We also review a number of recent studies concerning prediction methods that utilize the Hansen solubility parameters to develop efficient solvent systems.

Vongsaysy, Uyxing; Bassani, Dario M.; Servant, Laurent; Pavageau, Bertrand; Wantz, Guillaume; Aziz, Hany

2014-01-01

58

Measurement of red blood cell mechanics during morphological changes  

NASA Astrophysics Data System (ADS)

The human red blood cell (RBC) membrane, a fluid lipid bilayer tethered to an elastic 2D spectrin network, provides the principal control of the cell's morphology and mechanics. These properties, in turn, influence the ability of RBCs to transport oxygen in circulation. Current mechanical measurements of RBCs rely on external loads. Here we apply a Noncontact optical interferometric technique to quantify the thermal fluctuations of RBC membranes with 3 nm accuracy over a broad range of spatial and temporal frequencies. Combining this technique with a new mathematical model describing RBC membrane undulations, we measure the mechanical changes of RBCs as they undergo a transition from the normal discoid shape to the abnormal echinocyte and spherical shapes. These measurements indicate that, coincident with this morphological transition, there is a significant increase in the membrane's shear and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

Popescu, Gabriel; Park, Yongkeun; Best, Catherine; Dasari, Ramachandra; Feld, Michael; Kuriabova, Tatiana; Henle, Mark; Levine, Alex

2010-03-01

59

Similar morphological and molecular signatures shared by female and male germline stem cells  

PubMed Central

The existence of mammalian female germline stem cells (FGSCs) indicates that mammalian ovaries possess germline stem cells analogous to testis, and continue to produce gametes postnatally, which provides new insights into female fertility. In this study, we compared the morphological and molecular characteristics between FGSCs and spermatogonial stem cells (SSCs) by analysis of morphology, immunofluorescence, alkaline phosphatase activity assay, reverse transcription polymerase chain reaction (RT-PCR) and microarray hybridization. The results demonstrated that the morphology and growth patterns of FGSCs are similar to those of SSCs. Microarray analysis of global gene expression profiles of FGSCs and SSCs showed similar signatures in the transcriptome level. A list of 853 co-highly expressed genes (CEG) in female and male germline stem cells may be responsible for the morphological and molecular similarity. We constructed a continuous network of the CEG based on I2D protein-protein interaction database by breadth first search. From the network, we could observe the interactions of the CEG may be responsible for maintaining the properties of germline stem cells. This study was the first attempt to compare morphological and molecular characteristics between FGSCs and SSCs. These findings would provide some clues for further research on mammalian FGSCs. PMID:24993338

Xie, Wenhai; Wang, Hu; Wu, Ji

2014-01-01

60

A study on the improved growth rate and morphology of chemically deposited ZnS thin film buffer layer for thin film solar cells in acidic medium  

Microsoft Academic Search

Zinc sulfide (ZnS) thin films have been prepared by chemical bath deposition method with improving growth rate and morphology using the mixed complexing agents of ethylenediamine tetra-acetate disodium salt (Na2EDTA) and hexamethylenetetramine (HMTA). The effects of HMTA quantity on the morphological, compositional, optical, structural and electrical properties of ZnS thin films with fixed Na2EDTA concentration have been investigated. ZnS thin

Seung Wook Shin; So Ra Kang; K. V. Gurav; Jae Ho Yun; Jong-Ha Moon; Jeong Yong Lee; Jin Hyeok Kim

2011-01-01

61

Taxonomic study and morphological differentiation of an actinomycete genus, Kitasatospora.  

PubMed

The history and taxonomic criteria of the actinomycete genus, Kitasatospora, are described. The reasons for a change of the position of the genus in the classification system are given and a restriction length polymorphism (RFLP) method for rapid identification is described. Although the bacterial genus, Kitasatospora, resembles the fungal one, Streptomyces, in its morphology, it is clearly different in its cell-wall composition which includes LL- and meso-DAP, glycine and galactose. Following a change in its taxonomic position as a result of insufficient gene analysis, it was re-established by phylogenetic analysis of the entire 16S rRNA gene. Most actinomycetes produce bioactive compounds but the relationship between antibiotic production and morphology has not been studied in detail. Kitasatospora strains may be used as a model because they grow in submerged culture like those actinomycetes strains which produce bioactive compounds. The authors suggest further studies of the correlation between metabolic and morphological differentiation and the mechanism of the production of submerged spores. PMID:10467659

Takahashi, Y; Seino, A; Iwai, Y; Omura, S

1999-07-01

62

Morphology and morphometrics of hematological cells from eastern sarus crane, Grus antigone sharpii  

Microsoft Academic Search

The population of the eastern sarus crane (Grus antigone sharpii) has been greatly reduced both in distribution and number, and documents presenting the blood cell characteristics and morphometric\\u000a data of blood cells in this kind of bird are limited. The objective of this study was to examine the morphometric and morphological\\u000a aspects of the blood cells of the eastern sarus

N.-A. Narkkong; Worapol Aengwanich; A. Tanomthong

2011-01-01

63

Expression of VHL Causes Three-Dimensional Morphological Changes in Renal Cells Indicative of Proximal Tubule Differentiation  

PubMed Central

Mutations in the von Hippel-Lindau (VHL) tumor suppressor gene are responsible for the VHL hereditary cancer syndrome, and are associated with the majority of clear cell renal cell carcinomas. In this study, scanning electron microscopy of VHL-negative renal carcinoma cells was utilized to examine the effects of VHL re-expression on the morphology of these cells. Significant differences were observed between the morphology of VHL-negative control cells and those with reintroduced VHL, with VHL expression mediating an apical surface that mounded upward, as opposed to the flat surfaces seen with VHL-negative cells. In long term cultures, rounded VHL-expressing cells grew in clusters on top the monolayer, and microvilli were observed on the apical face of these cells, in a manner suggestive of proximal tubule differentiation. In contrast, VHL-negative cells remained flat and did not develop microvilli in long-term cultures. Since VHL is a key member of an ubiquitin E3 ligase complex whose best known target is hypoxia-inducible factor alpha (HIF-?), we looked at the effects of HIF-? expression on cell morphology. Knockdown of HIF-2? in cells that only express this isoform had no effect on the morphology of the cells. These results indicate that VHL expression directs three dimensional morphological changes in renal cells indicative of differentiation, and while dysregulation of HIF-? may be necessary for tumorigenesis following VHL loss, it is not the major determinant of these VHL-mediated morphological changes. PMID:24308012

Chiatar, Shivannah S; Eze, Ogechukwu P; Schoenfeld, Alan R

2013-01-01

64

Morphology control of zinc regeneration for zinc-air fuel cell and battery  

NASA Astrophysics Data System (ADS)

Morphology control is crucial both for zinc-air batteries and for zinc-air fuel cells during zinc regeneration. Zinc dendrite should be avoided in zinc-air batteries and zinc pellets are yearned to be formed for zinc-air fuel cells. This paper is mainly to analyze the mechanism of shape change and to control the zinc morphology during charge. A numerical three-dimensional model for zinc regeneration is established with COMSOL software on the basis of ionic transport theory and electrode reaction electrochemistry, and some experiments of zinc regeneration are carried out. The deposition process is qualitatively analyzed by the kinetics Monte Carlo method to study the morphological change from the electrocrystallization point of view. Morphological evolution of deposited zinc under different conditions of direct currents and pulse currents is also investigated by simulation. The simulation shows that parametric variables of the flowing electrolyte, the surface roughness and the structure of the electrode, the charging current and mode affect morphological evolution. The uniform morphology of deposited zinc is attained at low current, pulsating current or hydrodynamic electrolyte, and granular morphology is obtained by means of an electrode of discrete columnar structure in combination with high current and flowing electrolyte.

Wang, Keliang; Pei, Pucheng; Ma, Ze; Xu, Huachi; Li, Pengcheng; Wang, Xizhong

2014-12-01

65

Label-free observation of three-dimensional morphology change of a single PC12 cell by digital holographic microscopy.  

PubMed

Observation of three-dimensional (3D) morphology changes of a single mammalian cell is very useful to understand cell response for various stimuli. Conventional techniques to evaluate morphology changes with sufficient precision and high temporal resolution are limited. For example, the confocal fluorescence microscope is available to take 3D morphology changes, whereas fluorescence microscopic observation requires labeling the cells with fluorescence dye. Recently, a novel imaging method based on digital holography was developed for nonlabeling microscopic observation of 3D morphology. Digital holographic microscopy has high potentiality in digital focusing properties, video-frequency capability, noninvasive operation, and so forth. It obtains a quantitative phase image of a living cell from a single recorded hologram, with interferometric accuracy, and surveys the rapid morphology change of a single cell. In this study, digital holographic microscopy was applied to monitor the 3D morphology change of an individual PC12 cell, a nerve model cell, subjected to high K(+) stimulation. Phase images of the rapidly swelling cell were acquired, and time lapse reconstruction of 3D cell morphology was performed from phase images. Our results demonstrate that digital holographic imaging is a powerful new tool for evaluation of cell response against various stimulants without any labeling reagent. PMID:22796499

Mir, Tanveer Ahamd; Shinohara, Hiroaki

2012-10-01

66

Morphological characterisation of BGM (Buffalo Green Monkey) cell line exposed to low doses of cadmium chloride.  

PubMed

Morphological changes in the Buffalo Green Monkey (BGM) cell line after exposure to a subcytotoxic dose (0.062 mM, equivalent to EC(10)-effective concentration 10%) of cadmium chloride have been evaluated. Cells were exposed for 24 h and the effects observed at the ultrastructural level by transmission and scanning microscopy. Using transmission electron microscopy, the most notable findings in treated cells were the presence of intranuclear inclusion bodies and thin intracytoplasmic granules associated to myelin figures and the presence of apoptotic bodies. Other morphological alterations included cell vacuolisation and a reduced cytoplasm volume, condensation of the mitochondria and a decreased number of cytoplasmic organelles, except lysosomes and autophagic vacuoles, which increased in number. Scanning electron microscopy pointed to a cell with a disrupted perinuclear region and a decrease in the number of surface microvilli. We conclude that the BGM cell line may be considered an useful tool for toxicological studies involving cadmium. PMID:12781208

Romero, D; Gómez-Zapata, M; Luna, A; García-Fernández, A J

2003-06-01

67

ACME: Automated Cell Morphology Extractor for Comprehensive Reconstruction of Cell Membranes  

PubMed Central

The quantification of cell shape, cell migration, and cell rearrangements is important for addressing classical questions in developmental biology such as patterning and tissue morphogenesis. Time-lapse microscopic imaging of transgenic embryos expressing fluorescent reporters is the method of choice for tracking morphogenetic changes and establishing cell lineages and fate maps in vivo. However, the manual steps involved in curating thousands of putative cell segmentations have been a major bottleneck in the application of these technologies especially for cell membranes. Segmentation of cell membranes while more difficult than nuclear segmentation is necessary for quantifying the relations between changes in cell morphology and morphogenesis. We present a novel and fully automated method to first reconstruct membrane signals and then segment out cells from 3D membrane images even in dense tissues. The approach has three stages: 1) detection of local membrane planes, 2) voting to fill structural gaps, and 3) region segmentation. We demonstrate the superior performance of the algorithms quantitatively on time-lapse confocal and two-photon images of zebrafish neuroectoderm and paraxial mesoderm by comparing its results with those derived from human inspection. We also compared with synthetic microscopic images generated by simulating the process of imaging with fluorescent reporters under varying conditions of noise. Both the over-segmentation and under-segmentation percentages of our method are around 5%. The volume overlap of individual cells, compared to expert manual segmentation, is consistently over 84%. By using our software (ACME) to study somite formation, we were able to segment touching cells with high accuracy and reliably quantify changes in morphogenetic parameters such as cell shape and size, and the arrangement of epithelial and mesenchymal cells. Our software has been developed and tested on Windows, Mac, and Linux platforms and is available publicly under an open source BSD license (https://github.com/krm15/ACME). PMID:23236265

Mosaliganti, Kishore R.; Noche, Ramil R.; Xiong, Fengzhu; Swinburne, Ian A.; Megason, Sean G.

2012-01-01

68

Investigation of cell morphology by the TRUImagE digital holographic microscopy system  

NASA Astrophysics Data System (ADS)

We report the development of the Three-dimensional Real-time Uninvasive Imaging and Evaluation (TRUImagE) system based on digital holographic microscopy to study the morphological changes in cells undergoing photodynamic therapyinduced cell death. The optical system, based on the Michelson interferometer and configured in transmission mode, and the sample holder incorporating a stage incubator have been developed for monitoring various tumorigenic cell samples without the use of markers. Off-axis digital holograms were recorded with a CCD sensor and numerically reconstructed to provide quantitative phase imaging and 3D morphology of the cells in real time. The system was used to continuously monitor and study, at different time points, the changes in cells after incubation with the photosensitizer followed by activation by the appropriate light dose. Results obtained from the TRUImagE system and biochemical assays will be given.

Chee, Oi Choo; Qu, Weijuan; Chai, Kim Kheong; Asundi, Anand

2012-06-01

69

Morphological Features of Cell Blocks Prepared from Residual Liqui-PREP Samples Can Distinguish between High-Grade Squamous Intraepithelial Lesions and Squamous Cell Carcinomas  

Microsoft Academic Search

Objective: To evaluate the diagnostic value and compare morphological features of cell block sections of high-grade squamous intraepithelial lesions (HSIL) and squamous cell carcinomas (SCC). Study Design: A total of 135 cell blocks were prepared from residual Liqui-PREP samples. Of these, 43 biopsy-confirmed cases (24 HSIL and 19 SCC) were reviewed. Morphological features determined included cell clusters, epithelial-stromal interface, stromal

Qingzhu Wei; Jianghuan Liu; Zhixiong Zhang; Qiao Yang; Tong Zhao

2011-01-01

70

Morphology matters in immune cell chemotaxis: membrane asymmetry affects amplification  

NASA Astrophysics Data System (ADS)

A key mediator of eukaryotic chemotaxis is the asymmetric accumulation of phosphatidylinositol-3,4,5-triphosphate (PIP3) on the cell membrane. Recent work has focused on understanding how a shallow external gradient of chemoattractant leads to an amplified internal gradient of PIP3. In this paper we dissect what fraction of this amplification is derived biochemically by the signal transduction network and how much arises entirely from the effects of cell morphology. Here we identify and formalize the role of morphology in signal detection and demonstrate its effects through simulation and experiments. Our key result is that an asymmetric distribution of membrane accounts for approximately one-half of the measured amplification from ligand concentration to PIP3 production. We also show that the underlying biochemical network behaves as a linear amplifier in the micropipette assay.

Onsum, Matthew David; Wong, Kit; Herzmark, Paul; Bourne, Henry R.; Arkin, Adam Paul

2006-09-01

71

Bone cell elasticity and morphology changes during the cell cycle  

Microsoft Academic Search

The mechanical properties of cells are reported to be regulated by a range of factors including interactions with the extracellular environment and other cells, differentiation status, the onset of pathological states, as well as the intracellular factors, for example, the cytoskeleton. The cell cycle is considered to be a well-ordered sequence of biochemical events. A number of processes reported to

Geraldine M. Kelly; Jason I. Kilpatrick; Maarten H. van Es; Paul P. Weafer; Patrick J. Prendergast; Suzanne P. Jarvis

2011-01-01

72

A Study of Unbalanced Morphological Understanding: Morphological Land Use Patterns Analysis of U.S. Megaregions  

E-print Network

Problem: This study identifies some issues in the definitions of US megaregions which have strongly emphasized functional relationships without considering morphological characteristics. An extensive review of the literature revealed...

Ko, Youngho

2012-07-16

73

Semantic processing during morphological priming: an ERP study.  

PubMed

Previous research has yielded conflicting results regarding the onset of semantic processing during morphological priming. The present study was designed to further explore the time-course of morphological processing using event-related potentials (ERPs). We conducted a primed lexical decision study comparing a morphological (LAVAGE - laver [washing - wash]), a semantic (LINGE - laver [laundry - wash]), an orthographic (LAVANDE - laver [lavender - wash]), and an unrelated control condition (HOSPICE - laver [nursing home - wash]), using the same targets across the four priming conditions. The behavioral data showed significant effects of morphological and semantic priming, with the magnitude of morphological priming being significantly larger than the magnitude of semantic priming. The ERP data revealed significant morphological but no semantic priming at 100-250 ms. Furthermore, a reduction of the N400 amplitude in the morphological condition compared to the semantic and orthographic condition demonstrates that the morphological priming effect was not entirely due to the semantic or orthographic overlap between the prime and the target. The present data reflect an early process of semantically blind morphological decomposition, and a later process of morpho-semantic decomposition, which we discuss in the context of recent morphological processing theories. PMID:25020124

Beyersmann, Elisabeth; Iakimova, Galina; Ziegler, Johannes C; Colé, Pascale

2014-09-01

74

Influence of Sutherlandia frutescens extracts on cell numbers, morphology and gene expression in MCF-7 cells.  

PubMed

Sutherlandia frutescens is a well-known South African herbal remedy traditionally used for stomach problems, internal cancers, diabetes, various inflammatory conditions and recently to improve the overall health in cancer and HIV/AIDS patients. The influence of crude Sutherlandia frutescens extracts (prepared with 70% ethanol) was investigated on cell numbers, morphology, and gene expression profiles in a MCF-7 human breast adenocarcinoma cell line. Time-dependent (24, 34, 48 and 72 h) and dose-dependent (0.5-2.5 mg/ml) studies were conducted utilizing spectrophotometrical analysis with crystal violet as DNA stain. A statistically significant decrease to 50% of malignant cell numbers was observed after 24 h of exposure to 1.5 mg/ml Sutherlandia frutescens extract when compared to vehicle-treated controls. Morphological characteristics of apoptosis including cytoplasmic shrinking, membrane blebbing and apoptotic bodies were observed after 24h of exposure. A preliminary global gene expression profile was obtained by means of microarray analysis and revealed valuable information about the molecular mechanisms and signal transduction associated with 70% ethanolic Sutherlandia frutescens extracts. PMID:17433588

Stander, B A; Marais, S; Steynberg, T J; Theron, D; Joubert, F; Albrecht, C; Joubert, A M

2007-06-13

75

Morphological Awareness and Chinese Children's Literacy Development: An Intervention Study  

ERIC Educational Resources Information Center

The purpose of this study was to investigate the relationship between morphological awareness and Chinese children's literacy development. Of the 169 children from elementary schools in Beijing, China, who participated in the study, about half received enhanced instruction on the morphology of characters and words in the first and second grade. At…

Wu, Xiaoying; Anderson, Richard C.; Li, Wenling; Wu, Xinchun; Li, Hong; Zhang, Jie; Zheng, Qiu; Zhu, Jin; Shu, Hua; Jiang, Wei; Chen, Xi; Wang, Qiuying; Yin, Li; He, Yeqin; Packard, Jerome; Gaffney, Janet S.

2009-01-01

76

Variable cell morphology approach for individual-based modeling of microbial communities.  

PubMed

An individual-based, mass-spring modeling framework has been developed to investigate the effect of cell properties on the structure of biofilms and microbial aggregates through Lagrangian modeling. Key features that distinguish this model are variable cell morphology described by a collection of particles connected by springs and a mechanical representation of deformable intracellular, intercellular, and cell-substratum links. A first case study describes the colony formation of a rod-shaped species on a planar substratum. This case shows the importance of mechanical interactions in a community of growing and dividing rod-shaped cells (i.e., bacilli). Cell-substratum links promote formation of mounds as opposed to single-layer biofilms, whereas filial links affect the roundness of the biofilm. A second case study describes the formation of flocs and development of external filaments in a mixed-culture activated sludge community. It is shown by modeling that distinct cell-cell links, microbial morphology, and growth kinetics can lead to excessive filamentous proliferation and interfloc bridging, possible causes for detrimental sludge bulking. This methodology has been extended to more advanced microbial morphologies such as filament branching and proves to be a very powerful tool in determining how fundamental controlling mechanisms determine diverse microbial colony architectures. PMID:24806936

Storck, Tomas; Picioreanu, Cristian; Virdis, Bernardino; Batstone, Damien J

2014-05-01

77

Morphology, drug release, antibacterial, cell proliferation, and histology studies of chamomile-loaded wound dressing mats based on electrospun nanofibrous poly(?-caprolactone)/polystyrene blends.  

PubMed

For the first time, it has been tried to achieve optimum conditions for electrospun poly(?-caprolactone)/polystyrene (PCL/PS) nanofibrous samples as active wound dressings containing chamomile via D-optimal design approach. In this work, systematic in vitro and in vivo studies were carried out by drug release rate, antibacterial and antifungal evaluations, cell culture, and rat wound model along with histology observation. The optimized samples were prepared under the following electrospinning conditions: PCL/PS ratio (65/35), PCL concentration 9%(w/v), PS concentration 14%(w/v), distance between the syringe needle tip and the collector 15.5 cm, applied voltage 18 kV, and solution flow rate 0.46 mL h(-1) . The FE-SEM micrographs showed electrospun PCL/PS (65/35) nanofibrous sample containing 15% chamomile had a minimum average diameter (?175 nm) compared to the neat samples (?268 nm). The drug released resulted in a gradual and high amount of chamomile from the optimized PCL/PS nanofibrous sample (?70%) in respect to PCL and PS nanofibers after 48 h. This claim was also confirmed by antibacterial and antifungal evaluations in which an inhibitory zone with a diameter of about 7.6 mm was formed. The rat wound model results also indicated that the samples loaded with 15% chamomile extract were remarkably capable to heal the wounds up to 99?±?0.5% after 14 days post-treatment periods. The adhesion of mesenchymal stem cells and their viability on the optimized samples were confirmed by MTT analysis. Also, the electrospun nanofibrous mats based on PCL/PS (65/35) showed a high efficiency in the wound closure and healing process compared to the reference sample, PCL/PS nanofibers without chamomile. Finally, the histology analysis revealed that the formation of epithelial tissues, the lack of necrosis and collagen fibers accumulation in the dermis tissues for the above optimized samples. PMID:24259351

Motealleh, Behrooz; Zahedi, Payam; Rezaeian, Iraj; Moghimi, Morvarid; Abdolghaffari, Amir Hossein; Zarandi, Mohammad Amin

2014-07-01

78

Morphological cladistic study of coregonine fishes  

USGS Publications Warehouse

A cladistic analysis of 50 characters from 26 taxa of coregonine fishes and two outgroup taxa yields a phylogenetic tree with two major branches, best summarized as two genera - Prosopium and Coregonus. Presence of teeth on the palatine, long maxillae, and long supra-maxillae are primitive, whereas loss of teeth, short or notched maxillae, and short supermaxillae are derived traits. P. coulteri and C. huntsmani are morphologically and phylogenetically primitive members of their groups. The widespread species, P. cylindraceum and P. williamsoni are morphologically advanced in parallel with the subgenus Coregonus (whitefishes): they share subterminal mouths, short jaws, and reduced teeth. Prosopium gemmifer parallels the ciscoes, subgenus Leucichthys. The whitefishes, C. ussuriensis, C. lavaretus, C. clupeaformis, and C. nasus are a monophyletic group, the subgenus Coregonus. The subgenus Leucichthys is a diverse, relatively plesiomorphic assemblage, widespread in the Holarctic region. This assemblage includes the inconnu, Stenodus.

Smith, G.R.; Todd, T.N.

1992-01-01

79

Morphological features of the human umbilical vein in normal, sickle cell trait, and sickle cell disease pregnancies.  

PubMed

Pathological changes often occur in the placenta of women with sickle cell disease (SCD). These alterations are caused by sickling of erythrocytes and vasoocclusion in the placental circulation, leading to regional hypoxia. However, the morphological status of the umbilical cord, which is in close physical association with the placenta, is not documented under such conditions. To explore this, the umbilical vein structure in healthy, sickle cell trait (the heterozygous state), and SCD pregnancies was studied using scanning (SEM) and transmission electron microscopy (TEM). Interestingly, the sickle cell trait umbilical vein architecture was morphologically similar to that in control veins, whereas numerous alterations were seen in the SCD umbilical vein wall. In SEM, the SCD umbilical vein endothelial cells showed atypical morphologies. TEM analysis of the tunica media showed (1) smooth muscle cell proliferation and increase in the thickness of the basement membrane underlying the cells; (2) areas of necrosis; (3) reduplication of the inner elastic lamina. Such features were often seen in sickle patients vasculature at autopsy. Our findings could have importance because tissue hypoxemia is an integral part of vasoocclusion. We conclude that the SCD umbilical vein may be an additional tool for studying vasoocclusion in sickle cell disease. PMID:9923921

Decastel, M; Leborgne-Samuel, Y; Alexandre, L; Merault, G; Berchel, C

1999-01-01

80

Determining Drug Efficacy Using Plasmonically Enhanced Imaging of the Morphological Changes of Cells upon Death.  

PubMed

Recently, we utilized the optical properties of gold nanoparticles (AuNPs) for plasmonically enhanced Rayleigh scattering imaging spectroscopy (PERSIS), a new technique that enabled the direct observation of AuNP localization. In this study, we employ PERSIS by using AuNPs as light-scattering probes to compare the relative efficacy of three chemotherapeutic drugs on human oral squamous carcinoma cells. Although the drugs induced apoptotic cell death through differing mechanisms, morphological changes including cell membrane blebbing and shrinkage, accompanied by an increase in white light scattering, were visually evident. By utilizing the AuNPs to increase the cells' inherent Rayleigh scattering, we have obtained the time profile of cell death from the anticancer drugs using a single sample of cells in real time, using inexpensive equipment available in any lab. From this time profile, we calculated cell death enhancement factors to compare the relative efficacies of the different drugs using our technique, which corresponded to those calculated from the commonly used XTT cell viability assay. Although this technique does not impart molecular insights into cell death, the ability to quantitatively correlate cell death to morphological changes suggests the potential use of this technique for the rapid screening of drug analogues to determine the most effective structure against a disease or cell line. PMID:25346800

Aioub, Mena; Austin, Lauren A; El-Sayed, Mostafa A

2014-10-16

81

Morphology of the Epidermis of the Neotropical Catfish Pimelodella lateristriga (Lichtenstein, 1823) with Emphasis in Club Cells  

PubMed Central

The epidermis of Ostariophysi fish is composed of 4 main cell types: epidermal cells (or filament containing cells), mucous cells, granular cells and club cells. The morphological analysis of the epidermis of the catfish Pimelodella lateristriga revealed the presence of only two types of cells: epidermal and club cells. The latter were evident in the middle layer of the epidermis, being the largest cells within the epithelium. Few organelles were located in the perinuclear region, while the rest of the cytoplasm was filled with a non-vesicular fibrillar substance. Club cells contained two irregular nuclei with evident nucleoli and high compacted peripheral chromatin. Histochemical analysis detected prevalence of protein within the cytoplasm other than carbohydrates, which were absent. These characteristics are similar to those described to most Ostariophysi studied so far. On the other hand, the epidermal cells differ from what is found in the literature. The present study described three distinct types, as follows: superficial, abundant and dense cells. Differences among them were restricted to their cytoplasm and nucleus morphology. Mucous cells were found in all Ostariophysi studied so far, although they were absent in P. lateristriga, along with granular cells, also typical of other catfish epidermis. The preset study corroborates the observations on club cells' morphology in Siluriformes specimens, and shows important differences in epidermis composition and cell structure of P. lateristriga regarding the literature data. PMID:23226253

Damasceno, Eduardo Medeiros; Monteiro, Juliana Castro; Duboc, Luiz Fernando; Dolder, Heidi; Mancini, Karina

2012-01-01

82

Influence of curvature on the morphology of brain microvascular endothelial cells  

NASA Astrophysics Data System (ADS)

There are hundreds or thousands of endothelial cells around the perimeter of a single artery or vein, and hence an individual cell experiences little curvature. In contrast, a single endothelial cell may wrap around itself to form the lumen of a brain capillary. Curvature plays a key role in many biological, chemical and physical processes, however, its role in dictating the morphology and polarization of brain capillary endothelial cells has not been investigated. We hypothesize that curvature and shear flow play a key role in determining the structure and function of the blood-brain barrier (BBB). We have developed the ``rod'' assay to study the influence of curvature on the morphology of confluent monolayers of endothelial cells. In this assay cells are plated onto glass rods pulled down to the desired diameter in the range from 5 -- 500 ?m and coated with collagen. We show that curvature has a significant influence on the morphology of endothelial cells and may have an important role in blood-brain barrier function.

Ye, Mao; Yang, Zhen; Wong, Andrew; Searson, Peter

2013-03-01

83

Morphological and functional changes of dissociated single pancreatic acinar cells: testing the suitability of the single cell as a model for exocytosis and calcium signaling  

Microsoft Academic Search

Isolated single pancreatic acinar cells have long been used as a model for studying many kinds of signaling processes due to their structural and functional polarities, but without significant validation. In this study, we examined the morphological and functional changes of dissociated single pancreatic acinar cells.Acutely isolated single cells showed a collapsed membrane potential and a much reduced secretion of

Myoung Kyu Park; Misun Lee; Ole H Petersen

2004-01-01

84

Cryptococcal Cell Morphology Affects Host Cell Interactions and Pathogenicity  

E-print Network

of America Abstract Cryptococcus neoformans is a common life-threatening human fungal pathogen. The size, increasing resistance to oxidative and nitrosative stress, and correlated with reduced penetration of host tissues, while yeast cells can easily disseminate through the blood and lymph systems to spread

Blanchette, Robert A.

85

Cell reconstruction of the rectal mucosa in patients with familial adenomatous polyposis: endoscopy, morphology, immunohistochemistry.  

PubMed

We propose a new surgical approach to the treatment of familial colorectal adenomatous polyposis implying preservation of a portion of the rectum with removed mucosa. For reconstruction of the rectum, allotransplantation of the mixed culture of fetal allogenic somatic cells of the intestinal epithelium and mesenchymal cells of various origin is used. The mechanisms of mucosa reparation were studied in 34 patients. Endoscopic, morphological, and immunohistochemical studies showed that cell transplantation considerably accelerated reparation of the mucosa in mucosectomized rectum. The proposed treatment of familial colorectal adenomatous polyposis allows delaying the development of rectal polyps and cancer for many years. PMID:25257440

Kogan, E A; Vyshegorodtsev, D V; Faizullina, N M; Demura, T A; Kuz'minov, A M; Shelygin, Yu A; Sukhikh, G T

2014-09-01

86

Organic solar cells: An overview focusing on active layer morphology Travis L. Benanti & D. Venkataraman*  

E-print Network

Review Organic solar cells: An overview focusing on active layer morphology Travis L. Benanti & D/acceptor blend, morphology, photovoltaic devices, plastic solar cells, thin films Abstract Solar cells heterojunction concept. This review provides an overview of organic solar cells. Topics covered include: a brief

Venkataraman, Dhandapani "DV"

87

The effect of mineral coating morphology on mesenchymal stem cell attachment and expansion  

PubMed Central

Previous studies have demonstrated the influence of calcium phosphate (CaP) mineral coating characteristics on cell attachment, proliferation, and differentiation. However, the wide range of mineral properties that can potentially influence cell behavior calls for an efficient platform to screen for the effects of specific mineral properties. To address this need, we have developed an efficient well-plate format to probe for the effects of mineral coating properties on stem cell behavior. Specifically, here we systematically controlled mineral coating morphology by modulating ion concentrations in modified simulated body fluids (mSBF) during mineral nucleation and growth. We found that mineral micro-morphology could be gradually changed from spherulitic, to plate-like, to net-like depending on [Ca2+] and [PO43?] in mSBF solutions, while other mineral properties (Ca/P ratio, crystallinity, dissolution rate) remained constant. Differences in mineral morphology resulted in significant differences in stem cell attachment and expansion in vitro. These findings suggest that an enhanced throughput mineral coating format may be useful to identify mineral coating properties for optimal stem cell attachment and expansion, which may ultimately permit efficient intraoperative seeding of patient derived stem cells.

Choi, Siyoung

2015-01-01

88

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

PubMed Central

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

Lascola, Christopher D.; Kraig, Richard P.

2009-01-01

89

Computational study of actin morphology and rheology  

E-print Network

The cytoskeletal network consisting mainly of actin and actin binding proteins is highly dynamic, provides structural integrity to cells, and plays a central role in a wide range of mechanical and biological functions such ...

Kim, Taeyoon, Ph.D. Massachusetts Institute of Technology

2011-01-01

90

Bone marrow stromal cell adhesion and morphology on micro- and sub-micropatterned titanium.  

PubMed

The objective of this study was to investigate the adhesion and morphology of bone marrow derived stromal cells (BMSCs) on bulk titanium (Ti) substrates with precisely-patterned surfaces consisting of groove-based gratings with groove widths ranging from 50 micro m down to 0.5 micro m (500 nm). Although it is well known that certain surface patterning enhances osteoblast (bone-forming cell) functions, past studies on cell-pattern interactions reported in the literature have heavily relied on surface patterning on materials with limited clinical relevance for orthopedic applications, such as polymeric substrates. The clinical need for improving osseointegration and juxtaposed bone formation around load-bearing Ti implants motivated this in vitro study. BMSCs were selected as model cells due to their important role in bone regeneration. The results showed significantly greater BMSC adhesion density and more favorable cell morphology on sub-micropatterned gratings when compared with larger micropatterned gratings and non-patterned control surfaces after both 24 hr and 72 hr cultures. We observed increasing cellular alignment and elongation with decreasing feature size. We also identified two distinctive cellular morphologies: Type I-Attached and spread cells that elongated along the pattern axes; and Type II-Superficially adhered round cells. Sub-micropatterned gratings demonstrated significantly greater Type I cell density than the non-patterned control, and lower Type II cell density than the larger micropatterned gratings. Collectively, these results suggest potential for rationally designing nano-scale surface topography on Ti implants to improve osseointegration. PMID:24734518

Cipriano, Aaron F; De Howitt, Natalie; Gott, Shannon C; Miller, Christopher; Rao, Masaru P; Liu, Huinan

2014-04-01

91

Atypical blast morphology of primary plasma cell leukemia with renal involvement and plasmablasts in urine.  

PubMed

Primary plasma cell leukemia (PCL) is a rare and aggressive variant of plasma cell (PC) myeloma characterized by high levels of circulating PCs. Clinical presentation is like other acute leukemia, with extramedullary infiltration of various tissues and organs being a frequent complication. The disease has a fulminant course and poor prognosis. Morphology of PCs in PCL includes a spectrum of maturity, with most cases having lymphoplasmacytoid or plasmablastic morphology. Presentation as more primitive cells that do not resemble PCs is even rarer and requires additional morphological and immunophenotypic studies. We present a case of 79-year-old woman who presented with severe pancytopenia and lobar pneumonia. Laboratory and clinical evaluation revealed primary, nonsecretory PCL with atypical, immature blast morphology, extramedullary renal involvement, and plasmablasts in urine. Despite therapeutic efforts the patient succumbed to the disease. Detection of PCs in the urine indicates extramedullary spread of disease, especially without accompanying hematuria, and may contribute to impairment of renal function, what is already a frequent complication in these patients. Diagn. Cytopathol. 2015;43:158-162. © 2014 Wiley Periodicals, Inc. PMID:24828023

Pavlovic, Antonia; Ostojic Kolonic, Slobodanka; Radic Kristo, Delfa; Jelic Puskaric, Biljana; Kardum Skelin, Ika

2015-02-01

92

Morphology and photoluminescence study of titania nanoparticles.  

PubMed

Titania nanoparticles are prepared by sol-gel chemistry with a poly(ethylene oxide) methyl ether methacrylate-block-poly(dimethylsiloxane)-block-poly(ethylene oxide) methyl ether methacrylate triblock copolymer acting as the templating agent. The sol-gel components-hydrochloric acid, titanium tetraisopropoxide, and triblock copolymer-are varied to investigate their effect on the resulting titania morphology. An increased titania precursor or polymer content yields smaller primary titania structures. Microbeam grazing incidence small-angle X-ray scattering measurements, which are analyzed with a unified fit model, reveal information about the titania structure sizes. These small structures could not be observed via the used microscopy techniques. The interplay among the sol-gel components via our triblock copolymer results in different sized titania nanoparticles with higher packing densities. Smaller sized titania particles, (?13-20 nm in diameter) in the range of exciton diffusion length, are formed by 2% by weight polymer and show good crystallinity with less surface defects and high oxygen vacancies. PMID:21765580

Memesa, Mine; Lenz, Sebastian; Emmerling, Sebastian G J; Nett, Sebastian; Perlich, Jan; Müller-Buschbaum, Peter; Gutmann, Jochen S

2011-06-01

93

Maintenance of the Cell Morphology by MinC in Helicobacter pylori  

PubMed Central

In the model organism Escherichia coli, Min proteins are involved in regulating the division of septa formation. The computational genome analysis of Helicobacter pylori, a gram-negative microaerophilic bacterium causing gastritis and peptic ulceration, also identified MinC, MinD, and MinE. However, MinC (HP1053) shares a low identity with those of other bacteria and its function in H. pylori remains unclear. In this study, we used morphological and genetic approaches to examine the molecular role of MinC. The results were shown that an H. pylori mutant lacking MinC forms filamentous cells, while the wild-type strain retains the shape of short rods. In addition, a minC mutant regains the short rods when complemented with an intact minCHp gene. The overexpression of MinCHp in E. coli did not affect the growth and cell morphology. Immunofluorescence microscopy revealed that MinCHp forms helix-form structures in H. pylori, whereas MinCHp localizes at cell poles and pole of new daughter cell in E. coli. In addition, co-immunoprecipitation showed MinC can interact with MinD but not with FtsZ during mid-exponential stage of H. pylori. Altogether, our results show that MinCHp plays a key role in maintaining proper cell morphology and its function differs from those of MinCEc. PMID:23936493

Chiou, Pei-Yu; Luo, Cheng-Hung; Chang, Kai-Chih; Lin, Nien-Tsung

2013-01-01

94

Imaging methods for elemental, chemical, molecular, and morphological analyses of single cells.  

PubMed

Combining elemental, chemical, molecular, and morphological imaging information from individual cells with a lateral resolution well below 1 x 1 microm(2) is the current technological challenge for investigating the smallest dimensions of living systems. In the race for such analytical performance, several techniques have been successfully developed; some use probes to determine given cellular contents whereas others use possible interactions between cellular matter with light or elements for characterization of contents. Morphological techniques providing information about cell dimensions have, when combined with other techniques, also opened the way to quantitative studies. New analytical opportunities are now being considered in cell biology, combining top-performance imaging techniques, applied to the same biosystem, with microscopy (nm-mum range) techniques providing elemental (micro-X-ray fluorescence, particle-induced X-ray emission, secondary-ion mass spectrometry), chemical (Raman, coherent anti-stokes Raman, Fourier-transform infrared, and near-field), molecular (UV-visible confocal and multiphoton), and morphological (AFM, ellipsometry, X-ray phase contrast, digital holography) information. Dedicated cell-culture methods have been proposed for multimodal imaging in vitro and/or ex vivo. This review shows that in addition to UV-fluorescent techniques, the imaging modalities able to provide interesting information about a cell, with high spatial and time resolution, have grown sufficiently to envisage quantitative analysis of chemical species inside subcellular compartments. PMID:20300737

Petibois, Cyril

2010-07-01

95

Asymmetric Cell Division as a Route to Reduction in Cell Length and Change in Cell Morphology in Trypanosomes  

Microsoft Academic Search

African trypanosomes go through at least five developmental stages during their life cycle. The different cellular forms are classified using morphology, including the order of the nucleus, flagellum and kinetoplast along the anterior–posterior axis of the cell, the predominant cell surface molecules and the location within the host. Here, an asymmetrical cell division cycle that is an integral part of

Reuben Sharma; Lori Peacock; Eva Gluenz; Keith Gull; Wendy Gibson; Mark Carrington

2008-01-01

96

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

PubMed

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

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

1991-01-01

97

Cell morphology, ultrastructure, and calcification pattern of Oocardium stratum, a peculiar lotic desmid.  

PubMed

Cell morphology and ultrastructure of the desmid Oocardium stratum and its habitat conditions in two limestone-precipitating spring habitats in the Alps were studied. In spite of specific cell geometry, we found ultrastructural features (nucleus with nucleolus, Golgi apparatus, chloroplast structure, lipid bodies, cell wall texture) closely related to other desmids. The type of the mucilage pore apparatus perforating in high densities extended areas of the cell wall of Oocardium is of the Cosmarium type. Oocardium contrasts to Cosmarium by a peculiar bilateral cell geometry (lateral sphenoid shape) which is combined with a dislocated nucleus. Although the cell features of Oocardium did not differ between the two habitats, different calcification types (rhombohedral calcite versus fascicular-fibrous calcite) and calcification intensities were recorded. The spatial positioning and extension of the Oocardium niches differed considerably between the two springs in spite of high CO(2) oversaturation at both sites. PMID:19455279

Rott, E; Holzinger, A; Gesierich, D; Kofler, W; Sanders, D

2010-07-01

98

Retinal ganglion cells in the Pacific redfin, Tribolodon brandtii dybowski, 1872: morphology and diversity.  

PubMed

We studied the morphology and diversity of retinal ganglion cells in the Pacific redfin, Tribolodon brandtii. These cells were retrogradely labeled with horseradish peroxidase and examined in retinal whole mounts. A sample of 203 cells was drawn with a camera lucida. A total of 19 structural parameters were estimated for each cell, and a variety of clustering algorithms were used to classify the cells. The optimal solution was determined by using silhouette analysis. It was based on three variables associated with dendritic field size and dendrite stratification in the retina. Kruskal-Wallis ANOVA-on-ranks with post hoc Mann-Whitney U tests showed significant pairwise between-cluster differences in two or more of the original variables. In total, eight cell types were discovered. The advantages and drawbacks of the methodology adopted are discussed. The present classification is compared with classifications proposed for other teleosts. PMID:24178784

Pushchin, Igor; Karetin, Yuriy

2014-04-15

99

Conformational switching in ezrin regulates morphological and cytoskeletal changes required for B cell chemotaxis  

PubMed Central

B cell chemotaxis occurs in response to specific chemokine gradients and is critical for homeostasis and immune response. The molecular regulation of B cell membrane-actin interactions during migration is poorly understood. In this study we report a role for ezrin, a member of the membrane-cytoskeleton crosslinking Ezrin-Radixin-Moesin (ERM) proteins, in the regulation of the earliest steps of B cell polarization and chemotaxis. We visualized chemokine-induced changes in murine B cell morphology using scanning electron microscopy, and spatiotemporal dynamics of ezrin in B cells using epifluorescence and total internal reflection microscopy. Upon chemokine stimulation ezrin is transiently dephosphorylated to assume an inactive conformation, and localizes to the lamellipodia. B cells expressing a phosphomimetic conformationally active mutant of ezrin, or those in which ezrin dephosphorylation was pharmacologically inhibited displayed impaired microvillar dynamics, morphological polarization and chemotaxis. Our data suggest a two-fold involvement of ezrin in B cell migration whereby it first undergoes chemokine-induced dephosphorylation to facilitate membrane flexibility, followed by relocalization to the actin-rich lamellipodia for dynamic forward protrusion of the cells. PMID:21339367

Parameswaran, Neetha; Matsui, Ken; Gupta, Neetu

2011-01-01

100

Early postnatal respiratory viral infection alters hippocampal neurogenesis, cell fate, and neuron morphology in the neonatal piglet.  

PubMed

Respiratory viral infections are common during the neonatal period in humans, but little is known about how early-life infection impacts brain development. The current study used a neonatal piglet model as piglets have a gyrencephalic brain with growth and development similar to human infants. Piglets were inoculated with porcine reproductive and respiratory syndrome virus (PRRSV) to evaluate how chronic neuroinflammation affects hippocampal neurogenesis and neuron morphology. Piglets in the neurogenesis study received one bromodeoxyuridine injection on postnatal day (PD) 7 and then were inoculated with PRRSV. Piglets were sacrificed at PD 28 and the number of BrdU+ cells and cell fate were quantified in the dentate gyrus. PRRSV piglets showed a 24% reduction in the number of newly divided cells forming neurons. Approximately 15% of newly divided cells formed microglia, but this was not affected by sex or PRRSV. Additionally, there was a sexual dimorphism of new cell survival in the dentate gyrus where males had more cells than females, and PRRSV infection caused a decreased survival in males only. Golgi impregnation was used to characterize dentate granule cell morphology. Sholl analysis revealed that PRRSV caused a change in inner granule cell morphology where the first branch point was extended further from the cell body. Males had more complex dendritic arbors than females in the outer granule cell layer, but this was not affected by PRRSV. There were no changes to dendritic spine density or morphology distribution. These findings suggest that early-life viral infection can impact brain development. PMID:25176574

Conrad, Matthew S; Harasim, Samantha; Rhodes, Justin S; Van Alstine, William G; Johnson, Rodney W

2015-02-01

101

MORPHOLOGICAL AND PHYSIOLOGICAL STUDIES OF RAT KIDNEY CORTEX SLICES UNDERGOING ISOSMOTIC SWELLING AND ITS REVERSAL: A POSSIBLE MECHANISM FOR OUABAIN-RESISTANT CONTROL OF CELL VOLUME  

EPA Science Inventory

Slices of rat kidney cortex were induced to swell by preincubation at 1C in an isotonic Ringer's solution, and their capacity to reverse swelling, by net extrusion of cellular water, was studied during subsequent incubation at 25C. The recovery from swelling was prevented by the ...

102

Clonally expanded human airway smooth muscle cells exhibit morphological and functional heterogeneity  

PubMed Central

Background Mesenchyme-derived airway cell populations including airway smooth muscle (ASM) cells, fibroblasts and myofibroblasts play key roles in the pathogenesis of airway inflammation and remodeling. Phenotypic and functional characterisation of these cell populations are confounded by their heterogeneity in vitro. It is unclear which mechanisms underlie the creation of these different sub-populations. The study objectives were to investigate whether ASM cells are capable of clonal expansion and if so (i) what proportion possess this capability and (ii) do clonal populations exhibit variation in terms of morphology, phenotype, proliferation rates and pro-relaxant or pro-contractile signaling pathways. Methods Early passage human ASM cells were subjected to single-cell cloning and their doubling time was recorded. Immunocytochemistry was performed to assess localization and levels of markers previously reported to be specifically associated with smooth muscle or fibroblasts. Finally functional assays were used to reveal differences between clonal populations specifically assessing mitogen-induced proliferation and pro-relaxant and pro-contractile signaling pathways. Results Our studies provide evidence that a high proportion (58%) of single cells present within early passage human ASM cell cultures have the potential to create expanded cell populations. Despite being clonally-originated, morphological heterogeneity was still evident within these clonal populations as assessed by the range in expression of markers associated with smooth muscle cells. Functional diversity was observed between clonal populations with 10 ?M isoproterenol-induced cyclic AMP responses ranging from 1.4 - 5.4 fold cf basal and bradykinin-induced inositol phosphate from 1.8 - 5.2 fold cf basal. Conclusion In summary we show for the first time that primary human ASM cells are capable of clonal expansion and that the resulting clonal populations themselves exhibit phenotypic plasticity. PMID:24886333

2014-01-01

103

Influence of Sutherlandia frutescens extracts on cell numbers, morphology and gene expression in MCF7 cells  

Microsoft Academic Search

Sutherlandia frutescens is a well-known South African herbal remedy traditionally used for stomach problems, internal cancers, diabetes, various inflammatory conditions and recently to improve the overall health in cancer and HIV\\/AIDS patients. The influence of crude Sutherlandia frutescens extracts (prepared with 70% ethanol) was investigated on cell numbers, morphology, and gene expression profiles in a MCF-7 human breast adenocarcinoma cell

B. A. Stander; S. Marais; T. J. Steynberg; D. Theron; F. Joubert; C. Albrecht; A. M. Joubert

2007-01-01

104

Biocompatible mesoporous silica nanoparticles with different morphologies for animal cell membrane penetration  

SciTech Connect

Two MCM-41 type, fluorescein-labeled mesoporous silica nanomaterials (MSNs) consisting of spherical and tube-shaped particles were synthesized and characterized. Both materials have hexagonally arranged mesopores with high surface area (>950 m{sup 2}/g) and a narrow distribution of pore diameters. The cellular uptake efficiency and kinetics of both MSNs were measured in a cancer cell line (CHO) and a noncancerous cell line (fibroblasts) by flow cytometry and fluorescence confocal microscopy. The correlation between the particle morphology and aggregation of MSNs to the effectiveness of cellular uptake was investigated. We envision that our study on the morphology dependent endocytosis of MSNs would lead to future developments of efficient transmembrane nanodevices for intracellular sensing and gene/drug delivery.

Trewyn, B.; Nieweg, J.; Zhao, Y,; Lin, V.

2007-11-24

105

Endothelial Cell Morphology and Migration are Altered by Changes in Gravitational Fields  

NASA Technical Reports Server (NTRS)

Endothelial cell migration is important to vascular wall regeneration following injury or stress. However, the mechanism(s) governing this response is not well understood. The microgravity environment of space may complicate the response of these cells to injury. To date, there are no reports in this area. We examined how bovine aortic (BAEC) and pulmonary (BPEC) endothelial cells respond to denudation injury under hypergravity (HGrav) and simulated microgravity (MGrav), using image analysis. In 10% FBS, the migration of confluent BAEC and BPEC into the denuded area was not affected by HGrav or MGrav. However, in low FBS (0.5%), signficantly retarded migration under MGrav, and increased migration under HGrav was found. MGrav also decreased the migration of postconfluent BPEC while HGrav showed no difference. Both MGrav and HGrav strongly decreased the migration of postconfluent BAEC. Also, both cell lines showed significant morphological changes by scanning electron microscopy. These studies indicate that endothelial cell function is affected by changes in gravity.

Melhado, Caroline; Sanford, Gary; Harris-Hooker, Sandra

1997-01-01

106

Platelet storage at 22°C; metabolic, morphologic, and functional studies  

PubMed Central

Platelets stored at 22°C for transfusion purpose have been examined with metabolic, morphologic, and functional studies. Evaluations were made of platelet-rich plasma (PRP) stored for 3-4 days and platelet concentrates (PC) stored for 24 hr. During these periods, lactate accumulated continuously without significant change in platelet count, pH, or plasma glucose. Platelet glycogen fell dramatically both chemically and by electron microscopy, but adenosine triphosphate (ATP), adenosine diphosphate (ADP), and intracellular potassium did not change. After storage, the cell's capacity for glucose utilization through glycolysis, the hexose monophosphate shunt, and the tricarboxylic acid cycle appeared to be intact. Although platelet volume during storage did not change, disc to sphere transformation was observed by phase microscopy. Platelet aggregration with ADP was reduced even after 1 day of storage. After transfusion of stored platelets to thrombocytopenic recipients, recovery of platelet glycogen and capacity for aggregation occurred within 24 hr. In summary, the platelet remains surprisingly intact during the intervals studied; those defects which do develop are reversible in the circulation of a thrombocytopenic recipient if viability has been maintained. A “storage lesion” responsible for loss of viability has not been defined. PMID:5540174

Murphy, Scott; Gardner, Frank H.

1971-01-01

107

In vitro and in vivo studies of an aqueous extract of Matricaria recutita (German chamomile) on the radiolabeling of blood constituents, on the morphology of red blood cells and on the biodistribution of the radiopharmaceutical sodium pertechnetate  

PubMed Central

Background: Natural products might alter the labeling of blood constituents with technetium-99m (99mTc) and these results may be correlated with modifications of the shape of the red blood cells (RBC). The biodistribution of radiopharmaceuticals can be also altered. Objective: This investigation aimed to determine biological effects of an aqueous extract of chamomile (CE). Materials and Methods: To study the effect of the CE on the labeling of blood constituents with 99mTc, in vitro and in vivo assays were performed. The effect of the CE on the morphology of RBC was observed under light microscope. The images were acquired, processed, and the perimeter/area ratio of the RBC determined. To analyze the effect of the CE on biodistribution of the sodium pertechnetate (Na99mTcO4) in Wistar rats, these animals were treated or not with a CE. Na99mTcO4 was injected, the rats were sacrificed, the organs were removed, weighted and percentage of radioactivity/gram calculated. Result: In the in vitro experiment, the radioactivity on blood cells compartment and on insoluble fractions of plasma was diminished. The shape and the perimeter/area ratio of the RBC were altered in in vitro assays. An increase of the percentage of radioactivity of Na99mTcO4 was observed in stomach after in vivo treatment. Conclusion: These results could be due to substances of the CE or by the products of the metabolism of this extract in the animal organism. These findings are examples of drug interaction with a radiopharmaceutical, which could lead to misdiagnosis in clinical practice with unexpected consequences. PMID:24143045

Garcia-Pinto, Angélica B.; Santos-Filho, Sebastiăo D.; Carvalho, Jorge J.; Pereira, Mário J. S.; Fonseca, Adenilson S.; Bernardo-Filho, Mário

2013-01-01

108

Unilateral cryptorchidism induces morphological changes of testes and hyperplasia of Sertoli cells in a dog  

PubMed Central

Cryptorchidism is one of the most common genital defects in dogs. This study investigated the effects of abdominal cryptorchidism on morphology, cell proliferation, and Sertoli cell condition in a dog with spontaneous unilateral cryptorchidism. Elective orchidectomy was performed on the abdominal right testis and the scrotal left testis. Significant reductions in numbers of spermatogonia, spermatocytes, and spermatids were observed in hematoxylin and eosin stained sections of the cryptorchid testis. The size of the epididymal duct was smaller than that of the control testis. Based on Ki67 immunohistochemistry, the proliferative activity of spermatogonia and spermatocytes was significantly decreased in the cryptorchid testis. However, proliferative activity was increased in the epididymal duct. Based on GATA-4 immunohistochemistry, Sertoli cells were relatively resistant to cryptorchidism, and the proliferative activity of Sertoli cells was markedly increased in the cryptorchid testis than in the control testis. These results suggest that spontaneous unilateral cryptorchidism causes morphological defects in spermatogonia and spermatocytes in the testis and changes the size of the efferent ductule of the epididymis. In addition, spontaneous unilateral cryptorchidism increases proliferative activity of Sertoli cells, which may be a predisposing factor for Sertoli cell cancer in cryptorchid testes.

Moon, Joon Ho; Yoo, Dae Young; Jo, Young Kwang; Kim, Geon A; Jung, Hyo Young; Choi, Jung Hoon

2014-01-01

109

Alkaline hemolysis fragility is dependent on cell shape: results from a morphology tracker  

E-print Network

Alkaline hemolysis fragility is dependent on cell shape: results from a morphology tracker Cristian, or for the relationship between cell shape and fragility. Methods: Hydroxide, a porating agent, was generated display increased alkaline hemolysis fragility (shorter lifetimes), providing an explanation

Hughey, Richard

110

Morphology and chirality control self-assembly of sickle hemoglobin inside red blood cells  

NASA Astrophysics Data System (ADS)

Sickle cells exhibit abnormal morphology and membrane mechanics in the deoxygenated state due to the polymerization of the interior sickle hemoglobin (HbS). In this study, the dynamics of self-assembly behavior of HbS in solution and corresponding induced cell morphologies have been investigated by dissipative particle dynamics approach. A coarse-grained HbS model, which contains hydrophilic and hydrophobic particles, is constructed to match the structural properties and physical description (including crowding effects) of HbS. The hydrophobic interactions are shown to be necessary with chirality being the main driver for the formation of HbS fibers. In the absence of chain chirality, only the self-assembled small aggregates are observed whereas self-assembled elongated step-like bundle microstructures appear when we consider the chain chirality. Several typical cell morphologies (sickle, granular, elongated shapes), induced by the growth of HbS fibers, are revealed and their deviations from the biconcave shape are quantified by the asphericity and elliptical shape factors.

Li, Xuejin; Lei, Huan; Caswell, Bruce; Karniadakis, George

2012-02-01

111

Retinoic Acid Improves Morphology of Cultured Peritoneal Mesothelial Cells from Patients Undergoing Dialysis  

PubMed Central

Patients undergoing continuous ambulatory peritoneal dialysis are classified according to their peritoneal permeability as low transporter (low solute permeability) or High transporter (high solute permeability). Factors that determine the differences in permeability between them have not been fully disclosed. We investigated morphological features of cultured human peritoneal mesothelial cells from low or high transporter patients and its response to All trans retinoic Acid (ATRA, vitamin A active metabolite), as compared to non-uremic human peritoneal mesothelial cells. Control cells were isolated from human omentum. High or low transporter cells were obtained from dialysis effluents. Cells were cultured in media containing ATRA (0, 50, 100 or 200 nM). We studied length and distribution of microvilli and cilia (scanning electron microscopy), epithelial (cytokeratin, claudin-1, ZO-1 and occludin) and mesenchymal (vimentin and ?-smooth muscle actin) transition markers by immunofluorescence and Western blot, and transforming growth factor ?1 expression by Western blot. Low and high transporter exhibited hypertrophic cells, reduction in claudin-1, occludin and ZO-1 expression, cytokeratin and vimentin disorganization and positive ?-smooth muscle actin label. Vimentin, ?-smooth muscle actin and transforming growth factor- ?1 were overexpressed in low transporter. Ciliated cells were diminished in low and high transporters. Microvilli number and length were severely reduced in high transporter. ATRA reduced hypertrophic cells number in low transporter. It also improved cytokeratin and vimentin organization, decreased vimentin and ?-smooth muscle actin expression, and increased claudin 1, occludin and ZO-1 expression, in low and high transporter. In low transporter, ATRA reduced transforming growth factor-?1 expression. ATRA augmented percentage of ciliated cells in low and high transporter. It also augmented cilia length in high transporter. Alterations in structure, epithelial mesenchymal markers and transforming growth factor-?1expression were differential between low and high transporter. Beneficial effects of ATRA were improved human peritoneal mesothelial cells morphology tending to normalize structures. PMID:24223992

Retana, Carmen; Sanchez, Elsa I.; Gonzalez, Sirenia; Perez-Lopez, Alejandro; Cruz, Armando; Lagunas-Munoz, Jesus; Alfaro-Cruz, Carmen; Vital-Flores, Socorro; Reyes, José L.

2013-01-01

112

Morphological Study of Insoluble Organic Matter Residues from Primitive  

NASA Technical Reports Server (NTRS)

Insoluble organic matter (IOM) constitutes a major proportion, 70-99%, of the total organic carbon found in primitive chondrites [1, 2]. One characteristic morphological component of IOM is nanoglobules [3, 4]. Some nanoglobules exhibit large N-15 and D enrichments relative to solar values, indicating that they likely originated in the ISM or the outskirts of the protoplanetary disk [3]. A recent study of samples from the Tagish Lake meteorite with varying levels of hydrothermal alteration suggest that nanoglobule abundance decreases with increasing hydrothermal alteration [5]. The aim of this study is to further document the morphologies of IOM from a range of primitive chondrites in order to determine any correlation of morphology with petrographic grade and chondrite class that could constrain the formation and/or alteration mechanisms.

Changela, H. G.; Stroud, R. M.; Peeters, Z.; Nittler, L. R.; Alexander, C. M. O'D.; DeGregorio, B. T.; Cody, G. D.

2012-01-01

113

Real-Time Sensing of Cell Morphology by Infrared Waveguide Spectroscopy  

PubMed Central

We demonstrate that a live epithelial cell monolayer can act as a planar waveguide. Our infrared reflectivity measurements show that highly differentiated simple epithelial cells, which maintain tight intercellular connectivity, support efficient waveguiding of the infrared light in the spectral region of 1.4–2.5 µm and 3.5–4 µm. The wavelength and the magnitude of the waveguide mode resonances disclose quantitative dynamic information on cell height and cell-cell connectivity. To demonstrate this we show two experiments. In the first one we trace in real-time the kinetics of the disruption of cell-cell contacts induced by calcium depletion. In the second one we show that cell treatment with the PI3-kinase inhibitor LY294002 results in a progressive decrease in cell height without affecting intercellular connectivity. Our data suggest that infrared waveguide spectroscopy can be used as a novel bio-sensing approach for studying the morphology of epithelial cell sheets in real-time, label-free manner and with high spatial-temporal resolution. PMID:23119025

Lirtsman, Vladislav; Golosovsky, Michael; Davidov, Dan; Aroeti, Benjamin

2012-01-01

114

ANALYSES OF THE INTERACTIONS WITHIN BINARY MIXTURES OF CARCINOGENIC PAHS USING MORPHOLOGICAL CELL TRANSFORMATION OF C3H10T1/2CL8 CELLS  

EPA Science Inventory

ANALYSES OF THE INTERACTIONS WITHIN BINARY MIXTURES OF CARCINOGENIC PAHS USING MORPHOLOGICAL CELL TRANSFORMATION OF C3HIOT1/2 CL8 CELLS. Studies of defined mixtures of carcinogenic polycyclic aromatic hydrocarbons (PAH) have identified three major categories of interacti...

115

Cell-wall morphology correlated with vertical migration in the non-motile marine dinoflagellate Pyrocystis noctiluca  

Microsoft Academic Search

We report an ultrastructural study of the morphological changes in cells of the marine dinoflagellate Pyrocystis noctiluca Murray, which correlate with its vertical migration pattern. Cells alternate between a large, highly vacuolated, positively\\u000a buoyant, vegetative cyst surrounded by a dinosporin-containing wall and a smaller, more compact, negatively buoyant, cellulose-bounded\\u000a cell. The cyst wall is composed of two layers: a thin

K. S. Seo; L. Fritz

2000-01-01

116

UV-C pre-adaptation of Salmonella: effect on cell morphology and membrane fatty acids composition.  

PubMed

The present study was carried out to evaluate the effects of ultraviolet radiations (UV-C) on the fatty acids composition of three serovars of Salmonella: S. typhimurium, S. hadar and S. zanzibar. Results obtained show that UV-C treatment increases significantly (P ? 0.05) the percentage of cyclic fatty acids. The atomic force microscopy was used to study the morphology and cell surface of irradiated strains. Results show that UV-C rays induce morphological changes and alter the bacterial cell surface (presence of grooves and irregularities). PMID:24092393

Maâlej, Lobna; Chatti, Abdelwaheb; Khefacha, Sana; Salma, Kloula; Gottardi, David; Vannini, Lucia; Guerzoni, Maria Elizabetta; Hassen, Abdennaceur

2014-03-01

117

Morphological Priming by Itself: A Study of Portuguese Conjugations  

ERIC Educational Resources Information Center

Does the language processing system make use of abstract grammatical categories and representations that are not directly visible from the surface form of a linguistic expression? This study examines stem-formation processes and conjugation classes, a case of "pure" morphology that provides insight into the role of grammatical structure in…

Verissimo, Joao; Clahsen, Harald

2009-01-01

118

Dendritic Morphology of Caudal Periaqueductal Gray Projecting Retinal Ganglion Cells in Mongolian Gerbil (Meriones unguiculatus)  

PubMed Central

In this study we investigated the morphological features of the caudal periaqueductal gray (cPAG)-projecting retinal ganglion cells (RGCs) in Mongolian gerbils using retrograde labeling, in vitro intracellular injection, confocal microscopy and three-dimensional reconstruction approaches. cPAG-projecting RGCs exhibit small somata (10–17 µm) and irregular dendritic fields (201–298 µm). Sizes of somata and dendritic fields do not show obvious variation at different distance from the optic disk (eccentricity). Dendrites are moderately branched. Morphological analysis (n?=?23) reveals that cPAG-projecting RGCs ramified in sublamina a and b in the inner plexiform layer. These cells exhibit different stratification patterns based on the thickness of dendritic bands in sublaminas a and b: majority of analyzed cells (16 out of 23) have two bands of arborizations share similar thickness. The rest of analyzed cells (7 out of 23) exhibit thinner band in sublamina a than in sublamina b. Together, the present study suggests that cPAG of Mongolian gerbil could receive direct retinal inputs from two types of bistratified RGCs. Furthermore, a small subset of melanopsin-expressing RGCs (total 41 in 6 animals) is shown to innervate the rostral PAG (rPAG). Functional characteristics of these non-visual center projecting RGCs remain to be determined. PMID:25054882

Ren, Chaoran; Pu, Mingliang; Cui, Qi; So, Kwok-Fai

2014-01-01

119

Action potential morphology of human induced pluripotent stem cell-derived cardiomyocytes does not predict cardiac chamber specificity and is dependent on cell density.  

PubMed

Previous studies investigating human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) have proposed the distinction of heart chamber-specific (atrial, ventricular, pacemaker) electrophysiological phenotypes based on action potential (AP) morphology. This suggestion has been based on data acquired using techniques that allow measurements from only a small number of cells and at low seeding densities. It has also been observed that density of culture affects the properties of iPSC-CMs. Here we systematically analyze AP morphology from iPSC-CMs at two seeding densities: 60,000 cells/well (confluent monolayer) and 15,000 cells/well (sparsely-seeded) using a noninvasive optical method. The confluent cells (n = 360) demonstrate a series of AP morphologies on a normally distributed spectrum with no evidence for specific subpopulations. The AP morphologies of sparsely seeded cells (n = 32) displayed a significantly different distribution, but even in this case there is no clear evidence of chamber-specificity. Reduction in gap junction conductance using carbenoxolone only minimally affected APD distribution in confluent cells. These data suggest that iPSC-CMs possess a sui generis AP morphology, and when observed in different seeding densities may encompass any shape including those resembling chamber-specific subtypes. These results may be explained by different functional maturation due to culture conditions. PMID:25564842

Du, David T M; Hellen, Nicola; Kane, Christopher; Terracciano, Cesare M N

2015-01-01

120

Effects of plasma treatment to nanofibers on initial cell adhesion and cell morphology.  

PubMed

Poly-L-lactic acid (PLLA) nanofibers were fabricated by electrospinning and treated with O2 plasma. The surface properties of PLLA nanofibers before and after plasma treatment were characterized by water contact angle measurement and X-ray photoelectron spectroscopy (XPS). It was found that the hydrophilicity of PLLA nanofibers was improved and the amount of oxygen-containing groups increased after plasma treatment. Initial cell adhesion was evaluated by cell capture efficiency based on the cell count method. The results showed that initial porcine mesenchymal stem cells (pMSCs) adhesion to plasma-treated nanofibers was significantly enhanced. Moreover, the morphology of pMSCs on PLLA nanofibers (PLLA NFS) and plasma-treated PLLA nanofibers (P-PLLA NFS) were observed by scanning electron microscope (SEM) after 10 min, 20 min, 30 min and 60 min cell adhesion. It was found that plasma treatment to electrospun nanofibers had a great effect on pMSCs morphology at earlier time points. Therefore, plasma treatment is an efficient surface modification strategy to improve cell adhesion in earlier culture time intervals. It may be a promising method in the design of novel tissue-engineered scaffolds. PMID:24060934

Liu, Wei; Zhan, Jianchao; Su, Yan; Wu, Tong; Wu, Chunchen; Ramakrishna, Seeram; Mo, Xiumei; Al-Deyab, Salem S; El-Newehy, Mohamed

2014-01-01

121

Atomic force microscopy analysis of central nervous system cell morphology on silicon carbide and diamond substrates.  

PubMed

Brain machine interface (BMI) devices offer a platform that can be used to assist people with extreme disabilities, such as amyotrophic lateral sclerosis (ALS) and Parkinson's disease. Silicon (Si) has been the material of choice used for the manufacture of BMI devices due to its mechanical strength, its electrical properties and multiple fabrication techniques; however, chronically implanted BMI devices have usually failed within months of implantation due to biocompatibility issues and the fact that Si does not withstand the harsh environment of the body. Single crystal cubic silicon carbide (3C-SiC) and nanocrystalline diamond (NCD) are semiconductor materials that have previously shown good biocompatibility with skin and bone cells. Like Si, these materials have excellent physical characteristics, good electrical properties, but unlike Si, they are chemically inert. We have performed a study to evaluate the general biocompatibility levels of all of these materials through the use of in vitro techniques. H4 human neuroglioma and PC12 rat pheochromocytoma cell lines were used for the study, and polystyrene (PSt) and amorphous glass were used as controls or for morphological comparison. MTT [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide] assays were performed to determine general cell viability with each substrate and atomic force microscopy (AFM) was used to quantify the general cell morphology on the substrate surface along with the substrate permissiveness to lamellipodia extension. 3C-SiC was the only substrate tested to have good viability and superior lamellipodia permissiveness with both cell lines, while NCD showed a good level of viability with the neural H4 line but a poor viability with the PC12 line and lower permissiveness than 3C-SiC. Explanations pertaining to the performance of each substrate with both cell lines are presented and discussed along with future work that must be performed to further evaluate specific cell reactions on these substrates. PMID:19585542

Frewin, C L; Jaroszeski, M; Weeber, E; Muffly, K E; Kumar, A; Peters, M; Oliveros, A; Saddow, S E

2009-01-01

122

Chemical Effects in Solution on the Formation of Film Morphology in Bulk Heterojunction Organic Solar Cells  

NASA Astrophysics Data System (ADS)

A novel method to control the active layer morphology of bulk heterojunction(BHJ) organic solar cells will be presented in this study. The effect of solvent quality, chemical effect in solution, on the morphology of poly(3-hexylthiophene) (P3HT):phenyl-C61-butyric acid methyl ester (PCBM) active layer has been investigated. The solubility of solvent can be controlled by mixing other types of additional solvents (additives) to the P3HT:PCBM blend solution, which could adjust the association and/or solvation characteristics for both P3HT and PCBM solutes in mixed solvents. As a result, the control over the solubility has a definitive effect on the film morphology. We report a new additive, 2-chlorophenol, which could drive P3HT to have more association character and, PCBM to have more solvation character in the mixed solvent. Higher P3HT crystallinity was achieved due to more association character in the presence of 2-chlorophenol. Also, the higher solvation character of PCBM leads to the reduced size of PCBM agglomerates, as confirmed by SANS measurements. Based on these results, P3HT:PCBM BHJ solar cell devices were fabricated, with maximum power conversion efficiency of 3.24%, which is 43% enhancement when compared with the reference.

Kuk Koh, Jong; Choi, Won Tae; Char, Kookheon

2013-03-01

123

In vitro effects of Sutherlandia frutescens water extracts on cell numbers, morphology, cell cycle progression and cell death in a tumorigenic and a non-tumorigenic epithelial breast cell line  

Microsoft Academic Search

Sutherlandia frutescens is a South African herb traditionally used for internal cancers, diabetes, a variety of inflammatory conditions and recently to improve the overall health in cancer and HIV\\/AIDS patients. The in vitro effects of S. frutescens extracts were evaluated on cell numbers, morphology, cell cycle progression and cell death. Dose-dependent studies (2–10mg\\/ml) revealed a decrease in malignant cell numbers

Andre Stander; Sumari Marais; Voula Stivaktas; Christiaan Vorster; Carl Albrecht; Mona-Liza Lottering; Annie M. Joubert

2009-01-01

124

Double-Staining Method for Differentiation of Morphological Changes and Membrane Integrity of Campylobacter coli Cells  

PubMed Central

We developed a double-staining procedure involving NanoOrange dye (Molecular Probes, Eugene, Oreg.) and membrane integrity stains (LIVE/DEAD BacLight kit; Molecular Probes) to show the morphological and membrane integrity changes of Campylobacter coli cells during growth. The conversion from a spiral to a coccoid morphology via intermediary forms and the membrane integrity changes of the C. coli cells can be detected with the double-staining procedure. Our data indicate that young or actively growing cells are mainly spiral shaped (green-stained cells), but older cells undergo a degenerative change to coccoid forms (red-stained cells). Club-shaped transition cell forms were observed with NanoOrange stain. Chlorinated drinking water affected the viability but not the morphology of C. coli cells. PMID:12324366

Alonso, Jose L.; Mascellaro, Salvatore; Moreno, Yolanda; Ferrús, María A.; Hernández, Javier

2002-01-01

125

Double-staining method for differentiation of morphological changes and membrane integrity of Campylobacter coli cells.  

PubMed

We developed a double-staining procedure involving NanoOrange dye (Molecular Probes, Eugene, Oreg.) and membrane integrity stains (LIVE/DEAD BacLight kit; Molecular Probes) to show the morphological and membrane integrity changes of Campylobacter coli cells during growth. The conversion from a spiral to a coccoid morphology via intermediary forms and the membrane integrity changes of the C. coli cells can be detected with the double-staining procedure. Our data indicate that young or actively growing cells are mainly spiral shaped (green-stained cells), but older cells undergo a degenerative change to coccoid forms (red-stained cells). Club-shaped transition cell forms were observed with NanoOrange stain. Chlorinated drinking water affected the viability but not the morphology of C. coli cells. PMID:12324366

Alonso, Jose L; Mascellaro, Salvatore; Moreno, Yolanda; Ferrús, María A; Hernández, Javier

2002-10-01

126

Are morphological criteria sufficient for the identification of circulating tumor cells in renal cancer?  

PubMed Central

Background Single circulating tumor cells (CTCs) or circulating tumor microemboli (CTMs) are potential biomarkers of renal cell cancer (RCC), however studies of CTCs/CTMs in RCC are limited. In this pilot study we aimed to evaluate a novel blood filtration technique suited for cytomorphological classification, immunocytochemical and molecular characterization of filtered, so called circulating non-hematologic cells (CNHCs) - putative CTCs/CTMs - in patients with RCC. Methods Blood of 40 patients with renal tumors was subjected to ScreenCell® filtration. CNHCs were classified according to cytomorphological criteria. Immunocytochemical analysis was performed with antibodies against CD45, CD31 and carbonic anhydrase IX (CAIX, a RCC marker). DNA of selected CNHCs and respective primary tumors was analysed by array-CGH. Results CNHC-clusters with malignant or uncertain malignant cytomorphological features - putative CTMs - were negative for CD45, positive for CD31, while only 6% were CAIX positive. Array-CGH revealed that 83% of malignant and uncertain malignant cells did represent with a balanced genome whereas 17% presented genomic DNA imbalances which did not match the aberrations of the primary tumors. Putative single CTCs were negative for CD45, 33% were positive for CD31 and 56% were positive for CAIX. Conclusions The majority of CNHC-clusters, putative CTMs, retrieved by ScreenCell® filtration may be of endothelial origin. Morphological criteria seem to be insufficient to distinguish malignant from non-malignant cells in renal cancer. PMID:24044779

2013-01-01

127

A Screen for Morphological Complexity Identifies Regulators of Switch-like Transitions between Discrete Cell Shapes  

PubMed Central

The way in which cells adopt different morphologies is not fully understood. Cell shape could be a continuous variable or restricted to a set of discrete forms. We developed quantitative methods to describe cell shape and show that Drosophila hemocytes in culture are a heterogeneous mixture of five discrete morphologies. In an RNAi screen of genes affecting the morphological complexity of heterogeneous populations, we found that most genes regulate the transition between discrete shapes rather than generating new morphologies. In particular, we identified a subset of genes, including the tumour suppressor PTEN, that decrease the heterogeneity of the population leading to populations enriched in rounded or elongated forms. We show that these genes have a highly conserved function as regulators of cell shape in both mouse and human metastatic melanoma cells. PMID:23748611

Yin, Zheng; Sadok, Amine; Sailem, Heba; McCarthy, Afshan; Xia, Xiaofeng; Li, Fuhai; Garcia, Mar Arias; Evans, Louise; Barr, Alexis; Perrimon, Norbert; Marshall, Christopher J; Wong, Stephen T.C.; Bakal, Chris

2013-01-01

128

Using wavelet denoising and mathematical morphology in the segmentation technique applied to blood cells images.  

PubMed

Accurate image segmentation is used in medical diagnosis since this technique is a noninvasive pre-processing step for biomedical treatment. In this work we present an efficient segmentation method for medical image analysis. In particular, with this method blood cells can be segmented. For that, we combine the wavelet transform with morphological operations. Moreover, the wavelet thresholding technique is used to eliminate the noise and prepare the image for suitable segmentation. In wavelet denoising we determine the best wavelet that shows a segmentation with the largest area in the cell. We study different wavelet families and we conclude that the wavelet db1 is the best and it can serve for posterior works on blood pathologies. The proposed method generates goods results when it is applied on several images. Finally, the proposed algorithm made in MatLab environment is verified for a selected blood cells. PMID:23458301

Boix, Macarena; Cantó, Begońa

2013-04-01

129

PDMS substrate stiffness affects the morphology and growth profiles of cancerous prostate and melanoma cells.  

PubMed

A deep understanding of the interaction between cancerous cells and surfaces is particularly important for the design of lab-on-chip devices involving the use of polydimethylsiloxane (PDMS). In our studies, the effect of PDMS substrate stiffness on mechanical properties of cancerous cells was investigated in conditions where the PDMS substrate is not covered with any of extracellular matrix proteins. Two human prostate cancer (Du145 and PC-3) and two melanoma (WM115 and WM266-4) cell lines were cultured on two groups of PDMS substrates that were characterized by distinct stiffness, i.e. 0.75 ± 0.06 MPa and 2.92 ± 0.12 MPa. The results showed the strong effect on cellular behavior and morphology. The detailed analysis of chemical and physical properties of substrates revealed that cellular behavior occurs only due to substrate elasticity. PMID:25460399

Prauzner-Bechcicki, Szymon; Raczkowska, Joanna; Madej, Ewelina; Pabijan, Joanna; Lukes, Jaroslav; Sepitka, Josef; Rysz, Jakub; Awsiuk, Kamil; Bernasik, Andrzej; Budkowski, Andrzej; Lekka, Ma?gorzata

2015-01-01

130

Morphological priming during language switching: an ERP study  

PubMed Central

Bilingual language control (BLC) is a much-debated issue in recent literature. Some models assume BLC is achieved by various types of inhibition of the non-target language, whereas other models do not assume any inhibitory mechanisms. In an event-related potential (ERP) study involving a long-lag morphological priming paradigm, participants were required to name pictures and read aloud words in both their L1 (Dutch) and L2 (English). Switch blocks contained intervening L1 items between L2 primes and targets, whereas non-switch blocks contained only L2 stimuli. In non-switch blocks, target picture names that were morphologically related to the primes were named faster than unrelated control items. In switch blocks, faster response latencies were recorded for morphologically related targets as well, demonstrating the existence of morphological priming in the L2. However, only in non-switch blocks, ERP data showed a reduced N400 trend, possibly suggesting that participants made use of a post-lexical checking mechanism during the switch block. PMID:25566022

Lensink, Saskia E.; Verdonschot, Rinus G.; Schiller, Niels O.

2014-01-01

131

Morphological Characterization of Bushy Cells and Their Inputs in the Laboratory Mouse (Mus musculus) Anteroventral Cochlear Nucleus  

PubMed Central

Spherical and globular bushy cells of the AVCN receive huge auditory nerve endings specialized for high fidelity neural transmission in response to acoustic events. Recent studies in mice and other rodent species suggest that the distinction between bushy cell subtypes is not always straightforward. We conducted a systematic investigation of mouse bushy cells along the rostral-caudal axis in an effort to understand the morphological variation that gives rise to reported response properties in mice. We combined quantitative light and electron microscopy to investigate variations in cell morphology, immunostaining, and the distribution of primary and non-primary synaptic inputs along the rostral-caudal axis. Overall, large regional differences in bushy cell characteristics were not found; however, rostral bushy cells received a different complement of axosomatic input compared to caudal bushy cells. The percentage of primary auditory nerve terminals was larger in caudal AVCN, whereas non-primary excitatory and inhibitory inputs were more common in rostral AVCN. Other ultrastructural characteristics of primary auditory nerve inputs were similar across the rostral and caudal AVCN. Cross sectional area, postsynaptic density length and curvature, and mitochondrial volume fraction were similar for axosomatic auditory nerve terminals, although rostral auditory nerve terminals contained a greater concentration of synaptic vesicles near the postsynaptic densities. These data demonstrate regional differences in synaptic organization of inputs to mouse bushy cells rather than the morphological characteristic of the cells themselves. PMID:23991186

Lauer, Amanda M.; Connelly, Catherine J.; Graham, Heather; Ryugo, David K.

2013-01-01

132

Nutr Cancer . Author manuscript Flavonoid-induced morphological modifications of endothelial cells  

E-print Network

, apigenin, quercetin, baicalein, fisetin, and galangin. Important SAR for cytotoxicity included the C2-C3 double bond and 3 ,4 -dihydroxylation. Concerning the morphological effects on EC, only fisetin hydroxylation at C-7 and C-4 . Fisetin, the most active agent, presented cell morphology that was distinct

Paris-Sud XI, Université de

133

Effect of DTPP-mediated photodynamic therapy on cell morphology, viability, cell cycle, and cytotoxicity in a murine lung adenocarcinoma cell line.  

PubMed

Photodynamic therapy (PDT) involves the administration and activation of photosensitizing reagents in cancer tissues to induce cytotoxicity. Here we examined the effects of 5-5- (4-N, N-diacetoxylphenyl)-10,15,20- tetraphenylporphyrin (DTPP) -mediated PDT on cell morphology, viability, cell cycle, and cytotoxicity in a murine lung adenocarcinoma cell line. LA795 murine lung adenocarcinoma cell line was used in the study, with cellular uptake of DTPP being quantified by a UV-visible spectrophotometer. The subcellular localization of DTPP was detected by confocal laser scanning microscopy, alteration of cell morphology after PDT was observed by an inverted light microscope, and late-stage apoptosis was examined by terminal dUTP nick end labeling (TUNEL) . The effects of influencing factors on cytotoxicity of PDT in LA795 cells was investigated with varying concentrations of DTPP, energy densities, power densities, and antioxidants by 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Effects of PDT on cell cycle and plasma membrane integrity were studied by flow cytometry analysis. The uptake of DTPP by LA795 cells reached maximum after incubation for 24 h. Confocal laser scanning microscopy showed that DTPP was mainly in the mitochondrion, and slight localization was detected in the lysosomes. Cellular inhibitory effects increased with increased irradiation dose and DTPP concentration, while unactivated DTPP had low toxicity. Flow cytometry analysis revealed that DTPP-PDT-treated cells showed S phase arrest. Cell membrane damage initiation, repair, and irreversible damage were observed at 2, 4, and 5 h after DTPP-PDT , respectively. Together, our results demonstrated cell apoptosis, compromised viability, and cell cycle S phase arrest of LA795 in response to DTPP-PDT , while no effect on the lung cancer cells was observed with irradiation or photosensitizer treatment alone. PMID:25118661

Liu, Jianhua; Zheng, Liqing; Li, Yingxin; Zhang, Zhihua; Zhang, Li; Shen, Lixia; Zhang, Xiulong; Qiao, Haixia

2015-01-01

134

DIFFERENCES IN MORPHOLOGICAL AND CELL WALL TRAITS OF ALFALFA PLANTS SELECTED FOR DIVERGENT STEM IN VITRO FIBER DIGESTIBILITY  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study compared alfalfa clones identified as either low or high rapid (16 h), or low or high potential (96 h) stem in vitro neutral detergent fiber digestibility (IVNDFD) for stem fiber, cell wall, and morphology traits. Five clones of each selection group were grown in replicated field plots at...

135

Transitional cardiac cells of the conductive system of the dog heart. Distinguishing morphological and electrophysiological features.  

PubMed

Cardiac cells with distinctive electrophysiological and morphological features were found at the junctional region between Purkinje and ventricular cells of the dog heart. The electrophysiological exploration of these "transitional" cells revealed action potentials markedly different in configuration from those generated by Purkinje or by ventricular cells. The impaled cardiac cells which generated transitional action potentials were identified in serial sections and studied with the light and the electron microscopes. The transitional cells were found to be characterized cytologically by: (a) their subendocardial location, (b) their small diameter, (c) the absence of T system and sarcoplasmic reticulum, and (d) the lack of intercalated discs under the light microscope and the sparsity of specialized intercellular junctions under the electron microscope. Purkinje, transitional, and ventricular cells were found to be joined by gap junctions permeable to lanthanum. A quantitative difference in the extent and distribution of specialized intercellular junctions may be one of the factors responsible for the slow velocity of conduction characteristic of the Purkinje-ventricular junctional region. PMID:5513552

Martinez-Palomo, A; Alanis, J; Benitez, D

1970-10-01

136

AMPK knockdown in placental trophoblast cells results in altered morphology and function.  

PubMed

The placenta is a transient organ that develops upon the initiation of pregnancy and is essential for embryonic development and fetal survival. The rodent placenta consists of distinct lineages and includes cell types that are analogous to those that make up the human placenta. Trophoblast cells within the labyrinth layer, which lies closest to the fetus, fuse and come in contact with maternal blood, thus facilitating nutrient and waste exchange between the mother and the baby. Abnormalities of the placenta may occur as a result of cellular stress and have been associated with pregnancy-associated disorders: such as preeclampsia, intrauterine growth restriction, and placental insufficiency. Cellular stress has also been shown to alter proliferation and differentiation rates of trophoblast cells. This stress response is important for cell survival and ensures continued placental functionality. AMP-activated protein kinase is an important sensor of cellular metabolism and stress. To study the role of AMPK in the trophoblast cells, we used RNA interference to simultaneously knockdown levels of both the AMPK alpha isoforms, AMPK?1 and AMPK?2. SM10 trophoblast progenitor cells were transduced with AMPK?1/2 shRNA and stable clones were established to analyze the effects of AMPK knockdown on important cellular functions. Our results indicate that a reduction in AMPK levels causes alterations in cell morphology, growth rate, and nutrient transport, thus identifying an important role for AMPK in the regulation of placental trophoblast differentiation. PMID:25003940

Carey, Erica A K; Albers, Renee E; Doliboa, Savannah R; Hughes, Martha; Wyatt, Christopher N; Natale, David R C; Brown, Thomas L

2014-12-01

137

Shape-memory-actuated change in scaffold fiber alignment directs stem cell morphology.  

PubMed

Tissue engineering scaffolds have traditionally been static physical structures poorly suited to mimicking the complex dynamic behavior of in vivo microenvironments. Here we present a thermoresponsive scaffold that can be programmed to change macroscopic shape and microscopic architecture during cell culture. The scaffold, which was prepared by electrospinning a shape memory polymer (SMP), was used to test the hypothesis that a shape-memory-actuated change in scaffold fiber alignment could be used to control the behavior of attached and viable cells. To test this hypothesis, we stretched an SMP scaffold of randomly oriented fibers and fixed the scaffold in a temporary but stable elongated shape in which fibers were aligned by the strain. Following seeding and culture of human adipose-derived stem cells on the strain-aligned scaffold, the scaffold was triggered to transition back to its initial shape and random fiber orientation via shape memory actuation using a cytocompatible temperature increase. We found that cells preferentially aligned along the fiber direction of the strain-aligned scaffold before shape memory actuation. After shape memory actuation, cells remained attached and viable but lost preferential alignment. These results demonstrate that shape-memory-actuated changes in scaffold fiber alignment can be achieved with attached and viable cells and can control cell morphological behavior. The incorporation of shape memory into cytocompatible scaffolds is anticipated to facilitate the development, delivery and functionality of tissue engineering scaffolds and the in vitro and in vivo study and application of mechanobiology. PMID:23851156

Tseng, Ling-Fang; Mather, Patrick T; Henderson, James H

2013-11-01

138

Modeling Study of Fruit Morphological Formation in Melon  

Microsoft Academic Search

Modeling of fruit morphological formation in melon is important for realizing virtual and digital plant growth. The objective of this study was to characterize the changes in patterns of fruit growth characters during plant development. In cultivar experiments, a high-resolution wireless vision sensor network has been developed to realize non-contact automatic uninterrupted measurement of the fruit shape micro-change (fruit size,

Li-ying CHANG; Qing-liang NIU; Yu-bin MIAO; San-peng HE; Chong CUI; Dan-feng HUANG

2011-01-01

139

Morphologic and immunocytochemical performances of effusion cell blocks prepared using 3 different methods.  

PubMed

With increased use of the ThinPrep method for nongynecologic specimens, cell blocks are more commonly prepared by harvesting cells that are fixed in CytoLyt solution. The current study compared morphologic and immunocytochemical performance of effusion cell blocks prepared using CytoLyt-prefixed thrombin clot (CTC) with plasma thrombin clot (PT) and HistoGel (HG) preparation. The study included a total of 25 malignant or benign serous fluids. Three individual cell block materials were simultaneously prepared from each of the 25 effusion specimens using the CTC, PT, or HG method. H&E staining and immunostaining for pancytokeratin (pan-CK), carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA), B72.3, HBME-1, estrogen receptor (ER), progesterone receptor (PR), CD45, CD20, and CD3 were then performed. The CTC preparation revealed compatible cellularity and good cellular details. In addition, CTC cell blocks revealed a similar percentage of cells with positive immunostaining along with the strongest intensity and the least background staining. The CTC method can be used reliably as an adjunct to other preparation techniques. PMID:23355202

Jing, Xin; Li, Qing Kay; Bedrossian, Ursula; Michael, Claire W

2013-02-01

140

Early diagnosis of intravascular large B-cell lymphoma: clues from routine blood smear morphologic findings.  

PubMed

Intravascular large B-cell lymphoma (IVLBCL) is a mature B-cell neoplasm characterized by malignant lymphoid cells within the lumina of blood vessels and capillaries. Given its varied and nonspecific clinical manifestation, this aggressive disease is often not diagnosed until an advanced clinical stage or even at autopsy. This case highlights a patient presenting with autoimmune hemolytic anemia (AIHA) and fevers. Atypical circulating cells on a screening peripheral smear lead to flow cytometric studies highlighting an increase in large, light chain restricted CD20 positive cells. A diagnostic bone marrow biopsy was performed and trephine cores demonstrated predominantly intrasinusoidal lymphoma cells. In conjunction with additional immunophenotypic data, these studies strongly supported a diagnosis of IVLBCL. Judicious use of flow cytometry and morphology resulted in an early-stage diagnosis and likely contributed to the patient's current complete remission status following anti-CD20 therapy. Differential diagnoses for this presentation are discussed in light of serologic, immunophenotypic, histologic, and cytogenetic findings. PMID:25051078

Patel, Sagar S; Aasen, Garth A; Dolan, Michelle M; Linden, Michael A; McKenna, Robert W; Rudrapatna, Venkatesh K; Trottier, Bryan J; Drawz, Sarah M

2014-01-01

141

Morphological Analysis of Human Induced Pluripotent Stem Cells During Induced Differentiation and Reverse Programming  

PubMed Central

Abstract The fine analysis of cell components during the generation of pluripotent cells and their comparison to bone fide human embryonic stem cells (hESCs) are valuable tools to understand their biological behavior. In this report, human mesenchymal cells (hMSCs) generated from the human ES cell line H9, were reprogrammed back to induced pluripotent state using Oct-4, Sox2, Nanog, and Lin28 transgenes. Human induced pluripotent stem cells (hIPSCs) were analyzed using electron microscopy and compared with regard to the original hESCs and the hMSCs from which they were derived. This analysis shows that hIPSCs and the original hESCs are morphologically undistinguishable but differ from the hMSCs with respect to the presence of several morphological features of undifferentiated cells at both the cytoplasmic (ribosomes, lipid droplets, glycogen, scarce reticulum) and nuclear levels (features of nuclear plasticity, presence of euchromatin, reticulated nucleoli). We show that hIPSC colonies generated this way presented epithelial aspects with specialized junctions highlighting morphological criteria of the mesenchymal–epithelial transition in cells engaged in a successful reprogramming process. Electron microscopic analysis revealed also specific morphological aspects of partially reprogrammed cells. These results highlight the valuable use of electron microscopy for a better knowledge of the morphological aspects of IPSC and cellular reprogramming. PMID:25371857

Magniez, Aurélie; Oudrhiri, Noufissa; Féraud, Olivier; Bacci, Josette; Gobbo, Emilie; Proust, Stéphanie; Turhan, Ali G.

2014-01-01

142

Primary neuroendocrine (Merkel cell) carcinoma of the skin: Morphologic diversity and implications thereof  

Microsoft Academic Search

A significant proportion of primary neuroendocrine cell carcinomas of the skin (Merkel cell carcinomas [MCCs]) have been reported to occur in intimate association with malignant epithelial neoplasms, mainly squamous cell carcinomas. In addition, divergent differentiation within these tumors, particularly of squamous and eccrine types, is not infrequent. This expanded morphologic spectrum of MCC calls for evaluation of potential biologic implications

Noreen M. G Walsh

2001-01-01

143

Morphology, Growth, and Size Limit of Bacterial Cells Hongyuan Jiang1  

E-print Network

Morphology, Growth, and Size Limit of Bacterial Cells Hongyuan Jiang1 and Sean X. Sun1,2 1 a general mechanochemical model of the growing bacterial cell wall, which shows explicitly how growth and shape are coupled together to determine the growth velocity and the bacteria size. The bacterial cell

Sun, Sean

144

The Morphology and Topographic Distribution of AII Amacrine Cells in the Cat Retina  

Microsoft Academic Search

When cat retina is incubated in vitro with the fluorescent dye, 4',6-diamidino-2-phenyl-indole (DAPI), a uniform population of neurons is brightly labelled at the inner border of the inner nuclear layer. The dendritic morphology of the DAPI-labelled cells was defined by iontophoretic injection of Lucifer yellow under direct microscopic control: all the filled cells had the narrow-field bistratified morphology that is

D. I. Vaney

1985-01-01

145

Morphology of human embryonic kidney cells in culture after space flight  

NASA Technical Reports Server (NTRS)

The ability of human embyronic kidney cells to differentiate into small epithelioid, large epithelioid, domed, and fenestrated morphological cell types following space flight is examined. Kidney cells exposed to 1 day at 1 g, then 1 day in orbit, and a 12 minute passage through the electrophoretic separator are compared with control cultures. The data reveal that 70 percent of small epithelioid, 16 percent of large epithelioid, 9 percent of dome-forming, and 5 percent of fenestrated cells formed in the space exposed cells; the distributions correlate well with control data. The formation of domed cells from cells cultured from low electrophoretic mobility fractions and small epithelioid cells from high mobility fractions is unaffected by space flight conditions. It is concluded that storage under microgravity conditions does not influence the morphological differentiation of human embryonic kidney cells in low-passage culture.

Todd, P.; Kunze, M. E.; Williams, K.; Morrison, D. R.; Lewis, M. L.; Barlow, G. H.

1985-01-01

146

A mathematical morphology approach to cell shape analysis  

E-print Network

(E, T ) the power set T E , i.e., the set of functions from E onto T . Typically for the digital 2-D images hal) of size n = -30 to 30. A granulometry is a size distribution based on a pyramid of morphological operators

Paris-Sud XI, Université de

147

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

PubMed

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

Menger, N; Wässle, H

2000-01-01

148

Endothelial Cell Morphology and Migration are Altered by Changes in Gravitational Fields  

NASA Technical Reports Server (NTRS)

Many of the physiological changes of the cardiovascular system during space flight may originate from the dysfunction of basic biological mechanisms caused by microgravity. The weightlessness affects the system when blood and other fluids move to the upper body causing the heart to enlarge to handle the increased blood flow to the upper extremities and decrease circulating volume. Increase arterial pressure triggers baroreceptors which signal the brain to adjust heart rate. Hemodynarnic studies indicate that the microgravity-induced headward fluid redistribution results in various cardiovascular changes such as; alteration of vascular permeability resulting in lipid accumulation in the lumen of the vasculature and degeneration of the the vascular wall, capillary alteration with extensive endothelial invagination. Achieving a true microgravity environment in ground based studies for prolonged periods is virtually impossible. The application of vector-averaged gravity to mammalian cells using horizontal clinostat produces alterations of cellular behavior similar to those observed in microgravity. Similarly, the low shear, horizontally rotating bioreactor (originally designed by NASA) also duplicates several properties of microgravity. Additionally, increasing gravity, i.e., hypcrgravity is easily achieved. Hypergravity has been found to increase the proliferation of several different cell lines (e.g., chick embryo fibroblasts) while decreasing cell motility and slowing liver regeneration following partial hepatectomy. The effect of altered gravity on cells maybe similar to those of other physical forces, i.e. shear stress. Previous studies examining laminar flow and shear stress on endothelial cells found that the cells elongate, orient with the direction of flow, and reorganize their F-actin structure, with concomitant increase in cell stiffness. These studies suggest that alterations in the gravity environment will change the behavior of most cells, including vascular cells. However, few studies have been directed at assessing the effect of altered gravitational field on vascular cell fiction and metabolism, Using image analysis we examined how bovine aortic endothelial cells altered their morphological characteristics and their response to a denudation injury when cells were subjected to simulated microgravity and hypergravity.

Melhado, Caroline; Sanford, Gary; Harris-Hooker, Sandra

1997-01-01

149

Hybrid Solar Cells with Prescribed Nanoscale Morphologies Based onHyperbranched Semiconductor Nanocrystals  

SciTech Connect

In recent years, the search to develop large-area solar cells at low cost has led to research on photovoltaic (PV) systems based on nanocomposites containing conjugated polymers. These composite films can be synthesized and processed at lower costs and with greater versatility than the solid state inorganic semiconductors that comprise today's solar cells. However, the best nanocomposite solar cells are based on a complex architecture, consisting of a fine blend of interpenetrating and percolating donor and acceptor materials. Cell performance is strongly dependent on blend morphology, and solution-based fabrication techniques often result in uncontrolled and irreproducible blends, whose composite morphologies are difficult to characterize accurately. Here we incorporate 3-dimensional hyper-branched colloidal semiconductor nanocrystals in solution-processed hybrid organic-inorganic solar cells, yielding reproducible and controlled nanoscale morphology.

Gur, Ilan; Fromer, Neil A.; Chen, Chih-Ping; Kanaras, AntoniosG.; Alivisatos, A. Paul

2006-09-09

150

Hybrid solar cells with prescribed nanoscale morphologies based on hyperbranched semiconductor nanocrystals.  

PubMed

In recent years, the search to develop large-area solar cells at low cost has led to research on photovoltaic (PV) systems based on nanocomposites containing conjugated polymers. These composite films can be synthesized and processed at lower costs and with greater versatility than the solid state inorganic semiconductors that comprise today's solar cells. However, the best nanocomposite solar cells are based on a complex architecture, consisting of a fine blend of interpenetrating and percolating donor and acceptor materials. Cell performance is strongly dependent on blend morphology, and solution-based fabrication techniques often result in uncontrolled and irreproducible blends, whose composite morphologies are difficult to characterize accurately. Here we incorporate three-dimensional hyperbranched colloidal semiconductor nanocrystals in solution-processed hybrid organic-inorganic solar cells, yielding reproducible and controlled nanoscale morphology. PMID:17298008

Gur, Ilan; Fromer, Neil A; Chen, Chih-Ping; Kanaras, Antonios G; Alivisatos, A Paul

2007-02-01

151

The use of optical coherence tomography for morphological study of scaffolds  

NASA Astrophysics Data System (ADS)

Aimed at possible widening of the optical coherence tomography (OCT) field of application, an attempt is made to use OCT in tissue engineering and cell transplantology as a tool for morphological studies of substrate materials by the example of scaffolds. By means of the traditional fibreoptical OCT scheme the images of inner structure of scaffolds are obtained, and simultaneously the spatial distribution of the intralipid flow velocity is reconstructed using the Doppler OCT. It is shown that combined use of traditional OCT and Doppler OCT schemes allows revealing the regions of the scaffold demonstrating optimal effect of shear stress, which is a key factor of cell growth.

Veksler, B. A.; Kuz'min, V. L.; Kobzev, E. D.; Meglinski, I. V.

2012-05-01

152

The use of optical coherence tomography for morphological study of scaffolds  

SciTech Connect

Aimed at possible widening of the optical coherence tomography (OCT) field of application, an attempt is made to use OCT in tissue engineering and cell transplantology as a tool for morphological studies of substrate materials by the example of scaffolds. By means of the traditional fibreoptical OCT scheme the images of inner structure of scaffolds are obtained, and simultaneously the spatial distribution of the intralipid flow velocity is reconstructed using the Doppler OCT. It is shown that combined use of traditional OCT and Doppler OCT schemes allows revealing the regions of the scaffold demonstrating optimal effect of shear stress, which is a key factor of cell growth.

Veksler, B A; Kuz'min, V L; Kobzev, E D; Meglinski, I V

2012-05-31

153

Single-cell morphological data reveals signaling network architecture  

E-print Network

Metastasis, the migration of cancer cells from the primary site of tumorigenesis and the subsequent invasion of secondary tissues, causes the vast majority of cancer deaths. To spread, metastatic cells dramatically rearrange ...

Nir, Oaz

2010-01-01

154

Multiscale Morphology of Organic Semiconductor Thin Films Controls the Adhesion and Viability of Human Neural Cells  

PubMed Central

Abstract We investigate how multiscale morphology of functional thin films affects the in vitro behavior of human neural astrocytoma 1321N1 cells. Pentacene thin film morphology is precisely controlled by means of the film thickness, ? (here expressed in monolayers (ML)). Fluorescence and atomic force microscopy allow us to correlate the shape, adhesion, and proliferation of cells to the morphological properties of pentacene films controlled by saturated roughness, ?, correlation length, ?, and fractal dimension, df. At early incubation times, cell adhesion exhibits a transition from higher to lower values at ? ? 10 ML. This is explained using a model of conformal adhesion of the cell membrane onto the growing pentacene islands. From the model fitting of the data, we show that the cell explores the surface with a deformation of the membrane whose minimum curvature radius is 90 (± 45) nm. The transition in the adhesion at ?10 ML arises from the saturation of ? accompanied by the monotonic increase of ?, which leads to a progressive decrease of the pentacene local radius of curvature and hence to the surface area accessible to the cell. Cell proliferation is also enhanced for ? < 10 ML, and the optimum morphology parameter ranges for cell deployment and growth are ? ? 6 nm, ? > 500 nm, and df > 2.45. The characteristic time of cell proliferation is ? ? 10 ± 2 h. PMID:20550892

Tonazzini, I.; Bystrenova, E.; Chelli, B.; Greco, P.; Stoliar, P.; Calň, A.; Lazar, A.; Borgatti, F.; D'Angelo, P.; Martini, C.; Biscarini, F.

2010-01-01

155

Correlating Titania Morphology and Chemical Composition with Dye-sensitized Solar Cell Performance  

SciTech Connect

We have investigated the use of various morphologies, including nanoparticles, nanowires, and sea-urchins of TiO{sub 2} as the semiconducting material used as components of dye-sensitized solar cells (DSSCs). Analysis of the solar cells under AM 1.5 solar irradiation reveals the superior performance of hydrothermally derived nanoparticles, by comparison with two readily available commercial nanoparticle materials, within the DSSC architecture. The sub-structural morphology of films of these nanostructured materials has been directly characterized using SEM and indirectly probed using dye desorption. Furthermore, the surfaces of these nanomaterials were studied using TEM in order to visualize their structure, prior to their application within DSSCs. Surface areas of the materials have been quantitatively analyzed by collecting BET adsorption and dye desorption data. Additional investigation using open circuit voltage decay measurements reveals the efficiency of electron conduction through each TiO{sub 2} material. Moreover, the utilization of various chemically distinctive titanate materials within the DSSCs has also been investigated, demonstrating the deficiencies of using these particular chemical compositions within traditional DSSCs.

Santulli, A.C.; Wong, S.; Koenigsmann, C.; Tiano, A.L., DeRosa, D.

2011-04-20

156

Differential Effects of Tissue Culture Coating Substrates on Prostate Cancer Cell Adherence, Morphology and Behavior  

PubMed Central

Weak cell-surface adhesion of cell lines to tissue culture surfaces is a common problem and presents technical limitations to the design of experiments. To overcome this problem, various surface coating protocols have been developed. However, a comparative and precise real-time measurement of their impact on cell behavior has not been conducted. The prostate cancer cell line LNCaP, derived from a patient lymph node metastasis, is a commonly used model system in prostate cancer research. However, the cells’ characteristically weak attachment to the surface of tissue culture vessels and cover slips has impeded their manipulation and analysis and use in high throughput screening. To improve the adherence of LNCaP cells to the culture surface, we compared different coating reagents (poly-l-lysine, poly-l-ornithine, collagen type IV, fibronectin, and laminin) and culturing conditions and analyzed their impact on cell proliferation, adhesion, morphology, mobility and gene expression using real-time technologies. The results showed that fibronectin, poly-l-lysine and poly-l-ornithine improved LNCaP cells adherence and provoked cell morphology alterations, such as increase of nuclear and cellular area. These coating reagents also induced a higher expression of F-actin and reduced cell mobility. In contrast, laminin and collagen type IV did not improve adherence but promoted cell aggregation and affected cell morphology. Cells cultured in the presence of laminin displayed higher mobility than control cells. All the coating conditions significantly affected cell viability; however, they did not affect the expression of androgen receptor-regulated genes. Our comparative findings provide important insight for the selection of the ideal coating reagent and culture conditions for the cancer cell lines with respect to their effect on proliferation rate, attachment, morphology, migration, transcriptional response and cellular cytoskeleton arrangement. PMID:25375165

Liberio, Michelle S.; Sadowski, Martin C.; Soekmadji, Carolina; Davis, Rohan A.; Nelson, Colleen C.

2014-01-01

157

Trimidox-mediated morphological changes during erythroid differentiation is associated with the stimulation of hemoglobin and F-cell production in human K562 cells.  

PubMed

Trimidox (3,4,5-trihdroxybenzamidoxime) has been shown to reduce the activity of ribonucleotide reductase with accompanied growth inhibition and differentiation of mammalian cells. Hydroxyurea (HU) is the only ribonucleotide reductase inhibitor in clinical use for the treatment and management of sickle cell anemia, since this compound increases fetal hemoglobin (Hb F) production: a potent inhibitor of sickle hemoglobin (Hb SS) polymerization. However, the main limitations of HU is its lack of potency, myelosuppression and short half life. These studies investigated the effects of trimidox on the induction of hemoglobin and F-cells production in K562 erythroleukemia cells. Our study reveals that trimidox exhibits concentration dependent inhibitory effect on K562 cells with increase in benzidine positive normoblasts and F-cells production as well as morphological changes typical of erythroid differentiation. These findings provide the first evidence that the growth inhibitory differentiation of cells induced by trimidox enhance hemoglobin and F-cells production. PMID:9647767

Iyamu, E W; Adunyah, S E; Elford, H L; Fasold, H; Turner, E A

1998-06-29

158

Metabolic diversion of the phenylpropanoid pathway causes cell wall and morphological changes in transgenic tobacco stems.  

PubMed

Studies involving transgenic plants with modifications in the lignin pathway reported to date, have received a relatively preliminary characterisation in relation to the impact on vascular integrity, biomechanical properties of tissues and carbon allocation to phenolic pools. Therefore, in this study transgenic tobacco plants (Nicotiana tabacum cv XHFD 8) expressing various levels of a bacterial 4-hydroxycinnamoyl-CoA hydratase/lyase (HCHL) gene have been characterised for cell wall and related morphological changes. The HCHL enzyme converts p-coumaroyl-CoA to 4-hydroxybenzaldehyde thereby rerouting the phenylpropanoid pathway. Plants expressing high levels of HCHL activity exhibited reduced lignin deposition, impaired monolignol biosynthesis and vascular integrity. The plants also exhibited reduction in stem toughness concomitant with a massive reduction in both the cell wall esterified and soluble phenolics. A notable result of redirecting the carbon flux was the wall-bound accretion of vanillin and vanillic acid, probably due to the shunt pathway. Intracellular accumulation of novel metabolites such as hydroxybenzoic and vanillic acid derivatives also occurred in the transgenic plants. A line with intermediate levels of HCHL expression conferred correspondingly reduced lignin deposition, toughness and phenolics. This line displayed a normal morphology but distorted vasculature. Coloration of the xylem has been previously attributed to incorporation of alternative phenolics, whereas results from this study indicate that the coloration is likely to be due to the association of low molecular weight phenolics. There was no evidence of increased growth or enhanced cellulose biosynthesis as a result of HCHL expression. Hence, rerouting the phenylpropanoid biosynthetic pathway quantitatively and qualitatively modifies cell wall-bound phenolics and vascular structure. PMID:17120022

Merali, Zara; Mayer, Melinda J; Parker, Mary L; Michael, Anthony J; Smith, Andrew C; Waldron, Keith W

2007-04-01

159

Morphological restriction of human coronary artery endothelial cells substantially impacts global gene expression patterns  

PubMed Central

Alterations in cell shape have been shown to modulate chromatin condensation and cell lineage specification; however, the mechanisms controlling these processes are largely unknown. Because endothelial cells experience cyclic mechanical changes from blood flow during normal physiological processes and disrupted mechanical changes as a result of abnormal blood flow, cell shape deformation and loss of polarization during coronary artery disease, we aimed to determine how morphological restriction affects global gene expression patterns. Human coronary artery endothelial cells (HCAECs) were cultured on spatially defined adhesive micropatterns, forcing them to conform to unique cellular morphologies differing in cellular polarization and angularity. We utilized pattern recognition algorithms and statistical analysis to validate the cytoskeletal pattern reproducibility and uniqueness of each micropattern, and performed microarray analysis on normal-shaped and micropatterned HCAECs to determine how constrained cellular morphology affects gene expression patterns. Analysis of the data revealed that forcing HCAECs to conform to geometrically-defined shapes significantly affects their global transcription patterns compared to nonrestricted shapes. Interestingly, gene expression patterns were altered in response to morphological restriction in general, although they were consistent regardless of the particular shape the cells conformed to. These data suggest that the ability of HCAECs to spread, although not necessarily their particular morphology, dictates their genomics patterns. PMID:23802622

Stiles, Jessica M; Pham, Robert; Rowntree, Rebecca K; Amaya, Clarissa; Battiste, James; Boucheron, Laura E; Mitchell, Dianne C; Bryan, Brad A

2013-01-01

160

Morphological Measurement of Living Cells in Methanol with Digital Holographic Microscopy  

PubMed Central

Cell morphology is the research foundation in many applications related to the estimation of cell status, drug response, and toxicity screening. In biomedical field, the quantitative phase detection is an inevitable trend for living cells. In this paper, the morphological change of HeLa cells treated with methanol of different concentrations is detected using digital holographic microscopy. The compact image-plane digital holographic system is designed based on fiber elements. The quantitative phase image of living cells is obtained in combination with numerical analysis. The statistical analysis shows that the area and average optical thickness of HeLa cells treated with 12.5% or 25% methanol reduce significantly, which indicates that the methanol with lower concentration could cause cellular shrinkage. The area of HeLa cells treated with 50% methanol is similar to that of normal cells (P > 0.05), which reveals the fixative effect of methanol with higher concentration. The maximum optical thickness of the cells treated with 12.5%, 25%, and 50% methanol is greater than that of untreated cells, which implies the pyknosis of HeLa cells under the effect of methanol. All of the results demonstrate that digital holographic microscopy has supplied a noninvasive imaging alternative to measure the morphological change of label-free living cells. PMID:23424605

Wang, Yunxin; Yang, Yishu; Wang, Dayong; Ouyang, Liting; Zhang, Yizhuo; Zhao, Jie; Wang, Xinlong

2013-01-01

161

Morphological measurement of living cells in methanol with digital holographic microscopy.  

PubMed

Cell morphology is the research foundation in many applications related to the estimation of cell status, drug response, and toxicity screening. In biomedical field, the quantitative phase detection is an inevitable trend for living cells. In this paper, the morphological change of HeLa cells treated with methanol of different concentrations is detected using digital holographic microscopy. The compact image-plane digital holographic system is designed based on fiber elements. The quantitative phase image of living cells is obtained in combination with numerical analysis. The statistical analysis shows that the area and average optical thickness of HeLa cells treated with 12.5% or 25% methanol reduce significantly, which indicates that the methanol with lower concentration could cause cellular shrinkage. The area of HeLa cells treated with 50% methanol is similar to that of normal cells (P > 0.05), which reveals the fixative effect of methanol with higher concentration. The maximum optical thickness of the cells treated with 12.5%, 25%, and 50% methanol is greater than that of untreated cells, which implies the pyknosis of HeLa cells under the effect of methanol. All of the results demonstrate that digital holographic microscopy has supplied a noninvasive imaging alternative to measure the morphological change of label-free living cells. PMID:23424605

Wang, Yunxin; Yang, Yishu; Wang, Dayong; Ouyang, Liting; Zhang, Yizhuo; Zhao, Jie; Wang, Xinlong

2013-01-01

162

Bioeffective Ultrasound at Very Low Doses: Reversible Manipulation of Neuronal Cell Morphology and Function in Vitro  

NASA Astrophysics Data System (ADS)

Direct and safe manipulation of neurons by external means is an increasingly studied therapeutic modality with the potential to treat many neurological diseases. Anticipating such future applications, we investigated reversible bioeffects of very low dose focused ultrasound on neuronal cell morphology and function in vitro. To test morphological changes, undifferentiated PC12 cells were serum-cultured. The culture plates were placed on an inverted optical microscope. An f/1.1 ultrasound transducer with a water-filled coupling cone was focused on the culture and excited with 30-ms 4.67-MHz 100-kPa pulses. To test functional changes, rat hippocampal slices were cultured and individually transferred to the well of a 60-channel multi electrode array. An f/2.1 ultrasound transducer with a water-filled coupling cone was focused on a culture and excited with 100-?s 4.04-MHz 77-kPa pulses. The culture was stimulated before and after the ultrasonic stimulus with a 100-?s 100-?A biphasic electrical stimulus. Optical microscopy of PC12 cultures under insonification revealed that cells that were clustered near the ultrasound focal region elongated by approximately 2 ?m during insonification and returned to approximately their original shapes following insonification. We conclude that the acoustic radiation force is capable of reversibly deforming cultured cells. In the rat hippocampal cultures, the ultrasonically and electrically evoked responses exhibited similar biphasic waveforms. In addition, robust electrically evoked responses following insonification indicated that the insonified cultures remained viable. We conclude that low-dose ultrasound can stimulate neurons; the mechanism is currently under investigation.

Muratore, Robert; LaManna, Justine; Szulman, Erin; Kalisz, M. S. Andrew; Lamprecht, Michael; Simon, M. S. Melissa; Yu, M. S. Zhe; Xu, Nina; Morrison, Barclay

2009-04-01

163

Light-induced morphological alteration in anthocyanin-accumulating vacuoles of maize cells  

PubMed Central

Background Plant pigmentation is affected by a variety of factors. Light, an important plant developmental signal, influences the accumulation of anthocyanins primarily through the activation of the transcription factors that regulate the flavonoid biosynthetic pathway. In this study, we utilized maize Black Mexican Sweet (BMS) cells expressing the R and C1 regulators of anthocyanin biosynthesis from a light-insensitive promoter as a means to investigate the existence of additional levels of control of pigmentation by light. Results BMS cells expressing the R and C1 regulators from the CaMV 35S constitutive promoter accumulate anthocyanins when grown in complete darkness, suggesting that the transcription factors R and C1 are sufficient for the transcription of the genes corresponding to the structural enzymes of the pathway, with no requirement for additional light-induced regulators. Interestingly, light induces a "darkening" in the color of the purple anthocyanin pigmentation of transgenic BMS cells expressing R and C1. This change in the pigment hue is not associated with a variation in the levels or types of anthocyanins present, or with an alteration of the transcript levels of several flavonoid biosynthetic genes. However, cytological observations show that light drives unexpected changes in the morphology and distribution of the anthocyanins-containing vacuolar compartments. Conclusion By uncoupling the effect of light on anthocyanin accumulation, we have found light to induce the fusion of anthocyanin-containing vacuoles, the coalescence of anthocyanic vacuolar inclusion (AVI)-like structures contained, and the spread of anthocyanins from the inclusions into the vacuolar sap. Similar light-induced alterations in vacuolar morphology are also evident in the epidermal cells of maize floral whorls accumulating anthocyanins. Our findings suggest a novel mechanism for the action of light on the vacuolar storage of anthocyanin. PMID:15907203

Irani, Niloufer G; Grotewold, Erich

2005-01-01

164

A mitochondrial protein affects cell morphology, mitochondrial segregation and virulence in Leishmania q  

E-print Network

#12;A mitochondrial protein affects cell morphology, mitochondrial segregation and virulence with the nucleus and plays a crucial role in cell division. However, despite its importance and potential as a drug partly understood. In our quest to identify novel mitochondrial proteins in Leishmania, we constructed

McFadden, Geoff

165

Morphological and functional changes of mitochondria in apoptotic esophageal carcinoma cells induced by arsenic trioxide  

Microsoft Academic Search

AIM: To demonstrate that mitochondrial morphological and functional changes are an important intermediate link in the course of apoptosis in esophageal carcinoma cells induced by As2O3. METHODS: The esophageal carcinoma cell line SHEEC1, established in our laboratory, was cultured in 199 growth medium, supplemented with 100mL·L -1 calf

Zhong-Ying Shen; Jian Shen; Qiao-Shan Li; Cai-Yun Chen; Jiong-Yu Chen; Yi Zeng

2002-01-01

166

Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells.  

PubMed

A series of Sr-substituted hydroxyapatites (HA), of general formula Ca(10-x)Srx(PO4)6(OH)2, where x=2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl2, in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in HA has a positive effect on MG-63 cells. In contrast, Sr ions alone, at the concentrations released by Sr-HA (1.21-3.24 ppm), influenced neither cell proliferation nor differentiation. Thus the positive effects of Sr in Sr-HA materials are probably due to the co-action of other ions such as Ca and P. PMID:23827552

Aina, Valentina; Bergandi, Loredana; Lusvardi, Gigliola; Malavasi, Gianluca; Imrie, Flora E; Gibson, Iain R; Cerrato, Giuseppina; Ghigo, Dario

2013-04-01

167

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?cells by coculture with PASCs; thus these cells can be used for transplantation, providing a theoretical foundation for the treatment of diabetes using this approach. PMID:25262665

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

2015-03-01

168

Altered Mitochondria Morphology and Cell Metabolism in Apaf1-Deficient Cells  

PubMed Central

Background Apaf1 (apoptotic protease activating factor 1) is the central component of the apoptosome, a multiprotein complex that activates procaspase-9 after cytochrome c release from the mitochondria in the intrinsic pathway of apoptosis. Other cellular roles, including a pro-survival role, have also been described for Apaf1, while the relative contribution of each function to cell death, but also to cell homeostatic conditions, remain to be clarified. Methodology and Principal Findings Here we examined the response to apoptosis induction of available embryonic fibroblasts from Apaf1 knockout mice (MEFS KO Apaf1). In the absence of Apaf1, cells showed mitochondria with an altered morphology that affects cytochrome c release and basal metabolic status. Conclusions We analysed mitochondrial features and cell death response to etoposide and ABT-737 in two different Apaf1-deficient MEFS, which differ in the immortalisation protocol. Unexpectedly, MEFS KO Apaf1 immortalised with the SV40 antigen (SV40IM-MEFS Apaf1) and those which spontaneously immortalised (SIM-MEFS Apaf1) respond differently to apoptotic stimuli, but both presented relevant differences at the mitochondria when compared to MEFS WT, indicating a role for Apaf1 at the mitochondria. PMID:24416260

Herrera, Andrés E.; Andreu-Fernández, Vicente; Ferraro, Elisabetta; Cecconi, Francesco; Orzáez, Mar; Pérez-Payá, Enrique

2014-01-01

169

Relating morphological characteristics to the open-circuit voltage of organic bulk-heterojunction solar cells  

NASA Astrophysics Data System (ADS)

A closed-form expression for the open-circuit voltage of organic bulk-heterojunction solar cells is derived as a function of the donor/acceptor morphology based on a spatially smoothed modelling framework. It is found that the open-circuit voltage of organic solar cells is in leading order determined by a single morphological feature: the ratio between the donor volume fraction and the specific interfacial area. Other morphological characteristics of the donor/acceptor blend, such as the connectivity of percolation pathways, do not have significant impact on the open-circuit voltage. Our findings are verified with detailed charge carrier transport simulations utilizing randomly generated donor/acceptor morphologies.

Zhang, Teng; Birgersson, Erik; Luther, Joachim

2015-02-01

170

Morphological and cytochemical determination of cell death by apoptosis  

Microsoft Academic Search

Several modes of cell death are now recognized, including necrosis, apoptosis, and autophagy. Oftentimes the distinctions\\u000a between these various modes may not be apparent, although the precise mode may be physiologically important. Accordingly,\\u000a it is often desirable to be able to classify the mode of cell death. Apoptosis was originally defined by structural alterations\\u000a in cells observable by transmitted light

Douglas J. Taatjes; Burton E. Sobel; Ralph C. Budd

2008-01-01

171

Differences in regulation of tight junctions and cell morphology between VHL mutations from disease subtypes  

PubMed Central

Background In von Hippel-Lindau (VHL) disease, germline mutations in the VHL tumor suppressor gene cause clear cell renal carcinomas, hemangioblastomas, and pheochromocytomas. The VHL gene product is part of an ubiquitin E3 ligase complex and hypoxia-inducible factor alpha (HIF-?) is a key substrate, although additional VHL functions have been described. A genotype-phenotype relationship exists in VHL disease such that specific VHL mutations elicit certain subsets of these tumors. Here, we examine VHL genotype-phenotype correlations at the cellular level, focusing on the regulation of tight junctions and cell morphology. Methods Wild-type and various mutant VHL proteins representing VHL disease subtypes were stably expressed in 3 VHL-negative renal carcinoma cell lines. Using these cell lines, the roles of various VHL-associated cellular functions in regulation of cell morphology were investigated. Results As a whole, type 1 mutants varied greatly from type 2 mutants, demonstrating high levels of HIF-2?, cyclin D1 and ?5 integrin, lower p27 levels, and a spindly, fibroblastic cellular appearance. Type 2 mutations demonstrated an epithelial morphology similar to wild-type VHL in the majority of the renal cell lines used. Knockdown of p27 in cells with wild-type VHL led to perturbations of both epithelial morphology and ZO-1 localization to tight junctions. ZO-1 localization correlated well with VHL disease subtypes, with greater mislocalization observed for genotypes associated with a higher risk of renal carcinoma. HIF-2? knockdown in 786-O partially restored ZO-1 localization, but did not restore an epithelial morphology. Conclusion VHL has both HIF-? dependent and HIF-? independent functions in regulating tight junctions and cell morphology that likely impact the clinical phenotypes seen in VHL disease. PMID:19602254

2009-01-01

172

Morphological and cytochemical determination of cell death by apoptosis  

PubMed Central

Several modes of cell death are now recognized, including necrosis, apoptosis, and autophagy. Oftentimes the distinctions between these various modes may not be apparent, although the precise mode may be physiologically important. Accordingly, it is often desirable to be able to classify the mode of cell death. Apoptosis was originally defined by structural alterations in cells observable by transmitted light and electron microscopy. Today, a wide variety of imaging and cytochemical techniques are available for the investigation of apoptosis. This review will highlight many of these methods, and provide a critique on the advantages and disadvantages associated with them for the specific identification of apoptotic cells in culture and tissues. PMID:18000678

Sobel, Burton E.; Budd, Ralph C.

2007-01-01

173

Morphologic categorization of cell death induced by mild hyperthermia and comparison with death induced by ionizing radiation and cytotoxic drugs  

SciTech Connect

This paper presents a summary of the morphological categorization of cell death, results of two in vivo studies on the cell death induced by mild hyperthermia in rat small intestine and mouse mastocytoma, and a comparison of the cell death induced by hyperthermia, radiation and cytotoxic drugs. Two distinct forms of cell death, apoptosis and necrosis, can be recognized on morphologic grounds. Apoptosis appears to be a process of active cellular self-destruction to which a biologically meaningful role can usually be attributed, whereas necrosis is a passive degenerative phenomenon that results from irreversible cellular injury. Light and transmission electron microscopic studies showed that lower body hyperthermia (43 degrees C for 30 min) induced only apoptosis of intestinal epithelial cells, and of lymphocytes, plasma cells, and eosinophils. In the mastocytoma, hyperthermia (43 degrees C for 15 min) produced widespread tumor necrosis and also enhanced apoptosis of tumor cells. Ionizing radiation and cytotoxic drugs are also known to induce apoptosis in a variety of tissues. It is attractive to speculate that DNA damage by each agent is the common event which triggers the same process of active cellular self-destruction that characteristically effects selective cell deletion in normal tissue homeostasis.

Allan, D.J.; Harmon, B.V.

1986-01-01

174

Role of Cortical Cell Type and Morphology in Sub- and Suprathreshold Uniform Electric Field Stimulation  

PubMed Central

Background The neocortex is the most common target of sub-dural electrotherapy and non-invasive brain stimulation modalities including transcranial magnetic stimulation (TMS) and transcranial current simulation (TCS). Specific neuronal elements targeted by cortical stimulation are considered to underlie therapeutic effects, but the exact cell-type(s) affected by these methods remains poorly understood. Objective We determined if neuronal morphology or cell type predicted responses to sub- and suprathreshold uniform electric fields. Methods We characterized the effects of sub- and supra-threshold electrical stimulation on identified cortical neurons in vitro. Uniform electric fields were applied to rat motor cortex brain slices, while recording from interneurons and pyramidal cells across cortical layers, using whole cell patch clamp. Neuron morphology was reconstructed following intracellular dialysis of biocytin. Based solely on volume-weighted morphology, we developed a parsimonious model of neuronal soma polarization by sub-threshold electric fields. Results We found that neuronal morphology correlated with somatic sub-threshold polarization. Based on neuronal morphology, we predict layer V pyramidal neuronal soma to be the most sensitive to polarization by optimally oriented sub-threshold fields. Supra-threshold electric field action potential threshold was shown to reflect both direct cell polarization and synaptic (network) activation. Layer V/VI neuron absolute electric field action potential thresholds were lower than Layer II/III pyramidal neurons and interneurons. Compared to somatic current injection, electric fields promoted burst firing and modulated action potential firing times. PMID:20161507

Radman, Thomas; Ramos, Raddy L; Brumberg, Joshua C; Bikson, Marom

2009-01-01

175

Analysis of effect of nanoporous alumina substrate coated with polypyrrole nanowire on cell morphology based on AFM topography.  

PubMed

In this study, in situ electrochemical synthesis of polypyrrole nanowires with nanoporous alumina template was described. The formation of highly ordered porous alumina substrate was demonstrated with Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). In addition, Fourier transform infrared analysis confirmed that polypyrrole (PP) nanowires were synthesized by direct electrochemical oxidation of pyrrole. HeLa cancer cells and HMCF normal cells were immobilized on the polypyrrole nanowires/nanoporous alumina substrates to determine the effects of the substrate on the cell morphology, adhesion and proliferation as well as the biocompatibility of the substrate. Cell adhesion and proliferation were characterized using a standard MTT assay. The effects of the polypyrrole nanowires/nanoporous alumina substrate on the cell morphology were studied by AFM. The nanoporous alumina coated with polypyrrole nanowires was found to exhibit better cell adhesion and proliferation than polystyrene petridish, aluminum foil, 1st anodized and uncoated 2nd anodized alumina substrate. This study showed the potential of the polypyrrole nanowires/nanoporous alumina substrate as biocompatibility electroactive polymer substrate for both healthy and cancer cell cultures applications. PMID:20207084

El-Said, Waleed Ahmed; Yea, Cheol-Heon; Jung, Mi; Kim, Hyuncheol; Choi, Jeong-Woo

2010-05-01

176

The Observation Report of Red Blood Cell Morphology in Thailand Teenager by Using Data Mining Technique  

PubMed Central

It is undeniable that laboratory information is important in healthcare in many ways such as management, planning, and quality improvement. Laboratory diagnosis and laboratory results from each patient are organized from every treatment. These data are useful for retrospective study exploring a relationship between laboratory results and diseases. By doing so, it increases efficiency in diagnosis and quality in laboratory report. Our study will utilize J48 algorithm, a data mining technique to predict abnormality in peripheral blood smear from 1,362 students by using 13 data set of hematological parameters gathered from automated blood cell counter. We found that the decision tree which is created from the algorithm can be used as a practical guideline for RBC morphology prediction by using 4 hematological parameters (MCV, MCH, Hct, and RBC). The average prediction of RBC morphology has true positive, false positive, precision, recall, and accuracy of 0.940, 0.050, 0.945, 0.940, and 0.943, respectively. A newly found paradigm in managing medical laboratory information will be helpful in organizing, researching, and assisting correlation in multiple disciplinary other than medical science which will eventually lead to an improvement in quality of test results and more accurate diagnosis. PMID:24683415

Saichanma, Sarawut; Chulsomlee, Sucha; Thangrua, Nonthaya; Pongsuchart, Pornsuri; Sanmun, Duangmanee

2014-01-01

177

Fibrocartilage tissue engineering: the role of the stress environment on cell morphology and matrix expression.  

PubMed

Although much is known about the effects of uniaxial mechanical loading on fibrocartilage development, the stress fields to which fibrocartilaginous regions are subjected to during development are mutiaxial. That fibrocartilage develops at tendon-to-bone attachments and in compressive regions of tendons is well established. However, the three-dimensional (3D) nature of the stresses needed for the development of fibrocartilage is not known. Here, we developed and applied an in vitro system to determine whether fibrocartilage can develop under a state of periodic hydrostatic tension in which only a single principal component of stress is compressive. This question is vital to efforts to mechanically guide morphogenesis and matrix expression in engineered tissue replacements. Mesenchymal stromal cells in a 3D culture were exposed to compressive and tensile stresses as a result of an external tensile hydrostatic stress field. The stress field was characterized through mechanical modeling. Tensile cyclic stresses promoted spindle-shaped cells, upregulation of scleraxis and type one collagen, and cell alignment with the direction of tension. Cells experiencing a single compressive stress component exhibited rounded cell morphology and random cell orientation. No difference in mRNA expression of the genes Sox9 and aggrecan was observed when comparing tensile and compressive regions unless the medium was supplemented with the chondrogenic factor transforming growth factor beta3. In that case, Sox9 was upregulated under static loading conditions and aggrecan was upregulated under cyclic loading conditions. In conclusion, the fibrous component of fibrocartilage could be generated using only mechanical cues, but generation of the cartilaginous component of fibrocartilage required biologic factors in addition to mechanical cues. These studies support the hypothesis that the 3D stress environment influences cell activity and gene expression in fibrocartilage development. PMID:21091338

Thomopoulos, Stavros; Das, Rosalina; Birman, Victor; Smith, Lester; Ku, Katherine; Elson, Elliott L; Pryse, Kenneth M; Marquez, Juan Pablo; Genin, Guy M

2011-04-01

178

Fibrocartilage Tissue Engineering: The Role of the Stress Environment on Cell Morphology and Matrix Expression  

PubMed Central

Although much is known about the effects of uniaxial mechanical loading on fibrocartilage development, the stress fields to which fibrocartilaginous regions are subjected to during development are mutiaxial. That fibrocartilage develops at tendon-to-bone attachments and in compressive regions of tendons is well established. However, the three-dimensional (3D) nature of the stresses needed for the development of fibrocartilage is not known. Here, we developed and applied an in vitro system to determine whether fibrocartilage can develop under a state of periodic hydrostatic tension in which only a single principal component of stress is compressive. This question is vital to efforts to mechanically guide morphogenesis and matrix expression in engineered tissue replacements. Mesenchymal stromal cells in a 3D culture were exposed to compressive and tensile stresses as a result of an external tensile hydrostatic stress field. The stress field was characterized through mechanical modeling. Tensile cyclic stresses promoted spindle-shaped cells, upregulation of scleraxis and type one collagen, and cell alignment with the direction of tension. Cells experiencing a single compressive stress component exhibited rounded cell morphology and random cell orientation. No difference in mRNA expression of the genes Sox9 and aggrecan was observed when comparing tensile and compressive regions unless the medium was supplemented with the chondrogenic factor transforming growth factor beta3. In that case, Sox9 was upregulated under static loading conditions and aggrecan was upregulated under cyclic loading conditions. In conclusion, the fibrous component of fibrocartilage could be generated using only mechanical cues, but generation of the cartilaginous component of fibrocartilage required biologic factors in addition to mechanical cues. These studies support the hypothesis that the 3D stress environment influences cell activity and gene expression in fibrocartilage development. PMID:21091338

Das, Rosalina; Birman, Victor; Smith, Lester; Ku, Katherine; Elson, Elliott L.; Pryse, Kenneth M.; Marquez, Juan Pablo; Genin, Guy M.

2011-01-01

179

Methyl Jasmonate Affects Morphology, Number and Activity of Endoplasmic Reticulum Bodies in Raphanus sativus Root Cells.  

PubMed

The endoplasmic reticulum (ER) bodies are ER-derived structures that are found in Brassicaceae species and thought to play a role in defense. Here, we have investigated the occurrence, distribution and function of ER bodies in root cells of Raphanus sativus using a combination of microscopic and biochemical methods. We have also assessed the response of ER bodies to methyl jasmonate (MeJA), a phytohormone that mediates plant defense against wounding and pathogens. Our results show that (i) ER bodies do occur in different root cell types from the root cap region to the differentiation zone; (ii) they do accumulate a PYK10-like protein similar to the major marker protein of ER bodies that is involved in defense in Arabidopsis thaliana; and (iii) treatment of root cells with MeJA causes a significant increase in the number of ER bodies and the activity of ?-glucosidases. More importantly, MeJA was found to induce the formation of very long ER bodies that results from the fusion of small ones, a phenomenon that has not been reported in any other study so far. These findings demonstrate that MeJA impacts the number and morphology of functional ER bodies and stimulates ER body enzyme activities, probably to participate in defense responses of radish root. They also suggest that these structures may provide a defensive system specific to root cells. PMID:25305245

Gotté, Maxime; Ghosh, Rajgourab; Bernard, Sophie; Nguema-Ona, Eric; Vicré-Gibouin, Maďté; Hara-Nishimura, Ikuko; Driouich, Azeddine

2015-01-01

180

Nuclear magnetic resonance studies of macroscopic morphology and dynamics  

SciTech Connect

Nuclear magnetic resonance techniques are traditionally used to study molecular level structure and dynamics with a noted exception in medically applied NMR imaging (MRI). In this work, new experimental methods and theory are presented relevant to the study of macroscopic morphology and dynamics using NMR field gradient techniques and solid state two-dimensional exchange NMR. The goal in this work is not to take some particular system and study it in great detail, rather it is to show the utility of a number of new and novel techniques using ideal systems primarily as a proof of principle. By taking advantage of the analogy between NMR imaging and diffraction, one may simplify the experiments necessary for characterizing the statistical properties of the sample morphology. For a sample composed of many small features, e.g. a porous medium, the NMR diffraction techniques take advantage of both the narrow spatial range and spatial isotropy of the sample`s density autocorrelation function to obtain high resolution structural information in considerably less time than that required by conventional NMR imaging approaches. The time savings of the technique indicates that NMR diffraction is capable of finer spatial resolution than conventional NMR imaging techniques. Radio frequency NMR imaging with a coaxial resonator represents the first use of cylindrically symmetric field gradients in imaging. The apparatus as built has achieved resolution at the micron level for water samples, and has the potential to be very useful in the imaging of circularly symmetric systems. The study of displacement probability densities in flow through a random porous medium has revealed the presence of features related to the interconnectedness of the void volumes. The pulsed gradient techniques used have proven successful at measuring flow properties for time and length scales considerably shorter than those studied by more conventional techniques.

Barrall, G.A. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley Lab., CA (United States). Materials Science Div.

1995-09-01

181

Investigation of cell morphology for disease diagnostics via high content screening  

NASA Astrophysics Data System (ADS)

Ninety percent of all cancer-related deaths are caused by metastatic disease, i.e. the spreading of a subset of cells from a primary tumor in an organ to distal sites in other organs. Understanding this progression from localized to metastatic disease is essential for further developing effective therapeutic and treatment strategies. However, despite research efforts, no distinct genetic, epigenetic, or proteomic signature of cancer metastasis has been identified so far. Metastasis is a physical event: through invasion and migration through the dense, tortuous stromal matrix, intravasation, shear forces of blood flow, successful re-attachment to blood vessel walls, migration, the colonization of a distal site, and, finally, reactivation following dormancy, metastatic cells may share precise physical properties. Cell morphology is the most direct physical property that can be measured. In this work, we develop a high throughput cell phenotyping process and investigate the morphological signature of primary tumor cells and liver metastatic pancreatic cancer cells.

Khatau, Shyam

2013-03-01

182

Effect of Substrate Morphology Slope Distributions on Light Scattering, nc-Si:H Film Growth, and Solar Cell Performance.  

PubMed

Thin-film silicon solar cells are often deposited on textured ZnO substrates. The solar-cell performance is strongly correlated to the substrate morphology, as this morphology determines light scattering, defective-region formation, and crystalline growth of hydrogenated nanocrystalline silicon (nc-Si:H). Our objective is to gain deeper insight in these correlations using the slope distribution, rms roughness (?rms) and correlation length (lc) of textured substrates. A wide range of surface morphologies was obtained by Ar plasma treatment and wet etching of textured and flat-as-deposited ZnO substrates. The ?rms, lc and slope distribution were deduced from AFM scans. Especially, the slope distribution of substrates was represented in an efficient way that light scattering and film growth direction can be more directly estimated at the same time. We observed that besides a high ?rms, a high slope angle is beneficial to obtain high haze and scattering of light at larger angles, resulting in higher short-circuit current density of nc-Si:H solar cells. However, a high slope angle can also promote the creation of defective regions in nc-Si:H films grown on the substrate. It is also found that the crystalline fraction of nc-Si:H solar cells has a stronger correlation with the slope distributions than with ?rms of substrates. In this study, we successfully correlate all these observations with the solar-cell performance by using the slope distribution of substrates. PMID:25418361

Kim, Do Yun; Santbergen, Rudi; Jäger, Klaus; Sever, Martin; Kr?, Janez; Topi?, Marko; Hänni, Simon; Zhang, Chao; Heidt, Anna; Meier, Matthias; van Swaaij, René A C M M; Zeman, Miro

2014-12-24

183

Promyelocytic leukemia (PML) protein plays important roles in regulating cell adhesion, morphology, proliferation and migration.  

PubMed

PML protein plays important roles in regulating cellular homeostasis. It forms PML nuclear bodies (PML-NBs) that act like nuclear relay stations and participate in many cellular functions. In this study, we have examined the proteome of mouse embryonic fibroblasts (MEFs) derived from normal (PML(+/+)) and PML knockout (PML(-/-)) mice. The aim was to identify proteins that were differentially expressed when MEFs were incapable of producing PML. Using comparative proteomics, total protein were extracted from PML(-/-) and PML(+/+) MEFs, resolved by two dimensional electrophoresis (2-DE) gels and the differentially expressed proteins identified by LC-ESI-MS/MS. Nine proteins (PML, NDRG1, CACYBP, CFL1, RSU1, TRIO, CTRO, ANXA4 and UBE2M) were determined to be down-regulated in PML(-/-) MEFs. In contrast, ten proteins (CIAPIN1, FAM50A, SUMO2 HSPB1 NSFL1C, PCBP2, YWHAG, STMN1, TPD52L2 and PDAP1) were found up-regulated. Many of these differentially expressed proteins play crucial roles in cell adhesion, migration, morphology and cytokinesis. The protein profiles explain why PML(-/-) and PML(+/+) MEFs were morphologically different. In addition, we demonstrated PML(-/-) MEFs were less adhesive, proliferated more extensively and migrated significantly slower than PML(+/+) MEFs. NDRG1, a protein that was down-regulated in PML(-/-) MEFs, was selected for further investigation. We determined that silencing NDRG1expression in PML(+/+) MEFs increased cell proliferation and inhibited PML expression. Since NDRG expression was suppressed in PML(-/-) MEFs, this may explain why these cells proliferate more extensively than PML(+/+) MEFs. Furthermore, silencing NDRG1expression also impaired TGF-?1 signaling by inhibiting SMAD3 phosphorylation. PMID:23555679

Tang, Mei Kuen; Liang, Yong Jia; Chan, John Yeuk Hon; Wong, Sing Wan; Chen, Elve; Yao, Yao; Gan, Jingyi; Xiao, Lihai; Leung, Hin Cheung; Kung, Hsiang Fu; Wang, Hua; Lee, Kenneth Ka Ho

2013-01-01

184

Exocytosis in normal anterior pituitary cells. Quantitative correlation between growth hormone release and the morphological features of exocytosis.  

PubMed Central

We have used high-pressure freezing techniques to study exocytosis in rat anterior pituitary cells. The cells were either unstimulated or exposed to 1 nM growth hormone releasing factor (GRF) for 10 min before ultrarapid freezing. The magnitude of growth hormone (GH) release was then correlated with the number of exocytotic events observed with freeze-fracture electron microscopy. High-pressure freezing of unfixed and uncryoprotected specimens permits cryofixation of samples up to 1 mm diam (0.5 mm thick) without ice crystal damage, and arrests exocytotic events within 10 ms. Our studies comparing conventionally fixed specimens with those prepared by high-pressure freezing confirm that areas of intramembrane particle clearing at potential exocytotic sites are an artifact of conventional fixation and/or cryoprotection techniques. The cells exposed to 1 nM GRF released approximately fivefold more GH than did unstimulated cells. Morphologically, we have observed a 3.3-fold increase in the number of exocytotic events in GRF-stimulated cells, 33.7 events/100 micron2 compared with 10.4 events/100 micron2 for unstimulated cells. In additional experiments, we studied the effects of two inhibitors of GRF-induced exocytosis, somatostatin and sodium isethionate. Both compounds elicit the same response, a parallel decrease in exocytotic events and in secreted product. We conclude that high-pressure freezing, combined with freeze-fracture and freeze-substitution processing techniques, is an excellent tool for studying the morphological aspects of exocytosis. In the present investigation, it has allowed us to quantitatively relate the biochemistry and morphology of exocytosis in anterior pituitary cells. Images PMID:2895122

Draznin, B; Dahl, R; Sherman, N; Sussman, K E; Staehelin, L A

1988-01-01

185

VMP1-deficient Chlamydomonas exhibits severely aberrant cell morphology and disrupted cytokinesis  

PubMed Central

Background The versatile Vacuole Membrane Protein 1 (VMP1) has been previously investigated in six species. It has been shown to be essential in macroautophagy, where it takes part in autophagy initiation. In addition, VMP1 has been implicated in organellar biogenesis; endo-, exo- and phagocytosis, and protein secretion; apoptosis; and cell adhesion. These roles underly its proven involvement in pancreatitis, diabetes and cancer in humans. Results In this study we analyzed a VMP1 homologue from the green alga Chlamydomonas reinhardtii. CrVMP1 knockdown lines showed severe phenotypes, mainly affecting cell division as well as the morphology of cells and organelles. We also provide several pieces of evidence for its involvement in macroautophagy. Conclusion Our study adds a novel role to VMP1's repertoire, namely the regulation of cytokinesis. Though the directness of the observed effects and the mechanisms underlying them remain to be defined, the protein's involvement in macroautophagy in Chlamydomonas, as found by us, suggests that CrVMP1 shares molecular characteristics with its animal and protist counterparts. PMID:24885763

2014-01-01

186

Cadherin-Dependent Cell Morphology in an Epithelium: Constructing a Quantitative Dynamical Model  

PubMed Central

Cells in the Drosophila retina have well-defined morphologies that are attained during tissue morphogenesis. We present a computer simulation of the epithelial tissue in which the global interfacial energy between cells is minimized. Experimental data for both normal cells and mutant cells either lacking or misexpressing the adhesion protein N-cadherin can be explained by a simple model incorporating salient features of morphogenesis that include the timing of N-cadherin expression in cells and its temporal relationship to the remodeling of cell-cell contacts. The simulations reproduce the geometries of wild-type and mutant cells, distinguish features of cadherin dynamics, and emphasize the importance of adhesion protein biogenesis and its timing with respect to cell remodeling. The simulations also indicate that N-cadherin protein is recycled from inactive interfaces to active interfaces, thereby modulating adhesion strengths between cells. PMID:21814505

Gemp, Ian M.; Carthew, Richard W.; Hilgenfeldt, Sascha

2011-01-01

187

A morphological study of 608 cases of canine malignant lymphoma in France with a focus on comparative similarities between canine and human lymphoma morphology.  

PubMed

This study reports cytomorphological, histomorphological, and immunological characterization of 608 biopsy cases of canine malignant lymphoma, with epidemiological and clinical data, collected from 7 French veterinary pathology laboratories. It compares morphological characteristics of malignant lymphoma in canines, per the updated Kiel classification system, with those reported in humans, per the World Health Organization (WHO) classification system. Of tumors described, 24.5% and 75.5% were classified as low- and high-grade malignant lymphomas, respectively. Presenting clinical signs included generalized or localized lymphadenopathy (82.4%) and extranodal diseases (17.6%) involving the skin (12.34%) and other sites (5.26%). Immunohistochemistry confirmed 63.8% B-cell (CD3-, CD79a+), 35.4% T-cell (CD3+, CD79a-), and 0.8% null-cell (CD3-, CD79a-) lymphomas. Most B-cell cases (38.49%) were of high-grade centroblastic polymorphic subtype; most T-cell cases (8.55%), high-grade pleomorphic mixed and large T-cell lymphoma subtypes. Some B-cell tumors showed morphologic characteristics consistent with follicular lymphomas and marginal zone lymphomas per the Revised European American Classification of Lymphoid Neoplasms and WHO canine classification systems and the WHO human classification system. Unusual high-grade B-cell subtypes included an atypical high-grade small B-cell lymphoma (0.66%), Burkitt-type B-cell lymphoma (1.64%), plasmacytoid lymphoma (0.99%), and mediastinal anaplastic large B-cell lymphoma (0.16%). Unusual T-cell subtypes included a previously undescribed high-grade canine immunoblastic T-cell type (1.15%), a rare low-grade prolymphocytic T-cell lymphoma (0.16%), and a recently described high-grade canine T-cell entity--aggressive granulocytic large-cell lymphoma (0.16%). Marginal zone lymphomas were common (10.86%); follicular lymphomas were rare (0.49%). Canine primary cutaneous malignant lymphoma subtypes were present (11.84%). There was no significant difference between B- and T-cell malignant lymphoma in regard to canine age and sex. A significant overrepresentation of Boxers (24.19%) was found for T-cell lymphomas. PMID:20472804

Ponce, F; Marchal, T; Magnol, J P; Turinelli, V; Ledieu, D; Bonnefont, C; Pastor, M; Delignette, M L; Fournel-Fleury, C

2010-05-01

188

The pineal complex in the cichlid Cichlasoma dimerus: effect of different photoperiods on its cell morphology.  

PubMed

This research describes the pineal complex histology in juvenile and adult Cichlasoma dimerus, and the effect of different photoperiods on its cell morphology. In both juveniles and adults, the pineal complex of C. dimerus has three components: the pineal organ, consisting of a pineal vesicle (PV) and a pineal stalk, the parapineal organ and the dorsal sac. Although a strong morphological resemblance exists between the two stages, different synthesis patterns of cone and rod opsins were detected in the two life stages. An effect of the photoperiod length was observed on putative pinealocytes' activity from the PV, measured indirectly through nuclear area morphometry. Individuals exposed to a natural photoperiod (14L:10D) had smaller nuclear areas (mean?±?s.e. = 13·82?±?1·52 µm(2) ) than those exposed to a short photoperiod (8:16) (21·45?±?2·67 µm(2) ; P?study of melatonin synthesis in fish larvae or small adult fishes. PMID:24976599

Birba, A; Ramallo, M R; Morandini, L; Villafańe, V; Tubert, C; Guimarăes Moreira, R; Pandolfi, M

2014-09-01

189

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

PubMed Central

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

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

2011-01-01

190

Study cell invasion by optical techniques  

NASA Astrophysics Data System (ADS)

Cancer is a world-wide health problem associated with an increasing death rate. The mechanisms of how normal cells transform into cancer cells are not fully understood. Intensive investigations have been undertaken to identify genes whose unregulated expression are involved in this process. In this study, we have grown, on collagen gel, adherent mouse embryo fibroblasts (MEFs) knocked out for Cyl-1 (MEF Cyl1-/-) which have been transfected with the human proto-oncogene cyclin D1 (CCND1) under the control of an inducible expression system. CCND1 expression can be regulated in the fibroblasts via the presence of an inducer, isopropyl ?-D-Thiogalactopyranoside (IPTG). In the absence of IPTG, CCND1 expression is silenced. The migration ability of the resultant cells on the collagen gel has been monitored by complementary optical techniques: the conventional light microscopy; optical coherence tomography and Fourier Transform Infrared Microspcopic Spectroscopy (FTIR) using Synchrotron beam source. It is found that the cells expressing CCND1 exhibited cell invasion morphology and had different matrix compositions near the cell layer in comparison to the cells not expressing CCND1. The results from this study are consistent with published findings that expression of CCND1 has oncogenic potential and is involved in cell invasion in vitro. Application of complementary optical techniques proves to be an efficient way obtaining morphological and composition information of cell invasion.

Yang, Ying; Hoban, Paul R.; Sule-Suso, Joseph; Holley, Sarah; El Haj, Alicia J.; Bahrami, Fariba; Wang, Ruikang K.

2006-02-01

191

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

192

A viscometric study of tuning micellar morphology by organic additives  

Microsoft Academic Search

The micellar morphology in aqueous 0.2 M sodium dodecyl sulfate (SDS) solutions has been studied in the simultaneous presence\\u000a of organic salts (anilinium hydrochloride, AHC; ortho-toluidine hydrochloride, oTHC; para-toluidine hydrochloride, pTHC) and aliphatic alcohols (n-butanol, C4OH; n-pentanol, C5OH; n-hexanol, C6OH; n-heptanol, C7OH), aliphatic amines (n-butylamine, C4NH2; n-pentylamine, C5NH2; n-hexylamine, C6NH2; n-heptylamine, C7NH2), or hydrocarbons (n-hexane, C6H; n-heptane, C7H) by viscosity measurements

Ziya Ahmad Khan; Sanjeev Kumar; Tanweer Ahmad

2008-01-01

193

The selective role of ECM components on cell adhesion, morphology, proliferation and communication in vitro  

SciTech Connect

Cell binding to the extracellular matrix (ECM) is essential for cell and tissue functions. In this context, each tissue consists of a unique ECM composition, which may be responsible for tissue-specific cell responses. Due to the complexity of ECM-cell interactions—which depend on the interplay of inside-out and outside-in signaling cascades, cell and tissue specificity of ECM-guidance is poorly understood. In this paper, we investigate the role of different ECM components like laminin, fibronectin, and collagen type I with respect to the essential cell behaviour patterns: attachment dynamics such as adhesion kinetic and force, formation of focal adhesion complexes, morphology, proliferation, and intercellular communication. A detailed in vitro comparison of fibroblasts, endothelial cells, osteoblasts, smooth muscle cells, and chondrocytes reveals significant differences in their cell responses to the ECM: cell behaviour follows a cell specific ligand priority ranking, which was independent of the cell type origin. Fibroblasts responded best to fibronectin, chondrocytes best to collagen I, the other cell types best to laminin. This knowledge is essential for optimization of tissue-biomaterial interfaces in all tissue engineering applications and gives insight into tissue-specific cell guidance. -- Highlights: • We analyse the impact of ECM components on cell behaviour in vitro. • We compare five different cell types, using the same culture conditions. • The ECM significantly guides all cell responses. • Cell behaviour follows a cell specific ligand-priority ranking. • This gives insight in tissue formation and is essential for biomedical applications.

Schlie-Wolter, Sabrina, E-mail: s.schlie@lzh.de [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany); Ngezahayo, Anaclet, E-mail: ngezahayo@biophysik.uni-hannover.de [Institute of Biophysics, Leibniz University Hannover, Herrenhäuser Str. 2, Hannover 30419 (Germany); Chichkov, Boris N., E-mail: b.chichkov@lzh.de [Laser Zentrum Hannover e.V., Hollerithallee 8, 30419 Hannover (Germany)

2013-06-10

194

Automatic Robust Neurite Detection and Morphological Analysis of Neuronal Cell Cultures in High-content Screening  

PubMed Central

Cell-based high content screening (HCS) is becoming an important and increasingly favored approach in therapeutic drug discovery and functional genomics. In HCS, changes in cellular morphology and biomarker distributions provide an information-rich profile of cellular responses to experimental treatments such as small molecules or gene knockdown probes. One obstacle that currently exists with such cell-based assays is the availability of image processing algorithms that are capable of reliably and automatically analyzing large HCS image sets. HCS images of primary neuronal cell cultures are particularly challenging to analyze due to complex cellular morphology. Here we present a robust method for quantifying and statistically analyzing the morphology of neuronal cells in HCS images. The major advantages of our method over existing software lie in its capability to correct non-uniform illumination using the contrast-limited adaptive histogram equalization method; segment neuromeres using Gabor-wavelet texture analysis; and detect faint neurites by a novel phase-based neurite extraction algorithm that is invariant to changes in illumination and contrast and can accurately localize neurites. Our method was successfully applied to analyze a large HCS image set generated in a morphology screen for polyglutamine-mediated neuronal toxicity using primary neuronal cell cultures derived from embryos of a Drosophila Huntington’s Disease (HD) model. PMID:20405243

Wu, Chaohong; Schulte, Joost; Sepp, Katharine J.; Littleton, J. Troy

2011-01-01

195

How Specific Is the Connection between Morphological Awareness and Spelling? A Study of French Children  

ERIC Educational Resources Information Center

This study examined the relationship between morphological awareness and spelling. We show that French children in Grades 3 and 4 appear to use morphological information in spelling; spelling of sounds for which there are several alternatives was more accurate in derived than in nonderived words. The link between morphological awareness and…

Casalis, S.; Deacon, S. H.; Pacton, S.

2011-01-01

196

Stable morphology, but dynamic internal reorganisation, of interphase human chromosomes in living cells.  

PubMed

Despite the distinctive structure of mitotic chromosomes, it has not been possible to visualise individual chromosomes in living interphase cells, where chromosomes spend over 90% of their time. Studies of interphase chromosome structure and dynamics use fluorescence in-situ hybridisation (FISH) on fixed cells, which potentially damages structure and loses dynamic information. We have developed a new methodology, involving photoactivation of labelled histone H3 at mitosis, to visualise individual and specific human chromosomes in living interphase cells. Our data revealed bulk chromosome volume and morphology are established rapidly after mitosis, changing only incrementally after the first hour of G1. This contrasted with the behaviour of specific loci on labelled chromosomes, which showed more progressive reorganisation, and revealed that "looping out" of chromatin from chromosome territories is a dynamic state. We measured considerable heterogeneity in chromosome decondensation, even between sister chromatids, which may reflect local structural impediments to decondensation and could potentially amplify transcriptional noise. Chromosome structure showed tremendous resistance to inhibitors of transcription, histone deacetylation and chromatin remodelling. Together, these data indicate steric constraints determine structure, rather than innate chromosome architecture or function-driven anchoring, with interphase chromatin organisation governed primarily by opposition between needs for decondensation and the space available for this to happen. PMID:20644634

Müller, Iris; Boyle, Shelagh; Singer, Robert H; Bickmore, Wendy A; Chubb, Jonathan R

2010-01-01

197

IRetinal Organization in the retinal degeneration 10 (rd10) Mutant Mouse: a Morphological and ERG Study  

PubMed Central

Retinal degeneration 10 (rd10) mice are a model of autosomal recessive Retinitis Pigmentosa (RP), identified by Chang et al. in 2002. These mice carry a spontaneous mutation of the rod-phosphodiesterase (PDE) gene, leading to a rod degeneration that starts around P18. Later, cones are also lost. Because of photoreceptor degeneration does not overlap with retinal development, and light responses can be recorded for about a month after birth, rd10 mice mimic typical human RP more closely than the well-known rd1 mutants. Aim of this study is to provide a comprehensive analysis of the morphology and function of the rd10 mouse retina during the period of maximum photoreceptor degeneration, thus contributing useful data for exploiting this novel model to study RP. We analyze the morphology and survival of retinal cells in rd10 mice of various ages with quantitative immunocytochemistry and confocal microscopy; we also study retinal function with the electroretinogram (ERG), recorded between P18 and P30. We find that photoreceptor death (peaking around P25) is accompanied and followed by dendritic retraction in bipolar and horizontal cells, which eventually undergo secondary degeneration. ERG reveals alterations in the physiology of the inner retina as early as P18 (before any obvious morphological change of inner neurons) and yet consistently with a reduced band amplification by bipolar cells. Thus, changes in the rd10 retina are very similar to what previously found in rd1 mutants. However, an overall slower decay of retinal structure and function predict that rd10 mice might become excellent models for rescue approaches. PMID:17111372

Gargini, Cludia; Terzibasi, Eva; Mazzoni, Francesca; Strettoi, Enrica

2008-01-01

198

Tyrosine 807 of the v-Fms oncogene product controls cell morphology and association with p120RasGAP.  

PubMed Central

Expression of the v-fms oncogene of feline sarcoma virus in fibroblasts causes surface exposure of an activated receptor tyrosine kinase, v-Fms, that is autophosphorylated at multiple sites within its cytoplasmic domain. Cellular proteins interacting with this part of v-Fms modulate the mitogenic activity and morphology of the cells. We show here that the tyrosine residue in position 807 (Y-807) of the v-Fms molecule constitutes a major autophosphorylation site. The replacement of this residue by phenylalanine (Y807F mutation) allowed us to functionally dissect v-Fms-specific mitogenic and morphogenic cascades. Cells expressing the mutant v-Fms molecule resembled wild-type (wt) v-Fms-transformed (wt-v-Fms) cells in terms of [3H]thymidine uptake rates and activation of the Ras/Raf-1 mitogenic cascade. Such cells showed, however, a flat morphology and contained intact actin cables and fibronectin network. Our studies indicate that the v-Fms molecule controls cell morphology by a cascade that involves a direct interaction with p120RasGAP and p190RhoGAP: (i) in contrast to wt v-Fms molecules, the Y807F v-Fms protein failed to associate with and phosphorylate p120RasGAP; (ii) tight complexes between p120RasGAP and p190RhoGAP as well as detectable RhoGAP activity were present exclusively in wt-v-Fms cells; and (iii) p190RhoGAP was dispersed throughout the cytoplasm of wt-v-Fms cells, whereas its distribution was restricted to perinuclear regions of cells expressing the mutant v-Fms gene. PMID:7666506

Trouliaris, S; Smola, U; Chang, J H; Parsons, S J; Niemann, H; Tamura, T

1995-01-01

199

Cell morphological ultrastructural changes in various organs from mice exposed by inhalation to sulfur dioxide.  

PubMed

Sulfur dioxide (SO2) is a common air pollutant, present in low concentrations in the community air as well as in higher concentrations in some workplaces. Our previous studies demonstrated that SO2 can cause oxidative stress and DNA damage to multiple organs of mice. However, there was no direct proof if and how the morphological changes are caused by SO2. In this study, the ultrastructural morphologies of lungs, livers, spleens, testis, brains, hearts, and kidneys from mice exposed by inhalation to SO2 at 28.00 +/- 1.98 and 56.00 +/- 3.11 mg/m3 were observed with electron microscopy. Our results show that (1) type II alveolar cells of lungs in SO2-exposure groups had obvious pathological changes including vacuolation of osmiophilic multilamellar bodies, a decrease in microvilli content and mitochondrial pyknosis or swelling, as well as various changes in the structure of the nucleus and chromatin. Meanwhile obvious changes in the mitochondrial and nuclear compartments, in type II alveolar cells were also observed. (2) A series of pathological changes was discovered in hepatic cells in SO2-exposure groups, such as swelling of the nucleus, dispersion of lipid droplets, degenerated mitochondria, and dilatation of rough endoplasmic reticulum. For mice exposed to SO2 at 56 mg/m3, necrosis of hepatocytes with unclear karyotheca or nearly dissolved karyotheca and decreases in organelles were observed. (3) The numbers of apoptotic splenocytes from mice exposed to SO2 were increased by SO2 inhalation in a dose-dependent manner. (4) In SO2-exposure groups, some of the cerebral cortex neurons, many glial cells and nerve fibers were damaged. (5) Mitochondrial swelling, decrease or disappearance of mitochondria crista, myocardial myofibril disorder, various changes of nucleus and chromatin, intercalated discs dissociation, and endothelium edema caused by SO2 exposure in heart tissues were found. In addition, other effects, such as myofibrillar fragmentation and dissolution, some myocardial cell membranes breach, and inflammatory cell infiltration, were observed in groups exposed to SO2 at 56 mg/m3. (6) SO2 exposure induced serious ultrastructural lesions in renal proximal tubular lining cells; moreover glomeruli and distal tubular lining cells were damaged in a dose-dependent manner. (7) Compared with the control group, the basement membranes, various seminiferous cells, as well as spermatozoa, and Sertoli cells of testes were altered in the SO2-exposure groups in a dose-dependent manner. In the aggregate, these results lead to a conclusion that inhalation of SO2 can cause the ultrastructure cellular damage of multiple organs in mice. Thus, inhalation of sulfur dioxide appears to be not only toxic to the respiratory system, but also a systemic toxin as well. PMID:17497532

Meng, Ziqiang; Liu, Yuxiang

2007-05-01

200

Learning Morphological and Phonological Spelling Rules: An Intervention Study  

ERIC Educational Resources Information Center

We looked at the effects of teaching 7- and 8-year-old children morphological and phonological distinctions. Some of those given morphological training and some of those given phonological training were also taught how to represent these distinctions in writing. All 4 intervention groups did better than the control group in a standardized test of…

Nunes, Terezinha; Bryant, Peter; Olsson, Jenny

2003-01-01

201

Morphological and Biomechanical Studies of the Ligamentum arteriosum  

Microsoft Academic Search

Fifteen ligaments taken from individuals aged between 60 and 80 years were used for the study of the histological structure, the composition of the ground substance and the biomechanical behavior. Remnants of the original duct are recognizable in the ligament as artery of the muscular type. What had been the intima is thickened and consists mainly of cell-poor, fiber-rich connective

Gottfried Dohr; Inge Ebner; Eugen Gallasch

1986-01-01

202

Sublethal Concentrations of Carbapenems Alter Cell Morphology and Genomic Expression of Klebsiella pneumoniae Biofilms.  

PubMed

Klebsiella pneumoniae, a Gram-negative bacterium, is normally associated with pneumonia in patients with weakened immune systems. However, it is also a prevalent nosocomial infectious agent that can be found in infected surgical sites and combat wounds. Many of these clinical strains display multidrug resistance. We have worked with a clinical strain of K. pneumoniae that was initially isolated from a wound of an injured soldier. This strain demonstrated resistance to many commonly used antibiotics but sensitivity to carbapenems. This isolate was capable of forming biofilms in vitro, contributing to its increased antibiotic resistance and impaired clearance. We were interested in determining how sublethal concentrations of carbapenem treatment specifically affect K. pneumoniae biofilms both in morphology and in genomic expression. Scanning electron microscopy showed striking morphological differences between untreated and treated biofilms, including rounding, blebbing, and dimpling of treated cells. Comparative transcriptome analysis using RNA sequencing (RNA-Seq) technology identified a large number of open reading frames (ORFs) differentially regulated in response to carbapenem treatment at 2 and 24 h. ORFs upregulated with carbapenem treatment included genes involved in resistance, as well as those coding for antiporters and autoinducers. ORFs downregulated included those coding for metal transporters, membrane biosynthesis proteins, and motility proteins. Quantitative real-time PCR validated the general trend of some of these differentially regulated ORFs. Treatment of K. pneumoniae biofilms with sublethal concentrations of carbapenems induced a wide range of phenotypic and gene expression changes. This study reveals some of the mechanisms underlying how sublethal amounts of carbapenems could affect the overall fitness and pathogenic potential of K. pneumoniae biofilm cells. PMID:25583711

Van Laar, Tricia A; Chen, Tsute; You, Tao; Leung, Kai P

2015-03-01

203

Morphological responses of mitochondria-rich cells to hypersaline environment in the Australian mudskipper, Periophthalmus minutus.  

PubMed

A population of the Australian mudskipper, Periophthalmus minutus, was found to inhabit mudflat that remained uncovered by tide for more than 20 days in some neap tides. During these prolonged emersion periods, P. minutus retreated into burrows containing little water, with a highest recorded salinity of 84 ± 7.4 psu (practical salinity unit). To explore the mechanical basis for this salinity tolerance in P. minutus, we determined the densities of mitochondria-rich cells (MRCs) in the inner and outer opercula and the pectoral fin skin, in comparison with P. takita, [corrected] from an adjacent lower intertidal habitat, and studied morphological responses of MRCs to exposure to freshwater (FW), and 100% (34-35 psu) and 200% seawater (SW). Periophthalmus minutus showed a higher density of MRCs in the inner operculum (3365 ± 821 cells mm(-2)) than in the pectoral fin skin (1428 ± 161) or the outer operculum (1100 ± 986), all of which were higher than the MRC densities in p. takita. [corrected]. No mortality occurred in 100% or 200% SW, but half of the fish died within four days in FW. Neither 200% SW nor FW exposure affected MRC density. Transfer to 200% SW doubled MRC size after 9-14 days with no change in the proportion of MRCs with apical pits or plasma sodium concentration. In contrast, transfer to FW resulted in a rapid closing of pits and a significant reduction in plasma sodium concentration. These results suggest that P. minutus has evolved morphological and physiological mechanisms to withstand hypersaline conditions that they may encounter in their habitat. PMID:22775253

Itoki, Naoko; Sakamoto, Tatsuya; Hayashi, Masahiro; Takeda, Tatsusuke; Ishimatsu, Atsushi

2012-07-01

204

Effects of Vitamin D on Airway Epithelial Cell Morphology and Rhinovirus Replication  

PubMed Central

Vitamin D has been linked to reduced risk of viral respiratory illness. We hypothesized that vitamin D could directly reduce rhinovirus (RV) replication in airway epithelium. Primary human bronchial epithelial cells (hBEC) were treated with vitamin D, and RV replication and gene expression were evaluated by quantitative PCR. Cytokine/chemokine secretion was measured by ELISA, and transepithelial resistance (TER) was determined using a voltohmmeter. Morphology was examined using immunohistochemistry. Vitamin D supplementation had no significant effects on RV replication, but potentiated secretion of CXCL8 and CXCL10 from infected or uninfected cells. Treatment with vitamin D in the form of 1,25(OH)2D caused significant changes in cell morphology, including thickening of the cell layers (median of 46.5 µm [35.0–69.0] vs. 30 µm [24.5–34.2], p<0.01) and proliferation of cytokeratin-5-expressing cells, as demonstrated by immunohistochemical analysis. Similar effects were seen for 25(OH)D. In addition to altering morphology, higher concentrations of vitamin D significantly upregulated small proline-rich protein (SPRR1?) expression (6.3 fold-induction, p<0.01), suggestive of squamous metaplasia. Vitamin D treatment of hBECs did not alter repair of mechanically induced wounds. Collectively, these findings indicate that vitamin D does not directly affect RV replication in airway epithelial cells, but can influence chemokine synthesis and alters the growth and differentiation of airway epithelial cells. PMID:24475177

Brockman-Schneider, Rebecca A.; Pickles, Raymond J.; Gern, James E.

2014-01-01

205

Determining the optimum morphology in high-performance polymer-fullerene organic photovoltaic cells  

NASA Astrophysics Data System (ADS)

The morphology of bulk heterojunction organic photovoltaic cells controls many of the performance characteristics of devices. However, measuring this morphology is challenging because of the small length-scales and low contrast between organic materials. Here we use nanoscale photocurrent mapping, ultrafast fluorescence and exciton diffusion to observe the detailed morphology of a high-performance blend of PTB7:PC71BM. We show that optimized blends consist of elongated fullerene-rich and polymer-rich fibre-like domains, which are 10-50?nm wide and 200-400?nm long. These elongated domains provide a concentration gradient for directional charge diffusion that helps in the extraction of charge pairs with 80% efficiency. In contrast, blends with agglomerated fullerene domains show a much lower efficiency of charge extraction of ~45%, which is attributed to poor electron and hole transport. Our results show that the formation of narrow and elongated domains is desirable for efficient bulk heterojunction solar cells.

Hedley, Gordon J.; Ward, Alexander J.; Alekseev, Alexander; Howells, Calvyn T.; Martins, Emiliano R.; Serrano, Luis A.; Cooke, Graeme; Ruseckas, Arvydas; Samuel, Ifor D. W.

2013-12-01

206

Effects of FGF-2 on human adipose tissue derived adult stem cells morphology and chondrogenesis enhancement in Transwell culture  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer We investigated effects of FGF-2 on hADSCs. Black-Right-Pointing-Pointer We examine changes in the level of gene expressions of SOX-9, aggrecan and collagen type II and type X. Black-Right-Pointing-Pointer FGF-2 induces chondrogenesis in hADSCs, which Bullet Increasing information will decrease quality if hospital costs are very different. Black-Right-Pointing-Pointer The result of this study may be beneficial in cartilage tissue engineering. -- Abstract: Injured cartilage is difficult to repair due to its poor vascularisation. Cell based therapies may serve as tools to more effectively regenerate defective cartilage. Both adult mesenchymal stem cells (MSCs) and human adipose derived stem cells (hADSCs) are regarded as potential stem cell sources able to generate functional cartilage for cell transplantation. Growth factors, in particular the TGF-b superfamily, influence many processes during cartilage formation, including cell proliferation, extracellular matrix synthesis, maintenance of the differentiated phenotype, and induction of MSCs towards chondrogenesis. In the current study, we investigated the effects of FGF-2 on hADSC morphology and chondrogenesis in Transwell culture. hADSCs were obtained from patients undergoing elective surgery, and then cultured in expansion medium alone or in the presence of FGF-2 (10 ng/ml). mRNA expression levels of SOX-9, aggrecan and collagen type II and type X were quantified by real-time polymerase chain reaction. The morphology, doubling time, trypsinization time and chondrogenesis of hADSCs were also studied. Expression levels of SOX-9, collagen type II, and aggrecan were all significantly increased in hADSCs expanded in presence of FGF-2. Furthermore FGF-2 induced a slender morphology, whereas doubling time and trypsinization time decreased. Our results suggest that FGF-2 induces hADSCs chondrogenesis in Transwell culture, which may be beneficial in cartilage tissue engineering.

Kabiri, Azadeh, E-mail: z_kabiri@resident.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of)] [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Esfandiari, Ebrahim, E-mail: esfandiari@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of)] [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Hashemibeni, Batool, E-mail: hashemibeni@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of)] [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Kazemi, Mohammad, E-mail: m_kazemi@med.mui.ac.i [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of)] [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Mardani, Mohammad, E-mail: mardani@med.mui.ac.ir [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of)] [Department of Anatomical Sciences and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences (Iran, Islamic Republic of); Esmaeili, Abolghasem, E-mail: abesmaeili@yahoo.com [Cell, Molecular and Developmental Biology Division, Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan (Iran, Islamic Republic of)] [Cell, Molecular and Developmental Biology Division, Department of Biology, Faculty of Sciences, University of Isfahan, Isfahan (Iran, Islamic Republic of)

2012-07-27

207

Large (>3.8 cm) clear cell renal cell carcinomas are morphologically and immunohistochemically heterogeneous.  

PubMed

Heterogeneity is an inherent event to tumour development that is lately receiving much attention in oncologic research. The topic is being addressed primarily at the molecular level, and results are promising. However, translation to practical medicine is still pending. Our intention in this study is to approach the problem in a series of clear cell renal cell carcinomas with the tools that pathologists use in routine practice. Three randomly selected areas of 48 clear cell renal cell carcinomas prospectively collected in two different institutions were analysed for intratumour heterogeneity. The evaluated parameters were tumour size, cell type (clear vs. eosinophilic), Fuhrman's grade and immunohistochemical expression of carbonic anhydrase IX, BRCA1-associated protein-1 (BAP-1), cyclooxygenase-2 (COX-2) and Ki67. Intratumour heterogeneity was detected in 26 cases (54 %). Cell type, grade and Ki67 index were the parameters more frequently heterogeneous amounting, respectively, 44, 42 and 38 %. Tumour size was a significantly discriminative factor to predict tumour heterogeneity, with a cut-off of 3.8 cm (p?cell type (clear vs. eosinophilic), Fuhrman's grade and Ki67 and COX-2 expression patterns. Carbonic anhydrase 9 and BAP-1 did not show statistical relevance. We conclude that heterogeneity is a common event in clear cell renal cell carcinomas that may be overlooked in cases insufficiently sampled. Tumour size appears as a reliable tool in identifying this situation since clear cell renal cell carcinomas under 3.8 cm in diameter are always homogeneous. This point may help the pathologist to make decisions in tumour sampling. PMID:25369891

Zaldumbide, Laura; Erramuzpe, Asier; Guarch, Rosa; Cortés, Jesús M; López, José I

2015-01-01

208

Analogies and differences between quasi-static indentation and hypervelocity impact morphologies on thin solar cells  

Microsoft Academic Search

Morphologies produced by quasi-static indentation on thin Hubble Space Telescope (HST) solar cells show remarkable similarities to much of the hypervelocity damage sustained by the HST solar array whilst in orbit. Quasi-static indentation tests carried out with blunt and sharp indentors reveal analogies between static and dynamic (hypervelocity) indentation indicating similar fracture mechanics processes over the energy range evaluated. Understanding

Mark K. Herbert; Jean-Claude Mandeville; Emma A. Taylor; J. Anthony M. Mcdonnell

2001-01-01

209

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

210

Correlation of ?-conjugated oligomer structure with film morphology and organic solar cell performance.  

PubMed

The novel methyl-substituted dicyanovinyl-capped quinquethiophenes 1-3 led to highly efficient organic solar cells with power conversion efficiencies of 4.8-6.9%. X-ray analysis of single crystals and evaporated neat and blend films gave insights into the packing and morphological behavior of the novel compounds that rationalized their improved photovoltaic performance. PMID:22694124

Fitzner, Roland; Mena-Osteritz, Elena; Mishra, Amaresh; Schulz, Gisela; Reinold, Egon; Weil, Matthias; Körner, Christian; Ziehlke, Hannah; Elschner, Chris; Leo, Karl; Riede, Moritz; Pfeiffer, Martin; Uhrich, Christian; Bäuerle, Peter

2012-07-11

211

Electrospun scaffold topography affects endothelial cell proliferation, metabolic activity, and morphology.  

PubMed

A family of methacrylic terpolymer biomaterials was electrospun into three-dimensional fibrous scaffolds. The glass transition temperature of the polymer correlates with the morphology of the resulting scaffold. Glassy materials produce scaffolds with discrete fibers and a high percent void space (84%) while the rubbery materials produced scaffolds with fused fibers and a much lower percent void space (18%). By electrospinning onto a rotating mandrel, aligned fiber scaffolds were fabricated, and it was shown that controlling the rotation speed of the collector allowed for control over the degree of fiber alignment. The electrospinning was shown to not degrade the number average molecular weight of the polymer chains. Human umbilical vein endothelial cells (HUVECs) were seeded onto the electrospun scaffolds under static conditions and it was found that the morphology of the scaffold controlled the cellular proliferation, the metabolic activity, and the morphology of adherent cells. In particular, HUVECs seeded onto low void space scaffolds exhibited enhanced cellular spreading, enzymatic activity, and proliferation. HUVECs seeded onto aligned fiber scaffolds did not demonstrate increased proliferation; however, the cells did organize themselves in the direction of fiber alignment resulting in cells with elongated morphology. PMID:20694986

Heath, Daniel E; Lannutti, John J; Cooper, Stuart L

2010-09-15

212

Cellular Differentiation in Moss Protonemata: A Morphological and Experimental Study  

PubMed Central

Background and Aims Previous studies of protonemal morphogenesis in mosses have focused on the cytoskeletal basis of tip growth and the production of asexual propagules. This study provides the first comprehensive description of the differentiation of caulonemata and rhizoids, which share the same cytology, and the roles of the cytoskeleton in organelle shaping and spatial arrangement. Methods Light and electron microscope observations were carried out on in vitro cultured and wild protonemata from over 200 moss species. Oryzalin and cytochalasin D were used to investigate the role of the cytoskeleton in the cytological organization of fully differentiated protonemal cells; time-lapse photography was employed to monitor organelle positions. Key Results The onset of differentiation in initially highly vacuolate subapical cells is marked by the appearance of tubular endoplasmic reticulum (ER) profiles with crystalline inclusions, closely followed by an increase in rough endoplasmic reticulum (RER). The tonoplast disintegrates and the original vacuole is replaced by a population of vesicles and small vacuoles originating de novo from RER. The cytoplasm then becomes distributed throughout the cell lumen, an event closely followed by the appearance of endoplasmic microtubules (MTs) in association with sheets of ER, stacks of vesicles that subsequently disperse, elongate mitochondria and chloroplasts and long tubular extensions at both poles of the nucleus. The production of large vesicles by previously inactive dictysomes coincides with the deposition of additional cell wall layers. At maturity, the numbers of endoplasmic microtubules decline, dictyosomes become inactive and the ER is predominantly smooth. Fully developed cells remain largely unaffected by cytochalasin; oryzalin elicits profound cytological changes. Both inhibitors elicit the formation of giant plastids. The plastids and other organelles in fully developed cells are largely stationary. Conclusions Differentiation of caulonemata and rhizoids involves a remarkable series of cytological changes, some of which closely recall major events in sieve element ontogeny in tracheophytes. The cytology of fully differentiated cells is remarkably similar to that of moss food-conducting cells and, in both, is dependent on an intact microtubule cytoskeleton. The disappearance of the major vacuolar apparatus is probably related to the function of caulonema and rhizoids in solute transport. Failure of fully differentiated caulonema and rhizoid cells to regenerate is attributed to a combination of endo-reduplication and irreversible tonoplast fragmentation. The formation of giant plastids, most likely by fusion, following both oryzalin and cytochalasin treatments, suggests key roles for both microtubules and microfilaments in the spatial arrangement and replication of plastids. PMID:18508779

Pressel, Silvia; Ligrone, Roberto; Duckett, Jeffrey G.

2008-01-01

213

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

PubMed

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

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

2008-06-01

214

Resolving Tumor Heterogeneity: Genes Involved in Chordoma Cell Development Identified by Low-Template Analysis of Morphologically Distinct Cells  

PubMed Central

The classical sacrococcygeal chordoma tumor presents with a typical morphology of lobulated myxoid tumor tissue with cords, strands and nests of tumor cells. The population of cells consists of small non-vacuolated cells, intermediate cells with a wide range of vacuolization and large heavily vacuolated (physaliferous) cells. To date analysis was only performed on bulk tumor mass because of its rare incidence, lack of suited model systems and technical limitations thereby neglecting its heterogeneous composition. We intended to clarify whether the observed cell types are derived from genetically distinct clones or represent different phenotypes. Furthermore, we aimed at elucidating the differences between small non-vacuolated and large physaliferous cells on the genomic and transcriptomic level. Phenotype-specific analyses of small non-vacuolated and large physaliferous cells in two independent chordoma cell lines yielded four candidate genes involved in chordoma cell development. UCHL3, coding for an ubiquitin hydrolase, was found to be over-expressed in the large physaliferous cell phenotype of MUG-Chor1 (18.7-fold) and U-CH1 (3.7-fold) cells. The mannosyltransferase ALG11 (695-fold) and the phosphatase subunit PPP2CB (18.6-fold) were found to be up-regulated in large physaliferous MUG-Chor1 cells showing a similar trend in U-CH1 cells. TMEM144, an orphan 10-transmembrane family receptor, yielded contradictory data as cDNA microarray analysis showed up- but RT-qPCR data down-regulation in large physaliferous MUG-Chor1 cells. Isolation of few but morphologically identical cells allowed us to overcome the limitations of bulk analysis in chordoma research. We identified the different chordoma cell phenotypes to be part of a developmental process and discovered new genes linked to chordoma cell development representing potential targets for further research in chordoma tumor biology. PMID:24503940

Wagner, Karin; Meditz, Katharina; Kolb, Dagmar; Feichtinger, Julia; Thallinger, Gerhard G.; Quehenberger, Franz; Liegl-Atzwanger, Bernadette; Rinner, Beate

2014-01-01

215

Relation between substrate surface morphology and microcrystalline silicon solar cell performance  

Microsoft Academic Search

In the present paper, the structural and electrical performances of microcrystalline silicon (?c-Si:H) single junction solar cells co-deposited on a series of substrates having different surface morphologies varying from V-shaped to U-shaped valleys, are analyzed. Transmission electron microscopy (TEM) is used to quantify the density of cracks within the cells deposited on the various substrates. Standard 1 sun, variable illumination

Martin Python; Evelyne Vallat-Sauvain; Julien Bailat; Didier Dominé; Luc Fesquet; Arvind Shah; Christophe Ballif

2008-01-01

216

Biophysical and morphological effects of nanodiamond/nanoplatinum solution (DPV576) on metastatic murine breast cancer cells in vitro.  

PubMed

Nanoparticles have recently gained increased attention as drug delivery systems for the treatment of cancer due to their minute size and unique chemical properties. However, very few studies have tested the biophysical changes associated with nanoparticles on metastatic cancer cells at the cellular and sub-cellular scales. Here, we investigated the mechanical and morphological properties of cancer cells by measuring the changes in cell Young's Modulus using AFM, filopodial retraction (FR) by time lapse optical light microscopy imaging and filopodial disorganization by high resolution AFM imaging of cells upon treatment with nanoparticles. In the current study, nanomechanical changes in live murine metastatic breast cancer cells (4T1) post exposure to a nanodiamond/nanoplatinum mixture dispersed in aqueous solution (DPV576), were monitored. Results showed a decrease in Young's modulus at two hours post treatment with DPV576 in a dose dependent manner. Partial FR at 20 min and complete FR at 40 min were observed. Moreover, analysis of the retraction distance (in microns) measured over time (minutes), showed that a DPV576 concentration of 15%v/v yielded the highest FR rate. In addition, DPV576 treated cells showed early signs of filopodial disorganization and disintegration. This study demonstrates the changes in cell stiffness and tracks early structural alterations of metastatic breast cancer cells post treatment with DPV576, which may have important implications in the role of nanodiamond/nanoplatinum based cancer cell therapy and sensitization to chemotherapy drugs. PMID:25360614

Ghoneum, Alia; Zhu, Huanqi; Woo, JungReem; Zabinyakov, Nikita; Sharma, Shivani; Gimzewski, James K

2014-11-21

217

Biophysical and morphological effects of nanodiamond/nanoplatinum solution (DPV576) on metastatic murine breast cancer cells in vitro  

NASA Astrophysics Data System (ADS)

Nanoparticles have recently gained increased attention as drug delivery systems for the treatment of cancer due to their minute size and unique chemical properties. However, very few studies have tested the biophysical changes associated with nanoparticles on metastatic cancer cells at the cellular and sub-cellular scales. Here, we investigated the mechanical and morphological properties of cancer cells by measuring the changes in cell Young’s Modulus using AFM, filopodial retraction (FR) by time lapse optical light microscopy imaging and filopodial disorganization by high resolution AFM imaging of cells upon treatment with nanoparticles. In the current study, nanomechanical changes in live murine metastatic breast cancer cells (4T1) post exposure to a nanodiamond/nanoplatinum mixture dispersed in aqueous solution (DPV576), were monitored. Results showed a decrease in Young’s modulus at two hours post treatment with DPV576 in a dose dependent manner. Partial FR at 20 min and complete FR at 40 min were observed. Moreover, analysis of the retraction distance (in microns) measured over time (minutes), showed that a DPV576 concentration of 15%v/v yielded the highest FR rate. In addition, DPV576 treated cells showed early signs of filopodial disorganization and disintegration. This study demonstrates the changes in cell stiffness and tracks early structural alterations of metastatic breast cancer cells post treatment with DPV576, which may have important implications in the role of nanodiamond/nanoplatinum based cancer cell therapy and sensitization to chemotherapy drugs.

Ghoneum, Alia; Zhu, Huanqi; Woo, JungReem; Zabinyakov, Nikita; Sharma, Shivani; Gimzewski, James K.

2014-11-01

218

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

PubMed

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

Peichl, L; González-Soriano, J

1994-01-01

219

Morphological study of the palatal rugae in western Indian population.  

PubMed

The aim of this study was to identify and compare the different morphological rugae patterns in males and females of western Indian population, which may be an additional method of identification in cases of crimes or aircraft accidents. A total of 108 plaster casts, equally distributed between the sexes and belonging to similar age-group, were examined for different biometric characteristics of the palatal rugae including number, shape, length, direction and unification and their incidence recorded. Association between these rugae biometric characteristics and sex were tested using chi-square analysis and statistical descriptors were identified for each of these parameters using the SPSS 15.0. The study revealed a statistically significant difference in the total number of rugae between the two sexes (P = 0.000). The different types of rugae between the males and females were statistically compared. The female showed a highly significant difference in the sinuous (P = 0.002) and primary type (P = 0.000) while the male had a significant difference in the unification (P = 0.005). The predominant direction of the rugae was found to be forward relative to backward. It may be concluded that the rugae pattern can be an additional method of differentiation between the male and female in conjunction with the other methods such as visual, fingerprints, and dental characteristics in forensic sciences. PMID:21907934

Gondivkar, Shailesh M; Patel, Swetal; Gadbail, Amol R; Gaikwad, Rahul N; Chole, Revant; Parikh, Rima V

2011-10-01

220

Hybrid morphology dependence of CdTe:CdSe bulk-heterojunction solar cells.  

PubMed

A nanocrystal thin-film solar cell operating on an exciton splitting pattern requires a highly efficient separation of electron-hole pairs and transportation of separated charges. A hybrid bulk-heterojunction (HBH) nanostructure providing a large contact area and interpenetrated charge channels is favorable to an inorganic nanocrystal solar cell with high performance. For this freshly appeared structure, here in this work, we have firstly explored the influence of hybrid morphology on the photovoltaic performance of CdTe:CdSe bulk-heterojunction solar cells with variation in CdSe nanoparticle morphology. Quantum dot (QD) or nanotetrapod (NT)-shaped CdSe nanocrystals have been employed together with CdTe NTs to construct different hybrid structures. The solar cells with the two different hybrid active layers show obvious difference in photovoltaic performance. The hybrid structure with densely packed and continuously interpenetrated two phases generates superior morphological and electrical properties for more efficient inorganic bulk-heterojunction solar cells, which could be readily realized in the NTs:QDs hybrid. This proved strategy is applicable and promising in designing other highly efficient inorganic hybrid solar cells. PMID:25386107

Tan, Furui; Qu, Shengchun; Zhang, Weifeng; Wang, Zhanguo

2014-01-01

221

Hybrid morphology dependence of CdTe:CdSe bulk-heterojunction solar cells  

NASA Astrophysics Data System (ADS)

A nanocrystal thin-film solar cell operating on an exciton splitting pattern requires a highly efficient separation of electron-hole pairs and transportation of separated charges. A hybrid bulk-heterojunction (HBH) nanostructure providing a large contact area and interpenetrated charge channels is favorable to an inorganic nanocrystal solar cell with high performance. For this freshly appeared structure, here in this work, we have firstly explored the influence of hybrid morphology on the photovoltaic performance of CdTe:CdSe bulk-heterojunction solar cells with variation in CdSe nanoparticle morphology. Quantum dot (QD) or nanotetrapod (NT)-shaped CdSe nanocrystals have been employed together with CdTe NTs to construct different hybrid structures. The solar cells with the two different hybrid active layers show obvious difference in photovoltaic performance. The hybrid structure with densely packed and continuously interpenetrated two phases generates superior morphological and electrical properties for more efficient inorganic bulk-heterojunction solar cells, which could be readily realized in the NTs:QDs hybrid. This proved strategy is applicable and promising in designing other highly efficient inorganic hybrid solar cells.

Tan, Furui; Qu, Shengchun; Zhang, Weifeng; Wang, Zhanguo

2014-10-01

222

Testicular fibrothecoma: a morphologic and immunohistochemical study of 16 cases.  

PubMed

Benign intratesticular spindle cell lesions are rare. Herein, we report the morphology, immunohistochemical characteristics, and prognosis of 16 cases of testicular fibrothecoma. The mean age at diagnosis was 44 years (16 to 69 y). Of 15 patients with information, 14 presented with a palpable testicular mass and 1 with heaviness in the scrotum. Medical histories included bilateral orchidopexy as a child (n=1) and testicular atrophy receiving testosterone replacement (n=1). The average size was 1.8 cm (median 2 cm; range, 0.5 to 7.6 cm). All cases were intratesticular, although 13 were abutting the tunica albuginea with others centered on the rete testis (n=2), or were indeterminate on biopsy (n=1). Eleven cases were relatively well circumscribed, although not encapsulated, with 1 being infiltrative and 4 not evaluable. Four tumors showed entrapment of seminiferous tubules. Half of the fibrothecomas showed a mixed storiform pattern and short fascicles, with 6 storiform only and 2 short fascicles only. One half of the tumors were very hypercellular. Cases were equally split between having plumper ovoid as opposed to spindled pointed nuclei, with all cases lacking prominent nucleoli. Eleven cases had 0 to 2 mitoses per 10 HPF, 3 had 4 to 5 mitoses per 10 HPF, and 2 had 9 to 10 mitoses per 10 HPF. Collagen deposition either in bands or investing single cells ranged from none to extensive, with 10/16 cases having at least a moderate amount. Immunohistochemical positivity was as follows: inhibin (11/13, patchy to diffuse); calretinin (5/9); Melan-A (4/4); pan keratin (5/8); BCL2 (3/4); CD34 (3/8); S100 (4/8); muscle-specific actin (4/4); and desmin (5/8). Patients were followed up for a mean of 71.8 months (range, 3 to 144 mo). All were well with no evidence of disease. Of the 2 men with 9 to 10 mitoses per 10 HPF, 1 died of other causes 5 years and 8 months later, and the other had no evidence of disease at 4 years and 10 months after surgery. In summary, testicular fibrothecomas are rare with somewhat variable histology and can have worrisome histologic features such as minimal invasion into surrounding testis, high cellularity, and increased mitotic rate. Their immunoprofile is variable and typically not diagnostic. Despite some worrisome histologic features, they appear uniformly benign in their behavior. PMID:23715159

Zhang, Miao; Kao, Chia-Sui; Ulbright, Thomas M; Epstein, Jonathan I

2013-08-01

223

CN MORPHOLOGY STUDIES OF COMET 103P/HARTLEY 2  

SciTech Connect

We report on narrowband CN imaging of Comet 103P/Hartley 2 obtained at Lowell Observatory on 39 nights from 2010 July until 2011 January. We observed two features, one generally to the north and the other generally to the south. The CN morphology varied during the apparition: no morphology was seen in July; in August and September, the northern feature dominated and appeared as a mostly face-on spiral; in October, November, and December, the northern and southern features were roughly equal in brightness and looked like more side-on corkscrews; in January, the southern feature was dominant but the morphology was indistinct due to very low signal. The morphology changed smoothly during each night and similar morphology was seen from night to night. However, the morphology did not exactly repeat each rotation cycle, suggesting that there is a small non-principal axis rotation. Based on the repetition of the morphology, we find evidence that the fundamental rotation period was increasing: 16.7 hr from August 13 to 17, 17.2 hr from September 10 to 13, 18.2 hr from October 12 to 19, and 18.7 hr from October 31 to November 7. We conducted Monte Carlo jet modeling to constrain the pole orientation and locations of the active regions based on the observed morphology. Our preliminary, self-consistent pole solution has an obliquity of 10{sup 0} relative to the comet's orbital plane (i.e., it is centered near R.A. = 257{sup 0} and decl. = +67{sup 0} with an uncertainty around this position of about 15{sup 0}) and has two mid-latitude sources, one in each hemisphere.

Knight, Matthew M.; Schleicher, David G., E-mail: knight@lowell.edu [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)

2011-06-15

224

Aberrant synaptic input to retinal ganglion cells varies with morphology in a mouse model of retinal degeneration.  

PubMed

Retinal degeneration describes a group of disorders which lead to progressive photoreceptor cell death, resulting in blindness. As this occurs, retinal ganglion cells (RGCs) begin to develop oscillatory physiological activity. Here we studied the morphological and physiological properties of RGCs in rd1 mice, aged 30-60 days, to determine how this aberrant activity correlates with morphology. Patch-clamp recordings of excitatory and inhibitory currents were performed, then dendritic structures were visualized by infusion of fluorescent dye. Only RGCs with oscillatory activity were selected for further analysis. Oscillatory frequency and power were calculated using power spectral density analysis of recorded currents. Dendritic arbor stratification, total length, and area were measured from confocal microscope image stacks. These measurements were used to sort RGCs by cluster analysis using Ward's Method. This resulted in a total of 10 clusters, with monostratified and bistratified cells having five clusters each. Both populations exhibited correlations between arbor stratification and aberrant inhibitory input, while excitatory input did not vary with arbor distribution. These findings illustrate the relationship between aberrant activity and RGC morphology at early stages of retinal degeneration. PMID:25099614

Yee, Christopher W; Toychiev, Abduqodir H; Ivanova, Elena; Sagdullaev, Botir T

2014-12-15

225

Combined effects of flow-induced shear stress and micropatterned surface morphology on neuronal differentiation of human mesenchymal stem cells.  

PubMed

This study investigated the combined effects of surface morphology and flow-induced shear stress on the neuronal differentiation of human mesenchymal stem cells. First, to examine the effect of surface morphology, three patterns were fabricated using photolithography and compared to the flat substrate. After selecting the most effective surface pattern, flow-induced shear stresses (0.10 and 0.25 Pa) were engaged parallel to the direction of the grooves. The degrees of alignment and neurite outgrowth were measured using digital image processing techniques for up to 10 days. Functional evaluations were also performed by monitoring the intracellular calcium concentration and the expression of synaptophysin, ?-tubulin III, and MAP2. Based on these analyses, the pattern of 5 ?m/5 ?m/3 ?m for groove/ridge/depth, respectively, was selected. Next, shear stresses (0.00, 0.10, 0.25 Pa) were applied to the cells on the selected substrate. The shear stresses affected the expression of those markers. The outgrowth measurements indicated that the shear stresses were effective at day 7. However, the effect of shear stresses tended to decrease at day 10. More cells showed higher calcium concentrations under 0.10 Pa. The alignment was also confirmed. Taken together, these results indicated that a shear stress of 0.10 Pa on the substrate of 5 ?m was most effective. Therefore, such combination of mechanical stimuli and surface pattern is expected to promote neuronal differentiation with regard to functional and morphological changes. PMID:23993713

Jeon, Kang Jin; Park, So Hee; Shin, Ji Won; Kang, Yun Gyeong; Hyun, Jin-Sook; Oh, Min Jae; Kim, Seon Yeon; Shin, Jung-Woog

2014-02-01

226

Three-dimensional morphological imaging of human induced pluripotent stem cells by using low-coherence quantitative phase microscopy  

NASA Astrophysics Data System (ADS)

There is an increasing need for non-invasive imaging techniques in the field of stem cell research. Label-free techniques are the best choice for assessment of stem cells because the cells remain intact after imaging and can be used for further studies such as differentiation induction. To develop a high-resolution label-free imaging system, we have been working on a low-coherence quantitative phase microscope (LC-QPM). LC-QPM is a Linnik-type interference microscope equipped with nanometer-resolution optical-path-length control and capable of obtaining three-dimensional volumetric images. The lateral and vertical resolutions of our system are respectively 0.5 and 0.93 ?m and this performance allows capturing sub-cellular morphological features of live cells without labeling. Utilizing LC-QPM, we reported on three-dimensional imaging of membrane fluctuations, dynamics of filopodia, and motions of intracellular organelles. In this presentation, we report three-dimensional morphological imaging of human induced pluripotent stem cells (hiPS cells). Two groups of monolayer hiPS cell cultures were prepared so that one group was cultured in a suitable culture medium that kept the cells undifferentiated, and the other group was cultured in a medium supplemented with retinoic acid, which forces the stem cells to differentiate. The volumetric images of the 2 groups show distinctive differences, especially in surface roughness. We believe that our LC-QPM system will prove useful in assessing many other stem cell conditions.

Yamauchi, Toyohiko; Kakuno, Yumi; Goto, Kentaro; Fukami, Tadashi; Sugiyama, Norikazu; Iwai, Hidenao; Mizuguchi, Yoshinori; Yamashita, Yutaka

2014-03-01

227

A system for automated, noninvasive, morphology-based evaluation of induced pluripotent stem cell cultures.  

PubMed

Due to the rapid adoption and use of human induced pluripotent stem cells (iPSCs) in recent years, there is a need for new technologies that standardize the evaluation of iPSCs to allow the objective comparison of results across different experiments and groups. In this article, we present a noninvasive, fully automated, and analytical system for morphology-based evaluation of iPSC cultures that consists of time-lapse microscopy and novel image analysis software. The presented system acquires low-light phase-contrast images of iPSC growth collected during a period of several days in culture, measures geometrical- and texture-based features of iPSC colonies throughout time, and derives a set of six biologically relevant features to automatically rank the quality of the cell culture. In a study of 94 iPSC cultures, we demonstrated the accuracy of the system by comparing the automated ranking with an independent expert evaluation based on visual review of the time-lapse movies. To our knowledge, this is the first demonstration of a fully automated and objective assessment of iPSC culture quality using noninvasive methods. PMID:24888327

Maddah, Mahnaz; Shoukat-Mumtaz, Uzma; Nassirpour, Sahar; Loewke, Kevin

2014-10-01

228

Morphological Study of the Newly Designed Cementless Femoral Stem  

PubMed Central

A morphology study was essential to the development of the cementless femoral stem because accurate dimensions for both the periosteal and endosteal canal ensure primary fixation stability for the stem, bone interface, and prevent stress shielding at the calcar region. This paper focused on a three-dimensional femoral model for Asian patients that applied preoperative planning and femoral stem design. We measured various femoral parameters such as the femoral head offset, collodiaphyseal angle, bowing angle, anteversion, and medullary canal diameters from the osteotomy level to 150?mm below the osteotomy level to determine the position of the isthmus. Other indices and ratios for the endosteal canal, metaphyseal, and flares were computed and examined. The results showed that Asian femurs are smaller than Western femurs, except in the metaphyseal region. The canal flare index (CFI) was poorly correlated (r < 0.50) to the metaphyseal canal flare index (MCFI), but correlated well (r = 0.66) with the corticomedullary index (CMI). The diversity of the femoral size, particularly in the metaphyseal region, allows for proper femoral stem design for Asian patients, improves osseointegration, and prolongs the life of the implant. PMID:25025068

Baharuddin, Mohd Yusof; Salleh, Sh-Hussain; Zulkifly, Ahmad Hafiz; Lee, Muhammad Hisyam; Mohd Noor, Alias

2014-01-01

229

Morphological studies on block copolymer modified PA 6 blends  

NASA Astrophysics Data System (ADS)

Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

Poindl, M.; Bonten, C.

2014-05-01

230

Morphological transformations in polymer brushes in binary mixtures: DPD study.  

PubMed

Morphological transformations in polymer brushes in a binary mixture of good and bad solvents are studied using dissipative particle dynamics simulations drawing on a characteristic example of polyisoprene natural rubber in an acetone-benzene mixture. A coarse-grained DPD model of this system is built based on the experimental data in the literature. We focus on the transformation of dense, collapsed brush in bad solvent (acetone) to expanded brush solvated in good solvent (benzene) as the concentration of benzene increases. Compared to a sharp globule-to-coil transition observed in individual tethered chains, the collapsed-to-expanded transformation in brushes is found to be gradual without a prominent transition point. The transformation becomes more leveled as the brush density increases. At low densities, the collapsed brush is highly inhomogeneous and patterned into bunches composed of neighboring chains due to favorable polymer-polymer interaction. At high densities, the brush is expanded even in bad solvent due to steric restrictions. In addition, we considered a model system similar to the PINR-acetone-benzene system, but with the interactions between the solvent components worsened to the limit of miscibility. Enhanced contrast between good and bad solvents facilitates absorption of the good solvent by the brush, shifting the collapsed-to-expanded transformation to lower concentrations of good solvent. This effect is especially pronounced for higher brush densities. PMID:25295697

Cheng, Jianli; Vishnyakov, Aleksey; Neimark, Alexander V

2014-11-01

231

Morphological studies on block copolymer modified PA 6 blends  

SciTech Connect

Recent studies show that compounding polyamide 6 (PA 6) with a PA 6 polyether block copolymers made by reaction injection molding (RIM) or continuous anionic polymerization in a reactive extrusion process (REX) result in blends with high impact strength and high stiffness compared to conventional rubber blends. In this paper, different high impact PA 6 blends were prepared using a twin screw extruder. The different impact modifiers were an ethylene propylene copolymer, a PA PA 6 polyether block copolymer made by reaction injection molding and one made by reactive extrusion. To ensure good particle matrix bonding, the ethylene propylene copolymer was grafted with maleic anhydride (EPR-g-MA). Due to the molecular structure of the two block copolymers, a coupling agent was not necessary. The block copolymers are semi-crystalline and partially cross-linked in contrast to commonly used amorphous rubbers which are usually uncured. The combination of different analysis methods like atomic force microscopy (AFM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) gave a detailed view in the structure of the blends. Due to the partial cross-linking, the particles of the block copolymers in the blends are not spherical like the ones of ethylene propylene copolymer. The differences in molecular structure, miscibility and grafting of the impact modifiers result in different mechanical properties and different blend morphologies.

Poindl, M., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de; Bonten, C., E-mail: marcus.poindl@ikt.uni-stuttgart.de, E-mail: christian.bonten@ikt.uni-stuttgart.de [Institut für Kunststofftechnik, University of Stuttgart (Germany)

2014-05-15

232

Improved efficiency organic photovoltaic cells through morphology control and process modification  

NASA Astrophysics Data System (ADS)

Organic photovoltaic (OPV) cells have drawn great attention due to the potential to produce flexible, light weight, affordable solar cells using polymer organic photovoltaic materials; however, the current power conversion efficiency achieved for these systems is too low for widespread implementation of the technology. Morphology and phase separation are key factors determining the performance of organic photovoltaic cells. Precise control of the size and distribution of the phase-separated photoactive domains is necessary for optimum photon-electron conversion. Polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals have the potential to provide enhanced control of morphology, crystallinity, and phase dispersion in polymeric blend systems. In this work, POSS molecules with different organic functionalities were utilized to control OPV film morphology. The light absorption, crystallinity, and phase separated domain size were evaluated to determine the relationship between POSS structures and film characteristics. The selected POSS molecules were utilized for further device fabrication and performance measurements, with which the POSS enhanced performance was revealed. Furthermore, processing conditions are also important in determining the performance and phase separated morphology of the OPV devices. The effects of solvent vapor annealing and thermal annealing were evaluated in terms of light absorption, crystallinity, long-term stabilitiy, and device performance.

Wu, Qi

233

Optimization of molecular organization and nanoscale morphology for high performance low bandgap polymer solar cells.  

PubMed

Rational design and synthesis of low bandgap (LBG) polymers with judiciously tailored HOMO and LUMO levels have emerged as a viable route to high performance polymer solar cells with power conversion efficiencies (PCEs) exceeding 10%. In addition to engineering the energy-level of LBG polymers, the photovoltaic performance of LBG polymer-based solar cells also relies on the device architecture, in particular the fine morphology of the photoactive layer. The nanoscale interpenetrating networks composed of nanostructured donor and acceptor phases are the key to providing a large donor-acceptor interfacial area for maximizing the exciton dissociation and offering a continuous pathway for charge transport. In this Review Article, we summarize recent strategies for tuning the molecular organization and nanoscale morphology toward an enhanced photovoltaic performance of LBG polymer-based solar cells. PMID:24481029

He, Ming; Wang, Mengye; Lin, Changjian; Lin, Zhiqun

2014-04-21

234

Optimization of molecular organization and nanoscale morphology for high performance low bandgap polymer solar cells  

NASA Astrophysics Data System (ADS)

Rational design and synthesis of low bandgap (LBG) polymers with judiciously tailored HOMO and LUMO levels have emerged as a viable route to high performance polymer solar cells with power conversion efficiencies (PCEs) exceeding 10%. In addition to engineering the energy-level of LBG polymers, the photovoltaic performance of LBG polymer-based solar cells also relies on the device architecture, in particular the fine morphology of the photoactive layer. The nanoscale interpenetrating networks composed of nanostructured donor and acceptor phases are the key to providing a large donor-acceptor interfacial area for maximizing the exciton dissociation and offering a continuous pathway for charge transport. In this Review Article, we summarize recent strategies for tuning the molecular organization and nanoscale morphology toward an enhanced photovoltaic performance of LBG polymer-based solar cells.

He, Ming; Wang, Mengye; Lin, Changjian; Lin, Zhiqun

2014-03-01

235

Morphological regional differences of epithelial cells along the midgut in Diatraea saccharalis Fabricius (Lepidoptera: Crambidae) larvae.  

PubMed

The sugarcane borer, Diatraea saccharalis Fabricius, is a pest to sugarcane and many other crops. This work aims to characterize morphological variability in the epithelial cells (columnar, goblet and regenerative) along the midgut of D. saccharalis larvae. Fragments of the midgut (anterior, middle and posterior regions) were fixed and processed by light and scanning electron microscopy. There are both cytochemical and ultrastructural differences in the morphology of the epithelial cells, depending on their localization along the midgut. The apical surface of columnar cells shows an increase in both number and size of the apical protrusions from the anterior to the posterior midgut regions. There is an increase in the amount of PAS-positive (Periodic Acid-Schiff Reaction) granules detected in the cytoplasm of both the columnar and regenerative cells, from the anterior to the posterior region. The goblet cell apical surface is narrow in the anterior region, and enlarged in the posterior midgut; the chamber's cytoplasm extrusion are small and thin at the apical cavity surface, being thicker, longer and more numerous at the basal portion of the cavity. Our results suggest that the sugarcane borer midgut has two morphologically different regions, the anterior and the posterior; the middle region is a transitional region. PMID:18813743

Pinheiro, Daniela O; Quagio-Grassiotto, Irani; Gregório, Elisa A

2008-01-01

236

The morphologies of breast cancer cell lines in three-dimensionalassays correlate with their profiles of gene expression  

SciTech Connect

3D cell cultures are rapidly becoming the method of choice for the physiologically relevant modeling of many aspects of non-malignant and malignant cell behavior ex vivo. Nevertheless, only a limited number of distinct cell types have been evaluated in this assay to date. Here we report the first large scale comparison of the transcriptional profiles and 3D cell culture phenotypes of a substantial panel of human breast cancer cell lines. Each cell line adopts a colony morphology of one of four main classes in 3D culture. These morphologies reflect, at least in part, the underlying gene expression profile and protein expression patterns of the cell lines, and distinct morphologies were also associated with tumor cell invasiveness and with cell lines originating from metastases. We further demonstrate that consistent differences in genes encoding signal transduction proteins emerge when even tumor cells are cultured in 3D microenvironments.

Kenny, Paraic A.; Lee, Genee Y.; Myers, Connie A.; Neve, RichardM.; Semeiks, Jeremy R.; Spellman, Paul T.; Lorenz, Katrin; Lee, Eva H.; Barcellos-Hoff, Mary Helen; Petersen, Ole W.; Gray, Joe W.; Bissell, MinaJ.

2007-01-31

237

A ROCK Inhibitor Blocks the Inhibitory Effect of Chondroitin Sulfate Proteoglycan on Morphological Changes of Mesenchymal Stromal/Stem Cells into Neuron-Like Cells  

PubMed Central

Chondroitin sulfate proteoglycan (CSPG) inhibits neurite outgrowth of various neuronal cell types, and CSPG-associated inhibition of neurite outgrowth is mediated by the Rho/ROCK pathway. Mesenchymal stromal/stem cells (MSCs) have the potential to differentiate into neuron-like cells under specific conditions and have been shown to differentiate into neuron-like cells by co-treatment with the ROCK inhibitor Y27632 and the hypoxia condition mimicking agent CoCl2. In this study, we addressed the hypothesis that a ROCK inhibitor might be beneficial to regenerate neurons during stem cell therapy by preventing transplanted MSCs from inhibition by CSPG in damaged tissues. Indeed, dose-dependent inhibition by CSPG pretreatment was observed during morphological changes of Wharton’s jelly-derived MSCs (WJ-MSCs) induced by Y27632 alone. The formation of neurite-like structures was significantly inhibited when WJ-MSCs were pre-treated with CSPG before induction under Y27632 plus CoCl2 conditions, and pretreatment with a protein kinase C inhibitor reversed such inhibition. However, CSPG treatment resulted in no significant inhibition of the WJ-MSC morphological changes into neuron-like cells after initiating induction by Y27632 plus CoCl2. No marked changes were detected in expression levels of neuronal markers induced by Y27632 plus CoCl2 upon CSPG treatment. CSPG also blocked the morphological changes of human bone marrow-derived MSCs into neuron-like cells under other neuronal induction condition without the ROCK inhibitor, and Y27632 pre-treatment blocked the inhibitory effect of CSPG. These results suggest that a ROCK inhibitor can be efficiently used in stem cell therapy for neuronal induction by avoiding hindrance from CSPG. PMID:24404335

Lim, Hee-Suk; Joe, Young Ae

2013-01-01

238

The measurement of the morphology of closed cell foams which control the overall thermal conductivity  

SciTech Connect

Means to characterize and measure morphology which affects the solid and radiative contributions in closed cell foams have been developed. From measured two-dimensional intercept area distributions, the actual cell size distribution is calculated. For each of the small-celled polyurethane foams examined, the distribution is narrow, close to the mean cell diameter. From numerical analysis of extreme cell segregation, less than 13% error in the extinction coefficient and the radiative contribution calculated from the mean cell diameter is expected due to cell size distribution. A means to measure the fraction of solid in the strut from strut cross sectional areas is derived. For the small-celled foams analyzed, the fraction of solid in the strut decreases from 0.67 to 0.34 as mean cell diameter decreases from 0.363 mm to 0.109 mm. Smaller celled foams which show a redistribution of polymer from the struts to the cell walls as cell size decreases will exhibit a larger solid conductivity which may counterbalance the decrease in radiation which accompanies the small cell size.

Glicksman, L.R.; Stewart, J. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

1997-11-01

239

Human Cancer Classification: A Systems Biology- Based Model Integrating Morphology, Cancer Stem Cells, Proteomics, and Genomics  

PubMed Central

Human cancer classification is currently based on the idea of cell of origin, light and electron microscopic attributes of the cancer. What is not yet integrated into cancer classification are the functional attributes of these cancer cells. Recent innovative techniques in biology have provided a wealth of information on the genomic, transcriptomic and proteomic changes in cancer cells. The emergence of the concept of cancer stem cells needs to be included in a classification model to capture the known attributes of cancer stem cells and their potential contribution to treatment response, and metastases. The integrated model of cancer classification presented here incorporates all morphology, cancer stem cell contributions, genetic, and functional attributes of cancer. Integrated cancer classification models could eliminate the unclassifiable cancers as used in current classifications. Future cancer treatment may be advanced by using an integrated model of cancer classification. PMID:21479129

Idikio, Halliday A

2011-01-01

240

Lectin-mediated effects on bone resorption in vitro: a morphological and functional study  

SciTech Connect

Lectins have been used to study the structure and function of a variety of cells and tissues. The authors used 4 different lectins, concanavalin A (con A), wheat germ agglutinin (WGA), soybean agglutinin (SBA) and peanut agglutinin (PNA) as in vitro biological probes to study the osteoclast, a multinucleated bone cell that is widely accepted as the primary effector cell responsible for normal bone resorption. They evaluated the effects of each of these lectins on osteoclastic bone resorbing activity and then examined mechanisms that may be responsible for the activation and/or inhibition of osteoclastic activity. Using con A and hemocyanin, a marker molecule used to visualize cell-bound con A via scanning electron microscopy, they demonstrated that osteoclasts have specific con A binding sites on their cell surface. They conducted a series of /sup 45/Ca bone release assays demonstrating that con A has a dose-dependent biphasic effect on bone resorption; stimulation at low concentrations and inhibition at higher concentrations. The findings suggest that the specificity of lectin binding to cell surface receptors may play an important role in the induction of altered cell function. Recently, cells of the mononuclear phagocyte system have been proposed as surrogates of less readily available osteoclasts. They used a macrophage-devitalized bone culture system to evaluate the effects of con A and SBA on the attachment of macrophages to bone and their subsequent functional activity. The results showed that con A, but not SBA, alters the morphology and function of macrophages on a devitalized bone surface. The results support the hypothesis that certain, specific saccharides regulate the interaction between macrophages and bone.

Popoff, S.N.

1986-01-01

241

Quantification of Dynamic Morphological Drug Responses in 3D Organotypic Cell Cultures by Automated Image Analysis  

PubMed Central

Glandular epithelial cells differentiate into complex multicellular or acinar structures, when embedded in three-dimensional (3D) extracellular matrix. The spectrum of different multicellular morphologies formed in 3D is a sensitive indicator for the differentiation potential of normal, non-transformed cells compared to different stages of malignant progression. In addition, single cells or cell aggregates may actively invade the matrix, utilizing epithelial, mesenchymal or mixed modes of motility. Dynamic phenotypic changes involved in 3D tumor cell invasion are sensitive to specific small-molecule inhibitors that target the actin cytoskeleton. We have used a panel of inhibitors to demonstrate the power of automated image analysis as a phenotypic or morphometric readout in cell-based assays. We introduce a streamlined stand-alone software solution that supports large-scale high-content screens, based on complex and organotypic cultures. AMIDA (Automated Morphometric Image Data Analysis) allows quantitative measurements of large numbers of images and structures, with a multitude of different spheroid shapes, sizes, and textures. AMIDA supports an automated workflow, and can be combined with quality control and statistical tools for data interpretation and visualization. We have used a representative panel of 12 prostate and breast cancer lines that display a broad spectrum of different spheroid morphologies and modes of invasion, challenged by a library of 19 direct or indirect modulators of the actin cytoskeleton which induce systematic changes in spheroid morphology and differentiation versus invasion. These results were independently validated by 2D proliferation, apoptosis and cell motility assays. We identified three drugs that primarily attenuated the invasion and formation of invasive processes in 3D, without affecting proliferation or apoptosis. Two of these compounds block Rac signalling, one affects cellular cAMP/cGMP accumulation. Our approach supports the growing needs for user-friendly, straightforward solutions that facilitate large-scale, cell-based 3D assays in basic research, drug discovery, and target validation. PMID:24810913

Härmä, Ville; Schukov, Hannu-Pekka; Happonen, Antti; Ahonen, Ilmari; Virtanen, Johannes; Siitari, Harri; Ĺkerfelt, Malin; Lötjönen, Jyrki; Nees, Matthias

2014-01-01

242

Inflectional morphology in primary progressive aphasia: an elicited production study.  

PubMed

Inflectional morphology lies at the intersection of phonology, syntax and the lexicon, three language domains that are differentially impacted in the three main variants of primary progressive aphasia (PPA). To characterize spared and impaired aspects of inflectional morphology in PPA, we elicited inflectional morphemes in 48 individuals with PPA and 13 healthy age-matched controls. We varied the factors of regularity, frequency, word class, and lexicality, and used voxel-based morphometry to identify brain regions where atrophy was predictive of deficits on particular conditions. All three PPA variants showed deficits in inflectional morphology, with the specific nature of the deficits dependent on the anatomical and linguistic features of each variant. Deficits in inflecting low-frequency irregular words were associated with semantic PPA, with lexical/semantic deficits, and with left temporal atrophy. Deficits in inflecting pseudowords were associated with non-fluent/agrammatic and logopenic variants, with phonological deficits, and with left frontal and parietal atrophy. PMID:25129631

Wilson, Stephen M; Brandt, Temre H; Henry, Maya L; Babiak, Miranda; Ogar, Jennifer M; Salli, Chelsey; Wilson, Lisa; Peralta, Karen; Miller, Bruce L; Gorno-Tempini, Maria Luisa

2014-09-01

243

The effect of photodynamic treatment on the morphological and mechanical properties of the HeLa cell line.  

PubMed

High resolution imaging of biological structures and changes induced by various agents such as drugs and toxins is commonly performed by fluorescence and electron microscopy (EM). Although high-resolution imaging is possible with EM, the requirements for fixation and staining of samples for image contrast severely limits the study of living organisms. Atomic force microscopy (AFM), on the other hand, is capable of simultaneous nanometer spatial resolution and piconewton force detection, allowing detailed study of cell surface morphology and monitoring cytomechanical information. We present a method that images and studies mechanically characterized cells using AFM. We used a HeLa cell line (cervix carcinoma cell), which is sensitive to photodynamic treatment (PDT); growth media as a scanning surrounding; atomic force microscopy NT-MDT Aura for cytomechanical measurement; and scanning electron microscope Hitachi Su 6600 for control images of the cells. The modulus of elasticity for intact and photodynamically damaged cells can indicate mechanical changes to the main properties of cells. Cell elasticity changes can provide information on the degree or value of cell damage, for example after PDT. Measurements were carried out on approximately sixty cells, including three independent experiments on a control group and on sixty cells in a photodamaged group. Cells before PDT show higher elasticity: the median of Young´s modulus on the nucleus was 35.283 kPa and outside of the nucleus 107.442 kPa. After PDT, the median of Young's modulus on the nucleus was 61.144 kPa and outside of the nucleus was 193.605 kPa. PMID:23817636

Kolar, Petr; Tomankova, Katerina; Malohlava, Jakub; Zapletalova, Jana; Vujtek, Milan; Safarova, Klara; Jancik, Dalibor; Kolarova, Hana

2013-09-01

244

Flow cytometry based enrichment for cell shape mutants identifies multiple genes that influence Helicobacter pylori morphology  

PubMed Central

Summary The helical cell shape of Helicobacter pylori is highly conserved and contributes to its ability to swim through and colonize the viscous gastric mucus layer. A multi-faceted peptidoglycan (PG) modification program involving four recently characterized peptidases and two accessory proteins is essential for maintaining H. pylori's helicity. To expedite identification of additional shape-determining genes, we employed flow cytometry with fluorescence-activated cell sorting (FACS) to enrich a transposon library for bacterial cells with altered light scattering profiles that correlate with perturbed cell morphology. After a single round of sorting, 15% of our clones exhibited a stable cell shape defect, reflecting 37-fold enrichment. Sorted clones with straight rod morphology contained insertions in known PG peptidases, as well as an insertion in csd6, which we demonstrated has LD-carboxypeptidase activity and cleaves monomeric tetrapeptides in the PG sacculus, yielding tripeptides. Other mutants had only slight changes in helicity due to insertions in genes encoding MviN/MurJ, a protein possibly involved in initiating PG synthesis, and the hypothetical protein HPG27_782. Our findings demonstrate FACS robustly detects perturbations of bacterial cell shape and identify additional PG peptide modifications associated with helical cell shape in H. pylori. PMID:24112477

Sycuro, Laura K.; Rule, Chelsea S.; Petersen, Timothy W.; Wyckoff, Timna J.; Sessler, Tate; Nagarkar, Dilip B.; Khalid, Fakhra; Pincus, Zachary; Biboy, Jacoby; Vollmer, Waldemar; Salama, Nina R.

2013-01-01

245

Bronchial wash cytology: A study on morphology and morphometry  

PubMed Central

Background: Bronchial wash cytology of lung lesions is a non/minimally invasive procedure utilized for diagnosis of pulmonary lesions. Aim: The aim of this study was to evaluate the efficacy of bronchial wash cytology in the diagnosis of bronchopulmonary lesions and assess the role of morphometry in categorizing dysplastic/malignant lesions. Materials and Methods: All cases of bronchial wash cytology received from January 2006 to June 2010 were retrieved and reviewed. Cases with adequate clinical data or a subsequent biopsy were selected for the study and cytodiagnosis was correlated with available clinical details. Morphometry was done on alcohol fixed hematoxylin and eosin stained cytosmears using computer assisted Image Pro software. Results: One hundred and seventy-six cases of the 373 cases of bronchial cytology received were included for the study. Bronchial wash cytology technique showed high specificity. Cytohistopathology correlation showed 62.06% concordance rate. Cells from normal epithelium, reactive atypia, neoplastic atypia, squamous metaplasia, non-small cell and small cell carcinoma showed a mean nuclear diameter of 7.4 ?m, 11.7 ?m, 13.9 ?m, 13.0 ?m, 10.7 ?m, and 17.7 ?m, respectively, which was statistically significant with P < 0.05. Multiple comparisons between various groups using analysis of variance and Bonferroni tests also showed remarkable statistical significance. Conclusions: Bronchial wash cytology has low sensitivity in detecting pulmonary lesions. It can be of value in patients with contraindication for biopsy. Morphometry can be a useful adjunct to cytomorphology, especially in situations where biopsy is contraindicated. PMID:25210231

Rao, Shalinee; Rao, Shivani; Lal, Archana; Barathi, Gunabooshanam; Dhanasekar, Thangaswamy; Duvuru, Prathiba

2014-01-01

246

Morphological studies of sulfonated polystyrene and sulfonated EPDM ionomers  

SciTech Connect

Two ionomer systems have been investigated in this research. Sulfonated polystyrene (SPS) is a typical random ionomer and is a good material for studies into the nature of phase separation in ionomers. A series of narrow molecular weight distribution (MWD) zinc neutralized SPS samples of varying sulfonation levels were prepared and analyzed through small angle x-ray scattering (SAXS). Results indicated that the correlation distance varied with both molecular weight and sulfonation level. Increases in the position of the scattering maximum with sulfonation level is the result of a greater number of ionic groups. Increasing molecular weight led to the movement of the scattering maximum to smaller scattering vectors, an indication of larger distances. It was also observed that ionomer peak occurred at smaller scattering vectors for the narrow MWD samples than in corresponding materials of greater dispersity. SAXS was also used to examine the morphology of zinc stearate (ZnSt) filled sulfonated EPDM (S-EPDM) ionomers and the nature of the interaction between the plasticizer and the ionomer. S-EPDM is a material that may find use as a thermoplastic elastomer, although its melt viscosity is too high to allow for convenient processing. The addition of of ZnSt as a plasticizer greatly reduces the melt viscosity of S-EPDM. ZnSt exists in this system as very small crystallites which are associated with ionic groups. As the temperature is increased, the crystallites anneal briefly into larger crystals before melting and diffusing into the S-EPDM matrix. Above the melting temperature of the ZnSt, it solvates the ionic groups of the ionomer, decreasing their self-association and the viscosity of the system. Increasing ZnSt loading is seen in the SAXS as an increase in scattering in the low angle region. However, this increase in intensity is not linear with concentration, showing that ZnSt exists in different environments at higher concentrations.

Jackson, D.A.

1992-12-31

247

A unique case of mantle cell lymphoma with an aberrant CD5-/CD10+ immunophenotype and typical morphology.  

PubMed

Mantle cell lymphoma (MCL) is a non-Hodgkin lymphoma with a poor prognosis that may be confused with less aggressive diseases, such as small lymphocytic lymphoma and follicular lymphoma. In many cases immunophenotyping, particularly analysis of reactivity for CD5 and CD10, is an important adjunct to morphology that usually distinguishes MCL from follicular lymphoma; the former is CD5(+)/CD10(-), whereas follicular lymphoma is the reverse. We report a case of MCL, initially diagnosed as follicular lymphoma, that at presentation expressed neither CD5 nor CD10. At relapse, it was still CD5(-), but CD10 was now detected. Studies for a t(11;14) translocation and CYCLIN D1 protein expression, however, permitted a revised diagnosis of MCL. An MCL with this immunophenotype and classical morphology has not been previously reported. PMID:18684040

Sriganeshan, Vathany; Blom, Thomas R; Weissmann, David J

2008-08-01

248

The Latin-Greek Connection: Building Vocabulary through Morphological Study  

ERIC Educational Resources Information Center

In this article, the authors make a case for teaching vocabulary in the elementary grades through a focus on the morphological structure of words, in particular English words that are derived through Latin and Greek roots and affixes. The authors present a set of engaging instructional ideas for the use of Latin and Greek derivations to teach…

Rasinski, Timothy V.; Padak, Nancy; Newton, Joanna; Newton, Evangeline

2011-01-01

249

Morphologically controlled fuel cell transport layers enabled via electrospun carbon nonwovens  

NASA Astrophysics Data System (ADS)

We report on the synthesis and performance of carbon nanofibre substrates for PEM fuel cell transport layer applications. Electrospinning is used for fabrication; by manipulation of spinning properties, morphological control is demonstrated in the product. Our application of the technology and it's manipulability to PEMFC transport layers constitutes a novel approach to the manufacture of such layers. Ex-situ morphology, electrical resistance and water contact angles are reported in additional to in-situ hydrogen/air fuel cell performance. Electrospun transport layers are compared directly to established commercial products in a cathode PTL role. The electrospun transport layers demonstrate approximately 85% of the commercial limiting current density, swifter water transport characteristics, and markedly more stable operating points.

Todd, Devin; Mérida, Walter

2015-01-01

250

The Deschutes Estuary Restoration Feasibility Study: development of a process-based morphological model  

E-print Network

1 The Deschutes Estuary Restoration Feasibility Study: development of a process-based morphological the initial morphology of the basin. As part of the Deschutes River Estuary Restoration Feasibility Study, lake and lower Budd Inlet should estuary restoration occur. Understanding these mechanisms will assist

251

Morphological similarities after compression trauma of bovine and human intervertebral discs: Do disc cells have a chance of surviving?  

PubMed

To study the behavior of bovine disc cells and changes in disc matrix following in vitro compression tests; to compare the findings to investigations on human intervertebral discs (IVD) after burst fracture of the cervical spine. Healthy IVDs (n = 21) from three bovine tails were studied at 6 and 12 h post-mortem, with 16 IVDs subjected to impact loading and five as unloaded controls. IVDs (n = 8) from patients with burst fractures were compared to the bovine compression group. Specimens were studied macroscopically, histologically, and ultrastructurally for healthy cells, balloon cells, and disc cell death (DCD). Annulus ruptures were seen in both post-trauma groups, with radial ruptures being present histologically in all loaded bovine discs. Balloon cells were found in some human IVDs and were induced in vitro in bovine loaded discs within a distinct range of absorbed energy. There was a positive correlation between DCD and absorbed energy in all compartments of bovine discs. Both species showed similar patterns of DCD in the different compartments. This study was able to show similarities between both species in cell morphologies and matrix damage. The survival of the disc after substantial compression trauma thus seems to remain highly questionable. PMID:24888549

Sitte, Ingrid; Kathrein, Anton; Klosterhuber, Miranda; Lindtner, Richard Andreas; Neururer, Sabrina Barbara; Rauch, Stefan; Kuhn, Volker; Schmoelz, Werner

2014-09-01

252

Computational image analysis of colony and nuclear morphology to evaluate human induced pluripotent stem cells.  

PubMed

Non-invasive evaluation of cell reprogramming by advanced image analysis is required to maintain the quality of cells intended for regenerative medicine. Here, we constructed living and unlabelled colony image libraries of various human induced pluripotent stem cell (iPSC) lines for supervised machine learning pattern recognition to accurately distinguish bona fide iPSCs from improperly reprogrammed cells. Furthermore, we found that image features for efficient discrimination reside in cellular components. In fact, extensive analysis of nuclear morphologies revealed dynamic and characteristic signatures, including the linear form of the promyelocytic leukaemia (PML)-defined structure in iPSCs, which was reversed to a regular sphere upon differentiation. Our data revealed that iPSCs have a markedly different overall nuclear architecture that may contribute to highly accurate discrimination based on the cell reprogramming status. PMID:25385348

Tokunaga, Kazuaki; Saitoh, Noriko; Goldberg, Ilya G; Sakamoto, Chiyomi; Yasuda, Yoko; Yoshida, Yoshinori; Yamanaka, Shinya; Nakao, Mitsuyoshi

2014-01-01

253

A direct evidence of morphological degradation on a nanometer scale in polymer solar cells.  

PubMed

In situ measurement of a polymer solar cell using micro grazing incidence small angle X-ray scattering (?GISAXS) and current-voltage tracking is demonstrated. While measuring electric characteristics under illumination, morphological changes are probed by ?GISAXS. The X-ray beam (green) impinges on the photo active layer with a shallow angle and scatters on a 2d detector. Degradation is explained by the ongoing nanomorphological changes observed. PMID:24027092

Schaffer, Christoph J; Palumbiny, Claudia M; Niedermeier, Martin A; Jendrzejewski, Christian; Santoro, Gonzalo; Roth, Stephan V; Müller-Buschbaum, Peter

2013-12-10

254

Penicillin Binding Protein 5 Affects Cell Diameter, Contour, and Morphology of Escherichia coli  

Microsoft Academic Search

Although general physiological functions have been ascribed to the high-molecular-weight penicillin binding proteins (PBPs) of Escherichia coli, the low-molecular-weight PBPs have no well-defined biological roles. When we examined the morphology of a set of E. coli mutants lacking multiple PBPs, we observed that strains ex- pressing active PBP 5 produced cells of normal shape, while mutants lacking PBP 5 produced

DAVID E. NELSON; KEVIN D. YOUNG

2000-01-01

255

Sucralose sweetener does not modify radiolabeling of blood constituents and morphology of red blood cells  

Microsoft Academic Search

Effects of sucralose on the labeling of blood constituents with technetium-99m (99mTc) and on the morphology of red blood cells (RBC) were evaluated. Blood samples from Wistar rats were treated with sweetener, and the labeling of blood constituents with (99mTc) was performed. Radioactivity in blood constituents was counted, and the percentage of incorporated radioactivity (%ATI)\\u000a was determined. Blood smears were

Gabrielle de Souza Rocha; Marcia de Oliveira Pereira; Monica de Oliveira Benarroz; Jacques Natan Grinapel Frydman; Vanessa Câmara da Rocha; Mário José Pereira dos Santos; Adenilson de Souza da Fonseca; Mario Bernardo-Filho

256

Electrophysiological properties of morphologically distinct cells isolated from the rabbit atrioventricular node.  

PubMed Central

1. Experiments were conducted using the whole-cell patch clamp technique to determine the electrophysiological properties and ionic currents of ovoid and rod-shaped single isolated calcium-tolerant rabbit atrioventricular (AV) nodal cells. 2. Action potential morphologies observed in these cells were similar to those obtained previously from intracellular recordings of intact atrioventricular nodal preparations: ovoid cells had N- or NH-like action potential configurations (see below), whereas rod-shaped cells had AN-like configurations. 3. Action potential restitution in AV nodal cells was characterized by a progressive increase in overshoot potential, maximal upstroke velocity (Vmax) and action potential duration, as well as a decrease in latency from stimulus to Vmax. In rod-shaped cells, premature stimuli could induce regenerative membrane responses before full action potential repolarization, whereas ovoid cells showed only post-repolarization refractoriness. In ovoid cells stimulated at the low stimulus intensities there was no shortening of the action potential duration and the most premature action potentials were often prolonged. 4. The quasi-steady-state current-voltage relationship of ovoid cells was significantly steeper, at both depolarized and hyperpolarized potentials, than that of either the rod-shaped AV nodal cells or atrial cells. The rod-shaped AV nodal cells and the atrial cells had similar current-voltage (I-V) relationships in the positive potential range, but the I-V curves crossed over at potentials of about-90 mV. 5. A hyperpolarization-activated inward current (I(f)) was apparent in the range between -60 and -90 mV in 95% of the ovoid cells (n = 75), whereas in 88% of rod-shaped cells (n = 16) I(f) was activated at more negative potentials. The magnitude of I(f) in ovoid cells, measured at -100 mV, was approximately 25 times that in rod-shaped cells. 6. A rapid inward current (INa) greater than 1 nA was found in all rod-shaped cells (n = 16) but in only 30% of ovoid cells (n = 75). A transient outward current (I(to)) was found in 93% of rod-shaped cells (n = 14) and in 42% of ovoid cells (n = 54). The combination of I(to) and INa was found in 93% of rod-shaped cells but in only 24% of ovoid cells. 7. These results suggest that there are at least two populations of isolated AV nodal cells with distinct action potentials and ionic current profiles that may contribute to the complex electrophysiological properties observed in the intact AV node. Images Figure 1 PMID:8799901

Munk, A A; Adjemian, R A; Zhao, J; Ogbaghebriel, A; Shrier, A

1996-01-01

257

Effect of three distinct recombinant cell-binding domains of FN (rCDFN) and substrate crosslinking density on the morphology and dynamics of Human Dermal Fibroblast cells  

NASA Astrophysics Data System (ADS)

Tissue development depends largely on how cells sense and respond to extracellular matrix (ECM). Coupling of cell integrins with ECM ligands generates both, a ligation-induced signaling and a state of isometric tension, within the cell cytoskeleton (CSK). The extent to which ECM supports this prestress governs cell shape and function. In this study, we formulated hydrogels by coupling the three rCDFN to cross-linked thiolated HA backbone using a PEGDA crosslinker. We investigated cell stiffness and the corresponding actin CSK arrangement as a function of hydrogel stiffness and adhesiveness. Hydrogel stiffness was controlled by the amount of crosslinker added, while the adhesiveness was controlled by the nature and amount of the rFNfs coupled to the hydrogel backbone. AFM was used to determine the surface modulus of live cells. Confocal microscope was used to obtain images of the actin CSK of fixed and stained cells. It was found that cells seeded on either stiffer or more adhesive surfaces had larger surface moduli and more stretched actin CSK than those seeded on softer or less adhesive substrates. This indicated that the cortical tension was able to sense both, the underlying substrate stiffness and adhesiveness. Diffusion dynamics of cells seeded on these substrates was also monitored and correlated with cell morphology, substrate stiffness and nature of rCDFN.

Ghosh, K.; Shu, Xz; Ge, S.; Fang, X.; Rafailovich, M.; Prestwich, Gd; Clark, Raf

2004-03-01

258

A computational mechanics approach to assess the link between cell morphology and forces during confined migration.  

PubMed

Confined migration plays a fundamental role during several biological phenomena such as embryogenesis, immunity and tumorogenesis. Here, we propose a two-dimensional mechanical model to simulate the migration of a HeLa cell through a micro-channel. As in our previous works, the cell is modelled as a continuum and a standard Maxwell model is used to describe the mechanical behaviour of both the cytoplasm (including active strains) and the nucleus. The cell cyclically protrudes and contracts and develops viscous forces to adhere to the substrate. The micro-channel is represented by two rigid walls, and it exerts an additional viscous force on the cell boundaries. We test four channels whose dimensions in terms of width are i) larger than the cell diameter, ii) sub-cellular, ii) sub-nuclear and iv) much smaller than the nucleus diameter. The main objective of the work is to assess the necessary conditions for the cell to enter into the channel and migrate through it. Therefore, we evaluate both the evolution of the cell morphology and the cell-channel and cell-substrate surface forces, and we show that there exists a link between the two, which is the essential parameter determining whether the cell is permeative, invasive or penetrating. PMID:24895016

Aubry, D; Thiam, H; Piel, M; Allena, R

2015-01-01

259

A morphological and chemical study of Populus acuminata Rydberg  

Microsoft Academic Search

Evidence from morphology, flavonoid chemistry, and field observations suggests thatPopulus acuminata is of hybrid origin. The putative parents areP. angustifolia, the narrow leaf cottonwood, and deltoid leaved plants that are assigned toP. sargentii (P. deltoides var.occidentalis), P. fremontii, orP. wislizenii (P. fremontii var.wislizenii). Populus angustifolia exhibits a series of flavonol glycosides (kaempferol, quercetin, and myricetin) in its leaves. By contrast,

Daniel J. Crawford

1974-01-01

260

[Functional and morphological studies on diverticulosis of the large bowel].  

PubMed

In comparison to the normal colon, longitudinal and circular musculature in diverticular disease (DD) was investigated--regarding motility and morphology--and a comparative measurement between musculature and mucosa was also performed with following results: 1. Only the tenia in DD revealed a spastically contracted muscle. 2. There was a ribbon formation due to contraction only in tenias of DD, although there was hypertrophy in both muscle groups. 3. The longitudinal muscle in DD was found to be shortened. PMID:456121

Raguse, T; Bubenzer, J

1979-01-01

261

Morphological alterations of T24 cells on flat and nanotubular TiO2 surfaces  

PubMed Central

Aim To investigate morphological alterations of malignant cancer cells (T24) of urothelial origin seeded on flat titanium (Ti) and nanotubular titanium dioxide (TiO2) nanostructures. Methods Using anodization method, TiO2 surfaces composed of vertically aligned nanotubes of 50-100 nm diameters were produced. The flat Ti surface was used as a reference. The alteration in the morphology of cancer cells was evaluated using scanning electron microscopy (SEM). A computational model, based on the theory of membrane elasticity, was constructed to shed light on the biophysical mechanisms responsible for the observed changes in the contact area of adhesion. Results Large diameter TiO2 nanotubes exhibited a significantly smaller contact area of adhesion (P?cell spreading on the large diameter TiO2 nanotubular surface, thus explaining the small contact area. Conclusion The reduction in the cell contact area in the case of large diameter TiO2 nanotube surface, which does not enable formation of the large enough number of the focal adhesion points, prevents spreading of urothelial cells. PMID:23275323

Imani, Roghayeh; Kabaso, Doron; Erdani Kreft, Mateja; Gongadze, Ekaterina; Peni?, Samo; Elerši?, Kristina; Kos, Andrej; Verani?, Peter; Zorec, Robert; Igli?, Aleš

2012-01-01

262

Choline Supplementation Inhibits Diethanolamine-Induced Morphological Transformation in Syrian Hamster Embryo Cells: Evidence for a Carcinogenic Mechanism  

Microsoft Academic Search

DEA, an amino alcohol, and its fatty acid condensates are widely used in commerce. DEA is hepatocarcinogenic in mice, but shows no evidence of mutagenicity or clastogenicity in a standard testing battery. However, it increased the number of morphologi- cally transformed colonies in the Syrian hamster embryo (SHE) cell morphologic transformation assay. The goal of this work was to test

L. D. Lehman-McKeeman

2000-01-01

263

Morphological control in polymer solar cells using low-boiling-point solvent additives  

NASA Astrophysics Data System (ADS)

In the global search for clean, renewable energy sources, organic photovoltaics (OPVs) have recently been given much attention. Popular modern-day OPVs are made from solution-processible, carbon-based polymers (e.g. the model poly(3-hexylthiophene) that are intimately blended with fullerene derivatives (e.g. [6,6]-phenyl-C71-butyric acid methyl ester) to form what is known as the dispersed bulk-heterojunction (BHJ). This BHJ architecture has produced some of the most efficient OPVs to date, with reports closing in on 10% power conversion efficiency. To push efficiencies further into double digits, many groups have identified the BHJ nanomorphology---that is, the phase separations and grain sizes within the polymer: fullerene composite---as a key aspect in need of control and improvement. As a result, many methods, including thermal annealing, slow-drying (solvent) annealing, vapor annealing, and solvent additives, have been developed and studied to promote BHJ self-organization. Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in BHJ OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated.

Mahadevapuram, Rakesh C.

264

A 37-year-old spinal cord-injured female patient, transplanted of multipotent stem cells from human UC blood, with improved sensory perception and mobility, both functionally and morphologically: a case study  

Microsoft Academic Search

HLA-matched UC blood-derived multipotent stem cells were directly transplanted into the injured spinal cord site of a 37-year-old female patient suffering from spinal cord injury (SPI). In this case, human cord blood (UCB)-derived multipotent stem cells improved sensory perception and movement in the SPI patient's hips and thighs within 41 days of cell transplantation. CT and MRI results also showed

K-S Kang; SW Kim; YH Oh; JW Yu; K-Y Kim; C-H Song; H Han

2005-01-01

265

Identification and quantitation of morphological cell types in electrophoretically separated human embryonic kidney cell cultures  

NASA Technical Reports Server (NTRS)

Four major cell types were identified by phase microscopy in early passage human embryonic kidney cell cultures. They are small and large epithelioid, domed, and fenestrated cells. Fibroblasts are also present in some explants. The percent of each cell type changes with passage number as any given culture grows. As a general rule, the fraction of small epithelioid cells increases, while the fraction of fenestrated cells, always small, decreases further. When fibroblasts are present, they always increase in percentage of the total cell population. Electrophoretic separation of early passage cells showed that the domed cells have the highest electrophoretic mobility, fibroblasts have an intermediate high mobility, small epithelioid cells have a low mobility, broadly distributed, and fenestrated cells have the lowest mobility. All cell types were broadly distributed among electrophoretic subfractions, which were never pure but only enriched with respect to a given cell type.

Williams, K. B.; Kunze, M. E.; Todd, P. W.

1985-01-01

266

Morphological and biochemical changes induced by arsenic trioxide in neuroblastoma cell lines.  

PubMed

Arsenic trioxide has recently been shown to inhibit growth and induce apoptosis in a variety of hematologic malignancies, but very little is known about its effects on solid tumors and especially on neuroblastoma cells that have self-differentiating characteristics. To demonstrate the growth inhibition induced in neuroblastoma cells (the SH-SY5Y and SK-N-AS cell line) and acute promyelocytic leukemia cells (HL-60) by arsenic trioxide (As2O3), the viable cell numbers were counted after trypan blue staining. Apoptosis was assessed by the cell morphology, by flow cytometry with annexin-V staining, and by Western blot analysis for the apoptosis-related proteins (bcl-2 and PARP). To decide the dose for the clinical application of As2O3, normal peripheral blood lymphocytes were also examined. The growth and survival of the SH-SY5Y and SK-N-AS cells were markedly inhibited by As2O3 treatment at a 3 microM concentration before the changes of the normal lymphocytes were observed. The apoptotic cells showed a shrunken cell nucleus, and an increase in the number and balloon-like swelling of the mitochondria at 72 h after the As2O3 was added. Apoptosis of the annexin-V-positive cell proportion in the neuroblastoma cell lines was increased with increasing the exposure time and the concentration of As2O3, just like the HL-60 cells. Bcl-2 downregulation and PARP degradation were also noted all the cell lines, but these changes were not statistically significant among the 3 cell lines. Taken together, these results indicate that As2O3 is an excellent candidate as a therapeutic agent for the treatment of neuroblastoma. PMID:16166054

Ryu, Kyung-Ha; Woo, So-Youn; Lee, Mi-Young; Jung, Yun-Jae; Yoo, Eun-Sun; Seoh, Ju-Young; Kie, Jeong-Hae; Shin, Hee-Young; Ahn, Hyo-Seop

2005-01-01

267

The effect of brown spider venom on endothelial cell morphology and adhesive structures.  

PubMed

Spiders of the Loxosceles genus have been responsible for severe clinical cases of envenomation worldwide. Accidents involving brown spiders can cause dermonecrotic injury, hemorrhage, hemolysis, platelet aggregation and renal failure. Histological findings of animals treated by venom have shown subendothelial blebs, vacuoles and endothelial cell membrane degeneration of blood vessel walls, as well as fibrin and thrombus formation. The mechanisms by which the venom causes these disorders are poorly understood. In this work, with an endothelial cell line derived from rabbit aorta, we were able to demonstrate that venom binds to the cell surface and the extracellular matrix. Moreover, we observed that the venom also induced morphological alterations, such as cell retraction, homophilic disadhesion and an increasing in filopodia projections. We also demonstrated that toxins present in the venom disorganized focal adhesion points and actin microfilaments of endothelial cells. Nevertheless, endothelial cell viability showed no alterations compared to controls. Additionally, venom treatment changed the fibronectin matrix profile synthesized by these cells as well as cell adhesion to fibronectin. These results suggest that the deleterious effects of venom on blood vessel walls could be a consequence of the direct effect on the endothelial cell surface and adhesive structures involved in blood vessel stability. These effects indirectly lead to leukocyte and platelet activation, disseminated intravascular coagulation and an increase in vessel permeability. PMID:16737725

Paludo, Katia Sabrina; Gremski, Luiza Helena; Veiga, Silvio Sanches; Chaim, Olga Meiri; Gremski, Waldemiro; de Freitas Buchi, Dorly; Nader, Helena Bonciani; Dietrich, Carl Peter; Franco, Célia Regina Cavichiolo

2006-06-15

268

Inflectional Morphology in Cri du Chat Syndrome--A Case Study  

ERIC Educational Resources Information Center

This study examined morphological skills in a girl with cri du chat syndrome, addressing three questions: (1) To what extent does the subject inflect words? (2) To what extent are words inflected correctly? (3) To what extent do the inflected words reflect productive morphological rules, and to what extent can they be considered to be…

Kristoffersen, Kristian Emil

2012-01-01

269

The Relation between Morphological Awareness and Reading and Spelling in Greek: A Longitudinal Study  

ERIC Educational Resources Information Center

The aim of this longitudinal study is to examine the contribution of morphological awareness to the prediction of reading and spelling in Greek. The target group (N = 404) consisted of children, aged 6-9 years at the start of the project, who learn literacy in Cyprus. Because there are no standardized measures of morphological awareness for Greek…

Pittas, Evdokia; Nunes, Terezinha

2014-01-01

270

Morphological and ultrastructural studies of some acritarchs from the Lower Cambrian Lükati Formation, Estonia  

Microsoft Academic Search

Six acritarch species from the Lükati Formation were studied using a combination of techniques, including transmitted light, scanning electron (SEM) and transmission electron (TEM) microscopy. New details of wall ultrastructure, surface microsculpture and internal morphology of the vesicle and processes significantly add to the previously known morphological features and increase the understanding of the form-genera Archaeodiscina, Globosphaeridium, Comasphaeridium, Skiagia, Tasmanites

Nina M. Talyzina; Magorzata Moczydowska

2000-01-01

271

Study of craniofacial morphology and skeletal maturation in juvenile diabetics (Type I)  

Microsoft Academic Search

The aims of this study were to examine the craniofacial morphology of patients with juvenile diabetes, to investigate the effects of juvenile diabetes on general growth and skeletal maturation, and to analyze the pattern of association between craniofacial morphology and skeletal maturation in these patients. The sample consisted of 20 male patients with juvenile diabetes whose ages ranged from 14

Tarek El-Bialy; Samir F. Aboul-Azm; Medhat El-Sakhawy

2000-01-01

272

In vitro effects of Sutherlandia frutescens water extracts on cell numbers, morphology, cell cycle progression and cell death in a tumorigenic and a non-tumorigenic epithelial breast cell line.  

PubMed

Sutherlandia frutescens is a South African herb traditionally used for internal cancers, diabetes, a variety of inflammatory conditions and recently to improve the overall health in cancer and HIV/AIDS patients. The in vitro effects of S. frutescens extracts were evaluated on cell numbers, morphology, cell cycle progression and cell death. Dose-dependent studies (2-10 mg/ml) revealed a decrease in malignant cell numbers when compared to their controls. S. frutescens extracts (10 mg/ml) decreased cell growth in a statistically significantly manner to 26% and 49% (P<0.001) in human breast adenocarcinoma (MCF-7) and human non-tumorigenic epithelial mammary gland cells (MCF-12A) respectively after 72 h of exposure. Cell density was significantly compromised and hypercondensed chromatin, cytoplasmic shrinking, membrane blebbing and apoptotic bodies were more pronounced in the MCF-7 cell line. Both S. frutescens-treated cell lines exhibited and increased tendency for acridine orange staining, suggesting increased lysosomal and/or autophagy activity. Flow cytometry showed an increase in the sub G(1) apoptotic fraction and an S phase arrest in both the 5 mg/ml and 10 mg/ml S. frutescens-treated cells. S. frutescens induced an increase in apoptosis in both cell lines as detected by Annexin V and propidium iodide flow cytometric measurement. At 10 mg/ml, late stages of apoptosis were more prominent in MCF-7 S. frutescens-treated cells when compared to the MCF-12A cells. Transmission electron microscopy revealed hallmarks of increased vacuolarization and hypercondensed chromatin, suggesting autophagic and apoptotic processes. The preliminary study demonstrates that S. frutescens water extracts exert a differential action mechanism in non-tumorigenic MCF-12A cells when compared to tumorigenic MCF-7 cells, warranting future studies on this multi-purpose medicinal plant in southern Africa. PMID:19527821

Stander, Andre; Marais, Sumari; Stivaktas, Voula; Vorster, Christiaan; Albrecht, Carl; Lottering, Mona-Liza; Joubert, Annie M

2009-07-01

273

Heterogeneity in Mitochondrial Morphology and Membrane Potential Is Independent of the Nuclear Division Cycle in Multinucleate Fungal Cells  

PubMed Central

In the multinucleate filamentous fungus Ashbya gossypii, nuclei divide asynchronously in a common cytoplasm. We hypothesize that the division cycle machinery has a limited zone of influence in the cytoplasm to promote nuclear autonomy. Mitochondria in cultured mammalian cells undergo cell cycle-specific changes in morphology and membrane potential and therefore can serve as a reporter of the cell cycle state of the cytoplasm. To evaluate if the cell cycle state of nuclei in A. gossypii can influence the adjacent cytoplasm, we tested whether local mitochondrial morphology and membrane potential in A. gossypii are associated with the division state of a nearby nucleus. We found that mitochondria exhibit substantial heterogeneity in both morphology and membrane potential within a single multinucleated cell. Notably, differences in mitochondrial morphology or potential are not associated with a specific nuclear division state. Heterokaryon mutants with a mixture of nuclei with deletions of and wild type for the mitochondrial fusion/fission genes DNM1 and FZO1 exhibit altered mitochondrial morphology and severe growth and sporulation defects. This dominant effect suggests that the gene products may be required locally near their expression site rather than diffusing widely in the cell. Our results demonstrate that mitochondrial dynamics are essential in these large syncytial cells, yet morphology and membrane potential are independent of nuclear cycle state. PMID:22267774

Gerstenberger, John P.; Occhipinti, Patricia

2012-01-01

274

Expression of orphan G-protein coupled receptor GPR174 in CHO cells induced morphological changes and proliferation delay via increasing intracellular cAMP  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Expression of GPR174 in CHO cells induces morphological changes and proliferation delay. Black-Right-Pointing-Pointer These are due to increase in intracellular cAMP concentration. Black-Right-Pointing-Pointer Lysophosphatidylserine was identified to stimulate GPR174 leading to activate ACase. Black-Right-Pointing-Pointer The potencies of fatty acid moiety on LysoPS were oleoyl Greater-Than-Or-Slanted-Equal-To stearoyl > palmitoyl. Black-Right-Pointing-Pointer We propose that GPR174 is a lysophosphatidylserine receptor. -- Abstract: We established cell lines that stably express orphan GPCR GPR174 using CHO cells, and studied physiological and pharmacological features of the receptor. GPR174-expressing cells showed cell-cell adhesion with localization of actin filaments to cell membrane, and revealed significant delay of cell proliferation. Since the morphological changes of GPR174-cells were very similar to mock CHO cells treated with cholera toxin, we measured the concentration of intracellular cAMP. The results showed the concentration was significantly elevated in GPR174-cells. By measuring intracellular cAMP concentration in GPR174-cells, we screened lipids and nucleotides to identify ligands for GPR174. We found that lysophosphatidylserine (LysoPS) stimulated increase in intracellular cAMP in a dose-dependent manner. Moreover, phosphorylation of Erk was elevated by LysoPS in GPR174 cells. These LysoPS responses were inhibited by NF449, an inhibitor of G{alpha}{sub s} protein. These results suggested that GPR174 was a putative LysoPS receptor conjugating with G{alpha}{sub s}, and its expression induced morphological changes in CHO cells by constitutively activating adenylyl cycles accompanied with cell conjunctions and delay of proliferation.

Sugita, Kazuya; Yamamura, Chiaki; Tabata, Ken-ichi [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan)] [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); Fujita, Norihisa, E-mail: nori@ph.ritsumei.ac.jp [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan) [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); School of Pharmacy, Ristumeikan University, Kusatsu, Shiga 525-8577 (Japan)

2013-01-04

275

Parallel geometric classification of stem cells by their three-dimensional morphology  

NASA Astrophysics Data System (ADS)

There is a need for tools to classify cells based on their three-dimensional (3D) shape. Cells exist in vivo in 3D, cells are frequently cultured within 3D scaffolds in vitro and 3D scaffolds are used for cell delivery in tissue engineering therapies. Recent work indicates that the physical structure of a tissue engineering scaffold can direct stem cell function by driving stem cells into morphologies that induce their differentiation. Thus, we have developed a rapid method for classifying cells based on their 3D shape. First, random lines are intersected with 3D Z-stacks of confocal images of stem cells. The intersection lengths are stored in histograms, which are then used to train a support vector machine (SVM) learning algorithm to distinguish between stem cells cultured on differentiation-inducing 3D scaffolds and those cultured on non-differentiating flat substrates. The trained SVM is able to properly classify the ‘new’ query cells over 80% of the time. The algorithm is easily parallelizable and we demonstrate its implementation on a commodity graphics processing unit (GPU). Use of a GPU to run the algorithm increases throughput by over 100-fold as compared to use of a CPU. The algorithm is also progressive, providing an approximate answer quickly and refining the answer over time. This allows further increase in the throughput of the algorithm by allowing the SVM classification scheme to terminate early if it becomes confident enough of the class of the cell being analyzed. These results demonstrate a rapid method for classifying stem cells based on their 3D shape that can be used by tissue engineers for identifying 3D tissue scaffold structures that drive stem cells into shapes that correlate with differentiation.

Juba, Derek; Cardone, Antonio; Yiu Ip, Cheuk; Simon, Carl G., Jr.; Tison, Christopher K.; Kumar, Girish; Brady, Mary; Varshney, Amitabh

2013-01-01

276

[Morphologic changes of red blood cells in various conditions under scanning electron microscope].  

PubMed

To study the changes of RBC in various conditions, blood clots elapsed 6 days in water and air and bloodstains stored in variant time were observed under Scanning Electron Microscope (SEM). The results showed that the morphology of RBC elapsed 6 days in water and air seemed to retain their integrity. They were measured 5, 48-5, 88 microns in diameter, whereas the RBC in the bloodstains stored 14 years were obviously disfigured and some appeared membrane cracking. However, the structure of RBC membrane was well recognized under the SEM. The morphological changes under the SEM and the forensic significance of the RBC were discussed. PMID:10684014

Liao, Z; Chen, G; Mao, Y; Peng, X; Dong, P; Wu, J

1998-06-01

277

Determining the optimum morphology in high-performance polymer-fullerene organic photovoltaic cells  

PubMed Central

The morphology of bulk heterojunction organic photovoltaic cells controls many of the performance characteristics of devices. However, measuring this morphology is challenging because of the small length-scales and low contrast between organic materials. Here we use nanoscale photocurrent mapping, ultrafast fluorescence and exciton diffusion to observe the detailed morphology of a high-performance blend of PTB7:PC71BM. We show that optimized blends consist of elongated fullerene-rich and polymer-rich fibre-like domains, which are 10–50?nm wide and 200–400?nm long. These elongated domains provide a concentration gradient for directional charge diffusion that helps in the extraction of charge pairs with 80% efficiency. In contrast, blends with agglomerated fullerene domains show a much lower efficiency of charge extraction of ~45%, which is attributed to poor electron and hole transport. Our results show that the formation of narrow and elongated domains is desirable for efficient bulk heterojunction solar cells. PMID:24343223

Hedley, Gordon J.; Ward, Alexander J.; Alekseev, Alexander; Howells, Calvyn T.; Martins, Emiliano R.; Serrano, Luis A.; Cooke, Graeme; Ruseckas, Arvydas; Samuel, Ifor D. W.

2013-01-01

278

Primary cutaneous diffuse large B-cell lymphoma (PCDLBCL), leg-type and other: an update on morphology and treatment.  

PubMed

Primary cutaneous B-cell lymphoma (PCBCL) is an heterogeneous group of lymphoproliferative disorders, which account for 25-30% of all primary cutaneous lymphoma and include three main histotypes: 1) primary cutaneous marginal zone B-cell lymphoma (PCMZL); 2) primary cutaneous follicular center cell lymphoma (PCFCL); 3) primary cutaneous diffuse large B-cell lymphoma (DLBCL), leg type (PCDLBCL-LT). PCMZL and PCFCL are indolent lymphomas, with an excellent prognosis despite an high rate of cutaneous recurrences; in contrast, PCDLBCL-LT is clinically more aggressive and usually requires to be treated with multi-agent chemotherapy and anti-CD20 monoclonal antibodies. PCDLBCL-LT histologically consists of large round cells (centroblasts and immunoblasts), is characterized by strong bcl-2 expression, in the absence of t(14;18) translocation, and resembles the activated B-cell type of nodal DLBCL. Recently, the term primary cutaneous DLBCL-other (PCDLBCL-O) has been proposed to include diffuse lymphomas composed of large transformed B-cells that lack the typical features of PCDLBCL-LT and do not conform to the definition of PCFCL. Some clinical studies suggested that such cases have an indolent clinical course and may be treated in a conservative manner; however, data regarding the actual prognosis and clinical behaviour of these peculiar cases are still too limited. The spectrum of primary cutaneous DLBCL also encompasses some rare morphological variants, such as anaplastic or plasmablastic subtypes and T-cell rich B-cell lymphoma, and some recently described, exceedingly rare DLBCL subtypes, such as intravascular large B-cell lymphoma and EBV-associated large B-cell lymphoma of the elderly, which often present in the skin. PMID:23149705

Paulli, M; Lucioni, M; Maffi, A; Croci, G A; Nicola, M; Berti, E

2012-12-01

279

Developmental alterations of the C. elegans male anal depressor morphology and function require sex-specific cell autonomous and cell non-autonomous interactions.  

PubMed

We studied the Caenorhabditis elegans anal depressor development in larval males and hermaphrodites to address how a differentiated cell sex-specifically changes its morphology prior to adulthood. In both sexes, the larval anal depressor muscle is used for defecation behavior. However in the adult males, the muscle's sarcomere is reorganized to facilitate copulation. To address when the changes occur in the anal depressor, we used YFP:actin to monitor, and mutant analysis, laser-ablation and transgenic feminization to perturb the cell's morphological dynamics. In L1 and L2 stage larva, the muscle of both sexes has similar sarcomere morphology, but the hermaphrodite sex-determination system promotes more growth. The male anal depressor begins to change in the L3 stage, first by retracting its muscle arm from the neurons of the defecation circuit. Then the muscle's ventral region develops a slit that demarcates an anterior and posterior domain. This demarcation is not dependent on the anal depressor's intrinsic genetic sex, but is influenced by extrinsic interactions with the developing male sex muscles. However, subsequent changes are dependent on the cell's sex. In the L4 stage, the anterior domain first disassembles the dorsal-ventral sarcomere region and develops filopodia that elongates anteriorly towards the spicule muscles. Later, the posterior domain dissembles the remnants of its sarcomere, but still retains a vestigial attachment to the ventral body wall. Finally, the anterior domain attaches to the sex muscles, and then reassembles an anterior-posteriorly oriented sarcomere. Our work identifies key steps in the dimorphic re-sculpting of the anal depressor that are regulated by genetic sex and by cell-cell signaling. PMID:25498482

Chen, Xin; René García, L

2015-02-01

280

Influence of charge carrier mobility and morphology on solar cell parameters in devices of mono- and bis-fullerene adducts.  

PubMed

Herein, we analyze charge carrier mobility and morphology of the active blend layer in thin film organic solar cells and correlate them with device parameters. A low band gap donor-acceptor copolymer in combination with phenyl-C61-butyric acid methyl ester (PCBM) or two bis-adduct fullerenes, bis-PCBM and bis-o-quino-dimethane C60 (bis-oQDMC), is investigated. We study the charge transport of polymer:fullerene blends in hole- and electron-only devices using the space-charge limited current method. Lower electron mobilities are observed in both bis-adduct fullerene blends. Hole mobility, however, is decreased only in the blend containing bis-oQDMC. Both bis-adduct fullerene blends show very high open circuit voltage in solar cell devices, but poor photocurrent compared to the standard PCBM blend for an active layer thickness of 200 nm. Therefore, a higher short circuit current is feasible for the polymer:bis-PCBM blend by reducing the active layer thickness in order to compensate for the low electron mobility, which results in a PCE of 4.3%. For the polymer:bis-oQDMC blend, no such improvement is achieved due to an unfavorable morphology in this particular blend system. The results are supported by external quantum efficiency measurements, atomic force microscopy, transmission electron microscopy and UV/vis spectroscopy. Based on these results, the investigations presented herein give a more scientific basis for the optimization of solar cells. PMID:24196215

Muth, Mathis-Andreas; Mitchell, William; Tierney, Steven; Lada, Thomas A; Xue, Xiang; Richter, Henning; Carrasco-Orozco, Miguel; Thelakkat, Mukundan

2013-12-01

281

NADPH-diaphorase activity in area 17 of the squirrel monkey visual cortex: neuropil pattern, cell morphology and laminar distribution.  

PubMed

We studied the distribution of NADPH-diaphorase activity in the visual cortex of normal adult New World monkeys (Saimiri sciureus) using the malic enzyme "indirect" method. NADPH-diaphorase neuropil activity had a heterogeneous distribution. In coronal sections, it had a clear laminar pattern that was coincident with Nissl-stained layers. In tangential sections, we observed blobs in supragranular layers of V1 and stripes throughout the entire V2. We quantified and compared the tangential distribution of NADPH-diaphorase and cytochrome oxidase blobs in adjacent sections of the supragranular layers of V1. Although their spatial distributions were rather similar, the two enzymes did not always overlap. The histochemical reaction also revealed two different types of stained cells: a slightly stained subpopulation and a subgroup of deeply stained neurons resembling a Golgi impregnation. These neurons were sparsely spined non-pyramidal cells. Their dendritic arbors were very well stained but their axons were not always evident. In the gray matter, heavily stained neurons showed different dendritic arbor morphologies. However, most of the strongly reactive cells lay in the subjacent white matter, where they presented a more homogenous morphology. Our results demonstrate that the pattern of NADPH-diaphorase activity is similar to that previously described in Old World monkeys. PMID:9458970

Franca, J G; do-Nascimento, J L; Picanço-Diniz, C W; Quaresma, J A; Silva, A L

1997-09-01

282

Mitochondrial morphology, topology, and membrane interactions in skeletal muscle: a quantitative three-dimensional electron microscopy study.  

PubMed

Dynamic remodeling of mitochondrial morphology through membrane dynamics are linked to changes in mitochondrial and cellular function. Although mitochondrial membrane fusion/fission events are frequent in cell culture models, whether mitochondrial membranes dynamically interact in postmitotic muscle fibers in vivo remains unclear. Furthermore, a quantitative assessment of mitochondrial morphology in intact muscle is lacking. Here, using electron microscopy (EM), we provide evidence of interacting membranes from adjacent mitochondria in intact mouse skeletal muscle. Electron-dense mitochondrial contact sites consistent with events of outer mitochondrial membrane tethering are also described. These data suggest that mitochondrial membranes interact in vivo among mitochondria, possibly to induce morphology transitions, for kiss-and-run behavior, or other processes involving contact between mitochondrial membranes. Furthermore, a combination of freeze-fracture scanning EM and transmission EM in orthogonal planes was used to characterize and quantify mitochondrial morphology. Two subpopulations of mitochondria were studied: subsarcolemmal (SS) and intermyofibrillar (IMF), which exhibited significant differences in morphological descriptors, including form factor (means ± SD for SS: 1.41 ± 0.45 vs. IMF: 2.89 ± 1.76, P < 0.01) and aspect ratio (1.97 ± 0.83 vs. 3.63 ± 2.13, P < 0.01) and circularity (0.75 ± 0.16 vs. 0.45 ± 0.22, P < 0.01) but not size (0.28 ± 0.31 vs. 0.27 ± 0.20 ?m(2)). Frequency distributions for mitochondrial size and morphological parameters were highly skewed, suggesting the presence of mechanisms to influence mitochondrial size and shape. In addition, physical continuities between SS and IMF mitochondria indicated mixing of both subpopulations. These data provide evidence that mitochondrial membranes interact in vivo in mouse skeletal muscle and that factors may be involved in regulating skeletal muscle mitochondrial morphology. PMID:23104694

Picard, Martin; White, Kathryn; Turnbull, Douglass M

2013-01-15

283

PHYSIOLOGICAL AND MORPHOLOGICAL CHANGES IN IMMOBILIZED L. PLANTARUM NCIM 2084 CELLS DURING REPEATED BATCH FERMENTATION FOR PRODUCTION OF LACTIC ACID  

Microsoft Academic Search

L. Plantarum NCIM 2084 cells are homofermentative, essentially producing lactic acid as the main end product of glucose fermentation. Prolonged use through repeated batch fermentation with the cells of L. plantarum immobilized on chitosan treated polypropylene matrix showed a shift in the metabolic pathway from the homofermentative to heterofermentative, accompanied by morphological changes in immobilized cells from the normal rod

Sudha Krishnan; Lalitha R. Gowda; M. C. Misra; N. G. Karanth

2001-01-01

284

Striking differences in morphology exist between the red blood cells of mammalian and non-mammalian vertebrates.  

E-print Network

Striking differences in morphology exist between the red blood cells of mammalian and non-mammalian vertebrates. One of the most notable differences is that mammalian red blood cells lose their nuclei before entering the blood, whereas non-mammalian red blood cells remain nucleated throughout their circulatory

Hawai'i at Manoa, University of

285

A biomaterial model of tumor stromal microenvironment promotes mesenchymal morphology but not epithelial to mesenchymal transition in epithelial cells.  

PubMed

The stromal tissue surrounding most carcinomas is comprised of an extracellular matrix densely packed with collagen-I fibers, which are often highly aligned in metastatic disease. Here we developed an in vitro model to test the effect of an aligned fibrous environment on cancer cell morphology and behavior, independent of collagen ligand presentation. We grew cells on a biomimetic surface of aligned electrospun poly-l-lactic acid (PLLA) fibers and then examined the effect of this environment on growth rate, morphology, cytoskeletal organization, biochemical and genetic markers of epithelial to mesenchymal transition (EMT), cell surface adhesion, and cell migration. We grew a phenotypically normal breast epithelial cell line (MCF10A) and an invasive breast cancer cell line (MDA-MB-231) on three different substrates: typical flat culture surface (glass or plastic), flat PLLA (glass coated with PLLA) or electrospun PLLA fibers. Cells of both types adopted a more mesenchymal morphology when grown on PLLA fibers, and this effect was exaggerated in the more metastatic-like MDA-MB-231 cells. However, neither cell type underwent the changes in gene expression indicative of EMT despite the changes in cell shape, nor did they exhibit the decreased adhesive strength or increased migration typical of metastatic cells. These results suggest that changes in cell morphology alone do not promote a more mesenchymal phenotype and consequently that the aligned fibrous environment surrounding epithelial cancers may not promote EMT solely through topographical cues. PMID:25058401

McLane, Joshua S; Rivet, Christopher J; Gilbert, Ryan J; Ligon, Lee A

2014-11-01

286

Light-emitting dendrimer film morphology: A neutron reflectivity study  

NASA Astrophysics Data System (ADS)

We have used neutron reflectivity (NR) measurements to probe the physical structure of phosphorescent dendrimer films. The dendrimers consisted of fac-tris(2-phenylpyridyl)iridium(III) cores, biphenyl-based dendrons (first or second generation), and perdeuterated 2-ethylhexyloxy surface groups. We found that the shape and hydrodynamic radius of the dendrimer were both important factors in determining the packing density of the dendrimers. "Cone" shaped dendrimers were found to pack more effectively than "spherical" dendrimers even when the latter had a smaller radius. The morphology of the films determined by NR was consistent with the measured photoluminescence and charge transporting properties of the materials.

Vickers, S. V.; Barcena, H.; Knights, K. A.; Thomas, R. K.; Ribierre, J.-C.; Gambino, S.; Samuel, I. D. W.; Burn, P. L.; Fragneto, Giovanna

2010-06-01

287

Epithelial cell morphology and adhesion on diamond films deposited and chemically modified by plasma processes.  

PubMed

The authors show that nanocrystalline diamond (NCD) thin films prepared by microwave plasma enhanced chemical vapor deposition apparatus with a linear antenna delivery system are well compatible with epithelial cells (5637 human bladder carcinoma) and significantly improve the cell adhesion compared to reference glass substrates. This is attributed to better adhesion of adsorbed layers to diamond as observed by atomic force microscopy (AFM) beneath the cells. Moreover, the cell morphology can be adjusted by appropriate surface treatment of diamond by using hydrogen and oxygen plasma. Cell bodies, cytoplasmic rims, and filopodia were characterized by Peakforce AFM. Oxidized NCD films perform better than other substrates under all conditions (96% of cells adhered well). A thin adsorbed layer formed from culture medium and supplemented with fetal bovine serum (FBS) covered the diamond surface and played an important role in the cell adhesion. Nevertheless, 50-100 nm large aggregates formed from the RPMI medium without FBS facilitated cell adhesion also on hydrophobic hydrogenated NCD (increase from 23% to 61%). The authors discuss applicability for biomedical uses. PMID:25280853

Rezek, Bohuslav; Ukraintsev, Egor; Krátká, Marie; Taylor, Andrew; Fendrych, Frantisek; Mandys, Vaclav

2014-09-01

288

Morphology and dynamic scaling analysis of cell colonies with linear growth fronts  

NASA Astrophysics Data System (ADS)

The growth of linear cell colony fronts is investigated from the morphology of cell monolayer colonies, the cell size and shape distribution, the front displacement velocity, and the dynamic scaling analysis of front roughness fluctuations. At the early growth stages, colony patterns consist of rather ordered compact domains of small cells, whereas at advanced stages, an uneven distribution of cells sets in, and some large cells and cells exhibiting large filopodia are produced. Colony front profiles exhibit overhangs and behave as fractals with the dimension DF=1.25±0.05 . The colony fronts shift at 0.22±0.02?mmin-1 average constant linear velocity and their roughness (w) increases with time (t) . Dynamic scaling analysis of experimental and overhang-corrected growth profile data shows that w versus system width l log-log plots collapse to a single curve when l exceeds a certain threshold value lo , a width corresponding to the average diameter of few cells. Then, the influence of overhangs on the roughness dynamics becomes negligible, and a growth exponent ?=0.33±0.02 is derived. From the structure factor analysis of overhang-corrected profiles, a global roughness exponent ?s=0.50±0.05 is obtained. For l>200?m , this set of exponents fulfills the Family-Vicsek relationship. It is consistent with the predictions of the continuous Kardar-Parisi-Zhang model.

Huergo, M. A. C.; Pasquale, M. A.; Bolzán, A. E.; Arvia, A. J.; González, P. H.

2010-09-01

289

A morphological study of the enteric mucosal epithelium in the streptozotocin-diabetic mouse.  

PubMed

In the acutely diabetic rat, the polyphagia-induced increase in the weight of the small intestine is associated with reported increases in mucosal mass. Whereas, some of the individual mucosal components in the rat have been studied, comparable information for the acutely streptozotocin-diabetic mouse is lacking. A detailed morphological comparison of the epithelium of the small intestinal mucosa in control and untreated streptozotocin-diabetic mice was therefore undertaken. Samples from three small intestinal sites were examined by light and scanning electron microscopy and quantitative data obtained from histological sections. Although the morphological appearance of the small intestine in acutely diabetic mice was similar in many respects to literature accounts for the diabetic rat, infestation with filamentous microorganisms was present in the jejunum and ileum. The quantitative data showed that these sites also contained distorted villi, fewer crypt profiles, more goblet and Paneth cell profiles and a smaller epithelial volume in comparison to controls. These findings may represent differences between the rat and mouse models of streptozotocin-induced diabetes mellitus. PMID:9365232

Ettarh, R R; Carr, K E

1997-01-01

290

Structural and surface morphological study of Ni doped ZnS nanoparticles  

NASA Astrophysics Data System (ADS)

Samples of Zn1-xNixS (x=0.00, 0.04, 0.08) nanoparticles were synthesized by using the co-precipitation method at room temperature. Structural parameters were investigated by X - ray diffraction (XRD), it reveals that all samples of Ni doped ZnS exhibit the cubic structure with no additional impurity phase. The average crystallite size of all samples is in the range of 2.70 to 2.90 nm. The lattice parameters, X - ray density, volume of unit cell and grain size were calculated using XRD data. It is found that the lattice parameter increases with increasing Ni concentration. Surface morphology of samples was investigated using field emission scanning electron microscopy (FE-SEM). From this study it is concluded that samples exhibit cubic morphology. Chemical compositions of Ni doped and pure ZnS samples were detected using EDAX spectra. It is confirmed from EDAX that Ni substitute into ZnS lattice.

Khawal, H. A.; Dole, B. N.

2014-04-01

291

Morphological changes of BM-N4 cells induced by bombyxin, an insulin-related peptide of Bombyx mori  

Microsoft Academic Search

Bombyxin is a brain secretory peptide of the silkmoth Bombyx mori whose amino acid sequence shows considerable sequence homology with vertebrate insulin-family peptides. We found that a Bombyx cell line, named BM-N4, showed morphological changes when bombyxin was added to the culture medium at doses as low as 10?10 M. Bombyxin-treated cells displayed a series of morphological modifications: 1 to

Minoru Tanaka; Hiroshi Kataoka; Koji Nagata; Hiromichi Nagasawa; Akinori Suzuki

1995-01-01

292

Dynamic changes in brewing yeast cells in culture revealed by statistical analyses of yeast morphological data.  

PubMed

The vitality of brewing yeasts has been used to monitor their physiological state during fermentation. To investigate the fermentation process, we used the image processing software, CalMorph, which generates morphological data on yeast mother cells and bud shape, nuclear shape and location, and actin distribution. We found that 248 parameters changed significantly during fermentation. Successive use of principal component analysis (PCA) revealed several important features of yeast, providing insight into the dynamic changes in the yeast population. First, PCA indicated that much of the observed variability in the experiment was summarized in just two components: a change with a peak and a change over time. Second, PCA indicated the independent and important morphological features responsible for dynamic changes: budding ratio, nucleus position, neck position, and actin organization. Thus, the large amount of data provided by imaging analysis can be used to monitor the fermentation processes involved in beer and bioethanol production. PMID:24012106

Ohnuki, Shinsuke; Enomoto, Kenichi; Yoshimoto, Hiroyuki; Ohya, Yoshikazu

2014-03-01

293

Reprogramming cells to study vacuolar development  

PubMed Central

During vegetative and embryonic developmental transitions, plant cells are massively reorganized to support the activities that will take place during the subsequent developmental phase. Studying cellular and subcellular changes that occur during these short transitional periods can sometimes present challenges, especially when dealing with Arabidopsis thaliana embryo and seed tissues. As a complementary approach, cellular reprogramming can be used as a tool to study these cellular changes in another, more easily accessible, tissue type. To reprogram cells, genetic manipulation of particular regulatory factors that play critical roles in establishing or repressing the seed developmental program can be used to bring about a change of cell fate. During different developmental phases, vacuoles assume different functions and morphologies to respond to the changing needs of the cell. Lytic vacuoles (LVs) and protein storage vacuoles (PSVs) are the two main vacuole types found in flowering plants such as Arabidopsis. Although both are morphologically distinct and carry out unique functions, they also share some similar activities. As the co-existence of the two vacuole types is short-lived in plant cells, how they replace each other has been a long-standing curiosity. To study the LV to PSV transition, LEAFY COTYLEDON2, a key transcriptional regulator of seed development, was overexpressed in vegetative cells to activate the seed developmental program. At the cellular level, Arabidopsis leaf LVs were observed to convert to PSV-like organelles. This presents the opportunity for further research to elucidate the mechanism of LV to PSV transitions. Overall, this example demonstrates the potential usefulness of cellular reprogramming as a method to study cellular processes that occur during developmental transitions. PMID:24348496

Feeney, Mistianne; Frigerio, Lorenzo; Kohalmi, Susanne E.; Cui, Yuhai; Menassa, Rima

2013-01-01

294

Morphologic and immunophenotypic diversity in Ewing family tumors: a study of 66 genetically confirmed cases.  

PubMed

More than 85% of Ewing sarcoma/primitive neuroectodermal tumor (ES/PNET), or "Ewing family of tumors" (EFTs), have the translocation, t (11;22) (q24;q12), with others having variant translocations. Identification of these by cytogenetic and/or molecular genetic techniques is specific for EFT and is increasingly recognized as the "gold standard" for diagnosis. However, these techniques are not universally available. We therefore studied a large group of genetically confirmed EFTs to more completely understand the morphologic and immunophenotypic spectrum of this rare sarcoma. Sixty-six cytogenetically, FISH or RT-PCR proven-EFTs were retrieved. In 56 cases, immunohistochemistry (IHC) was performed for pan-cytokeratins (PanCK), high molecular weight cytokeratins (HMWCK), desmin (DES), CD99, CD117, and FLI1 protein using heat-induced epitope retrieval and the Dako Envision system. The cases arose chiefly in children and young adults (median 18 years; range, 3-65 years) of both sexes (male, 32; female, 31; unknown, 3) in a variety of bone (N = 39) and soft tissue (N = 27) sites. Histologically, 46 cases (73%) showed only typical features of ES, 9 cases (16%) showed features of PNET, 3 cases (5%) showed "adamantinoma-like" features, 3 cases (5%) corresponded to "atypical Ewing sarcoma," 3 cases (5%) showed principally intersecting fascicles of spindled cells, and 2 cases had abundant hyalinized matrix. IHC results were as follows: PanCK (18 of 56, 32%), HMWCK (3 of 55, 5%), DES (1 of 56, 2%), CD99 (52 of 52, 100%), CD117 (13 of 54, 24%), and FLI1 (44 of 47, 94%). HMWCK was expressed only in "adamantinoma-like" EFTs, none of which expressed DES. In conclusion, most, but not all, EFTs can be accurately diagnosed using time-honored morphologic criteria and ancillary immunohistochemistry. However, genetic confirmation remains essential for the diagnosis of unusual morphologic variants of EFT, including "adamantinoma-like," spindled, sclerosing, and clear cell/anaplastic variants. Therefore, to exclude or confirm the diagnosis of Ewing's sarcoma in round cell sarcomas having a variety of patterns but not specifically conforming to a tumor of known lineage (eg, rhabdomyosarcoma), cytogenetics, and/or molecular analysis is required. PMID:16006796

Folpe, Andrew L; Goldblum, John R; Rubin, Brian P; Shehata, Bahig M; Liu, Wendy; Dei Tos, Angelo P; Weiss, Sharon W

2005-08-01

295

Anatomical study of the human omohyoid muscle: regarding intermediate morphologies between normal and anomalous morphologies of the superior belly  

Microsoft Academic Search

Intermediate morphologies between normal and anomalous morphologies of the superior belly of the omohyoid muscle (Om) were\\u000a macroscopically and stereomicroscopically observed in 34 cadavers (24 males and 10 females aged between 51 and 97 years; average\\u000a age 71.0 years) for anatomical practice, which had been preserved in the Department of Morphological Biology, Ohu University\\u000a School of Dentistry. The intermediate morphologies

Reiki Sukekawa; Ichizoh Itoh

2006-01-01

296

A morphological study of the vomeronasal organ and the accessory olfactory bulb in the Korean roe deer, Capreolus pygargus.  

PubMed

The vomeronasal organ (VNO) and accessory olfactory bulb (AOB) of the Korean roe deer (Capreolus pygargus) were studied histologically to evaluate their morphological characteristics. Grossly, the VNO, encased by cartilage, has a paired tubular structure with a caudal blind end and a rostral connection through incisive ducts on the hard palate. In the VNO, the vomeronasal sensory epithelium (VSE) consists of galectin-3-positive supporting cells, protein gene product (PGP) 9.5-positive receptor cells, and basal cells. The vomeronasal respiratory epithelium (VRE) consists of a pseudostratified epithelium. The AOB strata included a vomeronasal nerve layer (VNL), a glomerular layer (GL), a mitral/tufted cell layer, and a granular cell layer. All lectins used in this study, including Bandeiraea simplicifolia agglutinin isolectin B4 (BSI-B4), soybean agglutinin (SBA), Ulex europaeus agglutinin I (UEA-I), and Triticum vulgaris wheat germ agglutinin (WGA), labeled the VSE with varying intensity. In the AOB, both the VNL and the GL reacted with BSI-B4, SBA, and WGA with varying intensity, but not with UEA-I. This is the first morphological study of the VNO and AOB of the Korean roe deer, which are similar to those of goats. PMID:24055195

Park, Changnam; Ahn, Meejung; Lee, Jae-Yuk; Lee, Sang; Yun, Youngmin; Lim, Yoon-Kyu; Taniguchi, Kazumi; Shin, Taekyun

2014-01-01

297

Metre-long cell-laden microfibres exhibit tissue morphologies and functions  

NASA Astrophysics Data System (ADS)

Artificial reconstruction of fibre-shaped cellular constructs could greatly contribute to tissue assembly in vitro. Here we show that, by using a microfluidic device with double-coaxial laminar flow, metre-long core-shell hydrogel microfibres encapsulating ECM proteins and differentiated cells or somatic stem cells can be fabricated, and that the microfibres reconstitute intrinsic morphologies and functions of living tissues. We also show that these functional fibres can be assembled, by weaving and reeling, into macroscopic cellular structures with various spatial patterns. Moreover, fibres encapsulating primary pancreatic islet cells and transplanted through a microcatheter into the subrenal capsular space of diabetic mice normalized blood glucose concentrations for about two weeks. These microfibres may find use as templates for the reconstruction of fibre-shaped functional tissues that mimic muscle fibres, blood vessels or nerve networks in vivo.

Onoe, Hiroaki; Okitsu, Teru; Itou, Akane; Kato-Negishi, Midori; Gojo, Riho; Kiriya, Daisuke; Sato, Koji; Miura, Shigenori; Iwanaga, Shintaroh; Kuribayashi-Shigetomi, Kaori; Matsunaga, Yukiko T.; Shimoyama, Yuto; Takeuchi, Shoji

2013-06-01

298

Improved morphology control using a modified two-step method for efficient perovskite solar cells.  

PubMed

A two-step wet chemical synthesis method for methylammonium lead(II) triiodide (CH3NH3PbI3) perovskite is further developed for the preparation of highly reproducible solar cells, with the following structure: fluorine-doped tin oxide (FTO)/TiO2 (compact)/TiO2 (mesoporous)/CH3NH3PbI3/spiro-OMeTAD/Ag. The morphology of the perovskite layer could be controlled by careful variation of the processing conditions. Specifically, by modifying the drying process and inclusion of a dichloromethane treatment, more uniform films could be prepared, with longer emission lifetime in the perovskite material and longer electron lifetime in solar cell devices, as well as faster electron transport and enhanced charge collection at the selective contacts. Solar cell efficiencies up to 13.5% were obtained. PMID:25317666

Bi, Dongqin; El-Zohry, Ahmed M; Hagfeldt, Anders; Boschloo, Gerrit

2014-11-12

299

Effect of Serum and Insulin Modulation on the Organization and Morphology of Matrix Synthesized by Bovine Corneal Stromal Cells  

PubMed Central

The in vitro production of highly organized collagen fibrils by corneal keratocytes in a three-dimensional scaffold-free culture system presents a unique opportunity for the direct observation of organized matrix formation. The objective of this investigation was to develop such a culture system in a glass substrate (for optical accessibility) and to directly examine the effect of reducing serum and/or increasing insulin on the stratification and secretion of aligned matrix by fourth- to fifth-passage bovine corneal stromal keratocytes. Medium concentrations of 0%, 1%, or 10% fetal bovine serum and 0% or 1% insulin–transferrin–selenium were investigated. High-resolution differential interference contrast microscopy, quick-freeze/deep-etch, and conventional transmission electron microscopy were used to monitor the evolution, morphology, and ultrastructure of the cell–matrix constructs. In a medium containing 1% each of serum and insulin–transferrin–selenium, stromal cells stratified and secreted abundant and locally aligned matrix, generating the thickest cell–matrix constructs (allowing handling with forceps). The results of this study have the potential to significantly advance the field of developmental functional engineering of load-bearing tissues by (i) elucidating cues that modulate in vitro cell secretion of organized matrix and (ii) establishing an optically accessible cell culture system for investigating the mechanism of cell secretion of aligned collagen fibrils. PMID:19480568

Bueno, Ericka M.; Saeidi, Nima; Melotti, Suzanna

2009-01-01

300

Morphologic evidence for differentiation of pinealocytes from photoreceptor cells in the adult noctule bat (Nyctalus noctula, Schreber).  

PubMed

An electron microscopical investigation of the pineal gland of the adult noctule bat revealed the presence of some peculiar ciliary derivatives, similar to the club-shaped outer segment of rudimentary photoreceptor cells in the pineal organ of nonmammalian vertebrates. The pinealocytes of population I can be classified in several morphological types, one of them displaying morphological features resembling those of rudimentary photoreceptor cells. These results reconfirm the concept of the sensory cell line in the vertebrate pineal organ. The question whether the pinealocytes of population II belong to the same sensory cell line is discussed. PMID:884730

Pevet, P; Ariëns Kappers, J; Voűte, A M

1977-07-26

301

[Experimental study on decoctum Agrimonia pilosa Ledeb-induced apoptosis in HL-60 cells in vitro].  

PubMed

In this study, MTT assay, cell morphology and flow cytometry were used to explore Agrimonia pilosa Ledeb on HL-60 cells in vitro. The data suggested that Agrimonia pilosa Ledeb had the effects of growth inhibition in HL-60 cells. After treated with decoctum Agrimonia pilosa Ledeb, cells underwent apoptosis with typical morphological feature. DNA histograms by flow cytometric analysis displayed distinct apoptotic peak. PMID:12575284

Gao, K; Zhou, L; Chen, J; Li, F; Zhang, L

2000-09-01

302

A rapid antimicrobial susceptibility test based on single-cell morphological analysis.  

PubMed

A rapid antibiotic susceptibility test (AST) is desperately needed in clinical settings for fast and appropriate antibiotic administration. Traditional ASTs, which rely on cell culture, are not suitable for urgent cases of bacterial infection and antibiotic resistance owing to their relatively long test times. We describe a novel AST called single-cell morphological analysis (SCMA) that can determine antimicrobial susceptibility by automatically analyzing and categorizing morphological changes in single bacterial cells under various antimicrobial conditions. The SCMA was tested with four Clinical and Laboratory Standards Institute standard bacterial strains and 189 clinical samples, including extended-spectrum ?-lactamase-positive Escherichia coli and Klebsiella pneumoniae, imipenem-resistant Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococci from hospitals. The results were compared with the gold standard broth microdilution test. The SCMA results were obtained in less than 4 hours, with 91.5% categorical agreement and 6.51% minor, 2.56% major, and 1.49% very major discrepancies. Thus, SCMA provides rapid and accurate antimicrobial susceptibility data that satisfy the recommended performance of the U.S. Food and Drug Administration. PMID:25520395

Choi, Jungil; Yoo, Jungheon; Lee, Mincheol; Kim, Eun-Geun; Lee, Ji Soo; Lee, Seungok; Joo, Seik; Song, Sang Hoon; Kim, Eui-Chong; Lee, Jung Chan; Kim, Hee Chan; Jung, Yong-Gyun; Kwon, Sunghoon

2014-12-17

303

Morphological and histological characteristics of mammary dysplasias occurring in cell dissociation-derived murine mammary outgrowths  

SciTech Connect

The morphological and histological characteristics of ductal dysplasias that were observed in mammary outgrowths derived from monodispersed mammary cells of carcinogen-treated mice are described. Mammary outgrowths were derived by injecting either 10(4) or 10(5) enzymatically dissociated mammary cells, obtained from control or carcinogen-treated BALB/c mice, into gland-free mammary fat pads of syngeneic hosts. The mammary dysplasias observed varied considerably in morphological and histological characteristics. The majority of the lesions were ductal in origin and were associated with epithelial hyperplasia which ranged from mild hyperplasia, in which only a few extra layers of epithelium were present, to severe hyperplasia, in which the ducts and end buds were occluded and distended with epithelial cells. In addition, papillary and lobular lesions were observed which were also associated with varying degrees of hyperplasia. The range of mammary dysplasias observed in these outgrowths closely resembles that of lesions associated with the pathogenesis of mammary carcinoma in mice, rats, and humans.

Ethier, S.P.; Adams, L.M.; Ullrich, R.L.

1984-10-01

304

The effect of morphology on spelling and reading accuracy: a study on Italian children  

PubMed Central

In opaque orthographies knowledge of morphological information helps in achieving reading and spelling accuracy. In transparent orthographies with regular print-to-sound correspondences, such as Italian, the mappings of orthography onto phonology and phonology onto orthography are in principle sufficient to read and spell most words. The present study aimed to investigate the role of morphology in the reading and spelling accuracy of Italian children as a function of school experience to determine whether morphological facilitation was present in children learning a transparent orthography. The reading and spelling performances of 15 third-grade and 15 fifth-grade typically developing children were analyzed. Children read aloud and spelled both low-frequency words and pseudowords. Low-frequency words were manipulated for the presence of morphological structure (morphemic words vs. non-derived words). Morphemic words could also vary for the frequency (high vs. low) of roots and suffixes. Pseudo-words were made up of either a real root and a real derivational suffix in a combination that does not exist in the Italian language or had no morphological constituents. Results showed that, in Italian, morphological information is a useful resource for both reading and spelling. Typically developing children benefitted from the presence of morphological structure when they read and spelled pseudowords; however, in processing low-frequency words, morphology facilitated reading but not spelling. These findings are discussed in terms of morpho-lexical access and successful cooperation between lexical and sublexical processes in reading and spelling. PMID:25477855

Angelelli, Paola; Marinelli, Chiara Valeria; Burani, Cristina

2014-01-01

305

Effects of Above-Optimum Growth Temperature and Cell Morphology on Thermotolerance of Listeria monocytogenes Cells Suspended in Bovine Milk  

PubMed Central

The thermotolerances of two different cell forms of Listeria monocytogenes (serotype 4b) grown at 37 and 42.8°C in commercially pasteurized and laboratory-tyndallized whole milk (WM) were investigated. Test strains, after growth at 37 or 42.8°C, were suspended in WM at concentrations of approximately 1.5 × 108 to 3.0 × 108 cells/ml and were then heated at 56, 60, and 63°C for various exposure times. Survival was determined by enumeration on tryptone-soya-yeast extract agar and Listeria selective agar, and D values (decimal reduction times) and Z values (numbers of degrees Celsius required to cause a 10-fold change in the D value) were calculated. Higher average recovery and higher D values (i.e., seen as a 2.5- to 3-fold increase in thermotolerance) were obtained when cells were grown at 42.8°C prior to heat treatment. A relationship was observed between thermotolerance and cell morphology of L. monocytogenes. Atypical Listeria cell types (consisting predominantly of long cell chains measuring up to 60 ?m in length) associated with rough (R) culture variants were shown to be 1.2-fold more thermotolerant than the typical dispersed cell form associated with normal smooth (S) cultures (P ? 0.001). The thermal death-time (TDT) curves of R-cell forms contained a tail section in addition to the shoulder section characteristic of TDT curves of normal single to paired cells (i.e., S form). The factors shown to influence the thermoresistance of suspended Listeria cells (P ? 0.001) were as follows: growth and heating temperatures, type of plating medium, recovery method, and cell morphology. Regression analysis of nonlinear data can underestimate survival of L. monocytogenes; the end point recovery method was shown to be a better method for determining thermotolerance because it takes both shoulders and tails into consideration. Despite their enhanced heat resistance, atypical R-cell forms of L. monocytogenes were unable to survive the low-temperature, long-time pasteurization process when freely suspended and heated in WM. PMID:9603815

Rowan, Neil J.; Anderson, John G.

1998-01-01

306

Morphological studies of human arteriovenous malformations. Effects of isobutyl 2-cyanoacrylate embolization.  

PubMed

Ten patients with symptomatic arteriovenous malformations (AVM's) underwent embolization with isobutyl 2-cyanoacrylate (Bucrylate) delivered via a mini-balloon catheter according to the protocol of George and Pevsner. These patients underwent surgical removal of their embolized AVM, and surgical specimens were evaluated by light and scanning electron microscopy. Ten other patients with AVM's underwent surgical resection without prior embolization, and these surgical specimens were evaluated in a similar manner. Results from this study indicate that Bucrylate incites an inflammatory response characterized by foreign-body giant cells. This reaction was present as early as 3 weeks after embolization and persisted in specimens resected almost 1 year after the last embolization. No such reaction was observed in unembolized AVM's. Both light and scanning electron microscopy demonstrated a lattice structure of the Bucrylate embolus within the AVM vessels. These studies also demonstrated micro-channels within the Bucrylate embolus and the presence of what appears to be normal red blood cells within the latticework of the embolus. Vascular endothelium not in direct contact with the Bucrylate embolus retains a normal morphology as revealed by scanning electron microscopy. PMID:4020470

Klara, P M; George, E D; McDonnell, D E; Pevsner, P H

1985-09-01

307

Micrometer scale spacings between fibronectin nanodots regulate cell morphology and focal adhesions  

NASA Astrophysics Data System (ADS)

Cell adhesion to extracellular matrix is an important process for both health and disease states. Surface protein patterns that are topographically flat, and do not introduce other chemical, topographical or rigidity related functionality and, more importantly, that mimic the organization of the in vivo extracellular matrix are desired. Previous work showed that vinculin and cytoskeletal organization are modulated by size and shape of surface nanopatterns. However, quantitative analysis on cell morphology and focal adhesions as a function of micrometer scale spacings of FN nanopatterns was absent. Here, electron beam lithography was used to pattern fibronectin nanodots with micrometer scale spacings on a K-casein background on indium tin oxide coated glass which, unlike silicon, is transparent and thus suitable for many light microscopy techniques. Exposure times were significantly reduced using the line exposure mode with micrometer scale step sizes. Micrometer scale spacings of 2, 4 and 8 ?m between fibronectin nanodots proved to modulate cell adhesion through modification of cell area, focal adhesion number, size and circularity. Overall, cell behavior was shown to shift at the apparent threshold of 4 ?m spacing. The findings presented here offer exciting new opportunities for cell biology research.

Horzum, Utku; Ozdil, Berrin; Pesen-Okvur, Devrim

2014-04-01

308

Molecular weight dependence of the morphology in P3HT:PCBM solar cells.  

PubMed

In polymer-based photovoltaic devices, optimizing and controlling the active layer morphology is important to enhancing the device efficiency. Using poly(3-hexylthiophene) (P3HT) with well-defined molecular weights (MWs), synthesized by the Grignard metathesis (GRIM) method, we show that the morphology of the photovoltaic active layer and the absorption and crystal structure of P3HT are dependent on the MW. Differential scanning calorimetry showed that the crystallinity of P3HT reached a maximum for intermediate MWs. Grazing-incidence wide-angle X-ray diffraction showed that the spacing of the (100) planes of P3HT increased with increasing MW, while the crystal size decreased. Nonlinear crystal lattice expansions were found for both the (100) and (020) lattice planes, with an unusual ?-?-stacking enhancement observed between 50 and 100 °C. The melting point depression for P3HT, when mixed with [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), and, hence, the Flory-Huggins interaction parameter depended on the MW. PCBM was found to perturb the ordering of P3HT chains. In photovoltaic devices, P3HT with a MW of ?20K showed the best device performance. The morphologies of these blends were studied by grazing-incidence small-angle X-ray scattering (GISAXS) and resonant soft X-ray scattering. In GISAXS, we observed that the low-molecular-weight P3HT more readily crystallizes, promoting a phase-separated morphology. PMID:25350382

Liu, Feng; Chen, Dian; Wang, Cheng; Luo, Kaiyuan; Gu, Weiyin; Briseno, Alejandro L; Hsu, Julia W P; Russell, Thomas P

2014-11-26

309

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

PubMed Central

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

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

2014-01-01

310

Effects of spaceflight in the adductor longus muscle of rats flown in the Soviet Biosatellite COSMOS 2044. A study employing neural cell adhesion molecule (N-CAM) immunocytochemistry and conventional morphological techniques (light and electron microscopy)  

NASA Technical Reports Server (NTRS)

The effects of spaceflight upon the "slow" muscle adductor longus were examined in rats flown in the Soviet Biosatellite COSMOS 2044. The techniques employed included standard methods for light microscopy, neural cell adhesion molecule (N-CAM) immunocytochemistry and electron microscopy. Light microscopic observations revealed myofiber atrophy and segmental necrosis accompanied by cellular infiltrates composed of macrophages, leukocytes and mononuclear cells. Neural cell adhesion molecule immunoreactivity (N-CAM-IR) was seen on the myofiber surface and in regenerating myofibers. Ultrastructural alterations included Z band streaming, disorganization of myofibrillar architecture, sarcoplasmic degradation, extensive segmental necrosis with apparent preservation of the basement membrane, degenerative phenomena of the capillary endothelium and cellular invasion of necrotic areas. Regenerating myofibers were identified by the presence of increased amounts of ribosomal aggregates and chains of polyribosomes associated with myofilaments. The principal electron microscopic changes of the neuromuscular junctions showed axon terminals with a decrease or absence of synaptic vesicles replaced by microtubules and neurofilaments, degeneration of axon terminals, vacant axonal spaces and changes suggestive of axonal sprouting. The present observations suggest that alterations such as myofibrillar disruption and necrosis, muscle regeneration and denervation and synaptic remodeling at the level of the neuromuscular junction may take place during spaceflight.

D'Amelio, F.; Daunton, N. G.

1992-01-01

311

Experiment K-7-28: Lung Morphology Study  

NASA Technical Reports Server (NTRS)

There are no previous studies investigating the effect of microgravity exposure during spaceflight on lung tissue. We examined the ultrastructure of the left lungs of 5 Czechoslovakian Wistar rats flown on the 13 day, 19+ hr. Cosmos 2044 mission, and compared them to 5 vivarium and 5 synchronous controls at 1-g conditions, and 5 rats exposed to 14 days of tail-suspension. Within 10 minutes of sacrifice by decapitation, the lungs were removed and immersed in 3% glutaraldehyde in 0.1M phosphate buffer (total osmolarity of the fixative: 560 mOsm; pH = 7.4). The tissue stored at 5 C was transported to our laboratory where it was processed for light and electron microscopy. No significant perivascular cuffing caused by interstitial edema was present in the tissue samples. Some of the flight, tail-suspended, and synchronous control rats showed alveolar edema, while vivarium controls did not. The pulmonary capillaries appeared to be more congested in the flight animals than in the other groups. This could be related to the increased hematocrit due to the microgravity exposure. In all 5 flight, 4 tail-suspended, and 3 synchronous rats, red blood cells (RBC) were present in the alveolar spaces. The RBC were either suspended free in the alveoli or observed lining the alveolar wall. The frequency of RBC lining the alveolar walls appeared greater in the dorsal (gravity non-dependent) than in ventral (gravity dependent) regions of the lung in these three animal groups. In 3 of the vivarium controls, a few RBC were found in the alveolar spaces. Intra-capillary fluid-filled vesicles were observed in the flight, tail-suspended and synchronous animals, but not in the vivarium controls. The formation of intra-capillary fluid-filled vesicles has been previously associated with pulmonary hypertension induced by high altitude exposure and mitral stenosis. In conclusion, pulmonary hemorrhage and alveolar edema of unknown origin occurred to a greater extent in the flight, tail-suspended, and synchronous control animals, and in the dorsal regions of the lung when compared to the vivarium controls. The etiology of these changes, which are possibly due to an increase in pulmonary vascular pressure, requires further investigation.

West, J. B.; Elliott, A. R.; Mathieu-Costello, O.; Kaplansky, A. S.

1994-01-01

312

T-cell acute lymphoid leukemia resembling Burkitt leukemia cell morphology: A case report  

PubMed Central

Biphenotypic acute leukemia (BAL) is an uncommon type of cancer, which accounts for <5% of all adult ALs. Based upon a previously described scoring system, the European Group for the Immunological Classification of Leukemias (EGIL) proposed a set of diagnostic criteria for BAL. This scoring system is based upon the number and degree of specificity of several markers for myeloid or T/B-lymphoid blasts. The present study describes a case of T-cell acute lymphoblastic leukemia (T-ALL) with Burkitt-like cytology, which according to the French-American-British classification, corresponded to a diagnosis of Burkitt type L3 ALL. Flow cytometry analysis demonstrated that the blasts were positive for T-lymphoid markers, cytoplasmic cluster of differentiation (CD)3, CD7 and CD56, and myeloid markers, CD13, CD33 and CD15. At first, a diagnosis of BAL was suggested by the EGIL score, however, according to the 2008 World Health Organization criteria, a case of T-ALL with aberrant myeloid markers was established. The study also reviewed the literature and discussed the limitations of the EGIL scoring system in clinical decision making, to aid in the selection of an appropriate therapeutic regimen.

YUE, QINGFANG; LIU, XINYUE; CHEN, LEI; LIU, ZHONGPING; CHEN, WANXIN

2015-01-01

313

Influence of PH3 exposure on silicon substrate morphology in the MOVPE growth of III-V on silicon multijunction solar cells  

NASA Astrophysics Data System (ADS)

Dual-junction solar cells formed by a GaAsP or GaInP top cell and a silicon bottom cell seem to be attractive candidates to materialize the long sought-for integration of III-V materials on silicon for photovoltaic applications. One of the first issues to be considered in the development of this structure will be the strategy to create the silicon emitter of the bottom subcell. In this study, we explore the possibility of forming the silicon emitter by phosphorus diffusion (i.e. exposing the wafer to PH3 in a MOVPE reactor) and still obtain good surface morphologies to achieve a successful III-V heteroepitaxy as occurs in conventional III-V on germanium solar cell technology. Consequently, we explore the parameter space (PH3 partial pressure, time and temperature) that is needed to create optimized emitter designs and assess the impact of such treatments on surface morphology using atomic force microscopy. Although a strong degradation of surface morphology caused by prolonged exposure of silicon to PH3 is corroborated, it is also shown that subsequent anneals under H2 can recover silicon surface morphology and minimize its RMS roughness and the presence of pits and spikes.

García-Tabarés, E.; García, I.; Martín, D.; Rey-Stolle, I.

2013-11-01

314

Black silicon SERS substrate: effect of surface morphology on SERS detection and application of single algal cell analysis.  

PubMed

In this study, we have investigated the effect of the surface morphology of the black silicon substrate on surface enhanced Raman spectroscopy (SERS) and explored its application of single algal cell detection. By adjusting the O2 and SF6 flow rates in the cryogenic plasma etching process, different surface morphologies of the black silicon substrate was produced without performing the lithographic process. It was found the Raman signals were better enhanced as the tip density of the black silicon substrate increased. In addition, as the thickness of the deposited gold layer increased, the SERS effect increased as well, which could be owing to the generation of more hot spots by bridging individual silicon tips through deposition of gold layer. For the black silicon substrate with tip density of 30 tips/?m(2) and covered by 400 nm deposited gold layer, the detection limit of 10 fM R6G solution concentration with uniform SERS effect across the substrate was achieved. Furthermore, detection of individual algal cell (Chlorella vulgaris) was performed at the SERS substrate as fabricated and the Raman signals of carotenoid and lipid were substantially enhanced. PMID:24121206

Deng, Yu-Luen; Juang, Yi-Je

2014-03-15

315

Detailed morphological characterisation of Hendra virus infection of different cell types using super-resolution and conventional imaging.  

PubMed

BackgroundHendra virus (HeV) is a pleomorphic virus belonging to the Paramyxovirus family. Our long-term aim is to understand the process of assembly of HeV virions. As a first step, we sought to determine the most appropriate cell culture system with which to study this process, and then to use this model to define the morphology of the virus and identify the site of assembly by imaging key virus encoded proteins in infected cells.MethodsA range of primary cells and immortalised cell lines were infected with HeV, fixed at various time points post-infection, labelled for HeV proteins and imaged by confocal, super-resolution and transmission electron microscopy.ResultsSignificant differences were noted in viral protein distribution depending on the infected cell type. At 8 hpi HeV G protein was detected in the endoplasmic reticulum and M protein was seen predominantly in the nucleus in all cells tested. At 18 hpi, HeV-infected Vero cells showed M and G proteins throughout the cell and in transmission electron microscope (TEM) sections, in pleomorphic virus-like structures. In HeV infected MDBK, A549 and HeLa cells, HeV M protein was seen predominantly in the nucleus with G protein at the membrane. In HeV-infected primary bovine and porcine aortic endothelial cells and two bat-derived cell lines, HeV M protein was not seen at such high levels in the nucleus at any time point tested (8,12, 18, 24, 48 hpi) but was observed predominantly at the cell surface in a punctate pattern co-localised with G protein. These HeV M and G positive structures were confirmed as round HeV virions by TEM and super-resolution (SR) microscopy. SR imaging demonstrated for the first time sub-virion imaging of paramyxovirus proteins and the respective localisation of HeV G, M and N proteins within virions.ConclusionThese findings provide novel insights into the structure of HeV and show that for HeV imaging studies the choice of tissue culture cells may affect the experimental results. The results also indicate that HeV should be considered a predominantly round virus with a mean diameter of approximately 280 nm by TEM and 310 nm by SR imaging. PMID:25428656

Monaghan, Paul; Green, Diane; Pallister, Jackie; Klein, Reuben; White, John; Williams, Catherine; McMillan, Paul; Tilley, Leann; Lampe, Marko; Hawes, Pippa; Wang, Lin-Fa

2014-11-27

316

Automated Cell-by-Cell Tissue Imaging and Single-Cell Analysis for Targeted Morphologies by Laser Ablation  

E-print Network

· Chapter 12 Automated Cell-by-Cell Tissue Imaging and Single-Cell Analysis for Targeted spectrometry (MS) has enabled the direct analysis of single cells and subcellular compartments. Cell-by-cell imaging had been demonstrated using LAESI-MS, where individual cells were manually selected to serve

Vertes, Akos

317

Influence of the morphology of organic heterojunction on the photovoltaic cell performance  

NASA Astrophysics Data System (ADS)

We present a series of organic photovoltaic (PV) cells based on the bulk-distributed heterojunction where ? -conjugated polymer poly[1-(4-trimethylsilylphenyl)-2-phenylvinylene], PSDPhV, acts as the donor upon photoexcitation and the substituted perylene based low-molecular-weight compound: N,N`-di(pent-3-yl)-perylene-3,4:9,10-bis(dicarboximide), DPe-PTCDI, as the acceptor of photogenerated electrons. According to both absorption spectra and AFM images of the thin films spin-coated from solution of DPe-PTCDI and PSDPhV in toluene, the DPe-PTCDI is molecularly dissolved in conjugated polymer matrix. Upon exposition of layers to toluene vapors, microcrystals of DPe-PTCDI are progressively formed. The influence of the morphology of DPe-PTCDI inside the polymer matrix on PV cell performance is investigated. This paper has been presented at “ECHOS06”, Paris, 28 30 juin 2006.

Podhájecká, K.; Pfleger, J.

2006-12-01

318

Pivotal roles for Streptomyces cell surface polymers in morphological differentiation, attachment and mycelial architecture.  

PubMed

Cells that are part of a multicellular structure are typically embedded in an extracellular matrix, which is produced by the community members. These matrices, the composition of which is highly diverse between different species, are typically composed of large amounts of extracellular polymeric substances, including polysaccharides, proteins, and nucleic acids. The functions of all these matrices are diverse: they provide protection, mechanical stability, mediate adhesion to surfaces, regulate motility, and form a cohesive network in which cells are transiently immobilized. In this review we discuss the role of matrix components produced by streptomycetes during growth, development and attachment. Compared to other bacteria it appears that streptomycetes can form morphologically and functionally distinct matrices using a core set of building blocks. PMID:24682579

Petrus, Marloes L C; Claessen, Dennis

2014-07-01

319

Motion of variable-length MreB filaments at the bacterial cell membrane influences cell morphology  

PubMed Central

The maintenance of rod-cell shape in many bacteria depends on actin-like MreB proteins and several membrane proteins that interact with MreB. Using superresolution microscopy, we show that at 50-nm resolution, Bacillus subtilis MreB forms filamentous structures of length up to 3.4 ?m underneath the cell membrane, which run at angles diverging up to 40° relative to the cell circumference. MreB from Escherichia coli forms at least 1.4-?m-long filaments. MreB filaments move along various tracks with a maximal speed of 85 nm/s, and the loss of ATPase activity leads to the formation of extended and static filaments. Suboptimal growth conditions lead to formation of patch-like structures rather than extended filaments. Coexpression of wild-type MreB with MreB mutated in the subunit interface leads to formation of shorter MreB filaments and a strong effect on cell shape, revealing a link between filament length and cell morphology. Thus MreB has an extended-filament architecture with the potential to position membrane proteins over long distances, whose localization in turn may affect the shape of the cell wall. PMID:23783036

Reimold, Christian; Defeu Soufo, Herve Joel; Dempwolff, Felix; Graumann, Peter L.

2013-01-01

320

Pediatric rhabdoid meningioma: a morphological, immunohistochemical, ultrastructural and molecular case study.  

PubMed

Rhabdoid meningioma is an uncommon meningioma variant categorized as WHO grade III. The majority of cases occur in adulthood. Herein, we describe a right fronto-temporal rhabdoid meningioma affecting a 3-year-old boy. The lesion measured approximately 4 cm in diameter and incorporated the ipsilateral middle cerebral artery. Sub-total surgical excision of the mass was performed. Histologically, the tumor was mainly composed of globoid plump cells with inclusion-like eosinophilic cytoplasm, peripheral nuclei, prominent nucleoli and occasional intra-nuclear cytoplasmic pseudo-inclusion. The cells appeared in many areas loosely arranged and focally disclosed a papillary architecture. At immunohistochemistry, the tumor cells were EMA, vimentin, HHF35, PgR, INI-1 and p53 positive. The proliferative index (Mib-1) was 15% in the most positive areas. Ultrastructurally, tumoral cells showed an abundant cytoplasm, which was filled with numerous intermediate filaments. Desmosomal junctions were seen. RT-PCR revealed the presence of NF2 gene expression. Molecular study did not indicate alterations of the INI-1 gene, whereas it showed the presence of Pro72Arg in exon 4 at heterozygous state in the TP53 gene. Morphologic features along with immunohistochemical, ultrastructural and molecular results were consistent with the diagnosis of rhabdoid meningioma. The patient was treated with chemotherapy. The lesion remained stable after 33 months of follow-up. Rhabdoid meningiomas rarely occur in children. Owing to its rarity, each new case should be recorded to produce a better clinical, pathological, molecular, prognostic and therapeutic characterization of this lesion. PMID:20408963

Buccoliero, Anna Maria; Castiglione, Francesca; Rossi Degl'Innocenti, Duccio; Franchi, Alessandro; Sanzo, Massimiliano; Cetica, Valentina; Giunti, Laura; Sardi, Iacopo; Mussa, Federico; Giordano, Flavio; Genitori, Lorenzo; Taddei, Gian Luigi

2011-02-01

321

Ephrin-B2 regulates endothelial cell morphology and motility independently of Eph-receptor binding.  

PubMed

The transmembrane protein ephrin-B2 regulates angiogenesis, i.e. the formation of new blood vessels through endothelial sprouting, proliferation and remodeling processes. In addition to essential roles in the embryonic vasculature, ephrin-B2 expression is upregulated in the adult at sites of neovascularization, such as tumors and wounds. Ephrins are known to bind Eph receptor family tyrosine kinases on neighboring cells and trigger bidirectional signal transduction downstream of both interacting molecules. Here we show that ephrin-B2 dynamically modulates the motility and cellular morphology of isolated endothelial cells. Even in the absence of Eph-receptor binding, ephrin-B2 stimulates repeated cycling between actomyosin-dependent cell contraction and spreading episodes, which requires the presence of the C-terminal PDZ motif. Our results show that ephrin-B2 is a potent regulator of endothelial cell behavior, and indicate that the control of cell migration and angiogenesis by ephrins might involve both receptor-dependent and receptor-independent activities. PMID:20233847

Bochenek, Magdalena L; Dickinson, Sarah; Astin, Jonathan W; Adams, Ralf H; Nobes, Catherine D

2010-04-15

322

Effect of axonal micro-tubules on the morphology of retinal nerve fibers studied by second-harmonic generation  

NASA Astrophysics Data System (ADS)

Many studies suggest that the degradation of microtubules in the retinal ganglion cells may be an early event in the progression of glaucoma. Because reflectance and birefringence of the retinal nerve fibers arise primarily from microtubules, the optical properties have been intensively studied for early detection of the disease. We previously reported a novel nonlinear optical signal from axonal microtubules for visualizing the retinal nerve fibers, namely second-harmonic generation (SHG). We demonstrate the use of axonal SHG to investigate the effect of microtubules on the morphology of the retinal nerve fiber bundles. Time-lapse SHG imaging of ex vivo rat retinal flat mounts was performed during pharmacological treatment of nocodazole, and the intensity of axonal SHG and the changes in nerve fiber bundle morphology were monitored. We found that the microtubule disruption does not lead to immediate modification in the morphology of the nerve fibers. Our results indicate that microtubular SHG may provide a useful means for sensitive detection of axonal injuries. Since the intrinsic radiation depends on the regular architecture of the cytoskeleton element as maintained by active cellular regulations, the intensity of signal reflects the health of the retinal ganglion cell axons.

Lim, Hyungsik; Danias, John

2012-11-01

323

Quantitative analysis of mitochondrial morphology and membrane potential in living cells using high-content imaging, machine learning, and morphological binning.  

PubMed

Understanding the processes of mitochondrial dynamics (fission, fusion, biogenesis, and mitophagy) has been hampered by the lack of automated, deterministic methods to measure mitochondrial morphology from microscopic images. A method to quantify mitochondrial morphology and function is presented here using a commercially available automated high-content wide-field fluorescent microscopy platform and R programming-language-based semi-automated data analysis to achieve high throughput morphological categorization (puncta, rod, network, and large & round) and quantification of mitochondrial membrane potential. In conjunction with cellular respirometry to measure mitochondrial respiratory capacity, this method detected that increasing concentrations of toxicants known to directly or indirectly affect mitochondria (t-butyl hydroperoxide [TBHP], rotenone, antimycin A, oligomycin, ouabain, and carbonyl cyanide-p-trifluoromethoxyphenylhydrazone [FCCP]), decreased mitochondrial networked areas in cultured 661w cells to 0.60-0.80 at concentrations that inhibited respiratory capacity to 0.20-0.70 (fold change compared to vehicle). Concomitantly, mitochondrial swelling was increased from 1.4- to 2.3-fold of vehicle as indicated by changes in large & round areas in response to TBHP, oligomycin, or ouabain. Finally, the automated identification of mitochondrial location enabled accurate quantification of mitochondrial membrane potential by measuring intramitochondrial tetramethylrhodamine methyl ester (TMRM) fluorescence intensity. Administration of FCCP depolarized and administration of oligomycin hyperpolarized mitochondria, as evidenced by changes in intramitochondrial TMRM fluorescence intensities to 0.33- or 5.25-fold of vehicle control values, respectively. In summary, this high-content imaging method accurately quantified mitochondrial morphology and membrane potential in hundreds of thousands of cells on a per-cell basis, with sufficient throughput for pharmacological or toxicological evaluation. PMID:25447550

Leonard, Anthony P; Cameron, Robert B; Speiser, Jaime L; Wolf, Bethany J; Peterson, Yuri K; Schnellmann, Rick G; Beeson, Craig C; Rohrer, Bärbel

2015-02-01

324

MORPHOLOGICAL TRANSFORMATION AND CHROMOSOME DAMAGE BY AMSACRINE IN C3H/10T(1/2) CLONE 8 CELLS  

EPA Science Inventory

Morphological transformation, cell survival, chromosomal aberrations and micronuclei were measured in C3H/101/2CL8 cells after 24 hour exposure to amsacrine. A weak but dose-related increase in the percentage of dishes containing transformed foci occurred. As previously reported ...

325

Morphological and morphometric study of the opossum's dorsal root ganglia neurons.  

PubMed

The ultrastructural characteristics and the morphometric evaluation of the different types of neurons present in the dorsal root ganglia (DRG) of the South American opossum (Didelphis albiventris) were studied. Four adult male animals were used and the neurons from cervical and lumbar DRG were removed and processed for histological and transmission electron microscopy observations. The morphometric data were obtained from serial sections stained by H/E and Masson's trichrome. The number of neurons in cervical and lumbar DRG was 22?300 and 31?000, respectively. About 68% of the cervical neurons and 62.5% of the lumbar neurons presented areas up to 1300?µm(2) and were considered as the small neurons of the DRG. The ultrastructural observations revealed two morphological types of neurons: clear large neurons and dark small neurons. The nuclei of both cell types are spherical and the chromatin is disperse and rarefected. The cytoplasm of the dark small neuron is more electron dense and shows a regular distribution of small mitochondria and many rough reticulum cisterns in the periphery. A small Golgi apparatus was close to the nucleus and many disperse neurofilaments occupy most parts of the cytoplasm. Smooth reticulum cisterns are rare and lipofucsin-like inclusions are present at some points. In the clear large neurons, the organelles are homogenously scattered through the cytoplasm. The neurofilaments are close packed forming bundles and small mitochondria and rough reticulum cisterns are disperse. Lipofucsin-like inclusions are more frequent in these cells. PMID:22500566

Soares, J C; Francia-Farje, L A D; Horta-Junior, J A C; Matheus, S M M

2012-01-01

326

A comparative study of the morphology of flow and spin coated P3HT:PCBM films  

NASA Astrophysics Data System (ADS)

Polymer solar cells are attractive due to the possibility of using cheaper materials and processing techniques for mass production of solar panels. Previous methods of fabricating polymer solar cells are suitable in laboratory conditions but are not scalable for industrial production. In this study, thin films of the photoactive blend of poly(3-hexylthiophene) (P3HT) and fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) were prepared by flow coating, which is suitable for industrial manufacturing of solar cells. P3HT:PCBM blends were cast from different solvents, and the morphology of flow coated and spin coated films was compared. The surface morphology and optical properties of P3HT:PCBM films were characterized with optical microscopy, AFM, and UV-vis absorption spectroscopy. The degree of P3HT order was higher in flow coated films, as compared to spin coated films. Films flow coated using chloroform solutions had a higher thermal stability and an enhanced degree of phase separation as compared to spin coated films. Flow coated films from chlorobenzene solutions had a lower thermal stability and a smaller length scale of phase separation. This study demonstrates that flow coating is a suitable alternative technique for fabricating polymer solar cells.

Chapa, Jose; Karim, Alamgir

2013-03-01

327

Three-dimensional finite element modeling of pericellular matrix and cell mechanics in the nucleus pulposus of the intervertebral disk based on in situ morphology.  

PubMed

Nucleus pulposus (NP) cells of the intervertebral disk (IVD) have unique morphological characteristics and biologic responses to mechanical stimuli that may regulate maintenance and health of the IVD. NP cells reside as single cell, paired or multiple cells in a contiguous pericellular matrix (PCM), whose structure and properties may significantly influence cell and extracellular matrix mechanics. In this study, a computational model was developed to predict the stress-strain, fluid pressure and flow fields for cells and their surrounding PCM in the NP using three-dimensional (3D) finite element models based on the in situ morphology of cell-PCM regions of the mature rat NP, measured using confocal microscopy. Three-dimensional geometries of the extracellular matrix and representative cell-matrix units were used to construct 3D finite element models of the structures as isotropic and biphasic materials. In response to compressive strain of the extracellular matrix, NP cells and PCM regions were predicted to experience volumetric strains that were 1.9-3.7 and 1.4-2.1 times greater than the extracellular matrix, respectively. Volumetric and deviatoric strain concentrations were generally found at the cell/PCM interface, while von Mises stress concentrations were associated with the PCM/extracellular matrix interface. Cell-matrix units containing greater cell numbers were associated with higher peak cell strains and lower rates of fluid pressurization upon loading. These studies provide new model predictions for micromechanics of NP cells that can contribute to an understanding of mechanotransduction in the IVD and its changes with aging and degeneration. PMID:20376522

Cao, Li; Guilak, Farshid; Setton, Lori A

2011-02-01

328

Role of RhoA activation in the growth and morphology of a murine prostate tumor cell line.  

PubMed

Prostate cancer cells derived from transgenic mice with adenocarcinoma of the prostate (TRAMP cells) were treated with the HMG-CoA reductase inhibitor, lovastatin. This caused inactivation of the small GTPase RhoA, actin stress fiber disassembly, cell rounding, growth arrest in the G1 phase of the cell cycle, cell detachment and apoptosis. Addition of geranylgeraniol (GGOL) in the presence of lovastatin, to stimulate protein geranylgeranylation, prevented lovastatin's effects. That is, RhoA was activated, actin stress fibers were assembled, the cells assumed a flat morphology and cell growth resumed. The following observations support an essential role for RhoA in TRAMP cell growth: (1) TRAMP cells expressing dominant-negative RhoA (T19N) mutant protein displayed few actin stress fibers and grew at a slower rate than controls (35 h doubling time for cells expressing RhoA (T19N) vs 20 h for untransfected cells); (2) TRAMP cells expressing constitutively active RhoA (Q63L) mutant protein displayed a contractile phenotype and grew faster than controls (13 h doubling time). Interestingly, addition of farnesol (FOL) with lovastatin, to stimulate protein farnesylation, prevented lovastatin-induced cell rounding, cell detachment and apoptosis, and stimulated cell spreading to a spindle shaped morphology. However, RhoA remained inactive and growth arrest persisted. The morphological effects of FOL addition were prevented in TRAMP cells expressing dominant-negative H-Ras (T17N) mutant protein. Thus, it appears that H-Ras is capable of inducing cell spreading, but incapable of supporting cell proliferation, in the absence of geranylgeranylated proteins like RhoA. PMID:10435593

Ghosh, P M; Ghosh-Choudhury, N; Moyer, M L; Mott, G E; Thomas, C A; Foster, B A; Greenberg, N M; Kreisberg, J I

1999-07-15

329

Morphological effects on the small-molecule-based solution-processed organic solar cells.  

PubMed

We report a proof-of-concept study on solution-processed organic solar cells (OSCs) based on [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) and structurally compact donor molecules which have dithiophene-phenazine-dithiophene (TH-P) and dithiophene-quinoxaline-dithiophene (TH-Q) configurations with decyloxy and methyl side groups, respectively. These molecules formed one-dimensional fibers through self-assembly via weak nonbonding interactions such as ?-? and van der Waals interactions even during a fast solvent removal process such as spin-casting. Photophysical and thermal properties of the new donor molecules were characterized with UV-vis absorption and fluorescence spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. The electrochemical data determined experimentally were correlated well with theoretical evaluations. The fibers from the two donor molecules showed distinct morphological differences, allowing for in-depth investigations into their influence on the OSC performance. A continuous three-dimensional network of endless one-dimensional nanofibers, with a width of 300-400 nm, were formed from TH-P regardless of the presence of PC61BM, affording spontaneous nanoscale phase separation that facilitates a large donor/acceptor interfacial area. Bulk (BHJ) and planar heterojunctions (PHJ) from TH-P/PC61BM showed a power conversion efficiency (PCE) of 0.38% and 0.30%, respectively, under optimum device conditions. Post thermal annealing led to the increased domain size and a major decrease in Jsc. Meanwhile, shorter, more rigid needles with a large thickness variation were formed from TH-Q. A continuous network of TH-Q was obtained by spin-coating only in the presence of PC61BM, and the PCE of TH-Q/PC61BM BHJ was found to be 0.36%. However, the PHJ showed poor device performance due to TH-Q's inability to form a continuous film by spin-coating. The present study suggests a basic molecular architecture to drive one-dimensional assembly and demonstrates the significance of fibrillation for small-molecule-based OSCs. PMID:25166930

Lee, Dong-Chan; Brownell, Lacie V; Yan, Liang; You, Wei

2014-09-24

330

Morphological and endocrine study of the ovarian interstitial tissue of viscacha (Lagostomus maximus maximus).  

PubMed

The morphological and endocrine aspects of the ovarian interstitial tissue of adult female viscachas were investigated to establish the probable function and the biological significance of this compartment in this rodent. Pregnant and nonpregnant adult female viscachas were used. The histological characteristics, histochemical properties, and ultrastructural features of the interstitial tissue were studied. A morphometric study was carried out to measure the relative area of lipid droplets. The progesterone and androstenedione levels in ovarian tissue as well as in serum were determined by radioimmunoassay. In this species, the histological observations showed an abundant interstitial tissue that contained a large amount of lipids. The cholesterol and its esters were present in nonpregnant females and were scarce in pregnant animals. The most ultrastructural differences were observed at mid-pregnancy. At this stage, the interstitial cells showed features that suggested higher steroidogenic activity. Furthermore, during mid-pregnancy, the relative area of lipid droplets was smaller. Both progesterone and androstenedione levels in ovarian tissue and serum were higher during pregnancy. Our results suggest that the interstitial tissue may be storage of precursor substances for the steroidogenesis via. These precursors are probably used when the endocrine requirements are high, that is, during the pregnancy. Thus, this compartment may contribute to the normal gestation of Lagostomus. However, the relation between the interstitial tissue and the pregnancy is complex, and further studies are needed to clearly establish it. PMID:17530627

Gil, Esteban; Forneris, Myriam; Domínguez, Susana; Penissi, Alicia; Fogal, Teresa; Piezzi, Ramón S; Scardapane, Luis

2007-07-01

331

Induction of maturation of human B-cell lymphomas in vitro. Morphologic changes in relation to immunoglobulin and DNA synthesis.  

PubMed Central

In vitro stimulation of cells from 8 non-Hodgkin's lymphomas comprising several histologic types with a tumor promotor (TPA) and with or without anti-immunoglobulins directed against the surface immunoglobulin of the tumor cells is reported. Morphologic transformation to immunoblastic and plasmablastic cells, but not to plasma cells, and induction of Ig and DNA synthesis were observed. A comparative analysis, including flow cytofluorometry, light microscopy combined with immunocytochemistry, and electron microscopy, suggests that the three events may not always be associated phenomena at the single-cell level even in monoclonal cell populations. Images Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 PMID:6375389

Beiske, K.; Ruud, E.; Drack, A.; Marton, P. F.; Godal, T.

1984-01-01

332

Semi-automated, Quantitative Analysis of Retinal Ganglion Cell Morphology in Mice Selectively Expressing Yellow Fluorescent Protein  

PubMed Central

The development of transgenic mouse lines that selectively label a subset of neurons provides unique opportunities to study detailed neuronal morphology and morphological changes under experimental conditions. In the present study, a mouse line in which a small number of retinal ganglion cells (RGCs) express yellow fluorescent protein (YFP) under control of the Thy-1 promoter was used (Feng et al., 2000). We characterized the number, distribution by retinal region and eccentricity of YFP-labeled RGCs using fluorescence microscopy and StereoInvestigator software (MicroBrightField, VT, USA). Then, we captured images of 4–6 YFP-expressing RGCs from each of 8 retinal regions by confocal microscopy, producing 3-dimensional and flattened data sets. A new semi-automated method to quantify the soma size, dendritic length and dendritic arbor complexity was developed using MetaMorph software (Molecular Devices, PA, USA). Our results show that YFP is expressed in 0.2% of all RGCs. Expression of YFP was not significantly different in central versus peripheral retina, but there were higher number of YFP expressing RGCs in the temporal quadrant than in the nasal. By confocal-based analysis, 58% of RGCs expressing YFP did so at a high level, with the remainder distributed in decreasing levels of brightness. Variability in detailed morphometric parameters was as great between two fellow retinas as in retinas from different mice. The analytic methods developed for this selective YFP expressing RGC model permit quantitative comparisons of parameters relevant to neuronal injury. PMID:22210127

Oglesby, Ericka; Quigley, Harry A.; Zack, Donald J.; Cone, Frances E.; Steinhart, Matthew R.; Tian, Jing; Pease, Mary E.; Kalesnykas, Giedrius

2012-01-01

333

Effects of Low PBP2b Levels on Cell Morphology and Peptidoglycan Composition in Streptococcus pneumoniae R6  

PubMed Central

Streptococcus pneumoniae produces two class B penicillin-binding proteins, PBP2x and PBP2b, both of which are essential. It is generally assumed that PBP2x is specifically involved in septum formation, while PBP2b is dedicated to peripheral cell wall synthesis. However, little experimental evidence exists to substantiate this belief. In the present study, we obtained evidence that strongly supports the view that PBP2b is essential for peripheral peptidoglycan synthesis. Depletion of PBP2b expression gave rise to long chains of cells in which individual cells were compressed in the direction of the long axis and looked lentil shaped. This morphological change is consistent with a role for pneumococcal PBP2b in the synthesis of the lateral cell wall. Depletion of PBP2x, on the other hand, resulted in lemon-shaped and some elongated cells with a thickened midcell region. Low PBP2b levels gave rise to changes in the peptidoglycan layer that made pneumococci sensitive to exogenously added LytA during logarithmic growth and refractory to chain dispersion upon addition of LytB. Interestingly, analysis of the cell wall composition of PBP2b-depleted pneumococci revealed that they had a larger proportion of branched stem peptides in their peptidoglycan than the corresponding undepleted cells. Furthermore, MurM-deficient mutants, i.e., mutants lacking the ability to synthesize branched muropeptides, were found to require much higher levels of PBP2b to sustain growth than those required by MurM-proficient strains. These findings might help to explain why increased incorporation of branched muropeptides is required for high-level beta-lactam resistance in S. pneumoniae. PMID:23873916

Berg, Kari Helene; Stamsĺs, Gro Anita; Straume, Daniel

2013-01-01

334

Comparative characterization of mouse rectum CMT93-I and -II cells by expression of claudin isoforms and tight junction morphology and function.  

PubMed

Recent studies suggest that the morphological and physiological properties of tight junctions (TJs) are determined by the combination and mixing ratios of claudin isoforms. In this study, we tried to characterize mouse cell lines by expression of claudin isoforms to use for studying epithelial TJs by overexpression or suppression of claudin(s) in the cells and found that claudin-2 was expressed in a few mouse rectum carcinoma cells, CMT93 cells. We have isolated CMT93-I and -II cells from CMT93 cells by immunohistochemical screening for the presence or absence of claudin-2 expression. Immunofluorescence and RT-PCR analyses showed that expression of claudin-4, -6, -7 and -12 was detected in both cell lines, but claudin-2 was only expressed in CMT93-II cells. There were no differences in paracellular permeability between CMT93-I and -II cells examined by 4 kDa FITC-dextran and fluorescein sodium, or in the number of TJ strands examined by freeze-fracture electron microscopy. However, the transepithelial electrical resistance (TER) of CMT93-I cells was approximately 6.5 times higher than that of CMT93-II cells, suggesting that expression of claudin-2 may be related to decreased TER. Comparative examinations of CMT93-I and -II cells provide a clue how the combination and mixing ratios of claudin isoforms regulate the paracellular permeability. PMID:18034259

Inai, Tetsuichiro; Sengoku, Akihito; Hirose, Eiji; Iida, Hiroshi; Shibata, Yosaburo

2008-02-01

335

Morphological and cultural comparison of microorganisms in surface soil and subsurface sediments at a pristine study site in Oklahoma  

Microsoft Academic Search

Surface-soil and subsurface microfloras at the site of a shallow aquifer in Oklahoma were examined and compared with respect to (1) total and viable cell numbers, (2) colony and cell types that grew on various plating media, (3) cell morphologies seen in flotation films stripped from sample particles, and (4) cellular ultrastructure. Appreciable numbers of microbial cells were present in

T. L. Bone; D. L. Balkwill

1988-01-01

336

Functions of poly-gamma-glutamic acid (?-PGA) degradation genes in ?-PGA synthesis and cell morphology maintenance.  

PubMed

Poly-?-glutamic acid (?-PGA) is an important biopolymer with greatly potential in industrial and medical applications. In the present study, we constructed a metabolically engineered glutamate-independent Bacillus amyloliquefaciens LL3 strain with considerable ?-PGA production, which was carried out by single, double, and triple markerless deletions of three degradation genes pgdS, ggt, and cwlO. The highest ?-PGA production (7.12 g/L) was obtained from the pgdS and cwlO double-deletion strain NK-pc, which was 93 % higher than that of wild-type LL3 strain (3.69 g/L). The triple-gene-deletion strain NK-pgc showed a 28 % decrease in ?-PGA production, leading to a yield of 2.69 g/L. Furthermore, the cell morphologies of the mutant strains were also characterized. The cell length of cwlO deletion strains NK-c and NK-pc was shorter than that of the wild-type strain, while the ggt deletion strains NK-g, NK-pg, NK-gc, and NK-pgc showed longer cell lengths. This is the first report concerning the markerless deletion of ?-PGA degradation genes to improve ?-PGA production in a glutamate-independent strain and the first observation that ?-glutamyltranspeptidase (encoded by ggt) could be involved in the inhibition of cell elongation. PMID:24769902

Feng, Jun; Gao, Weixia; Gu, Yanyan; Zhang, Wei; Cao, Mingfeng; Song, Cunjiang; Zhang, Peng; Sun, Min; Yang, Chao; Wang, Shufang

2014-07-01

337

Effects of simulated weightlessness on cellular morphology and biological characteristics of cell lines SGC-7901 and HFE-145.  

PubMed

We investigated the effects of simulated weightlessness on cellular morphology, proliferation, cell cycle, and apoptosis of the human gastric carcinoma cell line SGC-7901 and the human gastric normal cell line HFE-145. A rotating clinostat was used to simulate weightlessness. The Image-Pro4.5 image analysis system was used for morphometric analysis. Proliferating cell nuclear antigen expression was examined by immunohistochemical staining. Changes in the cell cycle were examined using a cytometer. Apoptosis was measured using the terminal dUTP nick-end labeling (TUNEL) method. When subjected to simulated weightlessness, the cellular morphology of SGC-7901 cells was changed at 12, 24, 48, and 72 h, cell conversion from the G1 to S phase was blocked, proliferation was inhibited at 48 and 72 h, and the apoptosis index was increased at 72 h. The same changes were observed for HFE-145 cells at 12 h when subjected to simulated weightlessness, but no significant changes were found afterward compared with controls. SGC-7901 cells change their cellular morphology and biological characteristics during clinostat-simulated weightlessness at 72 h, but HFE-145 cells only change at 12 h and adapt to simulated weightlessness after that point. PMID:25117363

Zhu, M; Jin, X W; Wu, B Y; Nie, J L; Li, Y H

2014-01-01

338

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode. Electronic supplementary information (ESI) available: Materials and equipment details, solar cell fabrication protocol, electrolyte spreading time measurement details, XPS spectra, electronic study, film adhesion test detailed analysis and field emission results. See DOI: 10.1039/c2nr32082g

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-10-01

339

The morphology of apoptosis and necrosis of fat cells after photodynamic treatment at a constant temperature in vitro  

NASA Astrophysics Data System (ADS)

Photodynamic therapy with temperature control is a new approach for treatment of obesity and cellulite. Cell death can occur under the action of various physical, chemical and biological factors. Depending on the inductor, this is apoptosis or necrosis. These two forms of cell death differ on the biochemical and morphological levels. Biochemical changes occur quickly enough and it raises difficulties of their detection. One of the morphological characteristics of apoptosis is a decrease (contraction) of cells, and necrosis - an increase in the size of the cell (swelling). This attribute simply determined visually using a digital microscope. The program was designed using LabVEIW media, which allowed us to develop the software for providing interaction with the measuring and control equipment, data collection, processing and displaying the information and results of calculations and simulations for the individual cells and ensembles of cells, and, in general, to automate process.

Yanina, Irina Yu.; Orlova, Tatyana G.; Tuchin, Valery V.; Altshuler, Gregory B.

2011-03-01

340

Polymer Solar Cells: Understanding Solvent Interactions and Morphology, and Strategies for Efficiency Improvements  

NASA Astrophysics Data System (ADS)

Organic solar cells have the potential to be unrivaled in terms of processing cost, speed, and simplicity. The simplest of such devices consists of a single bulk-heterojunction (BHJ) active layer, in which the electron donor (conjugated polymer) and electron acceptor (fullerene) are deposited from a common solvent. The performance of BHJ solar cells is strongly correlated with the nanoscale structure of the active layer. Various processing techniques have been explored to improve the nanoscale morphology of the BHJ layer, e.g. by varying the casting solvent, thermal annealing, solvent annealing, and solvent additives. An understanding of the role of residual solvent in the BHJ layer is imperative in order to develop strategies for morphology stabilization and preserve the longevity of the device. This work highlights the effect of residual solvents on acceptor, (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) diffusion and ultimately the stability of the morphology. We first show that solvent is retained within the BHJ film despite prolonged heat treatment, leading to extensive phase separation between poly(3-hexylthiophene) (P3HT) and PCBM. We then show that the addition of a small volume fraction of nitrobenzene to the casting solution inhibits the diffusion of PCBM in the film and improves the fill factor of the BHJ device without further tempering. Other commonly used additives for morphology improvement were also investigated, i.e. 1,8-diiodooctane and 1-chloronaphthalene. We show that the choice of solvent additives has direct implications on morphological evolution, i.e. P3HT:PCBM BHJ films processed with a small amount of 1,8-diiodooctane or 1-chloronaphthalene have more crystalline PCBM domains compared to crystalline P3HT domains, while the opposite is true for films cast with nitrobenzene additive and films cast purely from chlorobenzene. The BHJ film cross-links when annealed at 300°C in the presence of 1,8-diiodooctane. Cross-linking is found to occur even in pristine P3HT and PCBM films annealed under similar conditions. Our work in understanding solvent interactions greatly facilitated our venture into multi-junction solution-processed devices. In our exploration of various device architectures for optimal performance, we have also established a way to modify the surface energy of a film to render it amenable to subsequent solution-processing. The tandem architecture offers a strategy to efficiently harvest photons from the full solar spectrum by stacking multiple photoactive layers with complementary absorption spectra. We found that the current predominant choices for solution-processed electron transport layer (ETL) each have their problems when implemented into a tandem device. Hence, we are presenting the novel use of stacked perovskite, (TBA,H)Ca2Nb3O 10 (CNO), semiconductor nanosheets as an ETL and we have successfully demonstrated a completely solution-processed tandem polymer solar cell. While further optimization of the CNO-layer is still required, the robust CNO-layer can be spin-coated on top of the BHJ photoactive layer and is stable towards subsequent processing and heat-treatment. We also explored the feasibility of introducing silver nanoparticles into the device structure via a low-cost solution-processable route for the exploitation of surface plasmon resonance for near-field absorption enhancement in the photoactive layer. We find that the photo-reduction of Ag+ to Ag appears to be a promising route for in-situ deposition of Ag nanoparticles.

Chang, Lilian

341

[The morphological and karyological characteristics of MDCK and vero (B) cells cultures on plant hydrolyzate-based nutrient media].  

PubMed

MDCK and Vero (B) cell cultures were propagated during 10 passages in the experimental nutrient media containing the soybean powder hydrolyzate prepared using trypsin and bromelain enzymes and the rice powder hydrolysate prepared with trypsin and in the control DMEM and SFM4 MegaVir media. The karyological, morphological, and proliferative characteristics of continuous cultures were examined and compared. The experimental media supplied with 3% fetal bovine serum (FBS) (Gibco, U.S.A.) showed high growth-enhancing properties and failed to affect their morphology. After propagated during 10 passages in the experimental media preserved a stable karyotype. MDCK cell cultures in the nutrient media based on rice and soybean powder hydrolyzates low (2%) in FBS caused no substantial changes in the proliferation indices and morphological and karyological characteristics of cell cultures. PMID:21545033

Mikhailova, G R; Mazurkova, N A; Podchernyaeva, R Ya; Ryabchikova, E I; Troshkova, G P; Shishkina, L N

2011-01-01

342

Induction of caspase-9, biochemical assessment and morphological changes caused by apoptosis in cancer cells treated with goniothalamin extracted from Goniothalamus macrophyllus.  

PubMed

Goniothalamin, a natural compound extracted from Goniothalamus sp. belonging to the Annonacae family, possesses anticancer properties towards several tumor cell lines. This study focused on apoptosis induction by goniothalamin (GTN) in the Hela cervical cancer cell line. Cell growth inhibition was measured by MTT assay and the IC50 value of goniothalamin was 3.2 ± 0.72 ?g/ml. Morphological changes and biochemical processes associated with apoptosis were evident on phase contrast microscopy and fluorescence microscopy. DNA fragmentation, DNA damage, caspase-9 activation and a large increase in the sub-G1 and S cell cycle phases confirmed the occurrence of apoptosis in a time-dependent manner. It could be concluded that goniothalamin show a promising cytotoxicity effect against cervical cancer cells (Hela) and the cell death mode induced by goniothalamin was apoptosis. PMID:24377517

Alabsi, Aied Mohammed; Ali, Rola; Ali, Abdul Manaf; Harun, Hazlan; Al-Dubai, Sami Abdo Radman; Ganasegeran, Kurubaran; Alshagga, Mustafa Ahmed; Salem, Sameer Dirhim; Abu Kasim, Noor Hayaty Binti

2013-01-01

343

A Biochemical and Morphological Study of Rat Liver Microsomes  

Microsoft Academic Search

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

Y. Moule; C. ROUILLER; J. CHAUVEAU

1960-01-01

344

Beach morphology monitoring in the Columbia River Littoral Cell: 1997-2005  

USGS Publications Warehouse

This report describes methods used, data collected, and results of the Beach Morphology Monitoring Program in the Columbia River Littoral Cell (CRLC) from 1997 to 2005. A collaborative group primarily consisting of the US Geological Survey and the Washington State Department of Ecology performed this work. Beach Monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). Sediment size distribution data was also collected as part of this effort. The monitoring program was designed to: 1) quantify the short- to medium-term (seasonal to interannual) beach change rates and morphological variability along the CRLC and assess the processes responsible for these changes; 2) collect beach state data (i.e., grain size, beach slope, and dune/sandbar height/position) to enhance the conceptual understanding of CRLC functioning and refine predictions of future coastal change and hazards; 3) compare and contrast the scales of environmental forcing and beach morphodynamics in the CRLC to other coastlines of the world; and 4) provide beach change data in a useful format to land use managers.

Ruggiero, Peter; Eshleman, Jodi L.; Kingsley, Etienne; Thompson, David M.; Voigt, Brian; Kaminsky, George M.; Gelfenbaum, Guy

2007-01-01

345

Study on the Morphology Evolution and Purification of Electrorefined Silicon  

NASA Astrophysics Data System (ADS)

A three-layer process and apparatus have been developed for electrorefining of silicon for solar cell application. The anode is solidified from a hypereutectic solution of copper and MG silicon. At the temperature of operation (1223 K (950 °C)), elements that have an electronegativity greater than that of silicon will remain at the anode ( e.g., Cu, B, P, etc.) and then the Cu-Si phase can be used under certain conditions as a filter for purifying silicon with an electrorefining process. According to the stable liquid electrode reactive surface, high current density is possible during electrorefining and such advantages obviously improve the rate of deposition, which is a key point to reach commercial development. Deposited silicon particles are found embedded in electrolyte. Furthermore, with increasing operation time and current density, recombination of silicon particles is revealed and yields silicon balls with a diameter of 2 cm. The analysis of the anode feed and refined silicon shows a remarkable reduction of B and P concentrations, from 12.7 to 2.4 ppmw and 98.6 to 4.3 ppmw, respectively. Besides, particular mention should be made of efficient removal of impurities such as Fe, Mn, and Ti, which are present in significant quantities in the anode feed.

Lai, Yan-Qing; Jia, Ming; Tian, Zhong-Liang; Li, Jie; Yan, Jian-Feng; Yi, Ji-Guang; Wang, Zhi-Gang; Liu, Ye-Xiang

2010-04-01

346

The morphology of cells and cell organelles in the anhydrobiotic tardigrade, Macrobiotus hufelandi  

Microsoft Academic Search

Summary Anhydrobiotic and active hydrated specimens of the tardigradeMacrobiotus hufelandi were investigated by electron microscopy, and the cellular fine structure of both stages was compared. Besides conventional preparation methods, totally anhydrous techniques were used to avoid hydration artefacts in the anhydrobiotic specimens. In the latter the cytoplasm was very electron dense and masked many cell constituents, however, membraneous structures, nuclei,

B. Walz

1979-01-01

347

Segmentation of cervical cell images using mean-shift filtering and morphological operators  

NASA Astrophysics Data System (ADS)

Screening plays an important role within the fight against cervical cancer. One of the most challenging parts in order to automate the screening process is the segmentation of nuclei in the cervical cell images, as the difficulty for performing this segmentation accurately varies widely within the nuclei. We present an algorithm to perform this task. After background determination in an overview image, and interactive identification of regions of interest (ROIs) at lower magnification levels, ROIs are extracted and processed at the full magnification level of 40x. Subsequent to initial background removal, the image regions are smoothed by mean-shift and median filtering. Then, segmentations are generated by an adaptive threshold. The connected components in the resulting segmentations are filtered with morphological operators by characteristics such as shape, size and roundness. The algorithm was tested on a set of 50 images and was found to outperform other methods.

Bergmeir, C.; García Silvente, M.; Esquivias López-Cuervo, J.; Benítez, J. M.

2010-03-01

348

The active layer morphology of organic solar cells probed with grazing incidence scattering techniques.  

PubMed

Grazing incidence X-ray scattering (GIXS) provides unique insights into the morphology of active materials and thin film layers used in organic photovoltaic devices. With grazing incidence wide angle X-ray scattering (GIWAXS) the molecular arrangement of the material is probed. GIWAXS is sensitive to the crystalline parts and allows for the determination of the crystal structure and the orientation of the crystalline regions with respect to the electrodes. With grazing incidence small angle X-ray scattering (GISAXS) the nano-scale structure inside the films is probed. As GISAXS is sensitive to length scales from nanometers to several hundred nanometers, all relevant length scales of organic solar cells are detectable. After an introduction to GISAXS and GIWAXS, selected examples for application of both techniques to active layer materials are reviewed. The particular focus is on conjugated polymers, such as poly(3-hexylthiophene) (P3HT). PMID:24677365

Müller-Buschbaum, Peter

2014-12-01

349

Familial Cervical Artery Dissections Clinical, Morphologic, and Genetic Studies  

Microsoft Academic Search

Background and Purpose—Genetic risk factors are thought to play a role in the etiology of spontaneous cervical artery dissections (CAD). However, familial CAD is extremely rare. In this study we analyzed patients with familial CAD and asked the question whether familial CAD has particular features. Methods—Seven families with 15 CAD patients were recruited. All patients were carefully investigated by a

Juan Jose Martin; Ingrid Hausser; Philippe Lyrer; Otto Busse; Ralf Schwarz; Rolf Schneider; Tobias Brandt; Manja Kloss; Markus Schwaninger; Stefan Engelter; Caspar Grond-Ginsbach

2010-01-01

350

Morphological studies on natural ascites syndrome in broiler chickens  

Microsoft Academic Search

The pathology of ascites syndrome in 55 male and female broiler chickens aged 26 to 44 days was studied and compared with normal controls. At necropsy, gross changes included dark breast muscle, marked abdominal distention, presence of 40-260 ml clear yellow fluid with clots of fibrin in the abdominal cavity, hydropericardium, cardiomegaly and pericardial haemorrhages, and congestion in lungs, liver,

Azizollah Khodakaram Tafti; Mohammad Reza Karima

2000-01-01

351

The glycoprotein fibulin-3 regulates morphology and motility of olfactory ensheathing cells in vitro.  

PubMed

The primary olfactory pathway in adult mammals has retained a remarkable potential for self-repair. A specialized glial cell within the olfactory nerve, called olfactory ensheathing cell (OEC), and their associated extracellular matrix are thought to play an important role during regenerative events in this system. To gain insight into novel molecules that could mediate the OEC-supported growth of axons within the olfactory nerve, gene expression profiling experiments were conducted which revealed high expression of the glycoprotein fibulin-3 in OECs. This observation was confirmed with quantitative PCR. In vivo, the distribution of all members of the fibulin family, fibulin-3 included, was localized to the lamina propria underneath the olfactory epithelium, in close association within olfactory nerve bundles. To manipulate fibulin-3 gene expression in cultured OECs, lentiviral vector constructs were designed to either transgenically express or knock-down fibulin-3. Experimental data showed that increased levels of fibulin-3 induced profound morphological changes in cultured OECs, impeded with their migratory abilities and also suppressed OEC-mediated neurite outgrowth. Knock-down of fibulin-3 levels resulted in reduced OEC proliferation. In conclusion, the data provide novel insights into a putative role for fibulin-3 in the regulation of cell migration and neurite outgrowth within the primary olfactory pathway. PMID:18803302

Vukovic, Jana; Ruitenberg, Marc J; Roet, Kasper; Franssen, Elske; Arulpragasam, Ajanthy; Sasaki, Takako; Verhaagen, Joost; Harvey, Alan R; Busfield, Samantha J; Plant, Giles W

2009-03-01

352

Control of superlattice morphology in GaAs sub1-subxPsubx cascade cells  

NASA Technical Reports Server (NTRS)

Superlattices of GaAs(1-x)p(x) are being incorporated into cascade solar cell structures in order to reduce the dislocation density in the top cells and thus reduce recombination loss and increase output voltage. For a superlattice to effectively block the propagation of dislocations its average composition must be equal to that of the layer beneath it (from efficiency considerations for a cascade cell, the average composition should be about GaAs(.7)P(.3). When superlattices of this approximate composition were grown on GaAs by MOCVD, severe distortion of the crystal layers was observed. The essential features of this distortion are nonplanar morphology and accelerated etching in regions containing excess phosphorus and clusters of dislocations. Similar observations have been made with superlattices grown with two other MOCVD systems, indicating that the problem is of fundamental technological significance, not just an artifact of one particular growth system. The nature of the distortion effect is described, and several strategies for preventing its occurrence are presented.

Blakeslee, A. E.; Kibbler, A.

1985-01-01

353

Teneurin-3 Specifies Morphological and Functional Connectivity of Retinal Ganglion Cells in the Vertebrate Visual System  

PubMed Central

Summary A striking feature of the CNS is the precise wiring of its neuronal connections. During vertebrate visual system development, different subtypes of retinal ganglion cells (RGCs) form specific connections with their corresponding synaptic partners. However, the underlying molecular mechanisms remain to be fully elucidated. Here, we report that the cell-adhesive transmembrane protein Teneurin-3 (Tenm3) is required by zebrafish RGCs for acquisition of their correct morphological and functional connectivity in vivo. Teneurin-3 is expressed by RGCs and their presynaptic amacrine and postsynaptic tectal cell targets. Knockdown of Teneurin-3 leads to RGC dendrite stratification defects within the inner plexiform layer, as well as mistargeting of dendritic processes into outer portions of the retina. Moreover, a subset of RGC axons exhibits tectal laminar arborization errors. Finally, functional analysis of RGCs targeting the tectum reveals a selective deficit in the development of orientation selectivity after Teneurin-3 knockdown. These results suggest that Teneurin-3 plays an instructive role in the functional wiring of the vertebrate visual system. PMID:24183672

Antinucci, Paride; Nikolaou, Nikolas; Meyer, Martin P.; Hindges, Robert

2013-01-01

354

Effects of silicon nanowire morphology on optical properties and hybrid solar cell performance  

NASA Astrophysics Data System (ADS)

Silicon nanowire (SiNW) arrays are widespread applied on hybrid photovoltaic devices because SiNW arrays can substitute the pyramid texture and anti-reflection coating due to its strong light trapping. Also, SiNWs can be prepared through a cost-efficient process of metal-assisted chemical etching. However, though longer SiNW arrays have lower reflectance, the top of long SiNWs aggregate together to make junction synthesis difficult for SiNW/organic hybrid solar cell. To control and analyze the effect of SiNW array morphology on hybrid solar cells, here we change the metal deposition condition for metal-assisted chemical etching to obtain different SiNW array morphologies. The experiment was separated to two groups, by depositing metal, say, Ag, before etching (BE) or during etching (DE). For group BE, Ag was deposited on n-type Si (n-Si) wafers by thermal evaporation; then etched by H2O2 and HF. For group DE, n-Si was etched by Ag+ and HF directly. Ag was deposited on n-Si during etching process. Afterwards, residual Ag and SiO2 were removed by HNO3 and buffered HF, successively; then Ti and Ag were evaporated on the bottom of Si to be a cathode. Finally, SiNWs were stuck on the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) that was spincoated on the ITO coated glass to form SiNW/organic heterojunction. The results show that group BE has reflectance lower than that in group DE in solar spectrum. However, group BE has smaller power conversion efficiency (PCE) of 8.65% and short-circuit current density (Jsc) of 24.94 mA/cm2 than group DE of PCE of 9.47% and Jsc of 26.81 mA/cm2.

Syu, Hong-Jhang; Shiu, Shu-Chia; Hung, Yung-Jr; Lee, San-Liang; Lin, Ching-Fuh

2012-10-01

355

Neurogenic maturation of human dental pulp stem cells following neurosphere generation induces morphological and electrophysiological characteristics of functional neurons.  

PubMed

Cell-based therapies are emerging as an alternative treatment option to promote functional recovery in patients suffering from neurological disorders, which are the major cause of death and permanent disability. The present study aimed to differentiate human dental pulp stem cells (hDPSCs) toward functionally active neuronal cells in vitro. hDPSCs were subjected to a two-step protocol. First, neuronal induction was acquired through the formation of neurospheres, followed by neuronal maturation, based on cAMP and neurotrophin-3 (NT-3) signaling. At the ultrastructural level, it was shown that the intra-spheral microenvironment promoted intercellular communication. hDPSCs grew out of the neurospheres in vitro and established a neurogenic differentiated hDPSC culture (d-hDPSCs) upon cAMP and NT-3 signaling. d-hDPSCs were characterized by the increased expression of neuronal markers such as neuronal nuclei, microtubule-associated protein 2, neural cell adhesion molecule, growth-associated protein 43, synapsin I, and synaptophysin compared with nondifferentiated hDPSCs. Enzyme-linked immunosorbent assay demonstrated that the secretion of brain-derived neurotrophic factor, vascular endothelial growth factor, and nerve growth factor differed between d-hDPSCs and hDPSCs. d-hDPSCs acquired neuronal features, including multiple intercommunicating cytoplasmic extensions and increased vesicular transport, as shown by the electron microscopic observation. Patch clamp analysis demonstrated the functional activity of d-hDPSCs by the presence of tetrodotoxin- and tetraethyl ammonium-sensitive voltage-gated sodium and potassium channels, respectively. A subset of d-hDPSCs was able to fire a single action potential. The results reported in this study demonstrate that hDPSCs are capable of neuronal commitment following neurosphere formation, characterized by distinct morphological and electrophysiological properties of functional neuronal cells. PMID:25203005

Gervois, Pascal; Struys, Tom; Hilkens, Petra; Bronckaers, Annelies; Ratajczak, Jessica; Politis, Constantinus; Brône, Bert; Lambrichts, Ivo; Martens, Wendy

2015-02-01

356

Comparative Morphology, Development, and Function of Blood Cells in Nonmammalian Vertebrates  

Microsoft Academic Search

Much of our knowledge regarding vertebrate blood and blood cells is based on mammalian references. The critical study of nonmammalian vertebrate blood is relatively new, and comparatively few investigations have been published that focus on these animals' ontogeny and structure-function relationships of blood cells. Nonmammalian vertebrates comprise birds, reptiles, amphibians, and fishes, all of which have a wide range of

Juan A. Claver; Agustin I. E. Quaglia

2009-01-01

357

Yeast cell morphology and sexual reproduction – A short overview and some considerations  

Microsoft Academic Search

Over the decades, basic research in life sciences has profited greatly from the study of the small unicellular fungal species Saccharomyces cerevisiae. This yeast turned out to be key for the identification and understanding of molecular mechanisms that underlay the basic functions of all eukaryotic cells. These include, but are not limited to, the regulatory mechanisms behind cellular reproduction (cell

Michael Knop

2011-01-01

358

Morphological and oxidative alterations on Sertoli cells cytoskeleton due to retinol-induced reactive oxygen species  

Microsoft Academic Search

Retinol (vitamin A) is involved in several cellular processes, like cell division, differentiation, transformation and apoptosis. Although it has been shown that retinol is a limitant factor for all these processes, the precise mechanisms by which retinol acts are still unknown. In the present study we hypothesised that alterations in the cytoskeleton of Sertoli cells induced by retinol supplementation could

Ramatis Birnfeld de Oliveira; Fábio Klamt; Mauro A. A. Castro; Manuela Polydoro; Alfeu Zanotto Filho; Daniel Pens Gelain; Felipe Dal-Pizzol; José Cláudio Fonseca Moreira

2005-01-01

359

Vascular transfer cells in Angiosperm leaves A taxonomic and morphological survey  

Microsoft Academic Search

Summary A study of the fine structure of minor veins of mature leaves of 975 species and 242 families of Angiosperms shows that transfer cells are widespread amongst herbaceous Dicotyledons, are much rarer in woody Dicotyledons, and are virtually absent from the Monocotyledons. The evolutionary significance of the distribution of the cells amongst and within orders, families and minor groupings

J. S. Pate; B. E. S. Gunning

1969-01-01

360

Longitudinal imaging studies in schizophrenia: the relationship between brain morphology and outcome measures.  

PubMed

Imaging studies have tried to identify morphological outcome measures of schizophrenia in the last two decades. In particular, longitudinal studies have reported a correlation between larger ventricles, decreased prefrontal volumes and worse outcome. This would potentially allow to isolate subtypes of schizophrenia patients with a worse prognosis and more evident biological impairments, ultimately helping in designing specific rehabilitation interventions. PMID:21261215

Bellani, Marcella; Dusi, Nicola; Brambilla, Paolo

2010-01-01

361

[A morphological study of human hair tips by scanning electronic microscope (SEM)].  

PubMed

Morphological characteristics of human hair tip was studied by SEM. It was concluded that human hair tips could be classified into eight types. The tip formation, distribution and changes after being trimmed were explored. This study can be used in the mechanism research of human hair growth and the forensic hair examination. PMID:11938877

Ding, M

1998-01-01

362

Morphological stability of an interface between two non-Newtonian fluids moving in a Hele-Shaw cell  

NASA Astrophysics Data System (ADS)

The problem of the morphological stability of an interface in the case of the displacement of one non-Newtonian fluid by another non-Newtonian fluid in a radial Hele-Shaw cell has been considered. Both fluids have been described by the two-parameter Ostwald-de Waele power-law model. The nonzero viscosity of the displacing fluid has been taken into account. A generalized Darcy's law for the system under consideration, as well as an equation for the determination of the critical size of morphological stability with respect to harmonic perturbations (linear analysis), has been derived. Morphological phase diagrams have been constructed, and the region of the parameters in which nonequilibrium reentrant morphological transitions are possible has been revealed.

Martyushev, L. M.; Birzina, A. I.

2015-01-01

363

Predicting the morphology of sickle red blood cells using coarse-grained models of intracellular aligned hemoglobin polymers.  

PubMed

Sickle red blood cells (SS-RBCs) exhibit heterogeneous cell morphologies (sickle, holly leaf, granular, etc.) in the deoxygenated state due to the polymerization of the sickle hemoglobin. Experimental evidence points to a close relationship between SS-RBC morphology and intracellular aligned hemoglobin polymers. Here, we develop a coarse-grained (CG) stochastic model to represent the growth of the intracellular aligned hemoglobin polymer domain. The CG model is calibrated based on the mechanical properties (Young's modulus, bending rigidity) of the sickle hemoglobin fibers reported in experiments. The process of the cell membrane transition is simulated for physiologic aligned hemoglobin polymer configurations and mean corpuscular hemoglobin concentration. Typical SS-RBC morphologies observed in experiments can be obtained from the current model as a result of the intracellular aligned hemoglobin polymer development without introducing any further ad hoc assumptions. It is found that the final shape of SS-RBCs is primarily determined by the angular width of the aligned hemoglobin polymer domain, but it also depends, to a lesser degree, on the polymer growth rate and the cell membrane rigidity. Cell morphologies are quantified by structural shape factors, which agree well with experimental results from medical images. PMID:24307912

Lei, Huan; Karniadakis, George Em

2012-04-28

364

N-NITROSODIETHYLAMINE AND 4-(METHYLNITROSAMINO)-1-(3-PYRIDYL)-1-BUTANONE INDUCED MORPHOLOGICAL TRANSFORMATION OF CH3/10T1/2CL8 CELLS EXPRESSING HUMAN CYTOCHROME P450 2A6  

EPA Science Inventory

Transfection of specific genes into cells capable of expressing chemically-induced morphological cell transformation provides a valuable approach to study the mechanisms of action of carcinogens. uman cytochrome P450 isozyme, CYP2A6, has been successfully expressed from a retrovi...

365

Morphological alterations in the tympanic membrane affected by tympanosclerosis: ultrastructural study.  

PubMed

The ultrastructure of tympanoslerotic tissue, surgically excised from patients, has been studied with particular reference to the morphological changes of the connective tissue components and mineralization. Detailed analysis revealed the combination of degenerative and fibroplastic alterations, especially in the circular fibrous layer of the thickened lamina propria. In the biological material in this study the authors recognized different stages of calcium plaque development with discrete, moderate, and severe degree of mineralization. Extracellular matrix vesicles, with or without calcareous deposits, released by degenerating fibroblasts were prominent. In these biopsies no distinct morphological features of an inflammatory reaction were seen. PMID:24134073

Tukaj, Cecylia; Kuczkowski, Jerzy; Sakowicz-Burkiewicz, Monika; Gulida, Gra?yna; Tretiakow, Dymitry; Mionskowski, Tomasz; Pawe?czyk, Tadeusz

2014-04-01

366

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

PubMed

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

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

1984-01-01

367

Morphologic evidence for spatially clustered spines in apical dendrites of monkey neocortical pyramidal cells.  

PubMed

The general organization of neocortical connectivity in rhesus monkey is relatively well understood. However, mounting evidence points to an organizing principle that involves clustered synapses at the level of individual dendrites. Several synaptic plasticity studies have reported cooperative interaction between neighboring synapses on a given dendritic branch, which may potentially induce synapse clusters. Additionally, theoretical models have predicted that such cooperativity is advantageous, in that it greatly enhances a neuron's computational repertoire. However, largely because of the lack of sufficient morphologic data, the existence of clustered synapses in neurons on a global scale has never been established. The majority of excitatory synapses are found within dendritic spines. In this study, we demonstrate that spine clusters do exist on pyramidal neurons by analyzing the three-dimensional locations of ?40,000 spines on 280 apical dendritic branches in layer III of the rhesus monkey prefrontal cortex. By using clustering algorithms and Monte Carlo simulations, we quantify the probability that the observed extent of clustering does not occur randomly. This provides a measure that tests for spine clustering on a global scale, whenever high-resolution morphologic data are available. Here we demonstrate that spine clusters occur significantly more frequently than expected by pure chance and that spine clustering is concentrated in apical terminal branches. These findings indicate that spine clustering is driven by systematic biological processes. We also found that mushroom-shaped and stubby spines are predominant in clusters on dendritic segments that display prolific clustering, independently supporting a causal link between spine morphology and synaptic clustering. PMID:22315181

Yadav, Aniruddha; Gao, Yuan Z; Rodriguez, Alfredo; Dickstein, Dara L; Wearne, Susan L; Luebke, Jennifer I; Hof, Patrick R; Weaver, Christina M

2012-09-01

368

Revealing the dependence of cell spreading kinetics on its spreading morphology using microcontact printed fibronectin patterns.  

PubMed

Since the dawn of in vitro cell cultures, how cells interact and proliferate within a given external environment has always been an important issue in the study of cell biology. It is now well known that mammalian cells typically exhibit a three-phase sigmoid spreading on encountering a substrate. To further this understanding, we examined the influence of cell shape towards the second rapid expansion phase of spreading. Specifically, 3T3 fibroblasts were seeded onto silicon elastomer films made from polydimethylsiloxane (PDMS), and micro-contact printed with fibronectin stripes of various dimensions. PDMS is adopted in our study for its biocompatibility, its ease in producing very smooth surfaces, and in the fabrication of micro-contact printing stamps. The substrate patterns are compared with respect to their influence on cell spreading over time. Our studies reveal, during the early rapid expansion phase, 3T3 fibroblasts are found to spread radially following a t?ą·? law; meanwhile, they proliferated in a lengthwise fashion on the striped patterns, following a t?ą law. We account for the observed differences in kinetics through a simple geometric analysis which predicted similar trends. In particular, a t˛ law for radial spreading cells, and a tą law for lengthwise spreading cells. PMID:25551146

Huang, Cheng-Kuang; Donald, Athene

2015-01-01

369

Tailoring block copolymer morphology via control of topographical surface: A self consistent field theoretic study  

NASA Astrophysics Data System (ADS)

It is well known that chemically patterned or topologically complex substrates can direct self-assembly of adsorbed layers or thin films of block copolymers. In this study we have examined the self-assembly of a lamella-forming diblock copolymer guided by topological complexity, namely, substrates composed of trenches with different heights and widths. In general, when the substrate is neutral to both blocks of the copolymer, the perpendicular lamella morphology is obtained. However, when the substrate has a preferred affinity to one of the blocks, a host of novel morphologies including different bi-continuous network structures can be created by judiciously manipulating the trench height and width. Overall, this study clearly demonstrates the impact of this class of simulations in rational design of morphologies in thin multi-component polymeric films with application to technologies such as filtration, and high-surface area membranes.

Ye, Xianggui; Edwards, Brian J.; Khomami, Bamin

2012-02-01

370

Transgenic study of parallelism in plant morphological evolution  

PubMed Central

Developmental constraint is indicated when one finds that similar genetic mechanisms are responsible for independent origins of the same derived phenotype. We studied three independent origins of rosette flowering within the mustard family and attempted to evaluate the extent to which the same mechanisms were involved in each transition from the ancestral phenotype, inflorescence flowering. We used transformation to move a candidate gene, LFY, and its cis-regulatory sequences from rosette-flowering species into an inflorescence-flowering recipient, Arabidopsis thaliana, in place of its endogenous LFY gene. The transgenic phenotypes of experimental and control lines (containing an A. thaliana LFY transgene) and the expression driven by the cis-regulatory sequences show that changes at the LFY locus might have contributed to the evolution of rosette flowering in two of the three lineages. In the third case, changes upstream of LFY are implicated. Our data suggest that changes in a single developmental regulatory program were involved in multiple origins of the same derived trait but that the specific genetic changes were different in each case. PMID:15096600

Yoon, Ho-Sung; Baum, David A.

2004-01-01

371

Craniofacial morphologic parameters in a Persian population: an anthropometric study.  

PubMed

Limited data are available regarding the reference ranges of facial proportions of the Persian population in Iran. This study aimed to establish the reference range of craniofacial anthropometric measurements in an adult Iranian population. On 100 individuals (men = women), aged 18 to 30 years with normal faces and occlusions, 34 linear and 7 angular measurements as well as 24 indices were calculated. The difference of measurements between men and women were evaluated by paired t-test. The data were compared with the norms of North American whites using 1-sample t-test. The subjects belonged to 5 ethnic groups (57% from Fars, 14% from Kord, 11% from Azari, 10% from Gilaki-Mazani, and 2% from Lor). All head measurements were greater in men except for the head index and the head height. The subjects had leptoprosopic faces. The intercanthal width was almost one third of the biocular width and greater than the eye fissure length. Although the nose width of women was significantly smaller, both sexes had leptorrhine noses. The chin height and lower chin height were greater in men. In comparison with North American whites, considerable differences were found regarding head height and width, biocular width, nose height, face height, mouth width, and upper chin height. In conclusion, the reference range of craniofacial anthropometric measurements established for the Iranian population might be efficiently used for esthetic treatments. PMID:25203584

Amini, Fariborz; Mashayekhi, Ziba; Rahimi, Hajir; Morad, Golnaz

2014-09-01

372

Neural Crest Cell Contribution to the Developing Circulatory System Implications for Vascular Morphology?  

Microsoft Academic Search

In this study, the distribution patterns of neural crest (NC) cells (NCCs) in the developing vascular system of the chick were thoroughly studied and examined for a correlation with smooth muscle cell differentiation and vascular morphogenesis. For this purpose, we performed long-term lineage tracing using quail-chick chimera techniques and premigratory NCC infection with a replication-incompetent retrovirus containing the LacZ reporter

Maarten Bergwerff; Marlies E. Verberne; Marco C. DeRuiter; Robert E. Poelmann; Adriana C. Gittenberger-de Groot

373

Naphtho[2,1-b:3,4-b']dithiophene-based bulk heterojunction solar cells: how molecular structure influences nanoscale morphology and photovoltaic properties.  

PubMed

Organic bulk heterojunction photovoltaic devices based on a series of three naphtho[2,1-b:3,4-b']dithiophene (NDT) derivatives blended with phenyl-C71-butyric acid methyl ester were studied. These three derivatives, which have NDT units with various thiophene-chain lengths, were employed as the donor polymers. The influence of their molecular structures on the correlation between their solar-cell performances and their degree of crystallization was assessed. The grazing-incidence angle X-ray diffraction and atomic force microscopy results showed that the three derivatives exhibit three distinct nanoscale morphologies. We correlated these morphologies with the device physics by determining the J-V characteristics and the hole and electron mobilities of the devices. On the basis of our results, we propose new rules for the design of future generations of NDT-based polymers for use in bulk heterojunction solar cells. PMID:25145537

Kim, Yu Jin; Cheon, Ye Rim; Back, Jang Yeol; Kim, Yun-Hi; Chung, Dae Sung; Park, Chan Eon

2014-11-10

374

Hollow fibers - Their applications to the study of mammalian cell function  

NASA Technical Reports Server (NTRS)

The use of hollow fiber technology in cell culture and transplantation is examined. The morphologies of encapsulated pituitary cells before and after implantation into the rat are defined. Implantation experiments using hollow fibers to study mammalian cell functions are described. Consideration is given to examining somatotroph, prolactin, prostrate, fibroblast, and retinal cell functions. These experiments demonstrate that hollow fiber technology is applicable for studying mammalian cell functions.

Hymer, W. C.; Angeline, M.; Harkness, J.; Chu, M.; Grindleland, R.

1984-01-01

375

Morphological studies of laser-induced photoacoustic damage  

NASA Astrophysics Data System (ADS)

Argon-fluoride excimer laser ablation of stratum comeum causes deeper tissue damage than expected for thermal or photochemical mechanisms, suggesting thatphotoacoustic waves have arole in tissue damage. Laserirradiation (193 nm, 14 ns pulses, 1-2 Hz) attworadiantexposures, 60 and 160 mJ/cm2perpulse was usedto ablate the stratumcomeumofskin. Light and electron microscopy ofimmediate biopsies demonstrated damage to fibroblasts as deep as 88 and 220 jun, respectively, below the ablation site. Ablation throughwaterwas usedtoinertially confine the ablation zone. Partial ablationofs.c. through airproducedno damage, whereas partial ablation through water damaged skin to amean depth of 1 14.5 8.8( Full thickness ablation of s.c. through air and water produced damage zones measuring 192.2 16.2 and 293.0 71.6 rim, respectively (p <0.05). The increased depth ofdamage in the presence ofinertial confinementprovided by the layer of water strongly supports a photoacoustic mechanism ofdamage. The depths ofdamage for thelarge spot, line, and small spots were 43 1 164 urn, 269 96xni, andno damage. The spot size dependence ofthedepthofdamage is consistentwiththe geometric attenuation one would expect to be present from a pressure wave related phenomena. Sequential biopsies were taken over a 7 day period for light and transmission electron microscopy. At 24 hours, there was necrosis of the epidermis and papillary dermis subjacent to the ablation site, with neutrophils surrounding and demarcating the affected area. The necrotic zone sloughedby48 hours. Thereepithelializationwas completeby7 days. The sequenceofrepairis similartoknife wound healing which we have previously studied, and is analogous to other wound healing processes. We have used an experimental model of ArF excimer laser ablation of stratum corneum to investigate laser-induced photoacoustic damage. The evidence for the injury being due to pressure transients is indirectbutcompelling. Whether these pressuretransients are acoustic transients orshockwaves has notbeendetermined, although itis ourprejudicethatshockwaves are the predominant force under these conditions. It is important to consider the possible effects of pressure transients in evaluating laser-tissue interactions, particularly when using short pulse, high peak power lasers.

Flotte, Thomas J.; Yashima, Yutaka; Watanabe, Shinichi; McAuliffe, Daniel J., Sr.; Jacques, Steven L.

1990-06-01

376

Renal cell carcinomas with t(6;11)(p21;q12): A clinicopathologic study emphasizing unusual morphology, novel alpha-TFEB gene fusion point, immunobiomarkers, and ultrastructural features, as well as detection of the gene fusion by fluorescence in situ hybridization.  

PubMed

Renal cell carcinomas (RCCs) with t(6;11)(p21;q12) are extremely rare and characterized by specific chromosome translocation, involving the transcription factor EB (TFEB). Fewer than 30 cases have been described in the literature. We examined 7 additional cases of this rare tumor by clinicopathologic, immunohistochemical, molecular, and ultrastructural analyses. Four tumors had the typical morphologic features of TFEB RCCs, whereas 3 cases demonstrated uncommon morphologic features, mimicking epithelioid angiomyolipoma, chromophobe cell RCC, and clear cell RCC, respectively. Immunohistochemically, aside from TFEB and cathepsin K, kidney-specific cadherin was another sensitive and relatively specific marker for TFEB RCCs, supporting a distal nephron origin for these renal tumors. We also observed different ultrastructures including mitochondrion with areas of lipofuscin pigment in the smaller cells in these cases. An identical Alpha-TFEB fusion gene, 486 bp, was identified in 2 cases. In addition to the polymerase chain reaction method, we also developed a fluorescence in situ hybridization assay to serve as a cost-effective and time-efficient diagnostic tool. We detected a TFEB gene rearrangement in all 7 cases using the fluorescence in situ hybridization method. TFEB RCC seemed to be an indolent tumor. During a mean follow-up of 31 months, none of the cases developed tumor recurrence, progression, or metastasis. PMID:22895266

Rao, Qiu; Liu, Biao; Cheng, Liang; Zhu, Yun; Shi, Qun-Li; Wu, Bo; Jiang, Shao-Jun; Wang, Yan; Wang, Xuan; Yu, Bo; Zhang, Ru-Song; Ma, Heng-Hui; Lu, Zhen-Feng; Tu, Pin; Wang, Jian-Dong; Zhou, Xiao-Jun

2012-09-01

377

Effects of sustanon on the distribution of satellite cells and the morphology of skeletal muscle fibers during maturation.  

PubMed

Sustanon is one of the most commonly used anabolic androgenic drugs to increase skeletal muscle mass and strength. This drug is a blend of four esterized testosterone derivatives: Testosterone propionate, testosterone phenylpropionate, testosterone isocaproate and testosterone decanoate. Little is known about the effects of this drug on skele