scholarly journals Regeneration of experimental long bone defect after implantation in its cavity of osteoplastic material “Calc-i-oss®”

2016 ◽  
Vol 33 (02) ◽  
pp. 099-102
Author(s):  
O. Korenkov
Keyword(s):  
Bone Tissue ◽  
Morphological Characteristics ◽  
Compact Bone ◽  
Long Bone ◽  
Electron Microscopic ◽  
Time In Literature ◽  
Microscopic Features ◽  
Definition Of ◽  
Osteoplastic Material ◽  
Long Bone Defect

Abstract Introduction: There is a significant divergence of data on the rate of resorption and replacement by the bone tissue of osteoplastic materials based on β-tricalcium phosphate in cancellous bone. At the same time in literature missing morphometric and electron microscopic features of bone tissue of the regenerate of compact substance of bone in these conditions. This study was aimed at the assessment of the healing of compact bone tissue defect after implantation of osteoplastic material “Calc-i-oss®” with the definition of the dynamics of resorption and morphological characteristics of bone tissue of the regenerate. Material and Methods: In the middle third of the diaphysis of the femur of rats there was reproduced the perforated defect to the bone-brain channel that was filled with osteoplastic material “Calc-i-oss®”. After surgery the fragments of injured bones were studied at the 60th and 120th day by methods of light microscopy with morphometry and scanning electron microscopy. Results: The conducted research revealed no inflammatory reaction at the site of the defect, signs of necrobiosis and necrosis of osteocytes in adjacent to the site of implantation maternal bone. The site of defect was filled with lamellar bone tissue high in osteoblasts, osteocytes and with integrated into its structure remains of “Calc-i-oss®”. On the surface and inside the implant there were found osteogenic cells and bone foci. It was established that the osteoplastic material throughout the observation period is subjected to development and replacement by bone tissue of the regenerate, the ratio of which on the 60th day of the experiment was 25.72 ± 2.06% to 74.28 ± 2.06%, and on the 120th day - 18.31 ± 1.54% to 81.69 ± 1.54%. Conclusion: Osteoplastic material “Calc-i-oss®” exhibits biocompatibility, osteoconductive properties, ability to resorption and is replaced by bone tissue, with which it integrates well.

Critical Long Bone Defect Treated by Magnetic Scaffolds and Fixed by Permanent Magnets

2013 ◽  
Author(s):  
Alessandro Russo ◽  
Silvia Panseri ◽  
Tatiana Shelyakova ◽  
Monica Sandri ◽  
Chiara Dionigi ◽  
...  
Keyword(s):  
Finite Element ◽  
Magnetic Nanoparticles ◽  
Bone Tissue ◽  
Bone Defect ◽  
Long Bone ◽  
Bone Scaffold ◽  
Finite Element Software ◽  
Magnetic Forces ◽  
Long Bone Defect

Diaphyseal bone defect represents a significant problem for orthopaedic surgeons and patients. In order to improve and fasten bone regenerating process we implanted HA biodegradable magnetized scaffolds in a large animal model critical bone defect. A critical long bone defect was created in 6 sheep metatarsus diaphysis; then we implanted a novel porous ceramic composite scaffold (20.0 mm in length; 6.00 mm inner diameter and 17.00 mm outer diameter), made of Hydroxyapatite that incorporates magnetite (HA/Mgn 90/10), proximally fixated by two small cylindrical permanent parylene coated NdFeB magnets (one 6.00 mm diameter magnetic rod firmly incorporated into the scaffold and one 8.00 mm diameter magnetic rods fitted into proximal medullary canal, both 10.00 mm long); to give stability to the complex bone-scaffold-bone, screws and plate was used as a bridge. Scaffolds biocompatibility was previously assessed in vitro using human osteoblast-like cells. Magnetic forces through scaffold were calculated by finite element software (COMSOL Multiphysics, AC/DC Model). One week after surgery, magnetic nanoparticles functionalized with vascular endothelial growth factor (VEGF) were injected at the mid portion of the scaffold using a cutaneous marker positioned during surgery as reference point. After sixteen weeks, sheep were sacrificed to analyze metatarsi. Macroscopical, radiological and microCT examinations were performed. Macroscopical examination shows bone tissue formation inside scaffold pores and with complete coverage of scaffolds, in particular at magnetized bone-scaffold interface. X-rays show a good integration of the scaffold with a good healing process of critical bone defect, and without scaffolds mobilization. These datas were confirmed by the microCT that shown new formation of bone inside the scaffolds, in particular at magnetized bone-scaffold interface. These preliminary results lead our research to exploiting magnetic forces to stimulate bone formation, as attested in both in vitro and in vivo models and to improve fixation at bone scaffold interface, as calculated by finite element software, and moreover to guide targeted drug delivery without functionalized magnetic nanoparticles dissemination in all body. Histological analysis will be performed to confirm and quantify bone tissue regeneration at both interfaces.

Pulmonary Crystal-Storing Histiocytoma

2005 ◽  
Vol 129 (9) ◽  
pp. 1159-1163
Author(s):  
Diana N. Ionescu ◽  
Diane M. Pierson ◽  
Gefei Qing ◽  
Maomi Li ◽  
Thomas V. Colby ◽  
...  
Keyword(s):  
Lymphoproliferative Disorder ◽  
Plasma Cells ◽  
Lung Tumor ◽  
Full Description ◽  
Electron Microscopic ◽  
Hematologic Disorder ◽  
Rare Manifestation ◽  
Microscopic Features ◽  
Plasma Cell Dyscrasias ◽  
Definition Of

Abstract We describe the case of a 50-year-old woman with a lung tumor composed of crystal-storing histiocytes. These cells and associated plasma cells failed to show clonal light chain restriction, and the patient had no associated hematologic disorder. The differential diagnosis included crystal-storing histiocytosis, characterized by accumulation of crystallized immunoglobulins, a rare manifestation of monoclonal gammopathies/plasma cell dyscrasias. Crystal-laden histiocytes have previously been described in many organs. Four reports have described crystal-storing histiocytosis in the lung, always associated with a lymphoproliferative disorder. The present patient, 1 other case from our archive, and 1 case reported in the literature, all without an association with lymphoproliferative disorder, make a full description and definition of this lesion appropriate. The morphology, immunohistochemical profile, and electron microscopic features are described herein, and the term pulmonary crystal-storing histiocytoma is proposed. A practical algorithm is presented for the assessment of solitary lung masses composed of large histiocytic cells.

Cell Wall Ultrastructure in Three Strains of a Cariogenic Streptococcus

1971 ◽  
Vol 29 ◽  
pp. 338-339
Author(s):  
M. J. Kramer ◽  
Alan L. Coykendall
Keyword(s):  
Cell Wall ◽  
Dental Caries ◽  
Streptococcus Mutans ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Genetic Heterogeneity ◽  
Morphological Characteristics ◽  
Electron Microscopic ◽  
Dna Reassociation ◽  
Wall Ultrastructure

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.

Fine Structural Classification of Chromophobe Adenomas of the Human Pituitary Gland

1975 ◽  
Vol 33 ◽  
pp. 378-379
Author(s):  
K. Kovacs ◽  
E. Horvath
Keyword(s):  
Pituitary Adenomas ◽  
Secretory Activity ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Human Pituitary ◽  
Cytoplasmic Staining ◽  
Human Pituitary Gland ◽  
Microscopic Features

Chromophobe pituitary adenomas arise from adenohypophysial cells and fail to exhibit cytoplasmic staining with conventional acid or basic dyes by light microscopy. The aim of the present work was to study the electron microscopic features of these tumors, to separate them into distinct entities and to correlate their fine structural appearances with secretory activity.Among 48 surgically removed various pituitary adenomas 30 tumors were found which, based on the tinctorial characteristics of the cytoplasm, corresponded to chromophobe adenomas. For electron microscopic investigation pieces of these tumors were fixed in 2.5 per cent glutaraldehyde in Sorensen's buffer, post fixed in 1 per cent osmium tetroxide in Millonig's buffer, dehydrated in graded ethanol and embedded in Epon 812. Ultrathin sections were stained with uranyl acetate and lead citrate.By electron microscopy it was possible to separate chromophobe adenomas into 3 distinct entities: 1) adenomas consisting of sparsely granulated growth hormone cells (7 cases).

Ultrastructural Study of Apocrine Differentiation in Human Mammary Carcinoma: Correlation of Granule Content With Sex Steroid Binding

1980 ◽  
Vol 38 ◽  
pp. 742-743
Author(s):  
S. E. Levine ◽  
A. D. Brinkhous ◽  
K. S. McCarty ◽  
J. A. Mossier ◽  
K.S. McCarty
Keyword(s):  
Ultrastructural Study ◽  
Ductal Carcinoma ◽  
Apocrine Carcinoma ◽  
Electron Microscopic ◽  
Granular Eosinophilic Cytoplasm ◽  
Eosinophilic Cytoplasm ◽  
Apocrine Differentiation ◽  
Microscopic Features ◽  
Membrane Bound ◽  
Epithelial Lesions

A variant of ductal carcinoma of the human breast which has been designated apocrine carcinoma has distinctive light and electron microscopic features. Such tumors comprise approximately 0.5% of breast carcinomas. Abundant cytoplasmic membrane bound vesicles (400-600 nm) with dense homogeneous osmophilic cores characterize these tumors. These granules are also seen in apocrine metaplastic breast epithelial lesions1 and appear to be responsible for the finely granular eosinophilic cytoplasm observed by light microscopy. A high content of intermediate affinity non-saturable 4S progesteroneestrogen binding protein (PEBP) in apocrine carcinoma has been reported.2 The present ultrastructural study evaluates the presence of apocrine granules in infiltrating ductal carcinoma (NOS) to determine if a correlation exists between apocrine granule content and the quantity of PEBP present.

scholarly journals Effect of Morphological Characteristics and Biomineralization of 3D-Printed Gelatin/Hyaluronic Acid/Hydroxyapatite Composite Scaffolds on Bone Tissue Regeneration

2021 ◽  
Vol 22 (13) ◽  
pp. 6794
Author(s):  
Jae-Woo Kim ◽  
Yoon-Soo Han ◽  
Hyun-Mee Lee ◽  
Jin-Kyung Kim ◽  
Young-Jin Kim
Keyword(s):  
Hyaluronic Acid ◽  
Bone Tissue ◽  
Double Layer ◽  
Tissue Regeneration ◽  
Great Influence ◽  
Morphological Characteristics ◽  
Bone Tissue Regeneration ◽  
Hierarchical Architecture ◽  
Uniform Structure ◽  
Composite Scaffolds

The use of porous three-dimensional (3D) composite scaffolds has attracted great attention in bone tissue engineering applications because they closely simulate the major features of the natural extracellular matrix (ECM) of bone. This study aimed to prepare biomimetic composite scaffolds via a simple 3D printing of gelatin/hyaluronic acid (HA)/hydroxyapatite (HAp) and subsequent biomineralization for improved bone tissue regeneration. The resulting scaffolds exhibited uniform structure and homogeneous pore distribution. In addition, the microstructures of the composite scaffolds showed an ECM-mimetic structure with a wrinkled internal surface and a porous hierarchical architecture. The results of bioactivity assays proved that the morphological characteristics and biomineralization of the composite scaffolds influenced cell proliferation and osteogenic differentiation. In particular, the biomineralized gelatin/HA/HAp composite scaffolds with double-layer staggered orthogonal (GEHA20-ZZS) and double-layer alternative structure (GEHA20-45S) showed higher bioactivity than other scaffolds. According to these results, biomineralization has a great influence on the biological activity of cells. Hence, the biomineralized composite scaffolds can be used as new bone scaffolds in bone regeneration.

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