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Background Human papillomavirus (HPV) infection is known to promote the development of mucosal squamous cell carcinoma (mSCC), including pathologically high-grade lesions, but its role in cutaneous squamous cell carcinoma (cuSCC) remains unclear, particularly in lesions that are considered high risk. Objective We aimed to determine whether enhanced HPV transcriptional activity can be detected in high-risk cuSCC samples compared with low-grade SCC samples or normal skin. Methods We performed RNA sequencing of cuSCC across 23 risk-stratified skin lesions. A subset of samples was tested for the presence of HPV DNA. High-quality, non-human reads from each sample group were used for viral analysis using Microbiome Coverage Profiler. Results None of the samples analysed had detectable expression of HPV RNA, while 64% of samples tested positive for HPV DNA. All samples were found to have expression of human endogenous retrovirus, and multiple samples showed expression of other viruses. Conclusions Viral and prophage gene expression can be monitored in cuSCC or normal skin biopsies, yet no sample in our study showed evidence of active HPV gene expression despite evidence of HPV genome presence. This suggests HPV transcription does not play a role in differentiating high-risk cuSCCs from low-risk cuSCCs or normal skin.

Novel polycaprolactone-based polyurethane (PCL-PU) copolymers with hyperelasticity, shape-memory, and ultra-cell-adhesion properties are reported as clinically applicable tissue-regenerative biomaterials. New isosorbide derivatives (propoxylated or ethoxylated ones) were developed to improve mechanical properties by enhanced reactivity in copolymer synthesis compared to the original isosorbide. Optimized PCL-PU with propoxylated isosorbide exhibited notable mechanical performance (50 MPa tensile strength and 1150% elongation with hyperelasticity under cyclic load). The shape-memory effect was also revealed in different forms (film, thread, and 3D scaffold) with 40%-80% recovery in tension or compression mode after plastic deformation. The ultra-cell-adhesive property was proven in various cell types which were reasoned to involve the heat shock protein-mediated integrin (α5 and αV) activation, as analyzed by RNA sequencing and inhibition tests. After the tissue regenerative potential (muscle and bone) was confirmed by the myogenic and osteogenic responses in vitro

Patients present to the emergency department in various stages of chronic illness. Advance directives (ADs) aid emergency physicians in making treatment decisions, but only a minority of Americans have completed an AD, and the percentage of those who have discussed their end‐of‐life wishes may be even lower. This article addresses the use of common ADs and roadblocks to their use from the perspectives of families, patients, and physicians. Cases to examine new approaches to optimizing end‐of‐life conversations in patients who are chronically ill, such as the Improving Palliative Care in Emergency Medicine Project, a decision‐making framework that opens discussion for patients to gain understanding and determine preferences, and the Brief Negotiated Interview, a 7‐minute, scripted, motivational interview that determines willingness for behavior change and initiates care planning, are used.

This study aims to evaluate the viscoelastic and chemical properties of dentine after different durations of exposure to 5.25% NaOCl, 17% EDTA and Ca(OH)2 solutions, and NaOCl in alternating combination with EDTA. Standard dentine bars were randomly assigned to: (i) formal-saline control-1; (ii) NaOCl; (iii) EDTA; (iv) NaOCl/EDTA; (v) formal-saline control-2; (vi) Ca(OH)2 pH 12.6; and (vii) Ca(OH)2 pH 9.8. Groups 1--4 underwent 10 min cycles of soaking and dynamic mechanical analysis up to 120 min. Groups 5-7 underwent similar tests at days 7, 14, 28 and 84. FTIR spectra of dentine discs exposed to the same regimens assessed surface chemistry. NaOCl or Ca(OH)2 (pH 12.6) solutions reduced the organic (N-H[1], N-H[3], C=0) peak components of dentine. This study demonstrated that accumulative damage of dentine could be facilitated by alternated exposure to NaOCl and EDTA. Exposure of dentine to Ca(OH)2 (pH12.6) for 7 days reduced viscous behaviour, inferring increased potential for fatigue failure.

The aims were to compare the physico-chemical properties (zeta-potential, wettability, surface free energy) of stereolithography materials (STL) (Photopolymer, Accura) to dentine and to evaluate the potential of each material to develop Enterococcus faecalis biofilm on their respective surfaces. Eighteen samples of each test material (Photopolymer, Accura, dentine) were employed (total n = 54) and sectioned to 1 mm squares (5 mm x 5 mm) (n = 15) or ground into a powder to measure zeta-potential (n = 3). The zeta-potential of the powder was measured using the Nano-Zetasizer technique. The contact angle (wettability, surface free energy tests) were measured on nine samples using goniometer. The biofilm attachment onto the substrate was assessed on the samples of each material using microscope and image processing software. The data were compared using one-way ANOVA with Dunnett post-hoc tests at a level of significance P ≤ 0.05. Both STL materials showed similar physico-chemical properties to dentine. The materials and dentine had negative charge (Accura: −23.7 mv, Photopolymer: −18.8 mv, dentine: −9.11 mv). The wettability test showed that all test materials were hydrophilic with a contact angle of 47.5°, 39.8°, 36.1° for Accura, Photopolymer and dentine respectively, and a surface free energy of 46.6, 57.7, 59.6 mN/m for Accura, Photopolymer and dentine, respectively. The materials and dentine proved suitable for attachment and growth of E. faecalis biofilm with no statistical differences (P > 0.05). Stereolithography materials show similar physico-chemical properties and growth of E. faecalis biofilm to dentine. Therefore, they may be an alternative to tests requiring dentine.

Bioactive glass (BG) is considered an ideal material for haemostasis as it releases Ca2+ ions upon hydration, which is required to support thrombosis. In this study the effect of the presence of the BG nanoparticles in P(3HB) microsphere films on the structural properties, thermal properties and biocompatibility of the films were studied. The nanoscaled bioactive glass with a high surface area was also tested for its in vitro haemostatic efficacy and was found to be able to successfully reduce the clot detection time. In an effort to study the effect of the roughness induced by the formation of HA on the cellular functions such as cell adhesion, cell mobility and cell differentiation, the composite films were immersed in SBF for a period of 1, 3 and 7 days. From the SEM images the surface of the P(3HB)/n-BG composite microsphere films appeared fairly uniform and smooth on day 1, however on day 3 and day 7 a rough and uneven surface was observed. The presence of HA on the composite microsphere films on day 3 and day 7 influenced the surface roughness of the films. However, when the P(3HB)/n-BG composite microspheres with enhanced surface roughness were tested for biocompatibility, reduced amount of protein adsorption and cell adhesion were observed. This study thus revealed that there is an optimal surface roughness for the P(3HB) microsphere films for increased cell adhesion, beyond which it could be deleterious for cell adhesion and differentiation.

Cartilage tissue engineering is an emerging therapeutic strategy that aims to regenerate damaged cartilage caused by disease, trauma, ageing or developmental disorder. Since cartilage lacks regenerative capabilities, it is essential to develop approaches that deliver the appropriate cells, biomaterials and signalling factors to the defect site. Materials and fabrication technologies are therefore critically important for cartilage tissue engineering in designing temporary, artificial extracellular matrices (scaffolds), which support 3D cartilage formation. Hence, this work aimed to investigate the use of poly(3-hydroxybutyrate)/microfibrillated bacterial cellulose (P(3HB)/MFC) composites as 3D-scaffolds for potential application in cartilage tissue engineering. The compression moulding/particulate leaching technique employed in the study resulted in good dispersion and a strong adhesion between the MFC and the P(3HB) matrix. Furthermore, the composite scaffold produced displayed better mechanical properties than the neat P(3HB) scaffold. On addition of 10, 20, 30 and 40 wt% MFC to the P(3HB) matrix, the compressive modulus was found to have increased by 35%, 37%, 64% and 124%, while the compression yield strength increased by 95%, 97%, 98% and 102% respectively with respect to neat P(3HB). Both cell attachment and proliferation were found to be optimal on the polymer-based 3D composite scaffolds produced, indicating a non-toxic and highly compatible surface for the adhesion and proliferation of mouse chondrogenic ATDC5 cells. The large pores sizes (60 - 83 µm) in the 3D scaffold allowed infiltration and migration of ATDC5 cells deep into the porous network of the scaffold material. Overall this work confirmed the potential of P(3HB)/MFC composites as novel materials in cartilage tissue engineering.

The only types of polyhydroxyalkanoates (PHAs) that have been explored for use in nerve regeneration are poly(3-hydroxybutyrate), P(3HB), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (P(3HB-co-3HHx)). However, nerve regeneration induced by these PHAs is inferior to that of autologous nerve grafting. The aim of this work was to study novel PHA blends as resorbable biomaterials for the manufacture of nerve guidance conduits. PHA blend films with varying ratios of poly(3-hydroxyoctanoate)/P(3HB) (P(3HO)/P(3HB)) were produced using the solvent-casting method. Neat films of P(3HO) and P(3HB), along with 25:75, 50:50, and 75:25 blend films of P(3HO)/P(3HB), were characterized with respect to chemical, material, and biological properties. On surface analysis, the blends exhibited higher values of roughness compared with the neat films. The differential scanning calorimetry characterization of the blends confirmed that P(3HO) and P(3HB) formed immiscible blends. FTIR and XRD analysis of the blends showed a decrease in crystallinity along with an increase of the proportion of P(3HO) . However, an increase in the stiffness of the blends was observed when the proportion of P(3HB) increased. Although all of the blends were biocompatible with NG108-15 neuronal cells, the 25:75 P(3HO)/P(3HB) blend showed significantly better support for growth and differentiation of these cells. The mechanical properties of PHA blends correspond to the reported properties of peripheral nerves. Therefore, they could serve as base material for the manufacture of nerve guidance conduits.

Summary This paper presents the structural characterization of melt-quenched titanium metaphosphate glasses having compositions of 0.5P2O5–0.4CaO–(0.1–x)Na2O–xTiO2 (x = 0.00–0.07 mol fraction) by means of x-ray diffraction (XRD) techniques employed under both ambient and high-temperature conditions. Ambient XRD spectra of powdered glass samples revealed the amorphous nature of the glasses, while ambient XRD software analysis of crystallised glass powders provided information regarding the phase transitions in the glass compositions with an increase in the TiO2 content. High-temperature XRD (HT-XRD) contour plots showed good agreement with the results of both ambient XRD and differential thermal analysis, thereby demonstrating the correspondence between three distinct sets of experimental data and allowing us to correlate thermal events with the crystalline phases formed. Thus, the overall results offer interesting clues into the structure of these titanium metaphosphate glasses, which have emerged as major candidates in the biomedical field for use as substrates in the regeneration of hard and soft tissues.

Novel poly(3-hydroxyoctanoate), P(3HO), and bacterial cellulose composites have been developed. P(3HO) is hydrophobic in nature whereas bacterial cellulose is extremely hydrophilic in nature. Therefore, homogenized bacterial cellulose has been chemically modified in order to achieve compatibility with the P(3HO) matrix. Modified bacterial cellulose microcrystals and P(3HO) have been physically blended and solvent casted into two-dimensional composite films. Mechanical characterization shows that the Young's modulus of the P(3HO)/bacterial cellulose composites is significantly higher in comparison to the neat P(3HO) film. The melting temperature (Tm) of the composites is lower while the glass transition temperature (Tg) is higher than the neat P(3HO) film. Also, the composite film has a rougher surface topography as compared to the neat P(3HO) film. A month's in vitro degradation study has been carried out in Dulbeccos modified eagle medium and in phosphate buffer saline. The incorporation of modified bacterial cellulose microcrystal in the P(3HO) film has increased the degradability of the composite film. Finally, in vitro biocompatibility studies using human microvascular endothelial cells established the biocompatibility of the P(3HO)/bacterial cellulose microcrystal films. The cell proliferation was 50–110% higher on the P(3HO)/bacterial cellulose composites as compared to the neat P(3HO) film. Hence, in this study, for the first time, P(3HO)/bacterial cellulose composites have been developed. The addition of bacterial cellulose has resulted in properties that are highly desirable for medical applications including the development of biodegradable stents.

The main hindrance in the use of polyhydroxyalkanoates (PHAs) as a replacement for existing petroleum-based plastics is their high production cost. The carbon source accounts for 50% of the cost for PHA production. Thus, increasing the yield and productivity of PHAs on cheap substrates is an important challenge for biotechnologists to support the commercialization and further applications of these polymers. In this study, we have investigated the use of an agricultural raw material, sugarcane molasses, as the main carbon source for poly(3-hydroxybutyrate) (P(3HB)) production by Bacillus cereus SPV. These studies were carried out in both shaken flasks and 2 L bioreactors. Various conditions were evaluated for their effects on biomass and P(3HB) accumulation. A high polymer yield was obtained, 61.07% dry cell weight (DCW) in a 1 L shaken flask study and 51.37% DCW in a 2 L fermenter study. These yields are 50% higher than previously observed with Bacillus cereus SPV. Hence, the results are encouraging and show that sugarcane molasses are a promising carbon source for an economical and commercially viable production of P(3HB).

The homopolymer poly(3-hydroxyoctanoate), P(3HO) produced from Pseudomonas mendocina using octanoate as carbon feed was studied as a potential biomaterial for soft tissue engineering i.e. as cardiac patch and as matrices for skin tissue engineering. The polymer was fabricated into neat solvent cast films of 5 and 10 wt %. Microstructural studies revealed the films as having smooth surface topography with a root mean square (RMS) value of 0.238 µm. The films also possessed moderate hydrophilicity when compared to other monomers of the PHA family. Stress-strain curves of the films obtained was typical of that of elastomeric polymers. This elastomeric and flexible nature of the films makes them promising candidates for the proposed applications. Biocompatibility studies using the HaCaT keratinocyte cell line showed that the films were able to support the attachment, differentiation and maturation of the HaCaT cells. In vitro degradation studies over a period of 4 months showed that the water absorption and weight loss increased progressively with time for the films. The films underwent hydrolytic degradation initiated on the surface and also showed an ageing effect.

The first South-East European Regional Conference of Psychology was held in Sofia, Bulgaria, from 30 October to 1 November 2009, under the Patronage of the President of Bulgaria and the auspices of the International Association of Applied Psychology (IAAP), the International Union of Psychological Science (IUPsyS), and the International Association for Cross-Cultural Psychology (IACCP), with further financial support provided by the European Federation of Psychologists’ Associations (EFPA) and the European Health Psychology Society (EHPS). The conference was hosted by the Bulgarian Psychological Society under the Conference Presidency of Dr Plamen Dimitrov, who was supported by Professor Sava Djonev as Chair of the Scientific Program Committee. It attracted over 350 participants from 25 countries, including 14 countries from the SEE region and its immediate neighbours. The Scientific Program explored ways and means to promote the role of psychology individually and institutionally at regional and internat...

Understanding tissue response to materials, to enable modulation and guided tissue regeneration is one of the main challenges in biomaterials science. Nowadays polymers, glasses, and metals dominate as biomaterials. Often native properties of those materials are not sufficient and there is a need to combine them, so as to modify and adjust their properties to the application. The primary aim of this study was to improve cell response to polymer (PLDL) using phosphate glass as filler (titanium doped phosphate glass). As a control beta-tricalcium phosphate (TCP) filler was used. Various concentrations of the filler were used (10-40 vol%). Wetting behavior, zeta-potentials, mechanical and thermal properties, and human cells response to the materials were evaluated. Results showed that with increase in glass filler loading wettability improved, zeta-potentials dropped, and increase in stiffness of materials was observed. Importantly cell culture experiments showed more developed and well spread cells on the samples with glass content up to 20 vol%. Cells responded much more positively to the glass filled samples than to TCP filled. However, expression of osteocalcin and osteopontin, proteins that indicate formation of the mineralized structures was positive for all the samples including pure PLDL. It was concluded that due to improved wetting behavior, lower zeta-potentials, and specific chemistry of the glass filler it was possible to alter cells response, improve bioactivity of the polymer, and vary mechanical properties.

Tetracycline, an antibiotic used against a broad range of Gram positive and Gram negative bacteria was encapsulated in microspheres made of poly(3-hydroxybutyric acid) P(3HB), a microbial biodegradable polymer isolated from Bacillus cereus SPV. The drug loaded microspheres were prepared using an oil emulsion technique and compressed uniaxially to produce films. Although the same fabrication conditions were used for preparing the drug loaded and unloaded microspheres, the presence of the drug changed the surface morphology and roughness of the films. The surface morphology of the drug loaded films appeared uneven and coarser and the roughness, with an average root mean square value of 5.89 µm, was significantly higher than that of the unloaded film. The in vitro biocompatibility of the films was investigated using a human keratinocyte cell line (HaCaT) by comparing cell viability on the films to that on conventional tissue culture plastics. Both films appear to support cell growth but cell attachment and percentage cell viability were greater on the drug loaded films (32% of control) compared to the unloaded film (10% of control), possibly as a result of the non-uniform surface morphology and increased roughness of the drug loaded film. Thus, the above results illustrate that the drug loaded films, in addition to being a suitable matrix for drug delivery, represent an improved substrate for keratinocyte cell attachment.

P>AimTo evaluate the effect of irrigation with 5% sodium hypochlorite (NaOCl) alone and in conjunction with 17% ethylenediaminetetraacetic acid (EDTA) on tooth surface strain (TSS) and to analyse the influence of irrigation time, root morphology and dentine thickness.MethodologyThirty-six single-rooted pre-molars with single canals had their crown and enamel reduced and root canals prepared using a standardized protocol. Teeth were grouped according to anatomical criteria and randomly distributed to experimental irrigation groups: (A) saline (negative control); (B) 5% NaOCl (positive control); (C) 5% NaOCl alternated with 17% EDTA. TSS was measured using electrical strain gauges bonded to the cervico-proximal part of the tooth. Teeth, mounted in clear acrylic resin placed in a universal testing machine, were subjected to nine consecutive 10-min irrigation periods followed by non-destructive occlusal loading to record TSS. Statistical analysis was carried out using two-way hierarchical anova and post hoc multiple comparisons.ResultsTwo groups showed an increase in TSS from the baseline (initial 10-min irrigation with saline). Group A showed a negligible reduction of 1.2% (343-339 mu epsilon), which was not statistically significant (P = 0.7). Group B showed a highly significant (P = 0.001) increase in TSS by 53.7% (178-253 mu epsilon), and group C showed a significant (P = 0.02) increase in TSS by 17.4% (163-192 mu epsilon). The rate of change in TSS was significantly different between test groups. The length of the tooth (P = 0.04) as well as the mesio-distal (P = 0.05) width had significant effects on TSS.ConclusionsIrrigation with 5% with or without 17% EDTA increased TSS. The increase was significantly greater with 5% NaOCl alone than with 5% NaOCl alternated with 17% EDTA in contrast to previous findings with longer duration of irrigant exposure. Tooth length and mesio-distal root width significantly contributed to the increase in TSS.

Local delivery of antibiotics may provide the advantage of reducing the potential side effects associated with their systemic administration. This study assessed, in vitro, the antimicrobial efficacy of tetracycline hydrochloride (TCH) adsorbed onto Bio-Oss bone grafts against a range of pathogenic bacteria. Various levels of TCH were adsorbed onto Bio-Oss granules by immersing in TCH aqueous solutions of different initial concentrations for 48 h at room temperature. TCH release was assessed in phosphate buffered saline at 37 degrees C, and its antimicrobial efficacy, up to 96 h, was tested against two Gram-negative bacteria associated with periodontal diseases: Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, and Porphyromonas gingivalis, and one Gram-positive bacterium associated with soft-tissue and bone infections: Staphylococcus aureus. The range of TCH concentrations studied was also assessed for cytotoxicity against osteoblast-like human osteosarcoma cell lines. The amount of TCH adsorbed and released from Bio-Oss was concentration dependent. All TCH adsorbed Bio-Oss resulted in a reduction of A. actinomycetemcomitans, P. gingivalis, and S. aureus and higher concentrations were generally more effective in reducing or eliminating bacterial growth. The proliferation of HOS cells was not substantially reduced except for the maximum concentration of TCH. In addition to its osteoconductive role, TCH adsorbed Bio-Oss could also be functional in negating systemically antibiotic prophylactic treatment in the prevention of implant or biomaterial related infections.

Aim To evaluate the effect of irrigation regimens on tooth surface strain using saline, sodium hypochlorite (3% and 5% NaOCl) and ethylenediaminetetraacetic acid (17% EDTA), individually and in alternating combinations. Methodology Single-rooted premolar teeth with single canals prepared to standardized dimensions were grouped by anatomical features and randomly distributed amongst six experimental groups (n = 12 each). The six groups were: (1) saline; (2) 5% NaOCl; (3) 3% NaOCl; (4) 17% EDTA; (5) 3% NaOCl and 17% EDTA; (6) 5% NaOCl and 17% EDTA. All groups underwent four (group 1) or five (groups 2, 3, 4, 5, 6) sequential 30-min irrigation periods following each of which the tooth was subjected to a standard regime of cyclic, nondestructive, occlusal loading. Tooth surface strain was measured during each loading cycle using electrical strain gauges mounted cervico-proximally. The data were analysed by Hierarchical anova and post hoc multiple comparisons. Results Irrigation with 5% NaOCl alone or alternating with 17% EDTA significantly (P

This work investigated the further development of a well-characterized, contiguous, glass fiber system for regeneration of the hard-soft tissue interface. We evaluated the effect of fiber diameter on human osteoblasts and fibroblasts attachment and viability using ternary glass fibers of the composition 0.48 CaO-0.02 Na(2)O-0.50 P(2)O(5). Fiber diameter significantly influenced cell attachment and survival, with fibers drawn at 800 revolutions per minute found to be optimal. Using a known composition of iron-phosphate glass fibers (composition 0.46 CaO-0.01 Na(2)O-0.03 Fe(2)O(3)-0.50 P(2)O(5)), scaffolds were produced. These scaffolds were incorporated within an open laminar flow culture system to provide nutrients, oxygen, and waste perfusion throughout the culture. The design of the chamber ensured that laminar flow was present, and changes in the differentiation of both osteoblast and fibroblast seeded scaffolds were assessed using quantitative polymerase chain reaction. Our data show that osteoblast and fibroblast differentiation is unaffected or enhanced by laminar flow when compared with static culture conditions. This system can therefore be adapted to construct larger, more complex, three-dimensional iron-phosphate fiber scaffolds for tissue engineering.

To (i) characterise the degradation pattern and ion release characteristics of bioactive glass/polycaprolactone (PCL) composites; (ii) compare the degradation behaviour of composites containing phosphate glass to that of Resilon((R)); and (iii) determine the potential to control the degradation of the composites by modifying the iron content of phosphate glasses.The degradation behaviour of the phosphate glass/PCL samples (n = 3) and that of Resilon((R)) were determined in two aqueous solutions (buffered distilled water, Hanks Buffered Saline Solution) over a 7-day period using weight change measurement, ion chromatography, light microscopy (LM) and scanning electron microscopy (SEM).An initial increase in weight of the samples was followed by loss. All phosphate glass/PCL composites released various amounts of iron, sodium, calcium and phosphate ions into solution. The Resilon((R)) samples released only sodium and calcium ions. The visual methods (LM, SEM) showed distinct precipitate (calcium phosphate) formation on the surface of the phosphate glass/PCL composites but only a faint surface residue on the surface of Resilon((R)).The degradation pattern of the composites containing phosphate glass was different from that of Resilon((R)). The phosphate glass/PCL composites encouraged precipitate formation on the material surface, which may be advantageous in creating a marginal and apical seal.

A highly interconnected porous scaffold made from 45S5 Bioglass® was fabricated by the polymer replica technique and surface functionalized for protein immobilization. Subsequently rat-tail collagen type I was immobilized on the scaffolds. The protein and ion release rates were determined by UV-vis spectroscopy and ion chromatography, respectively, and the impact on hydroxyapatite (HA) formation on the scaffolds upon immersion in SBF was evaluated. It was discovered that the surface functionalization enhanced the stability of the collagen attachment and stability against the increment of pH in a biological environment, resulting in similar collagen release kinetics in solutions of different pH values. Without the surface modification, collagen release was considerably expedited by the increment of pH in a surrounding solution. It was also found that the collagen immobilization does not effect the formation of carbonated HA on the scaffold surface. The stable collagen attachment to the functionalized scaffold makes this approach potentially suitable for improving cell attachment and thus for enhancing the application potential of the scaffold in tissue engineering.

BAckgroundNone of the proposed materials tested for the management of perianal fistulae has proven to be a definitive treatment.AimTo assess a new repair scaffold and drug delivery device conceived to target perianal fistula repair.MethodsPoly(d,l-lactide-co-glycolide) porous microspheres containing either antibacterial silver-releasing degradable phosphate glass or metronidazole were prepared using thermally induced phase separation.ResultsIon- and drug-release profiling of the microspheres revealed continued release of silver ions from microspheres filled with silver-doped phosphate glass and high encapsulation efficiency for metronidazole [78% and 82% for microspheres loaded with 2.5% and 1.3% (w/w), respectively]. Microbicidal activity was confirmed by growth inhibition of bacterial species (Staphylococcus aureus, Escherichia coli and Bacteroides fragilis), which characteristically dominate the colonization of perianal fistula tracts. Microspheres containing > 3 mol% silver or metronidazole resulted in strong bacterial inhibition/kill against B. fragilis; the presence of one sphere containing > 3 mol% silver had a potent inhibitory effect against all the microbes studied. Microspheres became rapidly integrated with host tissue following subcutaneous implantation into a rodent wound model.ConclusionsThe study demonstrates a novel scaffold for guided tissue regeneration providing local release of antimicrobial agents sufficient to counter bacterial colonization and warrants further investigation.

The First Convention of the Asian Psychological Association (APsyA) was held in Bali from 18-20th August 2006. This historic event marked the founding of the APsyA which is the first association in the Asian region with an individual membership spanning the whole field of psychology. The Conference was organized under the presidency of Sarlito Sarwono and was supported institutionally by the Faculty of Psychology at the University of Indonesia, Tarumanagara University, the Catholic University of Indonesia, the Indonesian Police Force, the International Council of Psychologists, Division 52 (International Psychology) of the American Psychological Association and the International Association of Applied Psychology. The Conference attracted over 120 participants from 17 countries; its Scientific Program covered matters such as indigenous Asian psychology, the contributions of psychology towards national development, and special issues in Asia. The principal symposium of the Conference dealt with terrorism and covered research into the psychology of terrorists, the process by which people become terrorists, and the rehabilitation of terrorists.

The Second Middle East and North Africa Regional Conference of Psychology was held in Amman from 27 April – 1 May 2007 under the Royal Patronage of Her Majesty Queen Rania Al‐Abdullah and the auspices of the International Union of Psychological Science, the International Association of Applied Psychology, and the International Association of Cross‐Cultural Psychology. It was hosted by the Jordanian Psychological Association whose President was Dr. Asaad Zuby. The President of the Conference and the Local Organizing Committee was Dr. Adnan Farah, the Chair of the Scientific Program Committee was Dr. Mohammad Rimawi, and the Chair of the Regional Advisory Committee was Dr. Marwan Dwairy. The Conference succeeded in attracting participants from 28 countries, including 15 from the Middle East and North Africa region. The Scientific Program explored ways and means to promote the role of psychology in meeting life challenges at regional and international levels. The Conference concluded with the signing of a fo...

Fabrication of calcium phosphate microtubes is performed utilizing a simple dissolution-reprecipitation mechanism, to form amorphous microtubes with sizes of the order of 10 to 20 mu m. Raman microspectroscopy gives more understanding of the degradation and formation mechanism.

Brushite cement is more soluble than apatitic cement under physiological conditions. Thus, brushite cement may be resorbable in vivo when used as a bone substitute material. Our group has previously reported the formation of brushite cement from orthophosphoric acid and several calcium phosphates such as β-tricalcium phosphate or nanocrystalline hydroxyapatite. In this study, polyphosphoric acid was investigated as a calcium phosphate cement component. We found that brushite cement was not formed when polyphosphoric acid was mixed with β-tricalcium phosphate but instead monocalcium phosphate monohydrate (MCPM) was formed. Although stronger in compression when tested dry, MCPM is readily soluble under physiological conditions and cement loses structural integrity within hours of aging in water. However, by varying the solid component phases, we have discovered a new route to the formation of brushite cement. The mixture of polyphosphoric acid, water, and tetracalcium phosphate yielded cement composed predominantly of brushite. The mechanical performance, microstructure, and setting time of this cement appeared to be dependent on the composition of the set cement, which in turn was determined by the composition of cement reactants in the cement slurry.

Purpose: The aim of this study was to evaluate the effect of water storage (24 hours and 1 year) on the tensile bond strength between the IPS Empress 2 ceramic and Variolink II resin cement under different superficial treatments. Materials and Methods: One hundred and eighty disks with diameters of 5.3 mm at the top and 7.0 mm at the bottom, and a thickness of 2.5 mm were made, embedded in resin, and randomly divided into six groups: Groups 1 and 4 = 10% hydrofluoric acid for 20 seconds; Groups 2 and 5 = sandblasting for 5 seconds with 50 µm aluminum oxide; and Groups 3 and 6 = sandblasting for 5 seconds with 100 µm aluminum oxide. Silane was applied on the treated ceramic surfaces, and the disks were bonded into pairs with adhesive resin cement. The samples of Groups 1 to 3 were stored in distilled water at 37 ◦ C for 24 hours, and Groups 4 to 6 were stored for 1 year. The samples were subjected to a tensile strength test in an Instron universal testing machine at a crosshead speed of 1.0 mm/min, until failure. The data were submitted to analysis of variance and Tukey’s test (5%). Results: The means of the tensile bond strength of Groups 1, 2, and 3 (15.54 ± 4.53, 10.60 ± 3.32, and 7.87 ± 2.26 MPa) for 24-hour storage time were significantly higher than those observed for the 1-year storage (Groups 4, 5, and 6: 10.10 ± 3.17, 6.34 ± 1.06, and 2.60 ± 0.41 MPa). The surface treatments with 10% hydrofluoric acid (15.54 ± 4.53 and 10.10 ± 3.17 MPa) showed statistically higher tensile bond strengths compared with sandblasting with 50 µm (10.60 ± 3.32 and 6.34 ± 1.06 MPa) and 100 µm (7.87 ± 2.26 and 2.60 ± 0.41 MPa) aluminum oxide for the storage time 24 hours and 1 year. Conclusions: Storage time significantly decreased the tensile bond strength for both ceramic surface treatments. The application of 10% hydrofluoric acid resulted in stronger tensile bond strength values than those achieved with aluminum oxide. J Prosthodont 2007;16:192-199. Copyright C � 2007 by The American College of Prosthodontists.

The Asian Applied Psychology International‐Regional Conference (AAPI‐RC) was held in Bangkok from 14–16th November 2005 under the auspices of the International Association of Applied Psychology (IAAP), the International Union of Psychological Science (IUPsyS), and the International Association for Cross‐Cultural Psychology (IACCP). The Conference was organized by Thammasat University and the Thai Psychological Association under the Conference Presidency of Ubolwanna Pavakanun. The Conference attracted a large number of Thai psychologists and students as well as a wide range of participants from 24 other countries, most from Thailand's near and far neighbours but others also from Europe and North America. Apart from the merits of its Scientific Program, the Conference had two important outcomes. One was to pave the way for the formation of a National Committee that will enable Thailand to become a member of the International Union of Psychological Science. The other was to facilitate the first Convention o...