Effect of Titania Concentration in Bioglass/TiO2 Nanostructures and Its In Vitro Biological Property Assessment

The identification of the determinants of bacterial interference with non-specific host defences during the early stages of infection is approached rather than attained. Recognizing a relevant biological property (e.g. resistance to phagocytosis) by an in vitro test and associating bacterial surface components with it are relatively easy. Proving causation, however, is usually not completed because the biological test is complex and the surface component(s) act only in situ . Nevertheless, evidence in addition to mere association can be sought to show that a putative determinant is strongly implicated in biological activity. Even then, proving that the biological activity concerned is relevant to infection in vivo , and that the putative determinant is produced there, is often not accomplished. Again, however, distinction can be made between those cases probably relevant in vivo and those only possibly so. Finally, bacteria grown in vitro can be deficient in some of the determinants of pathogenicity expressed during infection, and this situation requires the study of organisms grown in vivo . These points are discussed and then illustrated in a brief survey of the activities of many pathogenic bacteria and a description of recent work on the resistance of gonococci to killing by human serum and phagocytes.

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Improving the degradation behavior and in vitro biological property of nano-hydroxyapatite surface- grafted with the assist of citric acid

Colloids and Surfaces B Biointerfaces ◽

10.1016/j.colsurfb.2016.05.062 ◽

2016 ◽

Vol 146 ◽

pp. 228-234 ◽

Cited By ~ 10

Author(s):

Liuyun Jiang ◽

Lixin Jiang ◽

Chengdong Xiong ◽

Shengpei Su

Keyword(s):

Citric Acid ◽

Biological Property ◽

Degradation Behavior

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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In Vitro Induction of Crystals of MT Protein by Vinblastine-Colcemid in Mouse Spermatids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050676 ◽

1974 ◽

Vol 32 ◽

pp. 132-133

Author(s):

John J. Wolosewick ◽

John H. D. Bryan

Keyword(s):

Endoplasmic Reticulum ◽

Smooth Endoplasmic Reticulum ◽

Nuclear Ring ◽

Rough Er ◽

Distal Direction ◽

In Vitro Induction

Early in spermiogenesis the manchette is rapidly assembled in a distal direction from the nuclear-ring-densities. The association of vesicles of smooth endoplasmic reticulum (SER) and the manchette microtubules (MTS) has been reported. In the mouse, osmophilic densities at the distal ends of the manchette are the organizing centers (MTOCS), and are associated with the SER. Rapid MT assembly and the lack of rough ER suggests that there is an existing pool of MT protein. Colcemid potentiates the reaction of vinblastine with tubulin and was used in this investigation to detect this protein.

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Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053425 ◽

1982 ◽

Vol 40 ◽

pp. 142-145

Author(s):

E. J. Kollar

Keyword(s):

Connective Tissue ◽

Oral Mucosa ◽

Basal Lamina ◽

Functional Derivatives ◽

Specific Source ◽

Dental Epithelium ◽

Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

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Immunoenzymatic demonstration of the simultaneous presence of transferrin, hemopexin and albumin in a same hepatocyte and their ultrastructural localization

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081309 ◽

1978 ◽

Vol 36 (2) ◽

pp. 88-89

Author(s):

M. Kraemer ◽

J. Foucrier ◽

J. Vassy ◽

M.T. Chalumeau

Keyword(s):

Plasma Proteins ◽

Rat Hepatocytes ◽

Ultrastructural Localization ◽

Carrier Proteins ◽

Normal Cells ◽

Adult Rat ◽

Adult Rat Hepatocytes ◽

Monospecific Antisera ◽

Different Levels

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

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Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055448 ◽

1982 ◽

Vol 40 ◽

pp. 520-521

Author(s):

Ann Chidester Van Orden ◽

John L. Chidester ◽

Anna C. Fraker ◽

Pei Sung

Keyword(s):

Electron Microscopy ◽

Corrosion Behavior ◽

Anodic Polarization ◽

Saline Solution ◽

Saturated Calomel Electrode ◽

Physiological Saline ◽

X Ray ◽

Physiological Saline Solution ◽

Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

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Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053711 ◽

1982 ◽

Vol 40 ◽

pp. 210-211

Author(s):

M.J. Murphy ◽

R.R. Price ◽

J.C. Sloman

Keyword(s):

Cultured Cells ◽

Human Tumor ◽

Cell Type ◽

Tumor Mass ◽

Initial Cell ◽

Cloning Assay ◽

Human Tumor Cloning ◽

The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

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