Three-percent sucrose acts as a thermostabilizer for cell-adapted foot-and-mouth disease virus without any negative effect on viral growth.

AIMS: As cell-adapted foot-and-mouth disease virus (FMDV) with H56R mutation in VP3 has reduced thermostability, this study aimed to investigate the effect of thermostabilizers on cell-adapted FMDV for vaccine production. METHODS AND RESULTS: We examined the effect of 3% sucrose, 10% (or 25%) glycerol or 10% FBS on cell-adapted FMDV O/SKR/JC/2014, containing H56R mutation in VP3, as vaccine seed virus at -80, 4, 25 or 37°C for 2, 4 or 7 days. The stabilizing effect of 3% sucrose on O/SKR/JC/2014 was observed at 25, 37°C, and after repeated freeze-thaw cycles. Additionally, we tested the effect of 3% sucrose on the growth of FMDV or cells and did not observe any decrease in either viral growth or cell viability. CONCLUSIONS: Our study showed the protective effect of 3% sucrose on FMDV infectivity at various temperatures; this virus stock in 3% sucrose could be used for infecting cells without the removal of sucrose. SIGNIFICANCE AND IMPACT OF THE STUDY: We suggest that 3% sucrose-containing medium could be beneficial for the stable storage and transport of cell-adapted FMDV.

Oral health of Hong Kong children: a historical and epidemiological perspective.

OBJECTIVE: To provide a historical and epidemiological overview of the oral health of Hong Kong children. METHODS: Literature published before 2014 related to the oral health of Hong Kong children, supplemented with information accessed from government-archived oral health reports, was sourced using electronic databases and hand searches. Dental caries experience, periodontal health, enamel defects, and malocclusion of Hong Kong children were reviewed. RESULTS: A decline in the prevalence and extent of dental caries was observed among Hong Kong schoolchildren and adolescents after the 1960s. Among preschool children, however, dental caries remains common and the extent appears to have increased. The periodontal health of Hong Kong children remains unsatisfactory. Recently, enamel defects/dental fluorosis have considerably reduced. Information about malocclusion in Hong Kong children is limited. CONCLUSIONS: Since the 1960s, following public health policies, health promotion activities, and the introduction of a School Dental Care Service, improvements in the oral health of schoolchildren are evident. Nonetheless, the oral health of preschool children remains a concern. Policies and practices to improve the oral health of preschool children in Hong Kong are required.

Desipramine inhibits salivary Ca(2+) signaling and aquaporin translocation.

OBJECTIVE: Desipramine is a tricyclic antidepressant with a negative side effect of dry mouth. The Na(+) /H(+) exchanger was suggested to be a target of desipramine in salivary gland cells. However, it is unclear whether desipramine has other targets in the salivary secretion pathway. Here, we studied the effect of desipramine on salivary Ca(2+) signaling. MATERIALS AND METHODS: Cytosolic free Ca(2+) concentration ([Ca(2+) ]i ) was determined with the fluorescent Ca(2+) indicator fura-2/AM. Aquaporin translocation was analyzed by Western blotting and immunocytochemistry of confocal microscopy. RESULTS: Desipramine inhibited the carbachol- and histamine-mediated increase in cytosolic Ca(2+) ([Ca(2+) ]i ) in a concentration-dependent manner. However, desipramine did not affect increases in [Ca(2+) ]i mediated by extracellular ATP, sphingosine-1-phosphate, or thapsigargin. The adrenergic receptor blockers prazosin and propranolol did not reverse the desipramine-mediated inhibition of carbachol- and histamine-induced increases in [Ca(2+) ]i . We also found that desipramine inhibits the increase in membrane aquaporin-5 level triggered by carbachol and histamine treatments. CONCLUSIONS: These results imply that desipramine blocks muscarinic and histamine receptor-mediated Ca(2+) signaling and the subsequent translocation of aquaporin-5 in human salivary gland cells, suggesting a novel mechanism for the xerogenic effects of desipramine.

Barriers to providing oral health care to pre-school children-differences between paediatric dentists' and general dental practitioners' beliefs.

BACKGROUND: The unmet dental needs of pre-school children indicate there are barriers in 'accessing' appropriate oral health care and this warrants consideration of care providers' beliefs. OBJECTIVE: To explore the beliefs and attitudes of dentists in Hong Kong towards providing oral health care to pre-school children; and to determine difference in attitudes between general dental practitioners (GDPs) and paediatric dentists (PDs). METHODS: A random sample of 476 GDPs (-25% of all registered dentists) and all registered PDs (28) were invited to participate in the study. Both groups were asked to complete the Barriers to Childhood Caries Treatment (BaCCT) questionnaire: a 29-item measure considering child, parent, dentist and health care system factors. Differences in attitudes of GDPs and PDs were examined in bivariate and regression analyses. RESULTS: The overall response rate of the study was 61.5% (310/504). There were significant differences in overall BaCCT scores and across all domains between GDPs and PDs (p < 0.05). Furthermore, variations across many aspects (as described at an item level) were apparent. Regression analyses confirmed differences in BaCCT between GDPs and PDs, controlling for practice and other factors. CONCLUSIONS: Differences exist between GDPs' and PDs' perceptions of barriers to care for early childhood caries. This has implications for how to address 'access' issues with likely implications on how to overcome barriers to care for pre-school children.

Influence of dietary fibre on nutrient digestibility and energy utilisation in growing pigs fed diets varying in soluble and insoluble fibres from co-products.

The co-products from the industry are used to reduce costs in pig diets. However, the co-products used in pig diets are limited because of a high fibre content which is not digested by endogenous enzymes and is resistant to degradation in the small and large intestines. The aim of this study was to investigate digestibility of nutrients and energy, and energy utilisation in pigs fed diets with various soluble and insoluble dietary fibre (DF) from co-products. The experiment was performed as a 4 × 4 Latin square design (four diets and four periods) using four growing pigs (66.2 ±â€¯7.8 kg) surgically fitted with a T-cannula in the end of the small intestine. The pigs were fed four experimental diets: low-fibre control (LF), high-fibre control (HF), high-soluble fibre (HFS) and high-insoluble fibre (HFI) diets. The apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of ash, organic matter, CP, fat, carbohydrates, starch and non-starch polysaccharides (NSP) divided into cellulose and soluble and insoluble non-cellulosic polysaccharide residues were measured using chromic oxide as marker. The recovery of total solid materials, organic matter and total carbohydrates in ileal digesta in pigs fed the HF and HFS diets was higher than in pigs fed LF and HFI, whereas recovery of organic matter and total carbohydrates in faecal materials in the HFS diet was lowest (P < 0.05). AID of organic matter, total carbohydrates and starch was lowest for HFS diet (P < 0.05). ATTD of organic matter and CP was higher for LF diet compared with other diets (P < 0.05), whereas total NSP, cellulose and non-cellulosic polysaccharides residues were highest for HFS diet (P < 0.05). Lactic acid in ileal digesta was influenced by dietary composition (P < 0.05) whereas neither type nor level of DF affected short chain fatty acids. The digestible energy, metabolisable energy, net energy and retained energy intake were similar among diets without influence of DF inclusion (P > 0.05). The metabolisable energy:digestible energy ratio was lower when feeding the HFS diet because of a higher fermentative methane loss. Faecal nitrogen and carbon were positively correlated with DM intake and insoluble DF in the diets (P < 0.05), but nitrogen and carbon (% of intake) were similar among diets. The present findings suggest that high-DF co-products can be used as ingredients of pig diets when features of DF are considered.

Prenatal Substance Use Disorders and Dental Caries in Children.

Substance use is common in women of reproductive age, but limited data exist on the dental health of their children, including risk of caries. We conducted a longitudinal cohort study of 790,758 infants born between 2006 and 2016 in Quebec, Canada. We identified women with substance use disorders before or during pregnancy. The main outcome measure was hospitalization for dental caries in offspring up to 12 y after birth. We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for the association of maternal substance use with pediatric dental caries, adjusted for potential confounders. Children exposed to maternal substance use had a higher incidence of hospitalization for dental caries than unexposed children (105.2 vs. 27.0 per 10,000 person-years). Maternal substance use was associated with 1.96 times the risk of childhood dental caries (95% CI, 1.80-2.14), including a greater risk of caries of enamel, dentin, or cementum (HR, 2.00; 95% CI, 1.82-2.19) and dental pulp (HR, 2.36; 95% CI, 2.07-2.70), relative to no substance use. Associations were elevated for alcohol (HR, 2.31; 95% CI, 2.03-2.64) but were also present for cocaine, cannabis, opioids, and other substances. Substance use during pregnancy was more strongly associated with dental caries hospitalization than prepregnancy substance use. Associations were stronger in early childhood. Maternal substance use is associated with the future risk of dental caries hospitalization in children. Targeting substance use early in the lives of women may contribute to dental caries prevention in offspring.

Transoral endoscopic-assisted management of subcondylar fractures in 17 patients: an alternative to open reduction with rigid internal fixation and closed reduction with maxillomandibular fixation.

The authors evaluate the results of transoral endoscopic-assisted open reduction and miniplate fixation of subcondylar fractures. Seventeen patients were treated from August 2005 to April 2007. Inclusion criteria were: adult patients, inability to achieve adequate occlusion with closed reduction, dislocation of the condylar fragment between 10 and 45 degrees , and 2-mm inter-fragment overlapping. Regular panoramic radiographs were taken postoperatively. Transbuccal incisions were used to place the screws for fixation in 15 patients. Pure intraoral access and angulated drills and screwdrivers were used in 2 patients. The condyle was placed into the condylar fossa in all cases. No damage to the facial nerve was observed. No visible scars were present. Mean surgical time was 80.36 minutes. Transitory hyposthesia was observed in 3 cases. Adequate reduction and consolidation of the fracture was achieved in 16 patients. No condylar reabsortion was present at the end of the follow-up period. The authors consider that transoral endoscopic-assisted open reduction constitutes a valid alternative to a transcutaneous approach for the reduction and fixation of subcondylar fractures in selected cases. It provides the benefits of open reduction and internal fixation without the potential complications. Advice is given on how to achieve adequate reduction and stability of the proximal fragment.

Are biopolymers potential deodourising agents in wound management?

OBJECTIVE: To investigate the odour-adsorbing properties of biopolymers, with a view to using the findings to develop a novel dressing with odour-adsorbing properties. METHOD: The odour-adsorbing properties of a selection of biopolymers (aloe vera, tea tree oil, neem oil and manuka honey) and three commercially available dressings containing activated charcoal cloth (ACC) were quantitatively assessed using laboratory test equipment. An aloe vera-containing composite dressing, designed and developed by the authors, was also compared with the ACC dressings. RESULTS: Aloe vera was the most adsorbent of the biopolymers and a 40% dilution had comparable values to those of the ACC dressings. Furthermore, values for the novel composite dressing were similar to those of the ACC dressings. CONCLUSION: The novel composite dressing may be a potential alternative to ACC dressings, and has the added advantages of having antimicrobial properties as well as the ability to promote a moist wound environment. However, more research is needed.

Properties of lightweight aggregate concrete prepared with PVC granules derived from scraped PVC pipes.

This paper aims to investigate the fresh and hardened properties of lightweight aggregate concretes that are prepared with the use of recycled plastic waste sourced from scraped PVC pipes to replace river sand as fine aggregates. A number of laboratory prepared concrete mixes were tested, in which river sand was partially replaced by PVC plastic waste granules in percentages of 0%, 5%, 15%, 30% and 45% by volume. Two major findings are identified. The positive side shows that the concrete prepared with a partial replacement by PVC was lighter (lower density), was more ductile (greater Poisson's ratios and reduced modulus of elasticity), and had lower drying shrinkage and higher resistance to chloride ion penetration. The negative side reveals that the workability, compressive strength and tensile splitting strength of the concretes were reduced. The results gathered would form a part of useful information for recycling PVC plastic waste in lightweight concrete mixes.

An outbreak of avian mycobacteriosis caused by Mycobacterium intracellulare in little blue penguins (Eudyptula minor).

Mycobacterium intracellulare (MIT) was diagnosed postmortem by culture and supporting histopathology in seven birds from a flock of little blue penguins (Eudyptula minor) at the Henry Doorly Zoo (HDZ). These birds represented 20% of the deaths in the population over a 4 yr period. Clinical signs in affected birds included severe respiratory distress characterized by open-mouth breathing with chronic debilitation. On exam, plaques were noted in the larynx, trachea, and soft tissue of the caudal oropharynx. Index cases were identified on necropsy in two birds on loan to another institution in 2003. Following a case confirmed antemortem at the HDZ, a three-drug protocol of rifampin (15 mg/kg p.o. s.i.d.), ethambutol (15 mg/kg p.o. s.i.d.), and clarithromycin (10 mg/kg p.o. s.i.d.) was started on this bird in 2004 and extended to the entire flock in 2005. Gastric wash, fecal samples, and throat plaques were obtained antemortem on five birds within the flock, selected because of the presence of oral plaques, and tested by culture followed by a polymerase chain reaction assay. MIT was detected in gastric washes from four birds and in throat plaques from all five. Three more birds died during treatment. After the seventh bird died, antimicrobial susceptibility testing performed in July 2007 indicated that the MIT was now resistant to most antibiotics tested, including rifampin and ethambutol. The treatment regimen was changed to minocycline (10 mg/kg p.o. b.i.d.) and clarithromycin (10 mg/kg p.o. s.i.d.). Oral plaques were not seen on monthly rechecks of the flock through November 2008. The proposed mechanism of transmission is exposure to wild birds but the source has not been determined. These cases of avian mycobacteriosis caused by MIT are the first known cases reported in little blue penguins.

NAMPT Is an Essential Regulator of RA-Mediated Periodontal Inflammation.

Recent studies have indicated a potential correlation between rheumatoid arthritis (RA) and periodontal inflammation. We undertook this study to verify whether RA mediates periodontitis-like phenotypes in experimental mouse models of RA and to explore the role of nicotinamide phosphoribosyltransferase (NAMPT) in periodontal inflammation during RA pathogenesis. Periodontal inflammation and alveolar bone loss have been reported in mice with collagen-induced arthritis (CIA) and in genetically modified tumor necrosis factor-α (TNF-α) transgenic (TG) mouse models. Among the adipokines examined in our study, NAMPT expression was markedly upregulated in the periodontal ligament (PDL) tissues in RA mouse models and in human PDL cells stimulated by the proinflammatory cytokines, interleukin (IL) 1ß and TNF-α. When NAMPT was overexpressed with the Nampt-synthesizing adenovirus vector (Ad- Nampt), the PDL cells exhibited an increased expression of cytokines (IL6), chemokines (IL8 and chemokine [C-C motif] ligand 5 [CCL5]), inflammatory mediators (cyclooxygenase 2 [COX-2]), and matrix-degrading enzymes (matrix metalloproteinase [MMP] 1 and MMP3). Inhibition of NAMPT by the intracellular NAMPT (iNAMPT) inhibitor, FK866, or by the sirtuin inhibitor, nicotinamide, in PDL cells led to inhibition of the IL1ß or Ad- Nampt-induced upregulation of catabolic factors, whereas treatment with recombinant NAMPT protein or blockade of extracellular NAMPT (eNAMPT) with blocking antibody did not. Moreover, NAMPT inhibition by the intraperitoneal or intragingival injection of FK866 in CIA mice inhibited periodontal tissue damage, under conditions of RA. Thus, our results verified the co-occurrence of RA and periodontal inflammation using experimental mouse models of RA, suggesting that iNAMPT in PDL cells plays a pivotal role in the pathogenesis of RA-mediated periodontal inflammation by regulating the expression levels of catabolic genes, such as IL6, IL8, CCL5, COX-2, MMP1, and MMP3.

Direct Gingival Fibroblast/Osteoblast Transdifferentiation via Epigenetics.

Alveolar bone resorption caused by trauma or periodontal diseases has represented a challenge for both dental clinicians and researchers. In this study, we evaluate the osteogenic potential of human gingival fibroblasts (HGFs) through a direct transdifferentiation from HGFs to functional osteoblasts via epigenetic modification and osteogenic signaling with bone morphogenetic protein 2 (BMP2) in vitro and in vivo. HGF treatment with 5-aza-2'-deoxycytidine (5-aza-dC) induced demethylation in the hypermethylated CpG islands of the osteogenic lineage marker genes RUNX2 and ALP, and subsequent BMP2 treatment successfully drove the fibroblasts to the osteoblasts' lineage. Cell morphological changes viewed under microscopy and alkaline phosphatase (ALP) and alizarin red S (ARS) staining confirmed the osteoblastic change mediated by epigenetic modification as did real-time polymerase chain reaction (PCR), methylation-specific PCR (MSP), and chromatin immunoprecipitation (ChIP) assay, which demonstrated the altered methylation patterns in the RUNX2 and ALP promoter regions and their effect on gene expression. Furthermore, micro-computed tomography (CT) analysis of in vivo mouse cell transplantation experiments showed high-density signal in the epigenetically modified HGF group; in addition, a significant amount of bone formation was observed in the transplanted material using hematoxylin and eosin (H&E) staining as well. Collectively, our results indicate that epigenetic modification permits the direct programming of HGFs into functional osteoblasts, suggesting that this approach might open a novel therapeutic avenue in alveolar bone regeneration.

RhoA-JNK Regulates the E-Cadherin Junctions of Human Gingival Epithelial Cells.

The junctional epithelium (JE) is unique with regard to its wide intercellular spaces and sparsely developed intercellular junctions. Thus, knowledge of the molecular mechanisms that regulate the formation of the intercellular junctions of the junctional epithelium may be essential to understand the pathophysiology of the JE. HOK-16B cells, a normal human gingival epithelial cell line, were used to identify the molecules involved in the regulation of the formation of intercellular E-cadherin junctions between human gingival epithelial cells. Activation of c-Jun N-terminal kinase (JNK) disrupted the intercellular junctions through the dissociation of E-cadherin. The role of JNK in the formation of these E-cadherin junctions was further confirmed by demonstrating that JNK inhibition induced the formation of intercellular E-cadherin junctions. The upstream signaling of JNK was also examined. Activation of the small GTPase RhoA disrupted the formation of E-cadherin junctions between HOK-16B cells, which was accompanied by JNK activation. Disruption of these intercellular junctions upon RhoA activation was prevented when JNK activity was inhibited. In contrast, RhoA inactivation led to HOK-16B cell aggregation and the formation of intercellular junctions, even under conditions in which the cellular junctions were naturally disrupted by growth on a strongly adhesive surface. Furthermore, the JE of mouse molars had high JNK activity associated with low E-cadherin expression, which was reversed in the other gingival epithelia, including the sulcular epithelium. Interestingly, JNK activity was increased in cells grown on a solid surface, where cells showed higher RhoA activity than those grown on soft surfaces. Together, these results indicate that the decreased formation of intercellular E-cadherin junctions within the JE may be coupled to high JNK activity, which is activated by the upregulation of RhoA on solid tooth surfaces.

Effect of preoperative autologous blood donation on patients undergoing bimaxillary orthognathic surgery: a retrospective analysis.

The efficacy of preoperative autologous blood donation (PABD) was evaluated according to preoperative haemoglobin (Hb) values. The records of 295 patients who underwent bimaxillary orthognathic surgery between July 2007 and August 2008 were reviewed. The records for autologous blood donation, intraoperative transfusion, and related laboratory studies were also evaluated. The transfusion trigger used during this period was Hb < 10 g/dl. A total of 189 patients (64.1%) made a PABD and 106 patients (35.9%) did not. The incidence of allogeneic blood transfusion was significantly lower in the PABD group than in the no PABD group (15.9% vs. 29.2%, P = 0.007). This difference was greater in patients with a preoperative Hb < 14 g/dl (20.3% vs. 62.5%, P < 0.0001), and no difference was found in patients with Hb ≥ 14 g/dl (13.3% vs. 14.9%, P = 0.83). PABD reduced the incidence of allogeneic blood transfusion in patients undergoing bimaxillary orthognathic surgery, particularly in patients with a preoperative Hb < 14 g/dl. PABD could be used to reduce the frequency of intraoperative allogeneic blood transfusion in these patients.

Varying Ti-6Al-4V surface roughness induces different early morphologic and molecular responses in MG63 osteoblast-like cells.

Osteoblast response to Ti implants depends not only on the chemistry of the implant but also on the physical properties of the implant surface, such as microtopography and roughness. This study was undertaken to examine early changes in cell morphology and gene expression during the early phase of osteoblast interaction with titanium alloy (Ti-6Al-4V) surfaces of two different roughnesses. MG63 osteoblast-like cells were cultured for 2, 6, 24, and 72 h on smooth (Ra=0.18+/-0.03 microm) and rough (Ra=2.95+/-0.23 microm) Ti-6Al-4V surfaces. Changes in cell proliferation were assessed by measuring cell number after 72 h in culture. Morphological characteristics were observed by scanning electron microscopy after 2, 6, and 24 h of culture. Changes in gene expression for extracellular signal-regulated kinase 2 (Erk2), type I collagen (alpha2[I] collagen), phospholipase C-gamma2 (Plc-gamma2), and beta-actin were measured by RT-PCR after 6 and 24 h in culture. Cell number was significantly higher on the smooth surface. In scanning electron micrographs, cells on smooth Ti-6Al-4V were spherical and raised up from the surface after 2 h in culture. In contrast, cells on the rough surface adopted an irregular, elongated shape that spanned across pits in the surface. At 24 h, cells on the smooth surface had flattened, become elongate, and covered the surface. In contrast, cells on the rough surface appeared more differentiated in shape and the margins of the cells were irregular, with many processes extending out, following the contour of the surface. Of the genes examined, only Erk2 and beta-actin showed a change in expression with surface roughness. Both genes were upregulated (p<0.05) on the rough surface at 6 h. These results indicate that Ti-6Al-4V surface roughness affects osteoblast proliferation, morphology, and gene expression, and that these effects can be measured after periods as short as 2-6 h.

Effects of the 2-amino-3-hydroxy-5-methyl-4-isoxazole-proprionic acid/kainate antagonist LY293558 on spontaneous and evoked postoperative pain.

BACKGROUND: Previous studies suggest that 2-amino-3-hydroxy-5-methyl-4-isoxazole-proprionic acid (AMPA)/kainate antagonists reduce experimentally induced pain. There have been no studies of AMPA/kainate antagonists in clinical pain. METHODS: Analgesic efficacy of intravenous LY293558 (0.4 or 1.2 mg/kg) was compared with that of intravenous ketorolac tromethamine (INN, ketorolac; 30 mg) and placebo in a randomized, double-blind, parallel-group study after oral surgery (n = 70). Study drugs were administered at the onset of moderate pain; pain intensity and relief were measured for 240 minutes. RESULTS: High-dose LY293558 and ketorolac tromethamine were superior to placebo (P < .05) for pain evoked by mouth opening and one of several measures of spontaneous pain: SPID240 +/- SEM for pain evoked by mouth opening was highest for ketorolac tromethamine (151 +/- 58), intermediate for high-dose LY293558 (-45 +/- 35), and least for low-dose LY293558 (-151 +/- 39) and placebo (-162 +/- 50). High-dose LY293558 was superior to placebo at individual time points (45 to 240 minutes) for pain evoked by mouth opening but not for spontaneous pain. The spontaneous summed pain intensity difference over 240 minutes (SPID240 +/- SEM) was highest for ketorolac tromethamine (303 +/- 84), intermediate for high-dose LY293558 (-51 +/- 40) and low-dose LY293558 (-96 +/- 45), and least for placebo (-180 +/- 24). LY293558 was well tolerated, with dose-dependent and reversible side effects including hazy vision in 20% of patients and sedation in 15%. CONCLUSIONS: This is the first evidence that an AMPA/kainate antagonist reduces clinical pain. Tests of evoked pain may be more sensitive to certain analgesics than those of spontaneous pain. The evaluation of evoked pain as an outcome measure in analgesic trials may identify potentially useful compounds otherwise missed if only spontaneous pain is evaluated.

Cyclic 3'-5'-adenosine monophosphate binds to annexin I and regulates calcium-dependent membrane aggregation and ion channel activity.

The annexin (Anx) gene family comprises a set of calcium-dependent membrane binding proteins, which have been implicated in a wide variety of cellular processes including membrane fusion and calcium channel activity. We report here that cAMP activates Ca(2+)-dependent aggregation of both phosphatidylserine (PS) liposomes and bovine chromaffin granules driven by [des 1-12]annexin I (lipocortin I, Anx1). The mechanism of cAMP action involves an increase in AnxI-dependent cooperativity on the rate of such a reaction without affecting the corresponding k1/2 values. Cyclic AMP causes the values of the Hill coefficient (nH) for AnxI to change from 3 to 6 in both PS liposomes and chromaffin granules. By contrast, ATP inhibits the rate of aggregation activity without affecting the cooperativity or the extent of aggregation process. We were also able to photolabel Anx1 specifically with an 8-azido analogue of cAMP by a calcium-independent process. Such a process is saturable, yielding a Kd = 0.8 microM by Scatchard analysis. Specific displacement occurs in the presence of cAMP and ATP. Finally, we found that cAMP alters the conductance of calcium channels formed by AnxI in planar lipid bilayers. We interpret these data to indicate that AnxI binds both calcium and cAMP independently, and that both actions have functional consequences. This is the first report of a nucleotide binding function for a member of the annexin gene family.

Immobilization of poly(ethylene glycol) or its sulfonate onto polymer surfaces by ozone oxidation.

A novel surface modification method has been developed to improve biocompatibility of polymeric biomaterials. This approach involves ozonation and then followed by graft polymerization with acrylates containing PEG, sulfonated PEG or by coupling of PEG derivatives. All the reactions were confirmed by ATR FT-IR and ESCA. The degree of ozonation measured by the iodide method was dependent on the ozone permeability of the polymers used. Surface hydrophilicity was investigated by measuring the contact angles. Ozonation itself yielded a slight increase in hydrophilicity and a decrease in platelet adhesion, but PEG immobilization showed a significant effect on surface hydrophilicity and platelet adhesion to confirm well-known PEG's passivity which minimize the adhesion of blood components on polymer surfaces. Both graft polymerization and coupling were effective for PU. In contrast, only grafting gave enough yields for PMMA and silicone. Platelet adhesion results demonstrated that all PEG modified surfaces adsorbed lower platelet adhesion than untreated or ozonated ones. Polymers coupled with sulfonated PEG exhibited the lowest platelet adhesion when compared with control and PEG coupled ones by virtue of the synergistic effect of non-adhesive PEG and negatively charged SO3 groups. This PEG or sulfonated PEG immobilization technology using ozonation is relatively simple for introducing uniform surface modification and therefore very useful for practical application of blood contacting medical devices.

The effect of surgical handwashing routines on the microbial counts of operating room nurses.

Many factors may affect the efficiency of handwashing techniques. This study examined two interdependent factors: the time taken to wash the hands and the type of antiseptic solution used. A 3-minute initial scrub and 30-second consecutive scrub regimen was compared with a current standard regimen of a 5-minute initial scrub and a 3-minute consecutive scrub. Chlorhexidine gluconate 4% and povidone-iodine 7.5% were the antiseptics used in the two regimens. The sample (n = 34) was drawn from nurses employed in the operating room suite of a 950-bed hospital. Chlorhexidine gluconate was found to be responsible for lower numbers of colony-forming units of bacteria than povidone-iodine. The duration of the scrub had no significant effect on the numbers of bacteria when povidone-iodine was used. The optimal regimen was found to be the 5-minute initial and 3-minute consecutive scrubs with chlorhexidine gluconate.

An evaluation of five protocols for surgical handwashing in relation to skin condition and microbial counts.

Five protocols for surgical handwashing (scrubbing) were evaluated for their efficiency of removal of micro-organisms and their drying effect on the skin. The scrubbing protocols tested were: (1) an initial scrub of 5 min and consecutive scrubs of 3.5 min with chlorhexidine gluconate 4% (CHG-5); (2) an initial scrub of 3 min and consecutive scrubs of 2.5 min with chlorhexidine gluconate 4% (CHG-3); (3) an initial scrub of 3 min and consecutive scrubs of 2.5 min with povidone iodine 5% and triclosan 1% (PI-3); (4) an initial scrub of 2 min with chlorhexidine gluconate 4% followed by a 30 s application of isopropanol 70% and chlorhexidine gluconate 0.5%, and a 30 s application of isopropanol 70% and chlorhexidine gluconate 0.5% for consecutive scrubs (IPA); and (5) an initial scrub of 2 min with chlorhexidine gluconate 4% followed by a 30 s application of ethanol 70% and chlorhexidine gluconate 0.5%, and a 30 s application of ethanol 70% and chlorhexidine gluconate 0.5% for consecutive scrubs (EA). A convenience sample of 23 operating theatre nurses completed each scrub protocol for one week in a randomized order. A week of normal work activities intervened between each protocol. Subjects were assessed before commencing and after completing the week of each protocol to determine changes in the microbial counts and skin condition of the hands. Specimens for microbial analysis were collected before, immediately after and 2 h after an initial scrub, and 2 h after a consecutive scrub. The CHG-5, CHG-3 and PI-3 protocols, which used detergent-based antiseptics only, were compared with protocols incorporating an alcohol-based antiseptic (IPA and EA). The protocols incorporating alcohol-based antiseptics and the CHG-5 protocol were generally associated with the lowest post-scrub numbers of colony forming units (cfu). No difference between the CHG-5 protocol and the alcohol-based antiseptics was found at the beginning of the test week, but after exclusive use of the respective protocols for a week, the alcohol-based antiseptics were associated with significantly lower cfu numbers in two out of the three post-scrub samples (P = 0.003, P = 0.035). Although virtually no statistically significant differences in skin condition were found, many subjects reported the alcohol-based antiseptic protocols to be less drying on the skin. The findings of this study support the proposition that a scrub protocol using alcohol-based antiseptics is as effective and no more damaging to skin than more time-consuming, conventional methods using detergent-based antiseptics.