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1

Studies on Morphology of Three-component Polymer Solar Cells  

NASA Astrophysics Data System (ADS)

We prepared solar cells with an active layer that contains three components, including poly(3-hexylthiophene) (P3HT), a low bandgap polymer poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']-dithiophene)-alt-4,7-(2,1,3-benzothiadiazole)] (PCPDTBT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM). P3HT and PCPDTBT have complementary light absorption spectra such that, in parallel, the two cover a very broad range of the solar spectrum. It has been demonstrated that the power conversion efficiency of the P3HT/PCPDTBT/PCBM system is enhanced over that of either P3HT/PCBM or PCPDTBT/PCBM. Understanding the morphology developed for this system, therefore, can provide valuable insight into enhancing the performance of these technologically relevant and providing a fundamental challenge in controlling the phase behavior of such mixtures that undergo ordering. Morphological studies showed that the crystallization dynamics of P3HT was influenced by the presence of PCPDTBT. There are two domains existing in the thin films, one is pure P3HT domains and another is PCBM-rich domains mixed with amorphous PCPDTBT and P3HT.

Gu, Yu; Russell, Thomas

2012-02-01

2

Morphological differences between normal and cancerous mammalian cells via multitechnique microscopic studies  

NASA Astrophysics Data System (ADS)

Despite of the recent year's important advances in breast cancer biology, there is a continuous demand for new microscopic studies able to provide complementary information on cell shape that is an essential feature of the tumour cells affecting their proliferation and spreading. Understanding the relationship between cell shape and cellular function is important for regulation of cell phenotype modification in particular during cancerogenesis. Utilizing a multitechnique approach, we have investigated the morphological differences of normal human mammalian epithelial cells (HMEC) and cancerous breast epithelial cells (MCF7) cells, both mammalian epithelial cells, but from the same cell type, allowing us to compare them. The goal of our investigation was to combine information on morphological properties of these cells provided by imaging techniques like atomic force microscopy (AFM), brightfield microscopy with in-depth images of microtubules via the multiphoton microscopy (MPM). Cells morphology studies for both cells' types were first carried out using the contact mode AFM which has gained great potential for studying biological systems. Brightfield optical imaging was operated in correlation with the AFM measurements. Topography analyses were performed for living cells as well as fixed ones for both MCF7 and HMEC 184 A1 cells. Living cancerous cells are much softer than normal ones, smaller in shape, and more difficult to manipulate. Photonic responses of fixed cells have been then evaluated by the multiphoton microscopy. Due to light's good penetration depth (IR excitation) in biological samples, MPM has already proved to be a reliable and powerful tool in medical and biological deep tissue imaging. Moreover, MPM provides useful three-dimensional information on the structural and optical properties of the specimen due to its intrinsic optical sectioning resolution. Combination of these microscopic techniques allows us to correlate external cell morphology, with in-depth images provided by the non-linear optical response of microtubules. Understanding cytoskeletal perturbations and particularly, organization of the microtubules can help us to comprehend biological processes in cancer.

Saab, Marie-Belle; Estephan, Elias; Martin, Marta; Bec, Nicole; Larroque, Christian; Cloître, Thierry; Cuisinier, Frédéric; Gergely, Csilla

2010-04-01

3

Bullous keratopathy: a study of endothelial cell morphology in patients undergoing cataract surgery.  

PubMed Central

Preoperative and postoperative endothelial cell morphology was examined in three types of patients participating in a randomised, controlled trial of cataract surgery. The first sustained modest endothelial cell loss and served as controls, the second and third sustained high cell loss, but only the latter progressed to bullous keratopathy. The technique of examining endothelial cell morphology is described and its validity assessed. Measures of cell area, number of sides, side length, and variation in cell size and cell shape were utilised. No significant differences were found between the three groups by any of the preoperative morphological measures. Furthermore, postoperative values of variation in cell shape and cell size did not differ significantly between the groups. No evidence was found in our patients to support the hypothesis that eyes at particular risk of developing bullous keratopathy may be differentiated on the basis of their preoperative or early postoperative endothelial cell morphology.

Bates, A K; Cheng, H

1988-01-01

4

In vitro effects of 2,5 hexanedione on a melanoma cell line: a morphological study.  

PubMed

The effect of 2,5 hexanedione (2,5 HD) on a cultured human melanoma cell line (JR8) was explored. The addition of the toxicant at noncytolitic concentrations (0.08-0.16%) to the monolayers for 24 and 48 h, resulted in an irreversible inhibition of cell proliferation. Cessation of melanoma cell proliferation was accompanied by wide changes in morphological features of cells still adhering to the substrate. Incubation with the toxicant seemed to induce a differentiative process characterized mainly by a significant increase in cell protrusions. Melanoma cells, losing their bipolar appearance, often increased cell size and developed long dendritic and axon-like processes sometimes ramified in distal portions. Electron microscopic observations established that a change in the polarized appearance of control cells often occurred with 2,5 HD treatment and that a regular arrangement of organelles and cytoskeletal elements was detectable within these dendritic and axon-like protrusions. Furthermore, immunocytochemical studies confirmed an involvement of microtubules and actin network within cell prolongations. After the differentiative process a necrotizing effect occurred, inducing a progressive loss of viable, dendritic cells after 4 or 5 days. Incubation with cyclic AMP was ineffective in control cells while after 2,5 HD treatment seemed to increase the survival rate of neuronal-like cells. Possible mechanisms for the growth inhibitory and differentiative effects of 2,5 HD were discussed. PMID:3029899

Malorni, W; Formisano, G; Molinari, A

1987-03-01

5

Effects of asbestiform antigorite on human alveolar epithelial A549 cells: a morphological and immunohistochemical study.  

PubMed

The purpose of the study was to investigate the biological risk of asbestiform antigorite, which is a fibrous variety of antigorite, one of the natural mineral fibres of the serpentine group to which asbestos chrysotile belongs. Asbestiform antigorite is very abundant and commonly found associated with asbestos chrysotile in serpentinites, a kind of rock outcropping present in many geographical locations worldwide. In this study we evaluated the morphological, immunohistochemical and functional effects of antigorite fibres in alveolar epithelial cancer cells (A549), a standardized human cell line currently used as a model to study cytotoxicity induced by pharmacological agents. The antigorite fibres were identified and characterized morphologically and chemically by X-ray powder diffractometry, transmission and scanning electron microscopy, both with annexed energy dispersive spectrometry. The effects of 50 microg/ml of antigorite in A549 lung cells treated at 24 and 48 h resulted in increased synthesis of VEGF, Cdc42 and beta-catenin that represent potential risks for cancer development. Phalloidin labelling showed an irregular distribution of filamentous actin resulting from antigorite contact. Our studies indicate potential cellular toxicity of antigorite in vivo, providing the opportunity to elucidate the effect of asbestos on cancer induction and possible modes of therapy. PMID:19446865

Pugnaloni, Armanda; Giantomassi, Federica; Lucarini, Guendalina; Capella, Silvana; Belmonte, Monica Mattioli; Orciani, Monia; Belluso, Elena

2010-03-01

6

Ploidy in bone marrow cells from healthy donors: a MAC (morphology antibody chromosomes) study.  

PubMed

The ploidy of human bone marrow cells belonging to the megakaryocytic, granulocytic-monocytic and erythrocytic lineages was studied by in situ hybridization using the biotin-labelled Y chromosome-specific DNA probe pY431 and the chromosome 1-specific probe pUC1.77 on cells identified morphologically and immunologically by the MAC procedure. Cells of the granulocytic-monocytic and erythrocytic lineages were seen to be 2N in ploidy, whereas the ploidy of the megakaryocytic lineage ranged from 2N to 32N, with the ploidy classes 4N and 8N being predominant. The frequency of megakaryocytes with 2N chromosomes was also high. PMID:8011532

Larramendy, M L; Nylund, S J; Wessman, M; Ruutu, T; Knuutila, S

1994-01-01

7

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

PubMed Central

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.

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

2014-01-01

8

Subcellular fractionation and morphology of calf aortic smooth muscle cells: studies on whole aorta, aortic explants, and subcultures grown under  

PubMed Central

A comparative biochemical and morphological study was made of calf aortic smooth muscle cells found in situ and grown in vitro under various conditions. Striking alterations in enzyme contents, physical properties, and morphological appearances of lysosomes, endoplasmic reticulum, plasma membranes and, to a lesser extent, mitochondria were observed upon culturing of calf aortic smooth muscle cells. These changes first appeared in cells growing out of tissue explants. They developed further upon subculturing of the cells and depended greatly on the culture conditions used. The alterations included increases in specific activities of some 5- to 25-fold of four acid hydrolases, an average ninefold increase in 5' -nucleotidase, sevenfold increase in cytochrome oxidase, and fourfold increase in neutral ?-glucosidase in subcultured smooth muscle cells compared to aortic cells in situ. Cell fractionation studies showed significant shifts in the equilibrium densities of plasma membranes, microsomes, and lysosomes, but not of mitochondria, in smooth muscle cells growing out from explants and in subcultured cells, compared to cells isolated from intact aortas. Although the cells grown in vitro exhibited typical phenotypic features of smooth muscle cells such as abundant myofilaments and surface vesicles, alterations in the morphological appearance of the endoplasmic reticulum, Golgi apparatus, and, especially, lysosomes were observed. These results demonstrate significant differences in specific cellular characteristics and functions of aortic smooth muscle cells grown in vitro compared to aortic cells in situ.

Fowler, S; Shio, H; Wolinsky, H

1977-01-01

9

Morphological studies on neuroglia  

Microsoft Academic Search

The silver-impregnation procedure of Tsujiyama is suitable for demonstration of all three classical types of neuroglial cells; in the present study it was used for electron microscopic identification of neuroglial cells in the brain of the cat. The aim of the present study was 1) to determine impregnated structural correlates of neuroglial cells at the light- and electron-microscopic levels, and

Y. Murabe; Y. Sano

1981-01-01

10

Morphological features of principal cells in the ovine epididymis: a quantitative and qualitative study.  

PubMed

Functions of the epididymis differ by region, and this may be reflected in epithelial structure. Therefore, tissues from the initial segment (IS), proximal and central caput (PCap, CCap), and proximal and central corpus (PCor, CCor) epididymidis were examined by light and transmission electron microscopy. The proportion of principal cells in the epithelium was highest (p less than 0.05) in the CCap (74%) and lowest in the CCor (68%), whereas proportions of basal cells (25%), apical cells (1.4%), and white blood cells (2%) were similar in all regions. Volume density (VD) of the nucleus was lower (p less than 0.05) in principal cells in the IS (7%) than in other regions (10%). There was no regional difference in VD of the Golgi complex (14%) or endoplasmic reticulum (19%) in principal cells. The VD of mitochondria averaged 4% in the IS through CCap, but only 2.5% in PCor or CCor (p less than 0.05). The VD of clear vesicles + multivesicular bodies (8%) and dense vesicles (6%) were higher (p less than 0.05) in the CCap than in other regions (1% each), while there were more lipid droplets (12%) in the PCor than in other regions (less than or equal to 2%). Most quantitative differences in VD of organelles within principal cells were small even though significant. However, there were profound differences in the morphological features of the Golgi complex, endoplasmic reticulum, and mitochondria among regions. PMID:2310815

Marengo, S R; Amann, R P

1990-01-01

11

Studies on Morphology and Cytochemistry in Blood Cells of Ayu Plecoglossus altivelis altivelis  

PubMed Central

ABSTRACT 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.

NAKADA, Kojin; FUJISAWA, Kuniyasu; HORIUCHI, Hiroyuki; FURUSAWA, Shuichi

2014-01-01

12

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

2014-06-01

13

Purkinje-like cells of the rat cochlear nucleus: a combined functional and morphological study.  

PubMed

Purkinje-like cells (PLCs) of the cochlear nucleus (CN) are strongly calbindin positive neurones with unknown function. In the present work functional and morphological methods have been employed to provide data about PLCs in general, and about their possible involvement in the synaptic organisation of the CN in particular. PLCs had slightly elongated soma, from which a complex dendritic arborisation extended with highly variable dimensions. On the basis of their morphology, three classes of PLCs were identified. Positively identified PLCs fired a train of action potentials on sustained depolarization. When hyperpolarizing stimuli were applied, the presence of a slowly activating, ZD7288-sensitive inward current was noted that corresponded to the h-current. PLCs received both excitatory and inhibitory synaptic inputs. Functional experiments revealed that 76% and 14% of the spontaneous inhibitory postsynaptic currents recorded from the cell bodies of the PLCs were mediated via glycinergic and GABAergic synapses, respectively. PLCs presented strong cerebellin1-like immunoreactivity, but its distribution differed from that seen in cerebellar Purkinje cells. Our results indicate that PLCs are parts of the synaptic circuitry of the CN, thus they may be actively involved in the processing and analysis of auditory information. PMID:19699723

Koszeghy, Aron; Pál, Balázs; Pap, Pál; Pocsai, Krisztina; Nagy, Zsuzsanna; Szucs, Géza; Rusznák, Zoltán

2009-11-10

14

A morphological study of the replication of Breda virus (proposed family Toroviridae) in bovine intestinal cells.  

PubMed

The morphological aspects of Breda virus serotype 2 replication in intestinal cells of gnotobiotic calves were investigated by electron microscopy. Ultrastructural findings suggest a morphogenetic pathway involving cytoplasmic vesicles, the Golgi apparatus and the cell nucleus. Virus uptake probably occurs via a receptor-mediated endocytosis-like mechanism. Endocytotic vesicles then carry virus to an as yet undetermined site of uncoating. Masses of tubules having the same diameters as Breda virion cores are found in nuclei, suggesting a role for the cell nucleus in replication of nucleocapsids. Similar tubules, as well as complete virions, were found in the Golgi region, the apparent site of virus assembly. Virus-containing Golgi vesicles then presumably move to cell surfaces where they fuse with apical and baso-lateral cell membranes to release virions in a way that permits more than one viral replicative cycle to occur without damage to host cell integrity. Virions are elongated with rounded ends and measure 42 X 100.5 nm. The morphogenesis and replication of Breda virus most closely resembles that of Berne virus of the proposed family Toroviridae. PMID:3723109

Fagerland, J A; Pohlenz, J F; Woode, G N

1986-07-01

15

Studies of mitochondrial morphology and DNA amount in the rice egg cell  

Microsoft Academic Search

In plant vegetative cells, mitochondria are usually small and grain-shaped. In contrast, unusually shaped giant mitochondria\\u000a (large cup-shaped or long stretched-rod-shaped) appear in the egg cells of geranium, maize, Ipomoea nil, and bracken. In this study, to characterize egg cell mitochondria in rice, we used nonenzymatic manual dissection to isolate\\u000a unfertilized egg cells of rice and observed the egg cell

Hideki Takanashi; Takayuki Ohnishi; Mirai Mogi; Takashi Okamoto; Shin-ichi Arimura; Nobuhiro Tsutsumi

2010-01-01

16

Morphologic spectrum of immunohistochemically characterized clear cell carcinoma of the ovary: a study of 155 cases.  

PubMed

Establishing a diagnosis of ovarian clear cell carcinoma (O-CCC) can be subject to significant interobserver variation. Accurately diagnosing this tumor is important because of its chemoresistance and reported association with Lynch syndrome. The spectrum of the morphologic features of O-CCC has not been well described in a series composed of immunohistochemically characterized cases. A total of 155 cases diagnosed as O-CCC were retrieved from the files of 3 institutions to analyze architectural and cytologic features. The immunohistochemical features of these cases have been reported earlier. A comprehensive list of features was recorded, including, but not limited to, architectural patterns, nuclear appearance, cytoplasmic characteristics, and mitotic index. Between 1 and 13 slides were available for review for each case. The cases were divided into 2 groups based on morphologic characteristics, those with features shared by the large majority (the first group, n=138) and those that showed unusual characteristics (second group, n=17). Tumors in the first group typically showed a mixture of architectural patterns, the most frequent being papillary and tubulocystic. Papillae, usually small and round and lacking hierarchical branching and tufting or stratification of more than 3 cells, were present at least focally in almost 3 of 4 cases. The cell shape was predominantly cuboidal, not columnar. Nuclear pleomorphism and prominent nucleoli were frequently present, but never diffusely. Clear cytoplasm was found in nearly every case and hobnail cells were common. Mitoses exhibited a range from 0 to 13 with an average of 3 to 4 per 10 high power fields. The second group of tumors showed numerous unusual morphologic characteristics, despite the presence of clear cytoplasm, including those typically seen in other ovarian epithelial tumors, such as serous and endometrioid carcinoma. Eighty-nine percent of tumors from the first group showed the expected "O-CCC immunophenotype" [hepatocyte nuclear factor (HNF) positive, and estrogen receptor (ER), progesterone receptor (PR), Wilms tumor 1 (WT1) and p53 negative], whereas 4% of tumors showed HNF positivity along with focal ER or PR expression. Seven percent of tumors were not immunoreactive with these markers. Twenty-nine percent of tumors in the second group showed the O-CCC immunophenotype, whereas 24% of tumors were p53 positive, 5% of tumors were WT1 positive, and the remaining cases were negative for all markers. Ninety-seven percent (112 of 117) of HNF-positive tumors in this series were classical O-CCC. Therefore, O-CCC has characteristic morphologic features and a specific, if not unique, immunophenotype in the vast majority of the cases. Clear cell-rich tumors with features that depart from the classical morphologic appearances described herein should suggest the possibility of an alternative diagnosis. PMID:21164285

DeLair, Deborah; Oliva, Esther; Köbel, Martin; Macias, Antonio; Gilks, C Blake; Soslow, Robert A

2011-01-01

17

Morphological studies on neuroglia  

Microsoft Academic Search

Immunohistochemical studies with the use of the peroxidase-antiperoxidase (PAP) method revealed that “amoeboid microglial cells”, in the brains of neonatal rats and “brain macrophages” in lesioned brains of adult rats react positively to an antiserum raised against macrophages. In brains of neonatal rats, “amoeboid microglial cells” stained by means of the PAP-method were observed in the corpus callosum, internal capsule,

Y. Murabe; Y. Sano

1983-01-01

18

Time-resolved morphological study of organic thin film solar cells based on calcium/aluminium cathode material  

NASA Astrophysics Data System (ADS)

The stability and degradation of calcium/aluminium cathode organic solar cells are investigated in situ by time-resolved energy dispersive X-ray reflectometry. They combine the good charge carrier separation and transport properties of the poly(3-hexylthiophene-2,5-diyl):C 61-butyric acid methyl ester (P3HT:PCBM) bulk heterojunction blend and the capability of the calcium/aluminium cathode to improve the fill factor and the open circuit voltage, with respect to aluminium cathodes cells. The study focuses on the crucial problem of the device structural/morphological stability in working condition. It aims to detect and control possible morphological variations at the various interfaces and to correlate these changes to the device aging.

Paci, B.; Generosi, A.; Rossi Albertini, V.; Perfetti, P.; de Bettignies, R.; Sentein, C.

2008-08-01

19

Recognition of nonkeratinizing morphology in oropharyngeal squamous cell carcinoma - a prospective cohort and interobserver variability study*  

PubMed Central

Aims Nonkeratinizing morphology in oropharyngeal squamous cell carcinoma (NKSCC) strongly correlates with human papillomavirus and p16 status, but as a unique diagnostic entity is not widely recognized by pathologists. We sought to prospectively examine the performance of a new histological typing system during 1 year of routine clinical practice (Aim 1) and also its reproducibility amongst six head and neck pathologists using a 40 case test set (Aim 2). Methods and Results The three histological types were: Type 1 (keratinizing), Type 2 (nonkeratinizing with maturation) and Type 3 (nonkeratinizing). For Aim 1, there were 85 cases. p16 immunohistochemistry was positive in five of the 18 (27.8%) cases classified as Type 1, 18 of the 19 (94.7%) as Type 2, and 47 of the 48 (97.9%) as Type 3. For Aim 2, agreement among pathologists on the test cases was best for types 1 and 3 (kappa values 0.62 and 0.56; P < 0.0001) and lowest for type 2 (kappa 0.35; P < 0.0001). All 21 cases classified as NK SCC (type 3) by any of the reviewers was p16 positive. Conclusions Pathologists can recognize NK SCC with good agreement, and when a pathologist classifies a tumour as NK SCC, this reliably predicts p16 positivity.

Lewis, James S; Khan, Raja A; Masand, Ramya P; Chernock, Rebecca D; Zhang, Qin; Al-Naief, Nasser Said; Muller, Susan; McHugh, Jonathan B; Prasad, Manju L; Brandwein-Gensler, Margaret; Perez-Ordonez, Bayardo; El-Mofty, Samir K

2013-01-01

20

An electron and fluorescence microscopic study of LLC-PK1 cells, a kidney epithelial cell line: normal morphology and cyclosporin A- and cremophor-induced alterations.  

PubMed Central

The present study demonstrates the following: (I) At high concentrations cyclosporin A is toxic to LLC-PK1 cells and at intermediate concentrations also alters intracellular morphology in this same system. Even though these cells differ morphologically from renal cortex in a number of ways, the morphological changes in this system caused by cyclosporin A resembled in certain respects its reported morphological effects in vivo. Thus, LLC-PK1 cells may provide a suitable system for investigating certain aspects of the nephrotoxicity of cyclosporin A and its underlying mechanism. (2) The cytotoxic effects of cyclosporin A on LLC-PK1 cells demonstrated a relatively distinct threshold concentration, suggesting that a threshold for in-vivo nephrotoxicity might also exist. (3) Cremophor, an oil used clinically as the vehicle for cyclosporin A, was also found to be cytotoxic towards LLC-PK1 cells at high concentrations, as well as to alter the morphology of these cells at lower concentrations. This finding supports previous suggestions that cremophor itself may have a nephrotoxic effect. (4) Finally, we have found that Nile red can be used as a fluorescent probe for the rapid and simple detection of drug-induced, lipid-rich structures in cell cultures. In addition to its use in experimental systems, Nile red might also be employed to examine biopsy material and/or to look for the occurrence of lipid-rich structures (released from disrupted cells of, e.g. the renal cortex) in urine. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7

Nassberger, L.; Bergstrand, A.; DePierre, J. W.

1991-01-01

21

Morphological studies on neuroglia  

Microsoft Academic Search

Autoradiographic studies showed that in the rat hippocampus “microglia-like reactive cells” (MRC) and astrocytes are capable of proliferation in response to kainic acid (KA)-induced lesions. A marked increase in the number of labeled MRC was observed during the first four days after the induction of the KA-lesion. A proliferative response of astrocytes occurred at two days after the KA-lesion. After

Y. Murabe; Y. Ibata; Y. Sano

1982-01-01

22

Cell morphology as an indicator of viability of cod eggs – results from an experimental study  

Microsoft Academic Search

This study evaluates the use of egg malformations, at early blastula stages, as direct indicators of egg viability in cod, Gadus morhua. Eggs with visible aberrations at early stages (4–32 cells) were incubated individually, using regular eggs as controls. Irregular eggs displayed, on an average, a lower hatching rate than the controls, 35% and 80%, respectively, but with substantial variation

Lars Vallin; Anders Nissling

1998-01-01

23

Morphologic and histochemical studies of bone cells from SL-3 rats  

NASA Technical Reports Server (NTRS)

Previous studies of rat bone following space flight indicate a significant reduction in new bone formation as a result of hypogravity. In the present study of animals from SL-3 flight, the cellular activity of the bone forming cells, the osteoblasts, was investigated. Measurements of alkaline and acid phosphatase, Golgi activity, secretory granule size, and lysosomal activity, all indicated very little difference between flight and flight-simulated controls. However, there was a tendency for osteoblasts in compact bone of flight animals to show a smaller cytoplasmic volume compared to non-flight controls. If, as in previous studies, a significant reduction in bone formation occurred, it could be due to a normal level of procollagen degradation within these smaller osteoblasts, resulting in less collagen secretion per cell.

Doty, S. B.

1985-01-01

24

Morphological and histometric study on the human Sertoli cell from birth to the onset of puberty.  

PubMed Central

In order to evaluate the changes in the number and form of the Sertoli cell from birth to the onset of puberty, a histometric and ultrastructural study was carried out in normal children. Ultrastructural findings revealed that immature Sertoli cells, present from birth to puberty, show round to elliptical nuclei, with regular outlines and small nucleoli. The cytoplasm exhibits well developed rough endoplasmic reticulum, prominent supranuclear Golgi complexes and vesicles at the luminal face; smooth endoplasmic reticulum was scarce. Histometric study revealed a progressive decrease in the Sertoli cell number per transverse tubular section as well as per unit area of testicular parenchyma, mainly from 3 years onwards. However, this decrease seemed to be the result of the progressive increase in the testicular volume as well as in the length and width of the seminiferous tubules, without change in the total Sertoli cell number per testis. This number may be considered constant, not only for adult testes but also for postnatal developing testes. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5

Nistal, M; Abaurrea, M A; Paniagua, R

1982-01-01

25

[Meibomian gland morphology study progression].  

PubMed

The meibomian gland (MG) in the eyelids, which is the largest sebaceous gland throughout the body, synthesize and secrete lipids to form the superficial tear film layer. It plays a key role in maintaining the ocular surface health. Abnormalities in meibomian gland morphology lead to meibomian gland dysfunction, which is the main cause of evaporative dry eye. Study on meibomian gland morphology will contribute significantly to the diagnosis and treatment of meibomian gland dysfunction. This review is just focusing on the current studies about techniques to visualize the morphology of the MG and changes of meibomian gland morphology related to diseases. PMID:24931156

Wang, Yuqian; Dong, Nuo; Wu, Huping

2014-04-01

26

Crystallization kinetics and morphology relations on thermally annealed bulk heterojunction solar cell blends studied by rapid heat cool calorimetry (RHC)  

NASA Astrophysics Data System (ADS)

Optimizing the post-production annealing conditions of polymer:fullerene bulk heterojunction solar cells is vitally important, not only for fine-tuning the morphology - thus increasing the efficiency - but also for retaining the desired morphology during long-term operation. However, optimal conditions for annealing temperatures and times can only be chosen, once thermal transition temperatures and annealing kinetics of the blends are well-known. For instance, for systems with glass transition temperatures (Tg) lower than the maximum device operation temperature of 80°C, the mobility needed for morphology coarsening is present, leading to efficiencies decreasing in the course of time. Using advanced fast-scanning thermal analysis techniques, the formation of nuclei and growth of crystals during heating or cooling can be reduced or avoided, and thus, the fast crystallization processes occurring during annealing of the polymer:fullerene blends can be followed. In this study, non-isothermal and isothermal crystallization kinetics of the P3HT:PCBM (poly(3-hexyl thiophene: [6,6] -phenyl C61 - butyric acid methyl ester) and P3HT:bis-PCBM blends are investigated and compared by using Rapid Heating Cooling Calorimetry (RHC).

Demir, Fatma; Van den Brande, Niko; Bertho, Sabine; Voroshazi, Eszter; Manca, Jean; Vanderzande, Dirk; Heremans, Paul; Van Mele, Bruno; Van Assche, Guy

2012-05-01

27

Morphological studies on neuroglia  

Microsoft Academic Search

Electron-microscopic survey of selectively stained microglial cells in the cerebral cortex of the rat reveals that the processes of this cell type often encircle axo-dendritic synapses. Enzyme-histochemical methods for thiamine pyrophosphatase (TPPase) or nucleoside diphosphatase (NDPase) were used for the selective marking of the microglial cells; TPPase and NDPase activities were observed in the plasma membrane of microglial cells. The

Y. Murabe; Y. Sano

1982-01-01

28

Clear cell papillary renal cell carcinoma: Incidence, morphological features, immunohistochemical profile, and biologic behavior: A single institution study.  

PubMed

This study was undertaken to determine the incidence and the clinicopathologic characteristics of those tumors that qualify as clear cell papillary renal cell carcinoma (CCPRCC) by the current definitions. From January 1, 2003 to April 30, 2013, a total of twenty-eight CCPRCC were identified (28/648, 4.3%). CCPRCC showed variable architectural patterns including cystic, papillary, tubular, and acinar. Irrespective of the architecture, the tumors were composed of cuboidal or columnar cells with clear cytoplasm, small vesicular, round or oval nuclei, and inconspicuous nucleoli. Variably thick bundles of smooth muscle actin-positive soft tissue encircled the whole tumors, forming a continuous pseudocapsule. CCPRCC strongly expressed PAX8, CA-IX, CK7, cytokeratin 34betaE12, and vimentin, and were negative for RCC, P504s/AMACR, and TFE3. On ultrastructural examination, CCPRCC showed short microvilli, cytoplasmic interdigitations, nuclear pseudoinclusions, and stromal myofibroblasts. To the best of our knowledge, this is first comprehensive ultrastructural study of CCPRCC in the literature. The major differential diagnostic considerations are clear cell renal cell carcinoma, multilocular cystic renal cell carcinoma, papillary renal cell carcinoma with clear cell changes, and Xp11.2 translocation renal cell carcinoma. CCPRCC seems to have a favorable prognosis. In the current series, none of the patients had local recurrence or metastatic disease. PMID:24485757

Alexiev, Borislav A; Drachenberg, Cinthia B

2014-04-01

29

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.

30

Physiological and morphological studies of rat pheochromocytoma cells (PC12) chemically fused and grown in culture.  

PubMed Central

Cell fusion induced by polyethylene glycol has been used to produce in culture giant multinucleate PC12 cells (up to 300 micron in diameter compared to 10-20 micron for unfused cells). Fused cells, like their unfused counterparts, were found to express various neuronal properties. They contained catecholamines. In the presence of nerve growth factor they extended long processes and expressed Na+, Ca2+, and K+ conductances generally associated with excitable cells. In the absence of nerve growth factor these cells neither grew long processes nor generated Na+-spikes. Other neuronal properties were also observed. Images

O'Lague, P H; Huttner, S L

1980-01-01

31

Morphological studies on neuroglia  

Microsoft Academic Search

The cellular response of non-neuronal elements of the pyramidal cell layer of the rat hippocampus, especially the area CA 3, was observed electron microscopically following destruction of this formation by means of intraventricular administration of kainic acid (KA).

Y. Murabe; Y. Ibata; Y. Sano

1981-01-01

32

Morphological studies on neuroglia  

Microsoft Academic Search

Light-and electron-microscopic investigations of kainic acid-induced lesions revealed a marked macrophage response and “microgliocytosis”. The hematogenous origin of reactive elements, such as brain macrophages and “microglia-like reactive cells”, was demonstrated when blood phagocytes were labeled with carbon particles or horseradish peroxidase prior to induction of the kainic acid-lesion. The induced lesion showed a proliferation of microglial cells, which led to

Y. Murabe; Y. Ibata; Y. Sano

1981-01-01

33

Recent Advances in Morphological Cell Image Analysis  

PubMed Central

This paper summarizes the recent advances in image processing methods for morphological cell analysis. The topic of morphological analysis has received much attention with the increasing demands in both bioinformatics and biomedical applications. Among many factors that affect the diagnosis of a disease, morphological cell analysis and statistics have made great contributions to results and effects for a doctor. Morphological cell analysis finds the cellar shape, cellar regularity, classification, statistics, diagnosis, and so forth. In the last 20 years, about 1000 publications have reported the use of morphological cell analysis in biomedical research. Relevant solutions encompass a rather wide application area, such as cell clumps segmentation, morphological characteristics extraction, 3D reconstruction, abnormal cells identification, and statistical analysis. These reports are summarized in this paper to enable easy referral to suitable methods for practical solutions. Representative contributions and future research trends are also addressed.

Chen, Shengyong; Zhao, Mingzhu; Wu, Guang; Yao, Chunyan; Zhang, Jianwei

2012-01-01

34

Morphological study on permeating efficiency and localization of FCLA and HpD through membrane of lung cancer cell  

NASA Astrophysics Data System (ADS)

It is reported that apoptosis of cancer cells in photodynamic therapy (PDT) is caused by 1O2 generated in photosensitization. In order to study the mechanism of this kind of 1O2-induced apoptosis, it is necessary to establish a special technique to dynamically detect intracellular production and localization of 1O2. FCLA, as a chemiluminescence probe to detect singlet oxygen (1O2) and superoxide (O2-.), has been used successfully in photodynamic and sonodynamic diagnosis in tissue level, recently. This paper reported a preliminary result of morphological study on permeating efficiency and localization of FCLA and hematoporphyrin derivative (HpD) through cellular membrane. Human lung cancer cell line (ASTC-a-1) was used in the experiment. The result of this research showed that both HpD and FCLA could permeate through cellular membrane and localize to prinuclear area, when HpD or FCLA was incubated with cells. Although the molecular weight of HpD is close to FCLA's, the permeating efficiency of HpD through membrane was different from that of FCLA. Intracellular FCLA concentration reached a peak after incubation for only 30 - 45 minutes, but amount of HpD in cells approached the equilibrium after incubation for near 22 h. In the experiment, we did not observe the evidence of FCLA or HpD penetrating into nucleolus. This study suggests that it is possibly to use a specific chemiluminescence probe to dynamcially detect the production and localization of 1O2 or 02-. in cell.

Wu, Yunxia; Xing, Da; Tang, Yonghong

2004-07-01

35

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.

2014-01-01

36

Morphodynamics and Pathology of Blood Vessels IIIComparative Morphologic Study of Contraction of Smooth Muscle Cells of Hollow Viscera and its Application to Vasoconstriction and Vasospasm  

Microsoft Academic Search

The morphologic changes in the walls of hollow viscera caused by contraction and relax ation of smooth muscle cells were studied from autopsy and surgical specimens. The specimens studied included: esophageal spasm (corkscrew and nutcracker esophagus), contraction of the lower esophageal sphincter with marked esophageal dilatation, gaseous distension of the stomach, contraction of the gastric pylorus, bladder and anal sphincter,

Ching-Shen Lin; Michael Goldfischer; Arthur Sicular; Gerald Landais; Lawrence B. Cohen

1998-01-01

37

Biomimetic modification of titanium dental implant model surfaces using the RGDSP-peptide sequence: a cell morphology study.  

PubMed

Surface topography and (bio)chemistry are key factors in determining cell response to an implant. We investigated cell adhesion and spreading patterns of epithelial cells, fibroblasts and osteoblasts on biomimetically modified, smooth and rough titanium surfaces. The RGD bioactive peptide sequence was immobilized via a non-fouling poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) molecular assembly system, which allowed exploitation of specific cell-peptide interactions even in the presence of serum. As control surfaces, bare titanium and bio-inactive surfaces (scrambled RDG and unfunctionalized PLL-g-PEG) were used. Our findings demonstrated that surface topography and chemistry directly influenced the attachment and morphology of all cell types tested. In general, an increase in cell number and more spread cells were observed on bioactive substrates (containing RGD) compared to bio-inactive surfaces. More fibroblasts were present on smooth than on rough topographies, whereas for osteoblasts the opposite tendency was observed. Epithelial cell attachment did not follow any regular pattern. Footprint areas for all cell types were significantly reduced on rough compared to smooth surfaces. Osteoblast attachment and footprint areas increased with increasing RGD-peptide surface density. However, no synergy (interaction) between RGD-peptide surface density and surface topography was observed for osteoblasts neither in terms of attachment nor footprint area. PMID:16574219

Schuler, Martin; Owen, Gethin Rh; Hamilton, Douglas W; de Wild, Michael; Textor, Marcus; Brunette, Donald M; Tosatti, Samuele G P

2006-07-01

38

Serotonin Concentration, Synthesis, Cell Origin, and Targets in the Rat Caput Epididymis During Sexual Maturation and Variations Associated With Adult Mating Status: Morphological and Biochemical Studies  

Microsoft Academic Search

The caput epididymis of some mammals contains large quantities of serotonin whose origin, targets, and physiological variations have been poorly studied. We combined morphological and biochemical techniques to begin approaching these aspects of serotonin in the rat caput epididymis. Serotonin immunostaining was detected in mast, epithelial, and neuroendocrine cells. Epithelial cells displayed immunoreactivity to 5HT1A, 5HT2A, and 5HT3 serotonin receptors.

FRANCISCO JIMENEZ-TREJO; MIGUEL TAPIA-RODRIGUEZ; DANIEL B. C. QUEIROZ; PATRICIA PADILLA; MARIA CHRISTINA W. AVELLAR; PATRICIA RIVAS MANZANO; GABRIEL MANJARREZ-GUTIERREZ; GABRIEL GUTIERREZ-OSPINA

39

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

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

1979-01-01

40

Wrinkled Membrane Morphology of Biological Cell  

NASA Astrophysics Data System (ADS)

Membranes of many biological cells possess a wrinkled surface topology that, in some instance, serves as a reservoir for providing large surface area and membrane expansion during osmotic swelling. We consider and model the development of the wrinkled morphology to result from buckling instabilities which occur during the membrane growth. In particular, we examine the wrinkled membrane morphology of white blood cell experimentally and numerically. Our results show that the deformation mismatch between the membrane and the cytoskeleton during membrane growth triggers buckling of the membrane. This behavior of the wrinkled topology enables expansion of the cell during swelling and reveals interesting details on the role of the membrane topology.

Wang, Lifeng; Castro, Carlos; Boyce, Mary

2010-03-01

41

Effects of Substrate Surface Morphology on Microcrystalline Silicon Solar Cells  

Microsoft Academic Search

The relationship between muc-Si:H solar cell performance and surface morphology of substrate is studied systematically using textured-ZnO substrate which is formed by wet etching process in order to clarify the optimum morphology of substrate for high efficiency. An average slope, \\\\tantheta, of substrate surface textures is obtained by analysis of atomic force microscopy (AFM) images, and solar cell performance is

Yoshiyuki Nasuno; Michio Kondo; Akihisa Matsuda

2001-01-01

42

Field and Modeling Studies of Nearshore Morphology.  

National Technical Information Service (NTIS)

Field and modeling studies of nearshore morphology aims to understand and predict sediment-transport mechanisms and their morphologic expression in the coastal marine environment, with particular emphasis on surf zone evolution. Principal goals are to eff...

T. G. Drake

2000-01-01

43

Rapidly recurring folliculostellate cell tumor of the adenohypophysis with the morphology of a spindle cell oncocytoma: case report with electron microscopic studies.  

PubMed

We report a rapidly recurring folliculostellate cell tumor of the adenohypophysis in a 63-year-old woman. Morphologically the tumor had the typical appearance of a spindle cell oncocytoma of the adenohypophysis. It recurred within 5 months of selective transsphenoidal resection, requiring a second transsphenoidal operation followed by radiation therapy. The spindle cell oncocytoma (SCO) of the adenohypophysis is a relatively recently described entity and a new addition to the fourth edition of the WHO Classification of Tumors of the Central Nervous System. In our case, the ultrastructural features were significantly different from those so far described in SCO, in that tumor cells formed a network of structures indistinguishable from pituitary follicles. In addition, a minority of tumor cells exhibited endocrine differentiation. PMID:19642510

Coiré, C I; Horvath, E; Smyth, H S; Kovacs, K

2009-01-01

44

Morphological studies of vertical arrays TiO2 nanotubes by electrochemical anodization technique for dye sensitized solar cell application  

NASA Astrophysics Data System (ADS)

A vertical array titanium dioxide nanotube (n-TiO2) for photovoltaic materials in dye sensitized solar cell has been synthesized by electrochemical anodization technique in NH4F aqueous solution. The morphological observation performed by SEM analysis on the scratch film showed that the distribution growths of TiO2 nanotubes on Ti subtract were uniform. The duration of growth is varied up to 12 h, with tubes length approximately 1 ?m. However, at the maximum duration, a compact TiO2 layers were formed. This phenomenon is due to the field-assisted anodic oxidation at the interfaces of Ti/TiO2 is at equal rate with the field-assisted dissolution rate of the top TiO2 nanotube's surface, resulting from the decreased quantity of F- ions to form fluoro complexes, [TiF6]2-. A slight increase in the rate of the chemical dissolution reaction produced a precipitated TiO2. Hence, [TiF6]2- complexes which are required for tubes formation are difficult to exist.

Su'ait, M. S.; Alamgir, F.; Scardi, P.; Ahmad, A.

2013-11-01

45

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

46

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.

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

2010-01-01

47

Extranodal marginal zone B-cell lymphoma of the skin: a morphologic and immunophenotypic study of 11 cases.  

PubMed

Extranodal marginal zone B-cell lymphoma (MZBL) is a recently recognized low-grade lymphoma that has been well described in other organs such as the stomach and salivary gland. It has only recently been described in skin, where it may be difficult to distinguish from reactive processes and other types of B-cell lymphoma such as follicle center lymphoma. These cases may have been classified as pseudolymphomas in the past. Extranodal MZBL was referred to as mucosa-associated lymphoid tissue (MALT) lymphoma before the Revised European-American Classification of Lymphoid Neoplasms was published in 1994. Important histologic features that aid in the diagnosis of MALT lymphoma are atypical lymphocytes (centrocyte-like and monocytoid B cells) often admixed with plasmacytoid lymphocytes, a prominent plasma cell component, lymphoepithelial lesions, intranuclear inclusions (Dutcher bodies), and reactive germinal centers that may be colonized by neoplastic cells. Immunophenotypic studies demonstrating a B-cell phenotype, light chain restriction, coexpression of CD43, and staining of atypical lymphocytes with bcl-2 support a diagnosis of MALT lymphoma. We studied 11 cases of extranodal MZBL of the skin from the Armed Forces Institute of Pathology files. There were six women and five men ranging in age from 30 to 69 years (median, 54 years). The anatomical sites included the trunk, head and neck areas, and upper extremities. There were no other sites of disease besides the skin in any of the cases. The follow-up period ranged from 5 months to 8 years (median, 24 months). Histologic results included an atypical lymphoid infiltrate with B-cell phenotype, reactive germinal centers, and a variable plasma cell component in all cases. No Dutcher bodies or lymphoepithelial lesions were noted. Extranodal MZBL of skin is a diagnostic challenge because of a heterogeneous cellular infiltrate that may be interpreted as a reactive process. The most significant neoplasm with which it is confused is follicular lymphoma. It is important to recognize the characteristic histologic and immunophenotypic features of extranodal MZBL so that the appropriate therapeutic approach may be applied. PMID:10871062

Tomaszewski, M M; Abbondanzo, S L; Lupton, G P

2000-06-01

48

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

49

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

50

A study of the Influence of mevalonic acid and its metabolites on the morphology of swiss 3T3 cells  

PubMed Central

We used two model systems to investigate the effect of compactin, a competitive inhibitor of beta-hydroxy beta-methylglutarylcoenzyme A reductase, on the shape of Swiss 3T3 cells. We maintained cells in a quiescent state in medium deficient in platelet-derived growth factor (PDGF), or we added PDGF to quiescent cells to initiate traverse through a single cell cycle. In both systems, the cells responded to compactin by acquiring a characteristic rounded shape. Cell rounding seemed to depend on an induced deficiency of mevalonic acid (MVA) since the response could be prevented or reversed by adding MVA to the culture medium. Compactin-induced rounding appeared in PDGF-stimulated cells concomitantly with a compactin-mediated inhibition of DNA synthesis, and both effects had similar sensitivities to exogenous compactin and MVA. However, cell rounding seemed to be unrelated to other, previously observed effects of MVA deficiency. Compactin did not influence the total content of cell cholesterol, and little cholesterol was formed when we added radioactive MVA to round cells to effect shape change reversal. Measurement of the dolichol-dependent glycosylation of cell protein revealed no evidence of dolichol deficiency. In addition, reversal of cell rounding by MVA was not prevented by concentrations of tunicamycin that effectively blocked the incorporation of radioactive mannose into cell protein or by concentrations of cycloheximide that blocked protein synthesis. Taken together, our results suggest a new role for MVA or its products in the maintenance of cell shape.

1982-01-01

51

Biomimetic modification of titanium dental implant model surfaces using the RGDSP-peptide sequence: A cell morphology study  

Microsoft Academic Search

Surface topography and (bio)chemistry are key factors in determining cell response to an implant. We investigated cell adhesion and spreading patterns of epithelial cells, fibroblasts and osteoblasts on biomimetically modified, smooth and rough titanium surfaces. The RGD bioactive peptide sequence was immobilized via a non-fouling poly(l-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) molecular assembly system, which allowed exploitation of specific cell–peptide interactions even in

Martin Schuler; Gethin Rh. Owen; Douglas W. Hamilton; Michael de Wild; Marcus Textor; Donald M. Brunette; Samuele G. P. Tosatti

2006-01-01

52

Rat chromosome 5 (q22-23) contains elements that control cell morphology and interactions with the extracellular matrix: a study of normal fibroblast x malignant hepatoma cell hybrids.  

PubMed

Cell interactions with the extracellular matrix are consistently modified in neoplasia. Malignant transformation has been correlated with modifications in the synthesis and distribution of matrix components and with alterations of cell adhesive properties to these components. A particular class of genes, able to suppress the transformed phenotype in normal cells, may be involved in those phenotypic changes. By studying somatic cell hybrids between mouse hepatoma (BWTG3) cells and normal rat skin fibroblasts (RSF), Islam and co-workers were able to localize a gene or a group of genes controlling anchorage dependence and cell growth in vitro. This (or these) gene(s) was (were) assigned to the q22-23 fragment of rat chromosome 5. In the present study, we compare the morphology and the interactions with the extracellular matrix proteins (laminin, fibronectin, and collagen IV) and the synthesis of these proteins by RSF X BWTG3 hybrid cells that had either retained (BS181p10) or lost (BS181a5) the q22-23 region of rat chromosome 5. Our results suggest that the rat 5q22-23 fragment controls a part of the cell differentiation program including morphology, attachment to extracellular matrix, and synthesis of some matrix proteins, particularly alpha 1 and alpha 2 chains of collagen IV. PMID:1716582

Lewalle, J M; Szpirer, C; Szpirer, J; Munaut, C; Foidart, J M

1991-10-01

53

Morphological effect of oscillating magnetic nanoparticles in killing tumor cells  

PubMed Central

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.

2014-01-01

54

Morphological effect of oscillating magnetic nanoparticles in killing tumor cells  

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

55

[Morphological and biochemical criteria for cell death].  

PubMed

The state-of-the-art of classifications of and criteria for cell death in the light of the 2009 recommendations of the Nomenclature Committee on Cell Death is presented as a lecture. Motivation is given for the necessity of using the unified criteria in the description of cell death and more than one study in its verification. The major structural and biochemical signs of four typical types of cell death--apoptosis, autophagia, keratinization, and necrosis are compared. Data are given on the major atypical forms of cell death--mitotic catastrophe, anoikis, exitotoxicity, Wallerian degeneration, paraptosis, pyroptosis, pyronecrosis, and entosis. PMID:20734836

Chernikov, V P; Belousova, T A; Kakturski?, L V

2010-01-01

56

Organochlorines and metals induce changes in the mitochondria-rich cells of fish gills: an integrative field study involving chemical, biochemical and morphological analyses.  

PubMed

Through integrating chemical, biochemical and morphological analyses, this study investigated the effects of multiple pollutants on the gill mitochondria-rich cells (MRCs) in two fish species, Astyanax fasciatus and Pimelodus maculatus, collected from five sites (FU10, FU20, FU30, FU40 and FU50) in the Furnas Hydroelectric Power Station reservoir. Water analyses revealed aluminum, iron and zinc as well as organochlorine (aldrin/dieldrin, endosulfan, heptachlor/heptachlor epoxide and metolachlor) contamination at all of the sites, with the exception of FU10. Copper, chrome, iron and zinc were detected in the gills of both species, and aldrin/dieldrin, endosulfan and heptachlor/heptachlor epoxide were detected in the gills of fish from all of the sites, with the exception of FU10. Fish collected at FU20, FU30 and FU50 exhibited numerous alterations in the surface architecture of their pavement cells and MRCs. The surface MRC density and MRC fractional area were lower in fish from FU20, FU30, FU40 and FU50 than in those from the reference site (FU10) in the winter, and some variability between the sites was observed in the summer. The organochlorine contamination at FU20 and FU50 was associated with variable changes in the MRCs and inhibition of Na(+)/K(+)-ATPase (NKA) activity, especially in P. maculatus. At FU30, the alterations in the MRCs were associated with the contaminants present, especially metals. A multivariate analysis demonstrated a positive association between the biological responses of both species and environmental contamination, indicating that under realistic conditions, a mixture of organochlorines and metals affected the MRCs by inhibiting NKA activity and inducing morphological changes, which may cause an ionic imbalance. PMID:23220410

Fernandes, M N; Paulino, M G; Sakuragui, M M; Ramos, C A; Pereira, C D S; Sadauskas-Henrique, H

2013-01-15

57

Morphological Study of Lumbricals - A Cadaveric Study  

PubMed Central

The apparently simple human function of closing the hand to grasp an object or opening the palm to release it are in reality tasks of considerable mechanical complexity requiring the contraction of many individual muscles Lumbricals are important part of intrinsic musculature of hand. Though several deviations from normal have been described in standard textbooks of anatomy, a review of basic anatomy of lumbricals will be helpful. Aim: Proper knowledge about anatomy and variaitions prevalent in intrinsic musculature of hand is mandatory for various surgical procedure like cleft hand surgery, pollicization & other digital transposition procedures Present study was conducted to study morphology & variations prevalent in this region. The results were compiled and tried to find out commonest variations Phylogenetical & ontogenetical basis and clinical applications related to variations encountered were tried to know by correlating it with available literature. Material & Methods: For this study 50 hands of formalin embalmed cadavers were dissected The limbs were labelled R OR L for right or left, M or F for male or female. Cunnigham’s manual for dissection was followed for dissection. Results: Origin and nerve supply of lumbricals was normal in all hands. The variations were encountered in insertion of the 3rd lumbrical (32%) and 4th lumbrical (24%) were more confined to the right hand. Variations encountered commonly were split and misplaced insertion of third & fourth lumbricals. These variations are critically analyzed in the light of accessible literature. Conclusion: Lumbricals are more variable in the insertion rather than the origin & nerve supply. The variation commonly seen were split & misplaced insertion Split insertion was common in the third lumbrical whereas misplaced insertion is more common in the fourth lumbrical Variations are more common on right hands.

Parminder, Kaur

2013-01-01

58

Time-resolved morphological study of organic thin film solar cells based on calcium\\/aluminium cathode material  

Microsoft Academic Search

The stability and degradation of calcium\\/aluminium cathode organic solar cells are investigated in situ by time-resolved energy dispersive X-ray reflectometry. They combine the good charge carrier separation and transport properties of the poly(3-hexylthiophene-2,5-diyl):C61-butyric acid methyl ester (P3HT:PCBM) bulk heterojunction blend and the capability of the calcium\\/aluminium cathode to improve the fill factor and the open circuit voltage, with respect to

B. Paci; A. Generosi; V. Rossi Albertini; P. Perfetti; R. de Bettignies; C. Sentein

2008-01-01

59

Nanoscale Morphology of High-Performance Polymer Solar Cells  

Microsoft Academic Search

Transmission electron microscopy and electron diffraction are used to study the changes in morphology of composite films of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM) in bulk heterojunction solar cells. Thermal annealing produces and stabilizes a nanoscale interpenetrating network with crystalline order for both components. P3HT forms long, thin conducting nanowires in a rather homogeneous, nanocrystalline PCBM film. Both the

Xiaoniu Yang; Joachim Loos; Sjoerd C. Veenstra; Wiljan J. H. Verhees; Martijn M. Wienk; Jan M. Kroon; Matthias A. J. Michels; René A. J. Janssen

2005-01-01

60

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

Microsoft Academic Search

The cytological changes induced in rat liver cells by the aminoazo dye 2-Me-DAB have been examined by light and electron microscopy. It is observed that this non-carcinogenic com- pound duplicates most of the morphological alterations produced by other hepatotoxins, some of which, such as the closely related aminoazo dye 3~-Me-DAB, are potent carcinogens. These non-specific effects involve both the granular

J. G. Lafontaine; C. ALLARD

1964-01-01

61

Developmental mechanisms that regulate retinal ganglion cell dendritic morphology  

PubMed Central

One of the fundamental features of retinal ganglion cells (RGCs) is that dendrites of individual RGCs are confined to one or a few narrow strata within the inner plexiform layer (IPL), and each RGC synapses only with a small group of presynaptic bipolar and amacrine cells with axons/dendrites ramified in the same strata to process distinct visual features. The underlying mechanisms which control the development of this laminar-restricted distribution pattern of RGC dendrites have been extensively studied, and it is still an open question whether the dendritic pattern of RGCs is determined by molecular cues or by activity-dependent refinement. Accumulating evidence suggests that both molecular cues and activity-dependent refinement might regulate RGC dendrites in a cell subtype-specific manner. However, identification of morphological subtypes of RGCs before they have achieved their mature dendritic pattern is a major challenge in the study of RGC dendritic development. This problem is now being circumvented through the use of molecular markers in genetically engineered mouse lines to identify RGC subsets early during development. Another unanswered fundamental question in the study of activity-dependent refinement of RGC dendrites is how changes in synaptic activity lead to the changes in dendritic morphology. Recent studies have started to shed light on the molecular basis of activity-dependent dendritic refinement of RGCs by showing that some molecular cascades control the cytoskeleton reorganization of RGCs.

Tian, Ning

2011-01-01

62

Squamous cell carcinoma: morphological & topographical spectrum: a two year analysis.  

PubMed

Squamous cell carcinoma, which is a malignant tumor of the squamous epithelium, has been a major cause of morbidity and mortality worldwide. It is a major health problem across the world and among the most common cancers seen in both Indian men and women as can be gauged from the records of the National Cancer Registry Programme. This study was undertaken to analyze the spectrum of squamous cell carcinoma cases presenting at M.Y. Hospital, Indore, during 2 years between 2007 and 2008, to understand the morphological patterns of squamous cell carcinoma lesions and classify them into morphological categories given by International Classification of Diseases for Oncology (ICD-O, third edition), to analyze the anatomical site distribution pattern of squamous cell carcinoma lesions and categorize them in topographical classes given by ICD-O. Over a 2-year period, 959 cases were retrieved from the files of histopathology laboratory, department of pathology, M.G.M. Medical College, Indore. Out of total 959 cases, the maximum cases-290 (30.24 %)-of squamous cell carcinoma were found between the fourth and fifth decades of life. The frequency of squamous cell carcinoma in patients older than 30 years was 96.35 %, while in cases of less than 30 years, it was 03.65 %. Most of the reported cases of squamous cell carcinoma included invasive types (i.e., 94.3 %). Cases with distant metastasis constituted 4.7 %, while only 1 % were noninvasive or in situ. The frequency of squamous cell carcinoma presenting at our institution was highest among those involving the lip, oral cavity, and pharynx (56.50 %), followed by those involving female genital organs (30.24 %). The respective involvement of skin, digestive organs, and respiratory systems was 4.70, 3.86, and 2.40 % in decreasing order of frequency. Frequency was least (1.05 %) among the cases reported to show metastatic deposits of squamous cell carcinoma in lymph nodes. Regarding the topographical spectrum, the maximum number of cases (26.07 %) of squamous cell carcinoma encountered belonged to ICD-O category C-53 (i.e., cervix). Among the morphological categories, the most frequently encountered was that of squamous cell carcinoma, keratinizing (35.2 %). PMID:24891773

Narang, Sanjeev; Kanungo, Namrata; Jain, Ravi

2014-04-01

63

Corneal endothelial cell density and morphology in healthy Turkish eyes.  

PubMed

Purpose. To describe the normative values of corneal endothelial cell density, morphology, and central corneal thickness in healthy Turkish eyes. Methods. Specular microscopy was performed in 252 eyes of 126 healthy volunteers (M?:?F, 42?:?84). Parameters studied included mean endothelial cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and central corneal thickness (CCT). Results. The mean age of volunteers was 44.3 ± 13.5 (range, 20 to 70) years. There was a statistically significant decrease in MCD (P < 0.001; correlation, -0.388) and percentage of hexagonal cells, (P < 0.001; correlation, -0.199) with age. There was also a statistically significant increase in MCA (P < 0.001; correlation, 0.363) with increasing age. There was no statistically significant difference in MCD, MCA, CV in cell size, percentage of hexagonal cells, and CCT between genders and there was also no significant difference in these parameters between fellow eyes of subjects. Conclusions. Normotive data for the endothelium in the Turkish population are reported. Endothelial cell density in the Turkish eyes is less than that described in the Japanese, American, Chinese, and Filipino eyes and higher than that described in Indian, Thai, and Iranian eyes. PMID:24683494

Ar?c?, Ceyhun; Arslan, Osman Sevki; Dikkaya, Funda

2014-01-01

64

Corneal Endothelial Cell Density and Morphology in Healthy Turkish Eyes  

PubMed Central

Purpose. To describe the normative values of corneal endothelial cell density, morphology, and central corneal thickness in healthy Turkish eyes. Methods. Specular microscopy was performed in 252 eyes of 126 healthy volunteers (M?:?F, 42?:?84). Parameters studied included mean endothelial cell density (MCD), mean cell area (MCA), coefficient of variation (CV) in cell size, percentage of hexagonal cells, and central corneal thickness (CCT). Results. The mean age of volunteers was 44.3 ± 13.5 (range, 20 to 70) years. There was a statistically significant decrease in MCD (P < 0.001; correlation, ?0.388) and percentage of hexagonal cells, (P < 0.001; correlation, ?0.199) with age. There was also a statistically significant increase in MCA (P < 0.001; correlation, 0.363) with increasing age. There was no statistically significant difference in MCD, MCA, CV in cell size, percentage of hexagonal cells, and CCT between genders and there was also no significant difference in these parameters between fellow eyes of subjects. Conclusions. Normotive data for the endothelium in the Turkish population are reported. Endothelial cell density in the Turkish eyes is less than that described in the Japanese, American, Chinese, and Filipino eyes and higher than that described in Indian, Thai, and Iranian eyes.

Ar?c?, Ceyhun; Arslan, Osman Sevki; Dikkaya, Funda

2014-01-01

65

The morphology of myeloma cells changes with progression of the disease  

PubMed Central

Aim of the study Multiple myeloma is a heterogeneous entity with variable course. Plasma cells found in bone marrow smears are characterised by extremely high diversity of morphology. We have attempted to determine whether the morphological characteristics of myeloma cells vary with the natural course of the disease. We investigated the incidence of selected morphological features and planimetric parameters of myeloma cells present in bone marrow smears. Material and methods Material collected from 103 patients was evaluated at diagnosis and then during relapse. It was found that in the same patients, plasma cell morphology changes in the course of the disease: cell surface, nucleus surface, tumour cell anisocytosis and nuclear-cytoplasmic ratio increase significantly. Results The results suggest that some morphological features are more common in clinically advanced disease. These include the number of nucleoli, the number of myeloma cells with irregular nuclei, and larger nuclei. Using the classification systems according to Greipp and Goasguen, we have noted changes in morphological pattern of myeloma cells in some patients with progressive multiple myeloma. This was associated with the appearance of a cell clone characterised by a set of traits indicating a low degree of maturity. Conclusions We did not find that the type and intensity of cytostatic therapy significantly affect the morphology of plasma cells. Therefore, we suggest that some changes are due to natural, expansive course of the disease.

Sawicki, Waldemar

2013-01-01

66

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.

Ovadia, Jeremy; Nie, Qing

2013-01-01

67

Stem cell niche structure as an inherent cause of undulating epithelial morphologies.  

PubMed

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

68

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

69

The effect of morphology upon electrophysiological responses of retinal ganglion cells: simulation results.  

PubMed

Retinal ganglion cells (RGCs) display differences in their morphology and intrinsic electrophysiology. The goal of this study is to characterize the ionic currents that explain the behavior of ON and OFF RGCs and to explore if all morphological types of RGCs exhibit the phenomena described in electrophysiological data. We extend our previous single compartment cell models of ON and OFF RGCs to more biophysically realistic multicompartment cell models and investigate the effect of cell morphology on intrinsic electrophysiological properties. The membrane dynamics are described using the Hodgkin - Huxley type formalism. A subset of published patch-clamp data from isolated intact mouse retina is used to constrain the model and another subset is used to validate the model. Two hundred morphologically distinct ON and OFF RGCs are simulated with various densities of ionic currents in different morphological neuron compartments. Our model predicts that the differences between ON and OFF cells are explained by the presence of the low voltage activated calcium current in OFF cells and absence of such in ON cells. Our study shows through simulation that particular morphological types of RGCs are capable of exhibiting the full range of phenomena described in recent experiments. Comparisons of outputs from different cells indicate that the RGC morphologies that best describe recent experimental results are ones that have a larger ratio of soma to total surface area. PMID:23835760

Maturana, Matias I; Kameneva, Tatiana; Burkitt, Anthony N; Meffin, Hamish; Grayden, David B

2014-04-01

70

Cell behavior on microparticles with different surface morphology  

Microsoft Academic Search

Microparticles can serve as substrates for cell amplification and deliver the cell aggregation to the site of the defect for tissue regeneration. To develop favorable microparticles for cell delivery application, we fabricated and evaluated three types of microparticles that differ in surface properties. The microparticles with varied surface morphology (smooth, pitted and multicavity) were created from chemically crosslinked gelatin particles

Sha Huang; Xiaobing Fu

2010-01-01

71

Mucinous tubular and spindle cell carcinoma of the kidney with prominent papillary component, a non-classic morphologic variant. A histologic, immunohistochemical, electron microscopic and fluorescence in situ hybridization study.  

PubMed

Mucinous tubular and spindle cell carcinoma (MTSCC) is a rare type of kidney tumor with relatively indolent behavior. Non-classic morphological variants have not been well studied and rarely been reported. We report a challenging case MTSCC with a peculiar morphology in a 42-year-old man, arising in a background of end-stage renal disease (ESRD). Predominant areas with extensive papillary architecture, psammoma bodies and stromal macrophageal aggregates, reminiscent of a papillary renal cell carcinoma (papillary RCC), were intermixed with foci that transitioned into a MTSCC-like morphology exhibiting elongated tubules and a low grade spindle cell component in a background of mucinous stroma. Immunohistochemistry demonstrated diffuse positivity for P504s/AMACR and vimentin in tumor cells. Focal positivity for RCC, CD10 and CK7 was also noted. Kidney-specific cadherin, cytokeratin 34betaE12 and TFE3 stains were negative in the tumor. The major differential diagnostic considerations were papillary RCC, clear cell papillary RCC, and Xp11.2 translocation carcinoma. Negative FISH studies for trisomy 7 and 17 in both papillary and spindled components supported the diagnosis of MTSCC. The ultrastructural profile was not entirely indicative of the cellular origin of the tumor. Cytogenetic analysis should be performed in atypical cases of MTSCC for precise diagnosis. PMID:24702883

Alexiev, Borislav A; Burke, Allen P; Drachenberg, Cinthia B; Richards, Stephanie M; Zou, Ying S

2014-07-01

72

Influence of manganese on morphology and cell wall composition of Aspergillus niger during citric acid fermentation  

Microsoft Academic Search

Morphology and cell wall composition of Aspergillus niger were studied under conditions of manganese sufficient or deficient cultivation in an otherwise citric acid producing medium. Omission of Mn2+ (less than 10-7 M) from the nutrient medium of Aspergillus niger results in abnormal morphological development which is characterized by increased spore swelling, and squat, bulbeous hyphae. Fractionation and analysis of manganese

Monika Kisser; C. P. Kubicek; M. Röhr

1980-01-01

73

Development of Morphological Instability and Cells During Rapid Solidification of Laser Annealed Silicon Alloys.  

National Technical Information Service (NTIS)

The details of morphological instability occurring during rapid solidification have been studied in In exp + , Ga exp + , Sb exp + , Bi exp + , Ge exp + , Fe exp + and Cr exp + implanted silicon specimens after pulsed laser annealing. The average cell siz...

J. Narayan C. W. White

1981-01-01

74

The morphologic and immunohistochemical spectrum of papillary renal cell carcinoma: study including 132 cases with pure type 1 and type 2 morphology as well as tumors with overlapping features.  

PubMed

Papillary renal cell carcinomas (pRCC) are classically divided into type 1 and 2 tumors. However, many cases do not fulfill all the criteria for either type. We describe the clinical, morphologic, and immunohistochemical (IHC) features of 132 pRCCs to better characterize the frequency and nature of tumors with overlapping features. Cases were reviewed and classified; IHC evaluation of CK7, EMA, TopoII?, napsin A, and AMACR was performed on 95 cases. The frequencies of type 1, type 2, and "overlapping" pRCC were 25%, 28%, and 47%, respectively. The 2 categories of "overlapping" tumors were: (1) cases with bland cuboidal cells but no basophilic cytoplasm (type A); and (2) cases with predominantly type 1 histology admixed with areas showing prominent nucleoli (type B). The pathologic stage of "overlapping" cases showed concordance with type 1 tumors. Using the 2 discriminatory markers (CK7, EMA), "type A" cases were similar to type 1. Although the high-nuclear grade areas of "type B" tumors showed some staining differences from their low-nuclear grade counterpart, their IHC profile was closer to type 1. Single nucleotide polymorphism array results, although preliminary and restricted to only 9 cases (3 with overlapping features), also seemed to confirm those findings. In conclusion, we demonstrate that variations in cytoplasmic quality and/or presence of high-grade nuclei in tumors otherwise displaying features of type 1 pRCCs are similar in stage and IHC profile those with classic type 1 histology, suggesting that their spectrum might be wider than originally described. PMID:24919183

Chevarie-Davis, Myriam; Riazalhosseini, Yasser; Arseneault, Madeleine; Aprikian, Armen; Kassouf, Wassim; Tanguay, Simon; Latour, Mathieu; Brimo, Fadi

2014-07-01

75

The biogenesis protein PEX14 is an optimal marker for the identification and localization of peroxisomes in different cell types, tissues, and species in morphological studies.  

PubMed

Catalase and ABCD3 are frequently used as markers for the localization of peroxisomes in morphological experiments. Their abundance, however, is highly dependent on metabolic demands, reducing the validity of analyses of peroxisomal abundance and distribution based solely on these proteins. We therefore attempted to find a protein which can be used as an optimal marker for peroxisomes in a variety of species, tissues, cell types and also experimental designs, independently of peroxisomal metabolism. We found that the biogenesis protein peroxin 14 (PEX14) is present in comparable amounts in the membranes of every peroxisome and is optimally suited for immunoblotting, immunohistochemistry, immunofluorescence, and immunoelectron microscopy. Using antibodies against PEX14, we could visualize peroxisomes with almost undetectable catalase content in various mammalian tissue sections (submandibular and adrenal gland, kidney, testis, ovary, brain, and pancreas from mouse, cat, baboon, and human) and cell cultures (primary cells and cell lines). Peroxisome labeling with catalase often showed a similar tissue distribution to the mitochondrial enzyme mitochondrial superoxide dismutase (both responsible for the degradation of reactive oxygen species), whereas ABCD3 exhibited a distinct labeling only in cells involved in lipid metabolism. We increased the sensitivity of our methods by using QuantumDots™, which have higher emission yields compared to classic fluorochromes and are unsusceptible to photobleaching, thereby allowing more exact quantification without artificial mistakes due to heterogeneity of individual peroxisomes. We conclude that PEX14 is indeed the best marker for labeling of peroxisomes in a variety of tissues and cell types in a consistent fashion for comparative morphometry. PMID:23959168

Grant, Phillip; Ahlemeyer, Barbara; Karnati, Srikanth; Berg, Timm; Stelzig, Ingra; Nenicu, Anca; Kuchelmeister, Klaus; Crane, Denis I; Baumgart-Vogt, Eveline

2013-10-01

76

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.

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

2012-01-01

77

Counting white blood cells using morphological granulometries  

Microsoft Academic Search

We describe a modification of the mixture proportion estimation algorithm based on the granulometric mixing theorem. The modified algorithm is applied to the problem of counting different types of white blood cells in bone marrow images. In principle, the algorithm can be used to count the proportion of cells in each class without explicitly segmenting and classifying them. The direct

Nipon Theera-Umpon; Paul D. Gader

2000-01-01

78

Neuronize: a tool for building realistic neuronal cell morphologies  

PubMed Central

This study presents a tool, Neuronize, for building realistic three-dimensional models of neuronal cells from the morphological information extracted through computer-aided tracing applications. Neuronize consists of a set of methods designed to build 3D neural meshes that approximate the cell membrane at different resolution levels, allowing a balance to be reached between the complexity and the quality of the final model. The main contribution of the present study is the proposal of a novel approach to build a realistic and accurate 3D shape of the soma from the incomplete information stored in the digitally traced neuron, which usually consists of a 2D cell body contour. This technique is based on the deformation of an initial shape driven by the position and thickness of the first order dendrites. The addition of a set of spines along the dendrites completes the model, building a final 3D neuronal cell suitable for its visualization in a wide range of 3D environments.

Brito, Juan P.; Mata, Susana; Bayona, Sofia; Pastor, Luis; DeFelipe, Javier; Benavides-Piccione, Ruth

2013-01-01

79

Nanoparticle Induced Cell Magneto-Rotation: Monitoring Morphology, Stress and Drug Sensitivity of a Suspended Single Cancer Cell  

PubMed Central

Single cell analysis has allowed critical discoveries in drug testing, immunobiology and stem cell research. In addition, a change from two to three dimensional growth conditions radically affects cell behavior. This already resulted in new observations on gene expression and communication networks and in better predictions of cell responses to their environment. However, it is still difficult to study the size and shape of single cells that are freely suspended, where morphological changes are highly significant. Described here is a new method for quantitative real time monitoring of cell size and morphology, on single live suspended cancer cells, unconfined in three dimensions. The precision is comparable to that of the best optical microscopes, but, in contrast, there is no need for confining the cell to the imaging plane. The here first introduced cell magnetorotation (CM) method is made possible by nanoparticle induced cell magnetization. By using a rotating magnetic field, the magnetically labeled cell is actively rotated, and the rotational period is measured in real-time. A change in morphology induces a change in the rotational period of the suspended cell (e.g. when the cell gets bigger it rotates slower). The ability to monitor, in real time, cell swelling or death, at the single cell level, is demonstrated. This method could thus be used for multiplexed real time single cell morphology analysis, with implications for drug testing, drug discovery, genomics and three-dimensional culturing.

Elbez, Remy; McNaughton, Brandon H.; Patel, Lalit; Pienta, Kenneth J.; Kopelman, Raoul

2011-01-01

80

Effects of chard ( Beta vulgaris L. var. cicla) extract on pancreatic B cells in streptozotocin-diabetic rats: a morphological and biochemical study  

Microsoft Academic Search

Chard (Beta vulgaris L. var. cicla) is used as a hypoglycemic agent by diabetic patients in Turkey. The present study was carried out in order to detect whether this plant, used in folk remedies for decreasing blood glucose levels, affects pancreatic B cells and blood glucose. In the diabetic group, a decrease in the number of B cells of Langerhans

? Bolkent; R Yanarda?; A Tabako?lu-O?uz; Ö Özsoy-Saçan

2000-01-01

81

Clinicopathologic study of 62 acinar cell carcinomas of the pancreas: insights into the morphology and immunophenotype and search for prognostic markers.  

PubMed

Acinar cell carcinoma (ACC) of the pancreas is a very rare tumor that has various morphologic features, which may give rise to diagnostic difficulties. Because of its rarity, many clinicopathologic characteristics remain to be further elucidated, and prognostic factors are yet to be well established. With the aim of better characterizing this carcinoma and searching for prognostic indicators, we collected 62 ACCs and investigated the following parameters: site, size, local infiltration, node and distant metastases, architectural pattern, nuclear atypia, presence of necrosis, lymphovascular and perineural invasion, proliferation, BCL10, trypsin, carboxyl ester lipase, amylase, lipase, PDX1, cytokeratin 19 (CK19), CK7, p53, and ?-catenin expression. Twelve cases showing >30% of endocrine cells were reclassified as mixed acinar-neuroendocrine carcinomas, whereas 1 tumor was reclassified as a mixed ductal-acinar carcinoma and was excluded from the statistical prognostic evaluations. BCL10 and trypsin were the most reliable immunohistochemical markers, whereas amylase and lipase were not. Surgery was statistically correlated with a better prognosis (P=0.0008). Among resected tumors there was no difference in survival between ACCs and mixed acinar-neuroendocrine carcinomas, and factors that significantly correlated with poor prognosis were size >6.5 cm (P=0.004), lymph node (P=0.0039) and distant (P=0.008) metastases, and UICC stage (P=0.009). Stage was the only independent prognostic factor at multivariable analysis, and the best prognostic discrimination was observed on grouping together stages I and II and grouping together stages III and IV, suggesting a simplification of the UICC staging for such cancers. In addition, vascular and perineural invasion and CK19 and p53 expression showed a trend for poor prognosis, not reaching statistical significance. PMID:23026929

La Rosa, Stefano; Adsay, Volkan; Albarello, Luca; Asioli, Sofia; Casnedi, Selenia; Franzi, Francesca; Marando, Alessandro; Notohara, Kenji; Sessa, Fausto; Vanoli, Alessandro; Zhang, Lizhi; Capella, Carlo

2012-12-01

82

[Morphological and histological studies of Herba Boschniakiae].  

PubMed

This paper deals with the morphological characters of the plants and drugs, and the histological characters of the stems of Herba Boschniakiae (Boschniakia rossica). This results provide authentic methods for the identification of Herba Boschniakiae. PMID:12575046

Wang, B; Tu, P; Deng, X

1999-02-01

83

Probing Red Blood Cell Morphology Using High-Frequency Photoacoustics  

PubMed Central

A method that can rapidly quantify variations in the morphology of single red blood cells (RBCs) using light and sound is presented. When irradiated with a laser pulse, an RBC absorbs the optical energy and emits an ultrasonic pressure wave called a photoacoustic wave. The power spectrum of the resulting photoacoustic wave contains distinctive features that can be used to identify the RBC size and morphology. When particles 5–10 ?m in diameter (such as RBCs) are probed with high-frequency photoacoustics, unique periodically varying minima and maxima occur throughout the photoacoustic signal power spectrum at frequencies >100 MHz. The location and distance between spectral minima scale with the size and morphology of the RBC; these shifts can be used to quantify small changes in the morphology of RBCs. Morphological deviations from the normal biconcave RBC shape are commonly associated with disease or infection. Using a single wide-bandwidth transducer sensitive to frequencies between 100 and 500 MHz, we were able to differentiate healthy RBCs from irregularly shaped RBCs (such as echinocytes, spherocytes, and swollen RBCs) with high confidence using a sample size of just 21 RBCs. As each measurement takes only seconds, these methods could eventually be translated to an automated device for rapid characterization of RBC morphology and deployed in a clinical setting to help diagnose RBC pathology.

Strohm, Eric M.; Berndl, Elizabeth S.L.; Kolios, Michael C.

2013-01-01

84

Probing red blood cell morphology using high-frequency photoacoustics.  

PubMed

A method that can rapidly quantify variations in the morphology of single red blood cells (RBCs) using light and sound is presented. When irradiated with a laser pulse, an RBC absorbs the optical energy and emits an ultrasonic pressure wave called a photoacoustic wave. The power spectrum of the resulting photoacoustic wave contains distinctive features that can be used to identify the RBC size and morphology. When particles 5-10 ?m in diameter (such as RBCs) are probed with high-frequency photoacoustics, unique periodically varying minima and maxima occur throughout the photoacoustic signal power spectrum at frequencies >100 MHz. The location and distance between spectral minima scale with the size and morphology of the RBC; these shifts can be used to quantify small changes in the morphology of RBCs. Morphological deviations from the normal biconcave RBC shape are commonly associated with disease or infection. Using a single wide-bandwidth transducer sensitive to frequencies between 100 and 500 MHz, we were able to differentiate healthy RBCs from irregularly shaped RBCs (such as echinocytes, spherocytes, and swollen RBCs) with high confidence using a sample size of just 21 RBCs. As each measurement takes only seconds, these methods could eventually be translated to an automated device for rapid characterization of RBC morphology and deployed in a clinical setting to help diagnose RBC pathology. PMID:23823224

Strohm, Eric M; Berndl, Elizabeth S L; Kolios, Michael C

2013-07-01

85

CLONAL GROWTH IN VITRO OF HUMAN CELLS WITH FIBROBLASTIC MORPHOLOGY  

PubMed Central

A methodology has been described for reliable cultivation in vitro of dispersed fibroblastic cells obtained from normal human organs. The procedure has permitted establishment of stable cell lines from almost every sample taken, among which the following organs were represented: skin, spleen, amnion, lung, liver, bone marrow, brain, muscle, and heart. Equally good growth has been achieved with cells from embryonic or adult tissues. The methods previously developed whereby single cells plated in Petri dishes grow into isolated macroscopic colonies can successfully be applied to the plating of human fibroblastic stocks. Plating efficiencies in the neighborhood of 50 to 60 per cent are readily achieved with such strains. The resulting colonies can be picked and clonal stocks established. Fibroblastic morphology is maintained in the colonies arising from every single cell of such clonal stocks. All of the single cells from epithelioid clonal strains also maintain their integrity throughout repeated subculture. Since the difference between clonal stocks of these two types is always maintained whenever the respective single cells are plated in the same medium, regardless of the previous history of these stocks, it may be concluded that a true genetic difference exists in these cell lines. In addition to the morphological differences between epithelioid and fibroblastic cell strains, the latter have more demanding nutritional requirements for single cell growth. Thus, single cells of fibroblastic lines almost never produce colonies with high efficiency unless the growth medium which is sufficient for epithelioid cells is supplemented with embryo extract, or a cell feeder layer. Fibroblastic cells are also more resistant to tryptic digestion of the bond uniting the cells to glass surfaces. By use of differential media, growth of both fibroblastic and epithelioid cells, respectively, has been obtained, from dispersed single cells obtained by trypsinization of a specimen of human embryonic lung.

Puck, Theodore T.; Cieciura, Steven J.; Fisher, Harold W.

1957-01-01

86

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

87

[Morphology, cell-cell interactions, and migratory activity of IAR-2 epithelial cells transformed with the RAS oncogene: contribution of cell adhesion protein E-cadherin].  

PubMed

The destruction of stable cell-cell adhesion and the acquisition of the ability to migrate are consistent stages of neoplastic evolution of tumor cells of epithelial origin. We studied the morphologic and mi gration characteristics of epithelial cells of Iar1162 and IAR1170 clones derived from a mixed culture of on cogene N-RasV12-transformed cell line IAR-2. It was found that the mutant oncogene RAS can cause two types of morphological changes in IAR-2 epithelial cells. Cells of one type (IAR1162 clones) underwent epithelial-mesenchymal transition: they stopped to express E-cadherin, acquired fibroblast-like morphology, and did not form tight junctions. Cells of the other type (IAR1170 clones) retained a morphology close to the morphology of nontransformed progenitor cells, formed E-cadherin-based adherens junctions and tight junctions, and formed a monolayer in confluent culture. However, in both IAR1162 and IAR1170 cells, the mutant oncogene RAS caused the destruction of marginal actin bundle and the reorganization of cell-cell adherens junctions. RAS-transformed IAR1162 and IAR1170 epithelial cells acquired the ability to migrate on a flat substrate as well as through narrow pores in membranes of migration chambers. A videomicroscopic study of transformed epithelial cell cultures demonstrated the instability of cell-cell contacts and the independent nature of cell migration. IAR 1170 epithelial cells, which had E-cadherin-based adherens junctions, were also able to move as a group (collective migration). 1162D3 cells, which lost the ability to express endogenous E-cadherin as a result of Ras-transformation, were transfected with a plasmid carrying the CDH1. As a result of transfection, clones of cells with different levels of expression of exogenous E-cadherin were obtained. The high level of expression of exogenous E-cadherin in transformed epithelial cells led to a decrease in the rate of migration on a two-dimensional substrate of the cells that were in contact with neighboring cells but almost had no effect on the migration of single cells, at the same time increasing the number of cells that migrated through the pores in migration chambers. Thus, the destruction of marginal actin bundle and the change in the spatial organization of cell-cell adherens junctions, irrespective of the presence or absence of E-cadherin, was accompanied by destruction of stable cell-cell adhesion and the appearance of locomotor activity in Ras-transformed epithelial cells. The retaining of E-cadherin in cell-cell adhesion junctions affects the locomotor activity of transformed epithelial cells and plays an important role in their collective migration. PMID:22288108

Zhitniak, I Iu; Glushankova, N A

2011-01-01

88

Morphological studies of the vestibular nerve  

NASA Technical Reports Server (NTRS)

The anatomy of the intratemporal part of the vestibular nerve in man, and the possible age related degenerative changes in the nerve were studied. The form and structure of the vestibular ganglion was studied with the light microscope. A numerical analysis of the vestibular nerve, and caliber spectra of the myelinated fibers in the vestibular nerve branches were studied in individuals of varying ages. It was found that the peripheral endings of the vestibular nerve form a complicated pattern inside the vestibular sensory epithelia. A detailed description of the sensory cells and their surface organelles is included.

Bergstroem, B.

1973-01-01

89

Morphological characterization of a human glioma cell l ine.  

PubMed

A human malignant continuous cell line, named NG97, was recently established in our laboratory. This cell line has been serially subcultured over 100 times in standard culture media presenting no sign of cell senescence. The NG97 cell line has a doubling time of about 24 h. Immunocytochemical analysis of glial markers demonstrated that cells are positive for glial fibrillary acidic protein (GFAP) and S-100 protein, and negative for vimentin. Under phase-contrast microscope, cultures of NG97 showed cells with variable morphological features, such as small rounded cells, fusiform cells (fibroblastic-like cells), and dendritic-like cells. However, at confluence just small rounded and fusiform cells can be observed. At scanning electron microscopy (SEM) small rounded cells showed heterogeneous microextentions, including blebs and filopodia. Dendritic-like cells were flat and presented extensive prolongations, making several contacts with small rounded cells, while fusiform cells presented their surfaces dominated by microvilli.We believe that the knowledge about NG97 cell line may be useful for a deeper understanding of biological and immunological characteristics of gliomas. PMID:15885136

Machado, Camila Ml; Schenka, André; Vassallo, José; Tamashiro, Wirla Msc; Gonçalves, Estela M; Genari, Selma C; Verinaud, Liana

2005-05-10

90

Morphological characterization of a human glioma cell l ine  

PubMed Central

A human malignant continuous cell line, named NG97, was recently established in our laboratory. This cell line has been serially subcultured over 100 times in standard culture media presenting no sign of cell senescence. The NG97 cell line has a doubling time of about 24 h. Immunocytochemical analysis of glial markers demonstrated that cells are positive for glial fibrillary acidic protein (GFAP) and S-100 protein, and negative for vimentin. Under phase-contrast microscope, cultures of NG97 showed cells with variable morphological features, such as small rounded cells, fusiform cells (fibroblastic-like cells), and dendritic-like cells. However, at confluence just small rounded and fusiform cells can be observed. At scanning electron microscopy (SEM) small rounded cells showed heterogeneous microextentions, including blebs and filopodia. Dendritic-like cells were flat and presented extensive prolongations, making several contacts with small rounded cells, while fusiform cells presented their surfaces dominated by microvilli. We believe that the knowledge about NG97 cell line may be useful for a deeper understanding of biological and immunological characteristics of gliomas.

Machado, Camila ML; Schenka, Andre; Vassallo, Jose; Tamashiro, Wirla MSC; Goncalves, Estela M; Genari, Selma C; Verinaud, Liana

2005-01-01

91

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

92

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

93

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.

Xie, Wenhai; Wang, Hu; Wu, Ji

2014-01-01

94

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

PubMed

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

95

Perivascular Mural Cells of the Mouse Choroid Demonstrate Morphological Diversity That Is Correlated to Vasoregulatory Function  

PubMed Central

Objective Perivascular mural cells of the choroid have been implicated in physiological functioning as well as in retinal disease pathogenesis. However details regarding their form and function are not well understood. We aim to characterize choroidal mural cells in the adult mouse choroid in terms of their distribution and morphology, and correlate these to their contractile behavior. Methods Sclerochoroidal flat-mounted explants were prepared from albino transgenic mice in which the ?-smooth muscle actin (?-SMA) promoter drives the expression of green fluorescent protein (GFP). ?-SMA-expressing smooth muscle cells and pericytes in the living choroid were thereby rendered fluorescent and imaged with confocal microscopy and live-cell imaging in situ. Results Choroidal perivascular mural cells demonstrate significant diversity in terms of their distribution and morphology at different levels of the vasculature. They range from densely-packed circumferentially-oriented cells that provide complete vascular coverage in primary arteries to widely-spaced stellate-shaped cells that are distributed sparsely over terminal arterioles. Mural cells at each level are immunopositive for contractile proteins ?-SMA and desmin and demonstrate vasoconstrictory contractile movements in response to endothelin-1 and the calcium ionophore, A23187, and vasodilation in response to the calcium chelator, BAPTA. The prominence of vasoregulatory contractile responses varies with mural cell morphology and density, and is greater in vessels with dense coverage of mural cells with circumferential cellular morphologies. In the choriocapillaris, pericytes demonstrate a sparse, horizontal distribution and are selectively distributed only to the scleral surface of the choriocapillaris. Conclusions Diversity and regional specialization of perivascular mural cells may subserve varying requirements for vasoregulation in the choroid. The model of the ?-SMA-GFP transgenic albino mouse provides a useful and intact system for the morphological and functional study of choroidal mural cells.

Condren, Audrey B.; Kumar, Anil; Mettu, Pradeep; Liang, Katharine J.; Zhao, Lian; Tsai, Jen-yue; Fariss, Robert N.; Wong, Wai T.

2013-01-01

96

Controlling Active Layer Morphology in Polymer/Fullerene Solar Cells  

NASA Astrophysics Data System (ADS)

The active layer in most polymer solar cells is based on the bulk heterojunction (BHJ) design. BHJs are prepared by arresting the phase separation of a polymer/fullerene blend to produce a nanoscale, interpenetrating network. Such non-equilibrium structures are very difficult to control and reproduce, posing a significant challenge for fundamental structure-property investigations. We demonstrate a new approach to control the active layer morphology with a simple two-step process: First, a thin film of poly(3-hexylthiophene) (P3HT) is cross-linked into stable nanostructures or microstructures with electron-beam lithography [1]. Second, a soluble fullerene is spun-cast on top of the patterned polymer to complete the heterojunction. Significantly, irradiated P3HT films retain good optoelectronic properties and bilayer P3HT/fullerene heterojunctions yield power-conversion efficiencies near 0.5%. We have performed preliminary studies with model nanostructured devices and we find that efficiency increases with interfacial area [2]. These model devices are very valuable for fundamental studies because the interfacial area is accurately measured with small-angle X-ray scattering, and the active layer can be ``deconstructed'' for imaging with atomic force microscopy. [4pt] [1] S. Holdcroft, Adv. Mater. 2001, 13, 1753-1765.[0pt] [2] He et al., Adv Funct. Mater. 2011, 21, 139-146.

Moungthai, Suchanun; Mahadevapuram, Nikhila; Stein, Gila

2012-02-01

97

Quantitative methods to characterize morphological properties of cell lines.  

PubMed

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

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

2012-07-01

98

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

99

Morphologic characteristics of blastic plasmacytoid dendritic cell neoplasm: a case report.  

PubMed

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare aggressive lymphoma derived from plasmacytoid dendritic cells or precursor dendritic cells. Despite some 240 reported cases, its morphology and especially ultrastructure has not been satisfactorily studied. A case is reported of a 13 year old boy, who, despite chemotherapy, died within a 12-month period. The electron microscopy findings - microvillous processes, nuclei with slight irregularities, a moderate amount of heterochromatin, and rough endoplasmic reticulum in the form of long, narrow profiles, often in parallel arrangements - taken together, serve to distinguish BPDCN from other neoplastic cells, such as monocytes, plasma cells and the cells of chronic lymphocyte leukemia. PMID:23957370

Ru, Yongxin; Zhang, Peihong; Dong, Shuxu; Wang, Huijun; Zhao, Shixuan; Mi, Yingchang; Eyden, Brian

2014-02-01

100

[Vestibular compensation studies]. [Vestibular Compensation and Morphological Studies  

NASA Technical Reports Server (NTRS)

The following topics are reported: neurophysiological studies on MVN neurons during vestibular compensation; effects of spinal cord lesions on VNC neurons during compensation; a closed-loop vestibular compensation model for horizontally canal-related MVN neurons; spatiotemporal convergence in VNC neurons; contributions of irregularly firing vestibular afferents to linear and angular VOR's; application to flight studies; metabolic measures in vestibular neurons; immediate early gene expression following vestibular stimulation; morphological studies on primary afferents, central vestibular pathways, vestibular efferent projection to the vestibular end organs, and three-dimensional morphometry and imaging.

Perachio, Adrian A. (Principal Investigator)

1996-01-01

101

Inflammatory cytokines induce a reduction in E-cadherin expression and morphological changes in MDCK cells.  

PubMed

Epithelial-mesenchymal transition (EMT) is a fundamental phenomenon in organisms that occurs during gastrulation, wound healing, and cancer metastasis. Various cytokines induce EMT processes through complex mechanisms. Inflammatory cytokines, such as tumor necrosis factor alpha (TNF-?) and interleukin 6 (IL-6), induce EMT in human cell lines. However, whether inflammatory cytokines can affect EMT processes in canine cell lines remains unclear. In this study, we investigated the role of transforming growth factor beta (TGF-?), TNF-?, and IL-6 in Madin-Darby canine kidney (MDCK) cells. We found that the localization of E-cadherin, a cell adhesion molecule, was shifted and that its expression was decreased. We also observed morphological changes in MDCK cells under persistent stimulation of inflammatory cytokines. Morphological changes in cells may occur during late stages of EMT processes; inflammatory cytokines may be important in these changes. PMID:24565002

Saito, Tomochika; Yoshida, Kota; Matsumoto, Kaori; Saeki, Kohei; Tanaka, Yuiko; Ong, Siew-Mei; Sasaki, Nobuo; Nishimura, Ryohei; Nakagawa, Takayuki

2014-04-01

102

Spermatogenic cells of the prepuberal mouse: isolation and morphological characterization  

PubMed Central

A procedure is described which permits the isolation from the prepuberal mouse testis of highly purified populations of primitive type A spermatogonia, type A spermatogonia, type B spermatogonia, preleptotene primary spermatocytes, leptotene and zygotene primary spermatocytes, pachytene primary spermatocytes and Sertoli cells. The successful isolation of these prepuberal cell types was accomplished by: (a) defining distinctive morphological characteristics of the cells, (b) determining the temporal appearance of spermatogenic cells during prepuberal development, (c) isolating purified seminiferous cords, after dissociation of the testis with collagenase, (d) separating the trypsin-dispersed seminiferous cells by sedimentation velocity at unit gravity, and (e) assessing the identity and purity of the isolated cell types by microscopy. The seminiferous epithelium from day 6 animals contains only primitive type A spermatogonia and Sertoli cells. Type A and type B spermatogonia are present by day 8. At day 10, meiotic prophase is initiated, with the germ cells reaching the early and late pachytene stages by 14 and 18, respectively. Secondary spermatocytes and haploid spermatids appear throughout this developmental period. The purity and optimum day for the recovery of specific cell types are as follows: day 6, Sertoli cells (purity>99 percent) and primitive type A spermatogonia (90 percent); day 8, type A spermatogonia (91 percent) and type B spermatogonia (76 percent); day 18, preleptotene spermatocytes (93 percent), leptotene/zygotene spermatocytes (52 percent), and pachytene spermatocytes (89 percent), leptotene/zygotene spermatocytes (52 percent), and pachytene spermatocytes (89 percent).

Bellve, AR; Cavicchia, JC; Millette, CF; O'Brien, DA; Bhatnagar, YM; Dym, M

1977-01-01

103

Morphology and photoluminescence study of titania nanoparticles  

Microsoft Academic Search

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\\u000a acid, titanium tetraisopropoxide, and triblock copolymer—are varied to investigate their effect on the resulting titania morphology.\\u000a An increased titania precursor or polymer content yields smaller primary titania structures. Microbeam grazing incidence small-angle

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

2011-01-01

104

Morphologic study of the Glenoid in primary glenohumeral osteoarthritis  

Microsoft Academic Search

We studied the natural course and the possibility of making a prognostic classification of glenoid morphology in primary glenohumeral osteoarthritis (GHOA). For this purpose, serial computed tomography scans of 113 osteoarthritic shoulders were reviewed. The position of the humeral head with respect to the glenoid seems to be an important predictor of the glenoid morphologic evolution. Three main glenoid types

Gilles Walch; Roger Badet; Aziz Boulahia; Alfred Khoury

1999-01-01

105

ACME: automated cell morphology extractor for comprehensive reconstruction of cell membranes.  

PubMed

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

106

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).

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

2012-01-01

107

The effect of silica nanoparticle-modified surfaces on cell morphology, cytoskeletal organization and function  

PubMed Central

Chemical and morphological characteristics of a biomaterial surface are thought to play an important role in determining cellular differentiation and apoptosis. In this report, we investigate the effect of nanoparticle (NP) assemblies arranged on a flat substrate on cytoskeletal organization, proliferation and metabolic activity on two cell types, Bovine aortic endothelial cells (BAECs) and mouse calvarial preosteoblasts (MC3T3-E1). To vary roughness without altering chemistry, glass substrates were coated with monodispersed silica nanoparticles of 50, 100 and 300 nm in diameter. The impact of surface roughness at the nanoscale on cell morphology was studied by quantifying cell spreading, shape, cytoskeletal F-actin alignment, and recruitment of focal adhesion complexes (FAC) using image analysis. Metabolic activity was followed using a thiazolyl blue tetrazolium bromide assay. In the two cell types tested, surface roughness introduced by nanoparticles had cell type specific effects on cell morphology and metabolism. While BAEC on NP-modified substrates exhibited smaller cell areas and fewer focal adhesion complexes compared to BAEC grown on glass, MC3T3-E1 cells in contrast exhibited larger cell areas on NP-modified surfaces and an increased number of FACs, in comparison to unmodified glass. However, both cell types on 50 nm NP had the highest proliferation rates (comparable to glass control) whereas cells grown on 300 nm NP exhibited inhibited proliferation. Interestingly, for both cell types surface roughness promoted the formation of long, thick F-actin fibers, which aligned with the long axis of each cell. These findings are consistent with our earlier result that osteogenic differentiation of human mesenchymal progenitor cells is enhanced on NP-modified surfaces. Our finding that nanoroughness, as imparted by nanoparticle assemblies, effects cellular processes in a cell specific manner, can have far reaching consequences on the development of “smart” biomaterials especially for directing stem cell differentiation.

Lipski, Anna M.; Pino, Christopher J.; Haselton, Frederick R.; Chen, I.-Wei; Shastri, V. Prasad

2010-01-01

108

Cell morphology, proliferation and collagen synthesis of human fibroblasts cultured on sepiolite-collagen complexes.  

PubMed

The growth and morphology as well as collagen biosynthesis of human fibroblasts obtained and cultured on sepiolite-collagen complexes have been studied. No differences on cell morphology and growth properties nor collagen synthesis were observed when compared with standard culture substrates. The type I/type III ratio of biosynthesized collagen by fibroblasts cultured on sepiolite-collagen complexes was about 5-6 with no difference when compared to control conditions. This normal behavior was also observed for the type I/type III procollagens. According to these studies the sepiolite-collagen complexes do not modify the studied features of the fibroblasts. PMID:2967297

Olmo, N; Lizarbe, M A; Turnay, J; Müller, K P; Gavilanes, J G

1988-04-01

109

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

110

A screening approach reveals the influence of mineral coating morphology on human mesenchymal stem cell differentiation  

PubMed Central

“Biomimetic” inorganic coating on biomaterials has been an active area of research with the intention of providing bioactive surfaces that can regulate cell behavior. Previous studies have demonstrated that human mesenchymal stem cell (hMSC) behavior is differentially regulated by physical and chemical properties of inorganic mineral coatings, indicating that modulation of mineral properties has potential importance in regulating hMSC behavior. However, the lack of an efficient experimental context in which to study stem cell behavior on inorganic substrates has made it difficult to systematically study the effects of specific mineral coating parameters on hMSC behavior. In this study, we developed an efficient experimental platform to screen for the effects of mineral coating morphology on hMSC expansion and differentiation. hMSC expansion on mineral coatings was regulated by micro-scale morphology of mineral coatings, with greater expansion on small granule-like coatings when compared to plate-like or net-like coatings. In contrast, hMSC osteogenic differentiation was inversely correlated with cell expansion on mineral coating, indicating that mineral coating morphology was a key parameter regulating hMSC differentiation. The effect of mineral coating morphology on hMSC behavior suggests the utility of this inorganic screening platform to identify optimal coatings for medical devices and bone tissue engineering applications.

Choi, Siyoung; Murphy, William L.

2013-01-01

111

Adult renal cell carcinoma with rhabdoid morphology represents a neoplastic dedifferentiation analogous to sarcomatoid carcinoma  

Microsoft Academic Search

Renal cell carcinoma (RCC) with rhabdoid morphology (RCC-RM) is a recently described variant of RCC, which has an aggressive biologic behavior and poor prognosis, akin to sarcomatoid RCC. The current World Health Organization classification of RCC does not include the rhabdoid phenotype as a distinct histologic entity. The aim of this study is to investigate whether RCC-RM represents a dedifferentiation

Jennifer R. Chapman-Fredricks; Loren Herrera; Jorge Bracho; Carmen Gomez-Fernandez; Raymond Leveillee; Luis Rey; Merce Jorda

2011-01-01

112

Craniofacial morphology in patients with sickle cell disease: a cephalometric analysis  

Microsoft Academic Search

SUMMARY The aim of the study was to evaluate the craniofacial morphology in Caucasian patients with sickle cell disease (SCD) by comparing them with a healthy group paired for gender and age, by means of lateral cephalometric radiographs. Thirty-six Sicilian patients with SCD (17 females and 19 males), including 14 b s ? s (mean age 28 ± 5.9 years),

Valeria Licciardello; Gregoria Bertuna; Piera Samperi

2007-01-01

113

Adult renal cell carcinoma with rhabdoid morphology represents a neoplastic dedifferentiation analogous to sarcomatoid carcinoma.  

PubMed

Renal cell carcinoma (RCC) with rhabdoid morphology (RCC-RM) is a recently described variant of RCC, which has an aggressive biologic behavior and poor prognosis, akin to sarcomatoid RCC. The current World Health Organization classification of RCC does not include the rhabdoid phenotype as a distinct histologic entity. The aim of this study is to investigate whether RCC-RM represents a dedifferentiation of a classifiable-type World Health Organization RCC or a carcinosarcoma with muscle differentiation. We reviewed 168 cases of RCC obtained between 2003 and 2008. From these cases, 10 (6%) were found to have areas of classic rhabdoid morphology. Immunohistochemistry for cytokeratin, epithelial membrane antigen, desmin, CD10, and CD117 was performed in each case using the labeled streptavidin-biotin method. Rhabdoid differentiation was identified in association with conventional-type RCC (9) and with unclassifiable-type RCC with spindle cell morphology (1). In all cases, both the rhabdoid and nonrhabdoid tumoral areas were positive for cytokeratin and epithelial membrane antigen and negative for desmin. Cytokeratin positivity in the rhabdoid areas was focal. In cases associated with conventional-type RCC, CD10 was positive in both the rhabdoid and nonrhabdoid foci. CD117 was negative in these tumors. The unclassifiable-type RCC with spindle cell morphology was negative for both CD10 and CD117. The similar immunophenotype between the rhabdoid and nonrhabdoid tumoral foci supports the origin of the rhabdoid cells from the classifiable-type RCC. Areas of rhabdoid morphology do not represent muscle metaplastic differentiation. Renal cell carcinoma with rhabdoid morphology may represent a dedifferentiation of a classifiable-type RCC, similar to that of sarcomatoid differentiation. The recognition of RCC-RM is important as it allows for the inclusion of these high-grade malignancies into a category associated with poor prognosis despite lacking the spindle cell component classically identified as sarcomatoid change. PMID:21665507

Chapman-Fredricks, Jennifer R; Herrera, Loren; Bracho, Jorge; Gomez-Fernandez, Carmen; Leveillee, Raymond; Rey, Luis; Jorda, Merce

2011-10-01

114

Hyperthermia effects on the cytoskeleton and on cell morphology.  

PubMed

Human erythrocyte ghost membranes undergo five thermal transitions at temperatures between 50 and 75 degrees C. Spontaneous fragmentation of whole cells occurs at 50 degrees C, a transition temperature which has been associated with denaturation of the cytoskeletal protein spectrin. Haemolysis occurs at 65 degrees C and microvesiculation of the resulting ghost membrane is seen at temperatures in excess of 70 degrees C. The cell fragmentation develops through spatially periodic growth of surface waves on the erythrocyte membrane. The interfacial instability associated with the surface wave growth arises from thermal impairment of the stabilizing function of spectrin. Interfacial instability is also associated with the beading pattern which arises when long processes drawn mechanically from erythrocytes are heated. Similar beading of cell processes is a feature of many cytoskeleton-weakening agents acting on nonerythroid cells. The complexities of the cytoskeletons of eucaryotic cells including structure, composition and interaction of cytoskeletal microfilaments, microtubules and intermediate filaments, both with each other and with the cell membrane, are outlined. Attention is drawn to the importance of the function of proteins which interact with the cytoskeletal elements and to the influence of calcium concentration on those proteins. Actin monomers are denatured (and are no longer polymerizable) at temperatures a few degrees above the growth temperature of the cell source of the actins. Actin in the filament form requires much higher denaturation temperatures. This greater thermal lability of actin monomers would be expected to result (because of treadmilling in microfilaments) in a gradual depolymerization of the filaments. Depolymerization of microtubules occurs at temperatures close to the cell growth temperature and may be dependent on a thermal effect on microtubule-associated proteins. The response of spread interphase mammalian cells to temperatures around 43 degrees C includes central retraction of membrane, loss of microvilli, concentration of organelles in a juxtanuclear position, rounding up of the cell, retention of contact with the substratum by processes which are sometimes beaded and blebbing of the cell membrane. The morphological effects of heat are compared here with those of cytochalasin, colcemid and a number of morphology modifying agents. Blebbing of membrane is a fairly general response of cells to stress. Proteins in blebs diffuse as if released from a lateral constraint. Moderate heating has been shown to cause cortical microfilament separation from the plasma membrane.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:3332484

Coakley, W T

1987-01-01

115

Neutral Density Cells in the High-Latitude Thermosphere: Morphology, Data Analysis, and Mechanisms.  

NASA Astrophysics Data System (ADS)

The lower thermosphere is a region of the atmosphere which has not been fully explored. A new high latitude structure has been discovered in simulations of the lower thermospheric neutral density at altitudes from 120-300 km. The National Center for Atmospheric Research (NCAR) -Thermosphere/Ionosphere General Circulation Model (TIGCM) predicts mesoscale cellular structures with density variations from cell to cell of nearly 50% during magnetically active conditions. Using these simulations, a density cell morphology is defined as a function of altitude, magnetic activity, season, and solar cycle. For example, at 200 km under magnetically active conditions, the density structure consists of low density cells near dawn and dusk and high density cells near noon and midnight. The cell morphology provides a new framework in which to interpret lower thermospheric density data. Data to test and confirm the model predictions were provided by the SETA-1 satellite which flew in almost circular sun -synchronous orbits near 200 km altitudes. The cell morphology also provides a framework in which to analyze the mechanisms causing the density cells. The mechanisms consist of a combination of high latitude forcing and heating and dynamic meteorology effects. The development of the cell morphology, the evidence that they exist in the data, and the determination of the causal mechanisms show that the high latitude density cells are a structured variation in the neutral mass density rather than a transient phenomenon. The analysis of the density cells is of vital importance to studies of the lower thermosphere. It provides a new understanding of lower thermospheric dynamics and a new theoretical framework for the analysis and interpretation of density data from both past and future experiments.

Schoendorf, J.

116

Morphological homogeneity of neurons: searching for outlier neuronal cells.  

PubMed

We report a morphology-based approach for the automatic identification of outlier neurons, as well as its application to the NeuroMorpho.org database, with more than 5,000 neurons. Each neuron in a given analysis is represented by a feature vector composed of 20 measurements, which are then projected into a two-dimensional space by applying principal component analysis. Bivariate kernel density estimation is then used to obtain the probability distribution for the group of cells, so that the cells with highest probabilities are understood as archetypes while those with the smallest probabilities are classified as outliers. The potential of the methodology is illustrated in several cases involving uniform cell types as well as cell types for specific animal species. The results provide insights regarding the distribution of cells, yielding single and multi-variate clusters, and they suggest that outlier cells tend to be more planar and tortuous. The proposed methodology can be used in several situations involving one or more categories of cells, as well as for detection of new categories and possible artifacts. PMID:22615032

Zawadzki, Krissia; Feenders, Christoph; Viana, Matheus P; Kaiser, Marcus; Costa, Luciano da F

2012-10-01

117

Csk differentially regulates Src64 during distinct morphological events in Drosophila germ cells.  

PubMed

The Src family protein tyrosine kinases (SFKs) are crucial regulators of cellular morphology. In Drosophila, Src64 controls complex morphological events that occur during oogenesis. Recent studies have identified key Src64-dependent mechanisms that regulate actin cytoskeletal dynamics during the growth of actin-rich ring canals, which act as intercellular bridges between germ cells. By contrast, the molecular mechanisms that regulate Src64 activity levels and potential roles for Src64 in additional morphological events in the ovary have not been defined. In this report, we demonstrate that regulation of Src64 by Drosophila C-terminal-Src Kinase (Csk) contributes to the packaging of germline cysts by overlying somatic follicle cells during egg chamber formation. These results uncover novel roles for both Csk and Src64 in a dynamic event that involves adhesion, communication between cell types and control of cell motility. Strikingly, Src64 and Csk function in the germline to control packaging, not in migrating follicle cells, suggesting novel functions for this signaling cassette in regulating dynamic adhesion. In contrast to the role played by Csk in the regulation of Src64 activity during packaging, Csk is dispensable for ring canal growth control, indicating that distinct mechanisms control Src64 activity during different morphological events. PMID:16775001

O'Reilly, Alana M; Ballew, Anna C; Miyazawa, Byron; Stocker, Hugo; Hafen, Ernst; Simon, Michael A

2006-07-01

118

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

119

Fetal GM1-gangliosidosis: morphological and biochemical studies.  

PubMed

A 23-week fetus with GM1-gangliosidosis type 1 was studied morphologically and biochemically. The GM1-ganglioside content in the brain was approximately twice that of a control. A GM1-ganglioside comprised about 25% of the total ganglioside NANA (N-acetyl-neuraminic acid), whereas in control fetus brain the proportion was 14.3%. The storage of GM1-ganglioside in fetal GM1-ganglioside brain was confirmed by a thin-layer chromatogram immunostained with anti-GM1-ganglioside antibody. The accumulation of GM1-ganglioside in visceral organs (liver, spleen and kidney) was not detected with biochemical and immunochemical methods. However, in hepatocytes, Kupffer cells, renal tubular cells and spleen cells from the affected fetus, there were many vacuoles which could contain oligosaccharides as storage materials. These data suggest that pathochemical changes in the brain and visceral organs of an affected fetus are already evident in the second trimester of the pregnancy. Tissue specific accumulation of glycolipids or oligosaccharides in fetal GM1-gangliosidosis suggests that the biosynthesis or degradation of these compounds occurs at different periods. PMID:2618963

Ida, H; Eto, Y; Maekawa, K

1989-01-01

120

Experimental Study of the Morphology and Dynamics of Gas-Laden Layers Under the Anodes in an Air-Water Model of Aluminum Reduction Cells  

NASA Astrophysics Data System (ADS)

The bubble layer formed under an anode and the bubble-induced flow play a significant role in the aluminum electrolysis process. The bubbles covering the anode bottom reduce the efficient surface that can carry current. In our experiments, we filmed and studied the bubble layer under the anode in a real-size air-water electrolysis cell model. Three different flow regimes were found depending on the gas generation rate. The covering factor was found to be proportional to the gas generation rate and inversely proportional to the angle of inclination. A correlation between the average height of the entire bubble layer and the position under the anode was determined. From this correlation and the measured contact sizes, the volume of the accumulated gas was calculated. The sweeping effect of large bubbles was observed. Moreover, the small bubbles under the inner edge of the anode were observed to move backward as a result of the escape of huge gas pockets, which means large momentum transport occurs in the bath.

Vékony, Klára; Kiss, László I.

2012-10-01

121

Surface Morphological Studies on Cupric Oxide Thin Films  

NASA Astrophysics Data System (ADS)

Polycrystalline cupric oxide (CuO) thin films were deposited using alkaline solution bath employing cathodic electrodeposition method. The thin films were electrodeposited at various solution pH. The surface morphology and elemental analyzes of the films were studied using scanning electron microscopy and energy dispersive X-ray analysis (EDX), respectively. SEM studies revealed that the surface morphology could be tailored suitably by adjusting the pH value during deposition.

Mahalingam, T.; Dhanasekaran, V.; Ravi, G.; Vidhya, M. Sangeetha; Sasikumar, T.; Joycee, P.

2011-07-01

122

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. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 977-987, 2014. PMID:24259351

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

2014-07-01

123

Filopodial morphology correlates to the capture efficiency of primary T-cells on nanohole arrays.  

PubMed

Nanostructured surfaces emerge as a new class of material for capture and separation of cell populations including primary immune cells and disseminating rare tumor cells, but the underlying mechanism remains elusive. Although it has been speculated that nanoscale topological structures on cell surface are involved in the cell capture process, there are no studies that systematically analyze the relation between cell surface structures and the capture efficiency. Here we report on the first mechanistic study by quantifying the morphological parameters of cell surface nanoprotrusions, including filopodia, lamellipodia, and microvilli in the early stage of cell capture (< 20 min) in correlation to the efficiency of separating primary T lymphocytes. This was conducted by using a set of nanohole arrays (NHAs) with varying hole and pitch sizes. Our results showed that the formation of filopodia (e.g., width of filopodia and the average number of the filopodial filaments per cell) depends on the feature size of the nanostructures and the cell separation efficiency is strongly correlated to the number of filopodial fibers, suggesting a possible role of early stage mechanosensing and cell spreading in determining the efficiency of cell capture. In contrast, the length of filopodial filaments was less significantly correlated to the cell capture efficiency and the nanostructure dimensions of the NHAs. This is the first mechanistic study on nanostructure-based immune cell capture and provides new insights to not only the biology of cell-nanomaterial interaction but also the design of new rare cell capture technologies with improved efficiency and specificity. PMID:24749397

Kim, Dong-Joo; Kim, Gil-Sung; Seol, Jin-Kyeong; Hyung, Jung-Hwan; Park, No-Won; Lee, Mi-Ri; Lee, Myung Kyu; Fan, Rong; Lee, Sang-Kwon

2014-06-01

124

Deficiency of Cardiolipin Synthase Causes Abnormal Mitochondrial Function and Morphology in Germ Cells of Caenorhabditis elegans*  

PubMed Central

Cardiolipin (CL) is a major membrane phospholipid specifically localized in mitochondria. At the cellular level, CL has been shown to have a role in mitochondrial energy production, mitochondrial membrane dynamics, and the triggering of apoptosis. However, the in vivo role of CL in multicellular organisms is largely unknown. In this study, by analyzing deletion mutants of a CL synthase gene (crls-1) in Caenorhabditis elegans, we demonstrated that CL depletion selectively caused abnormal mitochondrial function and morphology in germ cells but not in somatic cell types such as muscle cells. crls-1 mutants reached adulthood but were sterile with reduced germ cell proliferation and impaired oogenesis. In the gonad of crls-1 mutants, mitochondrial membrane potential was significantly decreased, and the structure of the mitochondrial cristae was disrupted. Contrary to the abnormalities in the gonad, somatic tissues in crls-1 mutants appeared normal with respect to cell proliferation, mitochondrial function, and mitochondrial morphology. Increased susceptibility to CL depletion in germ cells was also observed in mutants of phosphatidylglycerophosphate synthase, an enzyme responsible for producing phosphatidylglycerol, a precursor phospholipid of CL. We propose that the contribution of CL to mitochondrial function and morphology is different among the cell types in C. elegans.

Sakamoto, Taro; Inoue, Takao; Otomo, Yukae; Yokomori, Nagaharu; Ohno, Motoki; Arai, Hiroyuki; Nakagawa, Yasuhito

2012-01-01

125

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

126

Changes in cell morphology due to plasma membrane wounding by acoustic cavitation  

PubMed Central

Acoustic cavitation-mediated wounding (i.e., sonoporation) has great potential to improve medical and laboratory applications requiring intracellular uptake of exogenous molecules; however, the field lacks detailed understanding of cavitation-induced morphological changes in cells and their relative importance. Here, we present an in-depth study of the effects of acoustic cavitation on cells using electron and confocal microscopy coupled with quantitative flow cytometry. High resolution images of treated cells show that morphologically different types of blebs can occur after wounding conditions caused by ultrasound exposure as well as by mechanical shear and strong laser ablation. In addition, these treatments caused wound-induced non-lytic necrotic death resulting in cell bodies we call wound-derived perikarya (WD-P). However, only cells exposed to acoustic cavitation experienced ejection of intact nuclei and nearly instant lytic necrosis. Quantitative analysis by flow cytometry indicates that wound-derived perikarya are the dominant morphology of nonviable cells, except at the strongest wounding conditions, where nuclear ejection accounts for a significant portion of cell death after ultrasound exposure.

Schlicher, Robyn K.; Hutcheson, Joshua D.; Radhakrishna, Harish; Apkarian, Robert P.; Prausnitz, Mark R.

2010-01-01

127

Biphasic alveolosquamoid renal carcinoma: a histomorphological, immunohistochemical, molecular genetic, and ultrastructural study of a distinctive morphologic variant of renal cell carcinoma.  

PubMed

Only a few cases of sarcomatoid renal cell carcinomas (RCCs) with squamous differentiation have been published. We present 2 RCCs exhibiting a hitherto not reported biphasic neoplastic cell population exhibiting a predominantly alveolar architecture where squamoid differentiation was identified in one of the neoplastic cell populations. None of the tumors showed chromophobe features or any evidence of sarcomatoid transformation. The tumors arose in 2 adult patients and were characterized by routine histology, immunohistochemistry, ultrastructure, array comparative genomic hybridization, confirmatory fluorescent in situ hybridization, and loss of heterozygosity analysis. Tumors measured 3 and 4 cm and were located within the renal parenchyma and had no pelvicalyceal connection. Both tumors were composed of a distinctly dual-cell population. The larger tumor cells displayed squamoid features and formed round well-demarcated solid alveolated islands that, in large parts, were surrounded by a smaller neoplastic cell component. The squamoid cells were immunoreactive for cytokeratins (CKs) (AE1-AE3, Cam 5.2, CK5/6, CK7, and CK20), epithelial membrane antigen, racemase/AMACR, and carboanhydrase IX (in 1 case focally). The small cell population was positive for CK7, epithelial membrane antigen, and racemase/AMACR, whereas CK20, AE1-3, and carboanhydrase IX were negative. CD10 was focally positive in the large squamoid cells in 1 case. Cathepsin K, E-cadherin, and CD117 displayed focal positivity in 1 case. Vimentin, RCC marker, parvalbumin, S100 protein, S100 A1, p63, p53, CDX2, uroplakin III, HMB45, TFE3, WT1, synaptophysin, chromogranin A, thyroglobulin, and TTF1 were negative. The proliferative activity (Ki-67) was low (1%) in the small cell component in both cases, whereas the large neoplastic tumor cells displayed a significantly higher proliferation (20%-35%). Ultrastructurally, desmosomes and tonofilaments were identified in the large tumor cells, confirming squamoid differentiation in a subset of tumor cells. Array comparative genomic hybridization of 1 analyzable case (confirmed with fluorescent in situ hybridization and loss of heterozygosity analysis) revealed partial or complete losses of chromosomes 2, 5, 6, 9, 12, 15, 16, 17, 18 and 22, (including biallelic loss of CDKN2A locus) and partial gains of chromosomes 1, 5, 11, 12 and 13. Follow-up at 6 years showed no recurrence or metastasis in 1 patient. The other (male) patients had a subcutaneous metastasis at presentation, but during a 1-year follow-up no evidence of recurrence or further metastatic events have been documented. Our data indicate that biphasic alveolosquamoid renal carcinoma is a unique and distinctive tumor. The large squamoid and small tumor cells have overlapping but still distinctive immunohistochemical patterns of protein expression. Multiple chromosomal aberrations were identified, some of them located in regions with known tumor suppressor genes and oncogenes. PMID:23036259

Petersson, Fredrik; Bulimbasic, Stela; Hes, Ondrej; Slavik, Pavol; Martínek, Petr; Michal, Michal; Gomol?áková, Barbora; Hora, Milan; Damjanov, Ivan

2012-12-01

128

Transmission Electron Microscopy Reveals Distinct Macrophage- and Tick Cell-Specific Morphological Stages of Ehrlichia chaffeensis  

PubMed Central

Background Ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis. Despite the induction of an active host immune response, the pathogen has evolved to persist in its vertebrate and tick hosts. Understanding how the organism progresses in tick and vertebrate host cells is critical in identifying effective strategies to block the pathogen transmission. Our recent molecular and proteomic studies revealed differences in numerous expressed proteins of the organism during its growth in different host environments. Methodology/Principal Findings Transmission electron microscopy analysis was performed to assess morphological changes in the bacterium within macrophages and tick cells. The stages of pathogen progression observed included the attachment of the organism to the host cells, its engulfment and replication within a morulae by binary fission and release of the organisms from infected host cells by complete host cell lysis or by exocytosis. E. chaffeensis grown in tick cells was highly pleomorphic and appears to replicate by both binary fission and filamentous type cell divisions. The presence of Ehrlichia-like inclusions was also observed within the nucleus of both macrophages and tick cells. This observation was confirmed by confocal microscopy and immunoblot analysis. Conclusions/Significance Morphological differences in the pathogen’s progression, replication, and processing within macrophages and tick cells provide further evidence that E. chaffeensis employs unique host-cell specific strategies in support of adaptation to vertebrate and tick cell environments.

Dedonder, Sarah E.; Cheng, Chuanmin; Willard, Lloyd H.; Boyle, Daniel L.; Ganta, Roman R.

2012-01-01

129

[Mesenchymal chondrosarcoma (clinico-morphological study)].  

PubMed

Mesenchymal chondrosarcoma was found in 11 out of 161 patients with chondrosarcoma of the bone. The assaultive nature of the disease is illustrated by the following data: the period between the manifestation of symptoms and the first visit to the doctor was 5.9 +/- 4.3 months; metastases were detected within 20.56 +/- 6.04 months and 8 patients out of 10 died within the first 5 years. Two histological structures were observed: those of the chondrosarcoma type and hemangiopericytoma-like structures formed of small atypical cells. PMID:6636625

Solov'ev, Iu N; Eremina, L A; Petrovichev, N N; Khmelev, O N; Kasumov, I V

1983-01-01

130

PVC\\/ABS Blends: Thermal and Morphological Studies  

Microsoft Academic Search

Poly(vinyl chloride) and acrylonitrile?butadiene?styrene terpolymer blends made via melt blending were studied with respect to property enhancement, morphology, and physicochemical characterization. Blends were characterized by various thermal, morphological, and spectro?chemical methods of analysis. Two distinct glass transitions were recorded by differential scanning calorimetry. This suggested the need for a compatibilizer. Thermal decomposition behavior of blends was analysed by thermogravimetric analysis.

Amit R. Gawade; A. V. Lodha; P. S. Joshi

2007-01-01

131

Functional morphology of the light yellow cell and yellow cell (sodium influx-stimulating peptide) neuroendocrine systems of the pond snail Lymnaea stagnalis  

Microsoft Academic Search

Neuroendocrine light yellow cells of the pond snail Lymnaea stagnalis express a neuropeptide gene encoding three different peptides. The morphology of the cell system has been studied by in situ hybridization, using two synthetic oligonucleotides encoding parts of light yellow cell peptides I and III, and by immunocytochemistry with antisera to synthetic light yellow cell peptide II and to two

H. H. Boer; Cora Montagne-Wajer; F. G. Smith; D. C. Parish; Marja D. Ramkema; R. M. Hoek; J. Minnen; P. R. Benjamin

1994-01-01

132

Prenatal Gonadal Steroids Affect Adult Spatial Behavior, CA1 and CA3 Pyramidal Cell Morphology in Rats  

Microsoft Academic Search

The present study assessed whether prenatal androgen and estrogen exposure affected adult spatial learning and hippocampal morphology. Water maze performance, the CA1 and CA3 pyramidal cell field, and the dentate gyrus-granule cell layer (DG-GCL) morphology were assessed at adulthood (70+ days of age) in males, females, androgen-treated (testosterone propionate, TP, or dihydrotestosterone propionate, DHTP) females (2–4 mg\\/day), estradiol benzoate (EB)-treated

Ceylan Isgor; Dale R. Sengelaub

1998-01-01

133

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.

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

2012-01-01

134

Morphological transformation and catalase activity of Syrian hamster embryo cells treated with hepatic peroxisome proliferators, TPA and nickel sulphate.  

PubMed

The abilities of the hepatic peroxisome proliferators (HPPs) clofibrate, di(2-ethylhexyl)phthalate (DEHP), mono(2-ethylhexyl)-phthalate (MEHP), 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4,5-trichlorophenoxy acetic acid (2,4,5-T) and tiadenol to induce morphological transformation and to increase the catalase activity of Syrian hamster embryo (SHE) cells were studied. DEHP, MEHP, clofibrate and tiadenol induced morphological transformation of SHE cells and increased the catalase activity. DEHP was more potent than clofibrate and tiadenol in both inducing catalase and morphological transformation, while MEHP seemed more potent than DEHP in inducing catalase, but not morphological transformation, 2,4,5-T and 2,4-D did not induce morphological transformation, but 2,4,5-T was more potent than clofibrate in increasing the catalase activity. These results show that several HPPs induce morphological transformation of SHE cells and an increase in the catalase activity. There is, however, no direct connection between these two parameters, as seen from the results of 2,4,5-T. The tumor promoter TPA, and the metal salt nickel sulphate, induced morphological transformation of SHE cells without any appreciable increase in the catalase activity. These results further corroborate the dissociation between induction of morphological transformation and the increase in catalase activity. PMID:2334865

Mikalsen, S O; Holen, I; Sanner, T

1990-01-01

135

Single cell growth rate and morphological dynamics revealing an "opportunistic" persistence.  

PubMed

Bacteria persistence is a well-known phenomenon, where a small fraction of cells in an isogenic population are able to survive high doses of antibiotic treatment. Since the persistence is often associated with single cell behaviour, the ability to study the dynamic response of individual cells to antibiotics is critical. In this work, we developed a gradient microfluidic system that enables long-term tracking of single cell morphology under a wide range of inhibitor concentrations. From time-lapse images, we calculated bacterial growth rates based on the variations in cell mass and in cell number. Using E. coli and Comamonas denitrificans to amoxicillin inhibition as model systems, we found the IC50 determined via both methods are in a good agreement. Importantly, the growth rates together with morphological dynamics of individual cells has led to the discovery of a new form of persistence to amoxicillin. Normal cells that are sensitive to amoxicillin gain persistence or recover from the killing process, if they have had an opportunity to utilise the cytoplasm released from lysed cells close-by. We term this acquired persistence in normal growing cells "opportunistic persistence". This finding might shed new insights into biofilm resistance and the effect of antibiotics on environmental microbes. PMID:24733150

Li, Bing; Qiu, Yong; Glidle, Andrew; Cooper, Jon; Shi, HanChang; Yin, HuaBing

2014-06-01

136

Src-mediated morphology transition of lung cancer cells in three-dimensional organotypic culture.  

PubMed

A fribotic tumor microenvironment promotes progression of cancer. In this study, we utilize a reconstituted basement membrane mimics Matrigel based three-dimensional organotypic culture (rBM 3-D) to investigate the mechanisms that mediate the tumor promoting effects of the fibrogenic mediators TGF-?1 and type I collagen (Col-1) on lung adenocarcinoma cells. Similar to normal alveolar epithelial cells, the well-differentiated lung adenocarcinoma cells in rBM 3-D culture undergo acinar morphogeneis that features polarized epithelial cell spheres with a single central lumen. Either TGF-?1 or Col-1 modestly distorts acinar morphogenesis. On the other hand, TGF-?1 and Col-1 synergistically induce a transition from acinar morphology into stellate morphology that is characteristic of invasive and metastatic cancer cells. Inhibition of the Src kinase activity abrogates induction of stellate morphology, activation of Akt and mTOR, and the expression of tumor promoting genes by TGF-?1 and Col-1. To a similar extent, pharmacological inhibition of mTOR abrogates the cellular responses to TGF-?1 and Col-1. In summary, we demonstrate that TGF-?1 and Col-1 promote stellate morphogenesis of lung cancer cells. Our findings further suggest that the Src-Akt-mTOR axis mediates stellate morphogenesis. These findings also indicate that rBM 3-D culture can serve as an ideal platform for swift and cost-effective screening of therapeutic candidates at the interface of the tumor and its microenvironment. PMID:23409704

Nguyen, Hong T; Zhuang, Yan; Sun, Lichun; Kantrow, Steven P; Kolls, Jay K; You, Zongbing; Zhuo, Ying; Shan, Bin

2013-01-01

137

Morphological and ultrastructural changes in tobacco BY-2 cells exposed to microcystin-RR.  

PubMed

Tobacco BY-2 cells were exposed to microcystin-RR (MC-RR) at two concentrations, 60 microg mL(-1) and 120 microg mL(-1), to study the changes in morphology and ultrastructure of cells as a result of the exposure. Exposure to the lower concentration for 5 d led to typical apoptotic morphological changes including condensation of nuclear chromatin, creation of a characteristic 'half moon' structure, and cytoplasm shrinkage and decreased cell volume, as revealed through light microscopy, fluorescence microscopy, and transmission electron microscopy, respectively. Exposure to the higher concentration, on the other hand, led to morphological and ultrastructural changes typical of necrosis, such as rupture of the plasma membrane and the nuclear membrane and a marked swelling of cells. The presence of many vacuoles containing unusual deposits points to the involvement of vacuoles in detoxifying MC-RR. Results of the present study indicate that exposure of tobacco BY-2 cells to MC-RR at a lower concentration (60 microg mL(-1)) results in apoptosis and that to a higher concentration (120 microg mL(-1)), in necrosis. PMID:19501874

Huang, Wenmin; Xing, Wei; Li, Dunhai; Liu, Yongding

2009-08-01

138

Morphological study of accessory gland of Bothrops jararaca and its secretory cycle.  

PubMed

The venom gland apparatus of Bothrops jararaca is composed of four distinct parts: main venom gland, primary duct, accessory gland and secondary duct. Despite the numerous studies concerning morphology and venom production and secretion in the main venom gland, there are few studies about the accessory gland and its secretion. We characterized the accessory gland of B. jararaca snake and determined the secretion cycle by morphological analysis using light and transmission electron microscopy. Our data showed that the accessory gland of B. jararaca has a simple secretory epithelium with at least six types of cells in the anterior region: two types of secretory cells, mitochondria-rich cells without secretory vesicles, horizontal cells, dark cells and basal cells, and in the posterior region a simple epithelium with two types of cells: seromucous cells and horizontal cells. Furthermore, the mucous secretory cells of the accessory gland show a delayed and massive exocytosis that occurs four days after the extraction of venom. Morphological analysis at different steps after venom extraction showed that the accessory gland has a long cycle of production and secretion, which is not synchronous with the main venom gland secretory cycle. PMID:22227156

Sakai, Fernanda; Carneiro, Sylvia M; Yamanouye, Norma

2012-03-01

139

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

140

Electrophysiology of morphologically identified mossy cells of the dentate hilus recorded in guinea pig hippocampal slices.  

PubMed

A specific population of cells located in the hilus of the hippocampal fascia dentata was studied in guinea pig hippocampal slices using standard intracellular recording techniques. Twenty-one such cells were characterized using electrophysiological techniques and were identified morphologically as mossy cells following intracellular injection of the fluorescent dye Lucifer yellow. These cells had a resting membrane potential (mean, -64.6 mV), action potential amplitude (mean, 78.6 mV), action potential duration (mean, 2.2 msec), and time constant (mean, 24.2 msec) similar to those of hippocampal pyramidal cells of area CA3. Rectification seen in their I-V curves, and their ability to fire action potentials in accommodating trains or bursts in response to injected current pulses, were also similar to those of area CA3 pyramidal cells. However, these cells could be distinguished from area CA3 pyramidal cells by their higher input resistance (mean, 97.4 M omega) and higher level of spontaneous activity. The synaptic responses of mossy cells were also different from those of CA3 pyramidal cells. First, mossy cells responded to low levels of stimulation in all areas of the hippocampal slice that were tested, even areas as remote as area CA1. Second, the responses of mossy cells to stimulation consisted primarily of EPSPs. Hyperpolarizing IPSP-like events followed EPSPs in some cells, but the hyperpolarizations were small and monophasic, even after the cell was depolarized with current injection. This response contrasts with the smaller EPSP and the prominent, biphasic IPSP elicited by afferent stimulation of area CA3 pyramidal cells. The physiological and morphological characteristics of these cells suggest that they could play an important role in the integration of electrical activity in the hippocampus. PMID:2461436

Scharfman, H E; Schwartzkroin, P A

1988-10-01

141

Embolic pneumopathy induced by oleic acid. A systematic morphologic study.  

PubMed Central

This paper presents a systematic study of acute and chronic pulmonary lesions resulting from a single intravenous injection of oleic acid and a new fibrosis lung model is proposed: pulmonary interstitial fibrosis is obtained by means of a number of oleic acid intravenous injections. Nineteen adult dogs received 0.045 g/kg or 0.09 g/kg of oleic acid. A systematic morphologic study was carried out after 1, 2, 3, 4, 6, 12, 24, and 48 hours and 1, 2 and 4 weeks. Eleven other adult dogs received weekly one injection of 0.09 g/kg of pure oleic acid over a period of 1 to 3 months. Examination of the lung was carried out by means of light and electron microscopy and morphometry. An early stage characterized by the formation of thrombosis and cellular necrosis was followed by a repair stage with the proliferation of Type 2 cells and fibrotic foci in the subpleural areas. Lipid staining with Sudan IV allowed the onset and disappearance of lipid-laden macrophages to be ascertained. The late stage showed pulmonary fibrosis. The extent of the lesions is related to the number of oleic acid injections. Since interstitial pulmonary fibrosis invariably appeared, and only 2 dogs out of 11 died, the model is satisfactory for pathologist and physiologist. Images Figure 4 Figure 5 Figure 12 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 1 Figure 2 Figure 3

Derks, C. M.; Jacobovitz-Derks, D.

1977-01-01

142

Three-dimensional morphology of the pericellular matrix of intervertebral disc cells in the rat  

PubMed Central

Intervertebral disc cells are surrounded by a pericellular matrix that is biochemically and morphologically distinct from other extracellular matrix regions. Although the function of the pericellular matrix is not fully understood, prior studies of pericellular matrix-chondrocyte regions in articular cartilage (termed ‘chondrons’) suggest that the size, shape, and mechanical properties of the pericellular matrix significantly influence the micromechanical environment of the contained cells. A first step in understanding the role of the pericellular matrix in the intervertebral disc is to quantify the three-dimensional morphology and zonal variations of these regions across the disc. In this study, three-dimensional reconstructions and morphometric measurements of pericellular matrix-cell regions were obtained in situ using fluorescence confocal microscopy of en bloc sections of nucleus pulposus and anulus fibrosus of the rat disc immunolabeled for type VI collagen. The morphology of the pericellular matrix and cells varied significantly across regions, with distinct pericellular matrix aspect ratios (largest/smallest diameter) showing shapes that were generally large and rounded in the nucleus pulposus (average of 1.9), and ellipsoidal and discoidal in the inner (2.4) and outer anulus fibrosus (2.8). The average pericellular matrix volume per cell was found to be significantly larger in the nucleus (6424 µm3) than that of inner (1903 µm3) and outer (1433 µm3) anulus. Pericellular matrix regions containing 1 or 2 cells were the dominant subgroup in the rat intervertebral disc at both 1 and 12 months of age. Multicellular pericellular matrix regions were present more often in the younger nucleus pulposus and outer anulus fibrosus. The orientation of the pericellular matrix regions further varied significantly across the disc, reflecting local collagen matrix architecture. These studies provide new information on the organization and shape of intervertebral disc cells and their surrounding pericellular matrix, which may provide new insights into the mechanisms that regulate cell-matrix interactions.

Cao, Li; Guilak, Farshid; Setton, Lori A

2007-01-01

143

Morphological and electron transport studies in ZnO dye-sensitized solar cells incorporating multi- and single-walled carbon nanotubes  

NASA Astrophysics Data System (ADS)

Dye-sensitized solar cells (DSSCs) incorporating zinc oxide (ZnO) nanostructures and carbon nanotubes (CNTs) were fabricated using a chemical bath deposition method. The nanoflake structures captured by a field-emission scanning electron microscopy analysis traced the appearance of multi-walled carbon nanotubes (MWCNTs) and single-walled carbon nanotubes (SWCNTs) in the photoanode thin film. The photovoltaic performance of the photoanode was quantified by means of an electrochemical impedance spectroscopy (EIS) unit with GAMRY-Physical Electrochemistry. The ZnO-SWCNT-based DSSC exhibited good photovoltaic performance with power conversion efficiency (?), photocurrent density (Jsc), open-circuit voltage (Voc) and fill factor (FF) of 1.31%, 15.31 mA cm-2, 0.224 V and 0.36, respectively. The EIS unit was also employed to quantify the charge transport resistance (Rct), transport resistance (Rt) and effective electron lifetime (?eff) of the DSSC. The impedance analysis of the ZnO-SWCNT-based DSSC also determined greater highly efficient electron transport due to long effective electron diffusion length than the film thickness of the photoanode.

Omar, Azimah; Abdullah, Huda; Ambar Yarmo, Mohd; Shaari, Sahbudin; Raihan Taha, Mohd

2013-04-01

144

Morphological and Phytochemical Studies on 'Asparagus filifolius' BERTOL. (Liliaceae).  

National Technical Information Service (NTIS)

The study is based on the species Asparagus filifolius collected from khzana, a small islet close to the west bank of Euphrates river near Haditha (Iraq). The morphological study was carried out on both male and female plants collected at different stages...

A. H. Al-Khayat, A. Kery, N. K. Al-Khazaraji

1989-01-01

145

Acquisition of L2 English Morphology: A Family Case Study  

ERIC Educational Resources Information Center

This study investigates the status of morphology in the L2 English of three members of a family from Indonesia (parents and their 5-year-old daughter) who have lived, studied or worked in Australia for a year. The investigation is contextualized against various learning settings in which the informants have learned English: formal instruction in…

Zhang, Yanyin; Widyastuti, Ima

2010-01-01

146

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.

Parameswaran, Neetha; Matsui, Ken; Gupta, Neetu

2011-01-01

147

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

148

Photovoltaic properties dependance on the active layer morphology of small molecule organic solar cells  

Microsoft Academic Search

The active layer morphology of vacuum deposited organic solar cells based on phthalocyanine-perylene donor-acceptor couple have been studied, comparing coevaporated bulk heterojunction with multilayer structures consisting in alternated donor and acceptor very thin layers. These latter devices show current-voltage behaviour indicating that their active layer acts as an interpenetrated network. They show better photovoltaic parameters, with power conversion efficiencies 2.5

Roshanak Radbeh; Bernard Ratier; Wassim Hojeij; Benoit Brousse; André Moliton

2006-01-01

149

Spray-dried porcine plasma affects intestinal morphology and immune cell subsets of weaned pigs  

Microsoft Academic Search

The aim of this study was to evaluate the effects of dietary spray-dried porcine plasma (SDPP) on the productive performance, intestinal morphology and leukocyte cell subsets of piglets. Sixteen early-weaned piglets (20±2 d) were distributed into two dietary treatments: 1) free access to control diet or 2) 6% SDPP in the control diet instead of soy-protein concentrate. Intestinal morphometry of the

M. Nofrarías; E. G. Manzanilla; J. Pujols; X. Gibert; N. Majó; J. Segalés; J. Gasa

2007-01-01

150

Influence of Thrombin Concentration on the Mechanical and Morphological Properties of Cell-seeded Fibrin Hydrogels  

PubMed Central

Fibrin is a biopolymer that has been used in a variety of biomaterial, cell delivery and tissue engineering applications. The enzyme thrombin catalyzes the formation of fibrin microfibrils, which form a three-dimensional mesh in which cells can be directly embedded at the time of gel formation. In this study, fibrin hydrogels containing vascular smooth muscle cells were created using varying concentrations of thrombin. Over 7 days in culture, all gels decreased in volume as the fibrin matrix compacted, and the degree of gel compaction increased as thrombin concentration decreased. The material modulus and ultimate tensile stress of the gels also increased with decreasing thrombin concentration. Addition of thrombin to similar constructs made using collagen Type I did not show an effect on gel compaction or mechanical properties, suggesting that these effects were a result of thrombin’s action on fibrin polymerization, and not cellular functions. Cell proliferation in fibrin hydrogels was not significantly affected by thrombin addition. Matrix examination using scanning electron microscopy showed increasing fibrin fiber diameters as thrombin concentration decreased. Confocal microscopic imaging of the actin cytoskeleton showed that cell morphology on two-dimensional substrates of fibrin showed marked changes, with higher thrombin concentrations producing cells with longer cellular projections. However, these morphological changes were not as apparent in cells embedded in three-dimensional (3-D) matrices, in which cells exhibited a similar morphology independent of thrombin concentration. These results relate features of the matrix and cellular components of 3-D fibrin constructs to mechanical properties, and contribute to the understanding of structure-function relationships in cell-seeded, 3-D protein hydrogels.

Rowe, Shaneen L.; Lee, SungYun; Stegemann, Jan P.

2007-01-01

151

Morphology and infectivity of virus that persistently caused infection in an AGS cell line.  

PubMed

A recent report has indicated that proteins and genes of simian virus 5 (SV5) are detected in a human gastric adenocarcinoma (AGS) cell line, which is widely provided for oncology, immunology, and microbiology research. However, the production of infective virions has not been determined in this cell line. In this study, the morphology and infectivity of the virus particles of the AGS cell line were studied by light and electron microscopy and virus transmission assay. The virus particles were approximately 176.0 ± 41.1 nm in diameter. The particles possessed projections 8-12 nm long on the surface and contained a nucleocapsid determined to be 13-18 nm in width and less than 1,000 nm in length. The virus was transmissible to the Vero cell line, induced multinuclear giant cell formation, and reproduced the same shape of antigenic virions. In this study, the persistently infected virus in the AGS cell line was determined to be infective and form reproducible virions, and a new morphological feature of SV5 was determined. PMID:22179184

Ooi, Yukimasa; Daikoku, Eriko; Wu, Hong; Aoki, Hiroaki; Morita, Chizuko; Nakano, Takashi; Kohno, Takehiro; Takasaki, Tomohiko; Sano, Kouichi

2011-12-01

152

Morphological and ultrastructural features of Iba1-immunolabeled microglial cells in the hippocampal dentate gyrus  

PubMed Central

Microglia are found throughout the central nervous system, respond rapidly to pathology and are involved in several components of the neuroinflammatory response. Iba1 is a marker for microglial cells and previous immunocytochemical studies have utilized this and other microglial-specific antibodies to demonstrate the morphological features of microglial cells at the light microscopic level. However, there is a paucity of studies that have used microglial-specific antibodies to describe the ultrastructural features of microglial cells and their processes. The goal of the present study is to use Iba1 immuno-electron microscopy to elucidate the fine structural features of microglial cells and their processes in the hilar region of the dentate gyrus of adult Sprague-Dawley rats. Iba1-labeled cell bodies were observed adjacent to neurons and capillaries, as well as dispersed in the neuropil. The nuclei of these cells had dense heterochromatin next to the nuclear envelope and lighter chromatin in their center. Iba1-immunolabeling was found within the thin shell of perikaryal cytoplasm that contained the usual organelles, including mitochondria, cisternae of endoplasmic reticulum and Golgi complex. Iba1-labeled cell bodies also commonly displayed an inclusion body. Iba1-labeled cell bodies gave rise to processes that often had a small side branch arise within 5 ?m of the microglial cell body. These data showing “resting” Iba-1 labeled microglial cells in the normal adult rat dentate gyrus provide a basis for comparison with the morphology of microglial cells in disease and injury models where they are activated or phagocytotic.

Shapiro, Lee A.; Perez, Zachary D.; Foresti, Maira L.; Arisi, Gabriel M.; Ribak, Charles E.

2009-01-01

153

Unraveling the nanoscale morphologies of mesoporous perovskite solar cells and their correlation to device performance.  

PubMed

Hybrid solar cells based on organometal halide perovskite absorbers have recently emerged as promising class for cost- and energy-efficient photovoltaics. So far, unraveling the morphology of the different materials within the nanostructured absorber layer has not been accomplished. Here, we present the first visualization of the mesoporous absorber layer in a perovskite solar cell from analytical transmission electron microscopy studies. Material contrast is achieved by electron spectroscopic imaging. We found that infiltration of the hole transport material into the scaffold is low and inhomogeneous. Furthermore, our data suggest that the device performance is strongly affected by the morphology of the TiO2 scaffold with a fine grained structure being disadvantageous. PMID:24702643

Nanova, Diana; Kast, Anne Katrin; Pfannmöller, Martin; Müller, Christian; Veith, Lisa; Wacker, Irene; Agari, Michaela; Hermes, Wilfried; Erk, Peter; Kowalsky, Wolfgang; Schröder, Rasmus R; Lovrin?i?, Robert

2014-05-14

154

Morphological changes in the sulfur electrode of lifecycle-tested Na/S cells  

SciTech Connect

Morphological studies of the sulfur electrode have provided important insights into the factors that influence the performance of Na/S cells. The observed compositional gradients indicate that multiple reaction fronts arise within the electrode during cycling through the two-liquid compositional range. Present models predicting this behavior inadequately describe the location of these fronts. The pattern of changes in Na and S distribution is repeated with each charge-discharge cycle; however, the morphology is progressively altered by corrosion products, especially the migratory compounds of NaAlS/sub 2/ and NaCrS/sub 2/. As a result of a cycle-dependent transport mechanism, the latter compound becomes concentrated in the electrode adjacent to the electrolyte. Cells that fail because of electrolyte fractures form solid sodium polysulfides within the sulfur electrode. On occasion, the uncontrolled growth of solid phases undermines the integrity of the container.

Smaga, J.A.

1986-01-01

155

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

156

Blends of Liquid Crystalline Polyesters and Polyethylene Terephthalate - Morphological Studies  

Microsoft Academic Search

Polyethylene terephthalate (PET) was blended with two different kinds of liquid crystalline (LC) polyesters with the level of LC polyester varying from 5 to 15 weight %. Homogeneous samples were prepared by melt blending the polymers in twin screw extruder. The crystallization and morphology of these blends was studied with the help of differential scanning calorimetry (DSC), small angle light

S. K. Sharma; A. Tendolkar; A. Misra

1988-01-01

157

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.

2014-01-01

158

Morphological and physiological evidence for interstitial cell of Cajal-like cells in the guinea pig gallbladder  

PubMed Central

Gallbladder smooth muscle (GBSM) exhibits spontaneous rhythmic electrical activity, but the origin and propagation of this activity are not understood. We used morphological and physiological approaches to determine whether interstitial cells of Cajal (ICC) are present in the guinea pig extrahepatic biliary tree. Light microscopic studies involving Kit tyrosine kinase immunohistochemistry and laser confocal imaging of Ca2+ transients revealed ICC-like cells in the gallbladder. One type of ICC-like cell had elongated cell bodies with one or two primary processes and was observed mainly along GBSM bundles and nerve fibres. The other type comprised multipolar cells that were located at the origin and intersection of muscle bundles. Electron microscopy revealed ICC-like cells that were rich in mitochondria, caveolae and smooth endoplasmic reticulum and formed close appositions between themselves and with GBSM cells. Rhythmic Ca2+ flashes, which represent Ca2+ influx during action potentials, were synchronized in any given GBSM bundle and associated ICC-like cells. Gap junction uncouplers (1-octanol, carbenoxolone, 18?-glycyrrhetinic acid and connexin mimetic peptide) eliminated or greatly reduced Ca2+ flashes in GBSM, but they persisted in ICC-like cells, whereas the Kit tyrosine kinase inhibitor, imanitib mesylate, eliminated or reduced action potentials and Ca2+ flashes in both cell types, as well as associated tissue contractions. This study provides morphological and physiological evidence for the existence of ICC-like cells in the gallbladder and presents data supporting electrical coupling between ICC-like and GBSM cells. The results support a role for ICC-like cells in the generation and propagation of spontaneous rhythmicity, and hence, the excitability of gallbladder.

Lavoie, Brigitte; Balemba, Onesmo B; Nelson, Mark T; Ward, Sean M; Mawe, Gary M

2007-01-01

159

Morphological and functional restoration of parietal cells in Helicobacter pylori associated enlarged fold gastritis after eradication  

PubMed Central

BACKGROUND/AIM—Helicobacter pylori infections are associated with hypochlorhydria in patients with pangastritis. It has previously been shown that eradication of H pylori leads to an increase in acid secretion in H pylori associated enlarged fold gastritis, suggesting that H pylori infection affects parietal cell function in the gastric body. The aim of this study was to evaluate the effects of H pylori infection on parietal cell morphology and function in hypochlorhydric patients.?PATIENTS/METHODS—The presence of H pylori infection, mucosal length, and inflammatory infiltration were investigated in six patients with enlarged fold gastritis and 12 patients without enlarged folds. Parietal cell morphology was examined by immunohistochemistry using an antibody against the ? subunit of H+,K+-ATPase and electron microscopy. In addition, gastric acid secretion and fasting serum gastrin concentration were determined before and after the eradication of H pylori.?RESULTS—In the H pylori positive patients with enlarged fold gastritis, fold width, foveolar length, and inflammatory infiltration were increased. In addition, the immunostaining pattern of H+, K+-ATPase was less uniform, and the percentage of altered parietal cells showing dilated canaliculi with vacuole-like structures and few short microvilli was greatly increased compared with that in H pylori positive patients without enlarged folds. After eradication, fold width, foveolar length, and inflammatory infiltrates decreased and nearly all parietal cells were restored to normal morphology. On the other hand, altered parietal cells were negligible in H pylori negative patients. In addition, the basal acid output and tetragastrin stimulated maximal acid output increased significantly from 0.5 (0.5) to 4.1 (1.5) mmol/h and from 2.5 (1.2) to 13.8 (0.7) mmol/h (p<0.01), and fasting serum gastrin concentrations decreased significantly from 213.5 (31.6) to 70.2 (7.5) pg/ml (p<0.01) after eradication in patients with enlarged fold gastritis.?CONCLUSION—The morphological changes in parietal cells associated with H pylori infection may be functionally associated with the inhibition of acid secretion seen in patients with enlarged fold gastritis.???Keywords: Helicobacter pylori; enlarged fold gastritis; parietal cell morphology; acid secretion; gastrin

Murayama, Y; Miyagawa, J; Shinomura, Y; Kanayama, S; Yasunaga, Y; Nishibayashi, H; Yamamori, K; Higashimoto, Y; Matsuzawa, Y

1999-01-01

160

Primary non-secretory plasma cell leukemia with atypical morphology — a case report  

Microsoft Academic Search

Only one case of primary non-secretory plasma cell leukemia with atypical morphology has been reported thus far. Here we report\\u000a another such case of plasma cell leukemia diagnosed on fl ow cytometry, as morphological heterogeneity and lack of monoclonal\\u000a immunoglobulins in both serum and urine, made it difficult to come to a conclusive diagnosis based purely on morphology.

T. Dadu; A. Rangan; A. Handoo; M. Bhargava

2009-01-01

161

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

162

Morphological characterization of periodontium-derived human stem cells.  

PubMed

The aim of this study has been to characterize adult human somatic periodontium-derived stem cells (PDSCS) isolated from human periodontium and to follow their differentiation after cell culture. PDSCS were isolated from human periodontal tissue and cultured as spheres in serum-free medium. After 10 days the primary spheres were dissociated and the secondary spheres sub-cultured for another 1-2 weeks. Cells from different time points were analyzed, and immunohistochemical and electron microscopic investigations carried out. Histological analysis showed differentiation of spheres deriving from the PDSCS with central production of extracellular matrix beginning 3 days after sub-culturing. Isolated PDSCS developed pseudopodia which contained actin. Tubulin was found in the central portion of the cells. Pseudopodia between different cells anastomosed, indicating intercellular transport. Immunostaining for osteopontin demonstrated a positive reaction in primary spheres and within extracellular matrix vesicles after sub-culturing. In cell culture under serum-free conditions human PDSCS form spheres which are capable of producing extracellular matrix. Further investigations have do be carried out to investigate the capability of these cells to differentiate into osteogenic progenitor cells. PMID:20591640

Arnold, Wolfgang H; Becher, Sebastian; Dannan, A; Widera, Darius; Dittmar, T; Jacob, Monica; Mannherz, Hans Georg; Dittmar, Thomas; Kaltschmidt, B; Kaltschmidt, C; Grimm, Wolf-Dieter

2010-08-20

163

Mitohormesis in muscle cells: a morphological, molecular, and proteomic approach.  

PubMed

Low-level oxidative stress induces an adaptive response commonly defined as hormesis; this type of stress is often related to reactive oxygen species (ROS) originating from the mitochondrial respiratory chain (mitochondrial hormesis or mitohormesis). The accumulation of transient low doses of ROS either through chronic physical activity or caloric restriction influences signaling from the mitochondrial compartment to the cell, reduces glucose metabolism, induces mitochondrial metabolism, increases stress resistance and ultimately, increases lifespan. Mitochondrial formation of presumably harmful levels (chronic and/or excessive) of ROS within skeletal muscle has been observed in insulin resistance of obese subjects, type 2 diabetes mellitus, as well as in impaired muscle function associated with normal aging. Advances in mitochondrial bioimaging combined with mitochondrial biochemistry and proteome research have broadened our knowledge of specific cellular signaling and other related functions of the mitochondrial behavior. In this review, we describe mitochondrial remodeling in response to different degrees of oxidative insults induced in vitro in myocytes and in vivo in skeletal muscle, focusing on the potential application of a combined morphological and biochemical approach. The use of such technologies could yield benefits for our overall understanding of physiology for biotechnological research related to drug design, physical activity prescription and significant lifestyle changes. PMID:24596688

Barbieri, Elena; Sestili, Piero; Vallorani, Luciana; Guescini, Michele; Calcabrini, Cinzia; Gioacchini, Anna Maria; Annibalini, Giosuè; Lucertini, Francesco; Piccoli, Giovanni; Stocchi, Vilberto

2013-10-01

164

Mitohormesis in muscle cells: a morphological, molecular, and proteomic approach  

PubMed Central

Summary Low-level oxidative stress induces an adaptive response commonly defined as hormesis; this type of stress is often related to reactive oxygen species (ROS) originating from the mitochondrial respiratory chain (mitochondrial hormesis or mitohormesis). The accumulation of transient low doses of ROS either through chronic physical activity or caloric restriction influences signaling from the mitochondrial compartment to the cell, reduces glucose metabolism, induces mitochondrial metabolism, increases stress resistance and ultimately, increases lifespan. Mitochondrial formation of presumably harmful levels (chronic and/or excessive) of ROS within skeletal muscle has been observed in insulin resistance of obese subjects, type 2 diabetes mellitus, as well as in impaired muscle function associated with normal aging. Advances in mitochondrial bioimaging combined with mitochondrial biochemistry and proteome research have broadened our knowledge of specific cellular signaling and other related functions of the mitochondrial behavior. In this review, we describe mitochondrial remodeling in response to different degrees of oxidative insults induced in vitro in myocytes and in vivo in skeletal muscle, focusing on the potential application of a combined morphological and biochemical approach. The use of such technologies could yield benefits for our overall understanding of physiology for biotechnological research related to drug design, physical activity prescription and significant lifestyle changes.

Barbieri, Elena; Sestili, Piero; Vallorani, Luciana; Guescini, Michele; Calcabrini, Cinzia; Gioacchini, Anna Maria; Annibalini, Giosue; Lucertini, Francesco; Piccoli, Giovanni; Stocchi, Vilberto

2013-01-01

165

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.

Garcia-Pinto, Angelica B.; Santos-Filho, Sebastiao D.; Carvalho, Jorge J.; Pereira, Mario J. S.; Fonseca, Adenilson S.; Bernardo-Filho, Mario

2013-01-01

166

Discontinuities in Rap1 activity determine epithelial cell morphology within the developing wing of Drosophila  

PubMed Central

Mechanisms that govern cell-fate specification within developing epithelia have been intensely investigated, with many of the critical intercellular signaling pathways identified, and well characterized. Much less is known, however, about downstream events that drive the morphological differentiation of these cells, once their fate has been determined. In the Drosophila wing-blade epithelium, two cell types predominate: vein and intervein. After cell proliferation is complete and adhesive cell-cell contacts have been refined, the vast majority of intervein cells adopt a hexagonal morphology. Within vein territories, however, cell-shape refinement results in trapezoids. Signaling events that differentiate between vein and intervein cell fates are well understood, but the genetic pathways underlying vein/intervein cyto-architectural differences remain largely undescribed. We show here that the Rap1 GTPase plays a critical role in determining cell-type-specific morphologies within the developing wing epithelium. Rap1, together with its effector Canoe, promotes symmetric distribution of the adhesion molecule DE-cadherin about the apicolateral circumference of epithelial cells. We provide evidence that in presumptive vein tissue Rap1/Canoe activity is down-regulated, resulting in adhesive asymmetries and non-hexagonal cell morphologies. In particular Canoe levels are reduced in vein cells as they morphologically differentiate. We also demonstrate that over-expression of Rap1 disrupts vein formation both in the developing epithelium and the adult wing blade. Therefore, vein/intervein morphological differences result, at least in part, from the patterned regulation of Rap1 activity.

O'Keefe, David D.; Gonzalez-Nino, Eduardo; Edgar, Bruce A.; Curtiss, Jennifer

2012-01-01

167

Morphological changes of ricin toxin-induced apoptosis in human cervical cancer cells.  

PubMed

The morphological changes of ricin-induced apoptosis in a human cervical cancer cell line were studied. To shed light on the mechanism of action of ricin toxin (RT) at the cellular level, we examined cell growth, apoptosis, changes of mitochondrial membrane potential (MMP) and cytochrome C translocation in HeLa cells by exposing these cells to RT for indicated times. The effect of RT on cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS), inner salt; MTS assay and apoptosis were measured using flow cytometry, fluorescence microscopy and electron microscopy. Changes in MMP were monitored using flow cytometry. Western blot analysis was used to evaluate the release of mitochondrial cytochrome C. RT noticeably inhibited the proliferation of HeLa cells, and the half maximal inhibitory concentration dose was about 100 ng/ml. HeLa cells treated with RT showed typical characteristics of apoptosis rather than necrosis, including phosphatidylserine exposed from the inner to the outer leaflet of the plasma membrane, abnormal cell morphology, chromatin condensation and nuclear fragmentation. In contrast, during the process of cellular apoptosis, the messenger RNA (mRNA) and protein expression of cytochrome C in treated and untreated Hela cells were not significantly changed (data not shown). However, when cells were treated with RT, the massive translocation of cytochrome C to the nucleus was evident. Our results indicate that RT-induced HeLa cell apoptosis, especially for cytochrome C translocation, may play an important role in apoptosis induced by RT. PMID:21937530

Liao, Peng; Liu, Wensen; Li, Hongyang; Gao, Hongwei; Wang, Haiying; Li, Nan; Xu, Na; Li, Jiping; Wan, Jiayu; Liu, Linna; Sun, Yucheng

2012-06-01

168

Morphological transformation induced by glass fibers in BALB/c-3T3 cells.  

PubMed

Studies were conducted to determine whether 1) glass fibers can induce morphological transformation in BALB/c-3T3 cells, 2) the transforming activity of glass fibers is related to fiber size, and 3) transformed cells induced by glass fibers possess neoplastic properties. In the transformation assay, BALB/c-3T3 cells were treated with three different types of glass fibers: Manville code 100 (JM-100, Manville Corp., Denver, CO), Owens-Corning AAA-10 (AAA-10, Owens-Corning Corp., Toledo, OH), and Owens-Corning general building insulation (ISL, Owens-Corning Corp.) fibers. The neoplastic properties were investigated using the soft agar cloning and gene transfection methods. All three different glass fibers were cytotoxic at high concentrations and induced dose-related increases in morphological transformation. The transforming activity was inversely related to fiber size, with AAA-10 showing higher activity than JM-100 and JM-100 showing higher activity than ISL fiber. Transformed cells induced by glass fibers exerted anchorage-independent growth (90%) and DNA transfection-mediated transformation (100%). These results indicate that glass fibers are capable of transforming mammalian (BALB/c-3T3) cells in vitro as a function of their physical properties and that glass fiber-induced transformed cells possess preneoplastic characteristics. PMID:8525469

Gao, H G; Whong, W Z; Jones, W G; Wallace, W E; Ong, T

1995-01-01

169

[Comparison of bone marrow and blood cell morphology between refractory anemia and other anemia disease].  

PubMed

This study was purposed to investigate the cell morphological features of bone marrow and peripheral blood in patients with myelodysplastic syndrome, mainly with refractory anemia, and to compare them with other anemia diseases including chronic aplastic anemia, hemolytic anemia and megaloblastic anemia. The bone marrow and peripheral blood were taken from patients for preparing the smears with Wright staining. 500 karyocytes in bone marrow and 100 karyocytes in peripheral blood were detected, and the features of morbid cells of erythrocyte, granulocyte and megakaryocytic series were observed. The results showed that differences between refractory anemia, chronic aplastic anemias and hemolytic anemia as well as megaloblastic anemia were statistically significant (P < 0.05) in the granules scarce and absence in the intracytoplasm of segmented neutrocyte in peripheral blood, Pelger dyskaryosis, the numbers and detected rate of immature granulocytes, monocyte detected rate, the granules scarce in all stage of granulocytic series in bone marrow, odd number and prolification of nucleolus in erythrocytic series, little macronucleus and single circle nucleus macronucleus. It is concluded that cell morphology is the foundation of diagnosing the MDS, the abnormality morphology both in peripheral blood and bone marrow play the consequence role in the diagnosis of MDS. PMID:23257446

Cheng, Hong; Jiang, Ming; DU, Wei; Zhong, Di; Hao, Jian-Ping; Li, Ling

2012-12-01

170

Coccoid forms of Helicobacter pylori are the morphologic manifestation of cell death.  

PubMed Central

Helicobacter pylori can transform from its normal helical bacillary morphology to a coccoid morphology. Since this coccoid form cannot be cultured in vitro, it has been speculated that it is a dormant form potentially involved in the transmission of H. pylori and in a patient's relapse after antibiotic therapy. In this study we determined the effects of aging, temperature, aerobiosis, starvation, and antibiotics on the morphologic conversion rate and culturability of H. pylori. Aerobiosis and the addition of a bactericidal antibiotic to the culture medium resulted in the highest conversion rate. During the conversion to coccoid forms, the cultures always lost culturability at the stage where 50% of the organisms were still in bacillary form; this result indicated that culturability and coccoid morphology are two separate but related entities. Independent of the conditions used to induce the conversion into coccoids, the morphological conversion was accompanied by several marked antigenic and ultrastructural changes. Also, both the total amounts and the integrity of RNA and DNA were significantly reduced in coccoid forms. With the potential-sensitive probe diOC(5)-3, a clear loss of membrane potential in coccoid forms was observed. Inhibition of protein or RNA synthesis by the addition of bacteriostatic antibiotics did not prevent the conversion to coccoid forms but resulted in an increased conversion rate. Hence, we conclude that conversion of H. pylori from the bacillary to the coccoid form is a passive process that does not require protein synthesis. Our data suggest that the coccoid form of H. pylori is the morphologic manifestation of bacterial cell death.

Kusters, J G; Gerrits, M M; Van Strijp, J A; Vandenbroucke-Grauls, C M

1997-01-01

171

DSC Study of Morphological Changes in Segmented Polyurethane Elastomers  

Microsoft Academic Search

Annealing studies were carried out to investigate the morphological changes in segmented polyurethane elastomers (PUR) induced by annealing as a function of temperature. Four series of PUR elastomers were studied by varying the hard segment type (MDI\\/BD and H12MDI\\/BD), the content of the hard segment (35-57% by weight), the soft segment type (PTMO and PCL) and the soft segment molecular

E. Govorcin Bajsic; V. Rek; A. Sendijarevic; V. Sendijarevic; K. C. Frisch

2000-01-01

172

Morphological and metastatic murine melanoma variants: motility, adhesiveness, cell surface and in vivo properties.  

PubMed Central

The behaviour in vivo of tight and loose variants of murine melanoma cells is further characterized. In vitro clonal morphology is reproduced on a variety of substrates. Results suggest that repeated selection of loose cells can co-select for cells with high metastatic and colonization potentials. Measurement of cell motility shows that 1G3 (loose) cells are more motile than 1G8 (tight) which are restricted to movements within clonal boundaries. Studies of adhesive properties show that loose cells are more easily detached from the substrate with trypsin or EDTA and that both cell lines attach more quickly to monolayers of loose cells than to tight ones. No gross differences are found either in attachment rates to plastic and ECM or in aggregation and disaggregation rates. Analysis of the cell surface has not revealed any differences between 1G8 and 1G3 in the sialylation of terminal galactose and N-acetylgalactosamine residues or in neuraminidase releasable sialic acid. The binding patterns of iodinated lectins to SDS-PAGE separated proteins are similar for both lines except for one 85/90 KD protein which is more abundant in 1G3 than 1G8 cells after neuraminidase treatment. The results show enhanced differences in metastatic potential of tight and loose clones after selective cloning and that there may be important differences in motility and cell-substrate interactions. Images Figure 1 Figure 6

Clark, S. R.; Brody, J. S.; Sidebottom, E.

1987-01-01

173

Cartography of cell morphology in tomato pericarp at the fruit scale.  

PubMed

In fleshy fruits, the variability of cell morphology at the fruit scale is largely unknown. It presents both a huge variability and a high level of organization. Better knowledge of cell morphology heterogeneity within the fruit is necessary to understand fruit development, to model fruit mechanical behaviour, or to investigate variations of physico-chemical measurements. A generic approach is proposed to build cartographies of cell morphology at the fruit scale, which depict regions corresponding to different cell morphologies. The approach is based on: (1) sampling the whole fruit at known positions; (2) imaging and quantifying local cell morphology; (3) pooling measurements to take biological variability into account and (4) projecting results in a morphology model of the whole fruit. The result is a synthetic representation of cell morphology variations within the whole fruit. The method was applied to the characterization of cell morphology in tomato pericarp. Two different imaging scales that provided complementary descriptions were used: 3D confocal microscopy and macroscopy. The approach is generic and can be adapted to other fruits or other products. PMID:22612643

Legland, D; Devaux, M-F; Bouchet, B; Guillon, F; Lahaye, M

2012-07-01

174

Morphologically homogeneous red blood cells present a heterogeneous response to hormonal stimulation.  

PubMed

Red blood cells (RBCs) are among the most intensively studied cells in natural history, elucidating numerous principles and ground-breaking knowledge in cell biology. Morphologically, RBCs are largely homogeneous, and most of the functional studies have been performed on large populations of cells, masking putative cellular variations. We studied human and mouse RBCs by live-cell video imaging, which allowed single cells to be followed over time. In particular we analysed functional responses to hormonal stimulation with lysophosphatidic acid (LPA), a signalling molecule occurring in blood plasma, with the Ca(2+) sensor Fluo-4. Additionally, we developed an approach for analysing the Ca(2+) responses of RBCs that allowed the quantitative characterization of single-cell signals. In RBCs, the LPA-induced Ca(2+) influx showed substantial diversity in both kinetics and amplitude. Also the age-classification was determined for each particular RBC and consecutively analysed. While reticulocytes lack a Ca(2+) response to LPA stimulation, old RBCs approaching clearance generated robust LPA-induced signals, which still displayed broad heterogeneity. Observing phospatidylserine exposure as an effector mechanism of intracellular Ca(2+) revealed an even increased heterogeneity of RBC responses. The functional diversity of RBCs needs to be taken into account in future studies, which will increasingly require single-cell analysis approaches. The identified heterogeneity in RBC responses is important for the basic understanding of RBC signalling and their contribution to numerous diseases, especially with respect to Ca(2+) influx and the associated pro-thrombotic activity. PMID:23840765

Wang, Jue; Wagner-Britz, Lisa; Bogdanova, Anna; Ruppenthal, Sandra; Wiesen, Kathrina; Kaiser, Elisabeth; Tian, Qinghai; Krause, Elmar; Bernhardt, Ingolf; Lipp, Peter; Philipp, Stephan E; Kaestner, Lars

2013-01-01

175

R-Ras induces malignant, but not morphologic, transformation of NIH3T3 cells.  

PubMed

Although previous studies have not identified transforming properties of the Ras-related protein R-Ras, two recent observations have prompted our further evaluation of R-Ras function. First, we observed that mutant forms of the closely related R-Ras2/TC21 protein (approximately 70% identity) exhibited the same potent transforming activity as oncogenic Ras proteins. Second, R-Ras association with Bcl-2 suggested a possible role for R-Ras in apoptotic growth control. Therefore, we have performed a detailed analysis of R-Ras transforming potential in NIH3T3 cells. Whereas expression of a mutant R-Ras protein (38V; analogous to the 12V activating Ras mutation) did not induce morphologic transformation of NIH3T3 cells, R-Ras(38V)-expressing cells proliferated in low serum, formed colonies in soft agar, and formed progressive tumors in nude mice. Like Ras-transformed cells, R-Ras(38V)-transformed cells exhibited constitutively activated mitogen activated protein kinases. Furthermore, R-Ras(38V) stimulated transcriptional activation of Ras-responsive promoter elements, and this activity (and transformation) was blocked by Raf dominant negative proteins. Finally, whereas co-expression of Bcl-2 did not cause significant alteration in wild type or mutant R-Ras transforming activity, coexpression of v-Myc and R-Ras(38V) induced a striking morphologic transformation of NIH3T3 cells. Taken together, these observations suggest that aberrant R-Ras function may stimulate malignant transformation, in the absence of morphologic transformation, via up-regulation of part of the Ras signal transduction pathway. PMID:7936652

Cox, A D; Brtva, T R; Lowe, D G; Der, C J

1994-11-01

176

Differentiation of human alveolar epithelial cells in primary culture: morphological characterization and synthesis of caveolin-1 and surfactant protein-C  

Microsoft Academic Search

Human alveolar type II cells were isolated from lung tissue and cultured for several days. The morphology of cells was investigated at different time points postseeding and the synthesis of alveolar cell-type specific proteins was analyzed using different methods. The rationale of the study was to characterize a primary cell culture of human alveolar cells for the development of an

Sabine Fuchs; Andrew John Hollins; Michael Laue; Ulrich Friedrich Schaefer; Klaus Roemer; Mark Gumbleton; Claus-Michael Lehr

2003-01-01

177

Effects of the radiocontrast agent iodixanol on endothelial cell morphology and function.  

PubMed

Iodinated radiocontrast media (RCM) are usually well tolerated, but their large and increasing use renders their toxicity a relevant problem, especially in high risk patients. The aim of the study was to investigate the possible toxic or activating effects of iodixanol on endothelial cells (EC) and the putative in vitro protective action of N-acetylcysteine and rosuvastatin. Morphology, oxidative status, redistribution of heat-shock protein 60 and secretion of proinflammatory products were studied in cultured human EC through confocal microscopy, immunofluorescence and immuno-enzymatic methods. EC reacted to iodixanol with shrinking and bulging, increase in intracellular oxidation and translocation of Heat Shock Protein 60 to the cell membrane. The secretion of proinflammatory products was strongly stimulated by sequential incubation of EC with iodixanol and TNF? (p<0.00001 for all tested molecules, namely TNF?, IL-8, sVCAM-1, MCP-1, and IL-6). N-acetylcysteine prevented morphologic and oxidative derangements, and significantly reduced proinflammatory product secretion (P range<0.0001 to<0.00001 for TNF?, VCAM-1, MCP-1, and IL-6); rosuvastatin inhibited morphology and oxidative modifications only. Our data help clarifying the mechanisms of early and late toxicity of RCM and support the use of anti-oxidant and anti-inflammatory agents for optimization of radiological procedures in high risk patients. PMID:22985912

Ronda, Nicoletta; Potì, Francesco; Palmisano, Alessandra; Gatti, Rita; Orlandini, Guido; Maggiore, Umberto; Cabassi, Aderville; Regolisti, Giuseppe; Fiaccadori, Enrico

2013-01-01

178

Morphology and function of cells of human embryonic liver in monolayer culture.  

PubMed

A system for culturing human fetal liver cells in monolayers is described and the effects of various conditions of growth on the morphology and function of the cultured cells are presented. The addition of 10% calf serum or 1% human serum to the growth medium accelerated the proliferation of the liver cells, with subsequent loss of characteristic morphology and specific functional activity. In the absence of serum, the cultured liver cells retained their morphology and their function for at least 4 wk, as evidenced by secretion of serum albumin and storage of glycogen and iron. PMID:4104969

Bissell, D M; Tilles, J G

1971-07-01

179

MORPHOLOGY AND FUNCTION OF CELLS OF HUMAN EMBRYONIC LIVER IN MONOLAYER CULTURE  

PubMed Central

A system for culturing human fetal liver cells in monolayers is described and the effects of various conditions of growth on the morphology and function of the cultured cells are presented. The addition of 10% calf serum or 1% human serum to the growth medium accelerated the proliferation of the liver cells, with subsequent loss of characteristic morphology and specific functional activity. In the absence of serum, the cultured liver cells retained their morphology and their function for at least 4 wk, as evidenced by secretion of serum albumin and storage of glycogen and iron.

Bissell, D. Montgomery; Tilles, Jeremiah G.

1971-01-01

180

Morphological and molecular analysis of angiogenesis after intramyocardial transplantation of autologous bone marrow mononuclear cells.  

PubMed

We studied the peculiarities of angiogenesis in the postinfarction period after transmyocardial laser revascularization and intramyocardial implantation of mononuclear bone marrow cells into the pericicatrical zone of the left ventricular myocardium in dogs. Morphological manifestation of angiogenesis in the myocardium after application of laser and cell technologies are angiomatosis, formation of large thin-wall vessels and sinusoids. The angiogenic effect of implanted mononuclear bone marrow cells is determined by high content (43-47%) of CD31+ cells in both adherent and nonadherent fractions. More pronounced angiogenic potential of nonadherent cells is determined by intensive expression of cytokine VEGF-B and D mRNA essential for arterial vessels growth. Immunohistochemical studies showed that about 90% cells of the nonadherent fraction are endothelial precursors expressing endothelial cell markers isolectin B4 and VEGF-R2. It was found that the use of adherent mononuclear bone marrow cells during the postinfarction period induces ossification of the epicardium and subepicardial myocardium layer, formation of cartilage plates, and focal calcification. Implantation of nonadherent mononuclear bone marrow cells into transmyocardial laser channels did not induce ectopic ossification of the myocardium. PMID:21234455

Sergeevichev, D S; Larionov, P M; Subbotin, D V; Lushnikova, E L; Novruzov, R B; Karas'kov, A M; Nepomnyashchikh, L M

2010-10-01

181

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.

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

2012-01-01

182

Real-time sensing of cell morphology by infrared waveguide spectroscopy.  

PubMed

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

Yashunsky, Victor; Marciano, Tal; Lirtsman, Vladislav; Golosovsky, Michael; Davidov, Dan; Aroeti, Benjamin

2012-01-01

183

Morphological and electrical studies of organic semiconductor thin films  

NASA Astrophysics Data System (ADS)

The morphology of an organic semiconductor (OSC) material used as the active layer in an organic device has dramatic effect in the final performance of the device. However, understanding the growth dynamics that governs OSC thin-film morphology is far from complete. The growth theories have been applied to the inorganic semiconductor thin films successfully to reveal their growth dynamics. It would therefore be natural to extend such analyses to OSC thin-film growth. After all, understanding the mechanisms behind the growth of these materials will ultimately afford one with the ability to control their morphology favorably. However, there have so far been few systematic works on OSC materials. A significant portion of my dissertation work here deals with the study of the growth morphology of small-molecule OSCs such as pentacene and perylene, as two model OSCs due to their auspicious charge-carrier mobilities, on various substrates using scanning probe microscopy (SPM). For the former, Monte Carlo computer simulations and kinetic roughening theory were employed to reveal the growth mechanisms behind its peculiar morphology. For the latter, island size distribution and the kinetic roughening analyses were performed. Especially, deliberate emphasis has been placed on the growth of pentacene on SiO 2, due to pentacene's relatively high charge-carrier mobility and SiO 2's technological relevance. Such a study has not been done before. My analysis of the growth of pentacene on SiO2 shows that the initial monolayer growth exhibits a novel growth morphology that involves not only fractal growth but also mound growth. The terraces of the growing mounds have a fractal dimension of 1.6, indicating a lateral DLA shape. The power spectrum analysis shows a ring structure in momentum space, which corresponds to a length selection in real space, indicating the existence of mounds. What starts out to be diffusion-driven growth, ends up, with more coverage, incorporating also the Schwoebel barrier effect. The latter disrupts the highly desired layer-by-layer quasi-epitaxial growth and forms instead the now often-encountered, but not fully understood, pyramidal pentacene mounds. The critical exponents, the roughness exponent alpha = 0.57 +/- 0.03, the growth exponent beta = 0.27 +/- 0.03 of the real surface compare well with the simulation results, alpha = 0.48 +/- 0.07, beta = 0.29 +/- 0.01. Such a morphology wedding fractal growth with mound growth was not observed before in any other system. In addition to the morphological studies, my thesis also includes the results from the electrical measurements I have done on some of the OSC molecular solids using conducting-probe atomic force microscopy (CP-AFM), and the fabrication and study of feasibility of organic static induction transistor (OSIT) with promising OSCs such as pentacene, perylene, tris(quinoline-8-hydroxylate)aluminum (Alq), and N,N'-di(4-methylphenyl)-N,N' -diphenylbenzidine (TPD). The former two failed to produce viable SITs due to their poor film quality, while the latter two gave rise to functioning SITs. Morphology has thus been shown to have crucial effect in the operation of static induction transistors. The charge transport through SIT was Ohmic at low voltages, and space-charge-limited at higher voltages.

Zorba, Serkan

184

Redox regulation of morphology, cell stiffness, and lectin-induced aggregation of human platelets.  

PubMed

Redox regulation and carbohydrate recognition are potent molecular mechanisms which can contribute to platelet aggregation in response to various stimuli. The purpose of this study is to investigate the relationship between these mechanisms and to examine whether cell surface glycocalyx and cell stiffness of human platelets are sensitive to the redox potential formed by glutathione. To this end, human platelets were treated with different concentrations (0.05 ?M to 6 mM) and ratios of reduced or oxidized glutathione (GSH or GSSG), and platelet morphological, mechanical, and functional properties were determined using conventional light microscopy, atomic force microscopy, and lectin-induced cell aggregation analysis. It was found that lowering the glutathione redox potential changed platelet morphology and increased platelet stiffness as well as modulated nonuniformly platelet aggregation in response to plant lectins with different carbohydrate-binding specificity including wheat germ agglutinin, Sambucus nigra agglutinin, and Canavalia ensiformis agglutinin. Extracellular redox potential and redox buffering capacity of the GSSG/2GSH couple were shown to control the availability of specific lectin-binding glycoligands on the cell surface, while the intracellular glutathione redox state affected the general functional ability of platelets to be aggregated independently of the type of lectins. Our data provide the first experimental evidence that glutathione as a redox molecule can affect the mechanical stiffness of human platelets and induce changes of the cell surface glycocalyx, which may represent a new mechanism of redox regulation of intercellular contacts. PMID:21079947

Shamova, Ekaterina V; Gorudko, Irina V; Drozd, Elizaveta S; Chizhik, Sergey A; Martinovich, Grigory G; Cherenkevich, Sergey N; Timoshenko, Alexander V

2011-02-01

185

Dynamics of Nontypical Apoptotic Morphological Changes Visualized by Green Fluorescent Protein in Living Cells with Infectious Pancreatic Necrosis Virus Infection  

PubMed Central

Morphologically, apoptotic cells are characterized by highly condensed membrane blebbing and formation of apoptotic bodies. Recently, we reported that apoptosis precedes necrosis in a fish cell line infected with infectious pancreatic necrosis virus (IPNV). In the present study, we tested the possibility that nontypical apoptosis is a component of IPNV-induced fish cell death. A variant type of green fluorescent protein (EGFP) was expressed in a fish cell line such that EGFP served as a protein marker for visualizing dynamic apoptotic cell morphological changes and for tracing membrane integrity changes during IPNV infection. Direct morphological changes were visualized by fluorescence microscopy by EGFP in living cells infected with IPNV. The nontypical apoptotic morphological change stage occurred during the pre-late stage (6 to 7 h postinfection). Nontypical apoptotic features, including highly condensed membrane blebbing, occurred during the middle apoptotic stage. At the pre-late apoptotic stage, membrane vesicles quickly formed, blebbed, and were finally pinched off from the cell membrane. At the same time, at this pre-late apoptotic stage, apoptotic cells formed unique small holes in their membranes that ranged from 0.39 to 0.78 ?m according to examination by scanning electron microscopy and immunoelectron microscopy. Quantitation of the intra- and extracellular release of EGFP by CHSE-214-EGFP cells after IPNV infection was done by Western blotting and fluorometry. Membrane integrity was quickly lost during the late apoptotic stage (after 8 h postinfection), and morphological change and membrane integrity loss could be prevented and blocked by treatment with apoptosis inhibitors such as cycloheximide, genistein, and EDTA before IPNV infection. Together, these findings show the apoptotic features at the onset of pathology in host cells (early and middle apoptotic stages), followed secondarily by nontypical apoptosis (pre-late apoptotic stage) and then by postapoptotic necrosis (late apoptotic stage), of a fish cell line. Our results demonstrate that nontypical apoptosis is a component of IPNV-induced fish cell death.

Hong, Jiann-Ruey; Lin, Tai-Lang; Yang, Jer-Yen; Hsu, Ya-Li; Wu, Jen-Leih

1999-01-01

186

Morphological studies of uncompatibilized and compatibilized polystyrene\\/polypropylene blend  

Microsoft Academic Search

Morphological studies of uncompatibilized and compatibilized polystyrene\\/polypropylene (PS\\/PP) blends with 20\\/80, 50\\/50 and 80\\/20 (wt%), were carried out through melt blending in a single screw extruder at a blend temperature of 200°C and a screw speed of 40rpm. Various compatibilizers, viz. polystyrene-block-poly(ethylene-butylene)-block polystyrene (SEBS), Surlyn®, ethylene vinyl acetate (EVA) and sodium salt hydrate of 4 styrenesulfonic acid (4ssa,ssh) with concentration

A Halimatudahliana; H Ismail; M Nasir

2002-01-01

187

A screen for morphological complexity identifies regulators of switch-like transitions between discrete cell shapes.  

PubMed

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 haemocytes in culture are a heterogeneous mixture of five discrete morphologies. In an RNAi screen of genes affecting the morphological complexity of heterogeneous cell 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 R; Perrimon, Norbert; Marshall, Christopher J; Wong, Stephen T C; Bakal, Chris

2013-07-01

188

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.

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

2014-01-01

189

Cellular and Cytoskeleton Morphology and Strength of Adhesion of Cells on Self-Assembled Monolayers of Organosilanes  

Microsoft Academic Search

The objective of this study was to explore the potential use of self-assembled monolayers (SAMs) of alkylamine and arylalkyamine as well-defined, homogeneous, tailoredin vitromodel surfaces for exploring the effect of hydrodynamic flow on morphology and strength of adhesion of human umbilical vein endothelial cells. The cell surface area, shape, f-actin distribution, and adhesion strength of human umbilical vein endothelial cells

Ravi Kapur; Alan S. Rudolph

1998-01-01

190

The pterygopalatine ganglion in humans: a morphological study.  

PubMed

As a rule the pterygopalatine ganglion (PPG) is considered to be a single structure of the parasympathetic nervous system, associated with the maxillary nerve in the pterygopalatine fossa (PPF). A few structural studies in humans are available in the indexed references. We designed the present study of the PPG in order to provide evidence of possible variations in morphological patterns of the PPG. We performed dissections of the PPF on 20 human adult heads, using different approaches. The dissected specimens were stained with hematoxylin-eosin and silver (Bielschowsky) or prepared for immunohistochemistry for synaptophisin and neurofilament. Four morphological types of the PPG were defined macroscopically: A (10%): partitioned PPG, the upper partition receiving the vidian nerve; B (55%): single, the upper part (base) receiving the vidian nerve; C (15%): single, but the vidian nerve reaches the lower part (tip) of the ganglion; D (20%): partitioned, the lower partition receiving the vidian nerve. We propose that it may be inappropriate to invariably regard the PPG as a single morphological structure. From individual to individual the PPG may present either as a single ganglion or as a partitioned one, with distinct superior and inferior components. Nevertheless, the presence of the dispersed pterygopalatine microganglia (DPPG) evidenced by histochemistry and immunohistochemistry serves to complete an individually variable morphological pattern of a structure usually described as single. The individual variation may be the reason for failures in ablation procedures of the PPG; partitions of the PPG and/or the DPPG may functionally correlate with specific territories and targets and further tracing studies may be helpful in validating or invalidating this theory. PMID:19124232

Rusu, M C; Pop, F; Curc?, G C; Podoleanu, L; Voinea, L M

2009-04-01

191

Cell morphology of extrusion foamed poly(lactic acid) using endothermic chemical foaming agent.  

PubMed

Poly(lactic acid) (PLA) was foamed with an endothermic chemical foaming agent (CFA) through an extrusion process. The effects of polymer melt flow index, CFA content, and processing speed on the cellular structures, void fraction, and cell-population density of foamed PLA were investigated. The apparent melt viscosity of PLA was measured to understand the effect of melt index on the cell morphology of foamed PLA samples. The void fraction was strongly dependent on the PLA melt index. It increased with increasing melt index, reaching a maximum value, after which it decreased. Melt index showed no significant effect on the cell-population density of foamed samples within the narrow range studied. A gas containment limit was observed in PLA foamed with CFA. Both the void fraction and cell-population density increased with an initial increase in CFA content, reached a maximum value, and then decreased as CFA content continued to increase. The processing speed also affected the morphology of PLA foams. The void fraction reached a maximum value as the extruder's screw speed increased to 40 rpm and a further increase in the processing speed tended to reduce the void fraction of foamed samples. By contrast, cell-population density increased one order of magnitude by increasing the screw speed from 20 to 120 rpm. The experimental results indicate that a homogeneous and finer cellular morphology could be successfully achieved in PLA foamed in an extrusion process with a proper combination of polymer melt flow index, CFA content, and processing speed. PMID:19615893

Matuana, Laurent M; Faruk, Omar; Diaz, Carlos A

2009-12-01

192

Rho GTPases in PC3 prostate cancer cell morphology, invasion and tumor cell diapedesis  

Microsoft Academic Search

Background The Rho GTPases comprise one of the eight subfamilies of the Ras superfamily of monomeric GTP-binding proteins and are involved\\u000a in cytoskeletal organization. Previously, using a dominant negative construct, we demonstrated a role for RhoC GTPase in conferring\\u000a invasive capabilities to PC-3 human prostate cancer cells. Further, we demonstrated that inactivation of RhoC led to morphological\\u000a changes commensurate with

Linda Sequeira; Cara W. Dubyk; Tracy A. Riesenberger; Carlton R. Cooper; Kenneth L. van Golen

2008-01-01

193

IN VITRO NEOPLASTIC TRANSFORMATION OF MOUSE SKIN CELLS: MORPHOLOGY AND ULTRASTRUCTURE OF CELLS AND TUMORS  

Microsoft Academic Search

Mixed cultures of epidermal and dermal cells from term fetuses of Balb\\/cAn mice were exposed to high concentrations (50 ?g\\/ml) of 7. 12-dimethylbenz(a)anthracene (DMBA) in medium containing Tween-80 or to medium with Tween-80 alone for 45 min. Within 5 weeks the cultures exposed to DMBA began to exhibit accelerated growth in vitro and an epithelioid morphology. These same changes occurred

Peter M. Elias; Stuart H. Yuspa; Marisa Gullino; David L. Morgan; Richard R. Bates; Marvin A. Lutzner

1974-01-01

194

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...

195

Unveiling shapes: Shapelets for galaxy morphology and gravitational lensing studies  

NASA Astrophysics Data System (ADS)

The shapelet basis system forms a convenient and mathematically well-established framework for describing shapes of galaxies and the telescope's point spread function (PSF). A shapelet-based image processing pipeline thus offers remarkable benefits: For weak-lensing studies, its analytic and efficient deconvolution procedure from arbitrary PSFs constitutes a significant improvement on the traditional KSB method. For complex morphologies of the lensed galaxy ensemble, it has proven to belong to the most accurate shear measurement methods available today. Furthermore, a multitude of shear estimators can be formed from the expansion coefficients, which allows cross-checking of measurements. For statistical investigation of galaxy morphologies, one profits from the significant dimensionality reduction and scale-invariance provided by the shapelet decomposition. Unfortunately, overfitting the data and unphysical high-frequency oscillations pose apparent limitations to its applicability. These problems can be remedied by minor modifications to the decomposition and deconvolution procedures.

Melchior, Peter

2008-12-01

196

Nanopattern-induced changes in morphology and motility of smooth muscle cells  

PubMed Central

Cells are known to be surrounded by nanoscale topography in their natural extracellular environment. The cell behavior, including morphology, proliferation, and motility of bovine pulmonary artery smooth muscle cells (SMC) were studied on poly(methyl methacrylate) (PMMA) and poly(dimethylsiloxane) (PDMS) surfaces comprising nanopatterned gratings with 350 nm linewidth, 700 nm pitch, and 350 nm depth. More than 90% of the cells aligned to the gratings, and were significantly elongated compared to the SMC cultured on non-patterned surfaces. The nuclei were also elongated and aligned. Proliferation of the cells was significantly reduced on the nanopatterned surfaces. The polarization of microtubule organizing centers (MTOC), which are associated with cell migration, of SMC cultured on nanopatterned surfaces showed a preference towards the axis of cell alignment in an in vitro wound healing assay. In contrast, the MTOC of SMC on non-patterned surfaces preferentially polarized towards the wound edge. It is proposed that this nanoimprinting technology will provide a valuable platform for studies in cell-substrate interactions and for development of medical devices with nanoscale features.

Yim, Evelyn K.F.; Reano, Ron M.; Pang, Stella W.; Yee, Albert F.; Chen, Christopher S.; Leong, Kam W.

2008-01-01

197

Nonperturbative Imaging of Nucleoid Morphology in Live Bacterial Cells during an Antimicrobial Peptide Attack.  

PubMed

Studies of time-dependent drug and environmental effects on single, live bacterial cells would benefit significantly from a permeable, nonperturbative, long-lived fluorescent stain specific to the nucleoids (chromosomal DNA). The ideal stain would not affect cell growth rate or nucleoid morphology and dynamics, even during laser illumination for hundreds of camera frames. In this study, time-dependent, single-cell fluorescence imaging with laser excitation and a sensitive electron-multiplying charge-coupled-device (EMCCD) camera critically tested the utility of "dead-cell stains" (SYTOX orange and SYTOX green) and "live-cell stains" (DRAQ5 and SYTO 61) and also 4',6-diamidino-2-phenylindole (DAPI). Surprisingly, the dead-cell stains were nearly ideal for imaging live Escherichia coli, while the live-cell stains and DAPI caused nucleoid expansion and, in some cases, cell permeabilization and the halting of growth. SYTOX orange performed well for both the Gram-negative E. coli and the Gram-positive Bacillus subtilis. In an initial application, we used two-color fluorescence imaging to show that the antimicrobial peptide cecropin A destroyed nucleoid-ribosome segregation over 20 min after permeabilization of the E. coli cytoplasmic membrane, reminiscent of the long-term effects of the drug rifampin. In contrast, the human cathelicidin LL-37, while similar to cecropin A in structure, length, charge, and the ability to permeabilize bacterial membranes, had no observable effect on nucleoid-ribosome segregation. Possible underlying causes are suggested. PMID:24907320

Bakshi, Somenath; Choi, Heejun; Rangarajan, Nambirajan; Barns, Kenneth J; Bratton, Benjamin P; Weisshaar, James C

2014-08-15

198

Phase contrast microscopy of living cells within the whole lens: spatial correlations and morphological dynamics  

PubMed Central

Purpose Images from cultured lens cells do not convey enough spatial information, and imaging of fixed lens specimens cannot reveal dynamic changes in the cells. As such, a real-time, convenient approach for monitoring label-free imaging of dynamic processes of living cells within the whole lens is urgently needed. Methods Female Wistar rat lenses were kept in organ culture. Insulin-like growth factor-I was added to the culture medium to induce cell mitosis. A novel method of ultraviolet (UV) irradiation was used to induce cell apoptosis and fiber damage. The cellular morphological dynamics within the whole lens were monitored by inverted phase contrast microscopy. Apoptosis was assessed using a commercial kit with Hoechst 33342/YO-PRO®-1/propidium iodide (PI). Results The intrinsic transparency and low-light scattering property of the rat lens permitted direct imaging of the lens epithelial cells (LECs) and the superficial fiber cells. We visualized the processes of mitosis and apoptosis of the LECs, and we obtained dynamic images of posterior fiber cells following UVA irradiation. Conclusions This method opens a new window for observing lens cells in their physiologic location, and it can be readily applied in studies on lens physiology and pathology.

Kong, Zhiying; Zhu, Xiangjia; Zhang, Shenghai; Wu, Jihong

2012-01-01

199

Morphology Favors an Endothelial Cell Pathway for Longitudinal Conduction within Arterioles  

Microsoft Academic Search

We examined the morphological parameters of arteriolar endothelial and smooth muscle cell dimensions and gap junctional surface areas to obtain an indication of the coupling capacity of each cell type. Silver nitrate staining was utilized to define cell borders of endothelial and smooth muscle cells in arterioles of several vascular beds from two species. From video images of silver-stained arterioles,

Tara L. Haas; Brian R. Duling

1997-01-01

200

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

201

The effect of morphology upon mobility: Implications for bulk heterojunction solar cells with nonuniform blend morphology  

NASA Astrophysics Data System (ADS)

We use a Monte Carlo model to predict the effect of composition, domain size, and energetic disorder upon the mobility of carriers in an organic donor-acceptor blend. These simulations show that, for the changes in local morphology expected within the thickness of a typical bulk heterojunction photovoltaic device, changes in mobility of more than an order of magnitude are expected. The impact of nonuniform mobility upon space-charge-limited diode and photovoltaic (PV) device performance is examined using a drift-diffusion model. The current passing through a space-charge-limited diode is shown to depend upon the position of the layers with differing mobility. Accurate modeling of the current in such devices can only be achieved using a drift-diffusion model incorporating nonuniform mobility. Inserting a 20 nm thick layer in which the mobility is less by one order of magnitude than in the rest of the 70 nm thick PV device reduced the device efficiency by more than 20%. Therefore it seems vital to exert a high degree of control over the morphology throughout the entire blend PV device, otherwise potential PV performance may be lost.

Groves, C.; Koster, L. J. A.; Greenham, N. C.

2009-05-01

202

Matching neural morphology to molecular expression: single cell injection following immunostaining.  

PubMed

To match a neuron's morphology with its expression of a particular protein, it is useful to first identify the cell by immunostaining and then inject it with fluorescent dye. Such targeted injection cannot be performed with a hydrophilic dye (such as Lucifer yellow) because the neuron, once rendered porous to antibodies, does not retain it. But a lipophilic dye (such as DiI) injected iontophoretically into the soma forms a crystal and is thereby trapped. From this intracellular depot dye diffuses into the cell membrane to reveal the detailed morphology. We have used this strategy to identify the morphology of a GABAergic retinal bipolar cell and several types of GABAergic amacrine cell. In addition, we demonstrate probable connections from a narrow-field, GABAergic amacrine cell to the OFF brisk-transient ganglion cell. Finally, we show that the strategy works in the cortical slice, showing a layer IV cell immunostained for parvalbumin to be a "nest basket cell". PMID:14724387

Kao, Yen-Hong; Sterling, Peter

2003-03-01

203

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.

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

204

Tyrosine phosphorylation and morphological transformation induced by four vanadium compounds on MC3T3E1 cells.  

PubMed

The present study was performed to determine the phosphotyrosine-protein levels induced by insulin and by four vanadium derivatives in MC3T3E1 osteoblast-like cells. We have also attempted to associate these patterns with the vanadium-induced growth and morphological changes of such cells. Vanadate (Vi), vanadyl (VO), bis(maltolato)oxovanadium (IV) (BMOV) and bis(maltolato)dioxovanadium (V) (BMV) stimulate cell growth in a narrow range of concentration, but are also inhibitors for the cells at high concentrations. Vanadium-treated cells displayed clear changes in their morphology after overnight incubation. However, BMV was the least cytotoxic and the weakest inducer of morphological changes. All the compounds promote the phosphorylation of tyrosine residues in several proteins. This effect was more pronounced at low than at high doses. At low doses (10 microM), BMV showed a phosphorylation pattern similar to that of insulin, while Vi, VO and BMOV induced strong phosphorylation of cell proteins. The present findings suggest that the vanadium-induced growth regulation and morphological changes in MC3T3E1 osteoblast-like cells are associated with the ability of these agents to increase the phosphotyrosine protein levels and to inhibit phosphotyrosine phosphatases. These properties are dependent on the oxidation state as well as on the organic ligand which coordinates the vanadium atom. PMID:10497886

Sálice, V C; Cortizo, A M; Gómez Dumm, C L; Etcheverry, S B

1999-08-01

205

Effects of cucurbitacins on cell morphology are associated with sensitization of renal carcinoma cells to TRAIL-induced apoptosis  

PubMed Central

Cucurbitacins B and D were among the compounds identified as sensitizers of cancer cells to TRAIL-mediated apoptosis in a high-throughput screen. Therefore a series of cucurbitacins was further investigated for TRAIL sensitization and possible mechanisms of action. A total of six cucurbitacins promoted TRAIL-induced apoptosis (B, I, E, C, D, and K) and one (P) was inactive. Sensitization of renal adenocarcinoma cells to TRAIL was apparent after as little as 1–4 h pretreatment and did not require continued presence of cucurbitacin. Active cucurbitacins induced caspase-8 activation only after subsequent TRAIL addition and caspase activation was required for apoptosis suggesting amplified proximal signaling from TRAIL death receptors. Cucurbitacin-sensitized TRAIL-induced cytotoxicity was inhibited by N-acetyl cysteine. Structure–activity relationship analysis in comparison to published studies suggests that TRAIL-sensitizing and general cytotoxic activities of cucurbitacins may be decoupled. Cucurbitacins are reported to be inhibitors of STAT3 activation. However, their TRAIL-sensitizing activity is STAT3-independent. Treatment of renal carcinoma cells with active cucurbitacins produced rapid and dramatic changes in cell morphology and cytoskeletal organization (also prevented by NAC). Therefore, cucurbitacins may be useful as tools for investigating the molecular mechanism(s) of action of TRAIL sensitizers, particularly with regard to temporal aspects of sensitization and modulation of TRAIL signaling by cell morphology, and could form the basis for future therapeutic development in combination with TRAIL death receptor agonists.

Thomas, Cheryl L.; Brooks, Alan D.; Booth, Nancy Lynn; Lowery, Evan M.; Pompei, Richard J.; McMahon, James B.; Sayers, Thomas J.

2012-01-01

206

Cell morphology and PSP?toxin profiles of Alexandrium minutum in the Marlborough Sounds, New Zealand  

Microsoft Academic Search

Thecal plate morphology and paralytic shellfish poisoning (PSP) toxin spectra produced by three strains of a small Alexandrium species isolated from the Marlborough Sounds, New Zealand were examined. Although these cells displayed minor morphological features described in the literature as characteristic of both A. minutum and A. lusitanicum, the former designation was adopted. High performance liquid chromatography (HPLC) analysis of

Lincoln MacKenzie; Natasha Berkett

1997-01-01

207

Functional and morphologic characteristics of the leukemic cells of a patient with acute monocytic leukemia: correlation with clinical features.  

PubMed

The clinical course of a patient with acute monocytic leukemia and prominent infiltration of the skin and testes is described. In vitro studies demonstrated that the circulating monocyte precursors were capable of adherence to nylon fibers, and phagocytosis of bacteria and latex particles. In vivo, migration of leukemic cells to skin windows was observed. Extreme nuclear folding, marked surface activity, and morphologic features suggesting nuclear and cytoplasmic maturation were seen by light and electron microscopy. The presence of morphologically and functionally more differentiated monocytic cells may account for the marked tiuuse invasion in this patient and, possibly, in other patients with monocytic leukemia. PMID:1055611

Schiffer, C A; Sanel, F T; Stechmiller, B K; Wiernik, P H

1975-07-01

208

Morphological Analysis, Phonological Analysis and Learning To Read French: A Longitudinal Study.  

ERIC Educational Resources Information Center

Presents a longitudinal study that examines the relationship between morphological analysis, phonological analysis, and learning to read French. Finds very strong links between morphological and phonological analyses and between morphological analysis and reading. Contributes to the evidence of a link between both phonological and morphological

Casalis, Severine; Louis-Alexandre, Marie-France

2000-01-01

209

An impedance-based flow microcytometer for single cell morphology discrimination.  

PubMed

Cell shape is a fundamental biological feature, providing specific information about physiological or pathological cellular conditions. Most of the state-of-the-art microfluidic cytometers, however, only allow simple cell analysis, including viability studies, cell counting and sorting. In this work, we present a non-invasive, label-free device capable of single cell morphology discrimination in continuous flow. The device is based on the principle of liquid electrodes, fabricated in a cross configuration around a sensing zone. This arrangement allows measurement of cell impedance along orthogonal orientations and extraction of an index describing cell shape anisotropy. By adding prior to the sensing volume a series of lateral liquid electrodes, the particle stream was focused toward the channel midline and each cell was oriented in a specific direction before shape sensing. We demonstrate the proof of concept by performing spherical and elongated particle discrimination. As an application, we show that the shape changes experienced during cell division can be monitored and characterized. In particular, budding yeasts at different stages of the mitotic cycle were identified by extracting their anisotropy index. PMID:24874178

Shaker, M; Colella, L; Caselli, F; Bisegna, P; Renaud, P

2014-06-17

210

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, Begoña

2013-04-01

211

[Morphological manifestations of neonatal bronchopulmonary dysplasia and cell renewal in the lung in this condition].  

PubMed

The lungs of 184 dead neonates and babies who were from birth on artificial ventilation with rough parameters and hyperoxygenation were found to have peculiar pathohistological changes that were used to work out an illustrated algorithm for the morphological diagnosis of neonatal bronchopulmonary dysplasia (NBPD). An immunohistochemical study was used to identify the cell renewal markers Ki67, Bcl2, P53, and CPP32. In NBPD, there was an extremely high expression of all the markers in the cells of the bronchial, alveolar epithelium and lung interstitium as compared with the control group. It is concluded that cell renewal is accelerated in the lung in NBPD and the disease progresses until death occurs in infants. PMID:20369582

Samokhin, P A; Tsetkova, Iu V

2010-01-01

212

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.

2013-01-01

213

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

PubMed Central

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

1988-01-01

214

Changes in morphology, cell wall composition and soluble proteome in Rhodobacter sphaeroides cells exposed to chromate.  

PubMed

The response of the carotenoidless Rhodobacter sphaeroides mutant R26 to chromate stress under photosynthetic conditions is investigated by biochemical and spectroscopic measurements, proteomic analysis and cell imaging. Cell cultures were found able to reduce chromate within 3-4 days. Chromate induces marked changes in the cellular dimension and morphology, as revealed by atomic force microscopy, along with compositional changes in the cell wall revealed by infrared spectroscopy. These effects are accompanied by significant changes in the level of several proteins: 15 proteins were found up-regulated and 15 down-regulated. The protein content found in chromate exposed cells is in good agreement with the biochemical, spectroscopic and microscopic results. Moreover at the present stage no specific chromate-reductase could be found in the soluble proteome, indicating that detoxification of the pollutant proceeds via aspecific reductants. PMID:22661079

Italiano, Francesca; Rinalducci, Sara; Agostiano, Angela; Zolla, Lello; De Leo, Francesca; Ceci, Luigi R; Trotta, Massimo

2012-10-01

215

Spatial analysis of 3' phosphoinositide signaling in living fibroblasts, III: influence of cell morphology and morphological Polarity.  

PubMed

Activation of phosphoinositide (PI) 3-kinase is a required signaling pathway in fibroblast migration directed by platelet-derived growth factor. The pattern of 3' PI lipids in the plasma membrane, integrating local PI 3-kinase activity as well as 3' PI diffusion and turnover, influences the spatiotemporal regulation of the cytoskeleton. In fibroblasts stimulated uniformly with platelet-derived growth factor, visualized using total internal reflection fluorescence microscopy, we consistently observed localized regions with significantly higher or lower 3' PI levels than adjacent regions (hot and cold spots, respectively). A typical cell contained multiple hot spots, coinciding with apparent leading edge structures, and at most one cold spot at the rear. Using a framework for finite-element modeling with actual cell contact area geometries, we find that although the 3' PI pattern is affected by irregular contact area shape, cell morphology alone cannot explain the presence of hot or cold spots. Our results and analysis instead suggest that these regions reflect different local 3' PI dynamics, specifically through a combination of mechanisms: enhanced PI 3-kinase activity, reduced 3' PI turnover, and possibly slow/constrained 3' PI diffusion. The morphological polarity of the cell may thus bias 3' PI signaling to promote persistent migration in fibroblasts. PMID:15923219

Schneider, Ian C; Parrish, Elizabeth M; Haugh, Jason M

2005-08-01

216

Middle Eastern intestinal lymphoma: a morphological and immunohistochemical study.  

PubMed Central

A total of 31 cases of Middle Eastern gastrointestinal lymphoma (from Mosul, Iraq) has been analysed by conventional histology, and also by immunoperoxidase staining of trypsinised paraffin sections with anti-Ig and anti-J chain antisera. Histologically these neoplasms fell into three categories: undifferentiated lymphoma of Burkitt type (8 cases); follicle centre cell (FCC) lymphoma, resembling European lymphomas of FCC origin (15 cases); and Mediterranean lymphoma (MTL) (3 cases). Immunohistological staining of the FCC neoplasms showed that these tumours resembled their European counterpart in that cytoplasmic Ig and J chain could be demonstrated in a proportion of cases. However there was a striking difference in that alpha chain alone, light chain alone, or J chain alone were detected in several cases (in contrast to the predominance of mu plus kappa or lambda light chains found in European cases). Furthermore, prominent intracellular inclusions of alpha chains were found in two cases. Staining of the MTL cases revealed that the characteristic mucosal plasma cell infiltrate was positive for alpha chain (weakly) and J chain (strongly) but that the invasive cells which morphologically resembled FCCs were negative for both constituents. It is argued that these three histological categories constitute the major types of gastrointestinal lymphoma in the Middle East; and that in MTL the invasive lymphoma is of FCC type. Images

Isaacson, P; Al-Dewachi, H S; Mason, D Y

1983-01-01

217

Single-cell PCR on protargol-impregnated euplotid ciliates: a combined approach of morphological and molecular taxonomy  

Microsoft Academic Search

Ciliates are considered one of the most diverse protozoa and play significant roles in ecology. For successful taxonomic study of these microscopic eukaryotes, a staining procedure is necessary, due mainly to intrinsic difficulties in recognizing characteristics from living cells. Although molecular taxonomy has been used to resolve the ambiguities associated with traditional morphology-based taxonomy, extraction of genomic DNA from stained

Se-Joo Kim; Joong Ki Choi; Seongho Ryu; Gi-Sik Min

2011-01-01

218

Distribution and morphology of ghrelin-immunopositive cells in the cerebellum of the African ostrich.  

PubMed

Ghrelin, the endogenous ligand for the growth hormone secretagogue receptor, has been found in the cerebellum of many vertebrates and in the gastrointestinal tract of African ostrich chicks, but little is known about its distribution in the cerebellum of the African ostrich. In the present study, the distribution and morphological characteristics of ghrelin-producing cells in the cerebellum of the African ostrich were investigated using immunohistochemistry. The results indicate that the cerebellum is divided into two sections: the outer cerebellar cortex and the inner medulla of cerebellum. The cerebellar cortex comprises a molecular layer, a Purkinje cell layer and a granular layer; ghrelin-immunopositive (ghrelin-ip) cells were localized throughout the entire cerebellum, but sparsely in the medulla. The greatest number of ghrelin-ip cells was found in the stratum granulosum, and the density decreased gradually from the molecular layer to the Purkinje cell layer in the cerebellar cortex. The ghrelin-ip cells were fusiform or irregular polygons and their cytoplasm was stained intensely. These results clearly demonstrate the presence of ghrelin-ip cells in the cerebellum of the African ostrich. It is speculated that ghrelin may have a physiological function in the cerebellum. PMID:22795873

Wang, Jia-xiang; Li, Peng; Zhou, Yue

2012-12-01

219

Effect of asiatic and ursolic acids on morphology, hydrophobicity, and adhesion of UPECs to uroepithelial cells.  

PubMed

Adhesion of bacteria to epithelial tissue is an essential step in the progression of the urinary tract infections. Reduction of virulence factors responsible for microbial attachment may help to decrease or inhibit colonization of the host organism by pathogens. In the age of increasing bacterial antibiotic resistance, more and more attention is being paid to the use of plants and/or their bioactive components in the prevention and treatment of human infections. Asiatic acid (AA) and ursolic acid (UA), two plant secondary metabolites, were used as potential antibacterial agents. The current study aimed to determine the possible impact of AA and UA on morphology, hydrophobicity, and adhesion of clinical uropathogenic Escherichia coli strains (UPEC) to the uroepithelial cells. Our work describes for the first time the effects exerted by AA and UA on virulence factors of UPECs. The impact of both acids on the cell surface hydrophobicity of the investigated strains was very weak. The results clearly show the influence of AA and UA on the presence of P fimbriae and curli fibers, morphology of the UPECs cells and their adhesion to epithelium; however, some differences between activities of AA and UA were found. PMID:23132656

Dorota, Wojnicz; Marta, Kicia; Dorota, Tichaczek-Goska

2013-05-01

220

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

221

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

222

MicroRNA-200 Family Members Differentially Regulate Morphological Plasticity and Mode of Melanoma Cell Invasion  

PubMed Central

Background A functional role of microRNAs (miRNAs or miRs) in neoplasia and metastasis is becoming clear, and the miR-200 family has received much attention for potentially regulating tumor progression. The miRNAs of this family have been shown to suppress epithelial-mesenchymal transition, and their down-regulation in some tumors promotes invasion and metastasis. Interestingly, while miR-200 is down-regulated in some cancers, it is up-regulated in others. Principal Findings We show that levels of miR-200 are increased in melanoma cell lines compared to normal melanocytes and that miR-200 family members play a role in determining modes of tumor cell migration. Individual tumor cells can invade in either elongated, “mesenchymal-type” or rounded, “amoeboid-like” modes and these two modes of invasion are inter-convertible [1]. In melanoma cell lines, expression of miR-200 members does not suppress invasion but rather leads to a switch between modes of invasion. MicroRNA-200c results in a higher proportion of cells adopting the rounded, amoeboid-like mode of invasion, while miR-200a results in a protrusion-associated elongated mode of invasion. Functional target identification studies suggest that the morphological effects of miR-200c may be mediated by reduced expression of MARCKS, which has been linked to formation of cell protrusions. In contrast miR-200a reduces actomyosin contractility, a feature of rounded morphology. Significance Overall our findings call into question the general role of miR-200 in suppressing invasion and metastasis, and highlight novel distinguishing characteristics of individual miR-200 family members.

Elson-Schwab, Ilan; Lorentzen, Anna; Marshall, Christopher J.

2010-01-01

223

Mesoscale modeling of hydrated morphologies of 3M perfluorosulfonic acid-based fuel cell electrolytes.  

PubMed

Dissipative particle dynamics (DPD) simulations have been carried out to study the hydrated morphology of 3M perfluorosulfonic acid (PFSA) fuel cell membranes as a function of the equivalent weight (EW), molecular weight (MW), and hydration level. The 3M PFSA ionomers were modeled using typical EWs of 578, 640, and 790 g/mol, and molecular weights were varied from about 45,000 to 90,000 g/mol in order to be close to the experimental range. The morphology changes corresponding to the EW, MW, and hydration level were comparatively investigated by inspecting the water distributions, followed by quantitative analysis by radial distribution functions and Bragg spacing according to the periodicity of water domains. Compared to the morphologies of short-side-chain PFSA membrane (Wu, D.; Paddison, S. J.; Elliott, J. A. Macromolecules 2009, 42, 3358-3367), the longer side chain in 3M PFSA membrane provides more flexibility for the sulfonate-terminated side chains and generally results in the stronger aggregation of water clusters. This results in lower water uptake for higher EW, corresponding to a lower ion-exchange capacity (IEC), which is attributed experimentally to a higher crystallinity of the fluorocarbon phase, although our simulations were not able to observe the crystallites directly. PMID:20704341

Wu, Dongsheng; Paddison, Stephen J; Elliott, James A; Hamrock, Steven J

2010-09-01

224

Fractal morphology of Beta vulgaris L. cell suspension culture permeabilized with Triton X-100®  

NASA Astrophysics Data System (ADS)

In this work, morphology of Beta vulgaris L. cells permeabilized with 0.7mM of Triton X-100® was evaluated using digital image processing and concepts of fractal dimension (perimeter- area relations). Important morphometric changes were found when the contact-time with chemical agent was increased. The size of cells decreased, the cells lost the roundness and their shape was more sinuous; this behaviour was a result of a probable shrinkage caused by the excess of exposure with the permeabilization agent. Morphology of B. vulgaris cells after permeabilization, exhibited a fractal nature since the slope of the ratio of the logarithm of the perimeter vs logarithm of the area was higher than unit. Fractal geometry of the cell morphology was affected as a result of the exposure to Triton X-100®. Those changes can be attributed to the loss of turgor and structure of the cell wall.

Arenas-Ocampo, M.; Alamilla-Beltrán, L.; Vanegas-Espinoza, P. E.; Camacho-Díaz, B. H.; Campos-Mendiola, R.; Gutiérrez-López, G.; Jiménez-Aparicio, A.

2012-02-01

225

Morphological and proteomic analysis of early stage of osteoblast differentiation in osteoblastic progenitor cells.  

PubMed

Bone remodeling relies on a dynamic balance between bone formation and resorption, mediated by osteoblasts and osteoclasts, respectively. Under certain stimuli, osteoprogenitor cells may differentiate into premature osteoblasts and further into mature osteoblasts. This process is marked by increased alkaline phosphatase (ALP) activity and mineralized nodule formation. In this study, we induced osteoblast differentiation in mouse osteoprogenitor MC3T3-E1 cells and divided the process into three stages. In the first stage (day 3), the MC3T3-E1 cell under osteoblast differentiation did not express ALP or deposit a mineralized nodule. In the second stage, the MC3T3-E1 cell expressed ALP but did not form a mineralized nodule. In the third stage, the MC3T3-E1 cell had ALP activity and formed mineralized nodules. In the present study, we focused on morphological and proteomic changes of MC3T3-E1 cells in the early stage of osteoblast differentiation - a period when premature osteoblasts transform into mature osteoblasts. We found that mean cell area and mean stress fiber density were increased in this stage due to enhanced cell spreading and decreased cell proliferation. We further analyzed the proteins in the signaling pathway of regulation of the cytoskeleton using a proteomic approach and found upregulation of IQGAP1, gelsolin, moesin, radixin, and Cfl1. After analyzing the focal adhesion signaling pathway, we found the upregulation of FLNA, LAMA1, LAMA5, COL1A1, COL3A1, COL4A6, and COL5A2 as well as the downregulation of COL4A1, COL4A2, and COL4A4. In conclusion, the signaling pathway of regulation of the cytoskeleton and focal adhesion play critical roles in regulating cell spreading and actin skeleton formation in the early stage of osteoblast differentiation. PMID:20483354

Hong, Dun; Chen, Hai-Xiao; Yu, Hai-Qiang; Liang, Yong; Wang, Carrie; Lian, Qing-Quan; Deng, Hai-Teng; Ge, Ren-Shan

2010-08-15

226

Morphological and proteomic analysis of early stage of osteoblast differentiation in osteoblastic progenitor cells  

SciTech Connect

Bone remodeling relies on a dynamic balance between bone formation and resorption, mediated by osteoblasts and osteoclasts, respectively. Under certain stimuli, osteoprogenitor cells may differentiate into premature osteoblasts and further into mature osteoblasts. This process is marked by increased alkaline phosphatase (ALP) activity and mineralized nodule formation. In this study, we induced osteoblast differentiation in mouse osteoprogenitor MC3T3-E1 cells and divided the process into three stages. In the first stage (day 3), the MC3T3-E1 cell under osteoblast differentiation did not express ALP or deposit a mineralized nodule. In the second stage, the MC3T3-E1 cell expressed ALP but did not form a mineralized nodule. In the third stage, the MC3T3-E1 cell had ALP activity and formed mineralized nodules. In the present study, we focused on morphological and proteomic changes of MC3T3-E1 cells in the early stage of osteoblast differentiation - a period when premature osteoblasts transform into mature osteoblasts. We found that mean cell area and mean stress fiber density were increased in this stage due to enhanced cell spreading and decreased cell proliferation. We further analyzed the proteins in the signaling pathway of regulation of the cytoskeleton using a proteomic approach and found upregulation of IQGAP1, gelsolin, moesin, radixin, and Cfl1. After analyzing the focal adhesion signaling pathway, we found the upregulation of FLNA, LAMA1, LAMA5, COL1A1, COL3A1, COL4A6, and COL5A2 as well as the downregulation of COL4A1, COL4A2, and COL4A4. In conclusion, the signaling pathway of regulation of the cytoskeleton and focal adhesion play critical roles in regulating cell spreading and actin skeleton formation in the early stage of osteoblast differentiation.

Hong, Dun [Population Council, 1230 York Avenue, New York, NY 10065 (United States) [Population Council, 1230 York Avenue, New York, NY 10065 (United States); Orthopedic Department, Taizhou Hospital, Wenzhou Medical College, Linhai, Zhejiang 317000 (China); Chen, Hai-Xiao, E-mail: Hxchen-1@163.net [Orthopedic Department, Taizhou Hospital, Wenzhou Medical College, Linhai, Zhejiang 317000 (China)] [Orthopedic Department, Taizhou Hospital, Wenzhou Medical College, Linhai, Zhejiang 317000 (China); Yu, Hai-Qiang [Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States)] [Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Liang, Yong; Wang, Carrie [Population Council, 1230 York Avenue, New York, NY 10065 (United States)] [Population Council, 1230 York Avenue, New York, NY 10065 (United States); Lian, Qing-Quan [The 2nd Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325000 (China)] [The 2nd Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325000 (China); Deng, Hai-Teng, E-mail: dengh@mail.rockefeller.edu [Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States)] [Proteomics Resource Center, The Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States); Ge, Ren-Shan, E-mail: rge@popcbr.rockefeller.edu [Population Council, 1230 York Avenue, New York, NY 10065 (United States) [Population Council, 1230 York Avenue, New York, NY 10065 (United States); The 2nd Affiliated Hospital, Wenzhou Medical College, Wenzhou, Zhejiang 325000 (China)

2010-08-15

227

Automatic classification of cells using morphological shape in peripheral blood images  

Microsoft Academic Search

A novel technique for automatic analysis and classification of cells in peripheral blood images is presented. The purposes of this research are to analyze and classify morphological shapes of mature red-blood cells and white-blood cells in peripheral blood images. We first, identify red-blood cells and white-blood cells in a blood image captured from CCD camera attached to microscope. Feature extraction

KyungSu Kim; Jeongjun Song; Forouzan Golshani; Sethuraman Panchanathan

2000-01-01

228

Influence of extracellular matrix and collagen components on alveolar type 2 cell morphology and function  

Microsoft Academic Search

Summary  The effects of various extracellular matrices and collagenous components on the morphology, growth, and function of cultured\\u000a alveolar type 2 cells is examined. Cells grown on an endothelial matrix (EC) showed the greatest adherence, some cell division,\\u000a and spreading to reach confluence sooner than cells grown on an epithelial matrix or on various types of collagen. The attenuated\\u000a cells from

I. Y. R. Adamson; G. M. King; L. Young

1989-01-01

229

GD3 Expression in CHO-K1 Cells Increases Growth Rate, Induces Morphological Changes, and Affects Cell-Substrate Interactions  

Microsoft Academic Search

We have generated a panel of CHO-K1 cell clones with different glycolipid compositions by stable transfection of appropriate glycosyltransferases and studied the morphological and growth phenotype of a clone stably expressing Sial-T2. Compared with the GM3 expressing parental cells, Sial-T2 transfectants show low expression of GM3 and neo expression of GD3 and GT3. These cells show about 60% reduction of

Jose L. Daniotti; Adolfo R. Zurita; Vera M. T. Trindade; Hugo J. F. Maccioni

2002-01-01

230

Morphology of polymer\\/fullerene bulk heterojunction solar cells  

Microsoft Academic Search

Within the different organic photovoltaic devices the conjugated polymer\\/fullerene bulk heterojunction approach is one of the foci of today's research interest. These devices are highly dependent on the solid state nanoscale morphology of the two components (donor\\/acceptor) in the photoactive layer. The need for finely phase separated polymer-fullerene blends is expressed by the limited exciton diffusion length present in organic

Harald Hoppe; Niyazi Serdar Sariciftci

2006-01-01

231

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

232

Cell morphology in long-term cultures of normal and abnormal amniotic fluids.  

PubMed

The cell morphology of long-term cultures of amniotic fluid cells from 10 fetuses with a neural tube defect (NTD) and three with omphalocele was examined and compared to 30 long-term cultures of normal amniotic fluids as well as a long-term culture of human fetal brain. Cultures from the amniotic fluids of the fetuses with NTD and omphalocele showed cells with the same general characteristics as normal amniotic fluid cells. However, the cultures of amniotic fluid cells from NTD pregnancies had an additional cell type also seen in fetal brain culture. This was a neuroblast-like cell, with small rounded refractile morphology and long branching processes forming clusters of varying sizes which lay on top of large flat cells. These neuroblast-like cells diminished in number with time in culture and were not present in subcultures. Their possible neuronal origin is discussed. PMID:6179850

Medina-Gómez, P; Johnston, T H

1982-01-01

233

Characterization of lactate dehydrogenase isozyme pattern and morphology of three marine fish cell lines  

NASA Astrophysics Data System (ADS)

Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder ( Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch ( Lateolabrax japonicus) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream ( Pagrosomus major) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these three cell lines and their corresponding tissues of origin were investigated and compared. The results showed: (1) No difference was found in the LDH isozyme patterns of FG and flounder gill tissue. However, the LDH isozyme patterns of SPH and RSBF were significantly different from their corresponding tissues of origin; (2) LDH isozyme patterns of FG, SPH and RSBF were markedly different from each other and could serve as genetic markers for species identification and detection of cross contamination. Morphological change analysis of these three cell lines in comparison to their original tissues indicated that FG cells still appeared epithelioid without morphological transformation. However, morphological changes were found in SPH and RSBF compared to their original tissues. Therefore, the cellular morphology was still plastic in the relatively stable culture conditions, and it was possible that change of LDH patterns was related to morphological changes of fish cells in vitro.

Guo, Hua-Rong; Zhang, Shi-Cui; Li, Hong-Yan; Tong, Shang-Liang; Xiang, Jian-Hai

2002-09-01

234

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

235

Environmental factors affecting Galaxy Morphology - a study using COSMOS  

NASA Astrophysics Data System (ADS)

According to our current understanding, galaxy shapes and morphologies should depend on various factors such as the local environment. Realistic image simulations for calibration of weak lensing analysis methods that use training samples from the Hubble Space Telescope can therefore be affected by these trends, due to the limited volume of the universe that has been surveyed by Hubble. I will show how redshift slices in a volume-limited subsample of COSMOS can be classified as overdense or underdense (or neither), and how the statistical properties of various morphological parameters such as ellipticity, Sersic n, bulge-to-total ratio and color differ in these bins. This study requires a careful distinction between environment effects from large-scale structure, which we do not wish to include in simulations, and general trends in the galaxy population with redshift. We conclude with some guidance for how upcoming surveys can use COSMOS data as the basis for weak lensing simulations without having their conclusions overly affected by cosmic variance.

Jayaraman, Arun; Mandelbaum, Rachel; Lackner, Claire

2014-06-01

236

Electrophysiological and morphological characterization of the winter flounder mauthner cell  

Microsoft Academic Search

Flatfish (Pseudopleuronectes americanus) have Mauthner cells (M-cells) which are small as compared to certain other teleosts and behaviorally these fish display a suppression of a M-cell initiated startle response while on the substrate. They may depend on camouflage and, therefore, immobility in protection from predation. This ability to suppress the startle response could then be expressed in membrane properties of

Steven J. Zottoli

1981-01-01

237

Morphology assessment and fluorescence in situ hybridization of the same spermatozoon using a computerized cell-scanning system  

Microsoft Academic Search

BACKGROUND: Poor sperm morphology is statistically associated with an increase in the incidence of chromosome abnormalities. Our aim was to examine the possible correlation between chromosomal aberrations and sperm morphology in the same cell. METHODS: 12349 spermatozoa from 7 teratozoospermic and one globozoospermic patients, and from 3 fertile donors were analyzed using a system which scans for cell morphology and

D. Strassburger; M. Reichart; S. Kaufman; E. Kasterstein; D. Komarovsky; S. Friedler; M. Schachter; R. Ron-El; A. Raziel

2006-01-01

238

Morphological and immunohistochemical evaluation of ganglion cysts. Cross-sectional study of 354 cases.  

PubMed

The aim of this study was to characterize the morphology and immunophenotype of ganglion cysts (GCs) and explore their histogenetic origin. Material and Methods: A cross-sectional morphological and immunohistochemical study of 354 GCs used the following antibody panel: vimentin, specific actin, ?-actin, smooth-muscle actin, smoothelin, h-caldesmon, ?-catenin, desmin, calponin, podoplanin, keratins 5/6, E-cadherin, cyclooxygenase 2 (COX-2), lysozyme, CD10, CD31, CD33, CD34, CD68, Ki-67, and PCNA. Double-blind semi-quantitative analyses were conducted to evaluate the immunopositivity on a 4-point scale. Samples from 10 synovial membranes and 10 scapholunate ligaments were compared. GCs showed a hyalinized wall with mesenchymal spindle cells and were intensely positive for vimentin, actins, h-caldesmon, calponin in all cases and for podoplanin in 53% of cases, suggesting features of early muscle differentiation, without ruling out a myofibroblastic origin. Focal cavity lining of non-synovial flat or raised cells (CD34/CD31/CD10/E-cadherin-negative and podoplanin-positive in 34% of cases) was detected in 93% of cases, showing differential expression with synovial membrane and scapholunate ligament cells. Nuclear positivity for proliferative markers was observed in GC wall cells (258.1±255; 1019.3±316 positive cells/mm², Ki-67 and PCNA, respectively) but positivity for these markers was significantly lower (p?0.001 Mann Whitney U-test) in scapholunate ligament samples. Conclusion: In this first immunohistochemical study of GCs, focal cellular lining of the cavity was observed in almost all cases, and the immunophenotype was identical to that of GC wall cells. These cells are immunohistochemically different from synoviocytes and scapholunate ligament cells and show characteristics of myofibroblasts or mesenchymal cells undergoing early muscle differentiation. PMID:24142582

O'Valle, Francisco; Hernández-Cortés, Pedro; Aneiros-Fernández, José; Caba-Molina, Mercedes; Gómez-Morales, Mercedes; Cámara, Miguel; Payá, Jorge A; Aguilar, David; Del Moral, Raimundo G; Aneiros, José

2014-05-01

239

A morphological study on human lingual venous valves.  

PubMed

This study deals with the appearance, function and pathophysiological action of the lingual venous valve in the design of surgical tongue flaps and in analyzing inspection of the tongue. Thirty two adult cadavers were studied, of which 7 were corrosive cast specimens. The lingual v. is well supplied with venous valves which may be divided into 3 types morphologically: hemispherical, spherical, and hanging spherical. Venous valves are classified according to their structures: bivalves, monovalves, and venous cristae. The abundant venous valves of the tongue effectively prevent reflux of blood. Various factors that influence venous blood reflux in the head and neck can be observed, analysed and judged by inspection of the tongue; the design of the pedicle and the anastomotic position of tongue flap should comply with the positions and orientations of its venous valves. PMID:9706674

Shangkuan, H; Xinghai, W; Shizhen, Z; Zengxing, W; Shiying, J

1998-01-01

240

Mature plasma cells as indicator of better prognosis in multiple myeloma. New methodology for the assessment of plasma cell morphology  

Microsoft Academic Search

The relationship between plasmablastic cells and outcome in multiple myeloma (MM) has been established for nearly 15 years. But the assessment of these cells is not easy to perform and it allows the identification of only a small proportion of patients. We investigated the plasma cell morphology using a progressive evaluation of consecutive criteria: nucleolus, chromatin and nuclear-cellular ratio (N\\/C).

Jean E Goasguen; Marc Zandecki; Claire Mathiot; Jean-Marie Scheiff; Marie Bizet; Béatrice Ly-Sunnaram; Bernard Grosbois; Matthieu Monconduit; Jean-Louis Michaux; Thierry Facon

1999-01-01

241

Functional morphology of the salivary gland of the snail, Helix pomatia: a histochemical and immunocytochemical study.  

PubMed

Functional morphology of Helix pomatia salivary gland cells was studied at light microscopic level by using different histochemical methods. Three cell types could be demonstrated in the salivary gland: mucocytes, granular and vacuolated cells. The distribution and the number of the different cell types were different in active and inactive snails. In active feeding animals, dilatated interlobular salivary ducts were observed, which were never present in inactive ones. In active animals an additional cell type, the cystic cell could also be observed. Periodic acid Schiff staining revealed both mucuos and serous elements in the salivary gland. Furthermore, hematoxyline-eosin staining indicated the occurrence of a cell layer with high mitotic activity in the acini. Applying immunohistochemical methods with monoclonal mouse anti-human Ki-67 clone, B56 and polyclonal rabbit anti-human Ki-67 antibodies, we also were able to demonstrate the occurrence of dividing cells in the salivary gland. Analysis of 1-2 microm semi-thin Araldite sections stained with toluidine-blue showed that the saliva can be released, in addition to possible exocytosis, by the lysis of cystic cells. Using an apoptosis kit, we could also establish that this process was due to rather an apoptotic than a necrotic mechanism. In the salivary gland of active snails, where an intensive salivation takes place, significantly more apoptotic cells occurred, if compared to that of inactive animals. It is suggested that programmed cell death may also be involved in the saliva release. PMID:15270238

Pirger, Zs; Elekes, K; Kiss, T

2004-01-01

242

Substrate-dependent modulation of 3D spheroid morphology self-assembled in mesenchymal stem cell-endothelial progenitor cell coculture.  

PubMed

The structural evolution of three-dimensional spheroids self-assembled from two different types of cells on selective biomaterials is demonstrated in this study. The two types of cells involved in the self-assembly are human mesenchymal stem cells (MSCs) and endothelial progenitor cells (EPCs). When seeded in different population ratios, they can create a variety of cellular patterns on different biomaterial substrates. When the two populations are matched in initial numbers, they are self-assembled in co-spheroids with different morphologies (i.e. randomly mixed, bumped, or concentric spheroids). The morphologies are influenced by the specific cell-substrate interaction possibly through integrin signaling, as well as a substrate-dependent regulation of heterophilic cell-cell interaction possibly through Notch signaling. In particular, the self-assembled core-shell concentric spheroids from adipose-derived MSCs and EPCs show a greater angiogenic effect in vitro. This study reveals the possibility to modulate the self-assembled morphology as well as the effect of cocultured cells by changing the cell culture substratum. PMID:24909102

Hsu, Shan-Hui; Ho, Tung-Tso; Huang, Nien-Chi; Yao, Chao-Ling; Peng, Luen-Hau; Dai, Niann-Tzyy

2014-08-01

243

Histopathologic diagnosis of lymphomatous versus inflammatory erythroderma: a morphologic and phenotypic study on 47 skin biopsies.  

PubMed Central

Erythroderma may reveal a cutaneous T cell lymphoma (CTCL) and various erythrodermic inflammatory dermatoses (EID), and histopathological diagnosis is often difficult. The aim of this study was to determine whether morphological parameters, ?-catenin and JunB, previously shown to be expressed by CTCL cells, the epidermal CD8:CD3 ratio, and CD30 expression may help for histopathological diagnosis of erythroderma, especially for the differential diagnosis between lymphomas and EID. We retrospectively reviewed a series of 47 skin biopsies from patients with erythroderma (18 CTCL and 29 EID). Etiological diagnosis in each case was established using all clinical, biological and histopathological results. At global blinded assessment of HES stained slides, a correct diagnosis of the underlying cause of erythroderma was made using only morphologic criteria in 31% of cases. A correct differential diagnosis between lymphoma and EID was done with certainty in 57% of cases. Various morphologic and phenotypic parameters were then recorded and we compared their frequency in the CTCL versus the EID group. With the exception of atypical lymphocytes, the moderate to high density of dermal infiltrates and Pautrier’s microabcesses, only found in CTCL, no morphologic parameter was found to be specific of CTCL, although single lymphocytes epidermotropism, telangiectasias and slight lymphocytic dermal infiltrate were significantly more frequent in EID. A low (<10%) CD8:CD3 ratio in the epidermal lymphocytic infiltrate and dermal CD30+ lymphocytes were significantly more frequent in CTCL. JunB expression by lymphocytes was specific of CTCL, but was inconstant in our series (17%). We found ?-catenin expression in a minority of cases from both the CTCL and EID groups. Among EID, dermal suprapapillary thinning was specific of psoriasis. Neutrophils exocytosis and edema of papillary dermis were significantly more frequent in psoriasis, and spongiosis was more frequent in eczema. In conclusion, few morphological and phenotypical parameters are helpful in making a differential diagnosis between erythrodermic CTCL and EID using paraffin embedded skin biopsies.

Ram-Wolff, Caroline; Martin-Garcia, Nadine; Bensussan, Armand; Bagot, Martine; Ortonne, Nicolas

2010-01-01

244

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

245

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

246

Morphological study of the inferior transverse scapular ligament.  

PubMed

The suprascapular nerve can be compressed by the inferior transverse scapular ligament (ITSL), also known as the spinoglenoid ligament, and this entrapment results in dysfunction of the external rotation of the upper arm owing to isolated weakness of the infraspinatus muscle. The morphology of the ITSL has not been adequately characterized. The aim of this study was to clarify the morphological characteristics of the ITSL. In total, 110 shoulders from 72 cadavers were dissected in this study. The ITSL was present in 73 (66.4%) of the 110 specimens, and comprised membrane in 40 (36.4%), ligament in 25 (22.7%), and both membrane and ligament in eight (7.3%). This structure could be classified into three types on the basis of its shape: band-like (33.6%, type I), triangular (15.5%, type II), or irregular (17.3%, type III). In the spinoglenoid notch, the suprascapular nerve was always close to the lateral margin of the scapular spine. The length of the ligament between its origin and insertion sites ranged from 8.7 to 23.4?mm at its superior margin and from 8.9 to 17.5?mm at its inferior margin. The ligament width and thickness at its midportion ranged from 1.6 to 10.0?mm and from 0.1 to 1.2 mm, respectively. The results of this study improve understanding of the ITSL and will be helpful for successful diagnoses and treatments for selective suprascapular nerve entrapment. Clin. Anat. 27:707-711, 2014. © 2013 Wiley Periodicals, Inc. PMID:23813778

Won, Hyung-Jin; Won, Hyung-Sun; Oh, Chang-Seok; Han, Seung-Ho; Chung, In-Hyuk; Yoon, Young Cheol

2014-07-01

247

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.

Sobel, Burton E.; Budd, Ralph C.

2007-01-01

248

Massive obesity and the kidney. A morphologic and statistical study.  

PubMed Central

The renal morphology of 5 grossly obese patients with normal renal function and many of the features of the Pickwickian syndrome was studied at autopsy. The most striking feature was that of increased glomerular size. Measurements of two parameters of glomerular areas indicated statistically significant glomerular enlargement for both as compared to controls. Glomerulomegaly was primarily the result of vascular dilatation and a variable mesangial component. This abnormality was related to several factors, including increased blood volume, hypoxia, and increased right ventricular pressure. Polycythemia, commonly noted in other similar conditions with glomerulomegaly, is believed to be of no importance in the pathogenesis of glomerular enlargement. Images Figure 3-6 Figure 1 Figure 2

Cohen, A. H.

1975-01-01

249

The acetabular point: a morphological and ontogenetic study  

PubMed Central

The acetabular point was analysed by studying human pelvic bones from 326 individuals ranging from newborns to age 97 y. The bones were categorised into 3 groups according to the degree of fusion for the 3 elements of the pelvis: nonfused (59), semifused (5) and fused (262). The acetabular point in immature pelvic bones is clearly represented by the point of the fusion lines for each bony element at the level of the acetabular fossa. In adult pelvic bones the acetabular fossa has an irregular clover-leaf shape, the superior lobe being smaller than the anterior and posterior lobes. Cross-sectional analysis of acetabular morphology suggested that the acetabular point in adult pelvic bones is always represented by the indentation between the superior and the anterior lobes of the acetabular fossa.

RISSECH, C.; SANUDO, J. R.; MALGOSA, A.

2001-01-01

250

The acetabular point: a morphological and ontogenetic study.  

PubMed

The acetabular point was analysed by studying human pelvic bones from 326 individuals ranging from newborns to age 97 y. The bones were categorised into 3 groups according to the degree of fusion for the 3 elements of the pelvis: nonfused (59), semifused (5) and fused (262). The acetabular point in immature pelvic bones is clearly represented by the point of the fusion lines for each bony element at the level of the acetabular fossa. In adult pelvic bones the acetabular fossa has an irregular clover-leaf shape, the superior lobe being smaller than the anterior and posterior lobes. Cross-sectional analysis of acetabular morphology suggested that the acetabular point in adult pelvic bones is always represented by the indentation between the superior and the anterior lobes of the acetabular fossa. PMID:11465866

Rissech, C; Sañudo, J R; Malgosa, A

2001-06-01

251

Morphology and distribution of Müller cells in the retina of the toad Bufo marinus.  

PubMed

We have previously shown that an antibody against neuron-specific enolase (NSE) selectively labels Müller cells (MCs) in the anuran retina (Wilhelm et al. 1992). In the present study the light- and electron-microscopic morphology of MCs and their distribution were described in the retina of the toad, Bufo marinus, using the above antibody. The somata of MCs were located in the proximal part of the inner nuclear layer and were interconnected with each other by their processes. The MCs were uniformly distributed across the retina with an average density of 1500 cells/mm2. Processes of MCs encircled the somata of photoreceptor cells isolating them from each other by glial sheath, except for those of the double cones. Some of the photoreceptor pedicles remained free of glial sheath. Electron-microscopic observations confirmed that MC processes provide an extensive scaffolding across the neural retina. At the outer border of the ganglion cell layer these processes formed a non-continuous sheath. The MC processes traversed through the ganglion cell layer and spread beneath it between the neuronal somata and the underlying optic axons. These processes formed a continuous inner limiting membrane separating the optic fibre layer from the vitreous tissue. Neither astrocytic nor oligodendrocytic elements were found in the optic fibre layer. The significance of the uniform MC distribution and the functional implications of the observed pattern of MC scaffolding are discussed. PMID:8481951

Gábriel, R; Wilhelm, M; Straznicky, C

1993-04-01

252

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.

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

2013-01-01

253

Molecular Dynamic Simulation: Morphology Study of Organic Photovoltaic Thin Film  

NASA Astrophysics Data System (ADS)

Engineering heterodyne junction solar cells requires precise positioning of the photoactive polymers and the PCBM conductors such that maximum current reaches the electrodes with minimal resistive scattering. One possible method for accomplishing this may be to use polymer phase segregation in combination with the nanoparticles' natural segregation to the interfaces. In this manner, large-scale devices can be formed using self-assembly methods, rather than fixed methods. We have used Molecular Dynamics simulation to predict the morphology of polymer blends and determine which combination of factors would yield the optimal cylindrical pattern, which would contact the electrodes, while producing the largest number of interfaces. Secondly, we were also able to determine the conditions that would cause the particles to segregate and template along the interfaces, which would provide direct conductivity to the electrodes. Using thin film and bulk structures and by manipulating particle size, the attraction between the particle and the polymer component, and the amount of filler within the material, we can explore the formation of cheaper, more effective and efficient networks.

Xu, Di

254

Polyelectrolyte multilayer coated nanofibrous mats: Controlled surface morphology and cell culture  

Microsoft Academic Search

We reported the controlled surface morphologies and the cell culture of polyelectrolyte multilayer coated nylon 6 fibrous\\u000a mats with different number of layers. Polyelectrolyte multilayer coated nylon 6 fibers were successfully prepared by an alternative\\u000a deposition of alginic acid sodium salt and chitosan via a Layer-by-Layer (LbL) electrostatic self-assembly. The surface morphology,\\u000a stiffness, and hydrophilicity of polyelectrolyte multilayer coated nylon

Jong Hoon Park; Byoung Suhk Kim; Hyun Jin Tae; In Shik Kim; Hak Yong Kim; Myung Seob Khi

2009-01-01

255

Dynamics Study on Morphological Stabilities of Cellular Crystal Lateral Wall  

NASA Astrophysics Data System (ADS)

The lateral wall stabilities during the growing process of cellular crystal in the melt were studied in this article. The dynamics equation of cylindrical solid-liquid interface morphological stabilities in melt was first derived, and then the expression of criterion for cylindrical solid-liquid interface morphological stabilities was defined. The effect of the shape factor, solid radius, and other relevant factors on the morphological stabilities was analyzed. Also, the critical shape factor and critical growth rate for keeping the stabilities of the interface were determined. The phenomenon during the lateral growth process of ?-phase cellular crystal in carbon steel was observed under a high-temperature confocal scanning laser microscope (HTCSLM), which was used to verify the theoretical analysis and calculated results. The results indicate that the shape factor is beneficial to improving the stabilities of the cellular crystal lateral wall. During the increase process of the cellular crystal radius, however, there is a certain value of the cellular crystal radius, which induces the shape factor to reduce stabilities of the cellular crystal lateral wall rapidly. Even if the other conditions are unchanged, the shape of the cellular crystal may also cause the cellular crystal lateral wall to lose its stabilities. There are two critical growth rates to keep the cellular crystal lateral wall growing stably under the conditions of this research. For the Fe-0.15 pct C-0.8 pct Mn alloy, these two critical growth rates are 10-4 and 10 cm/s orders of magnitude, respectively. The difference between them is more than 105 times, so the slow critical growth rate conforms to the actual critical growth rate. The radius of the cellular crystal is the main influencing factor of lateral wall stabilities. The bigger the radius of the cellular crystal is, the worse the stabilities of the lateral wall are. That is also one of the reasons that the fine cellular crystal can survive during a certain period. The results of the theoretical analysis about stabilities of the cellular crystal lateral wall agree well with the lateral growth phenomena of ? phase cellular crystal in carbon steel observed by a HTCSLM. The theoretically calculated results of the radial critical growth rates are coincident with the experimental results.

Chang, Guowei; Chen, Shuying; Li, Qingchun; Yue, Xudong; Jin, Guangcan

2012-06-01

256

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.

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

2009-01-01

257

Melt Extruded Open-Cell Microcellular Foams for Membrane Separation: Processing and Cell Morphology Relationship  

Microsoft Academic Search

This paper presents an experimental study on the manufacture of microcellular polycarbonate in a designed co-rotating twin-screw extrusion system using CO2 as a blowing agent. Open-cell microcellular polycarbonate foams in the form of hollow fiber were produced with a cell density on the order of 109-1010 cell\\/cm3 and an average cell size in the range of 5-10 &mgr;m. The effects

Quan Huang; Bernd Seibig; Dieter Paul

2000-01-01

258

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

PubMed Central

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 expressing active PBP 5 produced cells of normal shape, while mutants lacking PBP 5 produced cells with altered diameters, contours, and topological features. These morphological effects were visible in untreated cells, but the defects were exacerbated in cells forced to filament by inactivation of PBP 3 or FtsZ. After filamentation, cellular diameter varied erratically along the length of individual filaments and many filaments exhibited extensive branching. Also, in general, the mean diameter of cells lacking PBP 5 was significantly increased compared to that of cells from isogenic strains expressing active PBP 5. Expression of cloned PBP 5 reversed the effects observed in ?dacA mutants. Although deletion of PBP 5 was required for these phenotypes, the absence of additional PBPs magnified the effects. The greatest morphological alterations required that at least three PBPs in addition to PBP 5 be deleted from a single strain. In the extreme cases in which six or seven PBPs were deleted from a single mutant, cells and cell filaments expressing PBP 5 retained a normal morphology but cells and filaments lacking PBP 5 were aberrant. In no case did mutation of another PBP produce the same drastic morphological effects. We conclude that among the low-molecular-weight PBPs, PBP 5 plays a principle role in determining cell diameter, surface uniformity, and overall topology of the peptidoglycan sacculus.

Nelson, David E.; Young, Kevin D.

2000-01-01

259

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.

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

2014-01-01

260

The observation report of red blood cell morphology in Thailand teenager by using data mining technique.  

PubMed

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

261

Morphological and neoplastic transformation of C3H/10T1/2 Cl 8 mouse embryo cells by insoluble carcinogenic nickel compounds  

SciTech Connect

The authors studied induction of cytotoxicity and morphological transformation in C3H/10T1/2 Cl8 (10T1/2) mouse embryo fibroblasts by soluble and insoluble carcinogenic nickel compounds. Soluble nickel sulfate and nickel chloride caused dose-dependent cytotoxicity after 48 hr treatments, but neither compound induced morphological transformation even at concentrations causing up to 94% cytotoxicity. In soluble nickel subsulfide, nickel monosulfide, and nickel oxide caused dose-dependent cytotoxicity and a low, dose-dependent frequency of morphological transformation after 48 hr exposure of cells to these compounds. Foci were predominantly of type II morphology; type III foci were rare. The insoluble nickel compounds studied caused no induction of base substitution mutations to ouabain resistance in 10T1/2 cells over concentration ranges that induced morphological transformation. They twice cloned type II and type III foci induced by insoluble nickel compounds, established independent cell lines, and characterized their phenotypes. These data indicate that insoluble carcinogenic nickel compounds induced type II foci in 10T1/2 cells, some of which were tumorigenic, and that the 10T1/2 cell system is suitable for studying mechanisms of nickel compound-induced morphological transformation in mammalian cells.

Miura, T.; Patierno, S.R.; Sakuramoto, T.; Landolph, J.R. (Univ. of Southern California School of Medicine, Los Angeles (USA))

1989-01-01

262

Morphological and genetic studies of waterlogged Prunus species from the Roman vicus Tasgetium (Eschenz, Switzerland)  

Microsoft Academic Search

Morphological and genetic studies were performed on waterlogged Prunus fruit stones from the Roman vicus Tasgetium (Eschenz, Switzerland). Some fruit stones could be identified to species level based on morphological and metric criteria. Other fruit stones found were not identifiable to species level. Of the latter, the morphological group Prunus insititia\\/spinosa represents either native sloe, cultivated primitive plum (damson) or

Britta Pollmann; Stefanie Jacomet; Angela Schlumbaum

2005-01-01

263

Imaging organic solar cell morphology with organic light emitting diode-organic solar cell devices  

NASA Astrophysics Data System (ADS)

Organic solar cell (OSC)-organic light emitting Diode (OLED) stacked structures are investigated for their use in imaging the morphology of the bulk heterojunction layer used in OSCs. In lieu of the top cathode, bilayer OLED devices can be deposited directly on top of the otherwise traditional OSC device. Design considerations and device optimization are detailed. Results show that the bulk heterojunction layer composed of a blend of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) is sufficiently hole-conductive to allow for reasonably strong emission, peaking at a brightness of 175 cd/m2 at a driving voltage of 8.5V and a current density of 12.5mA/cm2. Since the OLED is in intimate contact with the P3HT:PCBM layer, it provides enhanced images of the bulk heterojunction with information on macro-scale defects and morphological variations. By tuning the emission intensity, detailed images can be obtained without the need for overly sensitive or costly cameras. Further applications of this technique, such as its potential in testing new donor polymer formulations as well as its capacity to monitor degradation due to residual solvents, are briefly discussed.

Williams, Graeme; Aziz, Hany

2012-09-01

264

Morphology of spheroidal hepatocytes within injectable, biodegradable, and thermosensitive poly(organophosphazene) hydrogel as cell delivery vehicle.  

PubMed

An aggregate of specific cells is often regarded as a better form of single-cell in artificial organs and mammalian cell bioreactors for improved cell-specific functions. In this study, freshly harvested primary rat hepatocytes, cultivated as spheroids and entrapped in a synthetic thermoreversible extracellular matrix, were examined for differentiation morphology and enhanced liver-specific functions and compared with a control set (single-cell hepatocytes). A copolymer of poly(organophsophazene) hydrogel, an injectable, biodegradable, and thermosensitive matrix, was used to entrap hepatocytes as spheroids or single cells. In a 28-d culture period, the spheroidal hepatocytes maintained a higher viability and produced albumin and urea at constant rates, whereas the single hepatocytes showed a reduction in the level of albumin secretion in the hydrogel. The culturing of spheroidal hepatocytes is a potentially useful three-dimensional cell system for application in bioartificial liver devices and bioreactors. PMID:16716925

Park, Keun-Hong; Song, Soo Chang

2006-03-01

265

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

266

Morphologic and Gene Expression Criteria for Identifying Human Induced Pluripotent Stem Cells  

PubMed Central

Induced pluripotent stem (iPS) cells can be generated from somatic cells by the forced expression of four factors, Oct3/4, Sox2, Klf4, and c-Myc. While a great variety of colonies grow during induction, only a few of them develop into iPS cells. Researchers currently use visual observation to identify iPS cells and select colonies resembling embryonic stem (ES) cells, and there are no established objective criteria. Therefore, we exhaustively analyzed the morphology and gene expression of all the colonies generated from human fibroblasts after transfection with four retroviral vectors encoding individual factors (192 and 203 colonies in two experiments) and with a single polycistronic retroviral vector encoding all four factors (199 and 192 colonies in two experiments). Here we demonstrate that the morphologic features of emerged colonies can be categorized based on six parameters, and all generated colonies that could be passaged were classified into seven subtypes in colonies transfected with four retroviral vectors and six subtypes with a single polycistronic retroviral vector, both including iPS cell colonies. The essential qualifications for iPS cells were: cells with a single nucleolus; nucleus to nucleolus (N/Nls) ratio ?2.19: cell size ?43.5 µm2: a nucleus to cytoplasm (N/C) ratio ?0.87: cell density in a colony ?5900 cells/mm2: and number of cell layer single. Most importantly, gene expression analysis revealed for the first time that endogenous Sox2 and Cdx2 were expressed specifically in iPS cells, whereas Oct3/4 and Nanog, popularly used markers for identifying iPS cells, are expressed in colonies other than iPS cells, suggesting that Sox2 and Cdx2 are reliable markers for identifying iPS cells. Our findings indicate that morphologic parameters and the expression of endogenous Sox2 and Cdx2 can be used to accurately identify iPS cells.

Wakao, Shohei; Kitada, Masaaki; Kuroda, Yasumasa; Ogura, Fumitaka; Murakami, Toru; Niwa, Akira; Dezawa, Mari

2012-01-01

267

Morphological and biochemical characterization of Erwinia amylovora-induced hypersensitive cell death in apple leaves.  

PubMed

In attached apple leaves, spot-inoculated with Erwinia amylovora, the phenotypic appearance of the hypersensitive response (HR) and the participation of ethylene, reactive oxygen species (ROS) and of vacuolar processing enzyme (VPE) (a plant caspase-1-like protease) were analysed. The HR in both the resistant and susceptible genotypes expressed a similar pattern of distinguishable micro HR lesions that progressed into confined macro HR lesions. The HR symptoms in apple were compared to those in non-host tobacco. The morphology of dead cells (protoplast shrinkage and retraction from cell wall) in apple leaves resembled necrotic programmed cell death (PCD). Lesion formation in both cv. Free Redstar (resistant) and cv. Idared (highly susceptible) was preceded by ROS accumulation and elevation of ethylene levels. Treatment of infected leaves with an inhibitor of ethylene synthesis led to a decrease of ethylene emission and suppression of lesion development in both cultivars. In the resistant but not in the susceptible apple cultivar an early and late increase in VPE gene expression was detected. This suggests that VPE might be an underlying component of the response to E. amylovora in resistant apple cultivars. The findings show that in the studied pathosystem the cell death during the HR proceeds through a signal transduction cascade in which ROS, ethylene and VPE pathways play a role. PMID:23321023

Iakimova, Elena T; Sobiczewski, Piotr; Michalczuk, Lech; W?grzynowicz-Lesiak, El?bieta; Mikici?ski, Artur; Woltering, Ernst J

2013-02-01

268

Morphological changes induced by advanced glycation endproducts in osteoblastic cells: effects of co-incubation with alendronate.  

PubMed

Advanced glycation endproducts (AGEs) accumulate with age in various tissues, and are further increased in patients with Diabetes mellitus, in which they are believed to contribute to the development and progression of chronic complications that include a decrease in bone quality. Bisphosphonates are anti-osteoporotic drugs that have been used for the treatment of patients with diabetic bone alterations, although with contradictory results. In the present study, we have evaluated the in vitro alterations on osteoblastic morphology by environmental scanning electron microscopy, in actin cytoskeleton and apoptosis induced by AGEs, as well as the modulation of these effects by alendronate (an N-containing bisphosphonate). Our present results provide evidence for disruption induced by AGEs of the osteoblastic actin cytoskeleton (geodesic domes) and significant alterations in cell morphology with a decrease in cell-substratum interactions leading to an increase in apoptosis of osteoblasts and a decrease in osteoblastic proliferation. High concentrations of alendronate (10(-5)M, such as could be expected in an osteoclastic lacuna) further increase osteoblastic morphological and cytoskeletal alterations. However, low doses of alendronate (10(-8)M, compatible with extracellular fluid levels to which an osteoblast could be exposed for most of its life cycle) do not affect cell morphology, and in addition are able to prevent AGEs-induced alterations and consequently apoptosis of osteoblasts. PMID:23465485

Gangoiti, María Virginia; Anbinder, Pablo Sebastián; Cortizo, Ana María; McCarthy, Antonio Desmond

2013-09-01

269

Clear cell carcinoma of the bladder in a patient with a earlier clear cell renal cell carcinoma: a case report with morphologic, immunohistochemical, and cytogenetical analysis.  

PubMed

Clear cell transitional carcinoma of the bladder is a subtype of transitional carcinoma that morphologically resembles a clear cell renal cell carcinoma. Although kidney tumors do not frequently metastasize to the bladder, the recurrence after a clear cell renal cell carcinoma has been reported even several years after nephrectomy. We report the case of a male patient to whom radical nephrectomy for a clear cell renal cell carcinoma has been done, with a bladder tumor featuring polygonal cells with abundant clear cytoplasm deeply infiltrating the vesical wall. We discuss the morphologic features, the immunohistochemical staining with a new marker and the UroVysion FISH analysis to achieve a definitive diagnosis. PMID:20216403

Rotellini, Matteo; Fondi, Cristina; Paglierani, Milena; Stomaci, Niceta; Raspollini, Maria Rosaria

2010-07-01

270

Promyelocytic Leukemia (PML) Protein Plays Important Roles in Regulating Cell Adhesion, Morphology, Proliferation and Migration  

PubMed Central

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.

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

271

Influence of levamisole and other angiogenesis inhibitors on angiogenesis and endothelial cell morphology in vitro.  

PubMed

Angiogenesis, the formation of new blood vessels from existing vessels is required for many physiological processes and for growth of solid tumors. Initiated by hypoxia, angiogenesis involves binding of angiogenic factors to endothelial cell (EC) receptors and activation of cellular signaling, differentiation, migration, proliferation, interconnection and canalization of ECs, remodeling of the extracellular matrix and stabilization of newly formed vessels. Experimentally, these processes can be studied by several in vitro and in vivo assays focusing on different steps in the process. In vitro, ECs form networks of capillary-like tubes when propagated for three days in coculture with fibroblasts. The tube formation is dependent on vascular endothelial growth factor (VEGF) and omission of VEGF from the culture medium results in the formation of clusters of undifferentiated ECs. Addition of angiogenesis inhibitors to the coculture system disrupts endothelial network formation and influences EC morphology in two distinct ways. Treatment with antibodies to VEGF, soluble VEGF receptor, the VEGF receptor tyrosine kinase inhibitor SU5614, protein tyrosine phosphatase inhibitor (PTPI) IV or levamisole results in the formation of EC clusters of variable size. This cluster morphology is a result of inhibited EC differentiation and levamisole can be inferred to influence and block VEGF signaling. Treatment with platelet factor 4, thrombospondin, rapamycin, suramin, TNP-470, salubrinal, PTPI I, PTPI II, clodronate, NSC87877 or non-steriodal anti-inflammatory drugs (NSAIDs) results in the formation of short cords of ECs, which suggests that these inhibitors have an influence on later steps in the angiogenic process, such as EC proliferation and migration. A humanized antibody to VEGF is one of a few angiogenesis inhibitors used clinically for treatment of cancer. Levamisole is approved for clinical treatment of cancer and is interesting with respect to anti-angiogenic activity in vivo since it inhibits ECs in vitro with a morphology resembling that obtained with antibodies to VEGF. PMID:24202320

Friis, Tina; Engel, Anne-Marie; Bendiksen, Christine D; Larsen, Line S; Houen, Gunnar

2013-01-01

272

Influence of Levamisole and Other Angiogenesis Inhibitors on Angiogenesis and Endothelial Cell Morphology in Vitro  

PubMed Central

Angiogenesis, the formation of new blood vessels from existing vessels is required for many physiological processes and for growth of solid tumors. Initiated by hypoxia, angiogenesis involves binding of angiogenic factors to endothelial cell (EC) receptors and activation of cellular signaling, differentiation, migration, proliferation, interconnection and canalization of ECs, remodeling of the extracellular matrix and stabilization of newly formed vessels. Experimentally, these processes can be studied by several in vitro and in vivo assays focusing on different steps in the process. In vitro, ECs form networks of capillary-like tubes when propagated for three days in coculture with fibroblasts. The tube formation is dependent on vascular endothelial growth factor (VEGF) and omission of VEGF from the culture medium results in the formation of clusters of undifferentiated ECs. Addition of angiogenesis inhibitors to the coculture system disrupts endothelial network formation and influences EC morphology in two distinct ways. Treatment with antibodies to VEGF, soluble VEGF receptor, the VEGF receptor tyrosine kinase inhibitor SU5614, protein tyrosine phosphatase inhibitor (PTPI) IV or levamisole results in the formation of EC clusters of variable size. This cluster morphology is a result of inhibited EC differentiation and levamisole can be inferred to influence and block VEGF signaling. Treatment with platelet factor 4, thrombospondin, rapamycin, suramin, TNP-470, salubrinal, PTPI I, PTPI II, clodronate, NSC87877 or non-steriodal anti-inflammatory drugs (NSAIDs) results in the formation of short cords of ECs, which suggests that these inhibitors have an influence on later steps in the angiogenic process, such as EC proliferation and migration. A humanized antibody to VEGF is one of a few angiogenesis inhibitors used clinically for treatment of cancer. Levamisole is approved for clinical treatment of cancer and is interesting with respect to anti-angiogenic activity in vivo since it inhibits ECs in vitro with a morphology resembling that obtained with antibodies to VEGF.

Friis, Tina; Engel, Anne-Marie; Bendiksen, Christine D.; Larsen, Line S.; Houen, Gunnar

2013-01-01

273

Morphologic characteristics of processes of nucleus pulposus cells in adult human intervertebral disc  

NASA Astrophysics Data System (ADS)

To explore morphologic characterizatics of cellular processes from adult human nucleus pulposus cells, the nucleus pulposus of adult human intervertebral disc were obtained from 8 patients (Thompson's grade I~II) and then the tissues specimens were carried out by frozen section and electron microscopic section as well as cell isolation and cultured, processes of nucleus pulposus cells were examined using light microscopy, laser scanning confocal microscopy and transmission electron microscopy. When examined at both the confocal and electron microscope level, all the cells possessed the processes and adjacent nucleus pulposus cells processes possessed a gap junction. But elongated and round cells can be examined when NP cells were monolayer cultured. The rate of elongated cells to round cells is 2.3 to 1. The elongated cells protrude along with the long axis of cell body without second processes. Dendritic processes of round cells protrude to all directions from the cell body with multiple-level processes. Processes are one of the morphologic characteristics of intervertebral disc cells which are different from articular cartilage chondrocytes. The research on processes functions will be helpful to understand pathomechanism of intervertebral disc degradation and open a new approach for cytobiology treatment of the intervertebral disc diseases.

Liu, Xiaoyun; Wu, Xinghuo; Hui, Liu; Xu, Weihua; Liu, Xianze; Yang, Shuhua

2008-12-01

274

Preparation, structural and morphological studies of Ni doped titania nanoparticles.  

PubMed

TiO2 nanoparticles doped with different weight percentages (4%, 8%, 12% and 16%) of nickel contents were prepared by a modified sol-gel method using Titanium tetra iso propoxide and nickel nitrate as precursors and 2-propanol as a solvent. X-ray diffraction studies show that the as prepared and annealed products show anatase structure with average particle sizes running between of 8 and 16nm. FTIR results demonstrate the presence of strong chemical bonding at the interface of TiO2 nanoparticles. The optical properties of bare and doped samples were carried out using UV-DRS and photoluminescence measurements. The surface morphology and the element constitution of the nickel doped TiO2 nanoparticles were studied by scanning electron microscope attached with energy dispersive X-ray spectrometer arrangement. The non linear optical properties of the products were confirmed by Kurtz second harmonic generation (SHG) test and the output power generated by the nanoparticle was compared with that of potassium di hydrogen phosphate (KDP). PMID:24667428

Rajamannan, B; Mugundan, S; Viruthagiri, G; Shanmugam, N; Gobi, R; Praveen, P

2014-07-15

275

Preparation, structural and morphological studies of Ni doped titania nanoparticles  

NASA Astrophysics Data System (ADS)

TiO2 nanoparticles doped with different weight percentages (4%, 8%, 12% and 16%) of nickel contents were prepared by a modified sol-gel method using Titanium tetra iso propoxide and nickel nitrate as precursors and 2-propanol as a solvent. X-ray diffraction studies show that the as prepared and annealed products show anatase structure with average particle sizes running between of 8 and 16 nm. FTIR results demonstrate the presence of strong chemical bonding at the interface of TiO2 nanoparticles. The optical properties of bare and doped samples were carried out using UV-DRS and photoluminescence measurements. The surface morphology and the element constitution of the nickel doped TiO2 nanoparticles were studied by scanning electron microscope attached with energy dispersive X-ray spectrometer arrangement. The non linear optical properties of the products were confirmed by Kurtz second harmonic generation (SHG) test and the output power generated by the nanoparticle was compared with that of potassium di hydrogen phosphate (KDP).

Rajamannan, B.; Mugundan, S.; Viruthagiri, G.; Shanmugam, N.; Gobi, R.; Praveen, P.

2014-07-01

276

Effect of a newly synthesized Zn sulfophthalocyanine derivative on cell morphology, viability, proliferation, and cytotoxicity in a human lung cancer cell line (A549).  

PubMed

Photodynamic therapy (PDT) is a photochemotherapeutic process that is used for the treatment of cancer. Photofrin is the most widely used photosensitizer, however, the chemical composition of Photofrin is unclear and it has a low absorption in the therapeutic wavelength (600-900 nm). This factor has stimulated research in synthesis and testing of new photosensitizers. This in vitro study evaluated the effectiveness of a Zn sulfophthalocyanine (ZnPcS(mix)) as a potential photosensitizer in the treatment of human lung cancer. Lung cancer cells (A549) were divided into four groups: group 1 was control cells receiving neither light nor drug; group 2 was light control for cells exposed to laser irradiation at a fluence of 4.98 J/cm(2); group 3 was drug control for cells incubated with 15.8 ?M photosensitizer and not exposed to laser irradiation, while group 4 was cells receiving the experimental treatment with 15.8 ?M photosensitizer and irradiation with 4.98 J/cm(2). Laser irradiations were performed using a 636-nm diode laser with an output power of 110 mW at 4.98 J/cm(2). Changes in cellular responses were evaluated by cell morphology, viability, proliferation, and cytotoxicity. While control groups 1, 2, and 3 showed no changes in cell morphology, viability, proliferation, or cytotoxicity, group 4 receiving both photosensitizer and irradiation showed changes in cell morphology, a decrease in cell viability and proliferation, and an increase in cytotoxicity, cell death, and cell membrane damage. Irradiation or photosensitizer alone had no effect on the lung cancer cells since the cells remained viable and showed no evidence of damage. However, irradiation in the presence of a photosensitizer induced cell death. PMID:21279402

Manoto, Sello Lebohang; Abrahamse, Heidi

2011-07-01

277

PDMP induces rapid changes in vacuole morphology in Arabidopsis root cells  

PubMed Central

PDMP (d-l-threo-1-phenyl-2-decanoyl amino-3-morpholino-1-propanol) is a well-known inhibitor of glucosylceramide synthase (GCS), a key enzyme in sphingolipid biosynthesis. Through the resultant increase in ceramides which interact with mTOR and Beclin1 (Atg6), this drug is also known to induce macroautophagy in mammalian cells. This study investigated the response of Arabidopsis root cells to PDMP, and what are probably numerous tightly packed small vacuoles in the control cells appear to fuse to form a single globular-shaped vacuole. However, during this fusion process, cytoplasm channels between the individual vacuoles become trapped in deep invaginations of the tonoplast. In both optical sections in the confocal laser scanning microscope and in ultrathin sections in the electron microscope, these invaginations have the appearance of cytoplasmic inclusions in the vacuole lumen. These changes in vacuole morphology are rapid (occurring within minutes after application of PDMP) and are independent of ongoing protein synthesis. The tonoplast invaginations remain visible for hours, but after 24h almost all disappear. Experiments designed to examine whether ceramide levels might be the cause of the PDMP effect have not proved conclusive. On the other hand, this study has been able to rule out the release of Ca2+ ions from intracellular stores as a contributing factor.

Kruger, Falco; Krebs, Melanie; Robinson, David G.

2013-01-01

278

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.

2014-01-01

279

Thermal instability of DLC film surface morphology - an AFM study  

NASA Astrophysics Data System (ADS)

The surface morphology of the DLC film during thermal annealing at particular temperature above the graphitization temperature shows blistering and buckling and also delaminates from the substrate. The DLC film shows poor thermal stability at higher temperature.

Maheswaran, R.; Thiruvadigal, D. John; Gopalakrishnan, C.

2012-06-01

280

Distinguishing morphological and electrical defects in polycrystalline silicon solar cells using scanning electron acoustic microscopy and electron beam induced current  

Microsoft Academic Search

Morphological and electrical defects in polycrystalline silicon solar cells are distinguished by scanning electron acoustic microscopy (SEAM) and electron beam induced current (EBIC) techniques, respectively. It was found that while some defects are both morphologically and electrically detectable, some are predominantly only either electrical or morphological in nature. Combining both SEAM and EBIC is therefore an ideal approach as the

L. Meng; D. Nagalingam; C. S. Bhatia; J. C. H. Phang

2011-01-01

281

Bone marrow examination in neuroblastoma patients: a morphologic, immunocytochemical, and immunohistochemical study.  

PubMed

Bone marrow examination was performed at the time of diagnosis, before initiation of therapy, and during follow-up of 14 consecutive patients with neuroblastoma who were treated at the National Hospital in Oslo. A total of 30 bone marrow specimens were examined by conventional histology, by immunohistochemistry with selected monoclonal antibodies to neuroblastoma cells (UJ 13A, UJ 167.11, PI 153/3, and A2B5) applied on trephines, and by morphologic evaluation of smears in addition to immunocytochemistry of aspirated bone marrow cells. The study confirmed the value of immunohistochemistry and immunocytochemistry for the detection of bone marrow involvement in neuroblastoma. Immunohistochemistry performed on bone marrow trephines was a slightly better adjunct than immunocytochemistry on aspirated bone marrow cells. PMID:2744752

Oppedal, B R; Storm-Mathisen, I; Kemshead, J T; Brandtzaeg, P

1989-08-01

282

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.

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

2008-01-01

283

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.

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

2011-01-01

284

Morphological study on the hereditary neurogenic amyotrophic dogs: Accumulation of lipid compound-like structures in the lower motor neuron  

Microsoft Academic Search

A morphological study was performed on hereditary neurogenic amyotrophic dogs, the clinical features of which especially resembled spinal progressive muscular atrophy (SPMA), a human motor neuron disease. The skeletal muscles showed obvious neurogenic atrophy with endomysial fibrosis. The peripheral nerves revealed axonal degeneration mainly limited to the motor nerve. In the spinal cord, the number of anterior horn cells seemed

S. Izumo; F. Ikuta; A. Igata; M. Osame; C. Yamauchi; S. Inada

1983-01-01

285

A morphological study on the classification of maxillary dental arches.  

PubMed

To evaluate the morphology of dental arches, 62 (male: 36, female: 26) paired casts having normal dentitions and occlusion were selected from 396 (age: 18 to 26 years old; male: 257, female: 139) sets of dental study models. The maxillary dentitions were preliminarily classified as square, round-square, round and round V-shaped arches based on the conventional morphological descriptions. Midpoints of the incisor edge (I1(R), I1(L), I2(R), & I2(L), summits of the cuspids (CR & CL), buccal cusps of the premolars (P1(R), P1(L), P2(R), & P2L), mesial buccal cusps of the first and second molars (M1(R), M1(L), M2(R), & M2(L)), and the midpoint (A) of line I1(R)-I1(L) were designated as reference points. From A, let a vertical line intersected line M2(R)-M2(L) at reference point B. The line A-B intersected C(R)-C(L) at reference point E. We evaluated 1) the protrusion of the cuspids by (1) angle I2(R)-C(R)-P1(R) (angle R) + angle I2(L)-C(L)-P1(L) (angle L); 2) the curvature of the anterior teeth by (2) A-B/C(R)-C(L), (3) 180 degrees - angle C(R)-A-C(L), and (4) A-E/C(R)-C(L); 3) the length to width ratio of the dental arch by (5) A-B/M2(R)-M2(L); 4) the degree of roundness of the maxillary arch by estimation of (6) (rtheta5 - rtheta4)R + (rtheta5 - rtheta4)L; and 5) an item (7) for the differentiation of type I and type II round-square arches by relating the bilateral contour and position of break line P1-P2-M1-M2 (i) to line P1-M2 (ii). The data of items (1), (2), (3), (4), (5), and (6) were further standardized and summarized into three essential principal components: 1) the curvature of the anterior teeth, 2) the curvilinear contour of the dental arch, and 3) the length-to-width ratio of the dental arch. The results indicated that: 1) 60% of the maxillary dentitions were round-square arches which showed no prominent principal component; 2) square maxillary arches distinctly showed a small (1) angle R + angle L; 3) round arches were characteristic by small (6) (rtheta5 - rtheta4)R + (rtheta5 - rtheta4)L values; and 4) round V-shaped arches had large (1), (3) and (4) values. PMID:15248560

Nakatsuka, Michiko; Iwai, Yasutomo; Jue, Seong-Suk; Oh, Sang-Hoon; Guo, Lian; Tominaga, Yasuhiko; Kumabe, Shunji

2004-05-01

286

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

PubMed Central

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

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

2013-01-01

287

Porcine dendritic cells generated in vitro: morphological, phenotypic and functional properties  

PubMed Central

Despite the central role that dendritic cells (DC) play in immune regulation and antigen presentation, little is known about porcine DC. In this study, two sources of DC were employed. Bone marrow haematopoietic cell-derived DC (BM-DC) were generated using granulocyte–macrophage colony-stimulating factor (GM-CSF) in the presence or absence of tumour necrosis factor-? (TNF-?). Monocyte-derived DC (M?-DC) were generated with GM-CSF and interleukin-4 (IL-4). In both systems, non-adherent cells developed with dendritic morphology, expressing high levels of major histocompatibility complex (MHC) class II. The presence of TNF-? increased the BM-DC yield, and enhanced T-cell stimulatory capacity. Both BM-DC and M?-DC expressed the pan-myeloid marker SWC3, as well as CD1 and CD80/86, but were also CD14+ and CD16+. The CD16 molecule was functional, acting as a low-affinity Fc receptor. In contrast, the CD14 on DC appeared to differ functionally from monocyte CD14: attempts to block CD14, in terms of lipopolysaccharide (LPS)-induced procoagulant activity (PCA), failed. The use of TNF-? or LPS for DC maturation induced up-regulation of MHC class II and/or CD80/86, but also CD14. Allogeneic mixed leucocyte reactions and staphylococcal enterotoxin B antigen presentation assays demonstrated that these DC possessed potent T-cell stimulatory capacity. No T helper cell polarization was noted. Both the BM-DC and the M?-DC induced a strong interferon-? and IL-4 response. Taken together, porcine DC generated in vitro possess certain characteristics relating them to DC from other species including humans, but the continued presence of CD14 and CD16 on mature and immature porcine DC was a notable difference.

Carrasco, Carlos P; Rigden, Rachael C; Schaffner, Rene; Gerber, Heidi; Neuhaus, Viviane; Inumaru, Shigeki; Takamatsu, Haru; Bertoni, Guiseppe; McCullough, Kenneth C; Summerfield, Artur

2001-01-01

288

[Incidence, morphology and diagnostic studies of Entamoeba gingivalis, Gros, 1849].  

PubMed

Entamoeba gingivalis is found only in its trophozoite form and it is postulated that its main transmission mechanism is through the kiss. E. gingivalis is considered pathogenic by some authors and commensal to others. It does not have a defined role in the installation of disease. To address some of this questions we studied a 100 patients who were seen through the Odontological Hospital from the Universidade Federal de Uberlândia in order to determine its frequency in the buccal cavity. The material were collected using swabs from four different buccal sites and the smears were stained by a modified Papanicolaou technique. The results revealed positivity index of 62%. The affinity of the dye to the food vacuole contents and to the ingested bacterias prevents clear visualisation of the central and peripherical chromatin constituents of the parasite's nucleus. Mouth washes with 3ml of saline from 10 patients, were used to evaluate which parasitological method of diagnosis (fresh, iron-haematoxylin stained, Giemsa and Papanicolaou) gives better visualisation of the parasite. The mouth washes sediment from fresh material revealed 100% of positivity and clear visualisation of the free form and locomotion of the trophozoites. No stained technique of the smear showed adequate visualisation, presenting the nucleus partially covered by the food vacuoles. In stained preparations by toluidine blue ultrastructure analysis of the morphology of parasite can be observed. PMID:8668839

Favoreto Junior, S; Machado, M I

1995-01-01

289

Perinatal hemochromatosis. Clinical, morphologic, and quantitative iron studies.  

PubMed Central

Three sibling and two isolated-case perinates (4 newborn, 1 stillborn) died with siderotic cirrhosis and widespread parenchymal siderosis, the latter similar to that seen in both hereditary and secondary hemochromatosis. Reticuloendothelial siderosis was absent, as occurs in primary hemochromatosis. Studies of iron metabolism were performed antemortem in two of the siblings and ante-, post- and internatally in their mother, who showed hyperferremia antenatally. The only finding in the affected family suggestive of hereditary hemochromatosis was the commonly associated HLA haplotype (A3, B7) in the mother and an infant. Liver morphology, including immunocytochemistry and ultrastructure, was similar in the 5 infants and suggested that liver disease commenced as massive necrosis in midfetal life. Histologic grading and chemical assays for iron and copper on liver and spleen of the 5 index cases were compared with 26 controls; placentas were compared with 12 control placentas. Hepatic iron concentration, but not hepatic copper concentration, was significantly increased in index cases, compared with controls. Hepatic iron to copper ratio was significantly increased in index cases, compared with controls, but this ratio was unaltered in spleen and placenta. Total hepatic iron, but not total hepatic copper, was significantly increased in index cases, compared with a subgroup of 11 controls of low gestational age, similar to the fetal stage when liver disease commenced in utero. The results suggest that, irrespective of the fetal liver disease being genetic or acquired, hepatic iron overload was directly involved in pathogenesis. Images Figure 5 Figure 1 Figure 2 Figure 3 Figure 4

Silver, M. M.; Beverley, D. W.; Valberg, L. S.; Cutz, E.; Phillips, M. J.; Shaheed, W. A.

1987-01-01

290

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

291

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.

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

2014-01-01

292

Fibrillarin, a nucleolar protein, is required for normal nuclear morphology and cellular growth in HeLa cells  

SciTech Connect

Fibrillarin is a key small nucleolar protein in eukaryotes, which has an important role in pre-rRNA processing during ribosomal biogenesis. Though several functions of fibrillarin are known, its function during the cell cycle is still unknown. In this study, we confirmed the dynamic localization of fibrillarin during the cell cycle of HeLa cells and also performed functional studies by using a combination of immunofluorescence microscopy and RNAi technique. We observed that depletion of fibrillarin has almost no effect on the nucleolar structure. However, fibrillarin-depleted cells showed abnormal nuclear morphology. Moreover, fibrillarin depletion resulted in the reduction of the cellular growth and modest accumulation of cells with 4n DNA content. Our data suggest that fibrillarin would play a critical role in the maintenance of nuclear shape and cellular growth.

Amin, Mohammed Abdullahel [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Matsunaga, Sachihiro [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Ma, Nan [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Takata, Hideaki [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Yokoyama, Masami [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Uchiyama, Susumu [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan); Fukui, Kiichi [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka (Japan)]. E-mail: kfukui@bio.eng.osaka-u.ac.jp

2007-08-24

293

Morphological comparison and functional reconstitution of rat hepatic parenchymal cells on various matrices.  

PubMed

Four types of materials, type I collagen coat (Coat), acid-soluble type I collagen gel (Hardgel), pepsin-treated acid-soluble type I collagen gel (Softgel), and an extract of extracellular matrix of the murine Engelbreth-Holm-Swarm sarcoma (Matrigel), were used as matrices to culture rat hepatic parenchymal cells, and their morphological changes and adhesion were compared to the matrices by electron microscopic observations. Hepatic parenchymal cells cultured on Coat and Hardgel were extended and flattened, whereas cells cultured on Softgel and Matrigel assembled and formed aggregates. Such aggregates consisted of several hepatic parenchymal cells, with a recognizable bile duct-like alveolus on the inside. Morphologically, the aggregates were more spherical on Matrigel and oval shaped on Softgel. Microvilli of the cell surface were parallel to the matrix on Matrigel, but invaded into the gel on Softgel. Subsequently, investigation into how these morphological features affected the liver-specific functions, including secretion of albumin and induction of P450 by 3-methylcholanthrene, demonstrated that a high level of liver function was maintained in a long-term culture in hepatic parenchymal cells on Softgel. These results suggest that hepatic parenchymal cell interactions were stronger with Softgel than with Matrigel, and that Softgel appears to closely mimic the in vivo environment. PMID:9792035

Awata, R; Sawai, H; Imai, K; Terada, K; Senoo, H; Sugiyama, T

1998-09-01

294

A morphological study of the left bundle branch in the normal human heart.  

PubMed

To clarify the distribution pattern of the left bundle branch (LBB) in the human heart, the AV conduction system was studied in 13 autopsied hearts obtained from subjects aged 50 to 80 years. Vertical serial sections (7 micron) of the bundle of His and LBB were prepared and every 20th section was stained alternately with hematoxylin-eosin (HE) or by the elastica van Gieson (EVG) method and examined by light microscopy. Reconstruction was performed using a two-dimensional system in order to histologically differentiate the bundle cells from Purkinje cells. The LBB bifurcated into the anterior and posterior radiations and the cells in the septal portion were almost all Purkinje cells except in two cases showing a septal branch between the two radiations. The LBB usually branched widely from the bundle of His. An extremely anterior fascicle of the LBB was found in all cases. The distribution of the LBB at the top of the ventricular septum was divided into network and continuous types. Purkinje cells were present on both the atrial and apical sides of the two main radiations. It was suggested that these findings resulted from the fact that we morphologically differentiated the bundle cells from Purkinje cells by light microscopy. PMID:3400466

Sakaguchi, Y; Konishi, N; Enoki, N; Shimoyama, T; Hiasa, Y; Murata, Y; Kagoshima, T; Ishikawa, H; Okada, R

1988-04-01

295

Differences in Virus-Induced Cell Morphology and in Virus Maturation between MVA and Other Strains (WR, Ankara, and NYCBH) of Vaccinia Virus in Infected Human Cells  

PubMed Central

Live recombinants based on attenuated modified vaccinia virus Ankara (MVA) are potential vaccine candidates against a broad spectrum of diseases and tumors. To better understand the efficacy of MVA as a human vaccine, we analyzed by confocal and electron microscopy approaches MVA-induced morphological changes and morphogenetic stages during infection of human HeLa cells in comparison to other strains of vaccinia virus (VV): the wild-type Western Reserve (WR), Ankara, and the New York City Board of Health (NYCBH) strains. Confocal microscopy studies revealed that MVA infection alters the cytoskeleton producing elongated cells (bipolar), which do not form the characteristic actin tails. Few virions are detected in the projections connecting neighboring cells. In contrast, cells infected with the WR, Ankara, and NYCBH strains exhibit a stellated (multipolar) or rounded morphology with actin tails. A detailed transmission electron microscopy analysis of HeLa cells infected with MVA showed important differences in fine ultrastructure and amounts of the viral intermediates compared to cells infected with the other VV strains. In HeLa cells infected with MVA, the most abundant viral forms are intracellular immature virus, with few intermediates reaching the intracellular mature virus (IMV) form, at various stages of maturation, which exhibit a more rounded shape than IMVs from cells infected with the other VV strains. The “IMVs” from MVA-infected cells have an abnormal internal structure (“atypical” viruses) with potential alterations in the core-envelope interactions and are unable to significantly acquire the additional double envelope to render intracellular envelope virus. The presence of potential cell-associated envelope virus is very scarce. Our findings revealed that MVA in human cells promotes characteristic morphological changes to the cells and is able to reach the IMV stage, but these virions were not structurally normal and the subsequent steps in the morphogenetic pathway are blocked.

Gallego-Gomez, Juan Carlos; Risco, Cristina; Rodriguez, Dolores; Cabezas, Pilar; Guerra, Susana; Carrascosa, Jose L.; Esteban, Mariano

2003-01-01

296

In Vitro Reparative Dentin: a Biochemical and Morphological Study  

PubMed Central

In this study, starting from human dental pulp cells cultured in vitro, we simulated reparative dentinogenesis using a medium supplemented with different odontogenic inductors. The differentiation of dental pulp cells in odontoblast-like cells was evaluated by means of staining, and ultramorphological, biochemical and biomolecular methods. Alizarin red staining showed mineral deposition while transmission electron microscopy revealed a synthesis of extracellular matrix fibers during the differentiation process. Biochemical assays demonstrated that the differentiated phenotype expressed odontoblast markers, such as Dentin Matrix Protein 1 (DMP1) and Dentin Sialoprotein (DSP), as well as type I collagen. Quantitative data regarding the mRNA expression of DMP1, DSP and type I collagen were obtained by Real Time PCR. Immunofluorescence data demonstrated the various localizations of DSP and DMP1 during odontoblast differentiation. Based on our results, we obtained odontoblast-like cells which simulated the reparative dentin processes in order to better investigate the mechanism of odontoblast differentiation, and dentin extracellular matrix deposition and mineralization.

Teti, G.; Salvatore, V.; Ruggeri, A.; Manzoli, L.; Gesi, M.; Orsini, G.; Falconi, M.

2013-01-01

297

Differential effects of intrastriatal 6-hydroxydopamine on cell number and morphology in midbrain dopaminergic subregions of the rat.  

PubMed

The midbrain dopaminergic perikarya are differentially affected in Parkinson?s disease (PD). This study compared the effects of a partial unilateral intrastriatal 6-hydroxydopamine (6-OHDA) lesion model of PD on the number, morphology, and nucleolar volume of dopaminergic cells in the substantia nigra pars compacta (SNpc), ventral tegmental area (VTA), and retrorubral field (RRF). Adult, male rats (n=10) underwent unilateral intrastriatal infusion of 6-OHDA (12.5?g). Lesions were verified by amphetamine-stimulated rotation 7 days post-infusion. Rats were euthanized 14 days after treatment with 6-OHDA and brains were stained with a tyrosine hydroxylase-silver nucleolar (TH-AgNOR) stain. Dopaminergic cell number and morphology in the lesioned and intact hemispheres were quantified using stereological methods. The magnitude of decrease in planimetric volume, neuronal number, cell density, and neuronal volume resulting from 6-OHDA lesion differed between regions, with the SNpc exhibiting the greatest loss of neurons (46%), but the smallest decrease in neuronal volume (13%). The lesion also resulted in a decrease in nucleolar volume that was similar in all three regions (22-26%). These findings indicate that intrastriatal 6-OHDA lesion differentially affects dopaminergic neurons in the SNpc, VTA, and RRF; however, the resulting changes in nucleolar morphology suggest a similar cellular response to the toxin in all three cell populations. PMID:24924804

Healy-Stoffel, Michelle; Omar Ahmad, S; Stanford, John A; Levant, Beth

2014-07-29

298

High-grade urothelial carcinoma of the renal pelvis: clinicopathologic study of 108 cases with emphasis on unusual morphologic variants  

Microsoft Academic Search

A clinicopathologic study of 108 cases of high-grade urothelial carcinomas of the renal pelvis is presented. Of the 108 tumors, 44 (40%) showed unusual morphologic features, including micropapillary areas (four cases), lymphoepithelioma-like carcinoma (two cases), sarcomatoid carcinoma (eight cases, including pseudoangiosarcomatous type), squamous differentiation and squamous cell carcinoma (15 cases), clear cells (two cases), glandular differentiation (two cases), rhabdoid, signet-ring

Delia Perez-Montiel; Paul E Wakely; Ondrej Hes; Michal Michal; Saul Suster

2006-01-01

299

Characterization of interfacial morphology in polymer electrolyte fuel cells: Microporous layer and catalyst layer surfaces  

Microsoft Academic Search

The interface between the micro-porous layer (MPL) and the catalyst layer (CL) can have an impact on thermal, electrical and two-phase mass transport in a polymer electrolyte fuel cell (PEFC). However, there is scant information available regarding the true morphology of the MPL and CL surfaces. In this work, optical profilometry is used to characterize the MPL and CL surfaces

F. E. Hizir; S. O. Ural; E. C. Kumbur; M. M. Mench

2010-01-01

300

Classification of cervical cell nuclei using morphological segmentation and textural feature extraction  

Microsoft Academic Search

This paper presents preliminary results for the classification of Pap Smear cell nuclei, using gray level co-occurrence matrix (GLCM) textural features. We outline a method of nuclear segmentation using fast morphological gray-scale transforms. For each segmented nucleus, features derived from a modified form of the GLCM are extracted over several angle and distance measures. Linear discriminant analysis is performed on

Ross F. Walker; Paul Jackway; Brian Lovell; I. D. Longstaff

1994-01-01

301

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

302

Objective assessment of changes in nuclear morphology and cell distribution following induction of apoptosis  

PubMed Central

Background To objectively measure changes in nuclear morphology and cell distribution following induction of apoptosis. Methods A spontaneously immortalized retinal pigment epithelial cell line (ARPE-19) was cultured for three days in DMEM/F12 with 10% fetal bovine serum followed by 24?hours incubation in staurosporine to induce apoptosis. Cells that were not incubated in staurosporine served as control. Caspase-3 expression in apoptotic cells was demonstrated by quantitative immunofluorescence. Nuclei were counterstained with DAPI. Assessments of nuclear morphology and cell distribution were performed using ImageJ software. Statistical analyses included Student’s t-test and Pearson’s correlation coefficient. Nearest neighbor analysis was used to assess cell nuclei distribution. Results Caspase-3 expression in staurosporine-incubated cells increased by 471%?±?182% compared to control (P?=?0.014). Relative to the control, cells in the staurosporine-incubated cultures had smaller average nuclear area (68%?±?5%; P?Cell nuclei from the staurosporine-group (R?=?1.12?±?0.04; P?cell distribution. However, the staurosporine-incubated group had a significantly lower R-value compared to the control (P?=?0.002), which indicated a move towards cell clustering following induction of apoptosis. Caspase-3 expression of each individual cell correlated significantly with the following morphological indicators: circumference of the nucleus divided by form factor (r?=?-0.475; P?cells demonstrate morphological features that can be objectively quantified using freely available ImageJ software. A novel morphological indicator, defined as the nuclear circumference divided by form factor, demonstrated the strongest correlation with caspase-3 expression. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/3271993311662947

2014-01-01

303

Cell morphology variations of Klebsiella pneumoniae induced by acetate stress using biomimetic vesicle assay.  

PubMed

Supplementation with acetate under low levels was used as a novel approach to control the morphological development of Klebsiella pneumoniae aimed to improve 1,3-propanediol (1,3-PD) production. A full range of morphological types formed from rod shape to oval shape even round shape in response to different concentrations of acetate. The cell growth and 1,3-PD productions in the shake flasks with 0.5 g/L acetate addition were improved by 9.4 and 28.37%, respectively, as compared to the control, while the cell became shorter and began to lose its original shape. The cell membrane penetration by acetate was investigated by the biomimetic vesicles, while higher concentration of acetate led to more moderate colorimetric transitions. Moreover, the percentage composition of unsaturated fatty acid (UFA) was increased as well as the increased concentrations of acetate, whereas higher UFA percentage, higher fluidity of bacterial cell membrane. PMID:23892619

Lu, Shengguo; Han, Yuwang; Duan, Xujia; Luo, Fang; Zhu, Lingyan; Li, Shuang; Huang, He

2013-10-01

304

N-Nitrosodiethylamine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone Induced Morphological Transformation of C3H/10T1/2CL8 Cells Expressing Human Cytochrome P450 2A6.  

National Technical Information Service (NTIS)

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. A human cytochrome P450 isozyme, CYP2A6, has been successfu...

S. Nesnow S. Beck S. Rosenblum J. Lasley H. F. Tiano M. Hosokawa C. L. Crespi R. Langenbach

1994-01-01

305

1, 25(OH)2 Vitamin D3 Inhibits Cell Proliferation by Promoting Cell Cycle Arrest Without Inducing Apoptosis and Modifies Cell Morphology of Mesenchymal Multipotent Cells  

PubMed Central

The vitamin D receptor (VDR) and its ligand 1,25D, play an important role in regulating cell growth and cell fate. We examined the effect of 1,25D on cell morphology, cell proliferation, cell cycle progression and apoptosis on mesenchymal multipotent cells. Multipotent cells were treated with and without 1,25D in a time and dose dependent manner. Changes in cell morphology were evaluated by a green fluorescence fluorocrome. Cell proliferation was determined by the Formazan assay and PCNA antigen expression. The expression of genes related to the cell cycle was analyzed by DNA microarrays, RT2PCR arrays and western blots. Apoptosis was evaluated by TUNEL assay, and the expression of pro and anti-apoptotic related genes by RT2PCR arrays and western blots. 1,25D inhibited cell proliferation, induced cell cycle arrest, and promoted accumulation of cells in G0/G1 phase without inducing apoptosis. An increase in cell size was associated with a decrease in the GTPase Rho and the atypical Rho family GTPase Rhou/Wrch-1 expression without inducing Wnt-1 expression. Survivin expression was also increased and may represent a novel 1,25D mediated pathway regulating tissue injury and fibrosis. The data provide a mechanistic explanation for the anti-proliferative and anti-apoptototic properties of 1,25D in mesenchymal multipotent cells.

Artaza, Jorge N.; Sirad, Fara; Ferrini, Monica G; Norris, Keith C.

2010-01-01

306

Rim morphology of nanopore for studying single biomolecule  

NASA Astrophysics Data System (ADS)

The fabrication and application of micro- and nanoscale containers and devices are recently attracted much attention. The top profiles of these nanoscale patterns are very important for nano-devices integration. The morphologies of small containers, nanopit and nanopore fabricated with focused ion beam (FIB) milling tool, are explored by atomic force microscopy (AFM). The topography of every pattern looks like a volcano. The protruded ring-shaped structures surrounding the crater are attributed to the swelling due to the amorphization when FIB processed the crystal silicon nitride (Si3N4) substrate. In addition, the morphologies of anodic alumina oxide (AAO) membranes fabricated by anodizing of metallic aluminum are discussed.

Wang, Kaige; Li, Qiang; Xu, Guiwen; Jin, Aizi; Gu, Changzhi

2009-05-01

307

Horizontal cell morphology in nocturnal and diurnal primates: a comparison between owl-monkey (Aotus) and capuchin monkey (Cebus).  

PubMed

Horizontal cell morphology was studied in the retina of the nocturnal owl-monkey, Aotus, and compared with that of its diurnal, close relative, the capuchin monkey, Cebus . Cells were initially labeled with DiI and the staining was later photoconverted in a stable precipitated using DAB as chromogen. The sizes of cell bodies, dendritic fields, and axon terminals, number of dendritic clusters, intercluster spacing, and intercone spacing were measured at increasing eccentricities. Two distinct morphological classes of horizontal cells were identified, which resembled those of H1 and H3 cells described in diurnal monkeys. A few examples of a third class, possibly corresponding to the H2 cells of diurnal monkeys, were labeled. Both H1 and H3 cells increased in size and had increasing numbers of dendritic clusters with eccentricity. H3 cells were larger and had a larger number of dendritic clusters than H1 cells. Owl-monkey H1 cells had larger dendritic fields than capuchin monkey H1 cells at all quadrants in the central and midperipheral retinal regions, but the difference disappeared in the far periphery. Owl-monkey and capuchin monkey H1 cells had about the same number of dendritic clusters across eccentricity. As owl-monkey H1 cells were larger than capuchin monkey H1 cells, the equal number of clusters in these two primates was due to the fact that they were more spaced in the owl-monkey cells. H1 intercluster distance closely matched intercone spacing for both the owl-monkey and capuchin monkey retinas. On the other hand, H3 intercluster distance was larger than intercone spacing in the retina of both primates. Owl-monkey H1 axon terminals had 2-3 times more knobs than capuchin monkey H1 axon terminals in spite of having about the same size and, consequently, knob density was 2-3 times higher for owl-monkey than capuchin monkey H1 axon terminals across all eccentricities. The differences observed between owl-monkey and capuchin monkey horizontal cells, regarding the morphology of their dendritic trees and axon terminals, may be related to the differences found in the cone-to-rod ratio in the retina of these two primates. They seem to represent retinal specializations to the nocturnal and diurnal life styles of the owl-monkey and capuchin monkey, respectively. PMID:16212699

Dos Santos, Setsuko N; Dos Reis, José Wesley L; Da Silva Filho, Manoel; Kremers, Jan; Silveira, Luiz Carlos L

2005-01-01

308

Aggressive Variant of Morphologically Typical T Large Granular Lymphocyte Leukemia\\/Lymphoma Lacking NK Cell Markers  

Microsoft Academic Search

A 46-year-old woman with a previous diagnosis of sarcoidosis presented with morphologically typical large granular lymphocyte (LGL) leukemia\\/lymphoma with an aggressive clinical course. Epstein-Barr virus DNA was detected in peripheral blood mononuclear cells by PCR. The phenotype was typical of the T cell lineage (CD2+ CD3+ CD5+ CD7+ CD8+ TCR??+) but with the absence of the CD16, CD56, CD57 NK

Roberto Passetto Falcão; Belinda Pinto Simões; Aglair B. Garcia; Benedito A. F. Fonseca; João Terra Filho

2000-01-01

309

Characterization of lactate dehydrogenase isozyme pattern and morphology of three marine fish cell lines  

Microsoft Academic Search

Three continuous marine fish cell lines of FG (i.e., Flounder Gill) from flounder (Paralichthys olivaceus) gill, SPH (i.e., Sea Perch Heart) from sea perch (Lateolabrax japonicus) heart and RSBF (i.e., Red Sea Bream Fin) from red sea bream (Pagrosomus major) fin, were characterized by lactate dehydrogenase (LDH) isozyme and morphological analysis. The LDH isozyme patterns of these\\u000a three cell lines

Hua-Rong Guo; Shi-Cui Zhang; Hong-Yan Li; Shang-Liang Tong; Jian-Hai Xiang

2002-01-01

310

Aggressive course of primary plasma cell leukemia with unusual morphological and cytogenetic features  

Microsoft Academic Search

A case of aggressive plasma cell leukemia with unusual morphological and cytogenetic features is reported. A 65-year-old man was admitted to hospital due to anemia, thrombocytopenia, and renal insufficiency. Bone marrow examination and peripheral blood smear revealed a large number of pleomorphic cells with convoluted and multilobulated nuclei. Immunohistochemistry of the bone marrow biopsy was negative for anti-keratin antibodies CAM.5.2

J. Richter; A. Swedin; T. Olofsson; B. Johansson; M. Åkerman; I. Winqvist

1995-01-01

311

Unsupervised modeling of cell morphology dynamics for time-lapse microscopy.  

PubMed

Analysis of cellular phenotypes in large imaging data sets conventionally involves supervised statistical methods, which require user-annotated training data. This paper introduces an unsupervised learning method, based on temporally constrained combinatorial clustering, for automatic prediction of cell morphology classes in time-resolved images. We applied the unsupervised method to diverse fluorescent markers and screening data and validated accurate classification of human cell phenotypes, demonstrating fully objective data labeling in image-based systems biology. PMID:22635062

Zhong, Qing; Busetto, Alberto Giovanni; Fededa, Juan P; Buhmann, Joachim M; Gerlich, Daniel W

2012-07-01

312

Effect of electrical properties, transmittance, and morphology of ITO electrode on polymer solar cells characteristics  

NASA Astrophysics Data System (ADS)

We investigated the influence of ITO properties on the performance of bulk heterojunction solar cells. The morphology, electrical and optical properties of ITO electrodes were characterized. The power conversion efficiency of cells made on different ITO substrates varied significantly from 2.3% to 3.1%. It was found that for a higher sheet resistance ITO substrate, the sheet resistance was the dominant parameter affecting the performance of the based solar cells, while for the lower ( below 20 ohm/square) sheet resistance, transmittance in the region where polymer strongly absorbs and the surface roughness of the substrate had significant effect on the solar cells performance.

Liu, Xiang; Ng, Annie; Ng, Yip Hang; Djuriši?, Aleksandra B.; Ng, Alan Man Ching; Chan, Wai Kin

2013-03-01

313

Intelligent Computation and Precise Measurement of DNA Content in Cell Nucleus: A Calibration Approach Based on Morphology and Support Vector Regression  

Microsoft Academic Search

In the study of quantitative cytology, the measurement of the DNA content in cell nuclear is the most important basis and necessary premise of cancer screening and diagnosis. Due to some unavoidable factors, certain errors may occur in the measurement of the DNA content through processing and analysis of the cell nuclei image. A new calibration approach based on morphology

Gang Lu; Yi Zhang; Baochuan Pang

2009-01-01

314

Optimization of Cell Morphology Measurement via Single-Molecule Tracking PALM  

PubMed Central

In neurons, the shape of dendritic spines relates to synapse function, which is rapidly altered during experience-dependent neural plasticity. The small size of spines makes detailed measurement of their morphology in living cells best suited to super-resolution imaging techniques. The distribution of molecular positions mapped via live-cell Photoactivated Localization Microscopy (PALM) is a powerful approach, but molecular motion complicates this analysis and can degrade overall resolution of the morphological reconstruction. Nevertheless, the motion is of additional interest because tracking single molecules provides diffusion coefficients, bound fraction, and other key functional parameters. We used Monte Carlo simulations to examine features of single-molecule tracking of practical utility for the simultaneous determination of cell morphology. We find that the accuracy of determining both distance and angle of motion depend heavily on the precision with which molecules are localized. Strikingly, diffusion within a bounded region resulted in an inward bias of localizations away from the edges, inaccurately reflecting the region structure. This inward bias additionally resulted in a counterintuitive reduction of measured diffusion coefficient for fast-moving molecules; this effect was accentuated by the long camera exposures typically used in single-molecule tracking. Thus, accurate determination of cell morphology from rapidly moving molecules requires the use of short integration times within each image to minimize artifacts caused by motion during image acquisition. Sequential imaging of neuronal processes using excitation pulses of either 2 ms or 10 ms within imaging frames confirmed this: processes appeared erroneously thinner when imaged using the longer excitation pulse. Using this pulsed excitation approach, we show that PALM can be used to image spine and spine neck morphology in living neurons. These results clarify a number of issues involved in interpretation of single-molecule data in living cells and provide a method to minimize artifacts in single-molecule experiments.

Frost, Nicholas A.; Lu, Hsiangmin E.; Blanpied, Thomas A.

2012-01-01

315

Mucocele-like tumor and columnar cell hyperplasia of the breast occurring in a morphologic continuum  

PubMed Central

Introduction Mucocele-like tumor was originally described in 1986 as a benign breast proliferation consisting of multiple dilated cysts lined by cytologically bland, flat to cuboidal cells. Subsequent reports described the coexistence of, including the morphologic inter-transitions between, mucocele-like tumor and a variety of other breast proliferations, including intraductal carcinoma, invasive carcinoma, atypical ductal hyperplasia, and hyperplasia of the usual type. The spectrum of breast alterations characterized by variably enlarged terminal-ductal lobular units lined by variably hyperplastic and variably atypical columnar cells has been the subject of significant discussion in the recent literature. In one scheme, these lesions may be classified into four groups, that is, columnar cell change with and without atypia and columnar cell hyperplasia with and without atypia. Morphologic and molecular observations suggest an association, perhaps in a nonobligate precursor role, between some columnar cell lesions and a variety of other neoplastic lesions. Case presentation We describe the case of a 43-year-old woman whose breast tumor contained areas diagnostic of mucocele-like tumor and columnar cell hyperplasia, with morphologic transitions in between. Conclusion Our case represents the second broadly similar case that has been reported, and suggests a potential relationship between these two enigmatic lesions.

Fadare, Oluwole; Mariappan, M Rajan

2008-01-01

316

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

317

Distinct roles for paxillin and Hic-5 in regulating breast cancer cell morphology, invasion, and metastasis  

PubMed Central

Individual metastatic tumor cells exhibit two interconvertible modes of cell motility during tissue invasion that are classified as either mesenchymal or amoeboid. The molecular mechanisms by which invasive breast cancer cells regulate this migratory plasticity have yet to be fully elucidated. Herein we show that the focal adhesion adaptor protein, paxillin, and the closely related Hic-5 have distinct and unique roles in the regulation of breast cancer cell lung metastasis by modulating cell morphology and cell invasion through three-dimensional extracellular matrices (3D ECMs). Cells depleted of paxillin by RNA interference displayed a highly elongated mesenchymal morphology, whereas Hic-5 knockdown induced an amoeboid phenotype with both cell populations exhibiting reduced plasticity, migration persistence, and velocity through 3D ECM environments. In evaluating associated signaling pathways, we determined that Rac1 activity was increased in cells devoid of paxillin whereas Hic-5 silencing resulted in elevated RhoA activity and associated Rho kinase–induced nonmuscle myosin II activity. Hic-5 was essential for adhesion formation in 3D ECMs, and analysis of adhesion dynamics and lifetime identified paxillin as a key regulator of 3D adhesion assembly, stabilization, and disassembly.

Deakin, Nicholas O.; Turner, Christopher E.

2011-01-01

318

Morphological analysis of nuclear separation and cell division during the life cycle of Escherichia coli.  

PubMed Central

Quantitative electron microscope observations were performed on Escherichia coli B/r after balanced growth with doubling times (tau) of 32 and 60 min. The experimental approach allowed the timing of morphological events during the cell cycle by classifying serially sectioned cells according to length. Visible separation of the nucleoplasm was found to coincide with the time of termination of chromosome replication as predicted by the Cooper-Helmstetter model. The duration of the process of constrictive cell division (10 min) appeared to be independent of the growth rate for tau equals 60 min or less but to increase with increase doubling time in more slowly growing cells. Physiological division, i.e., compartmentalization prior to physical separation of the cells, was only observed to occur in the last minute of the cell cycle. The morphological results indicate that cell elongation continues during the division process in cells with tau equals 32 min, but fails to continue in cells with tau equals 60 min. Images

Woldringh, C L

1976-01-01

319

Effects of 17\\/J-Estradiol and Progesterone on Growth and Morphology of Human Endometrial Carcinoma Cells in V\\/fro1  

Microsoft Academic Search

SUMMARY The effects of 17\\/3-estradiol and progesterone on the rate of growth and the morphological changes of human en- dometrial adenocarcinoma cells were studied in in vitro culture. 17\\/3-Estradiolenhanced their growth and produced no cellular morphological changes at low concentrations of less than 1 \\/¿g\\/ml,whereas it suppressed their growth and produced such cellular changes as enlargement of nuclei, karyorrhexis, and

Isamu Ishiwata; Shiro Nozawa; Hideo Okumura

1977-01-01

320

Morphology and connections of intratrigeminal cells and axons in the macaque monkey  

PubMed Central

Trigeminal primary afferent fibers have small receptive fields and discrete submodalities, but second order trigeminal neurons often display larger receptive fields with complex, multimodal responses. Moreover, while most large caliber afferents terminate exclusively in the principal trigeminal nucleus, and pars caudalis (sVc) of the spinal trigeminal nucleus receives almost exclusively small caliber afferents, the characteristics of second order neurons do not always reflect this dichotomy. These surprising characteristics may be due to a network of intratrigeminal connections modifying primary afferent contributions. This study characterizes the distribution and morphology of intratrigeminal cells and axons in a macaque monkeys. Tracer injections centered in the principal nucleus (pV) and adjacent pars oralis retrogradely labeled neurons bilaterally in pars interpolaris (sVi), but only ipsilaterally, in sVc. Labeled axons terminated contralaterally within sVi and caudalis. Features of the intratrigeminal cells in ipsilateral sVc suggest that both nociceptive and non-nociceptive neurons project to principalis. A commissural projection to contralateral principalis was also revealed. Injections into sVc labeled cells and terminals in pV and pars oralis on both sides, indicating the presence of bilateral reciprocal connections. Labeled terminals and cells were also present bilaterally in sVi and in contralateral sVc. Interpolaris injections produced labeling patterns similar to those of sVc. Thus, the rostral and caudal poles of the macaque trigeminal complex are richly interconnected by ipsilateral ascending and descending connections providing an anatomical substrate for complex analysis of oro-facial stimuli. Sparser reciprocal crossed intratrigeminal connections may be important for conjugate reflex movements, such as the corneal blink reflex.

Warren, Susan; May, Paul J.

2013-01-01

321

No Relationship between Embryo Morphology and Successful Derivation of Human Embryonic Stem Cell Lines  

PubMed Central

Background The large number (30) of permanent human embryonic stem cell (hESC) lines and additional 29 which did not continue growing, in our laboratory at Karolinska Institutet have given us a possibility to analyse the relationship between embryo morphology and the success of derivation of hESC lines. The derivation method has been improved during the period 2002–2009, towards fewer xeno-components. Embryo quality is important as regards the likelihood of pregnancy, but there is little information regarding likelihood of stem cell derivation. Methods We evaluated the relationship of pronuclear zygote stage, the score based on embryo morphology and developmental rate at cleavage state, and the morphology of the blastocyst at the time of donation to stem cell research, to see how they correlated to successful establishment of new hESC lines. Results Derivation of hESC lines succeeded from poor quality and good quality embryos in the same extent. In several blastocysts, no real inner cell mass (ICM) was seen, but permanent well growing hESC lines could be established. One tripronuclear (3PN) zygote, which developed to blastocyst stage, gave origin to a karyotypically normal hESC line. Conclusion Even very poor quality embryos with few cells in the ICM can give origin to hESC lines.

Strom, Susanne; Rodriguez-Wallberg, Kenny; Holm, Frida; Bergstrom, Rosita; Eklund, Linda; Stromberg, Anne-Marie; Hovatta, Outi

2010-01-01

322

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.

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

2014-01-01

323

EVALUATION OF BENZO[C]CHRYSENE DIHYDRODIOLS IN THE MORPHOLOGICAL CELL TRANSFORMATION OF MOUSE EMBRYO FIBROBLAST C3H10T1/2CL8 CELLS  

EPA Science Inventory

EVALUATION OF BENZO[c]CHRYSENE DIHYDRODIOLS IN THE MORPHOLOGICAL CELL TRANSFORMATION OF MOUSE EMBRYO FIBROBLAST C3H10T?CL8 CELLS Abstract The morphological cell transforming activities of three dihydrodiols of benzo[c]chrysene (B[c]C), trans-B[c]C-7,8-diol, trans-B[c]C-9...

324

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

325

Pancreas beta-cells morphology, liver antioxidant enzymes and liver oxidative parameters in alloxan-resistant and alloxan-susceptible Wistar rats: a viable model system for the study of concepts into reactive oxygen species.  

PubMed

The aim of this study was to investigate biochemical and antioxidant parameters in alloxan-resistant (ALR) and alloxan-susceptible (ALS) rats. Diabetes was induced in 60-day-old male Wistar rats by a single intraperitonial injection of alloxan (AL, 150 mg/kg). Ten days after induction, a group of rats showed a significant decrease in glycemia. This group was named alloxan-resistant group. Susceptible rats showed a remarkable increase in the plasma lipid content, blood glucose and HbA1. Glycogen content in the liver decreased significantly in the ALS group (2.08 +/- 0.41 mg%) compared with ALR group (4.22 +/- 0.18). Aspartate aminotransferase and alanine aminotransferase activities were quantified in the plasma. Interestingly, ALR rats showed a decrease in both activities (42.1 +/- 6.11 and 21.7 +/- 5.54 U/mL) when compared with ALS rats (59.1 +/- 6.55 and 58.1 +/- 7.28 U/mL). The TBARS index was significantly increased in the ALS liver (0.38 +/- 0.08 nm/mg protein) when compared with the ALR liver (0.18 +/- 0.04). Superoxide dismutase and catalase activities in the ALR (230 +/- 13 and 131 +/- 15 U/mg protein) liver showed a marked increase when compared with the ALS liver (148 +/- 13 and 68 +/- 5 U/mg protein). The immunohistochemical and hematoxilin-eosin analysis also revealed that pancreatic islets of ALR rats display a different morphology amongst the groups. These results suggest an increased regenerative or recovery process in the ALR rat pancreatic islets and an increased hepatic antioxidant defenses in these group of alloxan-resistant rats. PMID:19049670

Behr, Guilherme Antônio; da Silva, Evandro Gomes; Ferreira, Amâncio Romanelli; Cerski, Carlos Thadeu Schmidt; Dal-Pizzol, Felipe; Moreira, José Cláudio Fonseca

2008-12-01

326

A novel MEA/AFM platform for measurement of real-time, nanometric morphological alterations of electrically stimulated neuroblastoma cells.  

PubMed

Studies of electrically induced morphological changes in neurons have either been limited by the resolution of light microscopy or the cell fixation required for electron microscopy. Atomic force microscopy (AFM), however, mechanically maps cell topography, offering exquisite resolution of evolving processes in three dimensions. In this paper, we present a microelectrode array (MEA) based platform for the real-time detection of subtle, electrically induced variations in neuronal morphology, with AFM. This platform required the customized design and production of a silicon-based MEA, integration with a commercial AFM, and the development of biological techniques for culture of neuroblastoma (SH-SY5Y) cells onto the device. Biphasic pulse trains (1 Hz) of electric current were delivered to a microelectrode interfaced with a neuroblastoma cell, and the AFM continuously recorded a cross-sectional height profile. Proof-of-principle experiments demonstrate that electric stimulation may induce fluctuations ranging in the 100-300-nm range, 75-fold greater than the systemic resolution, but smaller than the resolution of light microscopy modalities. In addition, the real-time capabilities of AFM captured a collapse (30%-40%) of a neurite cross section, seconds after electric stimulation. Ultimately, this platform can be used to nanocharacterize cell responses to electric stimulation and other biochemical cues, for use in neuronal patterning and regeneration studies. PMID:15382743

Shenai, Mahesh B; Putchakayala, Krishna G; Hessler, Jessica A; Orr, Bradford G; Banaszak Holl, Mark M; Baker, James R

2004-06-01

327

Coupling actin flow, adhesion, and morphology in a computational cell motility model  

PubMed Central

Cell migration is a pervasive process in many biology systems and involves protrusive forces generated by actin polymerization, myosin dependent contractile forces, and force transmission between the cell and the substrate through adhesion sites. Here we develop a computational model for cell motion that uses the phase-field method to solve for the moving boundary with physical membrane properties. It includes a reaction-diffusion model for the actin-myosin machinery and discrete adhesion sites which can be in a “gripping” or “slipping” mode and integrates the adhesion dynamics with the dynamics of the actin filaments, modeled as a viscous network. To test this model, we apply it to fish keratocytes, fast moving cells that maintain their morphology, and show that we are able to reproduce recent experimental results on actin flow and stress patterns. Furthermore, we explore the phase diagram of cell motility by varying myosin II activity and adhesion strength. Our model suggests that the pattern of the actin flow inside the cell, the cell velocity, and the cell morphology are determined by the integration of actin polymerization, myosin contraction, adhesion forces, and membrane forces.

Shao, Danying; Levine, Herbert; Rappel, Wouter-Jan

2012-01-01

328

Coupling actin flow, adhesion, and morphology in a computational cell motility model.  

PubMed

Cell migration is a pervasive process in many biology systems and involves protrusive forces generated by actin polymerization, myosin dependent contractile forces, and force transmission between the cell and the substrate through adhesion sites. Here we develop a computational model for cell motion that uses the phase-field method to solve for the moving boundary with physical membrane properties. It includes a reaction-diffusion model for the actin-myosin machinery and discrete adhesion sites which can be in a "gripping" or "slipping" mode and integrates the adhesion dynamics with the dynamics of the actin filaments, modeled as a viscous network. To test this model, we apply it to fish keratocytes, fast moving cells that maintain their morphology, and show that we are able to reproduce recent experimental results on actin flow and stress patterns. Furthermore, we explore the phase diagram of cell motility by varying myosin II activity and adhesion strength. Our model suggests that the pattern of the actin flow inside the cell, the cell velocity, and the cell morphology are determined by the integration of actin polymerization, myosin contraction, adhesion forces, and membrane forces. PMID:22493219

Shao, Danying; Levine, Herbert; Rappel, Wouter-Jan

2012-05-01

329

Repressed synthesis of ribosomal proteins generates protein-specific cell cycle and morphological phenotypes  

PubMed Central

The biogenesis of ribosomes is coordinated with cell growth and proliferation. Distortion of the coordinated synthesis of ribosomal components affects not only ribosome formation, but also cell fate. However, the connection between ribosome biogenesis and cell fate is not well understood. To establish a model system for inquiries into these processes, we systematically analyzed cell cycle progression, cell morphology, and bud site selection after repression of 54 individual ribosomal protein (r-protein) genes in Saccharomyces cerevisiae. We found that repression of nine 60S r-protein genes results in arrest in the G2/M phase, whereas repression of nine other 60S and 22 40S r-protein genes causes arrest in the G1 phase. Furthermore, bud morphology changes after repression of some r-protein genes. For example, very elongated buds form after repression of seven 60S r-protein genes. These genes overlap with, but are not identical to, those causing the G2/M cell cycle phenotype. Finally, repression of most r-protein genes results in changed sites of bud formation. Strikingly, the r-proteins whose repression generates similar effects on cell cycle progression cluster in the ribosome physical structure, suggesting that different topological areas of the precursor and/or mature ribosome are mechanistically connected to separate aspects of the cell cycle.

Thapa, Mamata; Bommakanti, Ananth; Shamsuzzaman, Md.; Gregory, Brian; Samsel, Leigh; Zengel, Janice M.; Lindahl, Lasse

2013-01-01

330

Ultrastructural and cytobiological studies on possible interactions between PTHrP-secreting tumor cells, stromal cells, and bone cells  

Microsoft Academic Search

Parathyroid hormone-related peptide (PTHrP) induces pathological bone resorption in an endocrine manner, resulting in hypercalcemia of malignancy. However, the histopathological aspect of the action of PTHrP secreted by tumor cells on bone resorption has not well been documented. Therefore, we studied cell–cell interactions between bone cells, stromal cells, and PTHrP-secreting tumor cells (EC-GI-10) morphologically. Tumor cells injected subcutaneously into the

Masahiro Ito; Norio Amizuka; Shohei Tanaka; Yukiko Funatsu-Ozawa; Shin-ichi Kenmotsu; Kimimitsu Oda; Tamio Nakajima; Hidehiro Ozawa

2003-01-01

331

Lipophilic organic pollutants induce changes in phospholipid and membrane protein composition leading to Vero cell morphological change.  

PubMed

Membrane damage related to morphological change in Vero cells is a sensitive index of the composite biotoxicity of trace lipophilic chemicals. However, judging whether the morphological change in Vero cells happens and its ratio are difficult because it is not a quantitative characteristic. To find biomarkers of cell morphological change for quantitatively representing the ratio of morphological changed cell, the mechanism of cell membrane damage driven by typical lipophilic chemicals, such as trichlorophenol (TCP) and perfluorooctanesulphonate (PFOS), was explored. The ratio of morphologically changed cells generally increased with increased TCP or PFOS concentrations, and the level of four major components of phospholipids varied with concentrations of TCP or PFOS, but only the ratio of phosphatidylcholine (PC)/phosphatidylethanolamine (PE) decreased regularly as TCP or PFOS concentrations increased. Analysis of membrane proteins showed that the level of vimentin in normal cell membranes is high, while it decreases or vanishes after TCP exposure. These variations in phospholipid and membrane protein components may result in membrane leakage and variation in rigid structure, which leads to changes in cell morphology. Therefore, the ratio of PC/PE and amount of vimentin may be potential biomarkers for representing the ratio of morphological changed Vero cell introduced by trace lipophilic compounds, thus their composite bio-toxicity. PMID:25065828

Liao, Ting T; Wang, Lei; Jia, Ru W; Fu, Xiao H; Chua, Hong

2014-10-01

332

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

333

Systematic study of osteoblast and fibroblast response to roughness by means of surface-morphology gradients.  

PubMed

The surface roughness of a medical implant is of great importance since the surface is in direct contact with the host tissue (e.g. bone, fibrous tissue). The response of cells to roughness is different depending on the cell type. However, the influence of roughness on cell behavior has only rarely been systematically studied. We have developed a surface-modification process to produce roughness gradients that cover a wide range of roughness values on one substratum. Such gradients allow for systematic investigations of roughness on cell behavior. Gradients were fabricated using a two-step roughening and smoothening process, involving sandblasting and a subsequent chemical polishing step. In order to produce a set of identical surfaces we applied a replica technique. Cell experiments were carried out with rat calvarial osteoblasts (RCO) and human gingival fibroblasts (HGF). RCOs showed a significantly increased proliferation rate with increasing surface roughness. The footprint of osteoblasts varied in size at different positions on the gradient, remaining small on the rough end of the gradient and increasing considerably as the roughness decreased. HGF showed the opposite proliferation behavior, proliferation decreasing with increasing roughness. The fibroblast morphology was found to be similar to that seen for osteoblasts. PMID:17275082

Kunzler, Tobias P; Drobek, Tanja; Schuler, Martin; Spencer, Nicholas D

2007-04-01

334

DMPS reverts morphologic and mitochondrial damage in OK cells exposed to toxic concentrations of HgCl2.  

PubMed

Mercuric chloride (HgCl(2)) is a highly toxic compound, which can cause nephrotoxic damage. In the present study effects of HgCl(2) on mitochondria integrity and energy metabolism, as well as antidotal effects of 2,3-dimercaptopropane-1-sulfonate (DMPS) were investigated in the opossum kidney derived cell line (OK). OK cell monolayers were incubated during 0, 1, 3, 6, and 9 h in serum-free culture medium containing 15 microM HgCl(2), either in the absence or in the presence of 60 microM DMPS in a 1:4 ratio. Intracellular ATP content, MTT reduction, and HSP70/HSP90 induction were studied; confocal, transmission electron microscopy, and light microscopy studies were also performed. For confocal analysis, a mitochondrial selective probe (MitoTracker Red CMXH2Ros) was used. Antioxidant activity of DMPS was also studied by the scavenging of the free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) technique. A decrease of ATP content, an impaired ability to reduce tetrazolium, and dramatic changes on cellular and mitochondrial morphology, and energetic levels were found after either 6 or 9 h of HgCl(2) exposure. Increased expression of HSP90 and HSP70 were also seen. When OK cells were co-incubated with HgCl(2) and DMPS, cellular morphology, viability, intracellular ATP, and mitochondrial membrane potential were partially restored; a protective effect on mitochondrial morphology was also seen. DMPS also showed potent antioxidant activity in vitro. Mitochondrial protection could be the cellular mechanism mediated by DMPS in OK cells exposed to a toxic concentration of HgCl(2). PMID:17131097

Carranza-Rosales, Pilar; Guzmán-Delgado, Nancy E; Cruz-Vega, Delia E; Balderas-Rentería, Isaías; Gandolfi, A Jay

2007-05-01

335

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

PubMed

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; Akerfelt, Malin; Lötjönen, Jyrki; Nees, Matthias

2014-01-01

336

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.

Harma, Ville; Schukov, Hannu-Pekka; Happonen, Antti; Ahonen, Ilmari; Virtanen, Johannes; Siitari, Harri; Akerfelt, Malin; Lotjonen, Jyrki; Nees, Matthias

2014-01-01

337

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

338

APC/?-catenin-rich complexes at membrane protrusions regulate mammary tumor cell migration and mesenchymal morphology  

PubMed Central

Background The APC tumor suppressor is mutated or downregulated in many tumor types, and is prominently localized to punctate clusters at protrusion tips in migratory cells, such as in astrocytes where it has been implicated in directed cell motility. Although APC loss is considered an initiating event in colorectal cancer, for example, it is less clear what role APC plays in tumor cell motility and whether loss of APC might be an important promoter of tumor progression in addition to initiation. Methods The localization of APC and ?-catenin was analyzed in multiple cell lines, including non-transformed epithelial lines treated with a proteasome inhibitor or TGF? to induce an epithelial-to-mesenchymal transition (EMT), as well as several breast cancer lines, by immunofluorescence. APC expression was knocked down in 4T07 mammary tumor cells using lentiviral-mediated delivery of APC-specific short-hairpin (sh) RNAs, and assessed using quantitative (q) reverse-transcriptase (RT)-PCR and western blotting. Tumor cell motility was analyzed by performing wound-filling assays, and morphology via immunofluorescence (IF) and phase-contrast microscopy. Additionally, proliferation was measured using BrdU incorporation, and TCF reporter assays were performed to determine ?-catenin/TCF-mediated transcriptional activity. Results APC/?-catenin-rich complexes were observed at protrusion ends of migratory epithelial cells treated with a proteasome inhibitor or when EMT has been induced and in tumor cells with a mesenchymal, spindle-like morphology. 4T07 tumor cells with reduced APC levels were significantly less motile and had a more rounded morphology; yet, they did not differ significantly in proliferation or ?-catenin/TCF transcriptional activity. Furthermore, we found that APC/?-catenin-rich complexes at protrusion ends were dependent upon an intact microtubule cytoskeleton. Conclusions These findings indicate that membrane protrusions with APC/?-catenin-containing puncta control the migratory potential and mesenchymal morphology of mammary tumor cells and suggest that APC loss during later stages of tumor progression might impact tumor cell dissemination or colonization.

2013-01-01

339

Morphologic characterization and distribution of endocrine cells in the large intestine of the opossum Didelphis aurita (Wied-Neuwied, 1826).  

PubMed

This study was designed to investigate the morphology and distribution of argyrophil, argentaffins, and insulin-immunoreactive endocrine cells in the large intestine of the opossum Didelphis aurita. Fragments of the large intestine of 10 male specimens of the opossum D. aurita were collected, processed, and submitted for histochemistry, immunohistochemistry, and scanning electron microscopy. The tunics of the large intestine of D. aurita presented morphological characteristics that have already been described for eutherian mammals. The morphometric data showed that the inner circular layer of all portions and regions analyzed is thicker relative to the longitudinal layer, and these layers in the rectum are thicker compared to the cecum and ascending colon. The majority of mucus-secreting cells have acid and neutral mucins, suggesting that the production of mucus is mixed. The number of these cells increases in the region of the cecum toward the rectum. Important findings include the occurrence of argyrophil, argentaffins, and insulin-immunoreactive endocrine cells in all segments of the large intestine of the opossum (D. aurita). To the best of our knowledge, this is the first report about the presence of insulin-immunoreactive endocrine cells in the large intestine of the opossum (D. aurita). PMID:23810437

Dos Santos, Daiane Cristina Marques; Cupertino, Marli do Carmo; Novaes, Rômulo Dias; Soares, Ítalo Augusto da Costa; Fonseca, Cláudio César; da Matta, Sérgio Luis Pinto; Sartori, Sirlene Souza Rodrigues

2013-10-01

340

Synthetical bone-like and biological hydroxyapatites: a comparative study of crystal structure and morphology.  

PubMed

Phase composition, crystal structure and morphology of biological hydroxyapatite (BHAp) extracted from human mandible bone, and carbonated hydroxyapatite (CHAp), synthesized by the chemical precipitation method, were studied by x-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and Raman (R) spectroscopy techniques, combined with transmission electron microscopy (TEM). Structural and microstructural parameters were determined through Rietveld refinement of recorded XRD data, performed using the FullProf computing program, and TEM. Microstructural analysis shows anisotropic extension along the [00l] crystallographic direction (i.e. elongated crystallites shape) of both investigated samples. The average crystallite sizes of 10 and 8 nm were estimated for BHAp and CHAp, respectively. The FTIR and R spectroscopy studies show that carbonate ions substitute both phosphate and hydroxyl ions in the crystal structure of BHAp as well as in CHAp, indicating that both of them are mixed AB-type of CHAp. The thermal behaviour and carbonate content were analysed using thermogravimetric and differential thermal analysis. The carbonate content of about 1 wt.% and phase transition, at near 790 °C, from HAp to ?-tricalcium phosphate were determined in both samples. The quality of synthesized CHAp powder, particularly, the particle size distribution and uniformity of morphology, was analysed by a particle size analyser based on laser diffraction and field emission scanning electron microscopy, respectively. These data were used to discuss similarity between natural and synthetic CHAp. Good correlation between the unit cell parameters, average crystallite size, morphology, carbonate content and crystallographic positions of carbonate ions in natural and synthetic HAp samples was found. PMID:21659698

Markovi?, Smilja; Veselinovi?, Ljiljana; Luki?, Miodrag J; Karanovi?, Ljiljana; Bra?ko, Ines; Ignjatovi?, Nenad; Uskokovi?, Dragan

2011-08-01

341

Chinese Morphology: An Exploratory Study of Second Language Learners' Acquisition of Compounds  

Microsoft Academic Search

Research in the field of linguistics has focused on syntax and grammar, while studies related to morphology have been relatively underrepresented. However, recent developments in linguistics have prompted researchers' to pay greater attention to lexicon and morphology. The aim of this paper is two-fold. One objective is to provide, from the perspectives of theoretical linguistics, a descriptive machinery that could

Ming-chung Yu

342

Exploring urban morphology using multi-temporal urban growth data: a case study of Wuhan, China  

Microsoft Academic Search

Understanding temporal urban growth process is crucial to the interpretation of urban morphology and a key challenge for the study of rapid urbanization in contemporary China. As an evolutionary process of urban form or landscape, urban morphology helps us track the trend of urban form development, which is characterized by multi-temporality in terms of data. The increasingly improved multi-temporal data

Jianquan Cheng

2011-01-01

343

Modification of osteoarthritis by pulsed electromagnetic field—a morphological study  

Microsoft Academic Search

Objective: Hartley guinea pigs spontaneously develop arthritis that bears morphological, biochemical, and immunohistochemical similarities to human osteoarthritis. It is characterized by the appearance of superficial fibrillation by 12 months of age and severe cartilage lesions and eburnation by 18 months of age. This study examines the effect of treatment with a pulsed electromagnetic field (PEMF) upon the morphological progression of

D. McK Ciombor; R. K Aaron; S Wang; B Simon

2003-01-01

344

Atomic force microscopy, a powerful tool to study blend morphologies based on polyester resins  

Microsoft Academic Search

Atomic Force Microscopy (AFM) was an unusual but effective tool used to investigate the morphology of cured blends based on UP (unsaturated polyester). The pertinence of AFM was evaluated by studying four miscible UP\\/LPA (low profile additive)\\/ST (styrene) blend systems. The morphology of these cured blends before and after LPA solubilization was analogous in SEM (Scanning Electron Microscopy) and AFM.

C. Serré; M. Vayer; R. Erre; N. Boyard; C. Ollive

2001-01-01

345

Luminescence, absorption and morphology studies of laser-damage sites in silica glasses and coatings  

Microsoft Academic Search

The analysis of modifications induced by laser damage in optical materials is important for understanding the damage process. In this work, we study the morphological and structural modifications induced by a nano-second pulsed laser (355 and 1064nm) on fused silica samples (Suprasil, Herasil) and silica thin films (deposited by IP, IAD, EBD, IAD). The morphological changes are analyzed using optical

Laurent Gallais; Jeremie Capoulade; Frank Wagner; Helene Krol; Jean-Yves Natoli; Mireille Commandre; Saidislam Kurbanov

2005-01-01

346

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

Microsoft Academic Search

Combining elemental, chemical, molecular, and morphological imaging information from individual cells with a lateral resolution\\u000a well below 1?×?1 ?m2 is the current technological challenge for investigating the smallest dimensions of living systems. In the race for such\\u000a analytical performance, several techniques have been successfully developed; some use probes to determine given cellular contents\\u000a whereas others use possible interactions between cellular matter

Cyril Petibois

2010-01-01

347

Dye-sensitized solar cells based on semiconductor morphologies with ZnO nanowires  

Microsoft Academic Search

ZnO nanowires and structures that combine nanowires and nanoparticles were used as the wide band gap semiconducting photoelectrode in dye-sensitized solar cells (DSSCs). The nanowires provide a direct path from the point of photogeneration to the conducting substrate and offer alternative semiconductor network morphologies to those possible with sintered nanoparticles. Growing nanowires with dendrite-like branched structure greatly enhances their surface

Jason B. Baxter; Eray S. Aydil

2006-01-01

348

Mucocele-like tumor and columnar cell hyperplasia of the breast occurring in a morphologic continuum  

Microsoft Academic Search

INTRODUCTION: Mucocele-like tumor was originally described in 1986 as a benign breast proliferation consisting of multiple dilated cysts lined by cytologically bland, flat to cuboidal cells. Subsequent reports described the coexistence of, including the morphologic inter-transitions between, mucocele-like tumor and a variety of other breast proliferations, including intraductal carcinoma, invasive carcinoma, atypical ductal hyperplasia, and hyperplasia of the usual type.

Oluwole Fadare; M Rajan Mariappan

2008-01-01

349

No Relationship between Embryo Morphology and Successful Derivation of Human Embryonic Stem Cell Lines  

Microsoft Academic Search

BackgroundThe large number (30) of permanent human embryonic stem cell (hESC) lines and additional 29 which did not continue growing, in our laboratory at Karolinska Institutet have given us a possibility to analyse the relationship between embryo morphology and the success of derivation of hESC lines. The derivation method has been improved during the period 2002–2009, towards fewer xeno-components. Embryo

Susanne Ström; Kenny Rodriguez-Wallberg; Frida Holm; Rosita Bergström; Linda Eklund; Anne-Marie Strömberg; Outi Hovatta

2010-01-01

350

Endothelial cells undergo morphological, biomechanical, and dynamic changes in response to tumor necrosis factor-?  

PubMed Central

The immune response triggers a complicated sequence of events, one of which is release of the cytokine tumor necrosis factor-? (TNF-?) from stromal cells such as monocytes and macrophages. In this work we explored the biophysical effects of TNF-? on endothelial cells (ECs), including changes in cell morphology, biomechanics, migration, and cytoskeletal dynamics. We found that TNF-? induces a wide distribution of cell area and aspect ratio, with these properties increasing on average during treatment. Interestingly, aspect ratio peaks around 10 hours of exposure to TNF-?, corresponding also to a peak in exerted traction forces. Meanwhile, ECs treated with TNF-? soften, and we associate this with significant increases in estimated cellular volume. In addition, our evaluation of migratory dynamics demonstrates an inverse correlation between cell aspect ratio and migration speed after TNF-? treatment, suggesting that cell shape may be an important functional regulator of EC migration during an inflammatory response. Finally, we address the basic mechanics of how the reorganization of F-actin filaments occurs during TNF-? treatment, and we demonstrate a dynamic shift of existing actin filaments. Together, our results suggest a functional link between EC morphology, biomechanics, migration, and cytoskeletal dynamics during an inflammatory response.

Stroka, Kimberly M.; Vaitkus, Janina A.; Aranda-Espinoza, Helim

2012-01-01

351

Morphologic and phenotypic changes of human neuroblastoma cells in culture induced by cytosine arabinoside  

SciTech Connect

The effects of cytosine-arabinoside (ARA-C) on the growth and phenotypic expression of a new human neuroblastoma (NB) cell line (GI-ME-N) have been extensively tested. Low doses of ARA-C allowing more than 90% cell viability induce morphological differentiation and growth inhibition. Differentiated cells were larger and flattened with elongated dendritic processes; such cells appeared within 48 hours after a dose of ARA-C as low as 0.1 {mu}g/ml. The new morphological aspect reached the maximum expression after 5-6 days of culture being independent from the addition of extra drug to the culture. A decrease in ({sup 3}H)thymidine incorporation was also observed within 24 hours and the cell growth was completely inhibited on the sixth day. Moreover, ARA-C strongly inhibited anchorage-independent growth in soft agar assay. Membrane immunofluorescence showed several dramatic changes in NB-specific antigen expression after 5 days of treatment with ARA-C. At the same time ARA-C also modulated cytoskeletal proteins and slightly increased catecholamine expression. These findings suggest that noncytotoxic doses of ARA-C do promote the differentiation of GI-ME-N neuroblastoma cells associated with reduced expression of the malignant phenotype.

Ponzoni, M.; Lanciotti, M.; Melodia, A.; Casalaro, A.; Cornaglia-Ferraris, P. (G. Gaslini Children's Hospital, Genoa (Italy))

1989-03-01

352

Comparative sequential morphological analyses during in vitro chondrogenesis and osteogenesis of mesenchymal stem cells embedded in collagen gels.  

PubMed

Chondrogenesis and osteogenesis during fetal development and postnatal growth constitute one of the most interesting and complicated subjects in biology. In this study, bone marrow mesenchymal stem cells (MSCs) were embedded in collagen gel, cultured in chondrogenic or osteogenic medium, and compared morphologically during chondrogenic and osteogenic differentiation sequentially by light and electron microscopy and immunohistochemical examination. Before induction, the MSCs were dispersed and round in the collagen gel. At day 1, MSCs with a large number of short processes produced extracellular fibers whose immunoreactivity was positive for collagen type I. At day 3, the shape of MSCs changed from round to elongated. Gap junctions positive for connexin 43 were also observed. At day 7, remarkable morphological differences were first observed during chondrogenesis and osteogenesis. The shape of MSCs changed to polygonal without cell processes during chondrogenesis, while MSCs remained spindle shaped with long processes during osteogenesis. Concurrently, collagen type II during chondrogenesis and osteocalcin during osteogenesis were first detected. At day 21, chondrogenesis and osteogenesis of the MSC/collagen composite further progressed, respectively. In vitro chondrogenesis and osteogenesis using an MSC/collagen composite clarified the morphological differences. PMID:23325551

Ichinose, Shizuko; Tagami, Motoki; Muneta, Takeshi; Mukohyama, Hitoshi; Sekiya, Ichiro

2013-03-01

353

Lack of ?8 integrin leads to morphological changes in renal mesangial cells, but not in vascular smooth muscle cells  

PubMed Central

Background Extracellular matrix receptors of the integrin family are known to regulate cell adhesion, shape and functions. The ?8 integrin chain is expressed in glomerular mesangial cells and in vascular smooth muscle cells. Mice deficient for ?8 integrin have structural alterations in glomeruli but not in renal arteries. For this reason we hypothesized that mesangial cells and vascular smooth muscle cells differ in their respective capacity to compensate for the lack of ?8 integrin. Results Wild type and ?8 integrin-deficient mesangial cells varied markedly in cell morphology and expression or localization of cytoskeletal molecules. In ?8 integrin-deficient mesangial cells ?-smooth muscle actin and CTGF were downregulated. In contrast, there were no comparable differences between ?8 integrin-deficient and wild type vascular smooth muscle cells. Expression patterns of integrins were altered in ?8 integrin-deficient mesangial cells compared to wild type mesangial cells, displaying a prominent overexpression of ?2 and ?6 integrins, while expression patterns of the these integrins were not different between wild type and ?8 integrin-deficient vascular smooth muscle cells, respectively. Cell proliferation was augmented in ?8 integrin-deficient mesangial cells, but not in vascular smooth muscle cells, compared to wild type cells. Conclusions Our findings suggest that ?8 integrin deficiency has differential effects in mesangial cells and vascular smooth muscle cells. While the phenotype of vascular smooth muscle cells lacking ?8 integrin is not altered, mesangial cells lacking ?8 integrin differ considerably from wild type mesangial cells which might be a consequence of compensatory changes in the expression patterns of other integrins. This could result in glomerular changes in ?8 integrin-deficient mice, while the vasculature is not affected in these mice.

2010-01-01

354

Toker cells of the breast. Morphological and immunohistochemical characterization of 40 cases.  

PubMed

Toker cells are epithelial cells with clear cytoplasm usually free of cytologic atypia localized within the nipple epidermis. Rarely, they can be so numerous and atypical as to require a careful distinction from malignant cells of Paget's disease. The purpose of this paper was to better define the prevalence of these atypical Toker cells and to investigate phenotypic markers that can be helpful in the differential diagnosis with Paget's disease. Forty cases containing Toker cells were identified in the nipples of 390 patients (10.2%) who underwent complete breast mastectomy. In 24 cases (60%), Toker cells were cytologically bland and benign, disappearing after a few consecutive sections ("normal Toker cells"). In 11 cases (27.5%), Toker cells were more numerous and persistent on serial sections, still retaining bland cytologic features ("hyperplastic Toker cells"). In 5 cases (12.5%), hyperplastic Toker cells also became cytologically atypical ("hyperplastic and atypical Toker cells"). On immunohistochemistry, Toker cells were positive for estrogen (25/25) and progesterone (20/23) receptors, and negative for CD138 (18/19) and p53 (14/14); some hyperplastic and atypical Toker cells (4 cases) and hyperplastic Toker cells (1 case) showed faint immunoreactivity for HER2/NEU. For comparison, Paget's disease were negative for estrogen (6/10) and progesterone (7/10) receptors, and positive for CD138 (7/10), p53 (6/10), and HER2/NEU (9/10). Both Toker cells and Paget's disease stained positive for cytokeratin 7 and epithelial membrane antigen, and negative for p63. In conclusion, Toker cells are detectable in 10% of the nipples and are usually cytologically bland, but in 10% of the cases they can be morphologically atypical. The combined use of CD138/p53 is very helpful in distinguishing these atypical Toker cells from those of Paget's disease. PMID:18614197

Di Tommaso, Luca; Franchi, Giada; Destro, Annarita; Broglia, Fabiana; Minuti, Francesco; Rahal, Daoud; Roncalli, Massimo

2008-09-01

355

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

356

Block copolymer morphology formation on topographically complex surfaces: a self-consistent field theoretical study.  

PubMed

A self-consistent field theoretic study is performed to study morphological development of lamellae-forming diblock copolymers on substrates with a well-defined roughness, modeled as trenches of varying depth and width engraved into the substrates. There are three possible lamellar orientations observed: horizontal lamellae, vertical lamellae that are parallel to the trench direction, and vertical lamellae that are perpendicular to the trench direction. Which of these three morphologies formed depends upon the trench width and surface affinity; however, trench depth has a relatively insignificant effect on the morphological development. Therefore, tuning trench width, but not trench depth, should allow for a reduction of the morphological defect density in directed self-assembly of lamellar morphology of diblock copolymers. PMID:24470333

Ye, Xianggui; Edwards, Brian J; Khomami, Bamin

2014-04-01

357

Growth Factor Modulation of Substrate-Specific Morphological Patterns in Aplysia Bag Cell Neurons  

PubMed Central

Components of the extracellular matrix (ECM) can act not only as passive substrates for neuronal attachment and outgrowth but also as active sites for signal transduction. Thus, specific ECM components may modulate effects of growth factors (GFs) that play an important role in structural changes in development and adult neuronal plasticity. In this study we examined the interaction of cultured Aplysia bag cell neurons (BCNs) with components of ECM and different GFs. Different ECM substrata induce a substrate-specific BCN morphology: BCNs grown on collagen or poly-l-lysine have larger soma diameter and more extensive neurite outgrowth than BCNs grown on laminin or fibronectin. BCNs also interact in a substrate-dependent way with GFs: BDNF treatment leads to a reduction of outgrowth on poly-l-lysine but an enhancement on fibronectin and laminin. CNTF reduces the soma diameter on collagen IV but enlarges it on laminin or fibronectin. In contrast, NGF induces a reduction of both soma diameter and outgrowth, on all substrata. Plating of BCNs in the presence of anti-?1-integrin reduces adhesion to fibronectin but does not change outgrowth. In contrast, RGD peptides block adhesion to laminin and poly-l-lysine and, additionally, reduce outgrowth on laminin. These data suggest that BCNs use different ?1-integrin-dependent as well as RGD-dependent mechanisms for adhesion and outgrowth on different ECM substrata, providing possible sites of modulation by specific GFs.

Gruenbaum, Lore M.; Carew, Thomas J.

1999-01-01

358

Morphological Characterization of Low-Bandgap Crystalline Polymer:PCBM Bulk Heterojunction Solar Cells  

NASA Astrophysics Data System (ADS)

Understanding the morphology of polymer-based bulk heterojunction (BHJ) solar cells is key to improving device efficiencies. Blends of a low-bandgap silole-containing conjugated polymer, poly[(4,4'-bis(2-ethylhexyl)dithieno[3,2-b;2',3'-d]silole)-2,6-diyl-alt-(4,7-bis(2-thienyl)-2,1,3-benzothiadiazole)-5,5'-diyl] (PSBTBT) with phenyl-C61-butyric acid methyl ester (PCBM) were investigated using different processing conditions. Scanning force microscopy, X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, dynamic secondary ion mass spectrometry and neutron reflectivity studies showed that thermal annealing did not induce obvious changes in the structure of the active layer. Grazing-incidence X-ray diffraction and small-angle neutron scattering showed that the crystallization of PSBTBT and segregation of PCBM occurred during spin coating, and a brief thermal annealing increased the ordering of PSBTBT and enhanced the segregation of the PCBM, forming domains with 10-nm in size, leading to an improvement in photovoltaic performance.

Lu, Haiyun; Russell, Thomas

2011-03-01

359

Growth factor modulation of substrate-specific morphological patterns in Aplysia bag cell neurons.  

PubMed

Components of the extracellular matrix (ECM) can act not only as passive substrates for neuronal attachment and outgrowth but also as active sites for signal transduction. Thus, specific ECM components may modulate effects of growth factors (GFs) that play an important role in structural changes in development and adult neuronal plasticity. In this study we examined the interaction of cultured Aplysia bag cell neurons (BCNs) with components of ECM and different GFs. Different ECM substrata induce a substrate-specific BCN morphology: BCNs grown on collagen or poly-L-lysine have larger soma diameter and more extensive neurite outgrowth than BCNs grown on laminin or fibronectin. BCNs also interact in a substrate-dependent way with GFs: BDNF treatment leads to a reduction of outgrowth on poly-L-lysine but an enhancement on fibronectin and laminin. CNTF reduces the soma diameter on collagen IV but enlarges it on laminin or fibronectin. In contrast, NGF induces a reduction of both soma diameter and outgrowth, on all substrata. Plating of BCNs in the presence of anti-beta1-integrin reduces adhesion to fibronectin but does not change outgrowth. In contrast, RGD peptides block adhesion to laminin and poly-L-lysine and, additionally, reduce outgrowth on laminin. These data suggest that BCNs use different beta1-integrin-dependent as well as RGD-dependent mechanisms for adhesion and outgrowth on different ECM substrata, providing possible sites of modulation by specific GFs. PMID:10492011

Gruenbaum, L M; Carew, T J

1999-01-01

360

Assessing epithelial cell nuclear morphology by using azimuthal light scattering spectroscopy  

NASA Astrophysics Data System (ADS)

We describe azimuthal light scattering spectroscopy (?/LSS), a novel technique for assessing epithelial-cell nuclear morphology. The difference between the spectra measured at azimuthal angles ?=0° and ?=90° preferentially isolates the single backscattering contribution due to large (˜10 ?m) structures such as epithelial cell nuclei by discriminating against scattering from smaller organelles and diffusive background. We demonstrate the feasibility of using ?/LSS for cancer detection by showing that spectra from cancerous colon tissue exhibit significantly greater azimuthal asymmetry than spectra from normal colonic tissues.

Yu, Chung-Chieh; Lau, Condon; Tunnell, James W.; Hunter, Martin; Kalashnikov, Maxim; Fang-Yen, Christopher; Fulghum, Stephen F.; Badizadegan, Kamran; Dasari, Ramachandra R.; Feld, Michael S.

2006-11-01

361

Effects of vitamin B-6 deficiency on morphological changes in dendritic trees of Purkinje cells in developing cerebellum of rats.  

PubMed

The effect of maternal vitamin B-6 deficiency on the morphological changes in the dendritic growth of Purkinje cells of progeny was studied at four different ages (12, 15, 21, and 50 days) of postnatal development. By day 10, rat pups in the deficient groups (0.6 or 1.0 mg pyridoxine . HCl/kg diet) began to show gross neurological symptoms of the deficiency and before weaning approximately 12% of the pups in the 0.6 group had died. At each age studied, body weights were less and brain-body weight ratios were greater in the deficient groups compared to control (7.0 mg pyridoxine . HCl/kg diet) groups. Morphological changes of the Purkinje cell dendritic field, as determined from camera lucida drawings of Golgi-Cox impregnated cells of the mid-sagittal vermis, indicated significantly smaller width, height and area in the deficient groups compared to the control. Stereological measurements showed that dendritic branching density was significantly less in the 0.6 group compared with the 1.0 and 7.0 groups. The total length of Purkinje cell dendrites per cell was significantly reduced in the deficient groups compared to the 7.0 group. Qualitative analyses of photomicrographs of Purkinje cells indicated more dendritic and somatic aberrations in the deficient groups than in the control. Dendritic trees were larger in size and more complex in the 7.0 group compared to the deficient groups. The findings indicate that maternal vitamin B-6 deficiency interferes with normal development of the Purkinje cell dendrites. PMID:7229735

Chang, S J; Kirksey, A; Morré, D M

1981-05-01

362

Early B cell factor 1 regulates adipocyte morphology and lipolysis in white adipose tissue.  

PubMed

White adipose tissue (WAT) morphology characterized by hypertrophy (i.e., fewer but larger adipocytes) associates with increased adipose inflammation, lipolysis, insulin resistance, and risk of diabetes. However, the causal relationships and the mechanisms controlling WAT morphology are unclear. Herein, we identified EBF1 as an adipocyte-expressed transcription factor with decreased expression/activity in WAT hypertrophy. In human adipocytes, the regulatory targets of EBF1 were enriched for genes controlling lipolysis and adipocyte morphology/differentiation, and in both humans and murine models, reduced EBF1 levels associated with increased lipolysis and adipose hypertrophy. Although EBF1 did not affect adipose inflammation, TNF? reduced EBF1 gene expression. High-fat diet intervention in Ebf1(+/-) mice resulted in more pronounced WAT hypertrophy and attenuated insulin sensitivity compared with wild-type littermate controls. We conclude that EBF1 is an important regulator of adipose morphology and fat cell lipolysis and may constitute a link between WAT inflammation, altered lipid metabolism, adipose hypertrophy, and insulin resistance. PMID:24856929

Gao, Hui; Mejhert, Niklas; Fretz, Jackie A; Arner, Erik; Lorente-Cebrián, Silvia; Ehrlund, Anna; Dahlman-Wright, Karin; Gong, Xiaowei; Strömblad, Staffan; Douagi, Iyadh; Laurencikiene, Jurga; Dahlman, Ingrid; Daub, Carsten O; Rydén, Mikael; Horowitz, Mark C; Arner, Peter

2014-06-01

363

Morphological studies of DBSA-doped polyaniline/PVC blends.  

PubMed

Solution blending technique has been used to synthesize dodecylbenzenesulfonic acid (DBSA)-doped polyaniline (PAND)/poly-vinyl chloride (PVC) blends by two methods, namely redoping method (PANDR/PVC blends) and aqueous polymerization method (PANDA/PVC blends). PANDR/PVC blends show improved mechanical properties as compared to PANDA/PVC blends, which show brittle nature of the films. However, by increasing concentration of PANDR in the PVC matrix, PANDR/PVC blend films are becoming more rigid due to increases in the modulus of elasticity. Irradiation of blend samples by electron beam used during scanning electron microscopy (SEM) analyses has changed the morphology of PANDA/PVC blend films due to dehydrochlorination of free PVC, whereas PANDR/PVC blends remain unaffected during irradiation by electron beam. PMID:20601353

Afzal, Asma Binat; Akhtar, Muhammad Javed; Ahmad, Maqsood

2010-01-01

364

ErbB receptor activation, cell morphology changes, and apoptosis induced by anti-Her2 monoclonal antibodies.  

PubMed

A panel of mAbs were generated against the purified soluble form of erbB2/Her2 receptor, corresponding to the extracellular region of the receptor, and examined for their ability to mimic the receptor ligand. Some of the mAbs strongly induced tyrosine phosphorylation of 180-185 kDa proteins, including not only Her2 but also Her3 and Her4 receptors, when they were expressed on the surface of breast cancer cells. These mAbs do not cross-react with Her3 or Her4 as demonstrated by competition study. Receptor phosphorylation was also observed with the cell lines transfected with Her2 or a chimeric receptor consisting of the extracellular domain of Her2 and the transmembrane and cytoplasmic domains of epidermal growth factor receptor. Selected mAbs were tested for their ability to change cell morphology, and one specific mAb, mAb74, i