scholarly journals Opening paper 2015- Some comments on Bioglass: Four Eras of Discovery and Development

2015 ◽  
Vol 1 (1) ◽  
Author(s):  
Larry L. Hench
Keyword(s):  
Clinical Application ◽  
Tissue Regeneration ◽  
First Generation ◽  
Scar Tissue ◽  
Interfacial Bonding ◽  
Bioactive Glasses ◽  
Commercial Use ◽  
First Time ◽  
Host Tissues

AbstractHistorically the function of biomaterials was to replace diseased or damaged tissues. First generation biomaterials were selected to be as bio-inert as possible and thereby minimize formation of scar tissue at the interface with host tissues. Bioactive glasseswere discovered in 1969 and provided for the first time an alternative; strong, stable interfacial bonding of an implant with host tissues. In the 1980’s it was discovered that bioactive glasses could be used in particulae form to stimulate osteogenesiswhich thereby led to the concept of regeneration of tissues. This article summarizes the four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglassr. The four eras are; A) Era of Discovery, B) Era of Clinical Application, C) Era of Tissue Regeneration, and D) Era of Innovation. Key scientific and technological questions answered for the first three eras are presented. Questions still to be answered for the fourth era are included to stimulate innovation in the field.

A Genetic Basis for Design of Biomaterials for In Situ Tissue Regeneration

2008 ◽  
Vol 377 ◽  
pp. 151-166 ◽  
Author(s):  
Larry L. Hench ◽  
Julia M. Polak
Keyword(s):  
Tissue Engineering ◽  
Tissue Regeneration ◽  
Genetic Basis ◽  
First Generation ◽  
Scar Tissue ◽  
Biologically Active ◽  
Bioactive Glasses ◽  
Osteoprogenitor Cells ◽  
New Generation

Historically the function of biomaterials has been to replace diseased, damaged and aged tissues. First generation biomaterials, including bio ceramics, were selected to be as inert as possible in order to minimize the thickness of interfacial scar tissue. Bioactive glasses provided an alternative from the 1970’s onward; second generation bioactive bonding of implants with tissues and no interfacial scar tissue. This chapter reviews the discovery that controlled release of biologically active Ca and Si ions from bioactive glasses leads to the up-regulation and activation of seven families of genes in osteoprogenitor cells that give rise to rapid bone regeneration. This finding offers the possibility of creating a new generation of gene activating bioceramics designed specially for tissue engineering and in situ regeneration of tissues.

Clinical Application of Umbilical Cord Blood-Derived Stem Cells for Tissue Regeneration

2012 ◽  
pp. 35-48
Author(s):  
Yanling Liao ◽  
Kavita Radhakrishnan ◽  
Jose M. Esquilin ◽  
Brinda Mehta ◽  
Carmella van de Ven ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cord Blood ◽  
Umbilical Cord ◽  
Clinical Application ◽  
Tissue Regeneration ◽  
Umbilical Cord Blood

scholarly journals Novel Highly Degradable Chloride Containing Bioactive Glasses

2015 ◽  
Vol 1 (1) ◽  
Author(s):  
Xiaojing Chen ◽  
Natalia Karpukhina ◽  
Delia S. Brauer ◽  
Robert G. Hill
Keyword(s):  
Chemical Analysis ◽  
Chloride Content ◽  
Tris Buffer ◽  
Silicate Glasses ◽  
Ion Release ◽  
Bioactive Glasses ◽  
Glass Density ◽  
31P Mas Nmr ◽  
First Time

AbstractAddition of CaF2 to a silicate bioactive glass favours formation of fluorapatite, which is less soluble in acidic environment than hydroxyapatite. However, excess CaF2 in the glass is problematic, owing to the formation of crystalline calcium fluoride rather than fluorapatite on immersion. In this paper we investigate chloride as an alternative to fluoride in bioactive silicate glasses and in particular their bioactivity for the first time. Meltderived bioactive glasses based on SiO2-P2O5-CaO-CaCl2 with varying CaCl2 contents were synthesised and characterised by DSC. Chemical analysis of the chloride content was performed by using an ion selective electrode. Glass density was determined using Helium Pycnometry. The glass bioactivity was investigated in Tris buffer. Ion release measurements were carried out by using ICP-OES. The chemical analysis results indicated that the majority of the chloride is retained in the Q2 type silicate glasses during synthesis. Tg and glass density reduced with increasing CaCl2 content. Apatite-like phase formation was confirmed by FITR, XRD and 31P MAS-NMR. The results of the in vitro studies demonstrated that the chloride containing bioactive glasses are highly degradable and form apatite-like phase within three hours in Tris buffer and, therefore, are certainly suitable for use in remineralising toothpastes. The dissolution rate of the glass was found to increase with CaCl2 content. Faster dissolving bioactive glasses may be attractive for more resorbable bone grafts and scaffolds.

Infection of seed of subterranean clover and allied species by species of Fusarium

1980 ◽  
Vol 31 (2) ◽  
pp. 297 ◽  
Author(s):  
AW Kellock ◽  
LL Stubbs ◽  
DG Parbery
Keyword(s):  
Root Rot ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Scar Tissue ◽  
Seed Infection ◽  
Fusarium Spp ◽  
Blotting Paper ◽  
Optical Brighteners ◽  
First Time ◽  
Healthy Seed

Fusarium avenaceurn (Corda ex Fr.) Sacc. was shown for the first time to be carried in the hilum of subterranean clover (Trifolium Subterraneum L.) seed. Scanning electron microscopy and thin-section techniques showed that the fungus occurred only as dormant mycelium in parenchyma cells of funicle scar tissue. It emerged from these tissues after a 12 h incubation at 24�C and in 48 h penetrated internal parts of the seed through the hilum fissure. After 21 days on moist blotting paper, seedlings grown from infected seed developed lesions on their roots similar to those of root-rot of subterranean clover in the field. Fusarium spp. were also detected in the hilum of seeds of white (T. repens L.) and strawberry (T. fragiferum L.) clover and barrel medic (M. truncatula L.). It was demonstrated experimentally that all parts of the burr, incl~tding the funicle, became infected with F. avenaceuni when subterranean clover plants grown from healthy seed in pasteurized soil buried their burrs in soil inoculated with the fungus. Use of optical brighteners failed to trace seed infection because the compounds, although absorbed by the pathogen in culture, were not translocated.

Hierarchically mesoporous-macroporous bioactive glasses scaffolds for bone tissue regeneration

2008 ◽  
Vol 87B (2) ◽  
pp. 374-380 ◽  
Author(s):  
Hui-suk Yun ◽  
Seung-eon Kim ◽  
Yong-taek Hyun ◽  
Su-jin Heo ◽  
Jung-wook Shin
Keyword(s):  
Bone Tissue ◽  
Tissue Regeneration ◽  
Bone Tissue Regeneration ◽  
Bioactive Glasses

scholarly journals GTR Treatment in Furcation Grade II Periodontal Defects with the Recently Reintroduced Guidor PLA Matrix Barrier: A Case Series with Chronological Step-by-Step Illustrations

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Anton Friedmann ◽  
Andreas Stavropoulos ◽  
Hakan Bilhan
Keyword(s):  
Tissue Regeneration ◽  
Complete Resolution ◽  
Tooth Loss ◽  
Case Series ◽  
Maintenance Program ◽  
Regenerative Approach ◽  
Furcation Involvement ◽  
Grade Ii ◽  
First Time ◽  
Observation Period

Molars with a furcation involvement (FI) exceeding grade 1 according to Hamp’s classification are at approximately doubled risk of tooth loss. Guided tissue regeneration (GTR) is a regenerative approach in the treatment of periodontal defects and is aimed at achieving new clinical attachment formation. The aim of this case series was to assess the efficacy of a newly reintroduced polylactic acid (PLA) matrix barrier and to evaluate the feasibility of the surgical approach. 11 patients with an average age of 58.7 years were treated with GTR using a PLA matrix barrier. Patients were instructed not to brush and chew on the treated side for 4 weeks. A gentle clinical probing was performed after 6 months for the first time after surgery. The patients were included into individual maintenance program at three months’ interval. The clinical improvement was expressed by reduced horizontal penetration of the probe accompanied by vast resolution of the vertical defect component. The change from grade II to grade I or complete resolution of the FI could be seen in 8 from 11 sites included. The newly reintroduced PLA matrix barrier showed promising results after a 12-month observation period with clinical attachment gain.

Bioactive glasses in wound healing: hope or hype?

2017 ◽  
Vol 5 (31) ◽  
pp. 6167-6174 ◽  
Author(s):  
Shiva Naseri ◽  
William C. Lepry ◽  
Showan N. Nazhat
Keyword(s):  
Wound Healing ◽  
Soft Tissue ◽  
Tissue Regeneration ◽  
Tissue Repair ◽  
Great Promise ◽  
Mineralized Tissue ◽  
Bioactive Glasses ◽  
Soft Tissue Repair ◽  
Potential Applications

Bioactive glasses have long been investigated in mineralized tissue regeneration, but recently their potential applications in soft tissue repair, and in particular wound healing, have demonstrated great promise.

scholarly journals Larval gryporhynchid tapeworms (Cestoda: Cyclophyllidea) of British freshwater fish, with a description of the pathology caused by Paradilepis scolecina

2011 ◽  
Vol 86 (1) ◽  
pp. 1-9 ◽  
Author(s):  
C.F. Williams ◽  
A.J. Reading ◽  
T. Scholz ◽  
A.P. Shinn
Keyword(s):  
Freshwater Fish ◽  
Inflammatory Responses ◽  
Pathological Changes ◽  
Tinca Tinca ◽  
Hepatic Parenchyma ◽  
England And Wales ◽  
First Time ◽  
Host Tissues ◽  
Tissue Digestion

AbstractLarvae of the cyclophyllidean tapeworms Paradilepis scolecina (Rudolphi, 1819), Neogryporhynchus cheilancristrotus (Wedl, 1855) and Valipora campylancristrota (Wedl, 1855), are described from British freshwater fish. The morphometrics of the rostellar hooks, infection characteristics and host ranges of these parasites from fisheries in England and Wales are presented. Difficulties in the detection, handling and identification of these tapeworms are highlighted, and may in part explain the paucity of records from Britain. Tissue digestion was shown to be a useful technique for the examination of these parasites, providing clear and consistent preparations of the rostellar hooks for measurement. The pathological changes caused by P. scolecina to the liver of wild tench, Tinca tinca, are detailed for the first time. Tapeworms located in the hepatic parenchyma and pancreatic tissues caused little pathological damage and invoked only mild inflammatory responses. The small size of these tapeworms and their encapsulation within host tissues appear to limit the severity of pathology, compared with parasites that insert their rostellum during attachment.

The life-cycle ofProsorhynchus crucibulum(Rudolphi, 1819) Odhner, 1905, and a comparison of its cercaria with that ofProsorhynchus squamatusOdhner, 1905

Parasitology ◽  
1973 ◽  
Vol 66 (1) ◽  
pp. 133-164 ◽  
Author(s):  
R. A. Matthews
Keyword(s):  
Egg Production ◽  
Comparative Morphology ◽  
Scophthalmus Maximus ◽  
Connective Tissues ◽  
Second Intermediate Host ◽  
And Function ◽  
First Time ◽  
Advanced Development ◽  
Conger Conger ◽  
Host Tissues

The adult ofP. crucibulumis redescribed to form a basis for comparison with the cercaria and metacercaria. Particular emphasis is given to the structure and function of the rhynchus, digestive system and reproductive system. Some features, notably prepharyngeal glands and spematophores, have not previously been recorded in this species.The sporocyst and cercaria which were found inMytilus edulisare described for the first time. Out of 6907 mussels examined from Borth Rocks, Cardigan Bay, 0·26% were infected withP. crucibulumand 0·06 % withP. squamatus. The cercaria of the latter is redescribed on a comparative basis with that ofP. crucibulum, to avoid confusion. The two cercariae are clearly distinguished by three features – flame-cell formula, shape of the excretory vesicle, and structure of the tail stem (this being bilobed inP. crucibulumand trilobed inP. squamatus). The significance of the two types of tail in securing attachment to the second intermediate host is discussed.Metacercariae ofP. crucibulumwere obtained experimentally in ‘O’ group specimens ofScophthalmus maximus. Three other species of fish, namelyLimanda limanda, Onus mustelusandGobius minutuswere also successfully infected. The metacercariae did not develop in the following fish:S. rhombus, Pleuronectes platessa, Cottus bubalisandBlennius pholis. Possible mechanisms which might account for host specificity within Pleuronectidae andScophthalmusare suggested.The development of the metacercaria in the connective tissues and musculature ofS. maximuswas followed over a period of 10 months. Within 1 month of infection the hyaline cyst of parasitic origin breaks down, enabling the parasite to feed directly on the host tissues. This feature is thought to account for the advanced development of the metacercaria, which 1 month after infection could clearly be identified with the adult on the basis of comparative morphology, and at 2 months resembles the adult in every respect except the development of the vitellaria. Egg production only occurs within the intestine ofConger conger, the definitive host.

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