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1

Morphological study of the TK cholangiocarcinoma cell line with three-dimensional cell culture.  

PubMed

Cholangiocarcinoma is an intractable carcinoma originating from the bile duct epithelium. To gain an understanding of the cell biology of cholangiocarcinoma, in vitro cell culture is valuable. However, well?characterized cell lines are limited. In the present study, the morphology of the TK cholangiocarcinoma cell line was analyzed by three?dimensional culture. Dispersed TK cells were injected into a gelatin mesh scaffold and cultivated for 3?20 days. The morphology of the TK cells was investigated by phase?contrast microscopy, optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). TK cells were observed to proliferate three-dimensionally in the scaffold. The cells exhibited a globoid structure and attached to the scaffold. The SEM observation demonstrated typical microvilli and plicae on the surface of the structure. Light microscopy and TEM confirmed intercellular and cell?to?scaffold attachment in the three?dimensional mesh. The culture also exhibited the formation of a duct-like structure covered by structured microvilli. In conclusion, three?dimensional culture of TK cells demonstrated the morphological characteristics of cholangiocarcinoma in vitro. Production of high levels of carbohydrate antigen (CA)19?9, CA50 and carcinoembryonic antigen was previously confirmed in the TK cell line. As a characteristic morphology was demonstrated in the present study, the TK cholangiocarcinoma cell line may be useful as an experimental model for further study of cholangiocarcinoma. PMID:24535710

Akiyoshi, Kohei; Kamada, Minori; Akiyama, Nobutake; Suzuki, Masafumi; Watanabe, Michiko; Fujioka, Kouki; Ikeda, Keiichi; Mizuno, Shuichi; Manome, Yoshinobu

2014-04-01

2

Morphological study on pigmented cells in the horse testis.  

PubMed

One of the most attractive characteristics of a horse testis is the change of the weight during development. As the testicular weight changes and the number of Leydig cells decreases, pigments appear in interstitial tissues. In the present study, the characteristics of the pigments found in the interstitial tissues were examined histochemically and ultrastructurally. Specific stainings indicated that the pigmented granules showed almost all of the histological and histochemical characteristics of ceroid or ceroid-like pigment. The cells showed positive reaction for acid phosphatase while the pigmented cells contained a lot of lysosomes ultrastructurally. These results suggest that macrophages might phagocytize Leydig cells, and store their digested materials as ceroid-like pigment. PMID:10563302

Murabayashi, H; Hondo, E; Kitamura, N; Furuoka, H; Taguchi, K; Nambo, Y; Yamada, J

1999-10-01

3

Effects of dendritic morphology on CA3 pyramidal cell electrophysiology: a simulation study  

Microsoft Academic Search

We investigated the effect of morphological differences on neuronal firing behavior within the hippocampal CA3 pyramidal cell family by using three-dimensional reconstructions of dendritic morphology in computational simulations of electrophysiology. In this paper, we report for the first time that differences in dendritic structure within the same morphological class can have a dramatic influence on the firing rate and firing

Jeffrey L. Krichmar; Slawomir J. Nasuto; Ruggero Scorcioni; Stuart D. Washington; Giorgio A. Ascoli

2002-01-01

4

Quantitative analysis of dendritic morphology of the alpha and delta retinal ganglion cells in the rat: A cell classification study  

Microsoft Academic Search

Type I retinal ganglion cells in the rat have been classified into several groups based on the cell body size and dendritic morphology. Considerable overlap and heterogeneity within groups have been reported, which is especially obvious for the morphology of the dendritic tree. For that purpose, we analysed quantitatively the dendritic morphology of the alpha and delta rat retinal ganglion

Nebojša T. Miloševi?; Dušan Ristanovi?; Herbert F. Jelinek; Katarina Rajkovi?

2009-01-01

5

Changes in lung morphology and cell number in radiation pneumonitis and fibrosis: a quantitative ultrastructural study  

SciTech Connect

We used stereologic-morphometric techniques to obtain a detailed quantitative picture of the changes in lung ultrastructure of rats at 12 and 26 weeks after unilateral thoracic irradiation with 3000 cGy. At 12 weeks post-radiation, the total number type 1 epithelial cells, type 2 epithelial cells and capillary endothelial cells were decreased 50-70%, total type 1 epithelial and capillary surface areas were decreased 55-60%, and the total volume of intracapillary blood was decreased 75%. The interstitial cells and matrix together accounted for more than 9% of the peripheral lung tissue volume including air, compared to 3% in controls. The numerical density of interstitial cells was increased to 3-fold the control value. The numerical density of interstitial cells was increased to 3-fold the control value. Although fibroblasts still comprised the largest interstitial cell subgroup, the numerical density of mast cells was increased over 150-fold and other inflammatory and immune cells were increased to a lesser extent. At 26 weeks post-radiation, the number, volume, and surface area of the type 1 epithelium and capillary endothelium had further decreased to only 5-10% of control values. The total number of type 2 epithelial cells was reduced by 75% but the volume density was actually increased because of a 4-fold increase in the mean cell volume. The interstitial cells and matrix now comprised over 77% of total peripheral lung tissue volume including air as compared to 6% in controls. Mast cells and plasma cells comprised 11% and 19% of all interstitial cells respectively and the densities of these cells were 540 and 180-fold the control value respectively. The relation of these morphometric findings to the results of previous morphologic studies is discussed.

Vergara, J.A.; Raymond, U.; Thet, L.A.

1987-05-01

6

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. PMID:199607

Fowler, S; Shio, H; Wolinsky, H

1977-01-01

7

Study of Cd-chalcogenide\\/ferri-ferrocyanide photoelectrochemical cells - Effect of surface morphology and added salt  

Microsoft Academic Search

The authors carried out an investigation of the Cd-chalcogenide\\/ferri-ferrocyanide photoelectrochemical cells. In particular, the effect of surface morphology and the effect of added salts upon the characteristics of these cells were investigated. Successive etching with Brâ (3%)\\/methanol, aqua regia, and finally photoetching increases the surface roughness of CdSe (CdS, CdTe) which has a marked effect on the cell characteristics in

R. Tenne

1983-01-01

8

Study of Cd-chalcogenide/ferri-ferrocyanide photoelectrochemical cells: effect of surface morphology and added salt  

SciTech Connect

The authors carried out an investigation of the Cd-chalcogenide/ferri-ferrocyanide photoelectrochemical cells. In particular, the effect of surface morphology and the effect of added salts upon the characteristics of these cells were investigated. Successive etching with Br/sub 2/ (3%)/methanol, aqua regia, and finally photoetching increases the surface roughness of CdSe (CdS, CdTe) which has a marked effect on the cell characteristics in the ferri-ferrocyanide electrolyte (and polysulfide electrolyte as well). In contrast with polysulfide electrolyte, added salts decrease the output stability of the cell and the onset potential for the photocurrent, which can be explained by the removal of the physiosorbed ferrocyanide ions from the electrode surface by the ions of the salt. On increasing the surface roughness of the electrode, while keeping the salt concentration unchanged, the output stability and the onset potential were increased. A kinetic model is used to explain these phenomena. Thus, added salts can be used to probe the strength of the adsorption of the active electrolyte on the surface of the photoelectrode. Finally, we report on the surface morphology of CdSe and CdTe after irradiation in ferri-ferrocyanide solution and compare our findings to surface morphologies which were observed previously with the help of photoelectrochemical etching (photoetching). It is found that small rectangular crystallites, probably of cadmium ferrocyanide, deposit on the crystal surface during the photocorrosion process in addition to elemental Se(Te).

Tenne, R.

1983-11-01

9

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. PMID:24476851

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

2014-01-01

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

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

12

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

13

Menstruum induces changes in mesothelial cell morphology.  

PubMed

In previous studies, we have shown that menstrual endometrium preferentially adheres to the subepithelial lining of the peritoneum. It remains to be elucidated, however, whether this damage is preexisting or inflicted by the menstrual tissue itself. We hypothesized that the menstrual tissue itself damages the peritoneum. To investigate this, the viability of menstrual endometrial tissue in peritoneal fluid (PF) was evaluated and the morphologic changes in the mesothelial cells were studied by in vitro cocultures of menstruum with mesothelial cell monolayers. Menstruum was collected with a menstrual cup. Endometrial tissue was isolated from the menstruum, resuspended in culture medium or in the cell-free fraction of PF and cultured for 24, 48 or 72 h. A 3(4, 5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide (MTT) assay was performed to obtain a relative measure of viable adhered endometrial cells. Mesothelial cells isolated from human omental tissue were cultured on Matrigel or uncoated plastic. At confluence, overnight cocultures were performed and scanning electron microscopy was used to evaluate the morphologic changes. The viability of endometrial fragments was 84% (n = 36, p < 0.05), 82% (n = 27, not significant) and 104% (n = 14, not significant) when cultured in the cell-free fraction of PF for 24, 48 and 72 h, respectively, when compared to medium with 10% fetal calf serum. Menstrual endometrial fragments or menstrual serum added to and cocultured with mesothelial cells induced severe morphologic alterations of the latter, including retraction, shrinking and gap formation. Similar morphologic changes were observed when mesothelial cells were cocultured with menstrual endometrial fragments in PF or in culture inserts. Incubation with conditioned medium from cultured menstrual endometrium induced similar but less pronounced changes in morphology. In conclusion, menstrual endometrial fragments remain viable in PF in vitro for at least 72 h. Antegradely shed menstruum induces changes in mesothelial cell morphology, including retraction and shrinking with exposure of the underlying surface. These findings suggest that menstruum is harmful to the peritoneal lining. Therefore, by local destruction of the mesothelial layer, menstrual endometrium is able to create sites for adhesion. PMID:10895021

Koks, C A; Demir Weusten, A Y; Groothuis, P G; Dunselman, G A; de Goeij, A F; Evers, J L

2000-01-01

14

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.

15

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. PMID:22272215

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

2012-01-01

16

Isolation of Mesophyll Cells and Bundle Sheath Cells from Digitaria sanguinalis (L.) Scop. Leaves and a Scanning Microscopy Study of the Internal Leaf Cell Morphology 1  

PubMed Central

A technique is described for the separation of mesophyll and bundle sheath cells from Digitaria sanguinalis leaves and evidence for separation is given with light and scanning electron micrographs. Gentle grinding of fully differentiated leaves in a mortar releases mesophyll cells which are isolated on nylon nets by filtration. More extensive grinding of the remaining tissue yields bundle sheath strands which are isolated by filtration with stainless steel sieves and nylon nets. Further grinding of bundle sheath strands in a tissue homogenizer releases bundle sheath cells which are collected on nylon nets. Percentage of purity derived from cell counts and yield data on a chlorophyll basis are given. The internal leaf cell morphology is presented in scanning electron micrographs and compared with light micrographs of fully-differentiated D. sanguinalis leaves. In leaves of plants which possess the C4-dicarboxylic acid cycle of photosynthesis, the relationship of leaf morphology to photosynthesis in mesophyll and bundle sheath cells is considered, and the hypothesis is presented that as atmospheric CO2 enters a leaf about 85% is fixed by the C4-dicarboxylic acid cycle in the mesophyll cells and 10 to 15% is fixed by the reductive pentose phosphate cycle in the bundle sheath cells. A technique also is given for the isolation of mesophyll cells from spinach leaves. Images PMID:16657571

Edwards, Gerald E.; Black, Clanton C.

1971-01-01

17

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

PubMed

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

Edwards, G E; Black, C C

1971-01-01

18

The role of trophoblastic binucleate cells in implantation in the goat: a morphological study.  

PubMed Central

In the goat conceptus individual intra-epithelial trophectodermal binucleate cells first appear 18 days post coitum and their incidence rapidly increases where the trophectoderm is apposed to the caruncular and intercaruncular sites of initial attachment to the uterine epithelium. Special staining techniques reveal that these cells, when mature, contain prominent Golgi bodies and numerous characteristic granules. Our evidence shows that at 19 days post coitum the binucleate cells migrate to the microvillar junction and fuse with individual uterine epithelial cells to form hybrid feto-maternal trinucleate cells. It is proposed that subsequent continued binucleate cell migration and fusion with trinucleate cells produce the syncytial plaques typical of the remainder of pregnancy. It is further suggested that the fusion is important in facilitating the delivery of the characteristic granules to the base of the uterine epithelial layer with subsequent exocytosis of their contents into maternal tissue. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11 Figs. 12-13 Figs. 14-16 PMID:1707046

Wango, E O; Wooding, F B; Heap, R B

1990-01-01

19

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

PubMed Central

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

2014-01-01

20

A simulation study on the effects of dendritic morphology on layer V prefrontal pyramidal cell firing behavior.  

PubMed

Pyramidal cells, the most abundant neurons in neocortex, exhibit significant structural variability across different brain areas and layers in different species. Moreover, in response to a somatic step current, these cells display a range of firing behaviors, the most common being (1) repetitive action potentials (Regular Spiking-RS), and (2) an initial cluster of 2-5 action potentials with short interspike interval (ISIs) followed by single spikes (Intrinsic Bursting-IB). A correlation between firing behavior and dendritic morphology has recently been reported. In this work we use computational modeling to investigate quantitatively the effects of the basal dendritic tree morphology on the firing behavior of 112 three-dimensional reconstructions of layer V PFC rat pyramidal cells. Particularly, we focus on how different morphological (diameter, total length, volume, and branch number) and passive [Mean Electrotonic Path length (MEP)] features of basal dendritic trees shape somatic firing when the spatial distribution of ionic mechanisms in the basal dendritic trees is uniform or non-uniform. Our results suggest that total length, volume and branch number are the best morphological parameters to discriminate the cells as RS or IB, regardless of the distribution of ionic mechanisms in basal trees. The discriminatory power of total length, volume, and branch number remains high in the presence of different apical dendrites. These results suggest that morphological variations in the basal dendritic trees of layer V pyramidal neurons in the PFC influence their firing patterns in a predictive manner and may in turn influence the information processing capabilities of these neurons. PMID:25278837

Psarrou, Maria; Stefanou, Stefanos S; Papoutsi, Athanasia; Tzilivaki, Alexandra; Cutsuridis, Vassilis; Poirazi, Panayiota

2014-01-01

21

A simulation study on the effects of dendritic morphology on layer V prefrontal pyramidal cell firing behavior  

PubMed Central

Pyramidal cells, the most abundant neurons in neocortex, exhibit significant structural variability across different brain areas and layers in different species. Moreover, in response to a somatic step current, these cells display a range of firing behaviors, the most common being (1) repetitive action potentials (Regular Spiking—RS), and (2) an initial cluster of 2–5 action potentials with short interspike interval (ISIs) followed by single spikes (Intrinsic Bursting—IB). A correlation between firing behavior and dendritic morphology has recently been reported. In this work we use computational modeling to investigate quantitatively the effects of the basal dendritic tree morphology on the firing behavior of 112 three-dimensional reconstructions of layer V PFC rat pyramidal cells. Particularly, we focus on how different morphological (diameter, total length, volume, and branch number) and passive [Mean Electrotonic Path length (MEP)] features of basal dendritic trees shape somatic firing when the spatial distribution of ionic mechanisms in the basal dendritic trees is uniform or non-uniform. Our results suggest that total length, volume and branch number are the best morphological parameters to discriminate the cells as RS or IB, regardless of the distribution of ionic mechanisms in basal trees. The discriminatory power of total length, volume, and branch number remains high in the presence of different apical dendrites. These results suggest that morphological variations in the basal dendritic trees of layer V pyramidal neurons in the PFC influence their firing patterns in a predictive manner and may in turn influence the information processing capabilities of these neurons. PMID:25278837

Psarrou, Maria; Stefanou, Stefanos S.; Papoutsi, Athanasia; Tzilivaki, Alexandra; Cutsuridis, Vassilis; Poirazi, Panayiota

2014-01-01

22

[A morphological study of rat liver cells after the administration of phenobarbital and ziksorin].  

PubMed

Male Wistar rats were inducted with phenobarbital and ziksorin. The inducing effect has been shown by hepatocyte hypertrophy involving the cytoplasm and nuclei. After phenobarbital injection cytoplasmic hypertrophy was due to redistribution of the plastic material in favour of the smooth-surface endoplasmic reticulum (SER). This redistribution occurred with the decrease of the energy forming and external synthetic functions of hepatocytes. After ziksorin injection SER hyperplasia was combined with proportional hyperplasia of the whole cytoplasmic organelles of the liver cells. This points to more optimal response of hepatocytes after ziksorin induction as compared with phenobarbital. Therefore, ziksorin can be recommended for clinical practice if it is necessary to stimulate processes of reparative regeneration in the liver. PMID:1288707

Zakharova, M V; Shkurupi?, V A

1992-10-01

23

A morphological study of a human adenocarcinoma cell line (HT29) differentiating in culture. Similarities to intestinal embryonic development.  

PubMed

HT29 cells, a human adenocarcinoma cell line, when grown in Dulbecco's modified Eagle's medium (DMEM), form a multilayer of morphologically undifferentiated and unpolarized cells. However, when DMEM is replaced by RPMI medium, after 1-4 passages, a large amount of intracellular (ICL) and intercellular (ITCL) or secondary lumina (SL) are observed. These are detected in the light microscope and appear in the electron microscope as spherical structures embedded inside a multilayer of cells and bordered with microvilli. After 4-15 passages in RPMI, the cells retain the same pattern of cell growth but in addition exhibit apical brush-border microvilli and reveal a well developed belt of tight junctions. After 15 passages a single layer of polarized cells is clearly observed and a large number of 'domes' appeared. These results show that each of these culture types mimics morphologically specific stages described during intestinal ontogenesis between the 9th and the 16th week in the human embryo. PMID:2271997

Hekmati, M; Polak-Charcon, S; Ben-Shaul, Y

1990-09-01

24

Cell morphology in injectable nanostructured biosynthetic hydrogels.  

PubMed

Even though inducing structural features on the nanometric scale has been shown to be a powerful tool in tissue engineering, almost all nanostructuring techniques available today cannot be applied to injectable hydrogel scaffolds. The current research explores such a novel technique and its effect on scaffold's properties, cell morphology, and cell-material interaction. Nanostructuring is achieved by covalently binding Pluronic(®) F127 molecules to biosynthetic hydrogels. Analysis of cell morphology revealed spindled cell morphologies at day 4 in culture. The bound Pluronic(®) F127 diminished the swelling ability and enhanced the Young modulus, thus indicating that the bound molecules crosslink the hydrogel. The relation between matrix characteristics and cell morphology was analyzed and the importance of nanostructuring was demonstrated. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 4371-4379, 2014. PMID:24678010

Yom-Tov, Ortal; Seliktar, Dror; Bianco-Peled, Havazelet

2014-12-01

25

Morphological and functional platelet abnormalities in Berkeley sickle cell mice  

Microsoft Academic Search

Berkeley sickle cell mice are used as animal models of human sickle cell disease but there are no reports of platelet studies in this model. Since humans with sickle cell disease have platelet abnormalities, we studied platelet morphology and function in Berkeley mice (SS). We observed elevated mean platelet forward angle light scatter (FSC) values (an indirect measure of platelet

Arun S. Shet; Thomas J. Hoffmann; Marketa Jirouskova; Christin A. Janczak; Jacqueline R. M. Stevens; Adewole Adamson; Narla Mohandas; Elizabeth A. Manci; Therese Cynober; Barry S. Coller

2008-01-01

26

Study of the Ability of Phenacetin, Acetaminophen, and Aspirin to Induce Cytotoxicity, Mutation, and Morphological Transformationin C3H\\/10TV2 Clone 8 Mouse Embryo Cells1  

Microsoft Academic Search

Use of the analgesic compounds acetylsalicyclic acid (aspirin), phen- acetin, and acetaminophen has been correlated with increased risk of renal cancer in humans. Hence, we studied these compounds for ability to induce cytotoxicity, mutation to ouabain resistance, and morphological transformation in cultured C3H\\/10T'\\/2 clone 8 (lOT'\\/i) mouse embryo cells. All three compounds were cytotoxic from 0.5-mg\\/ml to 2-mg\\/ml concentrations as

Steven R. Patierno; Norman L. Lehman; Brian E. Henderson; Joseph R. Landolph

27

The morphology of the denuded epidermal basal cell layer of the hairless mouse after different preparation methods. A scanning and transmission electron microscopical study.  

PubMed

The denuded basal cell layer of the hairless mouse epidermis is described in the present scanning (SEM) and transmission electron microscopical (TEM) study. The suprabasal layers were removed mechanically after trypsinization or by extracellular calcium depletion. Trypsinization before removal of the suprabasal cells caused the basal cells to shrink. Characteristic surface plication and hemi-desmosomal attachment to the basement membrane were generally preserved. SEM revealed partly maintained intercellular bridging, whereas by TEM such contacts were absent because half desmosomes were internalized. Total calcium depletion induced more serious damage to the basal cell surface, which was smooth with apparent perforations. However, cell bridges, and occasional desmosomes were present. The cell interior demonstrated important cellular injury. If the calcium deprived explants were allowed to recover in calcium-containing medium, the cells acquired an activated "regenerative" morphology, without junctions, similar to that observed in wound healing. Epidermal non-keratinocytes were seen only after trypsinization. Control experiments revealed that they adapted poorly to organ culture conditions. By TEM, we observed several interesting aspects of the differences, between dark and clear basal keratinocytes. This was unexpected because fixation studies had shown, that with the present fixation method, typical dark and clear cells do not occur in untreated epidermis. We believe that membrane injury through mechanical stripping of partly adhering epidermal layers induced "clear cells", whereby the neighboring cells appeared darker. This provides additional evidence as to the origin of the two sub-populations, dark and clear basal cells. The clear cells may be injured cells, caused by cell damage, and not by processes of cellular differentiation. The results of the present investigation supports the view that basal keratinocytes have a polygonal shape with numerous free surface extensions and they are anchored to the basement membrane with "foot pads". Our study also shows that SEM of the epidermal basal layer might be feasible. Various artifacts, however, must be considered, depending on the denudation method used. We prefer trypsinization to calcium depletion because it is less time-consuming and results in a cell morphology which in TEM is comparable to that of basal cells in untreated whole epidermis. Extra-cellular calcium depletion, however, might be useful as a method to prepare single cell suspensions for flow cytometry. Restoration of a normal calcium concentration after stripping, provides an opportunity to mimic wound healing in situ, as an alternative t PMID:2570485

Glasø, M; Håskjold, E

1989-01-01

28

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

29

A novel mechanotactic 3D modeling of cell morphology  

NASA Astrophysics Data System (ADS)

Cell morphology plays a critical role in many biological processes, such as cell migration, tissue development, wound healing and tumor growth. Recent investigations demonstrate that, among other stimuli, cells adapt their shapes according to their substrate stiffness. Until now, the development of this process has not been clear. Therefore, in this work, a new three-dimensional (3D) computational model for cell morphology has been developed. This model is based on a previous cell migration model presented by the same authors. The new model considers that during cell–substrate interaction, cell shape is governed by internal cell deformation, which leads to an accurate prediction of the cell shape according to the mechanical characteristic of its surrounding micro-environment. To study this phenomenon, the model has been applied to different numerical cases. The obtained results, which are qualitatively consistent with well-known related experimental works, indicate that cell morphology not only depends on substrate stiffness but also on the substrate boundary conditions. A cell located within an unconstrained soft substrate (several kPa) with uniform stiffness is unable to adhere to its substrate or to send out pseudopodia. When the substrate stiffness increases to tens of kPa (intermediate and rigid substrates), the cell can adequately adhere to its substrate. Subsequently, as the traction forces exerted by the cell increase, the cell elongates and its shape changes. Within very stiff (hard) substrates, the cell cannot penetrate into its substrate or send out pseudopodia. On the other hand, a cell is found to be more elongated within substrates with a constrained surface. However, this elongation decreases when the cell approaches it. It can be concluded that the higher the net traction force, the greater the cell elongation, the larger the cell membrane area, and the less random the cell alignment.

Jamaleddin Mousavi, Seyed; Hamdy Doweidar, Mohamed

2014-08-01

30

Morphological classification of plant cell deaths  

PubMed Central

Programmed cell death (PCD) is an integral part of plant development and of responses to abiotic stress or pathogens. Although the morphology of plant PCD is, in some cases, well characterised and molecular mechanisms controlling plant PCD are beginning to emerge, there is still confusion about the classification of PCD in plants. Here we suggest a classification based on morphological criteria. According to this classification, the use of the term ‘apoptosis' is not justified in plants, but at least two classes of PCD can be distinguished: vacuolar cell death and necrosis. During vacuolar cell death, the cell contents are removed by a combination of autophagy-like process and release of hydrolases from collapsed lytic vacuoles. Necrosis is characterised by early rupture of the plasma membrane, shrinkage of the protoplast and absence of vacuolar cell death features. Vacuolar cell death is common during tissue and organ formation and elimination, whereas necrosis is typically found under abiotic stress. Some examples of plant PCD cannot be ascribed to either major class and are therefore classified as separate modalities. These are PCD associated with the hypersensitive response to biotrophic pathogens, which can express features of both necrosis and vacuolar cell death, PCD in starchy cereal endosperm and during self-incompatibility. The present classification is not static, but will be subject to further revision, especially when specific biochemical pathways are better defined. PMID:21494263

van Doorn, W G; Beers, E P; Dangl, J L; Franklin-Tong, V E; Gallois, P; Hara-Nishimura, I; Jones, A M; Kawai-Yamada, M; Lam, E; Mundy, J; Mur, L A J; Petersen, M; Smertenko, A; Taliansky, M; Van Breusegem, F; Wolpert, T; Woltering, E; Zhivotovsky, B; Bozhkov, P V

2011-01-01

31

Morphological study of penumbral formation  

NASA Astrophysics Data System (ADS)

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

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

2014-10-01

32

A Noninvasive Genetic\\/Pharmacologic Strategy for Visualizing Cell Morphology and Clonal Relationships in the Mouse  

Microsoft Academic Search

Analysis of cellular morphology is the most general approach to neuronal classification. With the increased use of genetically engineered mice, there is a growing need for methods that can selectively visualize the morphologies of specified subsets of neurons. This capability is needed both to define cell morphologic phenotypes and to mark cells in a noninvasive manner for lineage studies. To

Tudor C. Badea; Yanshu Wang; Jeremy Nathans

2003-01-01

33

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. PMID:7142283

1982-01-01

34

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

35

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. PMID:24872797

2014-01-01

36

Morphological effect of oscillating magnetic nanoparticles in killing tumor cells.  

PubMed

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

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

2014-01-01

37

[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

38

Morphological and Electrical Properties of Human Trophoblast Choriocarcinoma, BeWo Cells  

Microsoft Academic Search

The syncytiotrophoblast of the human placenta arises from fusion of stem cells called cytotrophoblasts. The molecular mechanisms associated with cell fusion and syncytiation of cytotrophoblastic cells remain largely unknown. In the present study, we investigated the morphological and electrical properties of BeWo cells, a human choriocarcinoma-derived trophoblast cell model, with several features of the human cytotrophoblast. Cultured cells tended to

A. J. Ramos; M. R. Cantero; P. Zhang; M. K. Raychowdhury; A. Green; D. MacPhee; H. F. Cantiello

2008-01-01

39

Heme-oxygenase-1 implications in cell morphology and the adhesive behavior of prostate cancer cells  

PubMed Central

Prostate cancer (PCa) is the second leading cause of cancer death in men. Although previous studies in PCa have focused on cell adherens junctions (AJs), key players in metastasis, they have left the molecular mechanisms unexplored. Inflammation and the involvement of reactive oxygen species (ROS) are critical in the regulation of cell adhesion and the integrity of the epithelium. Heme oxygenase-1 (HO-1) counteracts oxidative and inflammatory damage. Here, we investigated whether HO-1 is implicated in the adhesive and morphological properties of tumor cells. Genes differentially regulated by HO-1 were enriched for cell motility and adhesion biological processes. HO-1 induction, increased E-cadherin and ?-catenin levels. Immunofluorescence analyses showed a striking remodeling of E-cadherin/?-catenin based AJs under HO-1 modulation. Interestingly, the enhanced levels of E-cadherin and ?-catenin coincided with a markedly change in cell morphology. To further our analysis we sought to identify HO-1 binding proteins that might participate in the regulation of cell morphology. A proteomics approach identified Muskelin, as a novel HO-1 partner, strongly implicated in cell morphology regulation. These results define a novel role for HO-1 in modulating the architecture of cell-cell interactions, favoring a less aggressive phenotype and further supporting its anti-tumoral function in PCa. PMID:24961479

Gueron, Geraldine; Giudice, Jimena; Valacco, Pia; Paez, Alejandra; Elguero, Belen; Toscani, Martin; Jaworski, Felipe; Leskow, Federico Coluccio; Cotignola, Javier; Marti, Marcelo; Binaghi, Maria; Navone, Nora; Vazquez, Elba

2014-01-01

40

Heme-oxygenase-1 implications in cell morphology and the adhesive behavior of prostate cancer cells.  

PubMed

Prostate cancer (PCa) is the second leading cause of cancer death in men. Although previous studies in PCa have focused on cell adherens junctions (AJs), key players in metastasis, they have left the molecular mechanisms unexplored. Inflammation and the involvement of reactive oxygen species (ROS) are critical in the regulation of cell adhesion and the integrity of the epithelium. Heme oxygenase-1 (HO-1) counteracts oxidative and inflammatory damage. Here, we investigated whether HO-1 is implicated in the adhesive and morphological properties of tumor cells. Genes differentially regulated by HO-1 were enriched for cell motility and adhesion biological processes. HO-1 induction, increased E-cadherin and ?-catenin levels. Immunofluorescence analyses showed a striking remodeling of E-cadherin/ ?-catenin based AJs under HO-1 modulation. Interestingly, the enhanced levels of E-cadherin and ?-catenin coincided with a markedly change in cell morphology. To further our analysis we sought to identify HO-1 binding proteins that might participate in the regulation of cell morphology. A proteomics approach identified Muskelin, as a novel HO-1 partner, strongly implicated in cell morphology regulation. These results define a novel role for HO-1 in modulating the architecture of cell-cell interactions, favoring a less aggressive phenotype and further supporting its anti-tumoral function in PCa. PMID:24961479

Gueron, Geraldine; Giudice, Jimena; Valacco, Pia; Paez, Alejandra; Elguero, Belen; Toscani, Martin; Jaworski, Felipe; Leskow, Federico Coluccio; Cotignola, Javier; Marti, Marcelo; Binaghi, Maria; Navone, Nora; Vazquez, Elba

2014-06-30

41

Morphological studies in the Gramineæ  

Microsoft Academic Search

Summary  The structure and vascular anatomy of the spikelet in the tribe Paniceæ has been studied. The present study reveals a striking\\u000a similarity in the pattern of vascular supply to various parts of the spikelet in different species. An important feature is\\u000a that the palea bundles arise conjointly with the laterals of its lemma and not from the vascular tissue destined

Naresh Chandra

1962-01-01

42

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. PMID:24683494

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

2014-01-01

43

Morphological, histochemical and immunohistochemical studies of polar fox kidney.  

PubMed

The aim of the present study was to evaluate the morphology and intermediate filaments cytokeratin, desmin and vimentin expression in the kidneys of the polar fox (Alopex lagopus). Routine morphological, histochemical and immunohistochemical techniques of examinations of the kidneys of adult male and female polar foxes were used. We found different localizations and different levels of immunoexpression of cytokeratin in epithelia of calyxes, distal tubules and Henle's loops, and also in endothelial cells. We also noted immunolocalization and immunoexpression of vimentin in mesangial cells, interstitial tissue and distal tubules. Desmin reactivity was revealed for muscle cells of arteries and mesangial cells. Our study is the first attempt to localize cytoskeletal intermediate filaments performed on polar fox kidneys. It is worth noting that our observations concerning the distribution of vimentin in the polar fox kidney may suggest that protein as being useful as a marker of distal tubules in the polar fox kidney. PMID:22532141

Laszczy?ska, Maria; O?go, Ma?gorzata; Szymeczko, Roman; Wylot, Marcin; S?uczanowska-G??bowska, Sylwia; Piotrowska, Katarzyna; Skrzypczak, Wies?aw

2012-01-01

44

Temporal, Spatial, and Morphologic Features of Hair Cell Regeneration in  

E-print Network

Temporal, Spatial, and Morphologic Features of Hair Cell Regeneration in the Avian Basilar Papilla regeneration in chicks after a single gentamicin injection. New hair cells are first identifiable days after gentamicin, in the base, and the emergence and maturation of regenerating hair cells spreads

Rubel, Edwin

45

Effects of pulsatile flow on cultured vascular endothelial cell morphology.  

PubMed

Endothelial cells (EC) appear to adapt their morphology and function to the in vivo hemodynamic environment in which they reside. In vitro experiments indicate that similar alterations occur for cultured EC exposed to a laminar steady-state flow-induced shear stress. However, in vivo EC are exposed to a pulsatile flow environment; thus, in this investigation, the influence of pulsatile flow on cell shape and orientation and on actin microfilament localization in confluent bovine aortic endothelial cell (BAEC) monolayers was studied using a 1-Hz nonreversing sinusoidal shear stress of 40 +/- 20 dynes/cm2 (type I), 1-Hz reversing sinusoidal shear stresses of 20 +/- 40 and 10 +/- 15 dynes/cm2 (type II), and 1-Hz oscillatory shear stresses of 0 +/- 20 and 0 +/- 40 dynes/cm2 (type III). The results show that in a type I nonreversing flow, cell shape changed less rapidly, but cells took on a more elongated shape than their steady flow controls long-term. For low-amplitude type II reversing flow, BAECs changed less rapidly in shape and were always less elongated than their steady controls; however, for high amplitude reversal, BAECs did not stay attached for more than 24 hours. For type III oscillatory flows, BAEC cell shape remained polygonal as in static culture and did not exhibit actin stress fibers, such as occurred in all other flows. These results demonstrate that EC can discriminate between different types of pulsatile flow environments.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1875686

Helmlinger, G; Geiger, R V; Schreck, S; Nerem, R M

1991-05-01

46

Morphological and functional properties of rat dentate granule cells after adrenalectomy  

Microsoft Academic Search

After complete adrenalectomy, part of the granule cells in the dentate gyrus undergo apoptosis. Findings on morphological changes in non-apoptotic granule cells, though, have been equivocal. In the present study we examined the dendritic trees of dentate granule cells 7 days after adrenalectomy or sham operation, and tested the hypothesis that changes in dendritic trees have considerable consequences for ionic

J. Wossink; H. Karst; O. A. Mayboroda; M. Joels

2001-01-01

47

Effect of extract of medicinal plants on the labeling of blood elements with Technetium-99m and on the morphology of red blood cells: I--a study with Paullinia cupana.  

PubMed

Drugs can alter the labeling and the morphology of red blood cells. As Paullinia cupana is used in popular medicine, we evaluated its influence on the labeling process using technetium-99m (Tc-99m). Blood was incubated with P. cupana, stannous chloride and Tc-99m. Samples were centrifuged and plasma (P) and blood cells (BC) were separated and precipitated with trichloroacetic acid. Soluble (SF) and insoluble fractions (IF) were isolated. The morphology of the blood cells was evaluated under an optical microscope. The results showed a significant (P = 0.05) decrease in the uptake of radioactivity for the RBC (97.93 +/- 0.74 to 36.90 +/- 4.71%), in IF-P and in IF-BC due to P. cupana extract. The study of the morphology of the RBC revealed alterations in the shape of these cells. We suggest that the P. cupana effect could be explained by an inhibition of the stannous and pertechnetate ions or oxidation of the stannous ion or by damages in the plasma membrane. PMID:12234573

de Oliveira, J F; Avila, A S; Braga, A C S; de Oliveira, M B N; Boasquevisque, E M; Jales, R L; Cardoso, V N; Bernardo-Filho, M

2002-07-01

48

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

PubMed Central

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

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

2012-01-01

49

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. PMID:23761740

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

2013-01-01

50

AUR1, a novel gene conferring aureobasidin resistance on Saccharomyces cerevisiae: a study of defective morphologies in Aur1p-depleted cells.  

PubMed

Aureobasidin A (AbA), a cyclic depsipeptide produced by Aureobasidium pullulans R106, is highly toxic to fungi including Saccharomyces cerevisiae. We isolated several dominant mutants of S. cerevisiae which are resistant to more than 25 micrograms/ml of AbA. From a genomic library of one such AUR1 mutant, the AUR1R (for aureobasidin resistant) mutant gene was isolated as a gene that confers resistance to AbA on wild-type cells. Its nucleotide sequence showed that the predicted polypeptide is a hydrophobic protein composed of 401 amino acids, which contains several possible transmembrane domains and at least one predicted N-linked glycosylation site. Comparison of the mutant gene with the wild-type aur1+ gene revealed that the substitution of Phe at position 158 by Tyr is responsible for acquisition of AbA resistance. We suggest that the gene product of the wild-type aur1+ is a target for AbA on the basis of following results. Firstly, cells that overexpress the wild-type aur1+ gene become resistant to AbA, just as cells with an AUR1R mutation do. Secondly, disruption of the aur1+ gene demonstrated that it is essential for growth. Thirdly, in the cells with a disrupted aur1 locus, pleiotropic morphological changes including disappearance of microtubules, degradation of tubulin and abnormal deposition of chitin were observed. Some of these abnormalities are also observed when wild-type cells are treated with AbA. The abnormality in microtubules suggests that the Aur1 protein is involved in microtubule organization and stabilization. PMID:8668135

Hashida-Okado, T; Ogawa, A; Endo, M; Yasumoto, R; Takesako, K; Kato, I

1996-05-23

51

Effects of Morphology vs. Cell-Cell Interactions on Endothelial Cell Stiffness  

PubMed Central

Biological processes such as atherogenesis, wound healing, cancer cell metastasis, and immune cell transmigration rely on a delicate balance between Cell–Cell and cell–substrate adhesion. Cell mechanics have been shown to depend on substrate factors such as stiffness and ligand presentation, while the effects of Cell–Cell interactions on the mechanical properties of cells has received little attention. Here, we use atomic force microscopy to measure the Young’s modulus of live human umbilical vein endothelial cells (HUVECs). In varying the degree of Cell–Cell contact in HUVECs (single cells, groups, and monolayers), we observe that increased cell stiffness correlates with an increase in cell area. Further, we observe that HUVECs stiffen as they spread onto a glass substrate. When we weaken Cell–Cell junctions (i.e., through a low dose of cytochalasin B or treatment with a VE-cadherin antibody), we observe that cell–substrate adhesion increases, as measured by focal adhesion size and density, and the stiffness of cells within the monolayer approaches that of single cells. Our results suggest that while morphology can roughly be used to predict cell stiffness, Cell–Cell interactions may play a significant role in determining the mechanical properties of individual cells in tissues by careful maintenance of cell tension homeostasis. PMID:21359128

Stroka, Kimberly M.; Aranda-Espinoza, Helim

2011-01-01

52

Rheumatoid synovial cells from intact joints. Morphology, growth, and polykaryocytosis.  

PubMed Central

Synovial cell lines were isolated by instillation of trypsin or chymotrypsin into intact knee joints of patients with persistent rheumatoid effusions resistant to conventional therapy. Morphology and growth in the primary phase were compared with rheumatoid cells isolated from excised synovium and nonrheumatoid synovial cells obtained from intact joints of cadavers or amputated limbs. Cell populations from all sources included varying proportions of macrophage-like and fibroblast-like cells, with only 1-3% multinucleated cells. In medium supplemented with calf serum alone, rheumatoid cells from intact joints showed negligible changes in morphology. However, in the presence of nonrheumatoid, autologous rheumatoid or homologous rheumatoid serum a rapid increase occurred in size of the macrophage-like cells and numbers of polykaryocytes, including some giant syncytial cells. These effects were directly proportional to serum concentration and were identical in fresh or heat-inactivated serum. In most of these rheumatoid cell lines no multiplication occurred, regardless of serum type or concentration. In rheumatoid synovial cells from excised synovium, human serum induced both polykaryocytosis and rapid growth of fibroblasts. Nonrheumatoid synovial cells grew rapidly but few polykaryocytes developed, mostly with less than 6 nuclei. Evidence of viral infection in rheumatoid synovial cells was sought by electron microscopy after stimulation of polykaryocytosis by human serum. In one of the cultures many cells were found with intranuclear particles possessing characteristics of the adenovirus group. Images PMID:901027

Clarris, B J; Fraser, J R; Moran, C J; Muirden, K D

1977-01-01

53

Developmental Cell A Morphologically Conserved Nonapoptotic  

E-print Network

. Similar features are seen during developmental death of neurons in the vertebrate spinal cord and cil. For example, the normal death of motor neurons in the mouse spinal cord is independent of either caspase-3, and a reduced capacity for cell death is thought to be essential for the development of most, if not all, tumors

Shaham, Shai

54

The relationship of red cell membrane lipid content to red cell morphology and survival in patients with liver disease.  

PubMed

The relationship of red blood cell (RBC) membrane lipid content to RBC morphology and survival was studied in patients with liver diseases. An increase in RBC cholesterol and phospholipid was detected in most patients with hepatocellular disease or cholestatic jaundice but the alteration in RBC lipid content did not correlate with RBC survival. The main abnormality of RBC morphology observed was the presence of macrocytes and target cells. In a small proportion of patients (approximately 3%) with severe hepatocellular disease, significant numbers of severely deformed ("spur") cells were seen. In these patients haemolysis was moderately severe and the RBC lipid profile showed increased membrane cholesterol without a concomitant increase in phospholipids. It is concluded that only in patients with "spur" cell anaemia do the morphological alterations lead to premature removal of cells from the circulation. The cause of the shortened RBC survival in jaundiced patients without "spur" cells remains to be determined. PMID:1057918

Powell, L W; Halliday, J W; Knowles, B R

1975-04-01

55

Physiological and morphological development of the rat cerebellar Purkinje cell.  

PubMed

Cerebellar Purkinje cells integrate multimodal afferent inputs and, as the only projection neurones of the cerebellar cortex, are key to the coordination of a variety of motor- and learning-related behaviours. In the neonatal rat the cerebellum is undeveloped, but over the first few postnatal weeks both the structure of the cerebellum and cerebellar-dependent behaviours mature rapidly. Maturation of Purkinje cell physiology is expected to contribute significantly to the development of cerebellar output. However, the ontogeny of the electrophysiological properties of the Purkinje cell and its relationship to maturation of cell morphology is incompletely understood. To address this problem we performed a detailed in vitro electrophysiological analysis of the spontaneous and intracellularly evoked intrinsic properties of Purkinje cells obtained from postnatal rats (P0 to P90) using whole-cell patch clamp recordings. Cells were filled with neurobiotin to enable subsequent morphological comparisons. Three stages of physiological and structural development were identified. During the early postnatal period (P0 to approximately P9) Purkinje cells were characterized by an immature pattern of Na(+)-spike discharge, and possessed only short multipolar dendrites. This was followed by a period of rapid maturation (from approximately P12 to approximately P18), consisting of changes in Na(+)-spike discharge, emergence of repetitive bursts of Na(+) spikes terminated by Ca(2+) spikes (Ca(2+)-Na(+) bursts), generation of the trimodal pattern, and a significant expansion of the dendritic tree. During the final stage (> P18 to P90) there were minor refinements of cell output and a plateau in dendritic area. Our results reveal a rapid transition of the Purkinje cell from morphological and physiological immaturity to adult characteristics over a short developmental window, with a close correspondence between changes in cell output and dendritic growth. The development of Purkinje cell intrinsic electrophysiological properties further matches the time course of other measures of cerebellar structural and functional maturation. PMID:16002452

McKay, Bruce E; Turner, Ray W

2005-09-15

56

Unraveling the Role of Morphology on Organic Solar Cell Performance  

E-print Network

Polymer based organic photovoltaic (OPV) technology offers a relatively inexpensive option for solar energy conversion provided its efficiency increases beyond the current level (6-7%) along with significant improvements in operational lifetime. The critical aspect of such solar cells is the complex morphology of distributed bulk heterojunctions, which plays the central role in the conversion of photo-generated excitons to electron-hole pairs. However, the fabrication conditions that can produce the optimal morphology are still unknown due to the lack of quantitative understanding of the effects of process variables on the cell morphology. In this article, we develop a unique process-device co-simulation framework based on phase-field model for phase separation coupled with self-consistent drift-diffusion transport to quantitatively explore the effects of the process conditions (e.g., annealing temperature, mixing ratio, anneal duration) on the organic solar cell performance. Our results explain experimentally observed trends of open circuit voltage and short circuit current that would otherwise be deemed anomalous from the perspective of conventional solar cells. In addition to providing an optimization framework for OPV technology, our morphology-aware modeling approach is ideally suited for a wide class of problems involving porous materials, block co-polymers, polymer colloids, OLED devices etc.

Biswajit Ray; Pradeep R. Nair; Muhammad A. Alam

2010-11-03

57

Morphologic, Phenotypic and Functional Characteristics of Endothelial Cells Derived from Human Hepatic Cavernous Hemangioma  

Microsoft Academic Search

Backgrounds\\/Aims: The pathogenesis of cavernous hemangiomas is largely unknown, and it is speculated that abnormal vasculogenesis and angiogenesis may be involved. In this study, the characteristics of cavernous hemangioma endothelial cells (CHECs) derived from the human liver were analyzed in terms of morphology, phenotype and function and compared with human liver sinusoidal endothelial cells (LSECs). Methods and Results: By transmission

Wen-jian Zhang; Li-ya Ye; Lian-qiu Wu; Yu-ling Xin; Feng Gu; Ji-xiao Niu; Zhi-hua Yang; Guang-jin Zhu; Georges E. Grau; Jin-ning Lou

2006-01-01

58

Effect of substratum on growth, cell morphology and lactoferrin synthesis and secretion in bovine mammary cell culture  

Microsoft Academic Search

The role of extracellular matrix in morphology, growth and lactoferrin synthesis and secretion in bovine mammary cells from a developing gland is poorly defined. In this study, bovine mammary cells from a hormone-primed developing gland were isolated and cultured on plastic, collagen, embedded within collagen, or on EHS-matrix, with the hormones prolactin, insulin, and cortisol in the presence or absence

R. S. Talhouk; R. L. Neiswander; F. L. Schanbacher

1998-01-01

59

Dynamic and reversible surface topography influences cell morphology.  

PubMed

Microscale and nanoscale surface topography changes can influence cell functions, including morphology. Although in vitro responses to static topography are novel, cells in vivo constantly remodel topography. To better understand how cells respond to changes in topography over time, we developed a soft polyacrylamide hydrogel with magnetic nickel microwires randomly oriented in the surface of the material. Varying the magnetic field around the microwires reversibly induced their alignment with the direction of the field, causing the smooth hydrogel surface to develop small wrinkles; changes in surface roughness, ?RRMS , ranged from 0.05 to 0.70 ?m and could be oscillated without hydrogel creep. Vascular smooth muscle cell morphology was assessed when exposed to acute and dynamic topography changes. Area and shape changes occurred when an acute topographical change was imposed for substrates exceeding roughness of 0.2 ?m, but longer-term oscillating topography did not produce significant changes in morphology irrespective of wire stiffness. These data imply that cells may be able to use topography changes to transmit signals as they respond immediately to changes in roughness. PMID:23355509

Kiang, Jennifer D; Wen, Jessica H; del Álamo, Juan C; Engler, Adam J

2013-08-01

60

Organic solar cells: an overview focusing on active layer morphology.  

PubMed

Solar cells constructed of organic materials are becoming increasingly efficient due to the discovery of the bulk heterojunction concept. This review provides an overview of organic solar cells. Topics covered include: a brief history of organic solar cell development; device construction, definitions, and characteristics; and heterojunction morphology and its relation to device efficiency in conjugated polymer/fullerene systems. The aim of this article is to show that researchers are developing a better understanding of how material structure relates to function and that they are applying this knowledge to build more efficient light-harvesting devices. PMID:16408145

Benanti, Travis L; Venkataraman, D

2006-01-01

61

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

Microsoft Academic Search

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

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

2011-01-01

62

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

NASA Astrophysics Data System (ADS)

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

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

2014-01-01

63

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. PMID:23308209

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

2013-01-01

64

[Experimental-morphological study of the roentgeno-endovascular prosthesis].  

PubMed

The authors presented the results of experimental studies on 36 dogs: 66 endovascular spiral wire prostheses made of a metal alloy with a shape "memory" effect were implanted in the aorta and major arteries via an angiographic catheter. Long-term results were followed-up over a period of 14 mos. and demonstrated a good and prolonged permeability of the nitinol prostheses. Morphological investigations showed that the endovascular prosthesis was separated in a ring-like fashion by a thin layer of connective tissue and from within it was lined with a layer of epithelial cells. PMID:3773664

Rabkin, D I; Minkina, S M; Kadnikov, A A; Khasenov, B P

1986-10-01

65

Cell Sorting Enriches Escherichia coli Mutants That Rely on Peptidoglycan Endopeptidases To Suppress Highly Aberrant Morphologies  

PubMed Central

Bacterial morphology imparts physiological advantages to cells in different environments and, judging by the fidelity with which shape is passed to daughter cells, is a tightly regulated characteristic. Surprisingly, only in the past 10 to 15 years has significant headway been made in identifying the mechanisms by which cells create and maintain particular shapes. One reason for this is that the relevant discoveries have relied heavily on the arduous, somewhat subjective process of manual microscopy. Here, we show that flow cytometry, coupled with the sorting capability of fluorescence-activated cell sorting (FACS), can detect, quantify, and enrich bacteria with morphological alterations. The light scattering properties of several highly aberrant morphological mutants of Escherichia coli were characterized by flow cytometry. Cells from a region that overlapped the distribution of normal rod-shaped cells were collected by FACS and reincubated. After 4 to 15 iterations of this enrichment process, suppressor mutants were isolated that returned almost all the population to a near-normal shape. Suppressors were successfully isolated from strains lacking three or four penicillin binding proteins (PBPs) but not from a mutant lacking a total of seven PBPs. The peptidoglycan endopeptidase, AmpH, was identified as being important for the suppression process, as was a related endopeptidase, MepA. The results validate the use of cell sorting as a means for studying bacterial morphology and identify at least one new class of enzymes required for the suppression of cell shape defects. PMID:23243305

Laubacher, Mary E.; Melquist, Amy L.; Chandramohan, Lakshmi

2013-01-01

66

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

Microsoft Academic Search

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

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

2011-01-01

67

The Anterior Olfactory Nucleus: Quantitative Study of Dendritic Morphology  

PubMed Central

The anterior olfactory nucleus (AON) occupies a crucial position within the olfactory circuit as it is able to influence function in nearly every major synaptic processing stage of both the ipsilateral and contralateral pathway. Nevertheless, very little is known about the region’s internal organization and circuitry. The present study provides basic quantitative and qualitative data on the morphology of several cell types within the two major regions of the AON: pars externa and pars principalis. In pars externa two types of cells are analyzed, the “classical” cell (Type I), containing only apically-directed dendrites with large spines, and a previously unreported cell with basilar dendrites and complex, spiny apical processes (Type II). In pars principalis the characteristic pyramidal cell is described both on the basis of the depth of the cell bodies in the cell layer comprising the structure and on the basis of their radial location. Several other non-pyramidal neurons are also described. The findings provide useful basic information necessary for understanding and modeling the circuitry of the AON. PMID:20187150

Brunjes, Peter C.; Kenerson, Michael C.

2012-01-01

68

Bovine oviductal epithelial cells: Long term culture characterization and impact of insulin on cell morphology.  

PubMed

In vitro models that resemble cell function in vivo are needed to understand oviduct physiology. This study aimed to assess cell functions and insulin effects on bovine oviductal epithelial cells (BOECs) cultured in an air-liquid interface. BOECs (n=6) were grown in conditioned Ham's F12, DMEM or Ham's F12/DMEM with 10% fetal calf serum (FCS) for 3 weeks. After selecting the most suitable medium (Ham's F12), increasing insulin concentrations (1ng/mL, 20ng/mL and 5?g/mL) were applied, and cell morphology and trans-epithelial electrical resistance (TEER; n=4) were evaluated after 3 and 6 weeks. Keratin immunohistochemistry and mRNA expression of oviductal glycoprotein 1 (OVGP1) and progesterone receptor (PGR) were conducted (n=4) to assess cell differentiation. BOECs grown without insulin supplementation or with 1ng/mL of insulin displayed polarization and secretory activity. However, cells exhibited only 50% of the height of their in vivo counterparts. Cultures supplemented with 20ng/mL insulin showed the highest quality, but the 5?g/mL concentration induced massive growth. TEER correlated negatively with insulin concentration (r=-0.459; p=0.009). OVGP1 and PGR transcripts were still detectable after 3 and 6 weeks. Cellular localization of keratins closely resembled that of BOECs in vivo. Cultures showed heterogeneous expression of PGR and OVGP1 in response to estradiol (10pg/mL). In summary, BOECs grown for long term in an air-liquid interface expressed markers of cell differentiation. Additionally, insulin supplementation (20ng/mL) improved the cell morphology in vitro. PMID:25152518

Palma-Vera, S; Einspanier, R; Schoen, J

2014-09-01

69

Inhibition of the effects of rheumatoid synovial fluid cells on chondrogenesis and cartilage breakdown in vitro: possible therapeutical conclusions. A morphological--biochemical study.  

PubMed

Short-term co-cultivation of blastemal cells from 12-day-old mouse limb buds and human rheumatoid synovial fluid cells in high density cultures (Trowell culture system) resulted, depending on when co-cultivation started, either in (1) an inhibition of chondrogenesis (co-cultivation right from the start) or in (2) an extensive breakdown of cartilaginous matrix (co-cultivation after formation of embryonic cartilage). These synovial effects were markedly impeded if Avarol (a dioxygenase inhibitor) was applied singly or in combination with PAI-2 (a u-PA-inhibitor). PAI-2 alone, however, had no effect on the synovial-induced inhibition of chondrogenesis, but produced a pronounced inhibitory effect on matrix breakdown. The effects of both inhibitors were studied electron microscopically and biochemically (determination of sulfated-glycosaminoglycans in the high density cultures by Alcian Blue binding assay). The results of this study are consistent with the presumption that rheumatoid synovial cells are capable of inhibiting chondrogenesis and enhancing the breakdown of the cartilaginous matrix. Amongst others, the possible mediators involved are prostaglandins and plasminogen activators. The response to the inhibitors Avarol and PAI-2 is compatible with their mode of action. The chondroprotective action of these substances may be useful in developing potential antirheumatic drugs. PMID:8401816

Mohamed-Ali, H; Scholz, P; Merker, H J

1993-01-01

70

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

71

Morphology matters in immune cell chemotaxis: membrane asymmetry affects amplification  

NASA Astrophysics Data System (ADS)

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

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

2006-09-01

72

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

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

73

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

PubMed Central

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

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

2013-01-01

74

Morphological and electrophysiological properties of pelvic ganglion cells in the rat.  

PubMed

Intracellular recording and dye injection were used to study the morphological and electrophysiological properties of rat pelvic ganglion cells. The dye-injected cells measured on the average 37 micron by 22.5 micron and had a mean number of 1.5 primary processes (axon and dendrites). The cells received unmyelinated preganglionic inputs from either the pelvic (parasympathetic) or the hypogastric (sympathetic) nerves, but no cells received inputs from both nerves. The number of synaptic inputs to each cell varied between 1 and 5 with a mean of 2. Each cell had at least one large amplitude suprathreshold EPSP which always initiated an action potential. These properties, namely, morphological simplicity, small number of inputs, security of synaptic transmission and lack of convergence between sympathetic and parasympathetic inputs, suggest that the capacity for synaptic modulation and integration in this ganglion is minimal. Such a structure should therefore relay preganglionic information to target organs with little or no alteration. PMID:3768682

Tabatai, M; Booth, A M; de Groat, W C

1986-09-10

75

Red blood cell morphology in sickle cell anemia as determined by image processing analysis: the relationship to painful crises.  

PubMed

Red blood cell morphology was studied in the peripheral blood of adults with sickle cell anemia to determine if changes occur during painful crises. Image processing of the cells with an automated system of red blood cell analysis was used. Four groups of cells were observed: normocytes, macrocytes, target cells, and cells with the shape of irreversibly sickled cells. During asymptomatic periods, the percentages of these cells differed in each individual but were typical for that individual and generally were stable. During crises, macrocytosis occurred and the concentration of irreversibly sickled cells showed greater fluctuation. The macrocytosis most likely reflected a marrow response to increased hemolysis and demonstrated that the increased red blood cell destruction observed during pain crises may be more extensive than previously considered. Changes in the concentration of irreversibly sickled cells during crises were not consistent and could not be used as an indicator of a crisis. Image processing with automated red blood cell analysis allows for accurate assessment of all the morphologic groups of red blood cells in patients with sickle cell anemia and compares well with standard methods for measuring the concentration of irreversibly sickled cells. PMID:6846257

Westerman, M P; Bacus, J W

1983-06-01

76

Morphologic and immunophenotypic properties of neoplastic cells in a case of mast cell sarcoma.  

PubMed

Mast cell sarcoma is an extremely rare and aggressive type of mast cell disease. Only a few cases have been described so far, and little is known about the biology and phenotype of afflicted cells. We describe morphologic and immunophenotypic properties of neoplastic mast cells in a case of an intracranial mast cell sarcoma. In Wright-Giemsa-stained cytospin preparations, the morphology of dispersed cells appeared to be highly atypical with a considerable percentage of metachromatic blasts and mast cells with bilobed or multilobed nuclei. Combined toluidine blue/immunofluorescence staining revealed expression of CD13, CD45, CD88, CD116, and CD117 (c-KIT) on neoplastic mast cells. As assessed by immunohistochemistry, mast cells were immunoreactive for tryptase and CD68R, In contrast, the CD2 antigen that is expressed in mast cells in patients with indolent systemic mastocytosis was not detectable. Mast cells also failed to display the c-KIT mutation Asp-816-Val, which is typically found in systemic mast cell disorders. Together, neoplastic mast cells in a case of mast cell sarcoma were found to exhibit unique morphologic, phenotypical, and molecular features when compared with mast cells in indolent mastocytosis or normal tissue mast cells. PMID:12826896

Chott, Andreas; Guenther, Philipp; Huebner, Angela; Selzer, Edgar; Parwaresch, Reza M; Horny, Hans-Peter; Valent, Peter

2003-07-01

77

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

PubMed

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

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

2007-06-13

78

Morphological, pharmacokinetic, and hematological studies of lead-exposed pigeons  

SciTech Connect

Adult white Carneaux pigeons were orally dosed with inorganic lead (6.25 mg Pb/kg/day, gastric intubation) for up to 64 weeks and the following studies were carried out: (1) the subcellular distribution of lead in erythrocytes; (2) the changes in tissue lead levels with time; (3) morphological assessment of tissue responses to lead; and (4) hematological effects of lead, the major systemic evidence of toxicity. In the early stage of exposure, there is some lead accumulation in the erythrocyte nucleus relative to its proportion of total cell volume, but such accumulation disappears with time. The kinetic behavior of lead in seven tissues--blood, brain, kidney, liver, femur, sciatic nerve, and crop--was seen to conform to two mathematical methods of lead distribution; brain, kidney, and femur lead increased with dosing time and reached or appeared to approach an upper plateau; lead in blood, liver, sciatic nerve, and crop increased to a maximum, followed by a decline to a lower plateau level. Morphologically, renal tubule cells showed the presence of lead-containing inclusion bodies while CNS mitochondria appeared to have accumulated lead. No evidence of segmental demyelination was seen. Lead exposure induced a marked and rapid hypochromic normocytic anemia in these birds, as well as an elevation in erythrocyte porphyrin. No disturbance in mechanical fragility or osmotic resistance was noted.

Anders, E. (Univ. of North Carolina, Chapel Hill); Dietz, D.D.; Bagnell, C.R. Jr.; Gaynor, J.; Krigman, M.R.; Ross, D.W.; Leander, J.D.; Mushak, P.

1982-08-01

79

Comparative compositional analysis of walls with two different morphologies: archetypical versus transfer-cell-like  

Microsoft Academic Search

Summary Abnormally thick cell walls of a clonal maize cell line with the labyrinth wall morphology found in transfer cells were analyzed and compared to the relatively thin and even archetypical walls of a sister cell line. Despite a drastic difference in wall morphology between the transfer and archetypical cell walls, the chemical composition of the walls was essentially the

Greg DeWitt; Jason Richards; Debra Mohnen; Alan M. Jones

1999-01-01

80

Enhancement of the morphological transformation of Syrian hamster embryo (SHE) cells by reducing incubation time of the target cells.  

PubMed

Syrian hamster embryo (SHE) cell transformation has been used for many years to study chemical carcinogenesis in vitro. It has been shown that this assay is probably the most predictive short-term test system for identifying rodent carcinogens. Although most of the operational difficulties encountered in the early stage of application of this assay have been overcome by culturing the SHE cells under slightly acidic conditions (pH 6.7), a relatively low level of induction of morphological transformation (MT) by known carcinogens still occurs for many cell isolates. In order to improve the response of this assay system to known carcinogens, the effect of incubation time of target SHE cells on the frequency of morphological transformation induced by benzo(a)pyrene (BaP) was investigated. It was shown that the morphological transformation frequency induced by BaP increased significantly (1.4-2.5-fold) when the incubation time of target cells was reduced from the usual 24h to less than 6h prior to seeding onto feeder layers. This improvement in sensitivity was consistent for different cell isolates. In addition, the enhanced response appeared to be a property of carcinogens because treatment with two non-carcinogens, l-ascorbic acid and 4-nitro-o-phenylenediamine, did not induce significant increases in the transformation frequency under the shortened incubation period for target cells. These results suggest that the response of the SHE cell transformation assay may be improved by optimizing the incubation time of the target SHE cells. In addition, the results of the present study provide further evidence to support the idea that morphological transformation of SHE cells results from a block of cellular differentiation of stem or stem-like cells. PMID:15063130

Zhang, H; Borman, H D; Myhr, B C

2004-04-14

81

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

PubMed

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

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

2014-07-01

82

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

83

WR-1065 and radioprotection of vascular endothelial cells. II. Morphology  

SciTech Connect

Although the aminothiol WR-1065 protects normal tissues, its direct effect on the damage and restoration of the vascular endothelium is not clear. In endothelial cells, WR-1065 attenuates both the DNA damage and the G{sub 1}-phase arrest induced by radiation. After the destruction of nearby endothelial cells, the survivors rearrange their cytoskeleton, migrate and replicate. To determine the effect of radiation on morphology and migration, portions of bovine aortic endothelial cell cultures were denuded with a pipette tip and irradiated ({sup 137}Cs {gamma} rays). The following observations were noted after 5 Gy: within 10 min, there was increased formation of protein-mixed disulfides including actin-mixed disulfide; after 30 min, {alpha}{sub 5}{Beta}{sub 1}, the integrin receptor for fibronectin, was up-regulated on the apical membrane surface. Within 5 h, actin-containing stress fibers reorganized, although there was no change in the total filamentous (F-)actin content within the cells. Compared to controls after 24 h, the irradiated cells had migrated 15% farther (P < 0.01), and at the leading edge covered twice the surface area (P < 0.0001). The addition of 2 mM WR-1065 for 2 h before 5 Gy inhibited the increased expression of {alpha}{sub 5}{Beta}{sub 1}, promoted retention of stress fibers and prevented the enhanced cell migration and spreading. These results indicate that WR-1065 prevents radiation-induced morphological responses. This effect appears to be mediated by an impact on both adhesion molecule expression and cytoskeletal reorganization. 61 refs., 6 figs.

Mooteri, S.N.; Podolski, J.L.; Drab, E.A.; Saclarides, T.J. [Rush Medical College, Chicago, IL (United States)] [and others

1996-02-01

84

Inhibitory effects of phenylbutyrate on the proliferation, morphology, migration and invasiveness of malignant glioma cells  

Microsoft Academic Search

The purpose of this study was to characterize the effects of sodium 4-phenylbutyrate (phenylbutyrate) on the proliferation, morphology, migration and invasiveness of malignant glioma cells in vitro. Phenylbutyrate is a novel differentiating and cytotoxic compound used clinically with low toxicity in the treatment of ß-thalassemia, sickle cell anemia and urea cycle disorders. Preliminary clinical trials testing phenylbutyrate as an anti-cancer

Herbert H. Engelhard; Ronald J. Homer; Holly A. Duncan; Jack Rozental

1998-01-01

85

[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

86

Mitochondrial morphology transition is an early indicator of subsequent cell death in Arabidopsis.  

PubMed

Mitochondrial morphology and dynamics were investigated during the onset of cell death in Arabidopsis thaliana. Cell death was induced by either chemical (reactive oxygen species (ROS)) or physical (heat) shock. Changes in mitochondrial morphology in leaf tissue, or isolated protoplasts, each expressing mitochondrial-targeted green fluorescent protein (GFP), were observed by epifluorescence microscopy, and quantified. Chemical induction of ROS production, or a mild heat shock, caused a rapid and consistent change in mitochondrial morphology (termed the mitochondrial morphology transition) that preceded cell death. Treatment of protoplasts with a cell-permeable superoxide dismutase analogue, TEMPOL, blocked this morphology change. Incubation of protoplasts in micromolar concentrations of the calcium channel-blocker lanthanum chloride, or the permeability transition pore inhibitor cyclosporin A, prevented both the mitochondrial morphology transition and subsequent cell death. It is concluded that the observed mitochondrial morphology transition is an early and specific indicator of cell death and is a necessary component of the cell death process. PMID:17986180

Scott, Iain; Logan, David C

2008-01-01

87

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

88

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. PMID:20350691

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

2010-01-01

89

Regulation of cerebral endothelial cell morphology by extracellular calcium  

NASA Astrophysics Data System (ADS)

Cerebral endothelial cells interconnected by tight and adherens junctions constitute the structural basis of the blood-brain barrier. Extracellular calcium ions have been reported to play an important role in the formation and maintenance of the junctional complex. However, little is known about the action of calcium depletion on the structural characteristics of cerebral endothelial cells. Using atomic force microscopy we analyzed the effect of calcium depletion and readdition on the shape and size of living brain endothelial cells. It was found that the removal of extracellular calcium from confluent cell cultures induced the dissociation of the cells from each other accompanied by an increase in their height. After readdition of calcium a gradual recovery was observed until total confluency was regained. We have also demonstrated that Rho-kinase plays an important role in the calcium-depletion-induced disassembly of endothelial tight and adherens junctions. The Rho-kinase inhibitor Y27632 could prevent the morphological changes induced by a lack of calcium as well. Our results suggest that calcium depletion induces Rho-kinase-dependent cytoskeletal changes that may be partly responsible for the disassembly of the junctional complex.

Wilhelm, Imola; Farkas, Attila E.; Nagyoszi, Péter; Váró, György; Bálint, Zoltán; Végh, Gergely A.; Couraud, Pierre-Olivier; Romero, Ignacio A.; Weksler, Babette; Krizbai, István A.

2007-10-01

90

Regulation of cerebral endothelial cell morphology by extracellular calcium.  

PubMed

Cerebral endothelial cells interconnected by tight and adherens junctions constitute the structural basis of the blood-brain barrier. Extracellular calcium ions have been reported to play an important role in the formation and maintenance of the junctional complex. However, little is known about the action of calcium depletion on the structural characteristics of cerebral endothelial cells. Using atomic force microscopy we analyzed the effect of calcium depletion and readdition on the shape and size of living brain endothelial cells. It was found that the removal of extracellular calcium from confluent cell cultures induced the dissociation of the cells from each other accompanied by an increase in their height. After readdition of calcium a gradual recovery was observed until total confluency was regained. We have also demonstrated that Rho-kinase plays an important role in the calcium-depletion-induced disassembly of endothelial tight and adherens junctions. The Rho-kinase inhibitor Y27632 could prevent the morphological changes induced by a lack of calcium as well. Our results suggest that calcium depletion induces Rho-kinase-dependent cytoskeletal changes that may be partly responsible for the disassembly of the junctional complex. PMID:17921584

Wilhelm, Imola; Farkas, Attila E; Nagyoszi, Péter; Váró, György; Bálint, Zoltán; Végh, Gergely A; Couraud, Pierre-Olivier; Romero, Ignacio A; Weksler, Babette; Krizbai, István A

2007-10-21

91

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

PubMed Central

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

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

2012-01-01

92

A subset of morphologically distinct mammary myoepithelial cells lacks corresponding immunophenotypic markers  

PubMed Central

Introduction Immunostaining for smooth muscle actin (SMA) is commonly used to elucidate mammary myoepithelial (ME) cells, whose presence or absence is a reliable criterion for differentiating in situ and invasive carcinomas. However, some morphologically distinct ME cells fail to stain for SMA. This study intended to assess whether these SMA-negative cells also lack the expression of other ME cell markers. Methods Hematoxylin/eosin and SMA immunostained sections from 175 breast cancer patients were examined. Three cases were found to harbor ducts that showed morphologically distinct ME cell layers, but showed no SMA immunostaining in at least one-third of the layer or the entire layer. Eight additional consecutive sections from each case were stained for SMA, using a black chromogen, and each was then re-stained for one of eight additional markers supposed to exclusively or preferentially stain ME cells, using a red chromogen. SMA-negative ME cells were re-examined for the expression of other markers. Results SMA-negative ME cells in two cases also failed to display immunoreactivity for other markers, including calponin, CD10, smooth muscle myosin heavy chain, protease inhibitor 5 (maspin), Wilms' tumor-1, and cytokeratins 5, 14, and 17 (CK5, CK14, and CK17). However, in one case SMA-negative ME cells displayed immunoreactivities for maspin, CK5, CK14, and CK17. The distribution of these ME cells is independent of ductal size, length, and architecture. Conclusions A subset of morphologically identifiable ME cells lack the expression of nine corresponding immunophenotypic markers, suggesting that ME cells might also be subject to different normal and pathological alterations. PMID:12927046

Zhang, Roy R; Man, Yan-Gao; Vang, Russell; Saenger, Jeffrey S; Barner, Ross; Wheeler, Darren T; Liang, Chang Y; Vinh, Tuyethoa N; Bratthauer, Gary L

2003-01-01

93

Computational study of actin morphology and rheology  

E-print Network

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

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

2011-01-01

94

Morphological, Biological, and Biochemical Characteristics of Human Bladder Transitional Cell Carcinomas Grown in Tissue Culture and in Nude Mice1  

Microsoft Academic Search

The morphological, biological, biochemical, and karyotypic characteristics of four human bladder transitional cell carcinoma lines, SW-780, SW-800, SW-1738, and SW-1710, were investi gated. In tissue culture, each cell line presented a distinct phen- otypic expression. All but line SW-1710 grew when transplanted in the nude mouse. Light and electron microscopic studies showed morphological characteristics similar to the tumors of origin,

Aikaterini A. Kyriazis; Andreas P. Kyriazis; William B. McCombs; Ward D. Peterson

95

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

96

Studying femtosecond-laser hyperdoping by controlling surface morphology  

E-print Network

We study the fundamental properties of femtosecond-laser (fs-laser) hyperdoping by developing techniques to control the surface morphology following laser irradiation. By decoupling the formation of surface roughness from ...

Winkler, Mark T.

97

Morphological and ultrastructural study of extrusion texturized defatted soy flour  

E-print Network

MORPHOLOGICAL AND ULTRASTRUCTURAL STUDY OF EXTRUSION TEXTURIZED DEFATTED SOY FLOUR A Thesis by MASSOUD KAZEMZADEH Submitted to the Graduate College of Texas A&% University in partial fulfillment of the requirement for the degree of MASTER... OF SCIEiVCE May 1980 Major Subject: Food Science and Technology MORPHOLOGICAL AHD ULTRASTRUCTURAL STUDY OF EXTRUSION TEXTURIZED DEFATTED SOY FLOUR A Thesis by MASSOUD KAZEMZADEH Approved as to style and content by: (Chairman oi' ommittee) (Member...

Kazemzadeh, Massoud

2012-06-07

98

Maintenance of the Cell Morphology by MinC in Helicobacter pylori  

PubMed Central

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

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

2013-01-01

99

Expression of HGF/SF in mesothelioma cell lines and its effects on cell motility, proliferation and morphology.  

PubMed Central

The expression of hepatocyte growth factor/scatter factor (HGF/SF) was studied in 12 mesothelioma cell lines characterized by either an epithelioid or a fibroblast-like phenotype. Conditioned media from these lines were analysed by bioassay and ELISA, and HGF/SF was detected in three cell lines, all with a fibroblast-like or mixed morphology. None of eight epithelioid cell lines expressed the factor. Thus, for these cell lines, the ability to secrete HGF/SF correlated with the cell phenotype. Following on from these observations, two cell lines, BR and BT, with a fibroblast-like and an epithelioid phenotype, respectively, were further investigated. Both cell lines expressed the Met receptor but only BR secreted HGF/SF. Both cell lines responded to exogenous HGF/SF treatment by a change of morphology but in different ways: BR became more elongated and bipolar, while BT formed more spread-out cell colonies. HGF/SF acted as a paracrine effector on the epithelioid BT cells and stimulated both cell-spreading and proliferation. Interestingly, BT cells spread but did not scatter in response to exogenous HGF/SF. In contrast BR cells showed only some stimulation of cell motility with HGF/SF and no increase in cell proliferation was observed. Because HGF/SF was previously found in the pleural effusion fluids of patients with malignant mesothelioma and in paraffin-embedded tumour tissues, it is concluded that HGF/SF may well stimulate the growth and spread of malignant mesothelioma in vivo by paracrine and/or autocrine mechanisms. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:9569039

Harvey, P.; Warn, A.; Dobbin, S.; Arakaki, N.; Daikuhara, Y.; Jaurand, M. C.; Warn, R. M.

1998-01-01

100

Changes in macrophage morphology and prolonged cell viability following exposure to polyethylene particulate in vitro.  

PubMed

The interaction of macrophages and ultra-high molecular weight polyethylene (PE) wear plays an important role in perpetuating chronic inflammation at the bone implant interface, leading to peri-implant osteolysis and mechanical failure of the implant. A model to study the interaction of human mature macrophages with orthopaedic biomaterial wear has been previously developed. With the use of the model, in this study, the mature human monocyte-derived macrophages (MDMs) were observed with light, fluorescent, and scanning electron microscopy (SEM), as well as transmission electron microscopy (TEM). The cell viability was investigated using calcein and ethidium staining. Following exposure to PE particulate, the morphology of the human MDMs was heterogeneous: rounded, flattened, and elongated. There was no morphological evidence of cytotoxicity or apoptosis. The MDM viability was not influenced by phagocytosis of PE particulate in a negative fashion. In fact, more prolonged cell viability was observed in the human MDMs exposed to PE particulate when compared to controls. PMID:12112435

Xing, Shaomo; Waddell, J E; Boynton, E L

2002-06-15

101

[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

102

Cultural, morphological, cell membrane, enzymatic, and neoplastic properties of cell lines derived from a Hodgkin's disease lymph node.  

PubMed

A neoplastic cell line (designated HuT11) has been established in continuous culture from an involved lymph node of a patient with Stage IIA Hodgkin's disease of the mixed cellularity type. The HuT11 line has been morphologically heterogeneous, consisting of mononucleate lymphoid-like cells, polygonal epithelioid cells, and mono-, bi-, and multinucleate giant cells. Four clones initiated from isolated binucleate giant cells of the HuT11 line also have been successfully established as continuous cell lines. The cloned lines have been morphologically distinct and more homogeneous, although typical giant cells have consistently appeared throughout the long-term culture of each. The HuT11 lines have grown as monolayers in McCoy's Medium 5A supplemented with 10% fetal calf serum, with generation times of 12 to 14 hr and high saturation densities. Cytogenetic studies showed that early and later passages of HuT11 cells were aneuploid, and all cell lines were successfully heterotransplanted in the hamster cheek pouch. Repeated indirect immunofluorescence examinations have shown each cell line to be negative for Epstein-Barr virus nuclear antigen. Indirect immunofluorescence tests in which monospecific immunoglobulins were used revealed positive membrane reactions for the gamma (heavy)-chain and kappa (light)-chain of human immunoglobulin G in approximately 20% of viable cells in each line; however, direct immunofluorescence with anti-human immunoglobulin G F(ab')2 reagent failed to confirm these reactions. Rosette tests for B- and T-lymphocyte and macrophage membrane receptors yielded negative results. All cell lines were strongly phagocytic for latex particles and neutral red dye. Cytochemical stains of the monolayers revealed abundant esterase, fluoride-resistant nonspecific esterase, acid phosphatase, and leucine aminopeptidase activities, while lysozyme assays were negative. Although some properties of the HuT11 lines have suggested a macrophage derivation, an undifferentiated lymphoid cell origin of the Hodgkin's neoplastic cell remains a possibility. PMID:209894

Roberts, A N; Smith, K L; Dowell, B L; Hubbard, A K

1978-09-01

103

Stochastic collective movement of cells and fingering morphology: no maverick cells.  

PubMed

The classical approach to model collective biological cell movement is through coupled nonlinear reaction-diffusion equations for biological cells and diffusive chemicals that interact with the biological cells. This approach takes into account the diffusion of cells, proliferation, death of cells, and chemotaxis. Whereas the classical approach has many advantages, it fails to consider many factors that affect multicell movement. In this work, a multiscale approach, the Glazier-Graner-Hogeweg model, is used. This model is implemented for biological cells coupled with the finite element method for a diffusive chemical. The Glazier-Graner-Hogeweg model takes the biological cell state as discrete and allows it to include cohesive forces between biological cells, deformation of cells, following the path of a single cell, and stochastic behavior of the cells. Where the continuity of the tissue at the epidermis is violated, biological cells regenerate skin to heal the wound. We assume that the cells secrete a diffusive chemical when they feel a wounded region and that the cells are attracted by the chemical they release (chemotaxis). Under certain parameters, the front encounters a fingering morphology, and two fronts progressing against each other are attracted and correlated. Cell flow exhibits interesting patterns, and a drift effect on the chemical may influence the cells' motion. The effects of a polarized substrate are also discussed. PMID:19804711

Ouaknin, Gaddiel Yonathan; Bar-Yoseph, Pinhas Zvi

2009-10-01

104

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

PubMed Central

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

2014-01-01

105

Regional Fibronectin and Collagen Fibril Co-Assembly Directs Cell Proliferation and Microtissue Morphology  

PubMed Central

The extracellular matrix protein, fibronectin stimulates cells to self-assemble into three-dimensional multicellular structures by a mechanism that requires the cell-dependent conversion of soluble fibronectin molecules into insoluble fibrils. Fibronectin also binds to collagen type I and mediates the co-assembly of collagen fibrils into the extracellular matrix. Here, the role of collagen-fibronectin binding in fibronectin-induced cellular self-assembly was investigated using fibronectin-null fibroblasts in an in vitro model of tissue formation. High resolution, two-photon immunofluorescence microscopy was combined with second harmonic generation imaging to examine spatial and temporal relationships among fibronectin and collagen fibrils, actin organization, cell proliferation, and microtissue morphology. Time course studies coupled with simultaneous 4-channel multiphoton imaging identified regional differences in fibronectin fibril conformation, collagen fibril remodeling, actin organization, and cell proliferation during three-dimensional cellular self-assembly. Regional differences in cell proliferation and fibronectin structure were dependent on both soluble fibronectin concentration and fibronectin-collagen interactions. Fibronectin-collagen binding was not necessary for either fibronectin matrix formation or intercellular cohesion. However, inhibiting fibronectin binding to collagen reduced collagen fibril remodeling, decreased fibronectin fibril extension, blocked fibronectin-induced cell proliferation, and altered microtissue morphology. Furthermore, continual fibronectin-collagen binding was necessary to maintain both cell proliferation and microtissue morphology. Collectively, these data suggest that the complex changes in extracellular matrix and cytoskeletal remodeling that mediate tissue assembly are driven, in part, by regional variations in cell-mediated fibronectin-collagen co-assembly. PMID:24116223

Sevilla, Carlos A.; Dalecki, Diane; Hocking, Denise C.

2013-01-01

106

The influence of retinoic acid on growth and morphology of rat exorbital lacrimal gland acinar cells in culture.  

PubMed

The lacrimal gland transports and metabolizes retinoids and may require vitamin A for normal function. To study effects of retinoic acid on morphology and growth of the lacrimal gland, rat lacrimal acinar cells were cultured in medium with serum or in serum-free medium in the presence or absence of retinoic acid. In the presence of serum, the acinar cells have a somewhat fibroblastic morphology and form confluent layers. Addition of retinoic acid to these cultures causes formation of tubule-like structures. Retinoic acid inhibits the growth of lacrimal cells in medium with serum and the cells do not reach confluence; however, the labeling of the cells with bromodeoxyuridine is not affected by retinoic acid. In serum-free medium the growth of acinar cells is reduced, but their morphology is epithelial and structures resembling secretory domes are present. Retinoic acid causes a further reduction in growth, domes are absent, and cell spreading and enlargement occurs. The effects of retinoic acid on growth and morphology of lacrimal acinar cells in culture are complex and the relevance of these observations to lacrimal function in vivo is unclear; the study demonstrates, however, that these cells are responsive to retinoic acid. PMID:7924408

Ubels, J L; Dennis, M; Lantz, W

1994-06-01

107

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. PMID:22776378

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

2012-01-01

108

Constitutively activated Rho guanosine triphosphatases regulate the growth and morphology of hairy cell leukemia cells.  

PubMed

Hairy cell leukemia (HCL) is a rare type of chronic B-cell leukemia characterized by the hairy morphology of the leukemia cells. All of 5 HCL samples and an HCL-derived cell line, BNBH-I, showed serrated edges and hairlike projections in May-Grünwald Giemsa stain and protruding actin spikes and lamellipodia in phalloidin stain. These structures were hardly detected on B-cell chronic lymphocytic leukemia (B-CLL) and precursor B-cell acute lymphocytic leukemia (B-ALL) cells. Because Rho guanosine triphosphatases (GTPases) regulate the formation of these structures, we examined the expression levels and activation states of Rho GTPases in HCL cells. RhoA, Rac1, and Cdc42 were overexpressed and constitutively activated in HCL samples and BNBH-I cells but not in B-CLL or precursor B-ALL cells. Next we overexpressed dominant-negative (DN)-RhoA, DN-Rac1, and DN-Cdc42 in BNBH-I. As a result, each DN mutant repressed the growth of BNBH-I cells by more than 50% and inhibited actin spike formation, but only DN-Racl suppressed lamellipodia formation. We also found that enforced expression of constitutively active-RhoA, Rac, or Cdc42 in the proB-cell line Ba/F3 was sufficient to induce actin spike formation, whereas none of these molecules produced lamellipodia. These results indicated that constitutively activated Rho GTPases regulate the growth and unique morphology of HCL cells. PMID:12731670

Zhang, Xian; Machii, Takashi; Matsumura, Itaru; Ezoe, Sachiko; Kawasaki, Akira; Tanaka, Hirokazu; Ueda, Shuji; Sugahara, Hiroyuki; Shibayama, Hirohiko; Mizuki, Masao; Kanakura, Yuzuru

2003-04-01

109

Morphological and structural study of seed pericarp of Opuntia ficus-indica prickly pear fruits  

Microsoft Academic Search

The morphological study of pericarp of Opuntia ficus-indica (OFI) seeds showed that the cells were mainly made up of spindle-shaped sclerenchyma fibers. The chemical composition of the pericarp revealed a significant amount of polysaccharides, with cellulose (35%) and xylan (27%). The structure of xylan and cellulose, both in isolated form and as a component of seed pericarp of OFI were

Youssef Habibi; Laurent Heux; Mostafa Mahrouz; Michel R. Vignon

2008-01-01

110

Effects of human placental serum on proliferation and morphology of human adipose tissue-derived stem cells  

Microsoft Academic Search

Media used for tissue culture may have significant effects on the growth and morphology of the adipose tissue-derived stem cells (ADSCs). As fetal bovine serum (FBS) may induce an immunological reaction and health risks, this study was designed to evaluate and compare the effects of human placental serum (HPS) on the proliferation and morphology of hADSCs. We cultured hADSCs for

H Shafaei; A Esmaeili; M Mardani; S Razavi; B Hashemibeni; M H Nasr-Esfahani; M B Shiran; E Esfandiari

2011-01-01

111

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

112

The morphological classification of red cells using an image analysing computer.  

PubMed

Image analysis provides a potential method for automation in the examination of blood films. In order to assess the applicability of this technique to red cell morphology, a scheme has been defined for the classification of red cells into six categories, namely, round cells, elongated cells, tear drop poikilocytes, helmet cells, irregular cells and spherocytes. A study was carried out to determine the consistency which observers classified red cells according to this scheme. Measurements of area, perimeter, maximum diameter and integrated optical denisty of fixed, Romanowsky-stained red cells were made using an image analysing computer. A multivariate classifier based on parameters derived from these measurements, namely cell area and the quotients of integrated density over area, area over the square of perimeter and perimeter over maximum diameter was also used to classify red cells into the above categories. It was found that the inherent error of the machine-based classifier was of the same order as the degree of inconsistency encoutered between trained observers. The significance of these findings is discussed. PMID:1247494

Bentley, S A; Lewis, S M

1976-02-01

113

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

114

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. PMID:9284136

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

1997-01-01

115

A Chandra Study of Nearby Hybrid Morphology Radio Source  

NASA Astrophysics Data System (ADS)

It has been suggested that the unusual morphology of `hybrid morphology radio sources', or HyMors, strongly constrains the theoretical mechanisms proposed for the Fanaroff-Riley (FR) morphological dichotomy. Here, we propose a Chandra study of a nearby HyMors, MRC0131-367, and request 36 ks Chandra time to test the hypothesis that external environmental factors influence the jet structure by carrying out a systematic investigation of its hot-gas environment. Our observations will help to answer the questions (i) `what causes the differences between FR-I and FR-II radio structures?', and (ii) `what role does the environment play in the relationship between these two?'

Lal, Dharam

2013-09-01

116

[Surface charge of mouse neuroblastoma cells and changes during growth and morphologic differentiation of the cell population].  

PubMed

Microelectrophoresis method was used to study the surface charge of murine neuroblastoma cells (clone C1300-N18TG2). It was shown that the surface charge of these cells was determined mainly by anionic groups of the membrane which were distributed with density 0.2 e/nm3 in the layer covering its outer surface. The thickness of this layer was about 10 nm. These groups interacted with Ca ions (binding constant Kca-10-50 l/mol) and were titrated according to pK-3.8. Trypsin, neuraminidase and N-bromosuccinimide (which irreversibly neutralize the carboxylic groups of proteins) decreased the electrophoretic mobility of neuroblastoma cells while tosylchloride (a specific reagent for aminogroups) slightly increased it. The surface charge depended also on the conditions of cultivation of cell population. Morphological cell differentiation induced by removing the serum from the culture medium increased their mobility by about 30%. During the cultivation of cells in a medium with 10 or 50% of serum variations of the their mean electrophoretic mobility value were observed which were opposite-phase to the value of the daily increment of the number of cells. It was assumed that these effects were connected with partial self-synchronization of cell population. It is concluded that the surface charge of the neuroblastoma cells determined by microelectrophoresis method is mainly determined by the carboxylic groups of membrane periphery proteins and gangliosides and the content of these membrane components depends on the stage of cell development. PMID:4000300

Dolgaia, E V; Mironov, S L; Pogorelaia, N Kh

1985-01-01

117

Isolation and morphological studies of a variant of Ceratodon purpureus  

Microsoft Academic Search

Summary Morphological variants from protonema ofCeratodon purpureus (Hedw.) were obtained using nitrosoguanidine (NTG). In one of the variants, reduced growth was accompagnied by hyperbranching and inhibition of caulogenesis. The deposition of branches in this strain can be studied by enzymatic analysis.

M. Larpent-Gourgaud; M. P. Aumaitre

1982-01-01

118

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

119

[Morphological changes of THP-1 tumor cells exposed to dopamine in vitro].  

PubMed

The effect of dopamine (DA) on the viability and morphology of cultured tumor THP-1 cells (human acute monocytic leukemia) was studied. DA in concentration of 10(-5) M had virtually no effect on the culture, while in concentration of 10(-4) M to 10(-3) M it stopped the growth and caused a sharp increase in cell death after 24 and 48 hours. Incubation with DA reduced the cell diameter, progressively increased their vacuolization and intensity of fluorescence after treatment by Falck method. Electron microscopical study has shown that cells exposed for 1 day to DA in the concentrations starting with 10(-4) M, demonstrated smoothing of their surface with the disappearance of microvilli and clasmatosis vesicles, actin filaments perforating the plasma membrane, the emergence of an increasingly dense network of filaments in the cytosole and karyoplasm and, finally, apoptotic cell death. It is suggested that the oncotherapeutic cellular target for DA is a cytosolic G-actin, which at a certain DA concentration, turns into filaments that damage the cells, break the cell cycle and cause cell death. PMID:23659038

Parnyshkova, Ye Yu; Bezgina, Ye N; Lavrovskaya, V P; Pavlik, L L; Lezhnev, E I; Moshkov, D A

2012-01-01

120

On the synchrony of morphological and molecular signaling events in cell migration  

E-print Network

On the synchrony of morphological and molecular signaling events in cell migration Justin Dauwels,cia}@brain.riken.jp Abstract. This paper investigates the dynamics of cell migration, which is the movement of a cell towards known to induce filamentous structures that enable cells to migrate. Results show a significant delay

Cichocki, Andrzej

121

Morphological observation on cell death and phagocytosis induced by ultraviolet irradiation in a cultured human lens epithelial cell line.  

PubMed

The purpose of this study is to observe dynamic morphological changes induced by ultraviolet (UV) irradiation in a cultured human lens epithelial cell line using electron microscopy, cell viability staining, time-lapsed videography and immunohistochemistry. Human lens epithelial cell line SRA 01-04 was cultured in Dulbecco's Modified Eagle Medium (DMEM) containing 20% fetal bovine serum. Subconfluent cells were irradiated under a bank of UV lamps, which emitted 275-400 nm radiation with a maximum at 310 nm. The UV intensity was 20 microW cm(-2)at dosages from 0 to 10 mJ cm(-2). Alterations in the morphology of the living cells were monitored and recorded with phase-contrast microscopy and time-lapsed videography. At different times, the cells were fixed and examined by transmission electron microscopy (TEM), diamidinophenolindole (DAPI) staining, and in situ immunohistochemistry using TdT-mediated dUTP-biotin nick end labeling (TUNEL). Cell viability was also assessed with crystal violet staining. At low doses of UV exposure (2-5 mJ cm(-2)), time-lapsed videography revealed definitive cell death that appeared to be primarily apoptotic. The dead cell debris was engulfed and phagocytosed by neighboring living cells. Phase-contrast microscopy and TEM demonstrated that, at UV 10 mJ cm(-2), the cells not only showed typical apoptosis such as nuclear membrane shrinkage, chromatin condensation, and fragmentation into apoptotic bodies, but also necrosis such as swelling of the nucleus and cell body, and disruption of the plasma membrane. In support, DNA staining and in situ immunohistochemical reactions in the UV irradiated cells were both positive. The phagocytotic process was also seen with TEM. UV irradiation thus appears to cause both apoptosis and necrosis in the cultured human lens epithelial cell line. Active migration and phagocytosis of the cells appear to be stimulated by UV-induced damage. These findings may also aid in the understanding of UV injury and repair mechanisms of lens epithelial cells in vivo. PMID:11095913

Shui, Y B; Sasaki, H; Pan, J H; Hata, I; Kojima, M; Yamada, Y; Hirai, K I; Takahashia, N; Sasaki, K

2000-12-01

122

Toward bulk heterojunction polymer solar cells with thermally stable active layer morphology  

NASA Astrophysics Data System (ADS)

When state-of-the-art bulk heterojunction organic solar cells with ideal morphology are exposed to prolonged storage or operation at elevated temperatures, a thermally induced disruption of the active layer blend can occur, in the form of a separation of donor and acceptor domains, leading to diminished photovoltaic performance. Toward the long-term use of organic solar cells in real-life conditions, an important challenge is, therefore, the development of devices with a thermally stable active layer morphology. Several routes are being explored, ranging from the use of high glass transition temperature, cross-linkable and/or side-chain functionalized donor and acceptor materials, to light-induced dimerization of the fullerene acceptor. A better fundamental understanding of the nature and underlying mechanisms of the phase separation and stabilization effects has been obtained through a variety of analytical, thermal analysis, and electro-optical techniques. Accelerated aging systems have been used to study the degradation kinetics of bulk heterojunction solar cells in situ at various temperatures to obtain aging models predicting solar cell lifetime. The following contribution gives an overview of the current insights regarding the intrinsic thermally induced aging effects and the proposed solutions, illustrated by examples of our own research groups.

Cardinaletti, Ilaria; Kesters, Jurgen; Bertho, Sabine; Conings, Bert; Piersimoni, Fortunato; D'Haen, Jan; Lutsen, Laurence; Nesladek, Milos; Van Mele, Bruno; Van Assche, Guy; Vandewal, Koen; Salleo, Alberto; Vanderzande, Dirk; Maes, Wouter; Manca, Jean V.

2014-01-01

123

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

2014-07-21

124

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

PubMed Central

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

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

2013-01-01

125

Mapping the complex morphology of cell interactions with nanowire substrates using FIB-SEM.  

PubMed

Using high resolution focused ion beam scanning electron microscopy (FIB-SEM) we study the details of cell-nanostructure interactions using serial block face imaging. 3T3 Fibroblast cellular monolayers are cultured on flat glass as a control surface and on two types of nanostructured scaffold substrates made from silicon black (Nanograss) with low- and high nanowire density. After culturing for 72 hours the cells were fixed, heavy metal stained, embedded in resin, and processed with FIB-SEM block face imaging without removing the substrate. The sample preparation procedure, image acquisition and image post-processing were specifically optimised for cellular monolayers cultured on nanostructured substrates. Cells display a wide range of interactions with the nanostructures depending on the surface morphology, but also greatly varying from one cell to another on the same substrate, illustrating a wide phenotypic variability. Depending on the substrate and cell, we observe that cells could for instance: break the nanowires and engulf them, flatten the nanowires or simply reside on top of them. Given the complexity of interactions, we have categorised our observations and created an overview map. The results demonstrate that detailed nanoscale resolution images are required to begin understanding the wide variety of individual cells' interactions with a structured substrate. The map will provide a framework for light microscopy studies of such interactions indicating what modes of interactions must be considered. PMID:23326412

Wierzbicki, Rafa?; Købler, Carsten; Jensen, Mikkel R B; Lopaci?ska, Joanna; Schmidt, Michael S; Skolimowski, Maciej; Abeille, Fabien; Qvortrup, Klaus; Mølhave, Kristian

2013-01-01

126

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

127

A Rapid Method Combining Golgi and Nissl Staining to Study Neuronal Morphology and Cytoarchitecture  

PubMed Central

The Golgi silver impregnation technique gives detailed information on neuronal morphology of the few neurons it labels, whereas the majority remain unstained. In contrast, the Nissl staining technique allows for consistent labeling of the whole neuronal population but gives very limited information on neuronal morphology. Most studies characterizing neuronal cell types in the context of their distribution within the tissue slice tend to use the Golgi silver impregnation technique for neuronal morphology followed by deimpregnation as a prerequisite for showing that neuron's histological location by subsequent Nissl staining. Here, we describe a rapid method combining Golgi silver impregnation with cresyl violet staining that provides a useful and simple approach to combining cellular morphology with cytoarchitecture without the need for deimpregnating the tissue. Our method allowed us to identify neurons of the facial nucleus and the supratrigeminal nucleus, as well as assessing cellular distribution within layers of the dorsal cochlear nucleus. With this method, we also have been able to directly compare morphological characteristics of neuronal somata at the dorsal cochlear nucleus when labeled with cresyl violet with those obtained with the Golgi method, and we found that cresyl violet–labeled cell bodies appear smaller at high cellular densities. Our observation suggests that cresyl violet staining is inadequate to quantify differences in soma sizes. (J Histochem Cytochem 56:539–550, 2008) PMID:18285350

Pilati, Nadia; Barker, Matthew; Panteleimonitis, Sofoklis; Donga, Revers; Hamann, Martine

2008-01-01

128

Functional morphology of the neuropeptidergic light-yellow-cell system in pulmonate snails.  

PubMed

The light yellow neuropeptidergic cell system of the basommatophoran snail Lymnaea stagnalis is homologous to the R3-R14 system of the opisthobranch Aplysia californica, and produces three different neuropeptides. Systems homologous to the light yellow cells of Lymnaea stagnalis have been investigated morphologically in two Basommatophora (Lymnaea ovata, Bulinus truncatus) and three Stylommatophora (Helix aspersa, Cepaea nemoralis, Deroceras reticulatum). To this end, an antibody to synthetic light-yellow-cell peptide-II and oligonucleotides to mRNAs encoding parts of peptide-I and peptide-III, were used. The in situ hybridization probes gave negative results. On the other hand, neuronal cell clusters were observed in the central nervous system of all species studied by immunocytochemistry. These clusters were located in the ganglia of the visceral complex. The neurons project axons into all nerves of these ganglia, especially into the pallial nerves, into the connective tissue of the central nervous system, and into the neuropile of various ganglia. The morphology of the systems is similar to that of the light-yellow-cell system of Lymnaea stagnalis. In all species, the wall of the aorta was innervated by immunoreactive axons. Peripheral innervation by the light-yellow-cell system was investigated in Helix aspersa and Deroceras reticulatum. Serial and alternate sections of whole snails were studied. Reconstructions were made of the heart-kidney-lung complex of these animals. In both species, the muscular vessels of the pulmonary system at the right side of the body were strongly innervated by immunoreactive axons.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7954689

Boer, H H; Montagne-Wajer, C

1994-09-01

129

A mathematical morphology approach to cell shape analysis  

E-print Network

.) is fundamental in quantitative cytology. Anomalies and variations from the typical cell are as- sociated of examples from haematological cytology [ANG06] (to classify red blood cells) and from cell-based high

Angulo,Jesús

130

Morphological analysis of cell growth mutants in Physcomitrella.  

PubMed

This protocol describes a quantitative analysis of the morphology of small plants from the moss Physcomitrella patens. The protocol can be used for the analysis of growth phenotypes produced by transient RNA interference or for the analysis of stable mutant plants. Information is presented to guide the investigator in the choice of vectors and basic conditions to perform transient RNA interference in moss. Detailed directions and examples for fluorescence image acquisition of small regenerating moss plants are provided. Instructions for the use of an ImageJ-based macro for quantitative morphological analysis of these plants are also provided. PMID:24132431

Bibeau, Jeffrey P; Vidali, Luis

2014-01-01

131

AMPK Knockdown in Placental Trophoblast Cells Results in Altered Morphology and Function.  

PubMed

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

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

2014-12-01

132

Equine pituitary adenoma: a functional and morphological study.  

PubMed

Clinico-pathological correlations in horses with pituitary adenomas are poorly understood. This paper describes the functional and morphological features of five cases of equine pituitary adenoma and of a case of multinodular pituitary hyperplasia. New findings reported include immunoreactivity for beta-lipotropin (beta-LPH), beta-melanocyte-stimulating hormone (beta-MSH), gamma 3-MSH, prolactin (PRL), and follicle-stimulating hormone (FSH) in neoplastic cells of the pituitary adenoma; and, in the multinodular hyperplasia, beta-LPH, beta-endorphin (beta-END), alpha-MSH, beta-MSH, gamma 3-MSH and FSH immunoreactivity. It is suggested that the equine pituitary syndrome does not correspond to human Cushing's disease, as generally accepted, but is related to the overproduction of several pro-opiomelanocortin (POMC)-derived peptides by the cells of the tumour or hyperplastic nodules. PMID:8245232

Boujon, C E; Bestetti, G E; Meier, H P; Straub, R; Junker, U; Rossi, G L

1993-08-01

133

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

PubMed Central

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

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

2014-01-01

134

Effects of early environment on granule cell morphology in the dentate gyrus of the guinea-pig  

Microsoft Academic Search

The aim of the present study was to determine whether early environment affects the morphology of the dentate gyrus granule cells in the guinea-pig, a rodent whose brain is at an advanced stage of maturation at birth. Male and female guinea-pigs were assigned at six to seven days of age to either a control (social) or an isolated environment where

R Bartesaghi; A Serrai

2001-01-01

135

Cytostasis and morphological changes induced by mifepristone in human metastatic cancer cells involve cytoskeletal filamentous actin reorganization and impairment of cell adhesion dynamics  

PubMed Central

Background Changes in cell shape and plasticity in cytoskeletal dynamics are critically involved in cell adhesion, migration, invasion and the overall process of metastasis. Previous work in our laboratory demonstrated that the synthetic steroid mifepristone inhibited the growth of highly metastatic cancer cells, while simultaneously causing striking changes in cellular morphology. Here we assessed whether such morphological alterations developed in response to cytostatic concentrations of mifepristone are reversible or permanent, involve rearrangement of cytoskeletal proteins, and/or affect the adhesive capacity of the cells. Methods Cancer cell lines of the ovary (SKOV-3), breast (MDA-MB-231), prostate (LNCaP), and nervous system (U87MG) were exposed to cytostatic concentrations of mifepristone and studied by phase-contrast microscopy. The transient or permanent nature of the cytostasis and morphological changes caused by mifepristone was assessed, as well as the rearrangement of cytoskeletal proteins. De-adhesion and adhesion assays were utilized to determine if mifepristone-arrested and morphologically dysregulated cells had abnormal de-adhesion/adhesion dynamics when compared to vehicle-treated controls. Results Mifepristone-treated cells displayed a long, thin, spindle-like shape with boundaries resembling those of loosely adhered cells. Growth arrest and morphology changes caused by mifepristone were reversible in SKOV-3, MDA-MB-231 and U87MG, but not in LNCaP cells that instead became senescent. All cancer cell types exposed to mifepristone displayed greatly increased actin ruffling in association with accelerated de-adhesion from the culture plate, and delayed adhesion capacity to various extracellular matrix components. Conclusions Cytostatic concentrations of mifepristone induced alterations in the cellular structure of a panel of aggressive, highly metastatic cancer cells of different tissues of origin. Such changes were associated with re-distribution of actin fibers that mainly form non-adhesive membrane ruffles, leading to dysregulated cellular adhesion capacity. PMID:23351358

2013-01-01

136

Sedimentation and River Morphology Studies in the Bureau of Reclamation  

Microsoft Academic Search

This paper provides a brief introduction to some of the recent sedimentation and river morphology studies conducted by the Sedimentation and River Hydraulics Group of the U.S. Bureau of Reclamation. They are: • Generalized Stream Tube model for Alluvial River Simulation (GSTARS) versions 2.0, 2.1, and 3.0 • Unsteady flow and sediment transport simulation model for dam break analysis •

Chih Ted Yang

137

Morphological and functional differentiation in BE(2)-M17 human neuroblastoma cells by treatment with Trans-retinoic acid  

PubMed Central

Background Immortalized neuronal cell lines can be induced to differentiate into more mature neurons by adding specific compounds or growth factors to the culture medium. This property makes neuronal cell lines attractive as in vitro cell models to study neuronal functions and neurotoxicity. The clonal human neuroblastoma BE(2)-M17 cell line is known to differentiate into a more prominent neuronal cell type by treatment with trans-retinoic acid. However, there is a lack of information on the morphological and functional aspects of these differentiated cells. Results We studied the effects of trans-retinoic acid treatment on (a) some differentiation marker proteins, (b) types of voltage-gated calcium (Ca2+) channels and (c) Ca2+-dependent neurotransmitter ([3H] glycine) release in cultured BE(2)-M17 cells. Cells treated with 10 ?M trans-retinoic acid (RA) for 72 hrs exhibited marked changes in morphology to include neurite extensions; presence of P/Q, N and T-type voltage-gated Ca2+ channels; and expression of neuron specific enolase (NSE), synaptosomal-associated protein 25 (SNAP-25), nicotinic acetylcholine receptor ?7 (nAChR-?7) and other neuronal markers. Moreover, retinoic acid treated cells had a significant increase in evoked Ca2+-dependent neurotransmitter release capacity. In toxicity studies of the toxic gas, phosgene (CG), that differentiation of M17 cells with RA was required to see the changes in intracellular free Ca2+ concentrations following exposure to CG. Conclusion Taken together, retinoic acid treated cells had improved morphological features as well as neuronal characteristics and functions; thus, these retinoic acid differentiated BE(2)-M17 cells may serve as a better neuronal model to study neurobiology and/or neurotoxicity. PMID:23597229

2013-01-01

138

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

139

Characterization of morphological response of red cells in a sucrose solution.  

PubMed

The dynamics of red cell shape changes following transfer into sucrose media having a low chloride content was studied. Based on a large number of measurements, six types of morphological response (MR), differing both in the degree of shape changes and the time course of the process, were identified. The most prominent type of response is a triphasic sequence of shape changes consisting of a fast transformation into a sphere (phase 1), followed by restoration of the discoid shape (phase 2) and final transformation into spherostomatocytes (phase 3), with individual parameters which could vary significantly. It was found that individual morphological response exhibited day to day variations, depending on the initial state of the red blood cells and the donor, but to a larger extent depended on the composition of the sucrose solution, such as concentration and type of buffers, the presence of EDTA, calcium, as well as very small amounts of extracellular hemoglobin. MR shows strong pH and ionic strength dependence. Low pH inhibited phase 1 and high pH changed dramatically the time course of the response. Increasing ionic strength inhibited all phases of MR, and at concentrations above 10-20 mM NaCl it was fully suppressed. Tris and phosphate were also inhibitory whereas HEPES, MOPS and Tricine were less effective. MR occurred also in hypertonic or hypotonic sucrose solutions, with exception of extreme hypotonicity due to volume restrictions. It is concluded that strong membrane depolarization per se is not a causal factor leading to MR, and its different phases could be regulated independently. For some types of morphological response the fast shape transformation from sphere to disc and back to sphere occurs within a 10 s time interval and could be accelerated several fold in the presence of a small amount of hemoglobin. It is suggested that MR represents a type of general cell reaction that occurs upon exposure to low ionic strength. PMID:19249232

Rudenko, Sergey V

2009-01-01

140

Statistical Dynamics of Flowing Red Blood Cells by Morphological Image Processing  

PubMed Central

Blood is a dense suspension of soft non-Brownian cells of unique importance. Physiological blood flow involves complex interactions of blood cells with each other and with the environment due to the combined effects of varying cell concentration, cell morphology, cell rheology, and confinement. We analyze these interactions using computational morphological image analysis and machine learning algorithms to quantify the non-equilibrium fluctuations of cellular velocities in a minimal, quasi-two-dimensional microfluidic setting that enables high-resolution spatio-temporal measurements of blood cell flow. In particular, we measure the effective hydrodynamic diffusivity of blood cells and analyze its relationship to macroscopic properties such as bulk flow velocity and density. We also use the effective suspension temperature to distinguish the flow of normal red blood cells and pathological sickled red blood cells and suggest that this temperature may help to characterize the propensity for stasis in Virchow's Triad of blood clotting and thrombosis. PMID:19214200

Higgins, John M.; Eddington, David T.; Bhatia, Sangeeta N.; Mahadevan, L.

2009-01-01

141

Effects of Environmental Cl Levels on Cl Uptake and Mitochondria-rich Cell Morphology in Gills of the Stenohaline Goldfish, Carassius auratus  

Microsoft Academic Search

Il-Chi Chang, Tsung-Han Lee, Hong-Chih Wu and Pung-Pung Hwang (2002) Effects of environmental Cl- levels on Cl- uptake and mitochondria-rich cell morphology in gills of the stenohaline goldfish, Carassius aura- tus. Zoological Studies 41(3): 236-243. The objective of the present study was to examine the correlation between morphological changes in gill MR cells and modulations in Cl- uptake in a

Il-Chi Chang; Tsung-Han Lee; Hong-Chih Wu; Pung-Pung Hwang

2002-01-01

142

Cell-adhesion and morphological changes are not sufficient to support anchorage-dependent cell growth via non-integrin-mediated attachment.  

PubMed

Cell-adhesion and spread are important for cell survival. Although extensive studies have suggested several potential mechanisms of action, it is not yet clear how important cell-morphological change per se contributes to the cell-surviving signal. We employed a non-integrin-mediated cell-adhesion system to explore this question. BHK-Japanese encephalitis virus (JEV) cells (BHK21 cells that are persistently infected with JEV) express a large amount of JEV-envelope protein (JEV E) on their surfaces, and can attach and form pseudopodia on the anti-JEV E antibody-coated substrates. However, cells that adhered on the antibody substrate underwent a caspase-3-mediated apoptosis together with a down-regulation of mitogen-activated protein kinase activity within 20 h after adhesion, which indicates that viral-protein-mediated cell-adhesion and cell-spread are not sufficient for supporting cell survival. This provides a different perspective for the study of the relationships between the cell-morphological change and the cell-survival signal. PMID:12662969

Chang, Hsin-Hou; Kau, Jyh-Hwa; Lo, Szecheng J; Sun, Der-Shan

2003-01-01

143

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

144

Single-cell morphological data reveals signaling network architecture  

E-print Network

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

Nir, Oaz

2010-01-01

145

Morphology, Growth, and Size Limit of Bacterial Cells  

PubMed Central

Bacterial cells utilize a living peptidoglycan network (PG) to separate the cell interior from the surroundings. The shape of the cell is controlled by PG synthesis and cytoskeletal proteins that form bundles and filaments underneath the cell wall. The PG layer also resists turgor pressure and protects the cell from osmotic shock. We argue that mechanical influences alter the chemical equilibrium of the reversible PG assembly and determine the cell shape and cell size. Using a mechanochemical approach, we show that the cell shape can be regarded as a steady state of a growing network under the influence of turgor pressure and mechanical stress. Using simple elastic models, we predict the size of common spherical and rodlike bacteria. The influence of cytoskeletal bundles such as crescentin and MreB are discussed within the context of our model. PMID:20867742

Jiang, Hongyuan; Sun, Sean X.

2010-01-01

146

ORIGINAL ARTICLE ATP-induced morphological changes in supporting cells  

E-print Network

The developing cochlea of mammals contains a large group of columnar-shaped cells, which together form cochlea contains a mass of columnar- shaped cells that lie immediately medial to inner hair cells­3]. This pseudo-stratified epithelium forms shortly after the out- growth of the cochlear duct from the otocyst

Bergles, Dwight

147

Hybrid Solar Cells with Prescribed Nanoscale Morphologies Based onHyperbranched Semiconductor Nanocrystals  

SciTech Connect

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

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

2006-09-09

148

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

NASA Technical Reports Server (NTRS)

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

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

1997-01-01

149

Novel morphological features in the death of MCF-7 human breast cancer cells after exposure to anticancer drugs.  

PubMed

Cell death of human breast cancer cell line MCF-7/pDsRed2-Mito, caused by independent- or multi-administration of three anticancer drugs, cyclophosphamide [CPA], doxorubicin [DXR], and 5-fluorouracil [5-FU], was studied using fluorescence and electron microscopy. In our previous study using cell viability assays, microscopic inspection of heterochromatin condensation, a DNA fragmentation assay, and flow cytometric analyses, the death of MCF-7 cells was classified into two groups. The cell death induced by CPA or 5-FU was classified as apoptotic, while the cell death induced by DXR treatment or a mixture of all three anticancer drugs was classified as non-apoptotic. Here, we examined the morphology of the whole cell and its organelles, including the mitochondria, using electron microscopy. Mitochondria are of particular interest because they are the key organelle for the molecular apoptotic-death cascade. To monitor mitochondrial morphology, we used our previously constructed MCF-7/pDsRed2-Mito line, generated by introducing the pDsRed2-Mito vector into MCF-7 cells. The mitochondria in these cells emit red fluorescence. We found that the administration of DXR alone or of all three anticancer drugs together resulted in the clumping of the red-fluorescent materials on both sides of the round dying cells, interrupted by the nucleus. Detailed electron microscopic observation revealed that the novel morphology of the dying MCF-7 cells might be owing, not to destruction of the mitochondrial membrane, but to the tight structure of the nuclear membrane. Other anticancer drugs showed different, characteristic features in electron microscopic images, which suggested that death induced by anti-cancer drugs in the human breast cancer cell line, MCF-7, may result from any of a number of diverse processes. PMID:23136722

Kugawa, F; Dalkhuren, S-O; Ueno, A; Yamashita, K

2012-10-01

150

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

PubMed Central

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

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

2010-01-01

151

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

PubMed Central

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

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

2014-01-01

152

The effect of oxygen on the growth and cell morphology of Helicobacter pylori.  

PubMed

The in vitro effect of progressive oxygen decrease on the growth and morphology of Helicobacter pylori was studied. H. pylori ATCC 43,504 was used for the experiments. The strain inoculated in Brucella broth plus fetal calf serum was incubated under a controlled atmosphere with oxygen concentration from 5 to 0%. CFU ml-1 and bacterial morphology were detected at the time of spreading and at 24 h, 72 h, 7 days and 14 days. A detailed ultrastructural investigation of the bacterial cells, grown in different experimental conditions, was performed by scanning electron microscopy. Oxygen deprivation produced a rapid reduction of CFU ml-1. In particular, a significant reduction of viable bacteria was recorded at 72 h of incubation in the presence of 1% oxygen and anaerobiosis, and 0 CFU ml-1 was found after 7 days of incubation at the above mentioned oxygen concentrations. The coccoid phenotype was already prevalent after 24 h of incubation with a progressive tendency to aggregate in clusters. These clusters were progressively larger, depending on the reduction of oxygen concentration, since the aggregation phenomenon can be the expression of a hypothesized mechanism of protection among bacterial cells. PMID:9812358

Donelli, G; Matarrese, P; Fiorentini, C; Dainelli, B; Taraborelli, T; Di Campli, E; Di Bartolomeo, S; Cellini, L

1998-11-01

153

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

154

Induction of Morphological Changes in Human Embryo Liver Cells by the Pyrrolizidine Alkaloid Lasiocarpine  

PubMed Central

The pyrrolizidine alkaloids have been implicated in the aetiology of liver disease in man and in animals. Studies of the effects of lasiocarpine indicate that they have several and perhaps independent effects on human liver cells in culture. These may be summarized as follows: 1. Nuclear and nucleolar changes which are probably related to the alkylation of DNA and ensuing inhibition of nucleic acid and protein synthesis. 2. The induction of possible chromosomal damage and mutation. 3. A generalized reduction of the metabolic activities of the cells due to membrane and mitochondrial damage, and to alkylation and inactivation of cell enzymes and proteins. 4. A long-term inhibition of mitosis leading to the formation of giant cells (“megalocytes”). The morphological effects induced by a number of the pyrrolizidine alkaloids were very similar but the pattern of metabolic changes varied somewhat. It is believed that the hepatotoxic effects are not due to the pyrrolizidine alkaloids themselves but to metabolic derivatives formed by the cell. ImagesFigs. 3-5Figs. 1-2 PMID:5032090

Armstrong, Sylvia J.; Zuckerman, A. J.; Bird, R. G.

1972-01-01

155

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

PubMed Central

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

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

2013-01-01

156

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

PubMed Central

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

Irani, Niloufer G; Grotewold, Erich

2005-01-01

157

Emergence of Large-Scale Cell Morphology and Movement from Local Actin Filament  

E-print Network

Emergence of Large-Scale Cell Morphology and Movement from Local Actin Filament Growth Dynamics-scale cytoskeletal molecular activities. Because the properties of the actin cytoskeleton can be modulated by actin of cells within a population. Thus, local changes in actin filament dynamics due to Ena/VASP activity

Mogilner, Alex

158

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

E-print Network

, designated mitochondrial protein X (MIX), is an oligomeric protein probably located in the inner membrane#12;A mitochondrial protein affects cell morphology, mitochondrial segregation and virulence with the nucleus and plays a crucial role in cell division. However, despite its importance and potential as a drug

McFadden, Geoff

159

Nak1, an Essential Germinal Center (GC) Kinase Regulates Cell Morphology and Growth in Schizosaccharomyces pombe*  

E-print Network

in loss of cell polarity remain unclear. The p21-activated kinases (PAKs)1 have been implicatedNak1, an Essential Germinal Center (GC) Kinase Regulates Cell Morphology and Growth kinase belonging to the group II germinal center kinase (GCK) family, in Schizosac- charomyces pombe. We

Young, Dallan

160

Massive granular cell ameloblastoma with dural extension and atypical morphology.  

PubMed

Ameloblastomas are rare histologically benign, locally aggressive tumors arising from the oral ectoderm that occasionally reach a gigantic size. Giant ameloblastomas are a rarity these days with the advent of panoramic radiography in routine dental practice. Furthermore, the granular cell variant is an uncommon histological subtype of ameloblastoma where the central stellate reticulum like cells in tumor follicles is replaced by granular cells. Although granular cell ameloblastoma (GCA) is considered to be a destructive tumor with a high recurrence rate, the significance of granular cells in predicting its biologic behavior is debatable. However, we present a rare case of giant GCA of remarkable histomorphology showing extensive craniofacial involvement and dural extension that rendered a good prognosis following treatment. PMID:25395775

Raghunath, Vandana; Rath, Rachna; Kamal, Firoz; Misra, Satya Ranjan

2014-10-01

161

Massive granular cell ameloblastoma with dural extension and atypical morphology  

PubMed Central

Ameloblastomas are rare histologically benign, locally aggressive tumors arising from the oral ectoderm that occasionally reach a gigantic size. Giant ameloblastomas are a rarity these days with the advent of panoramic radiography in routine dental practice. Furthermore, the granular cell variant is an uncommon histological subtype of ameloblastoma where the central stellate reticulum like cells in tumor follicles is replaced by granular cells. Although granular cell ameloblastoma (GCA) is considered to be a destructive tumor with a high recurrence rate, the significance of granular cells in predicting its biologic behavior is debatable. However, we present a rare case of giant GCA of remarkable histomorphology showing extensive craniofacial involvement and dural extension that rendered a good prognosis following treatment.

Raghunath, Vandana; Rath, Rachna; Kamal, Firoz; Misra, Satya Ranjan

2014-01-01

162

Cell motility, morphology, viability and proliferation in response to nanotopography on silicon black  

NASA Astrophysics Data System (ADS)

Knowledge of cells' interactions with nanostructured materials is fundamental for bio-nanotechnology. We present results for how individual mouse fibroblasts from cell line NIH3T3 respond to highly spiked surfaces of silicon black that were fabricated by maskless reactive ion etching (RIE). We did standard measurements of cell viability, proliferation, and morphology on various surfaces. We also analyzed the motility of cells on the same surfaces, as recorded in time lapse movies of sparsely populated cell cultures. We find that motility and morphology vary strongly with nano-patterns, while viability and proliferation show little dependence on substrate type. We conclude that motility analysis can show a wide range of cell responses e.g. over a factor of two in cell speed to different nano-topographies, where standard assays, such as viability or proliferation, in the tested cases show much less variation of the order 10-20%.Knowledge of cells' interactions with nanostructured materials is fundamental for bio-nanotechnology. We present results for how individual mouse fibroblasts from cell line NIH3T3 respond to highly spiked surfaces of silicon black that were fabricated by maskless reactive ion etching (RIE). We did standard measurements of cell viability, proliferation, and morphology on various surfaces. We also analyzed the motility of cells on the same surfaces, as recorded in time lapse movies of sparsely populated cell cultures. We find that motility and morphology vary strongly with nano-patterns, while viability and proliferation show little dependence on substrate type. We conclude that motility analysis can show a wide range of cell responses e.g. over a factor of two in cell speed to different nano-topographies, where standard assays, such as viability or proliferation, in the tested cases show much less variation of the order 10-20%. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr11455k

?opaci?ska, Joanna M.; Gr?dinaru, Cristian; Wierzbicki, Rafal; Købler, Carsten; Schmidt, Michael S.; Madsen, Martin T.; Skolimowski, Maciej; Dufva, Martin; Flyvbjerg, Henrik; Mølhave, Kristian

2012-05-01

163

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

PubMed Central

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

2009-01-01

164

Hypergravity affects morphology and function in microvascular endothelial cells  

Microsoft Academic Search

Cardiovascular diseases are major health problems in astronauts and pilots. The basic problem in cardiovascular diseases is\\u000a the loss of function by vascular endothelium. It has been demonstrated that changes in inertial conditions (i.e. hypo- and\\u000a hypergravity) can affect both phenotypic and genotypic expression in endothelial cells. This report describes the effects\\u000a observed in endothelial cells from coronary post-capillary venules

Monica Monici; Nicola Marziliano; Venere Basile; Giovanni Romano; Antonio Conti; Silvia Pezzatini; Lucia Morbidelli

2006-01-01

165

Measurement of DNA content in single cells morphologically identified on smears.  

PubMed

A method was developed for measuring the nuclear DNA content in single cells previously identified on a bone marrow smear stained by the Wright-Giemsa method. The smear was first photographed and the location of individual cells, identified by morphology, was recorded on a cell map. The smear was then bleached with 50% acid ethanol and absolute methanol, and re-stained by the Feulgen method in 0.05% pararosaniline Schiff's reagent (pH 2.3) at 7 degrees C for 10 min. Nuclear red fluorescence was observed and the intensity of this fluorescence was proportional to the amount of DNA after prior irradiation of smears with green light for 9 hr. The method is useful for measuring cell DNA content in heterogeneous cell populations when morphological cell identification is required. PMID:3745905

Maruo, N; Nakabo, T; Kondo, M

1986-10-01

166

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

167

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

PubMed Central

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

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

2014-01-01

168

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

169

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

170

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

171

Microinjection of recombinant p21rho induces rapid changes in cell morphology  

Microsoft Academic Search

The rho proteins, p21 ~, are ubiquitously expressed guanine nucleotide binding proteins with ,'o30% amino acid homology to p21'% but their bio- chemical function is unknown. We show here that mi- croinjection of constitutively activated recombinant rho protein (Vall4rho) into subconfluent cells induces dra- matic changes in cell morphology: 15-30 min after in- jection cells adopt a distinct and novel

Hugh E Paterson; Annette J. Self; Michelle D. Garrett; Ingo Just

1990-01-01

172

Current Morphologic Criteria Perform Poorly in Identifying Hereditary Leiomyomatosis and Renal Cell Carcinoma Syndrome-associated Uterine Leiomyomas.  

PubMed

The contemporary oncologic pathology report conveys diagnostic, prognostic, predictive, and hereditary predisposition information. Each component may be premised on a morphologic feature or a biomarker. Clinical validity and reproducibility are paramount as is standardization of reporting and clinical response to ensure individualization of patient care. Regarding hereditary predisposition, morphology-based genetic referral systems in some instances have eclipsed genealogy-based systems, for example, cell type in ovarian cancer and BRCA screening. In other instances such as Lynch syndrome, morphology-based schemas supplement clinical schemas and there is an emerging standard of care for reflex biomarker testing. Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) syndrome predisposes patients to uterine and cutaneous leiomyomas (LMs) and renal cell carcinomas (RCCs). Several authors have emphasized the role pathologists may play in identifying this syndrome by recognizing the morphologic characteristics of syndromic uterine LMs and RCCs. Recently immunohistochemical overexpression of S-(2-succinyl) cysteine (2SC) has been demonstrated as a robust biomarker of mutation status in tumors from HLRCC patients. In this blinded control-cohort study we demonstrate that the proposed morphologic criteria used to identify uterine LMs in HLRCC syndrome are largely irreproducible among pathologists and lack sufficient robustness to serve as a trigger to triage cases for 2SC immunohistochemistry or patients for further family/personal history inquiry. Although refinement of morphologic criteria can be considered, in view of the availability of a clinically robust biomarker, consideration should be given to reflex testing of uterine LMs with an appropriate age cut off or in the setting of a suspicious family history. PMID:25272294

Alsolami, Sana; El-Bahrawy, Mona; Kalloger, Steve E; AlDaoud, Nagla; Pathak, Tilak B; Cheung, Catherine T; Mulligan, Anna Marie; Tomlinson, Ian P; Pollard, Patrick J; Gilks, C Blake; McCluggage, W Glenn; Clarke, Blaise A

2014-11-01

173

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. PMID:20559121

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

2010-01-01

174

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. PMID:23555679

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

2013-01-01

175

Morphological, magnetic and electronic structural studies of nanostructured spinel ferrites  

NASA Astrophysics Data System (ADS)

The scope of this thesis includes study of structural, magnetic and electronic properties of nanostructured ferrites with different morphology/geometries (e.g. core/shell and hollow nanoparticles), and non-stroichiomteric thin-films. In the case of core/shell, shell composition is varied and spin glass (SG) features due to the thick amorphous shells are explored. Exchange Bias (EB) for core/shell (ferromagnetic/SG) nanoparticles namely X33Fe 67/XFe67O4 (X = Co, Ni, Fe) is presented. Limitations in the synthesis of various other alloys by inert gas condensation (IGC) due to the difference in the melting points are discussed. The existence of SG phase in these nanoparticles with CoFe2O4 shell results in the enhancement in EB. This is attributed to the large bulk anisotropy constant of the shell compared to other spinel cubic ferrites. Both dc magnetization and ac susceptibility measurements revealed a SG like transition which occurs at unusually large spin freezing temperature (TF ˜ 175K). The SG nature of the transition is also confirmed by the field dependence of the freezing temperature (TF(H)) following the well-known Almeida-Thouless (AT) line, deltaT F ˜ H2/3. Particles exhibit a large exchange bias (HEB ˜ 1357Oe) arising from the core-shell (ferromagnetic-SG) coupling. The unusually high SG transition temperature and large exchange bias effects are attributed to a combination of several factors including the thickness of the amorphous oxide shell and large values of the exchange and anisotropy constants associated with the CoFe2O 4 shell. In another extreme case of disordered spin systems, we synthesized NPs with hollow morphology with intentional choice of material namely NiFe 2O4 (CoFe2O4) which has lowest (highest) bulk anisotropy constant among the spinel ferrites. The hollow NPs are synthesized by self-templating process utilizing coupled interfacial chemical reactions and Kirkendall effect between the core (X33Fe67) and the shell (XFe2O4) of the core/shell structure is described. Reaction temperature and time dependent structural and morphological transformations are presented in detail. NiFe2O4 hollow particles show lack of saturation, enhancement in EB and inverse trend in the blocking temperature as a function of particles size. These are explained as being due to stabilized spin disorder and surface anisotropy. Unlike solid NPs, hollow NPs are polycrystalline. Electronic structure studies are performed by photoemission which reveals that CoFe2O4 particles with hollow morphology have higher degree of inversion compared to solid NPs. Electronic structure in comparison with magnetic studies reveal that particles exhibit uncompensated spins unlike bulk where Neel's collinear spin alignment is expected. For CoFe2O 4, both morphologies show lack of saturation up to 7T of applied field and magnetic irreversibility exists up to 7T of cooling fields for the entire temperature range (10 to 300K). These effects are explained in terms of temperature dependent large bulk anisotropy constant of CoFe2O4. Strong influence of uncompensated spins for particles with hollow morphology is characterized by cooling the sample in large fields, up to (˜9T). Magnitude of horizontal shift is more than three times larger compared to that of particles with solid morphology. 11% vertical shift for particles with hollow morphology is observed, whereas solid particles do not show corresponding shift. Finally, off-stoichiometric NiFe2O4 films prepared by pulsed laser deposition at low pressures and relatively high substrate temperatures were studied. Details of electronic structure of the films are presented and compared with stoichiometric bulk counterpart. Significant amount of oxygen vacancies and enhanced cationic inversion for non-stoichiometric thin films is observed. Films show spin glass features which are contrary to the usual ferrimagnetic response of the bulk nickel ferrite and spin freezing temperature which lies above room temperature in low fields (cooling field ˜ 0.1T). Interestingly, an exceptionally large exchange bi

Jardim, Marcos; Moura Prata, Daniela

176

Temperature dependence of toothbrush bristle morphology. An ultrastructural study.  

PubMed

In this study, it was demonstrated that the original forms of toothbrush bristle ends undergo morphological changes during the preparatory procedures required prior to their examination by scanning electron microscopy (SEM). In particular, the distance of the specimens from the cathode of a traditional sputter-coater and the time of gold-palladium coating influence the temperature inside the vacuum compartment. Moreover, the temperature influences the original morphology of toothbrush bristles. 2 segments of each toothbrush head with nylon or ultralon bristles were cut off the brush: one was mounted vertically and one horizontally on stubs for SEM analysis. Different temperatures were measured inside the sputter-coater at the level of the bristle ends, during coating with gold-palladium alloy. The temperature at the level of the bristles that were placed horizontally was about 38 degrees C, and 59 degrees C when they were placed vertically. SEM analysis of the specimens showed that the same toothbrush has end-rounded bristles at about 59 degrees C and non-acceptable irregular bristles at about 38 degrees C. Retraction of bristles (which appeared shortened and with increased diameters) and superficial cracks were particularly present in the vertically placed ultralon bristles. PMID:8583025

Franchi, M; Checchi, L

1995-08-01

177

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

178

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

PubMed Central

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

2014-01-01

179

Role of laminin and basement membrane in the morphological differentiation of human endothelial cells into capillary-like structures  

Microsoft Academic Search

We have defined a signal responsible for the morphological differentiation of human umbilical vein and human dermal microvascular endothelial cells in vitro. We find that human umbilical vein endothelial cells deprived of growth factors undergo morphologi- cal differentiation with tube formation after 6-12 wk, and that human dermal microvascular endothelial cells differentiate after 1 wk of growth factor deprivation. Here,

Yasuo Kubota; Hynda K. Kleinman; George R. Martin; Thomas J. Lawley

1988-01-01

180

Nodular lymphocyte-predominant hodgkin lymphoma with atypical T cells: a morphologic variant mimicking peripheral T-cell lymphoma.  

PubMed

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a distinct Hodgkin lymphoma subtype composed of few neoplastic lymphocyte-predominant (LP) cells in a background of reactive small B and T cells. We have seen occasional NLPHL cases that contain background T cells with prominent cytologic atypia, raising the differential diagnosis of peripheral T-cell lymphoma not otherwise specified (PTCL-NOS) or a composite lymphoma. We sought to characterize the clinicopathologic features of such cases. Eleven NLPHL cases with atypical T cells diagnosed from 1977 to 2010 were identified at 2 institutions and compared with 24 control NLPHL cases lacking atypical T cells. All 9 male patients and 2 female patients presented with localized peripheral lymphadenopathy. In comparison with control patients, they were younger (median age, 13.8 vs. 36.1 y; P=0.015), with more frequent cervical lymph node involvement (54.5% vs. 8.3%, P=0.015). In all 11 cases, areas of NLPHL with typical B-cell-rich nodules containing LP cells were present. Nine cases contained sheets of atypical T cells surrounding primary and secondary follicles in a pattern mimicking the T-zone pattern of PTCL-NOS; the remaining 2 cases contained atypical T cells presented as large clusters at the periphery of B-cell-rich nodules. In all cases, the atypical T-cell-rich areas contained rare scattered LP cells, which were IgD in 5 of 7 cases (71.4%). The atypical T cells showed no pan-T-cell antigen loss or aberrant T-cell antigen expression in any case, and polymerase chain reaction or Southern blot analysis showed no evidence of T-cell clonality in 6 cases tested. The atypical T cells exhibited a variable immunophenotype with respect to germinal center, follicular T-helper, T-regulatory, and cytotoxic T-cell markers. Among 8 patients with clinical follow-up (median follow-up: 6.4 y), 5 patients had recurrent NLPHL at 6 months to 12 years after diagnosis and 6 patients are alive without disease at 9 months to 18 years after diagnosis. In comparison with control patients, NLPHL patients with atypical T cells were more likely to develop recurrent NLPHL (71.4% vs. 13.6%, P=0.008) and to have a shorter time to relapse (P=0.04). Our findings suggest that some cases of NLPHL, occurring predominantly in younger patients, contain prominent populations of morphologically atypical T cells that may raise the possibility of concurrent nodal involvement by PTCL-NOS, a rare diagnosis in children. The clinical behavior of these cases appears similar to that of NLPHL with T-cell-rich diffuse areas, with a higher risk of disease recurrence and no difference in overall survival; however, this finding warrants confirmation in studies of larger numbers of patients. PMID:21997687

Sohani, Aliyah R; Jaffe, Elaine S; Harris, Nancy Lee; Ferry, Judith A; Pittaluga, Stefania; Hasserjian, Robert P

2011-11-01

181

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

PubMed Central

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

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

2011-01-01

182

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

PubMed

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

Birba, A; Ramallo, M R; Morandini, L; Villafañe, V; Tubert, C; Guimarães Moreira, R; Pandolfi, M

2014-09-01

183

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

SciTech Connect

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

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

2013-06-10

184

Dendritic morphology and tracer-coupling pattern of physiologically identified transient uniformity detector ganglion cells in rabbit retina.  

PubMed

Transient uniformity detectors (UDs) are a unique type of retinal ganglion cell (RGC) whose maintained firing is transiently suppressed by all types of visual stimuli. In this study, we have characterized the dendritic morphology and tracer-coupling pattern of UDs that were labeled by loose-seal electroporation of Neurobiotin following functional identification in the isolated rabbit retina. The UDs have a bistratified dendritic tree, branching near the margins of the inner plexiform layer in stratum 1 (part of the OFF sublamina) and stratum 4/5 (part of the ON sublamina). Characteristically, many of the distal dendrites in the OFF arbor do not terminate there but dive recurrently back to the ON arbor. As a consequence, the ON dendritic arbor is usually twice as large as the OFF dendritic arbor in area. The UDs sometimes show homologous tracer coupling to neighboring RGCs with the same morphology, and from this material, we estimate that the UDs have a threefold dendritic field overlap and a maximum density of ~100 cells/mm2 on the peak visual streak, accounting for ~2% of RGCs in rabbit retina. The UDs also show strong heterologous tracer coupling to a novel type of amacrine cell that costratifies with the ON arbor of the UD. Consistent with their unistratified medium-field morphology, these St4/5 amacrine cells appear to be GABAergic: their somata are immunopositive for GABA but immunonegative for glycine and glycine transporter 1. We compare the dendritic morphology of the UDs to that of other types of bistratified RGCs described in rabbit retina and note that the stratification levels and distinctive recurrent dendrites closely resemble those of the "ON bistratified diving" RGCs. This raises the possibility that there are two types of RGCs with distinctive physiological properties that have almost identical bistratified dendritic morphologies. PMID:20854715

Sivyer, Benjamin; Vaney, David I

2010-11-01

185

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

186

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. PMID:11465866

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

2001-01-01

187

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

PubMed

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

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

2010-05-01

188

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

PubMed Central

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

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

2011-01-01

189

A Morphological Study of Gamma-Ray Burst Host Galaxies  

E-print Network

We present a comprehensive study of the morphological properties of 42 gamma-ray burst (GRB) host galaxies imaged with the Hubble Space Telescope in the optical band. The purpose of this study is to understand the relation of GRBs to their macro-environments, and to compare the GRB-selected galaxies to other high redshift samples. We perform both qualitative and quantitative analyses by categorizing the galaxies according to their visual properties, and by examining their surface brightness profiles. We find that all of the galaxies have approximately exponential profiles, indicative of galactic disks, and have a median scale length of about 1.7 kpc. Inspection of the visual morphologies reveals a high fraction of merging and interacting systems, with \\~30% showing clear signs of interaction, and an additional ~30% exhibiting irregular and asymmetric structure which may be the result of recent mergers; these fractions are independent of redshift and galaxy luminosity. On the other hand, the three GRB host galaxies for which submillimeter and radio emission has been detected are isolated and compact, unlike the luminous submillimeter-selected galaxies. The fraction of mergers appears to be elevated compared to other high redshift samples, particularly for the low luminosities of GRB hosts (M_B ~ -16 to -21 mag). This suggests that merging and interacting galaxies undergoing a burst of star formation may be an efficient site for the production of GRB progenitors. Finally, we show that GRB hosts clearly follow the size-luminosity relation present in other galaxy samples, but thanks to absorption redshifts they help extend this relation to lower luminosities.

C. Wainwright; E. Berger; B. E. Penprase

2005-08-02

190

Transforming growth factor-?2 induces morphological alteration of human corneal endothelial cells in vitro  

PubMed Central

AIM To investigate the morphological altering effect of transforming growth factor-?2 (TGF-?2) on untransfected human corneal endothelial cells (HCECs) in vitro. METHODS After untransfected HCECs were treated with TGF-?2 at different concentrations, the morphology, cytoskeleton distribution, and type IV collagen expression of the cells were examined with inverted contrast light microscopy, fluorescence microscopy, immunofluorescence or Western Blot. RESULTS TGF-?2 at the concentration of 3-15 µg/L had obviously alterative effects on HCECs morphology in dose and time-dependent manner, and 9 µg/L was the peak concentration. TGF-?2 (9 µg/L) altered HCE cell morphology after treatment for 36h, increased the mean optical density (P<0.01) and the length of F-actin, reduced the mean optical density (P<0.01) of the collagen type IV in extracellular matrix (ECM) and induced the rearrangement of F-actin, microtubule in cytoplasm and collagen type IV in ECM after treatment for 72h. CONCLUTION TGF-?2 has obviously alterative effect on the morphology of HCECs from polygonal phenotype to enlarged spindle-shaped phenotype, in dose and time-dependence manner by inducing more, elongation and alignment of F-actin, rearrangement of microtubule and larger spread area of collagen type IV. PMID:25349788

Wang, Jing; Fan, Ting-Jun; Yang, Xiu-Xia; Chang, Shi-Min

2014-01-01

191

Prevalence, morphology, and natural history of FGFR1-amplified lung cancer, including squamous cell carcinoma, detected by FISH and SISH.  

PubMed

The aim of this study was to investigate the prevalence of fibroblast growth factor receptor 1 (FGFR1) amplification by fluorescence in situ hybridization (FISH) in a lung cancer patient cohort and to correlate results with morphology, silver in situ hybridization (SISH), and patient outcome. FGFR1 FISH and SISH were performed in 406 and 385 lung cancer cases, respectively, and the results were compared. High-level FGFR1 amplification was defined as the ratio of FGFR1/centromere 8 ?2, or tumor cell percentage with ?15 signals ?10%, or average number of signals/tumor cell nucleus ?6. Low-level amplification was defined as tumor cell percentage with ?5 signals ?50%. Of 406 tumors tested, there were 191 squamous cell carcinomas, 28 carcinomas with focal squamous morphology, 24 large cell carcinomas with squamous immunoprofile, 115 adenocarcinomas, 17 neuroendocrine tumors, and 31 carcinomas without squamous morphology or immunoprofile. FGFR1 FISH was assessable in 368 tumors, with FGFR1 amplification identified in 50, including 48 tumors with either squamous morphology or immunoprofile (48 of 225, 21.3%), and two 'marker-null' tumors without squamous or glandular morphology or immunoprofile (2 of 143, 1.4%; P<0.0001). FGFR1 SISH was assessable in 347 tumors. All 46 FGFR1 FISH-amplified tumors with tumor available for testing showed amplification with SISH, while all other tumors were negative. There was no relationship between FGFR1 amplification status and disease-free (P=0.88, HR=1.04, 95% confidence interval (CI)=0.67-1.60) or overall survival (P=0.97, HR=1.01, 95% CI=0.65-1.58) in surgically radically treated patients with tumors with any squamous morphology or immunoprofile. FGFR1 amplification is a common abnormality in tumors with any squamous morphology or immunoprofile, but it is also present in 'marker-null' tumors. The results of FGFR1 SISH showed 1:1 correlation with the results of FGFR1 FISH, indicating that SISH may be an alternative method to detect FGFR1 amplification. No relationship was detected between patient outcome and FGFR1 amplification. PMID:24762544

Russell, Prudence A; Yu, Yong; Young, Richard J; Conron, Matthew; Wainer, Zoe; Alam, Naveed; Solomon, Benjamin; Wright, Gavin M

2014-12-01

192

Morphological changes in paraurethral area after introduction of tissue engineering construct on the basis of adipose tissue stromal cells.  

PubMed

We studied morphological changes in the paraurethral area of Wistar rats after introduction of tissue engineering constructs on the basis of multipotent mesenchymal stem cells and gelatin sponge. The tissue engineering construct containing autologous culture of the stromal fraction of the adipose tissue was most effective. After introduction of this construct we observed more rapid degradation of the construct matrix and more intensive formation of collagen fibers. PMID:20396777

Makarov, A V; Arutyunyan, I V; Bol'shakova, G B; Volkov, A V; Gol'dshtein, D V

2009-10-01

193

Carbon Availability Affects Diurnally Controlled Processes and Cell Morphology of Cyanothece 51142  

PubMed Central

Cyanobacteria are oxygenic photoautotrophs notable for their ability to utilize atmospheric CO2 as the major source of carbon. The prospect of using cyanobacteria to convert solar energy and high concentrations of CO2 efficiently into biomass and renewable energy sources has sparked substantial interest in using flue gas from coal-burning power plants as a source of inorganic carbon. However, in order to guide further advances in this area, a better understanding of the metabolic changes that occur under conditions of high CO2 is needed. To determine the effect of high CO2 on cell physiology and growth, we analyzed the global transcriptional changes in the unicellular diazotrophic cyanobacterium Cyanothece 51142 grown in 8% CO2-enriched air. We found a concerted response of genes related to photosynthesis, carbon metabolism, respiration, nitrogen fixation, ribosome biosynthesis, and the synthesis of nucleotides and structural cell wall polysaccharides. The overall response to 8% CO2 in Cyanothece 51142 involves different strategies, to compensate for the high C/N ratio during both phases of the diurnal cycle. Our analyses show that high CO2 conditions trigger the production of carbon-rich compounds and stimulate processes such as respiration and nitrogen fixation. In addition, we observed that high levels of CO2 affect fundamental cellular processes such as cell growth and dramatically alter the intracellular morphology. This study provides novel insights on how diurnal and developmental rhythms are integrated to facilitate adaptation to high CO2 in Cyanothece 51142. PMID:23457634

Stockel, Jana; Elvitigala, Thanura R.; Liberton, Michelle; Pakrasi, Himadri B.

2013-01-01

194

Ethanol interferes with thrombin mediated changes in the morphology and cytoskeleton of human vascular endothelial cells  

SciTech Connect

The effect of physiological concentrations of ethanol (EtOH) on the response of human vascular endothelial cells (EC) to thrombin was examined Treatment of EC with EtOH concentrations of 20-85mM for 2-10 min. produced no significant changes in the morphology of 3- and 4-day monolayers established on fibronectin coated polystyrene. When examined immunofluorescently no significantly changes in the microfilament or microtubule structures were seen. Exposure of EC monolayers to 0.5 and 1 U/ml of thrombin for 1-60 minutes causes a concentration and time dependent monolayer retraction, evidenced by a general decrease in cell size, increase in visible gaps in the monolayer and redistribution of the microtubule and microfilament networks. Pretreatment of EC monolayers with EtOH for 3-5 minutes prior to addition of thrombin prevents the changes seen with thrombin alone. Immunofluorescent examination of the microfilament and microtubule structures suggests than EtOH may act in part via the microtubule network, which appears to be disorganized/disrupted when the EC are exposed to EtOH and then thrombin. Colchicine studies show that EC which have been pretreated with EtOH respond to colchicine differently then cells which have not previously seen EtOH. These data suggest that EtOH may alter EC monolayer responsiveness either by indirect changes which are reflected in cytoskeletal disorganization or possibly by direct influence on the cytoskeleton.

Pratt, K.J.; Rubin, R.; Hoek, J.; Williams, S.K. (Thomas Jefferson Univ., Philadelphia, PA (United States))

1991-03-15

195

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

196

CHEMICAL METHODS vs PHYSICAL METHODS FOR PDVF MORPHOLOGY STUDIES  

Microsoft Academic Search

Morphology of poly(vinylidene fluoride) PDVF is of practical concern, this polymer may be processed to give a number of different crystal forms such as ?, ?, ? and these may exhibit a wide range of different morphologies. Due to the difficulty of the PVDF material presents to be observed by electron microscopy techniques, Vaughan developed a method that implies chemical

C. Urbina de Navarro; N. Díaz; M. Pérez-De

197

ALS/FTLD-linked TDP-43 regulates neurite morphology and cell survival in differentiated neurons  

SciTech Connect

Tar-DNA binding protein of 43 kDa (TDP-43) has been characterized as a major component of protein aggregates in brains with neurodegenerative diseases such as frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). However, physiological roles of TDP-43 and early cellular pathogenic effects caused by disease associated mutations in differentiated neurons are still largely unknown. Here, we investigated the physiological roles of TDP-43 and the effects of missense mutations associated with diseases in differentiated cortical neurons. The reduction of TDP-43 by siRNA increased abnormal neurites and decreased cell viability. ALS/FTLD-associated missense mutant proteins (A315T, Q331K, and M337V) were partially mislocalized to the cytosol and neurites when compared to wild-type and showed abnormal neurites similar to those observed in cases of loss of TDP-43. Interestingly, cytosolic expression of wild-type TDP-43 with mutated nuclear localization signals also induced abnormal neurtie morphology and reduction of cell viability. However, there was no significant difference in the effects of cytosolic expression in neuronal morphology and cell toxicity between wild-type and missense mutant proteins. Thus, our results suggest that mislocalization of missense mutant TDP-43 may contribute to loss of TDP-43 function and affect neuronal morphology, probably via dominant negative action before severe neurodegeneration in differentiated cortical neurons. Highlights: • The function of nuclear TDP-43 in neurite morphology in mature neurons. • Partial mislocalization of TDP-43 missense mutants into cytosol from nucleus. • Abnormal neurite morphology caused by missense mutants of TDP-43. • The effect of cytosolic expression of TDP-43 in neurite morphology and in cell survival.

Han, Jeong-Ho; Yu, Tae-Hoon; Ryu, Hyun-Hee; Jun, Mi-Hee; Ban, Byung-Kwan [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of); Jang, Deok-Jin [Department of Applied Biology, College of Ecology and Environment, Kyungpook National University, 386, Gajang-dong, Sangju-si, Kyungbuk 742-711 (Korea, Republic of); Lee, Jin-A, E-mail: leeja@hnu.kr [Department of Biotechnology, College of Life Science and Nanotechnology, Hannam University, Dajeon 305-811 (Korea, Republic of)

2013-08-01

198

The gastric wall in systemic sclerosis patients: a morphological study.  

PubMed

Organ failure secondary to fibrosis is the main cause of morbidity and death in patients with systemic sclerosis. Gastrointestinal tract dysmotility is a major visceral manifestation, clinically ranging from an asymptomatic form to severe paresis. Although the oesophagus is the most frequently affected part of the gastrointestinal tract, all other segments can be involved. The present study was undertaken to evaluate the histopathological changes of the gastric wall in a series of full-thickness biopsies from systemic sclerosis patients who underwent gastric surgery due to severe gastroesophageal involvement. Gastric biopsies were processed for light microscopy and transmission electron microscopy. The histological and ultrastructural observations revealed a generalized fibrosis affecting all the gastric wall layers. The most severe changes were observed in the muscularis mucosae and muscle layers. Wide areas of marked focal fibrosis with dense collagen bundles and elastic fibre deposition surrounding smooth muscle cells were found. Myofilaments and thickened dense bodies were severely disarranged or absent in most smooth muscle cells. Nerve fibres showed ultrastructural alterations, such as oedematous axoplasm and scarce cytoskeletal elements. Abundant elastic and collagen fibres enveloped nerve fibres, nerve endings and interstitial cells of Cajal, thereby separating them from smooth muscle cells and blood microvessels. This study provides evidence for a prominent fibrosis and severe ultrastructural alterations of smooth muscle cells and nerve fibres as the main histopathological hallmarks in the gastric wall of systemic sclerosis patients. PMID:21073000

Manetti, Mirko; Milia, Anna Franca; Benelli, Gemma; Messerini, Luca; Matucci-Cerinic, Marco; Ibba-Manneschi, Lidia

2010-01-01

199

Morphological factors as indicators of malignancy of squamous cell carcinomas in cattle exposed naturally to bracken fern (Pteridium aquilinum).  

PubMed

Squamous cell carcinomas (SCCs) of the upper digestive tract (UDT) of cattle have been associated with chronic bracken fern (Pteridium aquilinum) toxicity and infection with bovine papillomavirus type-4. These tumours share some morphological similarities with human head and neck SCCs. In this study, morphological changes were correlated with the biological behaviour of 40 alimentary SCCs in cattle grazing on pastures with high bracken content. The majority of SCCs were localized to the cranial and caudal regions of the UDT (almost 45% each). More than 60% of the tumours were well differentiated and were found mostly in the cranial region. Metastasis occurred in 58% of the cases, mostly to regional lymph nodes. All poorly differentiated SCCs had evidence of metastasis. Morphological patterns characterized by islands and ribbons of neoplastic keratinocytes were more prominent in well differentiated SCCs. These patterns varied greatly in moderately differentiated SCCs. Poorly differentiated tumours were characterized by the presence of cellular aggregates and individual cells and these tumours had more marked desmoplasia. A significant positive association was established between lymphoplasmacytic inflammatory infiltration and tumour-associated tissue eosinophilia. Evaluation of argyrophylic nucleolar organizer regions (AgNORs) revealed higher proliferation indices in poorly differentiated tumours than in moderately or well differentiated lesions. There was significant correlation between the AgNOR index and histological grading. The morphological factors analyzed were all related to histological grading, which is the major factor predicting the biological behaviour of SCCs in cattle naturally exposed to bracken fern. PMID:20542519

Masuda, E K; Kommers, G D; Martins, T B; Barros, C S L; Piazer, J V M

2011-01-01

200

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

201

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

ERIC Educational Resources Information Center

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

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

2011-01-01

202

Comparative studies of follicle cells in testes of Glyptocephalus stelleri and Pleuronectes pinnifasciatus (teleostei, pleuronectidae)  

Microsoft Academic Search

Accessory cells were studied in early spermatogenesis of flatfishes Glyptocephalus stelleri and Pleuronectes pinnifasciatus using transmission electron microscopy. The morphological organization of accessory cells in G. stelleri was similar to that of Sertoli cells. In P. pinnifasciatus, these cells had morphological organization, which had not been previously described.

S. Yu. Neznanova; V. N. Ivankov; A. A. Reunov

2005-01-01

203

[Comparative studies of follicle cells in testes of Glyptocephalus stelleri and Pleuronectes pinnifasciatus (Teleostei, Pleuronectidae)].  

PubMed

Accessory cells were studied in early spermatogenesis of flatfishes Glyptocephalus stelleri and Pleuronectes pinnifasciatus using transmission electron microscopy. The morphological organization of accessory cells in G. stelleri was similar to that of Sertoli cells. In P. pinnifasciatus, these cells had morphological organization, which had not been previously described. PMID:15807438

Neznanova, S Iu; Ivankov, V N; Reunov, A A

2005-01-01

204

EFFECTS OF VISUAL DEPRIVATION ON MORPHOLOGY AND PHYSIOLOGY OF CELLS IN THE CAT'S  

E-print Network

system this problem has usually been approached by examining the effects of sensory deprivationEFFECTS OF VISUAL DEPRIVATION ON MORPHOLOGY AND PHYSIOLOGY OF CELLS IN THE CAT'S LATERAL GENICULATE would be to examine electrophysiologically the functional effects of visual deprivation

Hubel, David

205

Morphological stability of organic solar cells based upon an oligo(p-phenylenevinylene)-C70 dyad.  

PubMed

An oligo(p-phenylenevinylene)-C(70) dyad achieves the highest power conversion efficiency (1.92%) in dyad-based organic solar cells to date. Covalent attachment in the dyad prevents large phase separation, resulting in good morphological and device stability at high temperatures as compared with mixed bulk heterojunction devices. PMID:23108576

Izawa, Seiichiro; Hashimoto, Kazuhito; Tajima, Keisuke

2012-12-14

206

Exploring Wavelet Transforms for Morphological Differentiation Between Functionally Different Cat Retinal Ganglion Cells  

Microsoft Academic Search

Cognition or higher brain activity is sometimes seen as a phenomenon greater than the sum of its parts. This viewpoint however is largely dependent on the state of the art of experimental techniques that endeavor to characterize morphology and its association to function. Retinal ganglion cells are readily accessible for this work and we discuss recent advances in computational techniques

H. F. JELINEK; R. M. CESAR; J. J. G. LEANDRO

2003-01-01

207

Thermal stabilisation of polymer-fullerene bulk heterojunction morphology for efficient photovoltaic solar cells.  

PubMed

A novel stable bisazide molecule that can freeze the bulk heterojunction morphology at its optimized layout by specifically bonding to fullerenes is reported. The concept is demonstrated with various polymers: fullerene derivatives systems enable highly thermally stable polymer solar cells. PMID:25042898

Derue, Lionel; Dautel, Olivier; Tournebize, Aurélien; Drees, Martin; Pan, Hualong; Berthumeyrie, Sébastien; Pavageau, Bertrand; Cloutet, Eric; Chambon, Sylvain; Hirsch, Lionel; Rivaton, Agnès; Hudhomme, Piétrick; Facchetti, Antonio; Wantz, Guillaume

2014-09-01

208

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

209

In vitro cultivation of human tumor tissues. II. Morphological and virological characterization of three cell lines.  

PubMed

Nineteen human tumors, mostly of sarcomatous nature, were cultured in vitro. Three cell lines were isolated and further characterized: MG-57 derived from a giant cell tumor, MG-63 derived from an osteosarcoma and MG-72 derived from a xanthohistiocytoma. The cell lines varied in morphology and growth pattern. An abnormal karyotype with marker chromosomes was present in Mg-63 and MG-72. None of the cell lines spontaneously produced detectable C-type virus particles. Stimulation with IUDR and dexamethasone also failed to induce detectable particle release. PMID:218153

Heremans, H; Billiau, A; Cassiman, J J; Mulier, J C; de Somer, P

1978-01-01

210

Liver-cell patterning lab chip: mimicking the morphology of liver lobule tissue.  

PubMed

A lobule-mimetic cell-patterning technique for on-chip reconstruction of centimetre-scale liver tissue of heterogeneous hepatic and endothelial cells via an enhanced field-induced dielectrophoresis (DEP) trap is demonstrated and reported. By mimicking the basic morphology of liver tissue, the classic hepatic lobule, the lobule-mimetic-stellate-electrodes array was designed for cell patterning. Through DEP manipulation, well-defined and enhanced spatial electric field gradients were created for in-parallel manipulation of massive individual cells. With this liver-cell patterning labchip design, the original randomly distributed hepatic and endothelial cells inside the microfluidic chamber can be manipulated separately and aligned into the desired pattern that mimicks the morphology of liver lobule tissue. Experimental results showed that both hepatic and endothelial cells were orderly guided, snared, and aligned along the field-induced orientation to form the lobule-mimetic pattern. About 95% cell viability of hepatic and endothelial cells was also observed after cell-patterning demonstration via a fluorescent assay technique. The liver function of CYP450-1A1 enzyme activity showed an 80% enhancement for our engineered liver tissue (HepG2+HUVECs) compared to the non-patterned pure HepG2 for two-day culturing. PMID:23743812

Ho, Chen-Ta; Lin, Ruei-Zeng; Chen, Rong-Jhe; Chin, Chung-Kuang; Gong, Song-En; Chang, Hwan-You; Peng, Hwei-Ling; Hsu, Long; Yew, Tri-Rung; Chang, Shau-Feng; Liu, Cheng-Hsien

2013-09-21

211

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

212

Effect of Cytochalasins on F-Actin and Morphology of Ehrlich Ascites Tumor Cells  

Microsoft Academic Search

Cytochalasins have been used extensively to probe the role of F-actin in different aspects of cellular function. Most of the data obtained are interpreted on the basis of the well-established depolymerizing effects of cytochalasins on F-actin preparations in vitro. However, some evidence indicates that, in intact cells, different cytochalasins can have varying effects on cell morphology and F-actin content and

John W. Mills; Stine Falsig Pedersen; Peter S. Walmod; Else K. Hoffmann

2000-01-01

213

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

PubMed Central

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

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

2014-01-01

214

Morphologic Study of Homograft Valves before and after Cryopreservation and after Short-Term Implantation in Patients  

Microsoft Academic Search

Cryopreserved heart valve homografts have been implanted in patients for the past 15 years, but controversies still exist on the survival of donor cells, matrix maintenance, and possible rejection by the host. Therefore a full morphologic study (histology, immunohistochemistry, transmission electron microscopy, and cuprolinic blue-TEM for glycosaminoglycans [GAG]) of short-term implanted uninfected grafts was done using unimplanted valves as the

1997-01-01

215

[Morphologic features of the binucleated lymphocytes for the assesment of persistent B-cell polyclonal lymphocytosis].  

PubMed

Observation of binucleated lymphocytes on a blood film is a cornerstone event to assess persistent polyclonal B-cell lymphocytosis diagnosis (PPBL). But seldom case reports mentioned their finding in other contexts, mainly B-cell lymphoproliferative neoplasms such chronic lymphocytic leukemia or in reactive circumstances as multiple sclerosis undergoing natalizumab treatment. We aimed to check if some particular morphologic features were more specificaly linked to PPBL, reviewing blood films of series of patients affected by PPBL or harbouring binucleated lymphocytes whatever the diagnosis was. We found that binucleated cells in PPBL were heterogeneous but mostly midde-sized cells, asymetricaly bilobed with nucleoli, and with a moderately basophilic cytoplasm. Though mainly observed in PPBL patients, all that criteria remained unspecific. Conversely, the morphologic features of the other lymphoid cells were of good clinical value to affirm PPBL, either monocytoid or hyperbasophilic cells being systematically found. We think that a substantial percentage of binucleated lymphocytes, harbouring morphologic features such as described, and in a context of monocytoid and/or hyperbasophilic lymphocytes is predictive of PPBL diagnosis. PMID:24342786

Lesesve, Jean-François; Gressot, Anne-Lise; Cornet, Edouard; Mossafa, Hossein; Troussard, Xavier

2013-01-01

216

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

PubMed Central

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

2014-01-01

217

Cellular Differentiation in Moss Protonemata: A Morphological and Experimental Study  

PubMed Central

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

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

2008-01-01

218

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

219

Morphological and microstructural studies on aluminizing coating of carbon steel  

SciTech Connect

Hot dip aluminizing is one of the most effective methods of surface protection for steels and is gradually gaining popularity. The morphology and microstructure of an inter-metallic layer form on the surface of low carbon steel by hot dip aluminization treatment had been studied in detail. This effect has been investigated using optical and scanning electron microscopy, and X-ray diffraction. The result shows that the reaction between the steel and the molten aluminium leads to the formation of Fe–Al inter-metallic compounds on the steel surface. X-ray diffraction and electron microscopic studies showed that a two layer coating was formed consisting of an external Al layer and a (Fe{sub 2}Al{sub 5}) inter metallic on top of the substrate after hot dip aluminizing process. The inter-metallic layer is ‘thick’ and exhibits a finger-like growth into the steel. Microhardness testing shown that the intermetallic layer has high hardness followed by steel substrate and the lowest hardness was Al layer.

Samsu, Zaifol; Othman, Norinsan Kamil; Daud, Abd Razak; Hussein, Hishammuddin [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2013-11-27

220

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

PubMed

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

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

2013-08-01

221

Serine palmitoyltransferase subunit 1 is present in the endoplasmic reticulum, nucleus and focal adhesions, and functions in cell morphology  

PubMed Central

Serine palmitoyltransferase (SPT) has been localized to the endoplasmic reticulum (ER) by subcellular fractionation and enzymatic assays, and fluorescence microscopy of epitope-tagged SPT; however, our studies have suggested that SPT subunit 1 might be present also in focal adhesions and the nucleus. These additional locations have been confirmed by confocal microscopy using HEK293 and HeLa cells, and for focal adhesions by the demonstration that SPT1 co-immunoprecipitates with vinculin, a focal adhesion marker protein. The focal adhesion localization of SPT1 is associated with cell morphology, and possibly cell migration, because it is seen in most cells before they reach confluence but disappears when then become confluent, and is restored by a standard scratch-wound healing assay. Conversely, elimination of SPT1 using SPTLC1 siRNA causes cell rounding. Thus, in addition to its “traditional” localization in the ER for de novo sphingolipid biosynthesis, SPT1 is present in other cellular compartments, including focal adhesions where it is associated with cell morphology. PMID:19362163

Wei, Jia; Yerokun, Tokunbo; Leipelt, Martina; Haynes, Chris A.; Radhakrishna, Harish; Momin, Amin; Kelly, Samuel; Park, Hyejung; Wang, Elaine; Carton, Jill M.; Uhlinger, David J.; Merrill, Alfred H.

2009-01-01

222

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

PubMed

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

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

2014-11-21

223

Activin B Antagonizes RhoA Signaling to Stimulate Mesenchymal Morphology and Invasiveness of Clear Cell Renal Cell Carcinomas  

PubMed Central

Activin B belongs to the TGF? family of growth factors and is upregulated in clear cell renal cell carcinoma cells by hypoxia inducible factors. Expression of Activin B is required for tumor growth in vivo and tumor cell invasion in vitro. Here we show that activation of RhoA signaling counteracts Activin B mediated disassembly of actin stress fibers, mesenchymal cell morphology and invasiveness, whereas inhibition of RhoA rescues these effects in Activin B knockdown cells. Conversely, Activin B inhibits RhoA signaling suggesting that there is an antagonistic connection between both pathways. In addition we found that Rac1 plays an opposite role to RhoA, i.e. activation of Rac1 initiates loss of actin stress fibers, promotes a mesenchymal cell morphology and induces invasion in Activin B knockown cells, whereas inhibition of Rac1 abolishes these Activin B effects. Collectively, our data provide evidence that reduction of RhoA signaling by Activin B together with persistent Rac1 activity is a prerequisite for inducing an invasive phenotype in clear cell renal cell carcinoma. PMID:25343250

Wacker, Ingrid; Behrens, Jurgen

2014-01-01

224

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

225

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. PMID:23754988

Warren, Susan; May, Paul J.

2013-01-01

226

CN MORPHOLOGY STUDIES OF COMET 103P/HARTLEY 2  

SciTech Connect

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

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

2011-06-15

227

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

PubMed

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

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

2014-10-01

228

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

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

229

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. PMID:21217828

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

2010-01-01

230

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. PMID:23272044

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

2012-01-01

231

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

PubMed

Retinal degeneration describes a group of disorders which lead to progressive photoreceptor cell death, resulting in blindness. As this occurs, retinal ganglion cells (RGCs) begin to develop oscillatory physiological activity. Here we studied the morphological and physiological properties of RGCs in rd1 mice, aged 30-60 days, to determine how this aberrant activity correlates with morphology. Patch-clamp recordings of excitatory and inhibitory currents were performed, then dendritic structures were visualized by infusion of fluorescent dye. Only RGCs with oscillatory activity were selected for further analysis. Oscillatory frequency and power were calculated using power spectral density analysis of recorded currents. Dendritic arbor stratification, total length, and area were measured from confocal microscope image stacks. These measurements were used to sort RGCs by cluster analysis using Ward's Method. This resulted in a total of 10 clusters, with monostratified and bistratified cells having five clusters each. Both populations exhibited correlations between arbor stratification and aberrant inhibitory input, while excitatory input did not vary with arbor distribution. These findings illustrate the relationship between aberrant activity and RGC morphology at early stages of retinal degeneration. J. Comp. Neurol. 522:4085-4099, 2014. © 2014 Wiley Periodicals, Inc. PMID:25099614

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

2014-12-15

232

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

233

Morphological Transformations in Polymer Brushes in Binary Mixtures: DPD Study.  

PubMed

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

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

2014-11-01

234

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

235

Morphological Study of the Newly Designed Cementless Femoral Stem  

PubMed Central

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

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

2014-01-01

236

Mouse type I IFN-producing cells are immature APCs with plasmacytoid morphology  

Microsoft Academic Search

We show here that mouse interferon-? (IFN-?)–producing cells (mIPCs) are a unique subset of immature antigen-presenting cells (APCs) that secrete IFN-? upon stimulation with viruses. mIPCs have a plasmacytoid morphology, can be stained with an antibody to Ly6G and Ly6C (anti-Ly6G\\/C) and are Ly6C+B220+CD11cloCD4+; unlike other dendritic cell subsets, however, they do not express CD8? or CD11b. Although mIPCs undergo

Carine Asselin-Paturel; Andre Boonstra; Marc Dalod; Isabelle Durand; Nadia Yessaad; Colette Dezutter-Dambuyant; Alain Vicari; Anne O'Garra; Christine Biron; Francine Brière; Giorgio Trinchieri

2001-01-01

237

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

SciTech Connect

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

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

1997-11-01

238

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

PubMed Central

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

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

2014-01-01

239

Abnormal morphology of Bacillus subtilis ugtP mutant cells lacking glucolipids.  

PubMed

Bacillus subtilis Marburg 168 cells with disrupted ugtP, which encodes UDP-glucosyltransferase involved in glucolipid synthesis, were bent and distended. In the ugtP mutant cells, the extracytoplasmic function sigmas SigM, SigV and SigX, were found to be activated. Introduction of a disrupted allele of sigM into the ugtP strain caused even more abnormal morphology, with cells taking on a balloon-like shape; growth of these cells in LB medium was hampered by addition of 1.5% NaCl. Addition of MgSO4 or MnCl2 suppressed the abnormal morphology. In ugtP mutant cells the transcription of the mreB operon from an upstream promoter in maf (designated Pupstream mreB) and PmreBH was 4.3- and 2.3-fold higher, respectively, and localization of GFP-MreB was not in discrete dots (in an apparently helical pattern), but faint and in irregular clusters. GFP-MreB protein was reduced in the ugtP mutant cells. We suggest that glucolipids are important for MreB isoforms to take on the configuration that appears as discrete dots and plays a role in shaping cells into straight rods. PMID:22362028

Matsuoka, Satoshi; Chiba, Minako; Tanimura, Yu; Hashimoto, Michihiro; Hara, Hiroshi; Matsumoto, Kouji

2011-01-01

240

Caudal neurosecretory system synaptic morphology following deafferentation: an electron microscopic degeneration study.  

PubMed

The caudal neurosecretory system of Poecilia sphenops (molly) is an isolated population of neurosecretory cells located in the caudal most aspect of the teleost spinal cord. The structure of this neuroendocrine system is favorable for studies on the synaptic control of neurosecretory mechanisms. Little is known about the detailed synaptology of the system. Morphological and electrophysiological reports have shown that the caudal neurosecretory system is linked to higher brain centers by descending spinal projections. To examine the synaptology of the descending synaptic input, surgical deafferentation was performed by microsuction removal of a segment of spinal cord rostral to the caudal system. The degeneration of axon terminals was studied at various times following deafferentation and compared to control synaptology. Based on vesicle content and morphology, three axon terminal types were found in the caudal neurosecretory system. These terminals formed axosomatic, axodendritic, and axoaxonic synaptic contacts. Following deafferentation, axon terminals with dense-cored vesicles and boutons with round clear vesicles degenerated as evidenced by the electron dense dark reaction and the electron lucent reaction respectively. This suggested that at least two different types of axon terminals arise from the descending projection to the caudal neurosecretory system and that two different neurotransmitters may be influencing the neurosecretory activity of these cells. PMID:6824970

O'Brien, J P; Kriebel, R M

1983-01-01

241

Morphological and morphometric study of the pecten oculi in the budgerigar (Melopsittacus undulatus).  

PubMed

The pecten oculi is a highly vascular and pigmented organ placed in the vitreous body of the avian eye. As no data are currently available on the morphological organization of the pecten in the Psittaciformes, the pecten oculi of the budgerigar (Melopsittacus undulatus) was studied. The eyes from adult male budgerigars were examined by light, transmission, and scanning electron microscopy and a morphometric study on both light and transmission electron microscopy specimens was also performed in the different parts of the organ. In the budgerigar, the type of the pecten oculi was pleated. Its basal part had a cranio-caudal and postero-anterior course; its body consisted of 10-12-folds joined apically by a densely pigmented bridge. The pecten showed many capillaries, whose wall was thick and formed by pericytes and endothelial cells. These latter had a large number of microfolds, rectilinear on their luminal surface and tortuous on their abluminal surface. Interstitial pigment cells were placed among the capillaries, filled with melanin granules and showed many cytoplasmic processes. The morphometric analysis demonstrated significant differences among the three parts of the organ relative to the length of the endothelial processes and to the number and size of the pigment granules. The morphological and morphometric analysis showed that the bridge of the budgerigar, different from the other birds, had a large number of capillaries, so that this part of the organ could also play a trophic role for the retina in addition to the choriocapillaris. PMID:22266789

Micali, Antonio; Pisani, Antonina; Ventrici, Claudia; Puzzolo, Domenico; Roszkowska, Anna Maria; Spinella, Rosaria; Aragona, Pasquale

2012-03-01

242

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

PubMed

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

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

2014-09-01

243

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

PubMed

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 fragments of light yellow cell peptide I. One large cluster of light yellow cells was observed in the ventro-lateral protrusion of the right parietal ganglion, smaller clusters lying in the posterior dorsal part of this ganglion and in the visceral ganglion. The cells had an extended central neurohaemal area. Immunopositive axons projected into all nerves of the ganglia of the visceral complex, into the superior cervical and the nuchal nerves, and into the connective tissue surrounding the central nervous system. Axon tracts ramified between the muscle cells of the walls of the anterior aorta and of smaller blood vessels. Peripheral innervation by the light yellow cell system was only found in muscular tissue of the ureter papilla. The antisera to the two peptide fragments of light yellow cell peptide I not only stained the light yellow cells, but also the identified yellow cells, which have previously been shown to produce the sodium influx-stimulating neuropeptide. The latter cells were negative to the in situ hybridization probes and antisera specific to the light yellow cell system. It is therefore unlikely that the yellow cells express the light yellow cell neuropeptide gene. Nevertheless, the cells contain a neuropeptide sharing antigenic determinants with light yellow cell peptide I.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8111842

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

1994-02-01

244

Surface modification of poly( l -lactic acid) affects initial cell attachment, cell morphology, and cell growth  

Microsoft Academic Search

The object of this study was to develop a highly porous scaffold to be used in regeneration of blood vessels, nerves, and other hollow tissues with small openings. Using the phase-inversion method and a mixture of water and methanol as a coagulating agent, we prepared highly porous flat membranes from poly(l-lactic acid) (PLLA) with numerous pores both on the surface

Manae Yamaguchi; Toshio Shinbo; Toshiyuki Kanamori; Pi-chao Wang; Motohiro Niwa; Hiroyoshi Kawakami; Shoji Nagaoka; Kohichiro Hirakawa; Masahiro Kamiya

2004-01-01

245

Morphological characterization of testicular cells, spermatogenesis and formation of spermatophores in a fish ectoparasite Argulus bengalensis Ramakrishna, 1951 (Crustacea: Branchiura).  

PubMed

The present study has been carried out to describe the cell morphology of the developing male gametes in a fish ectoparasite, Argulus bengalensis Ramakrishna, 1951. With respect to cell volume and nucleoplasmic index, spermatogonia are the smallest and primary spermatocytes are the largest in this lineage. The spermatogonia and the differentiating spermatogenic cells are in separate niches and confined to different enclaves within each testicular lobe. Spermiogenesis occurs within the inner enclave of each testicular lobe. During this process the nucleus becomes streamlined; an acrosome is formed, axoneme is originated, and residual cytoplasm is discarded through the flagellum. The sperm cell morphology displays a general pattern comprising head, mid-piece, and a full length flagellum. In the axoneme 9+2 arrangement of the microtubule is conserved. In addition to the axoneme, some more singlet microtubules are found surrounding a fiber sheath and around one of the mitochondria adjacent to the axoneme. This arrangement indicates a close phylogenetic relationship with pentastomida. In the present study, structure and formation of spermatophore are described in this branchiuran parasite. PMID:24355128

Banerjee, Anirban; Manna, Subha; Saha, Samar Kumar

2014-02-01

246

Effects of Asiasari radix on the morphology and viability of mesenchymal stem cells derived from the gingiva.  

PubMed

Medicinal herbs used in traditional Oriental medicine, which have been in use clinically for thousands of years, are attractive sources of novel therapeutics or preventatives. Asiasari radix (A. radix) has been suggested for use in the treatment of dental diseases, including toothache and aphthous stomatitis. The aim of this study was to evaluate the effects of A. radix extracts on the morphology and viability of human stem cells derived from the gingiva. An Asiasarum heterotropoides extract was centrifuged and freeze-dried in a lyophilizer. Stem cells derived from the gingiva were grown in the presence of A. radix at concentrations ranging between 0.1 µg/ml and 1 mg/ml (0, 0.1, 1, 10, 100 and 1,000 µg/ml). Cell morphology was evaluated with an optical microscope and the viability of the cells was quantitatively analyzed with a cell counting kit-8 (CCK-8) assay for up to seven days. The untreated control group exhibited normal fibroblast morphology. The shapes of the cells following 0.1, 1, 10 and 100 µg/ml A. radix treatments were similar to those of the control group. However, a significant change was noted in the 1,000 µg/ml group on day 1, when compared with the untreated group. Furthermore, on day 7, the shapes of the cells following 100 and 1,000 µg/ml A. radix treatments were rounder and fewer cells were present, when compared with those of the control group. The cultures that grew in the presence of A. radix did not exhibit any changes in the CCK?8 assay on day 2; however, significant reductions in cell viability were noticed following 100 and 1,000 µg/ml A. radix treatment on days 5 and 7. Within the limits of this study, A. radix influenced the viability of the stem cells derived from the gingiva. Thus, the direct application of A. radix to oral tissues may produce adverse effects at high doses. Therefore, the concentration and application time of A. radix requires meticulous control to obtain optimal results. These effects require consideration, if the use of A. radix is planned for the treatment of dental diseases. PMID:25310251

Jeong, Su-Hyeon; Lee, Ji-Eun; Jin, Seong-Ho; Ko, Youngkyung; Park, Jun-Beom

2014-12-01

247

Morphologically Cryptic Species Confound Ecological Studies of the Caddisfly Genus Gumaga (Trichoptera: Sericostomatidae) in Northern California  

Microsoft Academic Search

Two species in the caddisfly genus Gumaga (Sericostomatidae) are currently recognized in North America: Gumaga nigricula (McLachlan, 1871) and Gumaga griseola (McLachlan, 1871). Ecological and morphological studies over the last 20 years indicated that both species were either extremely variable or that morphologically cryptic species were unknowingly being included in the studies. The study reported here examined whether genetic characters

John K. Jackson; Vincent H. Resh

1998-01-01

248

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

PubMed

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

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

2014-01-01

249

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

PubMed Central

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

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

2014-01-01

250

The Latin-Greek Connection: Building Vocabulary through Morphological Study  

ERIC Educational Resources Information Center

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

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

2011-01-01

251

Emergence of Large-Scale Cell Morphology and Movement from Local Actin Filament Growth Dynamics  

Microsoft Academic Search

Variations in cell migration and morphology are consequences of changes in underlying cytoskeletal organization and dynamics. We investigated how these large-scale cellular events emerge as direct consequences of small-scale cytoskeletal molecular activities. Because the properties of the actin cytoskeleton can be modulated by actin- remodeling proteins, we quantitatively examined how one such family of proteins, enabled\\/vasodilator-stimulated phosphoprotein (Ena\\/VASP), affects the

Catherine I. Lacayo; Zachary Pincus; Martijn M. VanDuijn; Cyrus A. Wilson; Daniel A. Fletcher; Frank B. Gertler; Alex Mogilner; Julie A. Theriot

2007-01-01

252

The effect of poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity  

Microsoft Academic Search

The aim of this work was to investigate the effect of triblock copolymer poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity. Docetaxel-loaded nanoparticles were prepared by oil-in-water emulsion\\/solvent evaporation technique using biodegradable poly(lactic-co-glycolic acid) (PLGA) with or without addition of poloxamer 188, respectively. The resulting nanoparticles were found to be spherical with a rough and porous surface.

Fei Yan; Chao Zhang; Yi Zheng; Lin Mei; Lina Tang; Cunxian Song; Hongfan Sun; Laiqiang Huang

2010-01-01

253

Papillary cystadenoma of the epididymis and broad ligament: morphologic and immunohistochemical overlap with clear cell papillary renal cell carcinoma.  

PubMed

Papillary cystadenoma is an uncommon epithelial tumor, originating within the head of the epididymis and broad ligament. When the lesion is bilateral, it is associated with von Hippel-Lindau disease. Its resemblance to metastatic clear cell renal cell carcinoma (RCC) has been noted in the literature. Owing to the emergence of additional markers for RCCs, we have evaluated the immunohistochemical staining patterns of a series of 7 papillary cystadenomas using CK7, RCC, PAX8, carbonic anhydrase IX, and AMACR. Six of the cases involved the epididymis, and 1 involved the broad ligament. The patients ranged in age from 20 to 65 years old. All of the tumors were unilateral and not known to be associated with von Hippel-Lindau disease. The lesions were composed of cystic structures, which focally contained papillary fibrovascular cores lined by cuboidal to columnar bland-appearing cells with clear cytoplasm. Another component was the presence of tubules, which focally had elongated profiles. Reverse polarity, wherein the nuclei are oriented toward the luminal surface with subnuclear vacuoles, was present focally in 4 cases and more extensively in a fifth case. Features associated with malignancy, such as mitotic figures, nuclear pleomorphism, and necrosis, were not identified. All lesions were strongly positive for CK7 and negative for RCC. Carbonic anhydrase IX was positive in all tumors (diffusely positive in 6, patchy in 1) with lack of staining in the apical portion of the cytoplasm (ie, cup-shaped staining). PAX8 showed diffuse positivity in 6 of the 7 lesions, with one of the epididymal cases showing negative staining. AMACR staining was negative in 5 of the 7 cases and showed only focal, weak staining in the remaining 2 cases. The current study more specifically demonstrated that papillary cystadenoma does not resemble clear cell RCC. Rather, papillary cystadenomas of the epididymis and broad ligament have identical morphology and immunohistochemical staining to clear cell papillary RCC. The diagnosis of papillary cystadenoma can be established as clear cell papillary RCC to date has not exhibited metastatic behavior. PMID:24441657

Cox, Roni; Vang, Russell; Epstein, Jonathan I

2014-05-01

254

Morphological features of microglial cells in the hippocampal dentate gyrus of Gunn rat: a possible schizophrenia animal model  

PubMed Central

Background Schizophrenia is a debilitating and complex mental disorder whose exact etiology remains unknown. There is growing amount of evidence of a relationship between neuroinflammation, as demonstrated by microglial activation, and schizophrenia. Our previous studies have proposed that hyperbilirubinemia plays a role in the pathophysiology of schizophrenia. Furthermore, we suggested the Gunn rat, an animal model of bilirubin encephalopathy, as a possible animal model of schizophrenia. However, the effects of unconjugated bilirubin on microglia, the resident immune cell of the CNS, in Gunn rats have never been investigated. In the present study, we examined how microglial cells respond to bilirubin toxicity in adult Gunn rats. Methods Using immunohistochemical techniques, we compared the distribution, morphology, and ultrastructural features of microglial cells in Gunn rats with Wistar rats as a normal control. We also determined the ratio of activated and resting microglia and observed microglia-neuron interactions. We characterized the microglial cells in the hippocampal dentate gyrus. Results We found that microglial cells showed activated morphology in the hilus, subgranular zone, and granular layer of the Gunn rat hippocampal dentate gyrus. There was no significant difference between cell numbers between in Gunn rats and controls. However, there was significant difference in the area of CD11b expression in the hippocampal dentate gyrus. Ultrastructurally, microglial cells often contained rich enlarged rich organelles in the cytoplasm and showed some phagocytic function. Conclusions We propose that activation of microglia could be an important causal factor of the behavioral abnormalities and neuropathological changes in Gunn rats. These findings may provide basic information for further assessment of the Gunn rat as an animal model of schizophrenia. PMID:22424389

2012-01-01

255

THE K-REGION DIHYDRODIOL OF BENZO[A]PYRENE INDUCES DNA DAMAGE AND MORPHOLOGICAL CELL TRANSFORMATION IN C3H10T1/2CL8 MOUSE EMBRYO CELLS WITHOUT THE FORMATION OF DETECTABLE STABLE COVALENT DNA ADDUCTS  

EPA Science Inventory

The K -region dihydrodiol ofbenzo[ a ]pyrene induces DNA damage and morphological cell transformation in C3HlOTY2CL8 mouse embryo cells without the formation of detectable stable covalent DNA adducts Benzo[ a ]pyrene (B[ a ]P) is the most thoroughly studied polycyclic aro...

256

LASER CONFOCAL MICROSCOPY AND GEOGRAPHIC INFORMATION SYSTEMS IN THE STUDY OF DENTAL MORPHOLOGY  

E-print Network

tooth crown morphology of small teeth with almost no loss of shape information. Epoxy resin castsLASER CONFOCAL MICROSCOPY AND GEOGRAPHIC INFORMATION SYSTEMS IN THE STUDY OF DENTAL MORPHOLOGY from teeth. The choice of landmarks, however, may limit the scope of a study as decisions on data

Jernvall, Jukka

257

CHEMICAL AND MORPHOLOGICAL STUDIES OF BACTERIAL SPORE FORMATION  

E-print Network

From the stage of a completed membranous forespore to that of a fully ripened free spore, synchronously sporulating cells of a variant Bacillus cereus were studied by cytological and chemical methods. Particular attention was paid to the development of the three spore layers--cortex, coat, and exosporium--in relation to the forespore membrane. First, the cortex is laid down between the recently described (5) double layers of the forespore membrane. Then when the cortex is 1/ ~ fully formed, the spore coat and exosporium are laid down peripheral to the outer membrane layer covering the cortex. As these latter layers appear, the spores, previously dense by dark phase contrast, gradually "whiten " or show an increase in refractive index. With this whitening, calcium uptake commences, closely followed by the synthesis of dipicolinic acid and the process is terminated, an hour later, with the formation of a fully refractile spore. In calcium-deficient media, final refractility is lessened and dipicolinic acid is formed only in amounts proportional to the available calcium. If calcium is withheld during the period of uptake beyond a critical point, sporulating cells lose the ability to assimilate calcium and to form normal amounts of dipicolinic acid. The resulting deficient spores are liberated from the sporangia but are unstable in water suspensions. Unlike ripe spores, they do not react violently to acid hydrolysis and, in thin sections, their cytoplasmic granules continue to stain with lead solutions.

unknown authors

258

Correlations between the Dielectric Properties and Exterior Morphology of Cells Revealed by Dielectrophoretic Field-Flow Fractionation  

PubMed Central

Although dielectrophoresis (DEP) has great potential for addressing clinical cell isolation problems based on cell dielectric differences, a biological basis for predicting the DEP behavior of cells has been lacking. Here, the dielectric properties of the NCI-60 panel of tumor cell types have been measured by dielectrophoretic (DEP) field-flow fractionation, correlated with the exterior morphologies of the cells during growth, and compared with the dielectric and morphological characteristics of the subpopulations of peripheral blood. In agreement with earlier findings, cell total capacitance varied with both cell size and plasma membrane folding and the dielectric properties of the NCI-60 cell types in suspension reflected the plasma membrane area and volume of the cells at their growth sites. Therefore, the behavior of cells in DEP-based manipulations is largely determined by their exterior morphological characteristics prior to release into suspension. As a consequence, DEP is able to discriminate between cells of similar size having different morphological origins, offering a significant advantage over size-based filtering for isolating circulating tumor cells, for example. The findings provide a framework for anticipating cell dielectric behavior on the basis of structure-function relationships and suggest that DEP should be widely applicable as a surface marker-independent method for sorting cells. PMID:23172680

Gascoyne, Peter R. C.; Shim, Sangjo; Noshari, Jamileh; Becker, Frederick F.; Stemke-Hale, Katherine

2013-01-01

259

A morphological and chemical study of Populus acuminata Rydberg  

Microsoft Academic Search

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

Daniel J. Crawford

1974-01-01

260

INTRODUCTION Researchers have long studied morphological adaptations that allow  

E-print Network

: they are prevalent in oceans worldwide with some species, such as the coralline Calliarthron cheilosporioides Manza plant tissues, adjacent genicular cells are only loosely connected to one another. Genicular cells fray

Denny, Mark

261

Zinc air refuelable battery: alternative zinc fuel morphologies and cell behavior  

SciTech Connect

Multicell zinc/air batteries have been tested previously in the laboratory and as part of the propulsion system of an electric bus; cut zinc wire was used as the anode material. This battery is refueled by a hydraulic transport of 0.5-1 mm zinc particles into hoppers above each cell. We report an investigation concerning alternative zinc fuel morphologies, and energy losses associated with refueling and with overnight or prolonged standby. Three types of fuel pellets were fabricated, tested and compared with results for cut wire: spheres produced in a fluidized bed electrolysis cell; elongated particles produced by gas-atomization; and pellets produced by chopping 1 mm porous plates made of compacted zinc fines. Relative sizes of the particles and cell gap dimensions are critical. All three types transported within the cell 1553 and showed acceptable discharge characteristics, but a fluidized bed approach appears especially attractive for owner/user recovery operations.

Cooper, J.F.; Krueger, R.

1997-01-01

262

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

NASA Astrophysics Data System (ADS)

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

Mahadevapuram, Rakesh C.

263

A morphological classification of retinal ganglion cells in the Japanese catshark Scyliorhinus torazame.  

PubMed

Retinal ganglion cells (GCs) in the Japanese catshark Scyliorhinus torazame were labeled retrogradely with biotinylated dextran amine (BDA3000). First the labeled cells were classified into 5 morphological types (types I-III: small GCs; types IV and V: large GCs) according to the size of the soma and the dendritic arborization pattern as seen in retinal wholemounts. Type I cells were stellate, with dendrites radiating in different directions. Type II cells had bipolar dendritic trees, with 2 primary dendrites extending in opposite directions. Type III cells had a single thick primary dendrite. Type IV cells were stellate, with dendrites covering a large area centered on the cell body. Type V cells were asymmetric, with most dendrites extending opposite to the axon as a large, fan-shaped dendritic field. Subsequently a wholemount was cross-sectioned, and we classified cells further into multiple subtypes according to the level of dendritic arborization within the inner plexiform layer. The present results suggest the existence of many types of GCs in elasmobranchs in addition to the 3 types of large GCs that have been characterized previously. Some of the newly described GC subtypes in the catshark retina appear to be similar to some of those reported in actinopterygians. PMID:24642951

Muguruma, Kaori; Stell, William K; Yamamoto, Naoyuki

2014-01-01

264

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

Microsoft Academic Search

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

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

2005-01-01

265

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

Microsoft Academic Search

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

L. D. Lehman-McKeeman

2000-01-01

266

Morphology evolution by controlling solvent-solute interactions using a binary solvent in bulk heterojunction solar cells  

NASA Astrophysics Data System (ADS)

Improved power conversion efficiency of poly(indacenodithiophene-co-phananthrene-quinoxaline) (PIDT-PhanQ)/[6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) based bulk- heterojunction (BHJ) solar cells was achieved upon adding tetrahydrofuran (THF) as a co-solvent to 1,2-dichlorobenzene (DCB). This reasonably large enhancement is achieved due to THF changes the morphology in the active layer by reducing the solvent-solute interaction. The Flory-Huggins interaction parameter and cohesive energy densities for PIDT-PhanQ and PD71BM with different solvents were further studied to understand the underlying phase separation mechanism in BHJ films.

Cho, Namchul; Yip, Hin-Lap; Jen, Alex K.-Y.

2013-06-01

267

Immortalization of human endothelial cells by murine sarcoma viruses, without morphologic transformation.  

PubMed

Amphotropic murine leukemia virus pseudotypes of murine sarcoma viruses containing the ras or mos oncogenes were constructed to permit efficient introduction of the sarcoma virus genome into early-passage human umbilical vein endothelial cells. The resulting cell lines were morphologically and phenotypically unchanged, retaining properties characteristic of differentiated endothelial cells. For example, the cells in a Kirsten sarcoma virus-modified line were found to biosynthesize and secrete von Willebrand factor in both a constitutive and regulated manner, and they contained ultrastructurally identifiable Weibel-Palade bodies, an endothelial cell-specific organelle. In contrast to the parent cultures, sarcoma virus-modified cells were able to proliferate indefinitely in culture. Examination of both Kirsten sarcoma and Moloney leukemia virus-modified lines indicated that the immortalized cells retained a diploid female karyotype after over 18 months in culture. In addition, the sarcoma virus-modified cells were able to grow independently of added endothelial cell growth factor. This growth factor autonomy does not appear to be due to autocrine production of a biologically cross-reactive growth factor. These immortal, virus-modified endothelial cells express large amounts of sarcoma virus-specific mRNA but no detectable helper virus or transforming virus activity. This technique for immortalization of primary human cells without alteration of the differentiated characteristics of the cell type is readily applied to a variety of human cell types. Moreover, the ability to separate the immortalizing and transforming activities of viral oncogenes should provide further understanding as to mechanisms of oncogene action. PMID:2826502

Faller, D V; Kourembanas, S; Ginsberg, D; Hannan, R; Collins, T; Ewenstein, B M; Pober, J S; Tantravahi, R

1988-01-01

268

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

PubMed Central

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

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

2013-01-01

269

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

270

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

PubMed Central

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

Gerstenberger, John P.; Occhipinti, Patricia

2012-01-01

271

Focal adhesion-localization of START-GAP1/DLC1 is essential for cell motility and morphology.  

PubMed

There is a class of GTPase activating proteins for the Rho family GTPases (RhoGAPs) that contain the steroidogenic acute regulatory protein (STAR)-related lipid transfer (START) domain. In mammals three genes encode such proteins and they are designated START-GAP1-3 or deleted in liver cancer 1-3 (DLC1-3). In this study, we examined the intracellular localization and roles of START-GAP1/DLC1 in cell motility. Immunofluorescence microscopic analysis of NRK cells and HeLa cells revealed that START-GAP1 was localized in focal adhesions. Amino acid residues 265-459 of START-GAP1 were found to be necessary for focal adhesion targeting and we name the region "the focal adhesion-targeting (FAT) domain." It was previously known that ectopic expression of START-GAP1 induced cell rounding. We demonstrated that the FAT domain of START-GAP1 was partially required for this morphological change. Furthermore, expression of this domain in HeLa cells resulted in dissociation of endogenous START-GAP1 from focal adhesions as a dominant negative modulator, reducing cell migration and spreading. Taken together, START-GAP1 is targeted to focal adhesions via the FAT domain and regulates actin rearrangement through down-regulation of active RhoA and Cdc42. Its absence from focal adhesions could, therefore, cause abnormal cell motility and spreading. PMID:19170769

Kawai, Katsuhisa; Iwamae, Yui; Yamaga, Masaki; Kiyota, Minoru; Ishii, Hiroko; Hirata, Hajime; Homma, Yoshimi; Yagisawa, Hitoshi

2009-02-01

272

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

NASA Astrophysics Data System (ADS)

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

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

2010-09-01

273

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

PubMed

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

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

2014-09-01

274

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

PubMed

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

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

2014-03-01

275

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

PubMed

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

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

2012-12-01

276

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

PubMed

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

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

2014-11-01

277

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

ERIC Educational Resources Information Center

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

Kristoffersen, Kristian Emil

2012-01-01

278

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

ERIC Educational Resources Information Center

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

Pittas, Evdokia; Nunes, Terezinha

2014-01-01

279

Cytokine Deposition Alters Leukocyte Morphology and Initial Recruitment of Monocytes and ??T Cells After Corneal Injury  

PubMed Central

Purpose. An in vivo mouse model reproducibly induces recurrent epithelial erosions in wild-type mice spontaneously 2 weeks after a single 1.5-mm corneal debridement wound made with a dulled blade. When 1.5-mm wounds are made by a rotating burr so that the corneal epithelial basement membrane is removed, corneas heal without developing erosions. Here, we characterize differences in cytokine deposition and changes in leukocytes between 0 and 6 hours after dulled-blade and rotating-burr wounding. Methods. BALB/c mice were used to study 1.5-mm corneal wounds made using a dulled blade or a rotating burr. Mice were studied immediately after wounding (0 hour) and at 6 hours in vivo and in vitro in organ culture. Corneas, corneal extracts, and collagenase digests from naïve and wounded mice were used for three-dimensional (3D) confocal imaging, cytokine arrays, and flow cytometry. Results. Confocal imaging showed CD45, a protein derived from leukocytes, accumulates at the wound edge by 3 and 6 hours after wounding in vivo but not in vitro with more CD45 accumulating after dulled-blade compared with rotating-burr wounds. Morphologic changes occurred in CD45+ leukocytes and higher levels for several cytokines were detected in the stromal wound bed within minutes following dulled-blade wounds. Flow cytometry showed significantly more monocytes (CD45+/CD11b+/Ly6C+) and ??T cells (CD45+/GL3+) recruited into the corneas of mice with dulled-blade wounds by 6 hours. Conclusions. Differences in cytokine-driven leukocyte responses are seen after dulled-blade debridement compared with rotating-burr injury. PMID:24677104

Pal-Ghosh, Sonali; Pajoohesh-Ganji, Ahdeah; Menko, A. Sue; Oh, Hye-young; Tadvalkar, Gauri; Saban, Daniel R.; Stepp, Mary Ann

2014-01-01

280

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

PubMed

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

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

2014-11-12

281

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

282

Study of the formed elements in MORPHOLOGY AND FUNCTION  

E-print Network

of Ribosomes and Lysosomes #12;9/10/2013 3 ENDOPLASMIC RETICULUM Lacelike network of flattened sheets, sac;9/10/2013 9 LYMPH NODE PLURIPOTENT STEM CELL CYTOKINES Glycoproteins that govern differentiation ­ Promote-ACTING (Multilineage) SCF (stem cell factor)- (CFU-GEMM, CFU-GM, CFU MK, BFU-E). Flt 3 Ligand ­ Inhibits apoptosis

283

A BIOCHEMICAL AND MORPHOLOGIC STUDY OF MYELINATION AND DEMYELINATION  

PubMed Central

Samples of normal grey matter, white matter, and peripheral nerves obtained from rats were incubated in Warburg vessels with glucose and a labelled lipide precursor (acetate, phosphate, choline, glycerol, glucose). The total lipides were then extracted and their radioactivity measured. The preparations were compared with respect to dry weight, lipide content, O2 uptake, and ability to incorporate the various substrates into the lipides. Grey matter was found to be the least damaged by incubation, white matter the most. Damage to the tissue depressed lipogenesis to a greater extent than respiration. Five substrates were compared with respect to their degree of incorporation into the lipides of the various preparations. White matter, which had a greater oxygen uptake than peripheral nerves, showed the lowest degree of incorporation for most of the substrates studied. The results suggest that there are considerable quantitative differences in the metabolism of central and peripheral myelin. In the sciatic preparations, oxygen uptake and lipogenesis from acetate were found to decrease from the proximal to the distal end of the nerve. This finding may be relevant to the pathogenesis of peripheral neuropathies. The growth and metabolic activity of peripheral nerves were studied in rats aged 1 to 500 days, and the biochemical and histological findings were correlated. The results indicated that the lipogenetic activity of the Schwann cell was lowest in the newborn animal, and reached its peak at about 20 days. Comparative data were also obtained from the cerebral cortex. The growth pattern of peripheral nerves was distinctly different from that of the brain. With respect to changes in tissue weight, respiration, and lipogenesis, growing peripheral nerve correlated with body weight, while the brain matured much more rapidly. PMID:13513913

Majno, Guido; Karnovsky, Manfred L.

1958-01-01

284

Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells.  

PubMed

Although the field of polymer solar cell has seen much progress in device performance in the past few years, several limitations are holding back its further development. For instance, current high-efficiency (>9.0%) cells are restricted to material combinations that are based on limited donor polymers and only one specific fullerene acceptor. Here we report the achievement of high-performance (efficiencies up to 10.8%, fill factors up to 77%) thick-film polymer solar cells for multiple polymer:fullerene combinations via the formation of a near-ideal polymer:fullerene morphology that contains highly crystalline yet reasonably small polymer domains. This morphology is controlled by the temperature-dependent aggregation behaviour of the donor polymers and is insensitive to the choice of fullerenes. The uncovered aggregation and design rules yield three high-efficiency (>10%) donor polymers and will allow further synthetic advances and matching of both the polymer and fullerene materials, potentially leading to significantly improved performance and increased design flexibility. PMID:25382026

Liu, Yuhang; Zhao, Jingbo; Li, Zhengke; Mu, Cheng; Ma, Wei; Hu, Huawei; Jiang, Kui; Lin, Haoran; Ade, Harald; Yan, He

2014-01-01

285

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

SciTech Connect

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

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

1984-10-01

286

Multiple mechanisms determine ER network morphology during the cell cycle in Xenopus egg extracts  

PubMed Central

In metazoans the endoplasmic reticulum (ER) changes during the cell cycle, with the nuclear envelope (NE) disassembling and reassembling during mitosis and the peripheral ER undergoing extensive remodeling. Here we address how ER morphology is generated during the cell cycle using crude and fractionated Xenopus laevis egg extracts. We show that in interphase the ER is concentrated at the microtubule (MT)-organizing center by dynein and is spread by outward extension of ER tubules through their association with plus ends of growing MTs. Fusion of membranes into an ER network is dependent on the guanosine triphosphatase atlastin (ATL). NE assembly requires fusion by both ATL and ER-soluble N-ethyl-maleimide–sensitive factor adaptor protein receptors. In mitotic extracts, the ER converts into a network of sheets connected by ER tubules and loses most of its interactions with MTs. Together, these results indicate that fusion of ER membranes by ATL and interaction of ER with growing MT ends and dynein cooperate to generate distinct ER morphologies during the cell cycle. PMID:24297752

Wang, Songyu; Romano, Fabian B.; Field, Christine M.

2013-01-01

287

Morphological and ultrastructural changes in vegetative cells and heterocysts of Anabaena variabilis grown with fructose.  

PubMed Central

The morphology and ultrastructure of Anabaena variabilis grown in medium with and without 40 mM fructose were compared. Vegetative cells and young heterocysts in fructose-supplemented medium were significantly larger, were filled with glycogen granules, and had fewer thylakoids. Developing heterocysts contained large numbers of glycogen granules well into mature stages, and envelope formation was precocious. As heterocysts enlarged in fructose medium, their shape became more broadly oblong compared with the more rectangular heterocysts in fructose-free medium. Images PMID:3100507

Lang, N J; Krupp, J M; Koller, A L

1987-01-01

288

In vitro cytotoxicity and morphological assessment of smoke from polymer combustion in human lung derived cells (A549).  

PubMed

The application of polymer and composites in building and modern transport interiors raises concerns of potential health hazards during combustion. Cytotoxicity and morphological assessment of smoke from polymer combustion in human lung derived cells (A549) has been investigated. A laboratory scale vertical tube furnace was used for the generation of combustion products. A range of materials used in the building and transport industry including high density-polyethylene (HDPE), polypropylene (PP), polycarbonate (PC), and polyvinyl chloride (PVC), fiberglass reinforced polymers (FRPs), and melamine faced plywood (MFP) were studied. The exposure of combustion toxicants to human lung cells (A549) at the air/liquid interface was acquired using a Harvard Navicyte Chamber. Cytotoxic effects on human cells were assessed based on cell viability using a selected in vitro cytotoxicity assays, including NRU (neutral red uptake) and ATP (adenosine triphosphate). Morphological assessment on the effects of combustion products in human lung cells from selected materials including PVC, FRP and MFP was assessed using scanning electron microscopy (SEM). The volatile organic compounds from thermal decomposition products were identified using ATD-GCMS (Automatic Thermal Desorption Gas Chromatography Mass Spectrometry). NOAEC (No Observable Adverse Effect Concentration), IC(10) (10% inhibitory concentration), IC(50) (50% inhibitory concentration), and TLC (Total Lethal Concentration) values (mg/l) were generated. The following toxicity ranking was observed from the most toxic material to the least toxic using the NRU assay: PVC>PP>HDPE>PC >FRP-10>MFP>FRP-16; and the ATP assay: PVC>HDPE>PP>FRP-10>FRP-16>MFP>PC. The method described here could potentially be an alternative to current fire toxicity standards. PMID:22227179

Lestari, F; Hayes, A J; Green, A R; Chattopadhyay, G

2012-04-01

289

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

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

290

Light scatter characteristics of blast cells in acute myeloid leukaemia: association with morphology and immunophenotype.  

PubMed Central

AIMS--To analyse the forward scatter/side scatter (FSC/SSC) distribution of acute myeloblastic leukaemia (AML) blast cells in order to assess whether it correlates with their morphology, immunophenotype, and clinical and biological disease characteristics. METHODS--FSC/SSC patterns were established upon taking into account the localisation of the residual T lymphocytes in the FSC/SSC dot plot as an internal biological standard. One hundred and seventy one newly diagnosed AML patients were analysed and five different FSC/SSC patterns were established. These five patterns could be grouped into two major categories taking into account the FSC/SSC distribution of normal cells in a bone marrow aspirate: immature patterns (1 and 2) and mature patterns (3, 4, and 5). These FSC/SSC patterns were correlated with different clinical and biological characteristics of AML patients. RESULTS--No significant associations were detected in relation to the clinical and haematological disease characteristics and the prognosis of these patients. By contrast there was a significant correlation between the FSC/SSC pattern of the AML blast cells and the FAB classification. An increased reactivity for the antigens associated with myeloid differentiation such as CD13, CD33, CD11b, CD15, CD14, CD4, CD56, and/or CD16 was detected among cases showing a mature FSC/SSC pattern (3, 4, and 5), both in the whole series and even within each of the FAB AML subtypes. By contrast, the reactivity for the CD34 precursor cell associated antigen was higher among those cases displaying an immature FSC/SSC pattern, this being observed even within each FAB subgroup. CONCLUSIONS--The FSC/SSC pattern distribution of AML blast cells not only provides an additional objective and reproductible system for the classification of these leukaemias but it may also represent a connection between the FAB morphological groups and the immunophenotypic classification of AML patients. Images PMID:7629293

Vidriales, M B; Orfao, A; López-Berges, M C; González, M; López-Macedo, A; García, M A; Galende, J; San Miguel, J F

1995-01-01

291

Ovarian Cancer Cell Line Panel (OCCP): Clinical Importance of In Vitro Morphological Subtypes  

PubMed Central

Epithelial ovarian cancer is a highly heterogeneous disease and remains the most lethal gynaecological malignancy in the Western world. Therapeutic approaches need to account for inter-patient and intra-tumoural heterogeneity and detailed characterization of in vitro models representing the different histological and molecular ovarian cancer subtypes is critical to enable reliable preclinical testing. There are approximately 100 publicly available ovarian cancer cell lines but their cellular and molecular characteristics are largely undescribed. We have characterized 39 ovarian cancer cell lines under uniform conditions for growth characteristics, mRNA/microRNA expression, exon sequencing, drug response for clinically-relevant therapeutics and collated all available information on the original clinical features and site of origin. We tested for statistical associations between the cellular and molecular features of the lines and clinical features. Of the 39 ovarian cancer cell lines, 14 were assigned as high-grade serous, four serous-type, one low-grade serous and 20 non-serous type. Three morphological subtypes: Epithelial (n?=?21), Round (n?=?7) and Spindle (n?=?12) were identified that showed distinct biological and molecular characteristics, including overexpression of cell movement and migration-associated genes in the Spindle subtype. Comparison with the original clinical data showed association of the spindle-like tumours with metastasis, advanced stage, suboptimal debulking and poor prognosis. In addition, the expression profiles of Spindle, Round and Epithelial morphologies clustered with the previously described C1-stromal, C5-mesenchymal and C4 ovarian subtype expression profiles respectively. Comprehensive profiling of 39 ovarian cancer cell lines under controlled, uniform conditions demonstrates clinically relevant cellular and genomic characteristics. This data provides a rational basis for selecting models to develop specific treatment approaches for histological and molecular subtypes of ovarian cancer. PMID:25230021

Beaufort, Corine M.; Helmijr, Jean C. A.; Piskorz, Anna M.; Hoogstraat, Marlous; Ruigrok-Ritstier, Kirsten; Besselink, Nicolle; Murtaza, Muhammed; van IJcken, Wilfred F. J.; Heine, Anouk A. J.; Smid, Marcel; Koudijs, Marco J.; Brenton, James D.; Berns, Els M. J. J.; Helleman, Jozien

2014-01-01

292

Study of Structural Morphology of Hemp Fiber from the Micro to the Nanoscale  

Microsoft Academic Search

The focus of this work has been to study how high pressure defibrillation and chemical purification affect the hemp fiber\\u000a morphology from micro to nanoscale. Microscopy techniques, chemical analysis and X-ray diffraction were used to study the\\u000a structure and properties of the prepared micro and nanofibers. Microscopy studies showed that the used individualization processes\\u000a lead to a unique morphology of

Bei Wang; Mohini Sain; Kristiina Oksman

2007-01-01

293

Molecular Weight Dependence of the Morphology in P3HT:PCBM Solar Cells.  

PubMed

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

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

2014-11-26

294

Effects of 5-fluorouracil in nuclear and cellular morphology, proliferation, cell cycle, apoptosis, cytoskeletal and caveolar distribution in primary cultures of smooth muscle cells.  

PubMed

Colon cancer is one of the most prevalent types of cancer in the world and is one of the leading causes of cancer death. The anti-metabolite 5- fluorouracil (5-FU) is widely used in the treatment of patients with colon cancer and other cancer types. 5-FU-based chemotherapy has been shown to be very efficient in the improvement of overall survival of the patients and for the eradication of the disease. Unfortunately, common side effects of 5-FU include severe alterations in the motility of the gastrointestinal tissues. Nevertheless, the molecular and cellular effects of 5-FU in smooth muscle cells are poorly understood. Primary smooth muscle cell cultures are an important tool for studies of the biological consequences of 5-FU at the cellular level. The avian gizzard is one of the most robust organs of smooth muscle cells. Here we studied the molecular and cellular effects of the chemotherapic drug 5-FU in a primary culture of chick gizzard smooth muscle cells. We found that treatment of smooth muscle cells with 5-FU inhibits cell proliferation by the arrest of cells in the G1 phase of cell cycle and induce apoptosis. 5-FU induced a decrease in the percentage of histone H3-positive cells. Treatment of cells with 5-FU induced changes in cellular and nuclear morphology, a decrease in the number of stress fibers and a major decrease in the number of caveolin-3 positive cells. Our results suggest that the disorganization of the actin cytoskeleton and the reduction of caveolin-3 expression could explain the alterations in contractility observed in patients treated with 5-FU. These findings might have an impact in the understanding of the cellular effects of 5-FU in smooth muscle tissues and might help the improvement of new therapeutic protocols for the treatment of colon cancer. PMID:23646193

Filgueiras, Marcelo de Carvalho; Morrot, Alexandre; Soares, Pedro Marcos Gomes; Costa, Manoel Luis; Mermelstein, Cláudia

2013-01-01

295

Effects of 5-Fluorouracil in Nuclear and Cellular Morphology, Proliferation, Cell Cycle, Apoptosis, Cytoskeletal and Caveolar Distribution in Primary Cultures of Smooth Muscle Cells  

PubMed Central

Colon cancer is one of the most prevalent types of cancer in the world and is one of the leading causes of cancer death. The anti-metabolite 5- fluorouracil (5-FU) is widely used in the treatment of patients with colon cancer and other cancer types. 5-FU-based chemotherapy has been shown to be very efficient in the improvement of overall survival of the patients and for the eradication of the disease. Unfortunately, common side effects of 5-FU include severe alterations in the motility of the gastrointestinal tissues. Nevertheless, the molecular and cellular effects of 5-FU in smooth muscle cells are poorly understood. Primary smooth muscle cell cultures are an important tool for studies of the biological consequences of 5-FU at the cellular level. The avian gizzard is one of the most robust organs of smooth muscle cells. Here we studied the molecular and cellular effects of the chemotherapic drug 5-FU in a primary culture of chick gizzard smooth muscle cells. We found that treatment of smooth muscle cells with 5-FU inhibits cell proliferation by the arrest of cells in the G1 phase of cell cycle and induce apoptosis. 5-FU induced a decrease in the percentage of histone H3-positive cells. Treatment of cells with 5-FU induced changes in cellular and nuclear morphology, a decrease in the number of stress fibers and a major decrease in the number of caveolin-3 positive cells. Our results suggest that the disorganization of the actin cytoskeleton and the reduction of caveolin-3 expression could explain the alterations in contractility observed in patients treated with 5-FU. These findings might have an impact in the understanding of the cellular effects of 5-FU in smooth muscle tissues and might help the improvement of new therapeutic protocols for the treatment of colon cancer. PMID:23646193

Filgueiras, Marcelo de Carvalho; Morrot, Alexandre; Soares, Pedro Marcos Gomes; Costa, Manoel Luis; Mermelstein, Claudia

2013-01-01

296

Adaptation-dependent changes of bipolar cell terminals in fish retina: Effects on overall morphology and spinule formation in Ma and Mb cells  

Microsoft Academic Search

We have investigated the effects of light and dark adaptation on the overall morphology of bipolar cell (BC) terminals in sublaminae a and b of the inner plexiform layer after labelling with Lucifer Yellow (LY) and PKC immunostaining using confocal laser scanning microscopy and serially sectioned material for electron microscopy. Three-dimensional reconstructed terminals showed marked adaptation-dependent changes of their morphology.

Uwe D. Behrens; Hans-Joachim Wagner

1996-01-01

297

Response of bone marrow derived connective tissue progenitor cell morphology and proliferation on geometrically modulated microtextured substrates  

PubMed Central

Varying geometry and layout of microposts on a cell culture substrate provides an effective technique for applying mechanical stimuli to living cells. In the current study, the optimal geometry and arrangement of microposts on the polydimethylsiloxane (PDMS) surfaces to enhance cell growth behavior were investigated. Human bone marrow derived connective tissue progenitor cells were cultured on PDMS substrates comprising unpatterned smooth surfaces and cylindrical post microtextures that were 10 µm in diameter, 4 heights (5, 10, 20 and 40 µm) and 3 pitches (10, 20, and 40 µm). With the same 10 µm diameter, post heights ranging from 5 to 40 µm resulted in a more than 535000 fold range of rigidity from 0.011 nNµm?1 (40 µm height) up to 5888 nNµm?1(5 µm height). Even though shorter microposts result in higher effective stiffness, decreasing post heights below the optimal value, 5 µm height micropost in this study decreased cell growth behavior. The maximum number of cells was observed on the post microtextures with 20 µm height and 10 µm inter-space, which exhibited a 675% increase relative to the smooth surfaces. The cells on all heights of post microtextures with 10 µm and 20 µm inter-spaces exhibited highly contoured morphology. Elucidating the cellular response to various external geometry cues enables us to better predict and control cellular behavior. In addition, knowledge of cell response to surface stimuli could lead to the incorporation of specific size post microtextures into surfaces of implants to achieve surface-textured scaffold materials for tissue engineering applications. PMID:23378044

Kim, Eun Jung; Fleischman, Aaron J.; Muschler, George F.; Roy, Shuvo

2013-01-01

298

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

299

A quantitative study of peculiarities in galaxy morphology  

NASA Astrophysics Data System (ADS)

I have developed a refined version of the asymmetry parameter first presented by Abraham et al. (1996). Coupled with a simple concentration index, this pair of indices, AW-CW, is compared to Abraham et al.'s log(AA)-log(C A) algorithm. These indices are then applied to a large sample of galaxies in the Hubble Deep Field with photometric redshifts from Connolly (1999). This allows investigation of trends at redshifts which have been largely inaccessible until now. The final sample consists of ~350 objects detected by the AW-CW algorithms with first-moment radii, r1 >= 0'.2 (corresponding to F814WAB ~ 26). The distribution of objects in the AW- CW plane is found to change with redshift. The region of the AW - CW plane populated by objects out to z ~ 1.2 is roughly constant. Accounting for bandpass shifting effects, this region resembles that populated by local bright galaxies (Frei et al. 1996) cosmologically simulated at z = 0.8. Beyond z ~ 1.2, the distribution of galaxies undergoes a significant change. Highly concentrated objects disappear from the AW-C W plane, while high asymmetry objects appear. The high concentration objects below z ~ 1.2 all have early-type morphologies. Very low resolution SEDs of these galaxies created using colors from Williams et al. (1996) are used to calculate the expected appearance of these objects at higher redshifts (z = 1.5 and 2.3). Assuming their luminosities and SEDs have not changed, one-third of the z ~ 0.8 objects would be undetected at z = 1.5, and 97% would disappear by z = 2.3. Any true drop in the number density of these objects would be completely masked by such strong selection effects. An increase in the number and degree of asymmetric objects is also seen beyond z ~ 1.2. Many of these objects exhibit multiple condensations, consistent with merging. Though the shifting of the ultraviolet galaxy spectrum into the F814W-band may be partially responsible, the majority of the increase in both number and degree of asymmetry appears to reflect a genuinely higher number density of asymmetric objects at earlier epochs. AW and CW are shown to be useful tools for exploring galaxy morphology over a wide range of redshifts. Future refinements combined with better SEDs and evolutionary models will undoubtedly reveal valuable insight into galaxy evolution.

Wu, Katherine Liang-Kai

300

Experiment K-7-28: Lung Morphology Study  

NASA Technical Reports Server (NTRS)

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

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

1994-01-01

301

Bacteroides gingivalis, Bacteroides asaccharolyticus , and Bacteroides melaninogenicus subspecies: Cell surface morphology and adherence to erythrocytes and human buccal epithelial cells  

Microsoft Academic Search

All study strains ofBacteroides gingivalis, B. asaccharolyticus, andB. melaninogenicus subspecies possessed numerous pilus-like fibers and capsule-like outer surface structures. The capsular morphology varied between the different species and subspecies.B. gingivalis strongly agglutinated 16 erythrocyte species studied.B. asaccharolyticus showed variable and weak agglutination of only a few erythrocyte species.B. melaninogenicus subsp.intermedius strains strongly agglutinated rabbit erythrocytes and exhibited variable, often weak

Katsuji Okuda; Jørgen Slots; Robert J. Genco

1981-01-01

302

Low-boiling-point solvent additives can also enable morphological control in polymer solar cells  

SciTech Connect

Processing organic photovoltaic (OPV) blend solutions with high-boiling-point solvent additives has recently been used for morphological control in bulk-heterojunction OPV cells. Here we show that even low-boiling-point solvents can be effective additives. When P3HT:PCBM OPV cells were processed with a low-boiling-point solvent tetrahydrafuran as an additive in parent solvent o-dichlorobenzene, charge extraction increased leading to fill factors as high as 69.5%, without low work-function cathodes, electrode buffer layers or thermal treatment. This was attributed to PCBM demixing from P3HT domains and better vertical phase separation, as indicated by photoluminescence lifetimes, hole mobilities, and shunt leakage currents. Dependence on solvent parameters and applicability beyond P3HT system was also investigated. (C) 2013 Elsevier B.V. All rights reserved.

Mahadevapuram, Rakesh C. [Ames Laboratory; Carr, John A. [Ames Laboratory; Chen, Yuqing [Ames Laboratory; Bose, Sayantan [Ames Laboratory; Nalwa, Kanwar S. [Ames Laboratory; Petrich, Jacob W. [Ames Laboratory; Chaudhary, Sumit [Ames Laboratory

2013-11-02

303

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

PubMed

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

Deng, Yu-Luen; Juang, Yi-Je

2014-03-15

304

Mouse type I IFN-producing cells are immature APCs with plasmacytoid morphology.  

PubMed

We show here that mouse interferon-alpha (IFN-alpha)-producing cells (mIPCs) are a unique subset of immature antigen-presenting cells (APCs) that secrete IFN-alpha upon stimulation with viruses. mIPCs have a plasmacytoid morphology, can be stained with an antibody to Ly6G and Ly6C (anti-Ly6G/C) and are Ly6C+B220+CD11cloCD4+; unlike other dendritic cell subsets, however, they do not express CD8alpha or CD11b. Although mIPCs undergo apoptosis in vitro, stimulation with viruses, IFN-alpha or CpG oligonucleotides enhanced their survival and T cell stimulatory activity. In vivo, mIPCs were the main producers of IFN-alpha in cytomegalovirus-infected mice, as depletion of Ly6G+/C+ cells abrogated IFN-alpha production. mIPCs produced interleukin 12 (IL-12) in response to viruses and CpG oligodeoxynucleotides, but not bacterial products. Although different pathogens can selectively engage various APC subsets for IL-12 production, IFN-alpha production is restricted to mIPCs' response to viral infection. PMID:11713464

Asselin-Paturel, C; Boonstra, A; Dalod, M; Durand, I; Yessaad, N; Dezutter-Dambuyant, C; Vicari, A; O'Garra, A; Biron, C; Brière, F; Trinchieri, G

2001-12-01

305

Morphological and functional characterization of leech circulating blood cells: role in immunity and neural repair.  

PubMed

Unlike most invertebrates, annelids possess a closed vascular system distinct from the coelomic liquid. The morphology and the function of leech blood cells are reported here. We have demonstrated the presence of a unique cell type which participates in various immune processes. In contrast to the mammalian spinal cord, the leech CNS is able to regenerate and restore function after injury. The close contact of the blood with the nerve cord also led us to explore the participation of blood in neural repair. Our data evidenced that, in addition to exerting peripheral immune functions, leech blood optimizes CNS neural repair through the release of neurotrophic substances. Circulating blood cells also appeared able to infiltrate the injured CNS where, in conjunction with microglia, they limit the formation of a scar. In mammals, CNS injury leads to the generation of a glial scar that blocks the mechanism of regeneration by preventing axonal regrowth. The results presented here constitute the first description of neuroimmune functions of invertebrate blood cells. Understanding the basic function of the peripheral circulating cells and their interactions with lesioned CNS in the leech would allow us to acquire insights into the complexity of the neuroimmune response of the injured mammalian brain. PMID:22159559

Boidin-Wichlacz, Céline; Vergote, David; Slomianny, Christian; Jouy, Nathalie; Salzet, Michel; Tasiemski, Aurélie

2012-05-01

306

Oestradiol and progesterone differentially alter cytoskeletal protein expression and flame cell morphology in Taenia crassiceps.  

PubMed

We examined the effects of oestradiol (E2) and progesterone (P4) on cytoskeletal protein expression in the helminth Taenia crassiceps - specifically actin, tubulin and myosin. These proteins assemble into flame cells, which constitute the parasite excretory system. Total protein extracts were obtained from E2- and P4-treated T. crassiceps cysticerci and untreated controls, and analysed by one- and two-dimensional protein electrophoresis, flow cytometry, immunofluorescence and videomicroscopy. Exposure of T. crassiceps cysticerci to E2 and P4 induced differential protein expression patterns compared with untreated controls. Changes in actin, tubulin and myosin expression were confirmed by flow cytometry of parasite cells and immunofluorescence. In addition, parasite morphology was altered in response to E2 and P4 versus controls. Flame cells were primarily affected at the level of the ciliary tuft, in association with the changes in actin, tubulin and myosin. We conclude that oestradiol and progesterone act directly on T. crassiceps cysticerci, altering actin, tubulin and myosin expression and thus affecting the assembly and function of flame cells. Our results increase our understanding of several aspects of the molecular crosstalk between host and parasite, which might be useful in designing anthelmintic drugs that exclusively impair parasitic proteins which mediate cell signaling and pathogenic reproduction and establishment. PMID:24879953

Ambrosio, Javier R; Ostoa-Saloma, Pedro; Palacios-Arreola, M Isabel; Ruíz-Rosado, Azucena; Sánchez-Orellana, Pedro L; Reynoso-Ducoing, Olivia; Nava-Castro, Karen E; Martínez-Velázquez, Nancy; Escobedo, Galileo; Ibarra-Coronado, Elizabeth G; Valverde-Islas, Laura; Morales-Montor, Jorge

2014-09-01

307

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

PubMed Central

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

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

2013-01-01

308

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

E-print Network

. In this study, we controlled the organization of human adipose derived stem cells using micro differentiation (B) of human adipose-derived stem cells (hASCs) in 1 : 1 mixture of osteogenic and adipogenic media for 4 days; Fig. S2: Alkaline phosphatase activity (ALP) of human adipose-derived stem cells (h

Linhardt, Robert J.

309

A study of the effects of radiation on the morphology, cytology and fertility of common dallisgrass  

E-print Network

A STUDY OF THE EFFECTS OF RADIATION ON THE MORPHOLOGY, CYTOLOGY AND FERTILITY OF COMMON DALLISGRASS A Thesis By Bert John Hoff Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE January f963 Major Subject Agronomy A STUDY OF THE EFFECTS OF RADIATION ON THE MORPHOLOGY, CYTOLOGY AND FERTILITY OF COMMON DALLISGRASS A Thesis By Bert John Hoff Approved as to style and content by...

Hoff, Bert John

2012-06-07

310

Bayesian Analysis of Morphological Changes Associated with Mild Cognitive Impairment: A Cross-Sectional Study  

Microsoft Academic Search

A new method, referred to as Bayesian Morphometry Algorithm (BMA), is presented, for morphology-function analysis of population-based medical imaging studies. In this paper, we apply BMA to a set of cross-sectional magnetic resonance images of subjects in the Baltimore Longitudinal Study of Aging, some of whom have very mild cognitive impairment, to demonstrate the algorithm's utility for determining morphological changes

Hanchuan Peng; Susan M. Resnick; Dinggang Shen; Christos Davatzikos; Edward H. Herskovits

311

Functional and morphological alterations of mitochondria in pancreatic beta cells from type 2 diabetic patients  

Microsoft Academic Search

Aims\\/hypothesis  Little information is available on the insulin release properties of pancreatic islets isolated from type 2 diabetic subjects. Since mitochondria represent the site where important metabolites that regulate insulin secretion are generated, we studied insulin release as well as mitochondrial function and morphology directly in pancreatic islets isolated from type 2 diabetic patients.Methods  Islets were prepared by collagenase digestion and density

M. Anello; R. Lupi; D. Spampinato; S. Piro; M. Masini; U. Boggi; S. Del Prato; A. M. Rabuazzo; F. Purrello; P. Marchetti

2005-01-01

312

Absence of CD9 Enhances Adhesion-Dependent Morphologic Differentiation, Survival, and Matrix Metalloproteinase-2 Production in Small Cell Lung Cancer Cells  

Microsoft Academic Search

While adhering to extracellular matrix proteins in vitro and in vivo, small cell lung cancer (SCLC) cells frequently show morphologic differentiation and are protected from apopto- sis. Integrin B1-mediated protein phosphorylation is sug- gested to be an essential signaling event in these processes. CD9 is an almost ubiquitously expressed tetraspanin protein that suppresses tumor progression by regulating cell motility and

Yoshiyuki Saito; Isao Tachibana; Yoshito Takeda; Hiroyuki Yamane; Ping He; Mayumi Suzuki; Seigo Minami; Takashi Kijima; Mitsuhiro Yoshida; Toru Kumagai; Tadashi Osaki; Ichiro Kawase

2006-01-01

313

MORPHOLOGICAL TRANSFORMATION AND CHROMOSOME DAMAGE BY AMSACRINE IN C3H/10T(1/2) CLONE 8 CELLS  

EPA Science Inventory

Morphological transformation, cell survival, chromosomal aberrations and micronuclei were measured in C3H/101/2CL8 cells after 24 hour exposure to amsacrine. A weak but dose-related increase in the percentage of dishes containing transformed foci occurred. As previously reported ...

314

Study on the Morphology Evolution and Purification of Electrorefined Silicon  

Microsoft Academic Search

A three-layer process and apparatus have been developed for electrorefining of silicon for solar cell application. The anode\\u000a is solidified from a hypereutectic solution of copper and MG silicon. At the temperature of operation (1223 K (950 °C)), elements\\u000a that have an electronegativity greater than that of silicon will remain at the anode (e.g., Cu, B, P, etc.) and then the Cu-Si

Yan-Qing Lai; Ming Jia; Zhong-Liang Tian; Jie Li; Jian-Feng Yan; Ji-Guang Yi; Zhi-Gang Wang; Ye-Xiang Liu

2010-01-01

315

Reversible morphological and functional abnormalities of RINm5F cells cultured on polystyrene sulfonate beads.  

PubMed

RINm5F cells (an insulin-secreting cell line) were cultured on PSSO3Na microbeads under static conditions. The cell growth rate was either identical to that of cells grown on plastic wells or slower, depending on the initial cell concentration. With both supports, it was similarly influenced by the fetal calf serum concentration in the culture medium, and protein content per cell was identical. However, no spreading was observed when cells were cultured on microbeads. RINm5F cells cultured on plastic wells responded to arginine + theophylline and to leucine + theophylline by a significant increase in insulin secretion. By contrast, in cells cultured on PSSO3Na microbeads, the increase in this secretion was only slight or nil. All these abnormalities were reversible. Thus, when cells cultured on microbeads were detached and seeded on plastic wells, normal spreading and insulin secretion were observed. Lastly, PSSO3Na beads had an acute suppressive effect on insulin secretion by cells cultured on plastic wells. This study provides an example of cell-biomaterial interaction in which cell growth is possible, but with altered cell function. PMID:3034913

Aubert, N; Reach, G; Serne, H; Jozefowicz, M

1987-05-01

316

MORPHOLOGIC VARIATION IN PNEUMOCOCCUS  

PubMed Central

The problem of morphologic variation in pneumococcus has been reviewed and the desirability of studying such variation through an examination of bacterial cells rather than of bacterial colonies has been pointed out. To further this objective, a new terminology to describe the morphologic variants of pneumococcus, potentially applicable to other bacterial species, has been proposed. A hitherto undefined morphologic variant of pneumococcus, the filamentous capsulated (fil+ S+) variant, has been defined and its relationship to the three previously recognized non-filamentous capsulated (fil- S+), nonfilamentous non-capsulated (fil- S-), and filamentous non-capsulated (fil+ S-) variants has been presented. PMID:13069647

Austrian, Robert

1953-01-01

317

Comparison study of biomimetic strontium-doped calcium phosphate coatings by electrochemical deposition and air plasma spray: morphology, composition and bioactive performance.  

PubMed

In this study, strontium-doped calcium phosphate coatings were deposited by electrochemical deposition and plasma spray under different process parameters to achieve various coating morphologies. The coating composition was investigated by energy dispersive X-ray spectroscopy and X-ray diffraction. The surface morphologies of the coatings were studied through scanning electron microscopy while the cytocompatibility and bioactivity of the strontium-doped calcium phosphate coatings were evaluated using bone cell culture using MC3T3-E1 osteoblast-like cells. The addition of strontium leads to enhanced proliferation suggesting the possible benefits of strontium incorporation in calcium phosphate coatings. The morphology and composition of deposited coatings showed a strong influence on the growth of cells. PMID:22528069

Li, Ling; Lu, Xia; Meng, Yizhi; Weyant, Christopher M

2012-10-01

318

Morphology evolution via self-organization and lateral and vertical diffusion in polymer:fullerene solar cell blends  

Microsoft Academic Search

Control of blend morphology at the microscopic scale is critical for optimizing the power conversion efficiency of plastic solar cells based on blends of conjugated polymer with fullerene derivatives. In the case of bulk heterojunctions of regioregular poly(3-hexylthiophene) (P3HT) and a soluble fullerene derivative ([6,6]-phenyl C61-butyric acid methyl ester, PCBM), both blend morphology and photovoltaic device performance are influenced by

Mariano Campoy-Quiles; Toby Ferenczi; Tiziano Agostinelli; Pablo G. Etchegoin; Youngkyoo Kim; Thomas D. Anthopoulos; Paul N. Stavrinou; Donal D. C. Bradley; Jenny Nelson

2008-01-01

319

Conduction velocity is related to morphological cell type in rat dorsal root ganglion neurones.  

PubMed Central

Combining intracellular recording and dye-injection techniques permitted direct correlation of neuronal soma size with peripheral nerve conduction velocity in individual neurones of the L4 dorsal root ganglion (d.r.g.) of the anaesthetized 5-8-week-old rat. The conduction velocities fell into two main groups; those greater than 14 m/s (A alpha and beta fibres) and those less than 8 m/s (A delta and C fibres). Fibres with conduction velocities in the A delta range (2.2-8 m/s) in the sciatic nerve between the sciatic notch and the neuronal soma in the d.r.g. often conducted more slowly, that is in the C-fibre range (less than 1.4 m/s), in the periphery from the tibial nerve to the sciatic notch. For the fast-conducting myelinated afferents, there was a loose positive correlation between cell size and the conduction velocity of the peripheral axon, whereas a clearer positive correlation existed between neuronal cell size and axonal conduction velocity both for A delta- and for C-fibre afferents. The relationship of the cell cross-sectional area (measured at the nucleolar level), to the cell volume for each neuronal soma was similar for the different conduction velocity groups. The somata of the fast-conducting myelinated A alpha and A beta fibres had a similar mean and range of cross-sectional areas to those of the large light cell population. The somata with A delta and C fibres were of a more uniform size and were restricted to the smaller cells within the ganglia. The mean and range of cross-sectional areas of the C cells was similar to those of the small dark cell population. A delta somata had a larger mean and range of cell sizes than those of the small dark cell population. The relationships of peripheral axon type to the morphological cell types are discussed. Images Plate 1 PMID:3999040

Harper, A A; Lawson, S N

1985-01-01

320

Morphological and morphometric study of the opossum's dorsal root ganglia neurons.  

PubMed

The ultrastructural characteristics and the morphometric evaluation of the different types of neurons present in the dorsal root ganglia (DRG) of the South American opossum (Didelphis albiventris) were studied. Four adult male animals were used and the neurons from cervical and lumbar DRG were removed and processed for histological and transmission electron microscopy observations. The morphometric data were obtained from serial sections stained by H/E and Masson's trichrome. The number of neurons in cervical and lumbar DRG was 22?300 and 31?000, respectively. About 68% of the cervical neurons and 62.5% of the lumbar neurons presented areas up to 1300?µm(2) and were considered as the small neurons of the DRG. The ultrastructural observations revealed two morphological types of neurons: clear large neurons and dark small neurons. The nuclei of both cell types are spherical and the chromatin is disperse and rarefected. The cytoplasm of the dark small neuron is more electron dense and shows a regular distribution of small mitochondria and many rough reticulum cisterns in the periphery. A small Golgi apparatus was close to the nucleus and many disperse neurofilaments occupy most parts of the cytoplasm. Smooth reticulum cisterns are rare and lipofucsin-like inclusions are present at some points. In the clear large neurons, the organelles are homogenously scattered through the cytoplasm. The neurofilaments are close packed forming bundles and small mitochondria and rough reticulum cisterns are disperse. Lipofucsin-like inclusions are more frequent in these cells. PMID:22500566

Soares, J C; Francia-Farje, L A D; Horta-Junior, J A C; Matheus, S M M

2012-01-01

321

Effect of axonal micro-tubules on the morphology of retinal nerve fibers studied by second-harmonic generation  

NASA Astrophysics Data System (ADS)

Many studies suggest that the degradation of microtubules in the retinal ganglion cells may be an early event in the progression of glaucoma. Because reflectance and birefringence of the retinal nerve fibers arise primarily from microtubules, the optical properties have been intensively studied for early detection of the disease. We previously reported a novel nonlinear optical signal from axonal microtubules for visualizing the retinal nerve fibers, namely second-harmonic generation (SHG). We demonstrate the use of axonal SHG to investigate the effect of microtubules on the morphology of the retinal nerve fiber bundles. Time-lapse SHG imaging of ex vivo rat retinal flat mounts was performed during pharmacological treatment of nocodazole, and the intensity of axonal SHG and the changes in nerve fiber bundle morphology were monitored. We found that the microtubule disruption does not lead to immediate modification in the morphology of the nerve fibers. Our results indicate that microtubular SHG may provide a useful means for sensitive detection of axonal injuries. Since the intrinsic radiation depends on the regular architecture of the cytoskeleton element as maintained by active cellular regulations, the intensity of signal reflects the health of the retinal ganglion cell axons.

Lim, Hyungsik; Danias, John

2012-11-01

322

Assimilation of nail keratin by Trichophyton mentagrophytes (Morphological study)  

Microsoft Academic Search

Summary In the course of onychomycosis due toTrichophyton mentagrophytes histological studies of nail plate were carried out in order to study growth of the fungus in the nail. The tissue changes caused by assimilation of the nail keratin by the fungus were also studied. Three phases of this process have been described: 1) growth of the fungus in the intercellular

J. Alkiewicz

1965-01-01

323

Effects of Low PBP2b Levels on Cell Morphology and Peptidoglycan Composition in Streptococcus pneumoniae R6  

PubMed Central

Streptococcus pneumoniae produces two class B penicillin-binding proteins, PBP2x and PBP2b, both of which are essential. It is generally assumed that PBP2x is specifically involved in septum formation, while PBP2b is dedicated to peripheral cell wall synthesis. However, little experimental evidence exists to substantiate this belief. In the present study, we obtained evidence that strongly supports the view that PBP2b is essential for peripheral peptidoglycan synthesis. Depletion of PBP2b expression gave rise to long chains of cells in which individual cells were compressed in the direction of the long axis and looked lentil shaped. This morphological change is consistent with a role for pneumococcal PBP2b in the synthesis of the lateral cell wall. Depletion of PBP2x, on the other hand, resulted in lemon-shaped and some elongated cells with a thickened midcell region. Low PBP2b levels gave rise to changes in the peptidoglycan layer that made pneumococci sensitive to exogenously added LytA during logarithmic growth and refractory to chain dispersion upon addition of LytB. Interestingly, analysis of the cell wall composition of PBP2b-depleted pneumococci revealed that they had a larger proportion of branched stem peptides in their peptidoglycan than the corresponding undepleted cells. Furthermore, MurM-deficient mutants, i.e., mutants lacking the ability to synthesize branched muropeptides, were found to require much higher levels of PBP2b to sustain growth than those required by MurM-proficient strains. These findings might help to explain why increased incorporation of branched muropeptides is required for high-level beta-lactam resistance in S. pneumoniae. PMID:23873916

Berg, Kari Helene; Stamsas, Gro Anita; Straume, Daniel

2013-01-01

324

The morphology of apoptosis and necrosis of fat cells after photodynamic treatment at a constant temperature in vitro  

NASA Astrophysics Data System (ADS)

Photodynamic therapy with temperature control is a new approach for treatment of obesity and cellulite. Cell death can occur under the action of various physical, chemical and biological factors. Depending on the inductor, this is apoptosis or necrosis. These two forms of cell death differ on the biochemical and morphological levels. Biochemical changes occur quickly enough and it raises difficulties of their detection. One of the morphological characteristics of apoptosis is a decrease (contraction) of cells, and necrosis - an increase in the size of the cell (swelling). This attribute simply determined visually using a digital microscope. The program was designed using LabVEIW media, which allowed us to develop the software for providing interaction with the measuring and control equipment, data collection, processing and displaying the information and results of calculations and simulations for the individual cells and ensembles of cells, and, in general, to automate process.

Yanina, Irina Yu.; Orlova, Tatyana G.; Tuchin, Valery V.; Altshuler, Gregory B.

2011-03-01

325

Functions of poly-gamma-glutamic acid (?-PGA) degradation genes in ?-PGA synthesis and cell morphology maintenance.  

PubMed

Poly-?-glutamic acid (?-PGA) is an important biopolymer with greatly potential in industrial and medical applications. In the present study, we constructed a metabolically engineered glutamate-independent Bacillus amyloliquefaciens LL3 strain with considerable ?-PGA production, which was carried out by single, double, and triple markerless deletions of three degradation genes pgdS, ggt, and cwlO. The highest ?-PGA production (7.12 g/L) was obtained from the pgdS and cwlO double-deletion strain NK-pc, which was 93 % higher than that of wild-type LL3 strain (3.69 g/L). The triple-gene-deletion strain NK-pgc showed a 28 % decrease in ?-PGA production, leading to a yield of 2.69 g/L. Furthermore, the cell morphologies of the mutant strains were also characterized. The cell length of cwlO deletion strains NK-c and NK-pc was shorter than that of the wild-type strain, while the ggt deletion strains NK-g, NK-pg, NK-gc, and NK-pgc showed longer cell lengths. This is the first report concerning the markerless deletion of ?-PGA degradation genes to improve ?-PGA production in a glutamate-independent strain and the first observation that ?-glutamyltranspeptidase (encoded by ggt) could be involved in the inhibition of cell elongation. PMID:24769902

Feng, Jun; Gao, Weixia; Gu, Yanyan; Zhang, Wei; Cao, Mingfeng; Song, Cunjiang; Zhang, Peng; Sun, Min; Yang, Chao; Wang, Shufang

2014-07-01

326

Pancreatic Islet Neuropeptide Y Overexpression Has Minimal Effect on Islet Morphology and ?-Cell Adaptation to High-Fat Diet.  

PubMed

Neuropeptide Y (NPY) is highly expressed in the hypothalamus, where it regulates feeding and energy homeostasis. Interestingly, NPY and its receptors are also expressed in peripheral tissues with roles in metabolism, including pancreatic islets. In islets, NPY is known to suppress insulin secretion acutely. In addition, the role of NPY in ?-cell de-differentiation has been postulated recently. Therefore, we studied transgenic mice expressing NPY under rat insulin promoter (TG) to determine the effects of chronic up-regulation of NPY on islet morphology and function. NPY levels were 25 times higher in islets of TG mice compared with wild-type (WT) littermates, whereas no differences in NPY expression were noted in the brains of TG and WT mice. Islet NPY secretion was 2.3-fold higher in TG compared with WT mice. There were no significant changes in body weight, glucose tolerance, or insulin sensitivity in TG mice fed regular rodent diet or high-fat diet (HF). Islet ?-cell area was comparable between TG and WT mice both on regular rodent and HF diets, indicating that NPY overexpression is insufficient to alter ?-cell maturation or the compensatory increase of ?-cell area on HF. One abnormality noted was that the glucose-stimulated insulin secretion in islets isolated from TG was reduced compared with those from WT mice on HF diet. Overall, an increase in islet NPY level has little impact on islet function and is insufficient to affect glucose homeostasis in mice. PMID:25285650

Machida, Yui; Bruinsma, Christine; Hallinger, Daniel R; Roper, Stephen M; Garcia, Eden; Trevino, Michelle B; Nadler, Joseph; Ahima, Rexford; Imai, Yumi

2014-12-01

327

Beach morphology monitoring in the Columbia River Littoral Cell: 1997-2005  

USGS Publications Warehouse

This report describes methods used, data collected, and results of the Beach Morphology Monitoring Program in the Columbia River Littoral Cell (CRLC) from 1997 to 2005. A collaborative group primarily consisting of the US Geological Survey and the Washington State Department of Ecology performed this work. Beach Monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). Sediment size distribution data was also collected as part of this effort. The monitoring program was designed to: 1) quantify the short- to medium-term (seasonal to interannual) beach change rates and morphological variability along the CRLC and assess the processes responsible for these changes; 2) collect beach state data (i.e., grain size, beach slope, and dune/sandbar height/position) to enhance the conceptual understanding of CRLC functioning and refine predictions of future coastal change and hazards; 3) compare and contrast the scales of environmental forcing and beach morphodynamics in the CRLC to other coastlines of the world; and 4) provide beach change data in a useful format to land use managers.

Ruggiero, Peter; Eshleman, Jodi L.; Kingsley, Etienne; Thompson, David M.; Voigt, Brian; Kaminsky, George M.; Gelfenbaum, Guy

2007-01-01

328

Trolox-Sensitive Reactive Oxygen Species Regulate Mitochondrial Morphology, Oxidative Phosphorylation and Cytosolic Calcium Handling in Healthy Cells  

PubMed Central

Abstract Aims: Cell regulation by signaling reactive oxygen species (sROS) is often incorrectly studied through extracellular oxidant addition. Here, we used the membrane-permeable antioxidant Trolox to examine the role of sROS in mitochondrial morphology, oxidative phosphorylation (OXPHOS), and cytosolic calcium (Ca2+) handling in healthy human skin fibroblasts. Results and Innovation: Trolox treatment reduced the levels of 5-(and-6)-chloromethyl-2?,7?-dichlorodihydro-fluorescein (CM-H2DCF) oxidizing ROS, lowered cellular lipid peroxidation, and induced a less oxidized mitochondrial thiol redox state. This was paralleled by increased glutathione- and mitofusin-dependent mitochondrial filamentation, increased expression of fully assembled mitochondrial complex I, elevated activity of citrate synthase and OXPHOS enzymes, and a higher cellular O2 consumption. In contrast, Trolox did not alter hydroethidium oxidation, cytosolic thiol redox state, mitochondrial NAD(P)H levels, or mitochondrial membrane potential. Whole genome expression profiling revealed that Trolox did not trigger significant changes in gene expression, suggesting that Trolox acts downstream of this process. Cytosolic Ca2+ transients, induced by the hormone bradykinin, were of a higher amplitude and decayed faster in Trolox-treated cells. These effects were dose-dependently antagonized by hydrogen peroxide. Conclusions: Our findings suggest that Trolox-sensitive sROS are upstream regulators of mitochondrial mitofusin levels, morphology, and function in healthy human skin fibroblasts. This information not only facilitates the interpretation of antioxidant effects in cell models (of oxidative-stress), but also contributes to a better understanding of ROS-related human pathologies, including mitochondrial disorders. Antioxid. Redox Signal. 17, 1657–1669. PMID:22559215

Distelmaier, Felix; Valsecchi, Federica; Forkink, Marleen; van Emst-de Vries, Sjenet; Swarts, Herman G.; Rodenburg, Richard J.T.; Verwiel, Eugene T.P.; Smeitink, Jan A.M.; Willems, Peter H.G.M.

2012-01-01

329

Morphology study of progesterone polymorphs prepared by polymer-induced heteronucleation (PIHn).  

PubMed

In this article, morphology of progesterone polymorphs prepared by polymer-induced heteronucleation (PIHn) technique was studied. Hydroxypropyl methylcellulose(HPMC), such as dextran T-500 and gelatin G-9382, polyisoprene (PI), and acrylonitrile/butadiene copolymer (NBR) were used as substrates. The crystallizations were performed by solvent evaporation at room temperature from 0.5, 10, and 40 mg/ml solutions in chloroform and acetone. Progesterone polymorphs were identified by X-ray diffraction. Differential scanning calorimetry and total attenuated reflectance infrared spectroscopy were used as complementary techniques in the identification. Depending on the polymeric matrix and the concentration used, form 1, form 2, or mixture of both polymorphs were obtained. Scanning electron microscopy pictures evidenced difference in morphology and in homogeneity of the two progesterone polymorphs. These polymorphs prepared by PIHn, did not present a distinctive morphology that allows identifying polymorph by its crystal habit. Hence, polymeric matrix induced the crystallization, affecting polymorphism and morphology. PMID:23034679

Araya-Sibaja, Andrea M A; Fandaruff, Cinira; Campos, Carlos E M; Soldi, Valdir; Cardoso, Simone G; Cuffini, Silvia L

2013-01-01

330

Laser synthesized super-hydrophobic conducting carbon with broccoli-type morphology as a counter-electrode for dye sensitized solar cells  

NASA Astrophysics Data System (ADS)

A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode.A laser photochemical process is introduced to realize superhydrophobic conducting carbon coatings with broccoli-type hierarchical morphology for use as a metal-free counter electrode in a dye sensitized solar cell. The process involves pulsed excimer laser irradiation of a thin layer of liquid haloaromatic organic solvent o-dichlorobenzene (DCB). The coating reflects a carbon nanoparticle-self assembled and process-controlled morphology that yields solar to electric power conversion efficiency of 5.1% as opposed to 6.2% obtained with the conventional Pt-based electrode. Electronic supplementary information (ESI) available: Materials and equipment details, solar cell fabrication protocol, electrolyte spreading time measurement details, XPS spectra, electronic study, film adhesion test detailed analysis and field emission results. See DOI: 10.1039/c2nr32082g

Gokhale, Rohan; Agarkar, Shruti; Debgupta, Joyashish; Shinde, Deodatta; Lefez, Benoit; Banerjee, Abhik; Jog, Jyoti; More, Mahendra; Hannoyer, Beatrice; Ogale, Satishchandra

2012-10-01

331

Morphology and dynamics of piercement structures: an integrated laboratory and numerical study  

NASA Astrophysics Data System (ADS)

Piercement structures are numerous in many geological settings, including pockmarks, mud volcanoes, hydrothermal vents, maar-diatreme volcanoes, volcanic conduits in stratovolcanoes, and kimberlite volcanoes. These piercement structures exhibit various shapes, from sub-vertical pipes piercing through the country rock to open and wide conduits, such as volcanic craters resulting from volcanic explosions (e.g., Mount Pinatubo). In this contribution, we present an integrated laboratory/numerical study to constrain the dynamics of piercement structures and unravel the processes that control their morphology. The laboratory experiments consist of a Hele-Shaw cell filled with a pack of cohesive fine-grained granular material, at the bottom of which a volume V t of pressurized air is injected at high velocity. As a result of air injection, a piercement structure develops through the medium, and its morphology and evolution is monitored with an ultra-fast camera. We varied systematically the thickness of the model h and the injection pressure P , and show that two morphologies of piercement structures develop: vertical and V-shaped conduits. In a phase diagram with h and P as horizontal and vertical axes, respectively, the two morphologies group into two distinct domains separated by a transition line of critical slope P-h. This phase diagram shows that vertical conduits form for high P /low h, whereas V-shaped conduits form for low P /high h. 2D numerical simulations are performed using Sage, a finite volume hydrocode developed at the Los Alamos National Laboratory. We ran simulations and varied systematically the input pressure P and the strength of the country rock T . Our simulations produced three types of piercement structures: vertical, sub-horizontal and V-shaped conduits. In a phase diagram with T and P as horizontal and vertical axes, respectively, the three morphologies group into distinct domains separated by transition lines of critical slopes P-T . Vertical conduits form for high P /low T , whereas V-shaped conduits form for low P /high T . Sub-horizontal conduits form at intermediate values of P and T . Stress maps computed from the simulations show that the V-shaped/sub-horizontal and vertical conduits do not correspond to the same dynamics. Vertical conduits form when the country rock behaves in a plastic manner, i.e. like unconsolidated rock. In contrast, V-shaped and horizontal conduits form when the country rock behaves mostly in an elastic manner, and the conduit corresponds to a fracture-like feature. The close similarities between our laboratory and numerical results allow us to define a new dimensionless parameter, the energy density Ie = V tP-h3T , which corresponds to the ratio between the input energy and the potential energy for fracturing of the country rock. Our results show that Ie is a primary controlling factor for the dynamics of piercement structures: when Ie is small, the country rock remains competent, and the piercement proceeds like fracturing, leading to V-shaped or horizontal conduits. In contrast, when Ie is large, the country rock looses its competence and behaves like unconsolidated rock, and the piercement structure develops vertically.

Galland, Olivier; Gisler, Galen R.; Haug, Øystein T.

2013-04-01

332

RhoGTPases and p53 Are Involved in the Morphological Appearance and Interferon-? Response of Hairy Cells  

PubMed Central

Hairy cell leukemia is an uncommon B-cell lymphoproliferative disease of unknown etiology in which tumor cells display characteristic microfilamentous membrane projections. Another striking feature of the disease is its exquisite sensitivity to interferon (IFN)-?. So far, none of the known IFN-? regulatory properties have explained IFN-? responsiveness nor have they taken into account the morphological characteristics of hairy cells. IFN-? profoundly alters cytoskeletal organization of hairy cells and causes reversion of the hairy appearance into a rounded morphology. Because cytoskeletal rearrangements are controlled by the Rho family of GTPases, we investigated the GTPase activation status in hairy cells and their regulation by IFN-?. Using immunolocalization techniques and biochemical assays, we demonstrate that hairy cells display high levels of active Cdc42 and Rac1 and that IFN-? down-regulates these activities. In sharp contrast, RhoA activity was low in hairy cells but was increased by IFN-? treatment. Finally, IFN-?-mediated morphological changes also implicated a p53-induced response. These observations shed light on the mechanism of action of IFN-? in hairy cell leukemia and are of potential relevance for the therapeutical applications of this cytokine. PMID:16436670

Chaigne-Delalande, Benjamin; Deuve, Lynda; Reuzeau, Edith; Basoni, Caroline; Lafarge, David; Varon, Christine; Tatin, Florence; Anies, Guerric; Garand, Richard; Kramer, Ijsbrand; Genot, Elisabeth

2006-01-01

333

Mechanism of benign biliary stricture: A morphological and immunohistochemical study  

PubMed Central

AIM: To explore the mechanism of benign biliary stricture. METHODS: A model of trauma of bile duct was established in 28 dogs. The anastomosed tissues were resected and examined by light and electron microscopes on day 3, in wk 1, 3 and mo 3, 6 after operation. CD68, TGF-?1 and ?-SMA were examined by immunohistochemical staining, respectively. RESULTS: The mucosal epithelium of the bile duct was slowly recovered, chronic inflammation lasted for a long time, fibroblasts proliferated actively, extracellular matrix was over-deposited. Myofibroblasts functioned actively and lasted through the whole process. The expression of macrophages in lamina propria under mucosa, TGF-?1 in granulation tissue, fibroblasts and endothelial cells of blood vessels, ?-SMA in myofiroblasts were rather strong from the 1st wk to the 6th mo after operation. CONCLUSION: The type of healing occurring in bile duct belongs to overhealing. Myofibroblasts are the main cause for scar contracture and stricture of bile duct. High expressions of CD68, TGF-?1 and ?-SMA are closely related to the active proliferation of fibroblasts, extracellular matrix over-deposition and scar contracture of bile duct. PMID:15633235

Geng, Zhi-Min; Yao, Ying-Min; Liu, Qing-Guang; Niu, Xin-Jie; Liu, Xiao-Gong

2005-01-01

334

Study on the Morphology Evolution and Purification of Electrorefined Silicon  

NASA Astrophysics Data System (ADS)

A three-layer process and apparatus have been developed for electrorefining of silicon for solar cell application. The anode is solidified from a hypereutectic solution of copper and MG silicon. At the temperature of operation (1223 K (950 °C)), elements that have an electronegativity greater than that of silicon will remain at the anode ( e.g., Cu, B, P, etc.) and then the Cu-Si phase can be used under certain conditions as a filter for purifying silicon with an electrorefining process. According to the stable liquid electrode reactive surface, high current density is possible during electrorefining and such advantages obviously improve the rate of deposition, which is a key point to reach commercial development. Deposited silicon particles are found embedded in electrolyte. Furthermore, with increasing operation time and current density, recombination of silicon particles is revealed and yields silicon balls with a diameter of 2 cm. The analysis of the anode feed and refined silicon shows a remarkable reduction of B and P concentrations, from 12.7 to 2.4 ppmw and 98.6 to 4.3 ppmw, respectively. Besides, particular mention should be made of efficient removal of impurities such as Fe, Mn, and Ti, which are present in significant quantities in the anode feed.

Lai, Yan-Qing; Jia, Ming; Tian, Zhong-Liang; Li, Jie; Yan, Jian-Feng; Yi, Ji-Guang; Wang, Zhi-Gang; Liu, Ye-Xiang

2010-04-01

335

Control of superlattice morphology in GaAs sub1-subxPsubx cascade cells  

NASA Technical Reports Server (NTRS)

Superlattices of GaAs(1-x)p(x) are being incorporated into cascade solar cell structures in order to reduce the dislocation density in the top cells and thus reduce recombination loss and increase output voltage. For a superlattice to effectively block the propagation of dislocations its average composition must be equal to that of the layer beneath it (from efficiency considerations for a cascade cell, the average composition should be about GaAs(.7)P(.3). When superlattices of this approximate composition were grown on GaAs by MOCVD, severe distortion of the crystal layers was observed. The essential features of this distortion are nonplanar morphology and accelerated etching in regions containing excess phosphorus and clusters of dislocations. Similar observations have been made with superlattices grown with two other MOCVD systems, indicating that the problem is of fundamental technological significance, not just an artifact of one particular growth system. The nature of the distortion effect is described, and several strategies for preventing its occurrence are presented.

Blakeslee, A. E.; Kibbler, A.

1985-01-01

336

Improved method for the quantification of motility in glia and other morphologically complex cells.  

PubMed

Cells such as astrocytes and radial glia with many densely ramified, fine processes pose particular challenges for the quantification of structural motility. Here we report the development of a method to calculate a motility index for individual cells with complex, dynamic morphologies. This motility index relies on boxcar averaging of the difference images generated by subtraction of images collected at consecutive time points. An image preprocessing step involving 2D projection, edge detection, and dilation of the raw images is first applied in order to binarize the images. The boxcar averaging of difference images diminishes the impact of artifactual pixel fluctuations while accentuating the group-wise changes in pixel values which are more likely to represent real biological movement. Importantly, this provides a value that correlates with mean process elongation and retraction rates without requiring detailed reconstructions of very complex cells. We also demonstrate that additional increases in the sensitivity of the method can be obtained by denoising images using the temporal frequency power spectra, based on the fact that rapid intensity fluctuations over time are mainly due to imaging artifact. The MATLAB programs implementing these motility analysis methods, complete with user-friendly graphical interfaces, have been made publicly available for download. PMID:24349799

Sild, Mari; Chatelain, Robert P; Ruthazer, Edward S

2013-01-01

337

Improved Method for the Quantification of Motility in Glia and Other Morphologically Complex Cells  

PubMed Central

Cells such as astrocytes and radial glia with many densely ramified, fine processes pose particular challenges for the quantification of structural motility. Here we report the development of a method to calculate a motility index for individual cells with complex, dynamic morphologies. This motility index relies on boxcar averaging of the difference images generated by subtraction of images collected at consecutive time points. An image preprocessing step involving 2D projection, edge detection, and dilation of the raw images is first applied in order to binarize the images. The boxcar averaging of difference images diminishes the impact of artifactual pixel fluctuations while accentuating the group-wise changes in pixel values which are more likely to represent real biological movement. Importantly, this provides a value that correlates with mean process elongation and retraction rates without requiring detailed reconstructions of very complex cells. We also demonstrate that additional increases in the sensitivity of the method can be obtained by denoising images using the temporal frequency power spectra, based on the fact that rapid intensity fluctuations over time are mainly due to imaging artifact. The MATLAB programs implementing these motility analysis methods, complete with user-friendly graphical interfaces, have been made publicly available for download. PMID:24349799

Sild, Mari; Chatelain, Robert P.; Ruthazer, Edward S.

2013-01-01

338

Distribution of morphological cells in the southern littoral of Sicily (Italy)  

NASA Astrophysics Data System (ADS)

A geomorphologic approach, combined with GIS spatial analysis, was used to investigate a 90 Km long coastal sector in Southern Sicily, Italy. Applied methodology allowed the determination of coastal erosion/accretion areas, general sediment circulation patterns and littoral cell distribution. The investigated littoral is recording important coastal erosion problems, mainly linked to the construction of ports and harbours. Such structures, as well as natural headlands, divide the littoral in morphological cells. Most important artificial limits are observed in correspondence with the ports and harbours of Scoglitti, Punta Secca, Donnalucata and Pozzallo and a haulage zone at Marina di Ragusa. Scoglitti, Punta Secca, Marina di Ragusa and Donnalucata structures work as „transit" limits which generate accretion on the west side parts and erosion on the east side parts. Pozzallo port works as a „convergent" limit because it records accretion at both sides. Most important natural structures are observed at Punta Zafaglione, P. Braccetto and Cava d'Aliga and they work as convergent, divergent and transit limits. Free limits also exist but their location changes according to wave approaching characteristics. The knowledge of littoral cell distribution acquires a great importance in the investigated littoral for the management of coastal erosion processes, which may be mitigated by the installation of by-passing systems in ports and harbours.

Anfuso, G.; Martínez Del Pozo, J. A.; Monaca, A.

2009-04-01

339

Nanoscale engineering of thin film morphology for efficient organic photovoltaic cells  

NASA Astrophysics Data System (ADS)

Organic photovoltaic cells (OPVs) have received significant industrial and academic interest in the last decade as a promising source of inexpensive renewable energy. However, further improvements in device performance and improved lifetimes are required for the commercialization of OPVs. This work is primarily focused on developing a novel device architecture to improve device performance and characterizing structure-property-performance relationships for OPVs. The excitonic nature of organic semiconductors necessitates the use of an electron donor-acceptor (D-A) heterojunction for efficient exciton dissociation and the generation of photocurrent. In many organic semiconductors, the optical absorption length is much larger than the exciton diffusion length. This trade-off between absorption and exciton diffusion is often overcome by increasing the area of the dissociating D-A interface using engineered film morphologies. This thesis presents an approach to maximize cell efficiency using a continuously graded D-A heterojunction. The graded heterojunction allows for an increase in the D-A interface area for an enhanced exciton diffusion efficiency, while also preserving the charge collection efficiency, leading to a significant improvement in device performance relative to that of optimized planar and uniformly mixed OPVs. In addition, this work correlates the optimized D-A composition gradient to the underlying film morphology and charge transport properties of uniform D-A mixtures. Subsequently, a new characterization technique to calculate the charge collection efficiency of OPVs is discussed. This technique is used to demonstrate the enhanced charge collection efficiency in graded heterojunctions relative to uniformly mixed heterojunctions. Afterwards, the properties of a new material and its potential as an electron donor material in OPVs are examined. Finally, an overview of the results and the ideas for future work are presented.

Pandey, Richa

340

Effects of space mission factors on the morphology and function of endothelial cells.  

PubMed

The structure and functions of endothelial cells after space mission were studied by electron and laser confocal microscopy, image analysis, and MTT test. The endothelial cells changed significantly (proliferative activity, size, contours, shape, distribution of mitochondria and microtubules) in comparison with controls on the Earth. These changes indicated injuries in the cytoskeleton and impairment of the barrier function of the cells, which presumably contributed to the development of endothelial dysfunction. PMID:23658927

Kapitonova, M Yu; Kuznetsov, S L; Froemming, G R A; Muid, S; Nor-Ashikin, M N K; Otman, S; Shahir, A R M; Nawawi, H

2013-04-01

341

A BIOCHEMICAL AND MORPHOLOGIC STUDY OF MYELINATION AND DEMYELINATION  

PubMed Central

Bilateral transection was performed on rat sciatics. At varying intervals after the operation, samples of nerve were taken both distal and proximal to the level of transection, as well as from the tissue which bridged the gap between the stumps. These samples were incubated in Warburg flasks, with glucose and a labelled lipide precursor (acetate or phosphate). The total lipides were then extracted and their radioactivity was measured. Normal rat sciatics served as controls, and the biochemical and histological findings were correlated. In the distal portion undergoing Wallerian degeneration, the lipide content began to fall before any removal of myelin could be detected histologically. It is suggested that there is a period of "non-cellular removal" prior to the physical breakdown of the myelin. Changes in respiration and in lipogenesis from acetate followed a triphasic course, and agreed with the histological findings in that after a period of predominantly passive changes (approximately 1 to 3 days) there follows a period of cellular reaction (4 to 50 days) and a period of atrophy (from 50 days onward). The incorporation of phosphate into the lipides was increased at all stages examined, even as early as 22 hours after section. This increased P32 incorporation could not be reproduced in nerves allowed to degenerate in vitro. It is suggested that the hypertrophying Schwann cells synthesize some lipide moieties at a considerably faster rate than others. Proximal to the level of transection, lipogenesis from acetate was depressed, for as long as 32 days postoperatively. It appears, therefore, that the maintenance of the myelin sheath is impaired also above the level of transection. In the "union tissue" which developed between the stumps, prior to the appearance of histologically visible myelin, lipogenesis was low; later it rose above levels for normal nerve. This pattern of lipogenesis in regenerating nerve is similar to that found in growing nerves. PMID:13563756

Majno, Guido; Karnovsky, Manfred L.

1958-01-01

342

Molecular and morphological studies on the Didymodon tophaceus complex  

Microsoft Academic Search

Recently two Mediterranean species closely related to???Didymodon tophaceus (Brid.) Lisa have been described in the genus Didymodon Hedw.: Didymodon sicculus M. J. Cano et al. and Didymodon erosus J. A. Jiménez & J. Guerra. The former has been proved to be widespread around the Mediterranean basin in recent years, and this study points to a considerable extension of its distribution

O. Werner; H. Köckinger; J. A. Jiménez; R. M. Ros

2009-01-01

343

Morphological transformation and effect on gap junction intercellular communication in Syrian hamster embryo cells as screening tests for carcinogens devoid of mutagenic activity.  

PubMed

A large fraction of chemicals observed to cause cancer in experimental animals is devoid of mutagenic activity. It is therefore of importance to develop methods that can be used to detect and study environmental carcinogenic agents that do not interact directly with DNA. Previous studies have indicated that induction of in vitro cell transformation and inhibition of gap junction intercellular communication are endpoints that could be useful for the detection of non-genotoxic carcinogens. In the present work, 13 compounds [chlordane, Arochlor 1260, di(2-ethylhexyl)phthalate, 1,1,1-trichloro-2, 2-bis(4-chlorophenyl)ethane, limonene, sodium fluoride, ethionine, o-anisidine, benzoyl peroxide, o-vanadate, phenobarbital, 12-O-tetradecanoylphorbol 13-acetate and clofibrate] have been tested for their ability to induce morphological transformation and affect intercellular communication in Syrian hamster embryo cells. The substances were selected on the basis of being proven or suspected non-genotoxic carcinogens, and thus difficult to detect in short-term tests. The data show that nine of the 13 compounds induced morphological transformation, and seven of the 13 inhibited intercellular communication in hamster embryo cells. Taken together, 12 of the 13 substances either induced transformation or caused inhibition of communication. The data suggest that the combined use of morphological transformation and gap junction intercellular communication in Syrian hamster embryo cells may be beneficial when screening for non-genotoxic carcinogens. PMID:10793297

Rivedal, E; Mikalsen, S O; Sanner, T

2000-04-01

344

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

E-print Network

for the increased osmotic fragility of RBCs from patients suffering from spherocytosis. Key Terms: erythrocyte). Poration driven hemolysis is intrinsically dependent on the osmotic fragility of the red blood cells (RBCs, which in turn leads to cell lysis (2). Osmotic fragility itself has been studied extensively

Hughey, Richard

345

Morphology, physiology, and homology of the N-cell and muscle receptor organs in the thorax of the crayfish Cherax destructor.  

PubMed

The serial homology of arthropods, together with our ability to identify individual neurons from segment to segment, and from animal to animal, provides opportunities for studying the changes wrought by natural selection on specific neural elements when functional requirements change in different parts of the trunk. Using this concept as a guide, we studied the morphology and physiology of the thoracic N-cells and muscle receptor organs (MROs) of the crayfish Cherax destructor for evidence of serial homology and functional plasticity. Methylene blue staining, together with anterograde and retrograde filling with cobalt through cut axons, revealed the morphology of the receptors, disposition of their endings, and the pathways of their axons from receptor to ganglion. The seventh thoracic segment has tonic and phasic MROs with receptor muscles in parallel with different heads of the deep thoraco-abdominal extensor muscle. The sixth segment has a tonic MRO with a receptor muscle in parallel with one head of the abdominal abductor. These three receptors are typical MROs complete with accessory nerves. Thoracic segments 1-5 each give rise to one mechanosensory N-cell with a small cell body and long processes ramifying in a target muscle. N-cell 5 is associated with the abdominal-thoracic abductor muscle, and the other four are associated with parts of the epimeral attractor. The responses of N-cells 1-4 range from tonic to phasico-tonic and show a range of thresholds to passive muscle stretch and active contraction. Cobalt introduced into bundles of nerve fibers known to include N-cell axons reveals projections with branching patterns and morphology similar to abdominal MROs. The present findings, together with information on thoracic MROs and N-cells from other species, were tabulated according to neurotome. The clear pattern revealed leads us to propose that N-cells are derivatives of segmentally repeating MROs modified to monitor postural and locomotory movements in the less mobile thorax. PMID:7890831

MacMillan, D L; Field, L H

1994-12-22

346

Predicting the morphology of sickle red blood cells using coarse-grained models of intracellular aligned hemoglobin polymers†  

PubMed Central

Sickle red blood cells (SS-RBCs) exhibit heterogeneous cell morphologies (sickle, holly leaf, granular, etc.) in the deoxygenated state due to the polymerization of the sickle hemoglobin. Experimental evidence points to a close relationship between SS-RBC morphology and intracellular aligned hemoglobin polymers. Here, we develop a coarse-grained (CG) stochastic model to represent the growth of the intracellular aligned hemoglobin polymer domain. The CG model is calibrated based on the mechanical properties (Young’s modulus, bending rigidity) of the sickle hemoglobin fibers reported in experiments. The process of the cell membrane transition is simulated for physiologic aligned hemoglobin polymer configurations and mean corpuscular hemoglobin concentration. Typical SS-RBC morphologies observed in experiments can be obtained from the current model as a result of the intracellular aligned hemoglobin polymer development without introducing any further ad hoc assumptions. It is found that the final shape of SS-RBCs is primarily determined by the angular width of the aligned hemoglobin polymer domain, but it also depends, to a lesser degree, on the polymer growth rate and the cell membrane rigidity. Cell morphologies are quantified by structural shape factors, which agree well with experimental results from medical images. PMID:24307912

Lei, Huan; Karniadakis, George Em

2013-01-01

347

Morphology and adhesion strength of myoblast cells on photocurable gelatin under native and non-native micromechanical environments.  

PubMed

We have quantitatively determined how the morphology and adhesion strength of myoblast cells can be regulated by photocurable gelatin gels, whose mechanical properties can be fine-tuned by a factor of 10(3) (0.1 kPa ? E ? 140 kPa). The use of such gels allows for the investigation of mechanosensing of cells not only near the natural mechanical microenvironments (E ~ 10 kPa) but also far below and beyond of the natural condition. Optical microscopy and statistical image analysis revealed that myoblast cells sensitively adopt their morphology in response to the substrate elasticity at E ~ 1-20 kPa, which can be characterized by the significant changes in the contact area and order parameters of actin cytoskeletons. In contrast, the cells in contact with the gels with lower elastic moduli remained almost round, and the increase in the elasticity beyond E ~ 20 kPa caused no distinct change in morphology. In addition to the morphological analysis, the adhesion strength was quantitatively evaluated by measuring the critical detachment pressure with an aid of intensive pressure waves induced by picosecond laser pulses. This noninvasive technique utilizing extremely short pressure waves (pulse time width ~100 ns) enables one to determine the critical pressure for cell detachment with reliable statistics while minimizing the artifacts arising from the inelastic deformation of cells. The adhesion strength also exhibited a transition from weak adhesion to strong adhesion within the same elasticity range (E ~ 1-20 kPa). A clear correlation between the cell morphology and adhesion strength suggests the coupling of the strain of the substrate and the mechanosensors near focal adhesion sites. PMID:23531225

Yoshikawa, Hiroshi Y; Kawano, Takahito; Matsuda, Takehisa; Kidoaki, Satoru; Tanaka, Motomu

2013-04-18

348

AFM studies of surface morphologies of sputtered SrTiO3 films and annealed MgO substrates  

Microsoft Academic Search

Atomic force microscopy (AFM) is applied to study the surface morphologies and growth mechanisms of sputtered SrTiO3 films on single-crystal MgO(100) substrates. Meanwhile, surface morphologies of as-polished and post-annealed MgO(100) substrates are investigated as well. Effects of the miscut (or misorientation) of the substrate surface on morphologies and growth mechanisms are discussed. For comparison, a typical surface morphology and growth

Q. Meng; R. Moerman; A. H. Sonnenberg; G. J. Gerritsma

1999-01-01

349

Pars flaccida perforation in tissue culture: morphological study.  

PubMed

Subtotal pars flaccida perforation was effected in vitro in rat tympanic membranes. The drums were subsequently kept in tissue culture and after various intervals studied by means of light and scanning electron microscopy. No complete covering of the perforation was seen, though a marked thickening and hyperplasia of the outer, keratinizing, squamous epithelium (OE) was evident. The inner, tympanal epithelium (IE) appeared swollen, containing rounded structures in the cytoplasm especially close to the contact area with the OE. Ingrowth of OE onto the tympanal side of the drum was seen particularly in the areas where the IE was sparse and completely lacking. Complete covering of a drum perforation seems to be dependent on the formation of supporting granulation tissue, probably resulting from an inflammatory reaction in the healing area. PMID:2324630

Stenfors, L E; Olsen, E G; Henriksen, A O

1990-02-01

350

Resampling-Based Approaches to Study Variation in Morphological Modularity  

PubMed Central

Modularity has been suggested to be connected to evolvability because a higher degree of independence among parts allows them to evolve as separate units. Recently, the Escoufier RV coefficient has been proposed as a measure of the degree of integration between modules in multivariate morphometric datasets. However, it has been shown, using randomly simulated datasets, that the value of the RV coefficient depends on sample size. Also, so far there is no statistical test for the difference in the RV coefficient between a priori defined groups of observations. Here, we (1), using a rarefaction analysis, show that the value of the RV coefficient depends on sample size also in real geometric morphometric datasets; (2) propose a permutation procedure to test for the difference in the RV coefficient between a priori defined groups of observations; (3) show, through simulations, that such a permutation procedure has an appropriate Type I error; (4) suggest that a rarefaction procedure could be used to obtain sample-size-corrected values of the RV coefficient; and (5) propose a nearest-neighbor procedure that could be used when studying the variation of modularity in geographic space. The approaches outlined here, readily extendable to non-morphometric datasets, allow study of the variation in the degree of integration between a priori defined modules. A Java application – that will allow performance of the proposed test using a software with graphical user interface – has also been developed and is available at the Morphometrics at Stony Brook Web page (http://life.bio.sunysb.edu/morph/). PMID:23874956

Fruciano, Carmelo; Franchini, Paolo; Meyer, Axel

2013-01-01

351

Malignant rhabdoid tumor. A morphological and flow cytometric study.  

PubMed

Sixteen cases of malignant rhabdoid tumor (MRT) were studied by conventional light microscopy, immunohistochemistry, electron microscopy and flow cytometry. The age of the 16 patients varied from two months to 25.9 years. There were 11 males and five females. Eleven tumors were located in the kidney. The remaining five were found in the chest wall (n = 2) and the head and neck (n = 3). Particular histopathological findings included myxoid, pseudoalveolar and hyalinized areas. By immunohistochemistry, 15/15 cases stained positively for vimentin, 9/14 for cytokeratin, 6/15 for desmin, 9/14 for epithelial membrane antigen (EMA), 10/14 for neuron specific enolase (NSE) and 10/15 for protein S-100. Stains for neurofilaments, myoglobin and Ulex europaeus aggl. I (UEA I) were negative. The characteristic finding by electron microscopy in three cases were large numbers of intermediate filaments arranged either randomly or in concentric whorls. None of the 11 cases studied revealed aneuploid DNA stem lines as determined by flow cytometry. Of the 16 patients 12 died, one is living with disease and three are living without evidence of disease. Postoperative treatment consisted of chemotherapy, in some cases combined with radiotherapy. Two patients developed a medulloblastoma in addition to a renal and extrarenal MRT, respectively. Our findings demonstrate that MRT may present more histopathological patterns than hitherto recognized. In addition, they show that MRT may express a wide range of antigenic "markers", similar to epithelioid sarcoma with which it may be confused on cytological grounds. Despite aggressive postoperative chemotherapy prognosis is still poor. PMID:2469068

Schmidt, D; Leuschner, I; Harms, D; Sprenger, E; Schäfer, H J

1989-02-01

352

In-depth morphological study of mesiobuccal root canal systems in maxillary first molars: review  

PubMed Central

A common failure in endodontic treatment of the permanent maxillary first molars is likely to be caused by an inability to locate, clean, and obturate the second mesiobuccal (MB) canals. Because of the importance of knowledge on these additional canals, there have been numerous studies which investigated the maxillary first molar MB root canal morphology using in vivo and laboratory methods. In this article, the protocols, advantages and disadvantages of various methodologies for in-depth study of maxillary first molar MB root canal morphology were discussed. Furthermore, newly identified configuration types for the establishment of new classification system were suggested based on two image reformatting techniques of micro-computed tomography, which can be useful as a further 'Gold Standard' method for in-depth morphological study of complex root canal systems. PMID:23493453

Chang, Seok-Woo; Lee, Jong-Ki; Lee, Yoon

2013-01-01

353

[HPV infection: comparison between morphological studies and molecular biology].  

PubMed

Human Papilloma Virus plays an essential role in the development of cervical cancer. We investigated the global prevalence of Human Papilloma Virus infection in a population of 699 women recruited at the Ospedali Riuniti in Foggia for gynaecological controls from September 2005 to March 2007, and compared with a group of 90 women, selected on clinical aspects for Human Papilloma Virus features. The observed prevalence was 27.4%, which is higher that that reported in the literature. In the study group, the most frequent viral type was 16, while type 18 was considerably less frequent compared with other emergent viral types (39, 52, 56, 58, 59). The high prevalence of Human Papilloma Virus-DNA in women with negative cytology or inflammatory changes raises doubts about the utility of the Human Papilloma Virus-DNA method as a primary screening test because of the low cost/benefit ratio. The absence of uniform and standardised reports does not allow objective comparison between different methods of analysis (cytology, colposcopy and molecular biology), pointing out the need for a unique centre for collection and data analysis. PMID:18841817

Nirchio, V; Lipsi, R; Fusilli, S; Ciccone, E; Murino, L; Santangelo, A; Romano, F; Di Taranto, A M; Pedà, D; Castriota, M; Antonetti, R; Bondi, A

2008-06-01

354

Morphological and physiological studies on Indian national kabaddi players.  

PubMed Central

Twenty-five national kabaddi players (Asiad gold medalists 1990), mean age 27.91 years, who attended a national camp at the Sports Authority of India, Bangalore before the Beijing Asian Games in 1990, were investigated for their physical characteristics, body fat, lean body mass (LBM) and somatotype. The physiological characteristics assessed included back strength, maximum oxygen uptake capacity and anaerobic capacity (oxygen debt) and related cardiorespiratory parameters (oxygen pulse, breathing equivalent, maximum pulmonary ventilation, maximum heart rate). Body fat was calculated from skinfold thicknesses taken at four different sites, using Harpenden skinfold calipers. An exercise test (graded protocol) was performed on a bicycle ergometer (ER-900) using a computerized EOS Sprint (Jaeger, West Germany). The mean(s.d.) percentage body fat (17.56(3.48)) of kabaddi players was found to be higher than normal sedentary people. Their physique was found to be endomorphic mesomorph (3.8-5.2-1.7). Mean(s.d.) back strength, maximum oxygen uptake capacity (VO2max) and oxygen debt were found to be 162.6(18.08) kg, 42.6(4.91) ml kg-1 min-1 and 5.02(1.29) litre respectively. Physical characteristics, percentage body fat, somatotype, maximum oxygen uptake capacity and anaerobic capacity (oxygen debt) and other cardiorespiratory parameters were compared with other national counterparts. Present data are comparable with data for judo, wrestling and weightlifting. Since no such study has been conducted on international counterparts, these data could not be compared. These data may act as a guideline in the selection of future kabaddi players and to attain the physiological status comparable to the present gold medalists. Images Figure 4 Figure 5 p242-a PMID:8130960

Dey, S K; Khanna, G L; Batra, M

1993-01-01

355

Immunoenzymatic and morphological detection of epithelial cell apoptotic stages in gastrointestinal allografts from multivisceral transplant patients.  

PubMed

Acute allograft rejection (AR) is a major contributor to morbidity and mortality among patients who undergo multivisceral transplantation. Critical to the assessment of AR is detection of apoptosis in the glandular epithelium of the gastrointestinal allograft. We utilized the TUNEL stain (TdT-mediated biotin 16-dUTP nick-end labeling) to test whether this method improved detection of apoptosis compared to standard slide evaluation. TUNEL and H&E stains were performed on paraffin-embedded tissue sections to estimate the number of apoptotic bodies per 10 high power fields, as determined by independent pathologists in blinded fashion. Both methodologies showed similar numbers and distributions of apoptotic foci present among the epithelial cells. There was a correlation between the number of apoptosis and the grade of rejection (P <.001). This is the first use of the TUNEL stain in gastrointestinal allograft biopsies to our knowledge. The similarity in pattern and sensitivity of TUNEL with standard morphology confirms that biopsy assessment with routine H&E staining allows an accurate appraisal of epithelial cell apoptosis. Therefore, current staining protocols for endoscopically derived mucosal biopsies of gastrointestinal allografts are sufficiently accurate to enumerate the critical feature of epithelial apoptosis as a determinant of the grade of acute rejection. PMID:15050151

Delacruz, V; Garcia, M; Mittal, N; Nishida, S; Levi, D; Selvaggi, G; Madariaga, J; Weppler, D; Tzakis, A; Ruiz, P

2004-03-01

356

Longitudinal imaging studies in schizophrenia: the relationship between brain morphology and outcome measures.  

PubMed

Imaging studies have tried to identify morphological outcome measures of schizophrenia in the last two decades. In particular, longitudinal studies have reported a correlation between larger ventricles, decreased prefrontal volumes and worse outcome. This would potentially allow to isolate subtypes of schizophrenia patients with a worse prognosis and more evident biological impairments, ultimately helping in designing specific rehabilitation interventions. PMID:21261215

Bellani, Marcella; Dusi, Nicola; Brambilla, Paolo

2010-01-01

357

Eco-morphological studies on pleopodal lungs and cuticle in Armadillidium species (Crustacea, Isopoda, Oniscidea).  

PubMed

Terrestrial isopods (Crustacea, Isopoda, Oniscidea) have adapted to land life by diverse morphological, physiological and behavioral changes. Woodlice species exhibit a large variety in this respect, their preferences ranging from moist to dry habitats. These moisture preference values are related to various morphological adaptations, rendering terrestrial isopods amenable to studying morphological adaptations to terrestrial life. We performed a comparison of four Armadillidium species (Armadillidium zenckeri, Armadillidium nasatum, Armadillidium versicolor, Armadillidium vulgare), by quantifying two morphological traits: the extent of the interfacial endothelium between the respiratory space and the hemolymph within pleopodal lungs and the thickness of tergite cuticle, which are 'key factors' in determining protection from desiccation. These values were measured from light micrographs of cross-sectioned lungs. The cosmopolitan A. vulgare, as a habitat generalist, seems to be the most resistant against desiccation and other environmental conditions, while A. zenckeri is the most sensitive one. Light microscopic studies revealed that the four species can be ordered similarly, if we compare them by the extension of the endothelial interface and cuticle thickness, suggesting that these morphological traits are important determinants of their distribution on habitat, microhabitat scales and through the existence of suitable habitats - together with many other factors - the geographical pattern of species occurence. PMID:23376766

Csonka, Diána; Halasy, Katalin; Szabó, Péter; Mrak, Polona; Strus, Jasna; Hornung, Elisabeth

2013-05-01

358

Porous poly( l-lactide) films obtained by immersion precipitation process: morphology, phase separation and culture of VERO cells  

Microsoft Academic Search

In this work, the immersion precipitation process was used to obtain porous poly(l-lactide) films which were tested as supports for culture of VERO cells. The mechanism of phase separation taking place during the film formation was investigated using light scattering measurements. A theoretical ternary phase diagram was proposed and correlated with the light scattering results. The film morphology was investigated

R. A Zoppi; S Contant; E. A. R Duek; F. R Marques; M. L. F Wada; S. P Nunes

1999-01-01

359

N-NITROSODIETHYLAMINE AND 4-(METHYLNITROSAMINO)-1-(3-PYRIDYL)-1-BUTANONE INDUCED MORPHOLOGICAL TRANSFORMATION OF CH3/10T1/2CL8 CELLS EXPRESSING HUMAN CYTOCHROME P450 2A6  

EPA Science Inventory

Transfection of specific genes into cells capable of expressing chemically-induced morphological cell transformation provides a valuable approach to study the mechanisms of action of carcinogens. uman cytochrome P450 isozyme, CYP2A6, has been successfully expressed from a retrovi...

360

Naphtho[2,1-b:3,4-b']dithiophene-based Bulk Heterojunction Solar Cells: How Molecular Structure Influences Nanoscale Morphology and Photovoltaic Properties.  

PubMed

Organic bulk heterojunction photovoltaic devices based on a series of three naphtho[2,1-b:3,4-b']dithiophene (NDT) derivatives blended with phenyl-C71 -butyric acid methyl ester were studied. These three derivatives, which have NDT units with various thiophene-chain lengths, were employed as the donor polymers. The influence of their molecular structures on the correlation between their solar-cell performances and their degree of crystallization was assessed. The grazing-incidence angle X-ray diffraction and atomic force microscopy results showed that the three derivatives exhibit three distinct nanoscale morphologies. We correlated these morphologies with the device physics by determining the J-V characteristics and the hole and electron mobilities of the devices. On the basis of our results, we propose new rules for the design of future generations of NDT-based polymers for use in bulk heterojunction solar cells. PMID:25145537

Kim, Yu Jin; Cheon, Ye Rim; Back, Jang Yeol; Kim, Yun-Hi; Chung, Dae Sung; Park, Chan Eon

2014-11-10

361

Dickkopf-3 alters the morphological response to retinoic acid during neuronal differentiation of human embryonal carcinoma cells.  

PubMed

Dickkopf-3 (Dkk-3) and Dkkl-1 (Soggy) are secreted proteins of poorly understood function that are highly expressed in subsets of neurons in the brain. To explore their potential roles during neuronal development, we examined their expression in Ntera-2 (NT2) human embryonal carcinoma cells, which differentiate into neurons upon treatment with retinoic acid (RA). RA treatment increased the mRNA and protein levels of Dkk-3 but not of Dkkl-1. Ectopic expression of both Dkk-3 and Dkkl-1 induced apoptosis in NT2 cells. Gene silencing of Dkk-3 did not affect NT2 cell growth or differentiation but altered their response to RA in suspension cultures. RA treatment of NT2 cells cultured in suspension resulted in morphological changes that led to cell attachment and flattening out of cell aggregates. Although there were no significant differences in the expression levels of cell adhesion molecules in control and Dkk-3-silenced cells, this morphological response was not observed in Dkk-3-silenced cells. These findings suggest that Dkk-3 plays a role in the regulation of cell interactions during RA-induced neuronal differentiation. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 74: 1243-1254, 2014. PMID:24909558

Alfonso, Rocío Jiménez; Gorroño-Etxebarria, Irantzu; Rabano, Miriam; Vivanco, Maria dM; Kypta, Robert

2014-12-01

362

Ion dynamics in cells — preparation for studies of intracellular processes  

NASA Astrophysics Data System (ADS)

A proton beam of about 1 ?m allows the study of inner structures of cells. These studies demand sophisticated preparation methods, not to destroy the morphology or the elemental distribution. Analysing a well-preserved cell may lead to important knowledge about basic regulatory processes at the cellular level. Freezing followed by removal of water by drying or by substitution with an organic solvent will be exemplified. Insulin-producing cells were studied to reach a further understanding of the signal transduction between stimulation to secrete insulin and the secretion.

Pålsgård, Eva; Roomans, Godfried; Lindh, Ulf

1995-09-01

363

Study of the formation of the open-cellular morphology of poly(styrene\\/divinylbenzene) polyHIPE materials by cryo-SEM  

Microsoft Academic Search

The formation of the interconnected morphology of open-cell styrene\\/divinylbenzene (DVB) PolyHIPE copolymers has been studied by scanning electron microscopy on frozen HIPE samples at different stages of polymerisation, a technique known as cryo-SEM. The transition from discrete emulsion droplets to interconnected cells was observed to occur around the gelpoint of the polymerising system. This would suggest that the formation of

N. R. Cameron; D. C. Sherrington; L. Albiston; D. P. Gregory

1996-01-01

364

Morphological and molecular changes of human granulosa cells exposed to 5-azacytidine and addressed toward muscular differentiation.  

PubMed

Converting adult cells from one cell type to another is a particularly interesting idea for regenerative medicine. Terminally differentiated cells can be induced to de-differentiate in vitro to become multipotent progenitors. In mammals these changes do not occur naturally, however exposing differentiated adult cells to synthetic molecules capable of selectively reverting cells from their lineage commitment to a more plastic state makes it possible to re-address their fate. Only scattered information are available on the morphological changes and ultrastructural remodeling taking place when cells convert into a different and specific type. To better clarify these aspects, we derived human granulosa cell (GC) primary cultures and analyzed the morphological changes taking place in response to the exposure to the epigenetic modifier 5-azacytidine (5-aza-CR) and to the treatment with VEGF, as a stimulus for inducing differentiation into muscle cells. Ultrastructural modifications and molecular marker expression were analyzed at different intervals during the treatments. Our results indicate that the temporary up regulation of pluripotency markers is accompanied by the loss of GC-specific ultrastructural features, mainly through autophagocitosis, and is associated with a temporary chromatin decondensation. After exposure to VEGF the induction of muscle specific genes was combined with the appearance of multinucleated cells with a considerable quantity of non-spatially organized filaments. The detailed analysis of the morphological changes occurring in cells undergoing lineage re-addressing allows a better understanding of these process and may prove useful for refining the use of somatic cells in regenerative medicine and tissue replacement therapies. PMID:24858410

Brevini, Tiziana A L; Pennarossa, Georgia; Rahman, Mahbubur M; Paffoni, Alessio; Antonini, Stefania; Ragni, Guido; deEguileor, Magda; Tettamanti, Gianluca; Gandolfi, Fulvio

2014-10-01

365

[Diverse morphological types of dormant cells and conditions for their formation in Azospirillum brasilense].  

PubMed

Differences in generation of dormant forms (DF) were revealed between two strains of non-sporeforming gram-negative bacteria Azospirillum brasilense, Sp7 (non-endophytic) and Sp245 (endophytic strain). In post-stationary ageing bacterial cultures grown in a synthetic medium with a fivefold decreased initial nitrogen content, strain Sp7 formed two types of cyst-like resting cells (CRC). Strain Sp245 did not form such types of DF under the same conditions. CRC of the first type were formed in strain Sp245 only under phosphorus deficiency (C > P). The endophytic strain was also shown to form structurally differentiated cells under complete starvation, i.e. at a transfer of early stationary cultures, grown in the media with C > N unbalance, to saline solution (pH 7.2). These DF had a complex structure similar to that of azotobacter cysts. The CRC, which are generated by both azospirilla strains and belong to distinct morphological types, possessed the following major features: absence of division; specific ultrastructural organization; long-term maintenance of viability (for 4 months and more); higher heat resistance (50-60 degrees C, 10 min) as compared with vegetative cells, i.e. the important criteria for dormant prokaryotic forms. However, CRC of non-endophytic strain Sp7 had higher heat resistance (50, 55, 60 degrees C). The viability maintenance and the portion of heat-resistant cells depended on the conditions of maturation and storage of CRC populations. Long-term storage (for 4 months and more) of azospirilla DF populations at -20 degrees C was optimal for maintenance of their colony-forming ability (57% of the CFU number in stationary cultures), whereas the largest percentage of heat-resistant cells was in CRC suspensions incubated in a spent culture medium (but not in saline solution) at room temperature. The data on the intraspecies diversity of azospirilla DF demonstrate the relation between certain type DF formation to the type of interaction (non-endophytic or endophytic) with the plant partner and provide more insight into the adaptation mechanisms that ensure the survival of gram-negative non-spore-forming bacteria in nature. PMID:19334596

Muliukin, A L; Suzina, N E; Pogorelova, A Iu; Antoniuk, L P; Duda, V I; El'-Registan, G I

2009-01-01

366

Altered pancreatic islet function and morphology in mice lacking the Beta-cell surface protein neuroligin-2.  

PubMed

Neuroligin-2 is a transmembrane, cell-surface protein originally identified as an inhibitory synapse-associated protein in the central nervous system. Neuroligin-2 is also present on the pancreatic beta-cell surface, and there it engages in transcellular interactions that drive functional maturation of the insulin secretory machinery; these are necessary for normal insulin secretion. The effects of neuroligin-2 deficiency on brain and neuronal function and morphology and on behavior and coordination have been extensively characterized using neuroligin-2 knockout mice. The effects of absent neuroligin-2 expression on islet development and function, however, are unknown. Here, to help test whether neuroligin-2 is necessary for normal islet development, we characterized islet morphology in mice lacking neuroligin-2. To test whether-as predicted by our earlier co-culture studies-absence of neuroligin-2 impairs beta cell function, we compared glucose-stimulated insulin secretion by islets from mutant and wild-type mice. Our results show that while islets from neuroligin-2-deficient mice do not to appear to differ architecturally from wild-type islets, they are smaller, fewer in number, and contain beta cells with lower insulin content. Evaluation of transcript levels suggests that upregulation of neuroligin-1 helps compensate for loss of neuroligin-2. Surprisingly, under both basal and stimulating glucose levels, isolated islets from the knockout mice secreted more of their intracellular insulin content. Rat islets with shRNA-mediated neuroligin-2 knockdown also exhibited increased insulin secretion. Neurexin transcript levels were lower in the knockout mice and, consistent with our prior finding that neurexin is a key constituent of the insulin granule docking machinery, insulin granule docking was reduced. These results indicate that neuroligin-2 is not necessary for the formation of pancreatic islets but that neuroligin-2 influences islet size and number. Neuroligin-2-perhaps through its effects on the expression and/or activity of its binding partner neurexin-promotes insulin granule docking, a known constraint on insulin secretion. PMID:23776533

Zhang, Charles; Suckow, Arthur T; Chessler, Steven D

2013-01-01

367

Combining multiobjective optimization and cluster analysis to study vocal fold functional morphology.  

PubMed

Morphological design and the relationship between form and function have great influence on the functionality of a biological organ. However, the simultaneous investigation of morphological diversity and function is difficult in complex natural systems. We have developed a multiobjective optimization (MOO) approach in association with cluster analysis to study the form-function relation in vocal folds. An evolutionary algorithm (NSGA-II) was used to integrate MOO with an existing finite element model of the laryngeal sound source. Vocal fold morphology parameters served as decision variables and acoustic requirements (fundamental frequency, sound pressure level) as objective functions. A two-layer and a three-layer vocal fold configuration were explored to produce the targeted acoustic requirements. The mutation and crossover parameters of the NSGA-II algorithm were chosen to maximize a hypervolume indicator. The results were expressed using cluster analysis and were validated against a brute force method. Results from the MOO and the brute force approaches were comparable. The MOO approach demonstrated greater resolution in the exploration of the morphological space. In association with cluster analysis, MOO can efficiently explore vocal fold functional morphology. PMID:24771563

Palaparthi, Anil; Riede, Tobias; Titze, Ingo R

2014-07-01

368

The activation of proteinase-activated receptor-1 (PAR1) promotes gastric cancer cell alteration of cellular morphology related to cell motility and invasion.  

PubMed

Cell motility proceeds by cycles of edge protrusion, adhesion and retraction. Whether these functions are coordinated by biochemical or biomechanical processes is unknown. Tumor invasion and metastasis is directly related to cell motility. We showed that stimulation of proteinase-activated receptor-1 (PAR1) can trigger an array of responses that would promote tumor cell growth and invasion. Thus, we examined aspects of PAR1 activation related to cell morphological change that might contribute to cell motility. We established a PAR1 stably transfected MKN45 gastric cancer cell line (MKN45/PAR1). We examined morphological changes, Rho family activation and overexpression of cytoskeletal protein in cells exposed to PAR1 agonists (?-thrombin and TFLLR-NH2). MKN45/PAR1 grows with an elongated and polarized morphology, extending pseudopodia at the leading edge. However, in the presence of PAR1 antagonist, MKN45/PAR1 did not show any changes in cell shape upon addition of either ?-thrombin or TFLLR-NH2. Activated PAR1 induced RhoA and Rac1 phosphorylation, and subsequent overexpression of myosin IIA and filamin B which are stress fiber components that were identified by PMF analysis of peptide mass data obtained by MALDI-TOF/MS measurement. Upon stimulation of MKN45/PAR1 for 24 h with either ?-thrombin or TFLLR-NH2, the distribution of both myosin IIA and filamin B proteins shifted to being distributed throughout the cytoplasm to the membrane, with more intense luminescence signals than in the absence of stimulation. These results demonstrate that PAR1 activation induces cell morphological change associated with cell motility via Rho family activation and cytoskeletal protein overexpression, and has a critical role in gastric cancer cell invasion and metastasis. PMID:23242308

Fujimoto, Daisuke; Hirono, Yasuo; Goi, Takanori; Katayama, Kanji; Matsukawa, Shigeru; Yamaguchi, Akio

2013-02-01

369

Morphological and structural study of ultra thin Al films on polymer substrate  

NASA Astrophysics Data System (ADS)

Processes of nucleation and shaping of nanostructures on polymer substrate were investigated by analysing the morphology and composition of ultra thin metallic films (Al with thickness 20-100 nm). These films were deposited on a polymer (PET) (and for comparative analysis on a quartz glass substrate) by electron beam evaporation in vacuum. XRD, XPS and AFM were employed to study the structural and morphological changes of the films. In parallel the optical transmittance and resistivity of the thin films were registered. It is shown that annealing of the discontinuous films on PET at temperatures close to the polymer glassing temperature brings about the formation of a transient nanocomposite layer.

Prosy?evas, I.; Tamulevi?ius, S.; Guobien?, A.; ?yži?t?, B.; Iljinas, A.; Andrulevi?ius, M.

2004-07-01

370

Orientation and Morphology of Calcite Nucleated under Floating Monolayers: A Magnesium-ion-enhanced Nucleation Study  

SciTech Connect

We have studied the biomimetic growth of calcium carbonate crystals under floating monolayer templates, in the presence of Mg ions, using grazing incidence X-ray diffraction and SEM imaging. Crystals grown under sulfate monolayers nucleate from the (0 0 1) plane with and without Mg ions, while undergoing substantial changes in morphology. Crystals grown under alcohol monolayers nucleate from the (1 0 4) plane in the presence of Mg. X-ray data do not detect orientation in crystals grown under acid monolayers, but at higher Mg concentrations the resulting morphologies are indicative of template-nucleated growth. These results suggest that Mg provides living organisms a way to enhance the orientation and control the morphology of acid-templated crystals.

B Stripe; A Uysal; P Dutta

2011-12-31

371

Experimental Artifacts for Morphological Tweaking of Chemical Sensor Materials: Studies on ZnO  

PubMed Central

Sensing mechanisms of gases on solid structures are predominantly surface-dominated. Benign surface features in terms of small grain size, high aspect ratio, large surface area and open and connected porosity, are required to realize a successful sensor material. Such morphological artifacts are a function of the fabrication and processing techniques employed. In this paper, we describe the fabrication of monoshaped and monosized zinc oxide (ZnO) particles by a homogeneous precipitation method, using urea and/or hexmethyltetraamine as the reductant. The effect of operating conditions and experimental variables, such as the relative concentration of the precursors, temperature, and the aging time on the morphology of the resulting particles was studied systematically. These experimental parameters were optimized in order to achieve particles of uniform morphology and of narrow size distribution. Some of these particles were employed for the detection of ammonia gas at room temperature. PMID:22969399

Haq, Ikram Ul; Azad, Abdul-Majeed

2012-01-01

372

Fundamental studies of copper anode passivation during electrorefining: Part II. Surface morphology  

NASA Astrophysics Data System (ADS)

Passivation of commercial copper anodes and pure copper has been previously analyzed by performing electrochemical measurements. Chronopotentiometry results revealed four characteristic regions involving I—active dissolution, II—prepassivation, III—passivation onset, and IV—passivation, for commercial copper anodes, while only active dissolution was observed for pure copper under the conditions employed. In order to establish the relationship between surface morphology and passivation response, scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS) were applied to characterize morphology of the product layers formed on a commercial copper anode surface for the distinctive electrochemical regions. The morphology studies suggested that the formation and stability of copper oxide surface films are critical to the onset and development of passivation. The structure and porosity of the slimes layer present in the outer layer of the anode influence the stability of copper oxide surface films which dominantly control the passivation response.

Cheng, Xuan; Hiskey, J. Brent

1996-08-01

373