Morphological characteristics of selenium-polyethylene glycol nanocomposites

2015 ◽  
Vol 89 (9) ◽  
pp. 1625-1627 ◽  
Author(s):  
A. I. Kipper ◽  
A. V. Titova ◽  
L. N. Borovikova ◽  
O. A. Pisarev
Author(s):  
W. A. Shannog ◽  
M. A. Matlib ◽  
J. B. Robinson ◽  
M. Hochli ◽  
P. A. Srere

Toluene has been used to make various cells permeable to exogenous substrates. More recently we have extended the method to heart and liver mitochondria (1,2). We reduced the toluene concentration and included 8.5% polyethylene glycol (PEG) to stabilize these organelles (1).In this study, liver and heart isolated mitochondria and hepatoma type cells (HTC cells) in PEG were treated with either 2% or 0.1% toluene, respectively. The HTC cells were in a solution of 10% PEG, the optimal concentration indicated by biochemical data. The mitochondria were fixed in suspension in 3% glutaraldehyde in 0.1 M phosphate buffer (pH 7.3). It was necessary to add 50% gl utaral dehyde to the HTC cells in PEG-buffer to give a final 3% concentration in order to prevent gross morphological degradation determined to be a result of aqueous glutaraldehyde fixation. Following treatment, specimens were post-fixed in 1% OsO4 and prepared for electron microscopy (1,2).


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Roya Yadollahi ◽  
Krasimir Vasilev ◽  
Clive A. Prestidge ◽  
Spomenka Simovic

The aim of the present research is to formulate and evaluate polymeric nanosuspensions containing three model water insoluble drugs, nifedipine (NIF), carbamazepine (CBZ), and ibuprofen (IBU) with various physicochemical properties. The nanosuspensions were prepared from hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP) by a cosolvent technique with polyethylene glycol (PEG-300) and water as the cosolvents. Physicochemical and morphological characteristics of the nanosuspensions (particle size, polydispersity index, and crystallinity) have been correlated with the drug release behaviour. The effects of polymer, drug ratio on the physical, morphological, and dissolution characteristics of the drugs are reported. Drug release is significantly enhanced from the nanosuspensions; for example, the maximum NIF, IBU, and CBZ concentrations after 8-hour dissolution are increased approximately 37, 2, and 1.2 times, respectively, in comparison with the pure powdered drugs. Based on this solubilization enhancement performance, the nanosuspensions have potential for increasing the orally dosed bioavailability of NIF, IBU, and CBZ.


2016 ◽  
Vol 869 ◽  
pp. 303-307 ◽  
Author(s):  
Raimundo Miguel da Silva Jr. ◽  
Isaias Damasceno Conceição ◽  
João Emídio da Silva Neto ◽  
Tatianny Soares Alves ◽  
Renata Barbosa

In this study, it was investigated the structural and morphological characteristics of bionanocomposites of poly (3-hydroxybutyrate) (PHB), containing 5% polyethylene glycol (PEG), 1% and 3% two types of organoclays (Cloisite 20A and vermiculite). The systems in the form of films were prepared by the method of intercalation solution. The films were characterized by X-ray diffraction (XRD) spectroscopy and Fourier transform infrared (FTIR). It was observed that, according to the type of clay used, the systems showed intercalated structures or partially exfoliated ones. Regarding the FTIR results, they indicated that the addition of different clays to the PHB/PEG blend did not promote significant changes in the chemistry of the polymer matrix.


Author(s):  
M. J. Kramer ◽  
Alan L. Coykendall

During the almost 50 years since Streptococcus mutans was first suggested as a factor in the etiology of dental caries, a multitude of studies have confirmed the cariogenic potential of this organism. Streptococci have been isolated from human and animal caries on numerous occasions and, with few exceptions, they are not typable by the Lancefield technique but are relatively homogeneous in their biochemical reactions. An analysis of the guanine-cytosine (G-C) composition of the DNA from strains K-1-R, NCTC 10449, and FA-1 by one of us (ALC) revealed significant differences and DNA-DNA reassociation experiments indicated that genetic heterogeneity existed among the three strains. The present electron microscopic study had as its objective the elucidation of any distinguishing morphological characteristics which might further characterize the respective strains.


Author(s):  
N. Savage ◽  
A. Hackett

A cell line, UC1-B, which was derived from Balb/3T3 cells, maintains the same morphological characteristics of the non-transformed parental culture, and shows no evidence of spontaneous virus production. Survey by electron microscopy shows that the cell line consists of spindle-shaped cells with no unusual features and no endogenous virus particles.UC1-B cells respond to Moloney leukemia virus (MLV) infection by a change in morphology and growth pattern which is typical of cells transformed by sarcoma virus. Electron microscopy shows that the cells are now variable in shape (rounded, rhomboid, and spindle), and each cell type has some microvilli. Virtually all (90%) of the cells show virus particles developing at the cell surface and within the cytoplasm. Maturing viruses, typical of the oncogenic viruses, are found along with atypical tubular forms in the same cell.


Author(s):  
Kuixiong Gao ◽  
Randal E. Morris ◽  
Bruce F. Giffin ◽  
Robert R. Cardell

Several enzymes are involved in the regulation of anabolic and catabolic pathways of carbohydrate metabolism in liver parenchymal cells. The lobular distribution of glycogen synthase (GS), phosphoenolpyruvate carboxykinase (PEPCK) and glycogen phosphorylase (GP) was studied by immunocytochemistry using cryosections of normal fed and fasted rat liver. Since sections of tissue embedded in polyethylene glycol (PEG) show good morphological preservation and increased detectability for immunocytochemical localization of antigenic sites, and semithin sections of Visio-Bond (VB) embedded tissue provide higher resolution of cellular structure, we applied these techniques and immunogold-silver stain (IGSS) for a more accurate localization of hepatic carbohydrate metabolic enzymes.


Author(s):  
Anne F. Bushnell ◽  
Sarah Webster ◽  
Lynn S. Perlmutter

Apoptosis, or programmed cell death, is an important mechanism in development and in diverse disease states. The morphological characteristics of apoptosis were first identified using the electron microscope. Since then, DNA laddering on agarose gels was found to correlate well with apoptotic cell death in cultured cells of dissimilar origins. Recently numerous DNA nick end labeling methods have been developed in an attempt to visualize, at the light microscopic level, the apoptotic cells responsible for DNA laddering.The present studies were designed to compare various tissue processing techniques and staining methods to assess the occurrence of apoptosis in post mortem tissue from Alzheimer's diseased (AD) and control human brains by DNA nick end labeling methods. Three tissue preparation methods and two commercial DNA nick end labeling kits were evaluated: the Apoptag kit from Oncor and the Biotin-21 dUTP 3' end labeling kit from Clontech. The detection methods of the two kits differed in that the Oncor kit used digoxigenin dUTP and anti-digoxigenin-peroxidase and the Clontech used biotinylated dUTP and avidinperoxidase. Both used 3-3' diaminobenzidine (DAB) for final color development.


Author(s):  
Dai Dalin ◽  
Guo Jianmin

Lipid cytochemistry has not yet advanced far at the EM level. A major problem has been the loss of lipid during dehydration and embedding. Although the adoption of glutaraldehyde and osmium tetroxide accelerate the chemical reaction of lipid and osmium tetroxide can react on the double bouds of unsaturated lipid to from the osmium black, osmium tetroxide can be reduced in saturated lipid and subsequently some of unsaturated lipid are lost during dehydration. In order to reduce the loss of lipid by traditional method, some researchers adopted a few new methods, such as the change of embedding procedure and the adoption of new embedding media, to solve the problem. In a sense, these new methods are effective. They, however, usually require a long period of preparation. In this paper, we do research on the fiora nectary strucure of lauraceae by the rapid-embedding method wwith PEG under electron microscope and attempt to find a better method to solve the problem mentioned above.


Author(s):  
Daryl A. Cornish ◽  
George L. Smit

Oreochromis mossambicus is currently receiving much attention as a candidater species for aquaculture programs within Southern Africa. This has stimulated interest in its breeding cycle as well as the morphological characteristics of the gonads. Limited information is available on SEM and TEM observations of the male gonads. It is known that the testis of O. mossambicus is a paired, intra-abdominal structure of the lobular type, although further details of its characteristics are not known. Current investigations have shown that spermatids reach full maturity some two months after the female becomes gravid. Throughout the year, the testes contain spermatids at various stages of development although spermiogenesis appears to be maximal during November when spawning occurs. This paper describes the morphological and ultrastructural characteristics of the testes and spermatids.Specimens of this fish were collected at Syferkuil Dam, 8 km north- west of the University of the North over a twelve month period, sacrificed and the testes excised.


Sign in / Sign up

Export Citation Format

Share Document