Enamel matrix derivative promotes reparative processes in the dental pulp.

During odontogenesis, amelogenins from the preameloblasts are translocated to differentiating odontoblasts in the dental papilla, suggesting that amelogenins may be associated with odontoblast changes during development. In the present study, we have explored the effects of enamel matrix derivative (EMD) on the healing of a pulpal wound. Coronal pulp tissue of permanent maxillary premolars of miniature swine were exposed through buccal class V cavities.

Emdogain--periodontal regeneration based on biomimicry.

Biomimicry has been introduced as a term for innovations inspired by nature [1]. Such innovations may appear in almost every part of modern society. This review on the effects of enamel matrix proteins on the formation of cementum and the development of emdogain for regeneration of periodontal tissues lost due to periodontitis shows an example of biomimicry in dentistry.

Autocrine growth factors in human periodontal ligament cells cultured on enamel matrix derivative.

Objective: Enamel extracellular matrix proteins in the form of the enamel matrix derivative EMDOGAIN (EMD) have been successfully employed to mimic natural cementogenesis to restore fully functional periodontal ligament, cementum and alveolar bone in patients with severe periodontitis. When applied to denuded root surfaces EMD forms a matrix that locally facilitates regenerative responses in the adjacent periodontal tissues. The cellular mechanism(s), e.

Clinical safety of enamel matrix derivative (EMDOGAIN) in the treatment of periodontal defects.

The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions.

In vitro studies on periodontal ligament cells and enamel matrix derivative.

The recognition that periodontal regeneration can be achieved has resulted in increased efforts focused on understanding the mechanisms and factors required for restoring periodontal tissues so that clinical outcomes of such therapies are more predictable than those currently being used. In vitro models provide an excellent procedure for providing clues as to the mechanisms that may be required for regeneration of tissues. The investigations here were targeted at determining the ability of enamel matrix derivative (EMD) to influence specific properties of periodontal ligament cells in vitro.

Formulation of enamel matrix derivative for surface coating. Kinetics and cell colonization.

Enamel Matrix Derivative (EMD) contains a protein complex belonging to the amelogenin family. Enamel matrix as well as EMD have been found to promote periodontal regeneration when applied onto denuded root surfaces in dehiscence models. In the present studies it is shown that propylene glycol alginate (PGA) is a suitable vehicle for EMD for its local application.

Periodontal regeneration in a buccal dehiscence model in monkeys after application of enamel matrix proteins.

There is increasing evidence that cells of the epithelial root sheath synthesize enamel matrix proteins and that these proteins play a fundamental role in the formation of acellular cementum, the key tissue in the development of a functional periodontium. The purpose of the present study was to explore the effect of locally applied enamel matrix and different protein fractions of the matrix on periodontal regeneration in a buccal dehiscence model in monkeys. Buccal, mucoperiosteal flaps were raised from the canine to the 1st molar on each side of the maxilla.

Integrated myogenic and metabolic control of vascular tone in skeletal muscle during autoregulation of blood flow.

The hypothesis that autoregulation of blood flow in cat skeletal muscle is due to metabolic factors related to blood flow that interact with force-sensitive myogenic mechanisms is tested by means of a mathematical model. The vascular bed is assumed to consist of the reactive series-coupled proximal arterial and microvascular sections and the passive large vein section. Myogenic mechanisms are described by a slowly adapting force-receptor that determines the activation level of smooth muscle.

Analysis of gated membrane currents and mechanisms of firing control in the rapidly adapting lobster stretch receptor neurone.

1. The gated membrane currents (a tetrodotoxin-sensitive Na+ current and a tetraethylammonium- and 4-aminopyridine-sensitive K+ current) of the rapidly adapting stretch receptor neurone of lobster were investigated with respect to their kinetic properties using electrophysiological, pharmacological, and mathematical techniques. 2.

Current activation by membrane hyperpolarization in the slowly adapting lobster stretch receptor neurone.

1. A polarization-induced membrane current, IQ, was investigated in the slowly adapting lobster stretch receptor neurone using conventional electrophysiological techniques including intracellular ion measurements. 2.

Transmembrane ion balance in slowly and rapidly adapting lobster stretch receptor neurones.

The transmembrane exchange of Na+, K+, and Cl- in slowly and rapidly adapting lobster stretch receptor neurones was studied using ion-sensitive microelectrodes in combination with conventional electrophysiological techniques. The investigation was founded on the assumption that the transmembrane ion exchange is accomplished by active and passive transports which add up to zero in steady state for each ion involved. The active transports are assumed to include Na+ and K+ transports driven by an electrogenic Na-K pump.

A dynamic model of smooth muscle contraction.

A dynamic model of smooth muscle contraction is presented and is compared with the mechanical properties of vascular smooth muscle in the rat portal vein. The model is based on the sliding filament theory and the assumption that force is produced by cross-bridges extending from the myosin to the actin filaments. Thus, the fundamental aspects of the model are also potentially applicable to skeletal muscle.

Impulse firing in the slowly adapting stretch receptor neurone of lobster and its numerical simulation.

A mathematical model of the electrical activity of the slowly adapting lobster stretch receptor neurone is presented. The model is based on constant field and state transition theory and employs measurements of the kinetics of membrane currents in sub- and near-threshold voltage regions (Gestrelius, Grammp & Sjölin 1981, Gestrelius & Grampp 1983, Gestrelius, Grampp & Sjölin 1983, Edman, Gestrelius & Grampp 1983). In addition to the classical action potential generating mechanisms (Hodgkin & Huxley 1952) the model also includes the processes of slow Na and K inactivation, ion flux dependent changes of the intracellular Na+ and K+ concentrations, and the activity of an electrogenic Na-K pump sensitive to intracellular Na+ accumulation.

Intracellular ion control in lobster stretch receptor neurone.

The control of intracellular ion concentrations by means of passive and active transmembrane ion transports was investigated in the lobster stretch neurone using electrophysiological and pharmacological techniques in combination with recording with ion-sensitive microelectrodes. In resting conditions [Na+]i, [K+]i, and [Cl-]i were, in both slowly and rapidly adapting cells, found to be in the order of 20, 155, and 50 mM, respectively. In the slowly adapting cell impulse firing at stationary frequencies of 7-10 Hz caused an increase in [Na+]i and a decrease in [K+]i of 20-30 mM; [Cl-]i was only little affected, the rise in [Na+]i led to an enhanced Na-K pump activity noticeable as an increase in pump current production.

Kinetics of the TTX sensitive Na+ current in the slowly adapting lobster stretch receptor neurone.

The kinetics of the TTX sensitive Na+ current (INa) in the slowly adapting lobster stretch receptor neurone were investigated in sub- and near-threshold voltage regions using electrophysiological and pharmacological techniques. In dynamic conditions INa was found to display both fast and slow reactions. These were attributed to a fast Hodgkin-Huxley type of Na activation and inactivation, and a slow type of Na inactivation, respectively.

Kinetics of the TEA and 4-AP sensitive K+ current in the slowly adapting lobster stretch receptor neurone.

The kinetics of the TEA and 4-AP sensitive K+ current (IK) in the slowly adapting lobster stretch receptor neurone were investigated in sub- and near-threshold voltage regions using electrophysiological and pharmacological techniques. In dynamic conditions IK was found to display both fast and slow reactions. These were attributed to a Hodgkin-Huxley type of K activation, and a slow type of K inactivation, respectively.

Subthreshold and near-threshold membrane currents in lobster stretch receptor neurones.

1. The ion currents in the slowly and rapidly adapting stretch receptor neurone of lobster were investigated with respect to their nature and stationary kinetics in sub- and near-threshold voltage regions using electrophysiological and pharmacological techniques. 2.

Continuous regeneration of NAD(P)+ by flavins covalently bound to sepharose.

Various flavins, FMN, FAD, and acriflavin, were immobilized to Sepharose using several different coupling methods. The only product stable enough to permit extended studies was acriflavin coupled to epoxy-substituted Sepharose. The nonenzymic oxidizing capacity towards NAD(P) H was investigated and a 25% specific activity, compared to that of free acriflavin, was observed.

Preparation of an alcohol-dehydrogenase--NAD(H)--sepharose complex showing no requirement of soluble coenzyme for its activity.

1. Horse liver alcohol dehydrogenase and an NADH analogue, N6-[(6-aminohexyl)carbamoylmethyl]-NADH, have been co-immobilized to Sepharose 4B under conditions permitting binary complex formation between the enzyme and the cofactor. 2.