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

Abstract 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. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®.     

Effects of (R)-8-OH-DPAT and the enantiomers of UH-301 on motor activities in the rat: antagonism of (R)-8-OH-DPAT-induced effects.

The effects of the enantiomers of 5-fluoro-8-hydroxy-2-(dipropylamino)tetralin, UH-301 and the potent 5-HT1A-receptor agonist (R)-8-hydroxy-2-(dipropylamino)tetralin, (R)-8-OH-DPAT, on locomotion, rearing and total activity were studied in rats. The experiments were performed as tests either of exploratory activity in non-habituated rats or of motor activity of rats habituated to the environment for 2 h before drug injection. (R)-8-OH-DPAT increased locomotion and total activity and decreased rearing in both conditions. (R)-UH-301 increased locomotion and slightly also total activity in habituated rats and decreased rearing in both conditions. (S)-UH-301 decreased locomotion and rearing in both conditions but only in doses of 10 mumol/kg and above. Lower doses of (S)-UH-301 (10 mumol/kg) antagonized (R)-8-OH-DPAT-induced increases of locomotion and total activity. As (S)-UH-301 decreased rearing, per se, it was not able to antagonize the (R)-8-OH-DPAT induced decrease. These results further support previous data that (S)-UH-301 is a 5-HT1A antagonist while (R)-UH-301 is a 5-HT1A agonist.     

Red blood cells stimulate fibroblast-mediated contraction of three dimensional collagen gels in co-culture

OBJECTIVE AND DESIGN: Following injury, red blood cells (RBC) may interact with extracellular matrix (ECM). In the present study we hypothesised that RBC, and soluble factors from RBC, might mediate remodelling of ECM by affecting fibroblast-mediated contraction of three dimensional collagen gels. MATERIALS AND METHODS: Human lung fibroblasts (HFL-1), were cultured together with isolated RBC, conditioned medium from RBC (RBC-CM) and hemolysed RBC in type I collagen gels. Gel contraction was determined by an image analyser. RESULTS: Both RBC, RBC-CM and hemolysed RBC stimulated gel contraction by fibroblasts (P < 0.001), compared to fibroblasts alone. The RBC-CM stimulated (P < 0.01) gel contraction in a time and concentration dependent manner. A similar effect was observed when supernatant from hemolysed RBC was tested. The production of fibronectin was increased (P < 0.01) in the co-culture system, compared to fibroblasts cultured alone. CONCLUSIONS: The present study shows that RBC can interact with mesenchymal cells in vitro. The ability of RBC to modulate fibroblast-mediated contraction in vitro, might therefore be an important mechanism regulating repair processes after injury.     

Emergency reversal of anticoagulation after intracerebral hemorrhage.

BACKGROUND AND PURPOSE: Although intracerebral hemorrhage is one of the most serious complications during oral anticoagulant therapy, there are no guidelines on emergency treatment with respect to reversal of anticoagulation effect in these patients. METHODS: We retrospectively compared laboratory data and clinical features in 17 cases of anticoagulant-related intracerebral hemorrhage treated with prothrombin complex concentrate (n = 10) or fresh-frozen plasma (n = 7). RESULTS: In the group of patients treated with prothrombin complex concentrate, the mean prothrombin time decreased from 2.83 to 1.22 International Normalized Ratio within 4.8 hours, compared with a decrease from 2.97 to 1.74 within 7.3 hours in those given fresh-frozen plasma (i.e., four to five times more rapidly after treatment with prothrombin complex concentrate) (p less than 0.001). Symptoms and signs of intracerebral hemorrhage, measured on an eight-graded Reaction Level Scale, progressed on average 0.2 grades in patients given prothrombin complex concentrate compared with 1.9 grades in those given fresh-frozen plasma (p less than 0.05). In patients with prothrombin values above 1.46, clinical progression within 12 hours occurred in five of six cases. CONCLUSIONS: Treatment with prothrombin complex concentrate reverses anticoagulation more rapidly than fresh-frozen plasma, which might be of importance for the prevention of further bleeding.     

Neonatal Exposure to a Combination of N-Methyl-d-aspartate and γ-Aminobutyric Acid Type A Receptor Anesthetic Agents Potentiates Apoptotic Neurodegeneration and Persistent Behavioral Deficits

Background: During the brain growth spurt, the brain develops and modifies rapidly. In rodents this period is neonatal, spanning the first weeks of life, whereas in humans it begins during the third trimester and continues 2 yr. This study examined whether different anesthetic agents, alone and in combination, administered to neonate mice, can trigger apoptosis and whether behavioral deficits occur later in adulthood.

Methods: Ten-day-old mice were injected subcutaneously with ketamine (25 mg/kg), thiopental (5 mg/kg or 25 mg/kg), propofol (10 mg/kg or 60 mg/kg), a combination of ketamine (25 mg/kg) and thiopental (5 mg/kg), a combination of ketamine (25 mg/kg) and propofol (10 mg/kg), or control (saline). Fluoro-Jade staining revealed neurodegeneration 24 h after treatment. The behavioral tests-spontaneous behavior, radial arm maze, and elevated plus maze (before and after anxiolytic)-were conducted on mice aged 55-70 days.

Results: Coadministration of ketamine plus propofol or ketamine plus thiopental or a high dose of propofol alone significantly triggered apoptosis. Mice exposed to a combination of anesthetic agents or ketamine alone displayed disrupted spontaneous activity and learning. The anxiolytic action of diazepam was less effective when given to adult mice that were neonatally exposed to propofol.     

3-Hydroxyanthranilic acid accumulation following administration of the 3-hydroxyanthranilic acid 3,4-dioxygenase inhibitor NCR-631

In the kynurenine pathway of tryptophan metabolism, 3-hydroxyanthranilic acid is the substrate for formation of the excitotoxin quinolinic acid by 3-hydroxyanthranilic acid 3, 4-dioxygenase. This study was designed to characterize the effects on 3-hydroxyanthranilic acid after treatment with the 3-hydroxyanthranilic acid 3,4-dioxygenase inhibitor 4, 6-di-bromo-3-hydroxyanthranilic acid (NCR-631) in Sprague-Dawley rats. The blood plasma and brain concentrations of 3-hydroxyanthranilic acid were found to increase rapidly in a dose-dependent manner after gavage administration of NCR-631. However, the effect was relatively transient, with a decline in 3-hydroxyanthranilic acid levels already at 1h after NCR-631 treatment. Similar increases in plasma levels of 3-hydroxyanthranilic acid were observed following either gavage or parenteral (i.v. or s.c.) administration of NCR-631 (25 mg/kg). Only a minor enhancement of the NCR-631-induced increase in plasma 3-hydroxyanthranilic acid levels was found after sub-chronic treatment (25 mg/kg by gavage; 7 days, b.i.d.), suggesting a low propensity for altered 3-hydroxyanthranilic acid 3,4-dioxygenase activity following repeated inhibition. Administration of [14C]NCR-631 suggested 20 min initial plasma half life and an oral absorption around 50%. A dose of 250 mg/kg [14C]NCR-631 given by gavage provided plasma levels of almost 2 micromol/ml and a brain concentration of approximately 16 nmol/g, when analyzed 15 min after administration. Neither acute nor sub-chronic administration of NCR-631 caused any substantial effects on quinolinic acid levels in plasma or brain. Also, the plasma levels of kynurenic acid, another neuroactive kynurenine pathway metabolite, were unaffected by acute NCR-631 treatment. Moreover, the brain levels of the major cerebral tryptophan metabolites 5-hydroxytryptamine and 5-hydroxyindoleacetic acid remained unchanged following administration of NCR-631. Although reversible inhibition of 3-hydroxyanthranilic acid 3, 4-dioxygenase with NCR-631 in normal rats is insufficient to cause substantial changes in the levels of quinolinic acid or other important tryptophan metabolites, it causes a major accumulation of the substrate 3-hydroxyanthranilic acid.     

Developmental neurotoxicity of four ortho-substituted polychlorinated biphenyls in the neonatal mouse

The objective of the present study was to investigate whether neonatal exposure to single PCB (polychlorinated biphenyl) congeners 2,4,4'-trichlorobiphenyl (IUPAC 28), 2,2',5,5'-tetrachlorobiphenyl (IUPAC 52), 2,3',4,4',5-pentachlorobiphenyl (IUPAC 118) and 2,3,3',4,4',5-hexachlorobiphenyl (IUPAC 156) when given as one single dose (0.7-14 μmol/kg body weight per os) to 10-day-old male NMRI mice could induce persistent neurotoxic effects in the adult animal. Furthermore, to ascertain whether behavioural aberrations, both in spontaneous behaviour and in learning and memory function, were followed by changes in the cholinergic and/or the dopaminergic system. It was found that neonatal exposure to lightly chlorinated ortho-substituted PCBs, 2,4,4'-tri- and 2,2',5,5'-tetrachlorobiphenyls, can induce persistent aberrations in spontaneous behaviour. Neonatal exposure to 2,2',5,5'-tetrachlorobiphenyl also affected learning and memory functions in the adult animal. In the animals showing a deficit in memory and learning function, the cholinergic nicotinic receptors in the cerebral cortex were affected. Exposure to 2,3',4,4',5-penta- and 2,3,3',4,4',5-hexachlorobiphenyl, mono-ortho congeners ('co-planar-like'), in the same dose range did not cause any significant change in the investigated behavioural variables, spontaneous and swim-maze behaviour.     

Alpha-phenyl-tert-butyl-nitrone (PBN) reverses age-related maze learning performance and motor activity deficits in C57 BL/6 mice

Two experiments were performed to study the effects of age and repeated administration of alpha-phenyl-tert-butyl-nitrone (PBN), the free radical spin-trapping agent, upon spontaneous motor activity levels and radial arm maze performance in normal young (3 month old) and normal aged (15 month old) C57 BI/6 mice. In Experiment 1, the aged mice were found to show reduced locomotor and rearing behaviour in comparison with the young mice. In the radial eight-arm maze learning task, the aged mice performed at a comparable level to the young mice during the first learning trial (Day 1) but made significantly more errors and showed longer total latencies during the second trial presented 24h later. In Experiment 2, the aged and young mice were subchronically administered either PBN at a dose of 50mg/kg, s.c. over 12 days, or saline. Spontaneous motor activity was tested 72h after the last injection. 36h later the first test trial in the radial arm maze was presented; this was followed after a further 24h by the second test trial. Subchronic treatment with PBN increased locomotion counts in the aged (15 month old) mice during the 60min test period, but decreased rearing during the first 30min of the test period. In the radial arm maze, the performance deficit shown during the second test trial by the aged mice was abolished by repeated PBN administration; both the number of errors and the latencies to all eight pellets were significantly reduced in the aged mice that received PBN. PBN did not exert any effects upon the performance of the young mice. These results, considered in conjunction with other studies using gerbils or rats, implicate the involvement of free radical species in the deterioration of function in the aged C57 BI/6 mouse.     

Assessing hematopoietic chimerism after allogeneic stem cell transplantation by multiplexed SNP genotyping using microarrays and quantitative analysis of SNP alleles.

Single-nucleotide polymorphisms (SNPs) have the potential to be particularly useful as markers for monitoring of chimerism after stem cell transplantation (SCT) because they can be analyzed by accurate and robust methods. We used a two-phased minisequencing strategy for monitoring chimerism after SCT. First, informative SNPs with alleles differing between donor and recipient were identified using a multiplex microarray-based minisequencing system screening 51 SNPs to ensure that multiple informative SNPs were detected in each donor-recipient pair. Secondly, the development of chimerism was followed up after SCT by sensitive, quantitative analysis of individual informative SNPs by applying the minisequencing method in a microtiter plate format. Using this panel of SNPs, we identified multiple informative SNPs in nine unrelated and in 16 related donor-recipient pairs. Samples from nine of the donor-recipient pairs taken at time points ranging from 1 month to 8 years after transplantation were available for analysis. In these samples, we monitored the allelic ratios of two or three informative SNPs in individual minisequencing reactions. The results agreed well with the data obtained by microsatellite analysis. Thus, we conclude that the two-phased minisequencing strategy is a useful approach in the following up of patients after SCT.     

Increased susceptibility to adult paraoxon exposure in mice neonatally exposed to nicotine.

Low-dose exposure of neonatal mice to nicotine has earlier been shown to induce an altered behavioral response to nicotine in adulthood. Organophosphorus insecticides are known to affect the cholinergic system by inhibition of acetylcholinesterase. This study was undertaken to investigate whether neonatal exposure to nicotine makes mice more susceptible to a known cholinergic agent. Neonatal, 10-day-old, male mice were exposed to nicotine-base (33 microg/kg body weight) or saline s.c. twice daily on five consecutive days. At 5 months of age the animals were exposed to paraoxon (0.17 or 0.25 mg/kg body weight [29% and 37% inhibition of cholinesterase, respectively]) or saline sc every second day for 7 days. Before the first paraoxon injection, the animals were observed for spontaneous motor behavior. The spontaneous motor behavior test did not reveal any differences in behavior between the treatment groups. Immediately after the spontaneous behavior test, the animals received the first injection of paraoxon and were observed for acute effects of paraoxon on spontaneous motor behavior. The acute response to paraoxon in the spontaneous motor behavior test was a decreased level of activity in mice neonatally exposed to nicotine. Control animals showed no change in activity. Two months after the paraoxon treatment, the animals were again tested for spontaneous motor behavior. Animals neonatally exposed to nicotine and exposed to paraoxon as adults showed a deranged spontaneous motor behavior, including hyperactivity and lack of habituation.