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Treatment of avulsed young permanent teeth aims to revascularize the dental pulp. The study of therapeutic strategies for avulsed teeth has been hindered by the scarcity of experimental models. The purpose of this work is to characterize two model systems to study dental pulp revascularization. Tooth slices from human third molars were prepared with a sterile diamond saw. The tooth slices were cultured in vitro for up to 7 days. Immunohistochemical staining with Factor VIII showed an increase in microvascular density in pulps treated with 50 ng/mL rhVEGF(165) as compared with untreated controls (p < 0.05). Alternatively, tooth slices were prepared and immediately implanted subcutaneously in immunodeficient mice. Pulp vitality and vascularization were confirmed by histological analysis and terminal deoxynucleotide transferase dUTP nick end labeling assays 7 days after implantation. The models presented here may be valuable in the assessment of angiogenesis-based therapeutic strategies for the dental pulp.

Human immunodeficiency virus type 1 resistance to nucleoside reverse transcriptase inhibitors such as 3'-azido-2', 3'-dideoxythymidine (AZT) can arise through mutations in the coding region of reverse transcriptase (RT) that enhance the enzyme's ability to remove the drug after it has been incorporated. This excision activity of HIV-1 RT has been well characterized in a number of in vitro systems. However, the in vitro findings do not provide a complete picture of the in vivo significance of this resistance mechanism. This review will attempt to bridge the gap between the in vitro observations and the in vivo environment by summarizing the fragmentary information that is available about the intracellular conditions that may influence drug excision in cell subpopulations that are infected by HIV-1. Topics that will be discussed include (a) intracellular compounds HIV-1 RT may use to remove chain terminators; (b) how dNTPs can affect excision activity and how these effects differ in different immune cell subpopulations; (c) the influence of HIV infection on excision activity - e.g., through immune activation of infected cells or through changes indirectly induced in cells that subsequently become infected; (d) intracellular conditions that favor selection for mutations that increase the excision-based resistance mechanism; (e) the importance of macrophages in the selection of resistance mutations. Understanding factors that control excision in the intracellular environment will greatly enhance our understanding of the process of selection for this class of drug resistance mutations and may open doors for the development of novel targets for antiviral therapy.

Background information. Substantial evidence indicates the existence of NCSCs (neural crest-derived stem cells) in embryonic mandibular processes; however, they have not been fully investigated or isolated. The aim of the present study was to isolate stem cells from mandibular process during embryonic development by MACS (magnetic-activated cell sorting). The findings show that the cells are multipotent and self-renewing. Results. LNGFR (low-affinity nerve-growth-factor receptor)+ cells were isolated from rat embryonic mandibular processes by MACS. The cells were grown in clonal culture by limiting dilution to assess their developmental potential. Clone analysis indicated that, first, LNGFR+ cells are multipotent, being able to generate at least neurons and Schwann cells, similar to peripheral neural crest stem cells. Secondly, multipotent LNGFR+ cells generate multipotent progenies, indicating that they are capable of self-renewal and therefore are stem cells. Thirdly, manipulation of the medium supplementation alters the fate of the isolated LNGFR+ cells. Conclusions. These results indicate that LNGFR antibodies label NCSCs with high specificity and purity, and suggest that positive selection using these antibodies may become the method of choice for obtaining multipotent cells from rat embryonic mandibular processes for tissue engineering or regenerative therapeutic use.

Aims To develop and evaluate for the National Prescribing Service (NPS) a web-based interactive prescribing curriculum for Australian senior medical students based on the World Health Organization’s Guide to Good Prescribing. Methods Teachers of prescribing from all Australian medical schools in 2000 wrote 12 case-based modules which were converted to on-line format. Objective evidence was provided for selecting first-line medicines from available alternatives by comparing efficacy, safety, convenience and cost. The curriculum was made available to final year students in 2001 and was evaluated by measuring use from web statistics and by semistructured interviews with 15 teachers (2003) and on-line surveys of 363 students over 2003 and 2004. Results By 2004 the curriculum was used by nine of 11 possible medical schools. Uptake increased each year from 2001 and all 12 modules were accessed consistently. Student access was significantly (P

In this study, the progenitor cells isolated from the human dental pulp were used to study the effects of ethylenediaminetetraacetic acid-soluble dentin extract (DE) on their differentiation and mineralization to better understand tissue injury and repair in the tooth. Mineralization of the matrix was increasingly evident at 14, 21, and 28 d after treatment with a mineralization supplement (MS) (ascorbic acid [AA], beta-glycerophosphate [beta-GP]) and MS + DE. Real-time polymerase chain reaction results showed type I collagen upregulation after the addition of MS + DE at 7 d. Alkaline phosphatase was downregulated after the mineralization became obvious at 14 d. Bone sialoprotein was shown to be upregulated in the mineralized cell groups at all time points and dentin sialophosphoprotein after 7 d. Core binding factor a 1 was upregulated by the treatment of MS and DE at 7, 14, and 21 d. These results indicated that the MS of AA, beta-GP, and DE synergistically induced cell differentiation of pulp progenitor cells into odontoblast-like cells and induced in vitro mineralization.

BACKGROUND AND AIM The relative roles of self and ambulatory blood pressure monitoring (self BPM, ABPM, respectively) have yet to be clearly defined despite accumulating evidence of self BPM benefits, particularly in hypertension management. In particular, measurements comparable to ABPM have been documented with self-measurement, usually twice daily over one or more days. Nevertheless, ABPM offers a series of recordings performed throughout the day that can be invaluable during drug treatment. Consequently, this study evaluated 18 normotensive and 79 hypertensive patients, including 21 not taking hypotensive agents, and measured their blood pressure at least every 2 h while they were also undergoing ABPM. METHODS AND RESULTS Self-measurement was performed between five and 12 times during the day with 77% of subjects preferring self BPM rather than daytime ABPM. When compared with the closest ABP measurement, mean systolic and diastolic pressures were not significantly different throughout the day in both normotensive and hypertensive patients. However, a comparison of a series of ABPM hourly averages (three readings performed closest to the respective self BPM reading) throughout the day in all hypertensive subjects found ABPM readings to be slightly but significantly lower (3.3 systolic, 2.2 mmHg diastolic; P < 0.05). CONCLUSION It is concluded that multiple self-measurements throughout the day provides comparable information to daytime ABPM, is preferred by most patients, and should be a cost-effective alternative in the diagnosis and management of hypertension.

Human immunodeficiency virus type 1 (HIV-1) replication is inhibited by the incorporation of chain-terminating nucleotide analogs at the 3′ end of the nascent DNA chain during reverse transcription. Viral replication in the presence of these drugs results in selection of resistance mutations in the viral sequences encoding reverse transcriptase (RT), the replicative enzyme for HIV. Mutations at six codons in RT (M41L, D67N, K70R, L210W, T215Y or -F, and K219Q) are commonly selected by the nucleoside inhibitor 3′-azido-3′-deoxythymidine (AZT) and have been shown to confer AZT resistance through an increased ability to remove the chain terminator after it has been incorporated into DNA (1, 29, 46). These mutations are also correlated with significant resistance to other chain-terminating nucleosides (33, 34, 47). Excision has been shown to occur by RT-catalyzed transfer of the chain-terminating residue to a variety of acceptor substrates in vitro by a reaction that is related to pyrophosphorolysis (1, 5, 16, 29, 31, 42, 43). The intracellular acceptor for this reaction is unknown, but likely candidates include nucleoside triphosphates and nucleoside diphosphates as well as inorganic pyrophosphate (PPi). In this report, we show that cell extracts contain a mixture of acceptor substrates for the excision reaction. ATP or PPi predominates depending on the cell type and its activation status. For these experiments, it was necessary to avoid errors in the measurement of PPi levels in the extracts, which can be affected by a number of factors: the breakdown of unstable intracellular compounds to form PPi during the extraction procedure, contaminating platelets, and cellular enzymes that alter PPi levels during the extraction process. Results obtained with an optimized extraction procedure disagree with widely quoted values of 130 to 150 μM for intracellular PPi concentration in unstimulated lymphocytes (3); our results are more in agreement with the data of De La Rosa et al. (8) that PPi concentrations are less than 10 μM. We also show that PPi concentrations increased to 55 to 79 μM in highly stimulated T cells. At this level of PPi, pyrophosphorolysis predominated and the overall rate of excision was similar for wild-type (WT) and AZT-resistant enzymes. To explain selection of AZT resistance mutations in vivo, it is possible that PPi-dependent excision is enhanced in the mutant virus but not detected in the in vitro assays. Alternatively, selection may occur in an intracellular environment that favors ATP-dependent excision over pyrophosphorolysis. Preliminary reports of this work have been presented previously (A. J. Smith, P. R. Meyer, D. Asthana, M. R. Ashman, and W. A. Scott, Abstr. XII Int. HIV Drug Resist. Workshop, abstr. 38, 2003; A. J. Smith, P. R. Meyer, and W. A. Scott, Abstr. XIII Int. HIV Drug Resist. Workshop, abstr. 25, 2004).

Summary Objective: The function of apoptosis and its regulation in odontoblasts remain unclear. In this study, we characterize the possible role of transforming growth factor (TGF)-β 1 in the induction of apoptosis and the molecular mechanisms that mediate TGF-β1-induced apoptosis in odontoblasts. Methods: Annexin V/propidium iodide staining, cell Death Detection ELISA and DNA ladder were used to examine the effect of TGF-β1 on apoptosis in a mouse odontoblast-like cell line, MDPC-23. Stable cell clones expressing Smad2 or Smad3 dominant negative mutants, or wild-type Smad7 were constructed to investigate the role of Smad proteins in the mediation of apoptosis by TGF-β1 in MDPC-23 cells. The TGF-β1-induced transcriptional activity in stable cell clones expressing Smad proteins was analyzed by a transient transfected TGF-β-responsive reporter gene, p3TP-Lux. Results: TGF-β1 can induce apoptotic cell death in MDPC-23 cells in a dose-dependent manner. Transfection of dominant negative mutant forms of Smad2 or Smad3 blocked TGF-β1-induced apoptosis; moreover, the Smad3 mutant was more efficient than the Smad2 mutant. Transfection of Smad7, an inhibitory Smad, also significantly inhibited TGF-β1-induced apoptosis of these cells. Over-expression of Smad3 dominant negative mutant or Smad7 significantly inhibited TGF-β1-induced transcriptional activity. Conclusion: These results suggest that Smad proteins are involved in TGF-β1-induced apoptosis of odontoblast cells.

Cranial neural crest-derived ectomesenchymal cells represent a population of pluripotent stem cells giving rise to many of the various oro-facial and dental tissues. The factors determining the terminal fate of these cells are still unclear. The potentiality of human embryonic ectomesenchymal cells from the first branchial arch have been investigated when isolated and grown in a three-dimensional (3D)-collagen gel culture system in the presence of dentin matrix-derived non-collagenous proteins (DNCP) and TGFbeta-1. Functional differentiation of cells showing some characteristics of odontoblast-like cells could be observed when the cells were cultured with DNCP+TGFbeta-1 or DNCP, however, only cytological differentiation was observed during culture with TGFbeta-1 alone. The characteristics of these cells was assessed by morphological appearance, expression of the odontoblast phenotype marker dentin sialophosphoprotein (DSPP), increased alkaline phosphatase levels and formation of mineralised nodules in vitro. The results indicate that these embryonic cells from the first branchial arch are capable of responding to the inductive stimulus of DNCP or DNCP+TGFbeta-1 when isolated and grown in the 3D collagen gel culture system. The capacity of the isolated cells to differentiate into mineralizing cells showing some characteristics of odontoblast-like cells under these growth conditions highlights the potential of such approaches for tissue engineering strategies for hard-tissue regeneration after injury.

High-throughput characterisation of the molecular response of pulpal tissue under carious lesions may contribute to improved future diagnosis and treatment. To identify genes associated with this process, oligonucleotide microarrays containing approximately 15,000 human sequences were screened using pooled total RNA isolated from pulpal tissue from both healthy and carious teeth. Data analysis identified 445 genes with 2-fold or greater difference in expression level, with 85 more abundant in health and 360 more abundant in disease. Subsequent gene ontological grouping identified a variety of processes and functions potentially activated or down-modulated during caries. Validation of microarray results was obtained by a combination of real-time and semi-quantitative PCR for selected genes, confirming down-regulation of Dentin Matrix Protein-1 (DMP-1), SLIT 2, Period-2 (PER 2), Period-3 (PER 3), osteoadherin, Glypican-3, Midkine, activin receptor interacting protein-1 (AIP 1), osteoadherin and growth hormone receptor (GHR), and up-regulation of Adrenomedullin (ADM), Interleukin-11 (IL-11), Bone sialoprotein (BSP), matrix Gla protein (MGP), endothelial cell growth factor-1 (ECGF 1), inhibin beta A and orosomucoid-1 (ORM 1), in diseased pulp. Real-time PCR analyses of ADM and DMP-1 in a panel of healthy and carious pulpal tissue and also in immune system cells highlighted the heterogeneity of caries and indicated increased expression of ADM in neutrophils activated by bacterial products. In contrast, DMP-1 was predominantly expressed by cells native to healthy pulpal tissue. This study has greatly extended our molecular knowledge of dental tissue disease and identified involvement of genes previously unassociated with this process.

The presence, in patients with primary and secondary Sjogren's syndrome (SS), of autoantibodies that acutely inhibit M(3) muscarinic receptor (M3R)-mediated bladder contractions is difficult to reconcile with the fact that symptoms of detrusor overactivity and other features of cholinergic hyperresponsiveness occur in this disease. This study was undertaken to examine the in vivo effects of these autoantibodies on bladder function by examining bladder responsiveness and compliance following passive transfer of patient IgG to mice.Contractile responses of isolated bladder strips both to the muscarinic agonist carbachol and to electrically evoked acetylcholine release were measured 48 hours after injection of mice with patient or control IgG. A whole bladder assay with intact neuronal pathways was developed to assess bladder wall compliance on filling cystometry. Expression of M3R in bladders from IgG-injected mice was assessed by immunohistochemistry.Passive transfer of SS IgG with inhibitory anti-M3R activity produced a paradoxical increase in contractile responses of detrusor strips to cholinergic stimulation. Cystometry of whole bladders revealed a corresponding decrease in bladder wall compliance and phasic detrusor contractions upon filling, replicating the urodynamic features of an overactive bladder. The features of cholinergic hyperresponsiveness were associated with increased postsynaptic M3R expression and were reproduced by injecting mice with a rabbit antibody against the second extracellular loop of M3R.These findings are consistent with the notion that there is initial inhibition of parasympathetic neurotransmission by antagonistic autoantibodies to M3R, which produces a compensatory increase in M3R expression in vivo. The enhanced cholinergic responses during bladder distention result in detrusor overactivity. We conclude that the overactive bladder associated with SS is an autoantibody-mediated disorder of the autonomic nervous system, which may be part of a wider spectrum of cholinergic hyperresponsiveness.

[1] Density-dependent circulation of seawater in coastal aquifers results in submarine groundwater discharge (SGD) across the seabed that is a mixture of terrestrial groundwater and former marine water. In this study, the controls of the relative amount of seawater to freshwater in SGD were investigated numerically using the FEFLOW and SUTRA codes. It was found that the key controls could be expressed in the form of a single nondimensional recirculation number that incorporates the combined effects of free convection, forced convection, and hydrodynamic dispersion on convective overturn within the coastal salt wedge. Anisotropy effects were incorporated into the recirculation number with limited success based on the principle of equivalent isotropic hydraulic conductivity. The type of boundary condition employed along the seabed was shown to be important. Convective overturn was substantially increased if backward dispersion of salt into the aquifer from along the outflowing portion of the seabed boundary was prevented. Overall, the results demonstrated a strong dependence of convective overturn on the aquifer dispersivities, suggesting that results from numerical simulations are problematic to apply to real aquifer systems that typically exhibit uncertain, scale-dependent dispersion properties.

The molecular immune response of the pulpal tissue during chronic carious infection is poorly characterized. Our objective was to examine the expression of potential molecular mediators of pulpal inflammation, correlate their levels with disease severity, and determine the cellular localization of key molecules. Results indicated that there was significantly increased transcriptional activity in carious compared to healthy pulp, and the increase correlated positively with disease severity. Semiquantitative reverse transcriptase PCR analysis in 10 carious and 10 healthy pulpal tissue samples of the S100 family members S100A8, S100A9, S100A10, S100A12, and S100A13; the cytokines tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), IL-8, IL-6, and epithelial cell-derived neutrophil attractant 78 (ENA-78); and the structural protein collagen-1α indicated that all genes tested, with the exception of S100A10, were more abundantly expressed in carious teeth. In addition, we found that the closer the carious lesion front was to the pulpal chamber the higher the expression was for all genes except S100A10. Multiple-regression analysis identified a significant positive correlation between the expression levels of S100A8 and IL-1β, ENA-78, and IL-6 and between collagen-1α and S100A8, TNF-α, IL-1β, IL-8, IL-6, and ENA-78. Immunohistochemical studies in carious pulpal tissue indicated that S100A8 and the S100A8/S100A9 complex were predominantly expressed by infiltrating neutrophils. Gene expression analyses in immune system cells supported these findings and indicated that bacterial activation of neutrophils caused upregulation of S100A8, S100A9, and S100A13. This study highlights the complex nature of the molecular immune response that occurs during carious infection.

Objective : Transforming growth factor-β (TGF-β) regulates odontoblast differentiation and stimulates dentine extracellular matrix synthesis. However, until recently, the molecular mechanisms of action of TGF-β have been unknown. Smad proteins have recently been identified as intracellular signalling mediators of TGF-β. In this study, we characterise the role of Smad proteins as mediators of TGF-β in a mouse odontoblast cell line MDPC-23. Methods : Transcription of Smads was detected by RT-PCR. The change of intracellular location of Smad proteins treated by TGF-β1 was evaluated immunocytochemically. Smad function and its role in transcription of dentin sialophosphoprotein (DSPP) were investigated in cotransfection experiments using promoter-luciferase reporter gene constructs. Results : MDPC-23 cells expressed Smad2, Smad3 and Smad4 mRNA. Endogenous Smad2, Smad3 and Smad4 rapidly translocated from the cytoplasm into the nucleus in response to TGF-β1. The activity of the TGF-β-responsive p3TP-Lux reporter construct was stimulated by 12.7-fold with TGF-β1 treatment. Over-expression of wild-type Smad3 promoted TGF-β1-induced luciferase activity, whereas dominant negative Smad3 inhibited it. TGF-β1 also inhibited the activity of DSPP promoter luciferase reporter construct containing the sequence between −791 bp and +54 bp of the mouse DSPP gene. Over-expression of wild-type Smad3 potentiate the inhibitory effect of TGF-β1 on transcriptional regulation of DSPP, while dominant negative Smad3 decreased the effect. In contrast to Smad3, wild-type Smad2 or its dominant negative mutant had little effect on TGF-β1 regulation of the promoter activity of DSPP. Conclusions : Smad2, Smad3 and Smad4 are present and activated by TGF-β1 in MDPC-23 cells. The Smad pathway is functional in these cells and Smad3 appears to be involved in down-regulation of DSPP by TGF-β1. These findings raise the possibility that Smad signalling plays a role in dentinogenesis.

Odontoblasts produce most of the extracellular matrix (ECM) components found in dentin and implicated in dentin mineralization. Major differences in the pulp ECM explain why pulp is normally a non-mineralized tissue. In vitro or in vivo, some dentin ECM molecules act as crystal nucleators and contribute to crystal growth, whereas others are mineralization inhibitors. After treatment of caries lesions of moderate progression, odontoblasts and cells from the sub-odontoblastic Höhl’s layer are implicated in the formation of reactionary dentin. Healing of deeper lesions in contact with the pulp results in the formation of reparative dentin by pulp cells. The response to direct pulp-capping with materials such as calcium hydroxide is the formation of a dentinal bridge, resulting from the recruitment and proliferation of undifferentiated cells, which may be either stem cells or dedifferentiated and transdifferentiated mature cells. Once differentiated, the cells synthesize a matrix that undergoes mineralization. Animal models have been used to test the capacity of potentially bioactive molecules to promote pulp repair following their implantation into the pulp. ECM molecules induce either the formation of dentinal bridges or large areas of mineralization in the coronal pulp. They may also stimulate the total closure of the pulp in the root canal. In conclusion, some molecules found in dentin extracellular matrix may have potential in dental therapy as bioactive agents for pulp repair or tissue engineering.

In 1992 the Australian Government adopted a policy on the quality use of medicines, or QUM.1 The policy aimed to...

A review of the published international literature was undertaken to investigate whether dehydration is a risk factor for dental disease. Published evidence of associations between saliva and dental disease and between saliva and dehydration was observed, but the precise nature of these associations is unclear and no evidence of a direct link between dehydration and dental disease was found. It is concluded that no direct link between dehydration and dental disease has been proven, although there is considerable circumstantial evidence to indicate that such a link exists.

We examine observational constraints on chaotic inflation models in the Randall-Sundrum Type II braneworld. If inflation takes place in the high-energy regime, the perturbations produced by the quadratic potential are further from scale-invariance than in the standard cosmology, in the quartic case more or less unchanged, while for potentials of greater exponent the trend is reversed. We test these predictions against a data compilation including the WMAP measurements of microwave anisotropies and the 2dF galaxy power spectrum. While in the standard cosmology the quartic potential is at the border of what the data allow and all higher powers excluded, we find that in the high-energy regime of braneworld inflation even the quadratic case is under strong observational pressure. We also investigate the intermediate regime where the brane tension is comparable to the inflationary energy scale, where the deviations from scale-invariance prove to be greater., 5 pages RevTeX4 file with three figures incorporated. Minor changes to match version accepted by Physical Review D

To investigate the spectrum of toxicity of moclobemide overdose, the occurrence of serotonin toxicity, and to estimate toxicokinetic parameters.All moclobemide overdoses presenting over a 10-year period to the Hunter Area Toxicology Service were reviewed. Clinical features, complications, length of stay (LOS) and intensive care (ICU) admission rate were extracted from a standardized, prospectively collected database. Comparisons were made between moclobemide alone and moclobemide with a serotonergic coingestant poisoning. Serotonin toxicity was defined by a combination of Sternbach's criteria and a clinical toxicologist's diagnosis. In five patients serial moclobemide concentrations were measured. Time to maximal plasma concentration (Tmax), peak plasma concentration (Cmax) and terminal elimination half-lives were estimated.Of 106 included patients, 33 ingested moclobemide alone, 21 ingested moclobemide with another serotonergic agent (in some cases in therapeutic doses) and 52 ingested moclobemide with a nonserotonergic agent. Eleven (55%) of 21 patients coingesting a serotonergic drug developed serotonin toxicity, which was significantly more than one (3%) of 33 moclobemide-alone overdoses (odds ratio 35, 95% confidence interval 4, 307; P0.0001). In six of these 21 cases severe serotonin toxicity developed with temperature38.5 degrees C and muscle rigidity requiring intubation and paralysis. The 21 patients had a significantly increased LOS (34 h) compared with moclobemide alone overdoses (12 h) (P0.0001) and a significantly increased ICU admission rate of 57% vs. 3% (P0.0001). Time to peak plasma concentration was delayed in two patients where prepeak samples were obtained. Cmax increased slightly with dose, but all three patients ingestingor = 6 g vomited or had charcoal. The mean elimination half-life of moclobemide in the five patients in whom serial moclobemide concentrations were measured was 6.3 h and elimination was first order in all cases. There was no evidence of a dose-dependent increase in half-life.The effects of moclobemide alone in overdose are minor, even with massive ingestions. However, moclobemide overdose in combination with a serotonergic agent (even in normal therapeutic doses) can cause severe serotonin toxicity. The elimination half-life is prolonged by two to four times in overdose, compared with that found in healthy volunteers given therapeutic doses. This may be a result of wide interindividual variation in overall elimination, also seen with therapeutic doses, but appears not to be due to saturation of normal elimination pathways.

Clinicians have few quantitative studies that rank the in vivo pulp capping effects of commonly used restorative materials. These factors were investigated to provide guidance to clinicians.One hundred sixty-one standardized pulp-exposed cavities were prepared in nonhuman primate teeth. Exposed pulps were capped with calcium hydroxide, resin-modified glass-ionomer cements, and resin composites. Teeth were collected from 7 to 720 days to observe a full range of responses. Pulpal reactions were categorized according to the standards set by the International Standards Organization. Bacteria were detected with McKay's stain.The incidence of bacterial microleakage was 19.7% with resin composite, 21.1% with resin-modified glass-ionomer cement, and 47.0% with calcium hydroxide. The severity of pulpal inflammation increased with the presence of bacteria or tunnel defects. The severity of pulpal inflammation prevented dentinal bridge formation at varying levels: slight for resin composite and resin-modified glass-ionomer cement, and severe with calcium hydroxide. The incidence of severe inflammation or pulpal necrosis was 7.9% with resin composite, 10.6% with calcium hydroxide, and 10.5% with resin-modified glass-ionomer cement. Other variables, such as pulpal exposure width and tertiary dentin formation, were not highly correlated to pulpal inflammation.Pulp capping with resin composite provided the lowest incidence of bacterial microleakage, the lowest levels of pulpal inflammation, and the lowest incidence of necrosis.

Knowledge of the molecular events that occur in carious disease has so far been constrained due to difficulties in obtaining sufficient quantities of the dental tissues and cells involved. Our histological findings indicate that a pulp-odontoblast cellular complex can be obtained from carious and healthy human teeth when exposed to low-temperatures prior to pulpal extirpation and from rodent teeth processed at room-temperature. In contrast, pulpal tissue extracted from room-temperature processed human teeth and low-temperature processed rodent teeth resulted in the odontoblast layer remaining attached to the pulp chamber. Semi-quantitative RT-PCR (sq-RT-PCR) analysis confirmed that markers previously shown to be preferentially expressed in odontoblasts, namely dentin sialophosphoprotein (DSPP) and Nestin, amplified more readily from the extracted pulp-odontoblast complex, as compared to pulpal tissue alone, in both human and rodent samples. Subsequent gene expression analysis of collagen-1alpha and collagen-3alpha indicated levels were significantly higher in carious pulpal tissue. In addition, analysis characterising the expression of members of the transforming growth factor and bone morphogenic protein families and their receptors indicated in general, that these genes were expressed by healthy odontoblasts and up-regulated in both pulpal cells and odontoblasts in response to carious injury. Use of this temperature-sensitive dental tissue preparation procedure allows detection of differential gene expression in odontoblasts and other pulpal cells in healthy and carious tissue.

We have performed a systematic review of all new serum and urinary paraproteins detected over a six year period in an immunodiagnostic laboratory serving a population of 400,000 people. Clinical diagnoses and associated laboratory features were ascertained from a computerized laboratory database or from clinical notes. Over the period of study, serum or urine paraproteins were detected in 613 new patients. These consisted of 568 patients with serum paraproteins and 45 patients with urinary monoclonal free light chain (in the absence of a serum paraprotein). These paraproteins occurred more commonly in males and the frequency increased with age. Approximately 30% of the serum paraproteins and 60% of urinary monoclonal free light chain were associated with B cell lymphoproliferative disorders (multiple myeloma, plasmacytoma, Waldenstrom's macroglobulinemia, non-Hodgkins lymphoma, chronic lymphocytic leukemia, etc) with the remainder being labeled as monoclonal gammopathies of uncertain significance (MGUS). At clinical presentation, patients with lymphoproliferative disorders tended to have higher levels of paraprotein, B2 microglobulin, the presence of free urinary light chain and demonstrated molecular size heterogeneity of the paraprotein but there was considerable overlap. A good correlation was noted between paraprotein concentration and viscosity in most patients. In conclusion paraproteins were most frequently encountered in the context of a gammopathy of uncertain significance. Features which suggested lymphoproliferative disorders included higher levels of serum paraprotein (15 g/l), elevated levels of B2-microglobulin and the presence of urinary free high chain. However, as much overlap was seen with patients with MGUS, regular monitoring of paraprotein level is considered mandatory in the management of these patients.

The importance of pulp capping variables which mediate pulp repair activities and dentin bridge formation following pulp exposure are not well understood. Consequently, the aim of this study was to investigate the effects of pulp capping variables on tertiary dentin bridge formation.Calcium hydroxide [Ca(OH)2], resin-modified glass-ionomer (RMGI) and resin-based composite (RBC) were used to restore pulp exposures prepared in 161 nonhuman primate teeth, according to ISO usage guidelines. Teeth were collected from between 7 and 720 days to observe the pulp repair activities leading to dentin bridge formation. Bacteria were detected using McKays stain. Pulp activity was categorized histomorphometrically using ISO standards, and analyzed statistically using ANOVA statistics.The pulp capping variables in order of their relationship to dentin bridge area, from the most important to the least important were: time elapsed since pulp capping (P = 0.0009), pulp capping materials (P = 0.0252), bacterial microleakage (P = 0.0358) and area of operative debris in the dentin bridge (0.0362). A further 10 pulp capping variables were found to be less important. Relationships between pulp capping materials, operative debris, tunnel defects, bacterial microleakage, inflammation and dentin bridge formation were observed. Bacteria contaminated 18.6% of RBC, 22.2% of RMGI and 47.0% of Ca(OH)2 capped pulps.

Objectives. The purpose of this study is to compare and contrast differences of pulp responses between non-exposed and exposed cavity preparations in terms of inflammation, frequency of bacterial microleakage, odontoblast and odontoblastoid cell numbers, and tertiary dentine formation. Methods. Class V non-exposed cavities (n=161) and exposed cavities (n=161 teeth) were prepared in non-human primate teeth. Cavities were restored with calcium hydroxide [Ca(OH)2], resin modified glass ionomer, or resin composite. Following extraction (7–730 days), bacteria were detected with McKays stain and pulp reactions were categorized according to ISO guidelines. Teeth were analyzed histomorphometrically and statistically using analysis of variance tests. Results. Exposed cavities in comparison with non-exposed cavities were found to have more severe inflammation (p=0.0001), greater quantities of tertiary dentine (p=0.0001), and an increased frequency of bacterial microleakage (p=0.0034). The density of odontoblastoid cells beneath pulp exposed tertiary dentine was found to be 47.8% of odontoblast cell density beneath non-exposed dentine (p=0.0001). Conclusions. The restoration of exposed cavity preparations is associated with more traumatic pulp injury and repair responses. Consequently, efforts should be made to minimize iatrogenic dentine removal during cavity preparation and the creation of pulp exposures whenever possible.

The purpose of this study was to evaluate pulpal responses to the use of four resin composite materials as direct pulp capping agents. The importance and effects of individual pulp capping variables are not well understood; consequently histomorphometric analysis was used to analyze these variables.Two hundred fifty standardized pulp-exposed cavities were prepared in nonhuman primate teeth. Exposed pulps were capped with calcium hydroxide and multistep and self-etching primer resin composites. Teeth were collected from 3 to 60 days to observe pulpal reactions. Following perfusion fixation, tissues were demineralized, sectioned, stained, and histomorphometrically measured. Bridge area, diameter of pulpal exposure, and cavity floor width were measured. Tunnel defects, operative debris, and pulpal inflammation were graded according to defined criteria.The variables correlated to dentinal bridge area were, in decreasing order of significance, time elapsed since exposure, diameter of pulpal exposure, pulp capping material, and tunnel defects. The variables correlated to pulpal inflammation were the type and curing of pulp capping material. Other variables were not statistically significant.Pulp capping with resin composite materials provided acceptable pulpal inflammatory and dentinal bridge repair responses, comparable with those of calcium hydroxide. Although resin composites are promising as direct pulp capping agents, further investigations are required to optimize their application protocols to reduce the penetration of potentially cytotoxic monomers into pulpal tissue.

To investigate pulpal injury by measuring odontoblast numbers, and pulp dentin repair activity by measuring reactionary dentin area, in relation to the remaining dentin thickness (RDT) of cavity preparations in 217 human teeth.Cavities were restored with adhesive bonded composite, resin-modified glass-ionomer cement, zinc oxide-eugenol or calcium hydroxide materials. The teeth were extracted for orthodontic reasons between 20-381 days post-operatively, and odontoblast numbers and reactionary dentin area were analyzed histomorphometrically, and statistically using ANOVA.Reactionary dentin deposition was observed beneath cavities with a RDT above 0.5 mm as well as beneath cavities with a RDT below 0.25 mm; however maximal reactionary dentin appeared to be beneath cavities with an a RDT between 0.5-0.25 mm (P= 0.0001). The area of reactionary repair was also influenced by the choice of restoration material (P= 0.0385) from greatest to least; calcium hydroxide, composite, resin-modified glass-ionomer cement and zinc oxide-eugenol. Odontoblast numbers were maintained beneath cavities with a RDT above 0.25 mm, cavities placed closer to the pulp appeared to injure underlying odontoblasts, reducing their numbers (P= 0.0001). The choice of cavity restoration material also influenced the survival of underlying odontoblasts (P= 0.0061).

The number of older patients requiring restorative treatment are likely to increase due to improvements in oral health and increased longevity. However, aging odontometric data are lacking. The aim of this study was to determine possible changes in pulp cell density, pulp area, and dentinal thickness with age.Incisors (50), canines (39), premolars (51), and molars (7) extracted from 60 patients aged between 10 and 59 years, were analyzed histomorphometrically for cell density (odontoblasts, subodontoblasts, and pulp core fibroblasts) and dentinal thickness.With increasing patient age, in both crown and root aspects of teeth, dentinal thickness increased (P.001), while the density of odontoblasts (P.001), subodontoblasts (P = 0.001), and pulp fibroblasts (crown, P.011; root, P =.0015) decreased. The degree of age-related changes in teeth appeared to be asymmetrical, with decreases in the root being greater than in the crown. At all ages pulp cell densities, including odontoblasts, within the crown were greater than in the root (P.001), even though the calculated rate of dentinal deposition was greatest in the root.Decreases in pulp cell density may reduce pulp repair activity after restorative treatments, although increases in dentinal thickness may aid pulp protection. An understanding of these age-related changes will influence the provision of restorative and endodontic care and benefit older patients.

Close regulation of odontoblast differentiation and subsequent secretory activity is critical for dentinogenesis during both embryogenesis and tissue repair. Some dental papilla cells achieve commitment and specific competence, allowing them to respond to epithelially derived inductive signals during the process of odontoblast differentiation. Temporo-spatial regulation of odontoblast differentiation is dependent on matrix-mediated interactions involving the basement membrane (BM). Experimental studies have highlighted the possible roles of growth factors in these processes. Regulation of functional activity of odontoblasts allows for both ordered secretion of the primary dentin matrix and maintenance of vitality and down-regulation of secretory activity throughout secondary dentinogenesis. After injury to the mature tooth, the fate of the odontoblast can vary according to the intensity of the injury. Milder injury can result in up-regulation of functional activity leading to focal secretion of a reactionary dentin matrix, while greater injury can lead to odontoblast cell death. Induction of differentiation of a new generation of odontoblast-like cells can then lead to reparative dentinogenesis. Many similarities exist between development and repair, including matrix-mediation of the cellular processes and the apparent involvement of growth factors as signaling molecules despite the absence of epithelium during repair. While some of the molecular mediators appear to be common to these processes, the close regulation of primary dentinogenesis may be less ordered during tertiary dentinogenic responses.

Aim Cavity preparation and restoration variables have an uncertain relationship to pulp injury and repair responses. The purpose of this paper is to determine the importance of cavity preparation and restoration variables, by ranking them according to their effect on pulp injury (odontoblast survival) and pulp repair (reactionary dentine secretion). Method The seven studies reviewed are all based on the protocols described by Murray, Smith and colleagues in 2000 and 2001. Results The studies reviewed provide new perspectives on the importance of cavity preparation and restoration variables in mediating pulp activity. Conclusions The onset of post-operative complications may be most productively minimised by focusing practitioner attention to aspects of treatment highlighted in this review.

Objectives : The incidence of bacterial microleakage, pulp inflammation and necrosis associated with dentine etching treatments prior to restoration are not known. Consequently, to resolve some of the controversy surrounding the effects and importance of vital dentine etching, the authors investigated these factors. Methods : 110 standardised class V cavities were cut into buccal dentine, without exposing the pulp of teeth scheduled for extraction for orthodontic reasons. Cavities were either left unetched, or etched with the non-equivalent treatments of phosphoric acid gel for 60 s or Ethylenediaminetetraacetic acid (EDTA) for 30 s, prior to placement of composite resin. Teeth were collected and pulp responses were evaluated according to ISO guidelines, using pathohistomorphometric analysis and ANOVA statistics. Results : Etching was found to be correlated to bacterial microleakage ( p =0.0001) and tertiary dentine formation ( p =0.0023). Bacterial microleakage was correlated to inflammatory activity ( p =0.0001). The frequency of bacterial microleakage was: no etching (65%), EDTA (51%) and phosphoric acid (PA) (20%). Significance : Vital dentine etching treatment is of extreme importance for the placement of RC to minimise bacterial microleakage. PA etching proved to be more effective at preventing bacterial microleakage than non-etching, and etching with EDTA.

Objectives: To derive indicators of quality prescribing by Australian general practitioners based on Health Insurance Commission (HIC) data and assess the influence of incomplete capture of data on under-copayment drugs on the validity of these indicators. Design: Two expert groups proposed prescribing indicators that can be derived from aggregate prescribing data, and which reflect important clinical or costeffectiveness issues. Indicators were examined using HIC data and compared with national prescribing trends over time using Australian Statistics on Medicines. The effect of incomplete data capture on indicator interpretation was examined by stratifying GPs into five strata based on the proportion of concession card holders in their practice. Participants: Approximately 14 000 Australian GPs providing 1500 Medicare services per year. Main outcome measures: Measures of prescribing for individual GPs (based on HIC data 1993–1997). Results: Forty-three potentially useful indicators were identified. These covered a fairly narrow range of prescribing activities and many required additional clinical information for interpretation. Indicators based on prescribing rates gave a misleading picture of prescribing trends where the extent of HIC data capture changed over time. Indicators expressed as ratios that reflected choice of agent within a drug class were less affected by incomplete data capture. Conclusions: Indicators of quality prescribing can be derived from HIC data. However, indicators for under-copayment drugs that represent prescribing rates may unfairly classify doctors practising in areas of socioeconomic disadvantage or high morbidity as “high prescribers”. Ratio indicators are more robust, and may be more valid prescribing measures. If HIC data are to be used to monitor the quality of

Objectives The aims of the present study were first to investigate the dietary intake pattern of UK teenagers and secondly to determine the relationship, if any, between dental erosion and dietary intake in these children. Methods The study group consisted of a cluster random sample of 14-year-old school children in Birmingham, UK: 418 children were examined from 12 different schools; 209 were male and 209 female. Data on the rate and frequency of consumption of drinks, foods, and fruits were obtained from a self-reported questionnaire supplemented by a structured interview. The data were analysed using SPSS with Chi-square, and Spearman correlation analysis. Results Over 80% of the teenagers regularly consumed soft drinks but approximately half of these children had a relatively low weekly consumption. However, 13% and 10% respectively had more than 22 intakes per week of cola and other carbonated drinks. Almost a quarter of these 14-year-olds had alcoholic drinks, with significantly more males than females involved (Chi-square P < 0.05). Girls had a greater intake of fruits. Statistically significant correlations were found between the prevalence of erosion and the consumption of soft drinks, carbonated beverages, alcohol drinks, fresh fruits, Vitamin-C tablets and foodstuffs (Spearman correlation analysis P < 0.05). Conclusion It was concluded that consumption particularly of soft drinks was high and common in teenage school children in Birmingham, UK. In addition there was a relationship between dental erosion and acidic dietary intake. Further investigation of the erosive potential of these drinks and foods is required.

Background Each year, about 90 million new restorations are placed in the United States and 200 million are replaced. Controversy surrounds the pulpal reactions and frequency of bacterial microleakage associated with common restorative materials. The authors investigated and compared pulpal reactions to different types of restorative materials. Methods Two hundred seventy-two teeth with standardized rectangular Class V unexposed cavities were restored with resin-based composite bonded to dentin; resin-based composite bonded to enamel; resin-modified glass ionomers, or RMGI; amalgam lined with zinc polycarboxylate, or ZnPC; amalgam lined with calcium hydroxide, or Ca(OH) 2 ; or zinc oxide– eugenol, or ZnOE. Teeth were extracted for orthodontic reasons between 20 and 381 days later. The authors categorized pulpal responses according to standards set by the Federation Dentaire Internationale and the International Organization for Standardization. Bacteria were detected using Brown-Brenn–stained sections. Pulpal responses were evaluated using histomorphometric analysis and analysis of variance statistics. Results The results showed that RMGI was the best material for preventing bacterial microleakage, and resin-based composite bonded to enamel was the worst. In regard to minimizing pulpal inflammatory activity, ZnOE was the best material and resin-based composite bonded to enamel was the worst. In terms of maximizing odontoblast survival beneath deep cavity preparations, Ca(OH) 2 , was the best material and RMGI was the worst. Conclusions The results show that bacterial microleakage, pulpal injury and repair responses varied widely with different restorative materials. Clinical Implications The authors recommend that RMGI be used to restore teeth with cavities that are shallow to moderate in depth, with the floor of deep cavities being lined with Ca(OH) 2 before the teeth are restored with RMGI.

Objectives To establish the prevalence of erosion in a cluster random sample of 14- year-olds in Birmingham UK. To determine whether socioeconomic group influences the prevalence of erosion. Methods The study group consisted of a cluster random sample of 14-year-old school children in Birmingham UK: 418 children were examined from 12 different schools; 209 were male and 209 female. The level of tooth wear was recorded using a modification of the (TWI) index of Smith and Knight (1984). The ACORN classification was used to assess the socioeconomic status of all children. Results Results showed that 48% of the children had low erosion, 51% had moderate erosion and only 1% had severe erosion. There were statistically significant differences between males and females; more males had buccal/ labial and lingual / palatal tooth surface erosion than females (Chi-square analysis P < 0.001). There was also significantly more erosion observed in teenagers in the lowest socioeconomic categories. Conclusion It was concluded that moderate levels of dental erosion are common in 14-year-old school children and this may lead to increasing clinical problems. There was significantly more erosion in children from low socioeconomic groups. Possible aetiological factors need to be investigated further.

The purpose of this work was to develop a tooth slice organ culture method to assess the response of the cells of the dental pulp to commonly used dental materials and products. Wistar rat tooth slices were grown in culture for two and ten days in the presence of dental materials. After culture, the tooth tissues were processed and the responses of the pulpal cells were analysed histomorphometrically. Cytotoxic cell destruction was observed following the direct application of test materials to tooth slices (n = 298) after 10 days in culture (MANOVA, P = 0.0001), whilst the restoration of prepared deep dentine cavities (n = 30), with test products, did not result in a significant amount of pulpal injury (MANOVA, P = 0.287). In rank order of causing pulpal injury, the test materials from the most to the least cell destructive, was; Salicylic acid. Calcium hydroxide, Kalzinol zinc oxide eugenol, high-mercury Amalgam, Prime & Bond, Dycal, Barium sulphate, Hypocal, Scotchbond, Calasept, Life and One-step. Tooth slice organ culture, provided a cytotoxicity screening method for dental materials, bearing a closer physiological resemblance to the clinical situation than cell culture screening methods. Tooth slice culturing may have the potential to replace some types of in vivo animal experimentation, as there is a clear need to reduce this form of testing.

Each year in the United States, the success of 10 million surgically restored carious lesions depends on a favorable tertiary dentin repair response to preparation, restoration and patient factor variables. The authors investigated the relationship between these variables and dentinal response.Standardized rectangular Class V restoration preparations were cut into the buccal dentin of intact first or second premolars of 27 patients without exposing the pulp and were restored. The patients were between 9 and 17 years of age. The treated teeth were scheduled for extraction for orthodontic reasons. After tooth extraction, the tertiary dentin was analyzed histomorphometrically.The area of tertiary reactionary dentin was found to be correlated using linear regression analysis of variance with restoration residual dentin thickness (P = .0024), age of the patient (P = .0045), restoration floor surface area (P = .0266) and restoration width (P = .0415). The authors did not find a correlation with the premolar position (P = .0594), sex of the patient (P = .650), pulpal inflammatory reaction (P = .613) or the time elapsed since surgery (P = .531). Restoration with zinc oxide eugenol was found to negatively influence tertiary dentin matrix secretion (post hoc analysis of variance, P = .030).The age of a patient at treatment, the choice of restorative material and the size of the restoration preparation are all factors that can positively or negatively affect the pulpal repair response.Age of the patient affects dentin repair capacity and may be a factor in treatment planning decisions. Minimizing the cutting of dentin, especially the width and base of the preparation, reduces the probability of recurrent pulpal complications.

In 2006 it became legal under Britain's 'non-medical prescribing programme' for nurses 'to prescribe any licensed...

The recommended treatment of human chloroquine poisoning is diazepam and adrenaline but neither has been evaluated in controlled clinical trials. We investi gated whether diazepam provided any added benefit over barbiturate anaesthesia and whether the protective effect of catecholamines in chloroquine poisoning was mediated through alpha or beta receptor stimulation. Rats, anaesthetised with thiobutobarbitone had a continuous intravenous infusion of 3 mg/kg/min of chlor oquine. This caused a steady decline in pulse rate and blood pressure. When diazepam (3 mg/kg iv) was admi nistered 5 -10 min later, heart rates decreased at a faster rate (P=0.005), blood pressure was consistently lower (P=0.01) and there was a shorter time to arrhythmias and death (P < 0.05). Adrenergic agents were given by titration to attempt to maintain mean blood pressure > 75 mmHg. Compared with the phenylephrine (selective alpha agonist) group, the group treated with isoprenaline (selective beta agonist) had faster heart rates which decreased more slowly (P < 0.0001), higher blood pressure (P=0.005) and longer time to arrhythmias and death (P=0.005). Adrenaline and noradrenaline had intermedi ate effects. Thus beta agonist effect appears to explain the beneficial effects of adrenaline but alpha agonist activity may be harmful. This animal work suggests that a combination of barbiturate anaesthesia and isoprenaline may be better than the diazepam and adrenaline in combatting the effects of chloroquine.

Irrational prescribing is a habit which is difficult to cure. However, prevention is possible and for this reason the WHO Action Programme on Essential Drugs aims to improve the teaching of pharmacotherapy to medical students. The impact of a short problem-based training course in pharmacotherapy, using a WHO manual on the principles of rational prescribing, was measured in an international multi-centre randomised controlled study of 219 undergraduate medical students in Groningen (Netherlands), Kathmandu (Nepal), Lagos (Nigeria), Newcastle (Australia), New Delhi (India), San Francisco (USA), and Yogyakarta (Japan). The manual and the course presented the students, who were about to enter the clinical phase of their studies, with a normative model for pharmacotherapeutic reasoning in which they were taught to generate a "standard" pharmacotherapeutic approach to common disorders, resulting in a set of first-choice drugs called P(ersonal)-drugs. The students were then taught how to apply this set of P-drugs to specific patient problems on the symptomatic treatment of pain, using a six-step problem-solving routine. The impact of the course was measured by tests before training, immediately after, and six months later. After the course, students from the study group performed significantly better than controls in all patient problems presented (p0.05). The students not only remembered how to solve old problems, but they could also apply their skills to new problems. Both retention and transfer effect were maintained at least six months after the training session in all seven medical schools. In view of the impossibility of teaching students all basic knowledge on the thousands of drugs available, this approach seems to be an efficient way of teaching rational prescribing. However, the method should be accompanied by a change in teaching methods away from the habit of transferring knowledge about the drugs towards problem-based teaching of therapeutic reasoning.

SUMMARY 1. Pretreatment with intravenous WEB-2086 (0.5 mg/ kg; an antagonist of the actions of platelet activating factor; PAF) with or without indomethacin (2 mg/ kg) failed to prevent or modify the fall in blood pressure following unclipping of the renal artery of anaesthetized two-kidney, one-clip hypertensive rats. 2. The same medications given to two other groups of rats 60 min after unclipping when the blood pressure had fallen to stable levels failed to reverse the fall. 3. Despite evidence that both prostanoids and PAF can be detected in increased amounts in renal venous blood after unclipping, they do not appear to mediate the reduction in blood pressure in this model of reversible hypertension.