bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust Representation of Dry Cells in Single‐Layer MODFLOW Models
Authors: Painter Scott , Başağaoğlu Hakan , Liu Angang
Published: August 2008

Dewatered or “dry” grid cells in the USGS ground water modeling software MODFLOW may cause nonphysical artifacts, trigger convergence failures, or interfere with parameter estimation. These difficulties can be avoided in two dimensions by modifying the spatial differencing scheme and the iterative procedure used to resolve nonlinearities. Specifically, the spatial differencing scheme is modified to use the water level on the upstream side of a pair of adjacent cells to calculate the saturated thickness and hence intercell conductance for the pair. This makes it possible to explicitly constrain the water level in a cell to be at or above the cell bottom elevation without introducing nonphysical artifacts. Thus constrained, all initially active cells will remain active throughout the simulation. It was necessary to replace MODFLOW’s Picard iteration method with the Newton‐Raphson method to achieve convergence in demanding applications involving many dry cells. Tests using a MODFLOW variant based on the new method produced results nearly identical to conventional MODFLOW in situations where conventional MODFLOW converges. The new method is extremely robust and converged in scenarios where conventional MODFLOW failed to converge, such as when almost all cells dewatered. An example application to the Edwards Aquifer in south‐central Texas further demonstrates the utility of the new method.
An Assembly Model for Simulation of Large‐Scale Ground Water Flow and Transport
Authors: Huang Junqi , Christ John A. , Goltz Mark N.
Published: August 2008

When managing large‐scale ground water contamination problems, it is often necessary to model flow and transport using finely discretized domains—for instance (1) to simulate flow and transport near a contamination source area or in the area where a remediation technology is being implemented; (2) to account for small‐scale heterogeneities; (3) to represent ground water–surface water interactions; or (4) some combination of these scenarios. A model with a large domain and fine‐grid resolution will need extensive computing resources. In this work, a domain decomposition–based assembly model implemented in a parallel computing environment is developed, which will allow efficient simulation of large‐scale ground water flow and transport problems using domain‐wide grid refinement. The method employs common ground water flow (MODFLOW) and transport (RT3D) simulators, enabling the solution of almost all commonly encountered ground water flow and transport problems. The basic approach partitions a large model domain into any number of subdomains. Parallel processors are used to solve the model equations within each subdomain. Schwarz iteration is applied to match the flow solution at the subdomain boundaries. For the transport model, an extended numerical array is implemented to permit the exchange of dispersive and advective flux information across subdomain boundaries. The model is verified using a conventional single‐domain model. Model simulations demonstrate that the proposed model operated in a parallel computing environment can result in considerable savings in computer run times (between 50% and 80%) compared with conventional modeling approaches and may be used to simulate grid discretizations that were formerly intractable.
Bone anchored hearing aids: a preliminary assessment of the impact on outpatients and cost when rehabilitating hearing in chronic suppurative otitis media
Authors: Watson G.J. , Silva S. , Lawless T. , Harling J.L. , Sheehan P.Z.
Published: August 2008

Objectives:  To compare the difference in ENT and Audiology visits, treatments dispensed and potential savings pre‐ and post‐bone anchored hearing aid (BAHA) insertion in patients with chronic suppurative otitis media exacerbated by behind the ear hearing aids.

Design:  A retrospective pilot study.

Setting:  District General Hospital.

Participants:  All patients who had BAHA inserted from January 2001 to January 2006.

Parameters:  Age, gender, number of visits per month, treatments per month dispensed from the ENT and Audiology Departments and direct and limited indirect medical costs pre‐ and post‐BAHA insertion.

Results:  Twelve of 26 (46%) adult patients had BAHA inserted over the 5‐year period for CSOM. The male to female ratio was 1 : 3 with a median age of 61 (range 29–81). The number of visits and treatments dispensed per month in the ENT Department fell from a mean of 0.42–0.33 (P < 0.08) and 0.22–0.14 (P < 0.02) respectfully.

When the difference in medical cost was taken into account BAHA offered a potential saving of £627.80 per patient.

Conclusion:  Although the initial acquisition of surgical equipment and BAHA sound processors is expensive, there is a reduction in the number of treatments and visits required for patients with chronic suppurative otitis media after BAHA is inserted leading to a reduction in average costs.
An autonomous surgical robot for drilling a cochleostomy: preliminary porcine trial
Authors: Coulson C.J. , Taylor R.P. , Reid A.P. , Griffiths M.V. , Proops D.W. , Brett P.N.
Published: August 2008

Objective:  To produce an autonomous drilling robot capable of performing a bony cochleostomy whilst minimising the damage to the underlying cochlear endosteum.

Design:  In this laboratory based study, a robotic drill was designed to measure the changes in force and torque experienced by the tool point during the drilling process. This information is used to predict the point of breakthrough and stop the drill prior to damaging the underlying endosteal membrane.

Setting:  Aston University.

Participants:  Five porcine cochleas.

Main outcomes measures:  An assessment was made of whether a successful bony cochleostomy was performed, the integrity of endosteal membrane was then assessed.

Results:  The autonomous surgical robotic drill successfully performed a bony cochleostomy and stopped without damaging the endosteal membrane in all five cases.

Conclusions:  The autonomous surgical robotic drill can perform a cochleostomy whilst minimising the trauma to the endosteal membrane. The system allows information about the state of the drilling process to be derived using force and torque data from the tool point. This information can be used to effectively predict drill breakthrough and implement a control strategy to minimise drill penetration beyond the far surface.
Relative importance of diagnostic delays in different head and neck cancers
Authors: Teppo H. , Alho O.‐P.
Published: August 2008

Objectives: Clinical stage at the time of diagnosis is the most important determinant of prognosis in head and neck cancer. Previously, longer diagnostic delay has been shown to worsen prognosis in cancer of tongue, pharynx and larynx. The aim of this study was to evaluate the relative importance of patient and professional diagnostic delays in the prognosis of these head and neck cancers.

Design: Population‐based retrospective cohort study.

Setting: Oulu University Hospital (tertiary referral centre) district, Northern Finland.

Participants: Population‐based cohort of 221 patients with tongue, pharyngeal or laryngeal cancer diagnosed in 1986–1996.

Main outcome measures: Patient and professional diagnostic delays, overall survival.

Results: Delays were significantly longer in laryngeal cancer. Moreover, longer diagnostic delays worsened survival markedly only in laryngeal cancer. Cut‐off points at which the delays showed significant adverse impact in prognosis of laryngeal cancer were ≥3 months in patient delay and ≥6 months in professional delay. If mirror laryngoscopy was not performed at the initial visit, professional delay in laryngeal cancer turned out to be significantly longer.

Conclusions: Diagnostic delays are longer and have a more significant impact on survival in laryngeal cancer than in lingual or pharyngeal cancer. Thus, patients with symptoms suggestive of laryngeal process should always be examined properly at the initial visit in order to shorten the professional diagnostic delay in laryngeal cancer.
Re‐irradiation with concurrent chemotherapy in recurrent head and neck cancer: a decision analysis model based on a systematic review
Authors: Paleri V. , Kelly C.G.
Published: August 2008

Objectives:  Local recurrence is the major cause of treatment failure in head and neck cancer patients after radiation or combined therapy. If surgically unresectable, management involves supportive care or chemotherapy with palliative intent. Recent studies have assessed the role of re‐irradiating these patients with concurrent chemotherapy (CTReRT) and have reported improved local control. The aim of this study was to perform a decision analysis model comparing quality adjusted life years (QALYs) between patients undergoing CTReRT and best supportive care for radio‐recurrent head and neck squamous cancer.

Design:  Outcome data from recent reviews on the topic were used. A decision analysis model was generated. An expert panel arrived at a consensus to assign utility values for the various health state outcomes when CTReRT is administered for recurrent cancer, or in the setting of palliative care for these patients.

Main outcome measures:  Quality adjusted life years from the decision analysis model.

Results:  Patients who do not suffer a severe complication following CTReRT were assigned by the expert panel to have a utility value of 0.7, and those who suffered one, a utility value of 0.6. A value of 1.0 equates to perfect health and 0 to death. The utility value assigned in the setting of good palliation was 0.8, with 0.6 given when symptom control was less than optimal. The model showed superior QALYs for the CTReRT arm of approximately 5 weeks (20 weeks versus 15 weeks for palliation).

Conclusions:  Re‐irradiation with concurrent chemotherapy is a modality to be considered in select patients with recurrent head and neck cancer. These results should help to better inform both patients and clinicians when considering this treatment.
Mathematically Assessing the Consequences of Food Terrorism Scenarios
Authors: Liu Y. , Wein L.M.
Published: August 2008

ABSTRACT:  We derive mathematical expressions for the mean number of casualties resulting from a deliberate release of a biological or chemical agent into a food supply chain. Our analysis first computes the amount of contaminated food as a function of the network topology and vessel sizes in the food processing plant. A probabilistic analysis, in which each potential consumer of contaminated food has his own random purchase time, infectious dose, and incubation period, determines the number of people who consume enough tainted food to get infected or poisoned before the attack is detected and food consumption is halted. These simple formulas can be used by the U.S. government and the food industry to develop a rough‐cut prioritization of the threats from food terrorism, which would be a 1st step toward the allocation of appropriate prevention and mitigation resources.
Microstructure of Fat Globules in Whole Milk after Thermosonication Treatment
Authors: Bermúdez‐Aguirre D. , Mawson R. , Barbosa‐Cánovas G.V.
Published: August 2008

ABSTRACT:  The structure of fat globules in whole milk was studied after heat and thermosonication treatments to observe what happens during these processes at the microscopic level using scanning electron microscopy. Raw whole milk was thermosonicated in an ultrasonic processor—Hielscher® UP400S (400 W, 24 kHz, 120 μm amplitude), using a 22‐mm probe at 63 °C for 30 min. Heat treatment involved heating the milk at 63 °C for 30 min. Color and fat content were measured to correlate the images with analytical measurements. The results showed that the surface of the fat globule was completely roughened after thermosonication. Ultrasound waves were responsible for disintegrating the milk fat globule membrane (MFGM) by releasing the triacylglycerols. Furthermore, the overall structure of milk after sonication showed smaller fat globules (smaller than 1 μm) and a granular surface. This was due to the interaction between the disrupted MFGM and some casein micelles. Minor changes in the aspect of the globules between thermal and raw milks were detected. Color measurements showed higher L* values for sonicated samples. Sonicated milk was whiter (92.37 ± 0.20) and generally showed a better degree of luminosity and homogenization compared to thermal treated milk (88.25 ± 0.67) and raw milk (87.82 ± 0.18). Fat content analysis yielded a higher value after sonication (4.24%) compared to untreated raw milk (4.04%) because fat extraction is more efficient after sonication. The advantages of thermosonicated milk are that it can be pasteurized and homogenized in just 1 step, it can be produced with important cost savings, and it has better characteristics, making thermosonication a potential processing method for milk and most other dairy products.
Effect of Freezing Time on the Quality of Indian Mackerel (Rastrelliger kanagurta) during Frozen Storage
Authors: Lakshmisha I.P. , Ravishankar C.N. , Ninan G. , Mohan C.O. , Gopal T.K.S.
Published: August 2008

ABSTRACT:  The present study aims to find the effect of freezing methods on the quality of mackerel (Rastrelliger kanagurta) in commercial plate and air blast freezers during freezing and subsequent frozen storage (−18 °C). Total time for freezing was significantly different (P < 0.05) between the plate and air blast freezers (90 and 220 min, respectively). This difference in the freezing time could be attributed to the varied quality of the 2 samples. Upon freezing, the moisture content decreased in air blast frozen samples compared to plate freezer where protein content decreased in both the samples. Upon freezing and during frozen storage, lipid oxidation products (peroxide value, thiobarbutiric acid value, and free fatty acid value) and volatile bases (total volatile base nitrogen and trimethyl amine nitrogen) showed an increasing trend in both the samples with values slightly higher in air blast frozen samples compared to plate frozen samples. The total plate counts showed a significantly (P < 0.05) decreasing trend in both the samples. K value did not show any significant (P < 0.05) difference between the samples where as the histamine formation was significantly (P < 0.05) increased in air blast frozen samples compared to plate frozen samples. The taste and overall acceptability was significantly different (P < 0.05) in plate frozen samples compared to air blast frozen samples on 3rd month. Both samples were in acceptable condition up to 3 mo but the plate frozen samples quality was slightly better than the air blast frozen samples.
Resistance of Nutrient‐Deprived Listeria monocytogenes 10403S and a ΔsigB Mutant to Chemical Stresses in the Presence or Absence of Oxygen
Authors: Lungu B. , Ricke S.C. , Johnson M.G.
Published: August 2008

ABSTRACT:  Nutrient‐deprived Listeria monocytogenes have increased resistance to processing control measures. Heat‐stressed L. monocytogenes cells produce higher counts under anaerobic conditions and SigB reportedly contributes to the survival of environmentally stressed Gram‐positive bacteria. In this study, a wild type (wt) strain, L. monocytogenes 10403S, and a ΔsigB mutant, FSLA1‐254, were stressed by starvation in phosphate buffered saline coupled with exposure to chemicals with/without oxygen. In the absence of chemicals, the mutant survived starvation almost as well as the wt, suggesting that the starvation survival response (SSR) in L. monocytogenes was SigB‐independent. Conversely, in the presence of chemical stresses the SSR results differed depending on the chemical used. In the presence of sodium chloride (SC), both strains were able to express an SSR under aerobic conditions but not under anaerobic conditions. However, in the presence of sodium propionate (SP), the mutant yielded counts that were 2 log CFU/mL lower than the controls and their aerobic counterparts. In the presence of sodium lactate (SL), the mutant yielded counts that were approximately 3 log CFU/mL lower than the wt under anaerobic conditions. Thus, for the chemical stress produced by SC, the SSR appeared to be SigB‐independent. The SSR of L. monocytogenes appeared to be SigB‐dependent following exposure to SP or SL under anaerobic conditions. Following exposure to sodium diacetate or lauric acid, both strains were unable to express an SSR. No detectable CFUs were observed after 14 to 21 d under either aerobic or anaerobic incubation. Therefore, these 2 chemicals could be used in biocidal formulations against L. monocytogenes cells under aerobic or anaerobic conditions.
Antibacterial Compounds from Rose Bengal‐Sensitized Photooxidation of β‐Caryophyllene
Authors: Kim Y.S. , Park S.J. , Lee E.J. , Cerbo R.M. , Lee S.M. , Ryu C.H. , Kim G.S. , Kim J.O. , Ha Y.L.
Published: August 2008

ABSTRACT:  The bactericidal activity of β‐caryophyllene photooxidized in acetonitrile was examined for 5 Gram‐positive and 4 Gram‐negative foodborne bacteria. The β‐caryophyllene (5 × 10−3 M) was photooxidized in acetonitrile containing Rose Bengal (6.25 × 10−4 M) for 24 h under fluorescent light. The antimicrobial activities of samples were determined by the agar‐disc diffusion method. Active compounds from the photooxidized β‐caryophyllene were isolated by silica gel open‐column chromatography in conjunction with recyclic high‐performance liquid chromatography (HPLC), and were identified by infrared spectroscopy, mass spectrometry, and nuclear magnetic resonance spectroscopy. The antimicrobial activity of the photooxidized β‐caryophyllene was strongly enhanced against Streptococcus aureus and Vibrio parahaemolyticus, relative to that of β‐caryophyllene, but was weakly enhanced against other tested bacteria. The photooxidized β‐caryophyllene contained 3 active compounds specific for these 2 bacteria, and the compounds were identified as 5‐α‐hydroxycaryophylla‐4(12),8(13)‐diene, 5‐α‐hydroxycaryophylla‐3(4),8(13)‐diene, and 5‐β‐hydroxycaryophylla‐3(4),8(13)‐diene. The efficacies of these compounds were similar, but the efficacy of 5‐β‐hydroxycaryophylla‐3(4),8(13)‐diene was slightly higher than that of the other 2 compounds. The results suggest that the antibacterial activities of β‐caryophyllene for S. aureus and V. parahaemolyticus could be enhanced by dye‐sensitized photooxidation, and the photooxidized β‐caryophyllene and the isolated individual compounds could be useful antimicrobial agents to control the growth of S. aureus and V. parahaemolyticus in certain food systems.
Effect of Desiccation, Starvation, Heat, and Cold Stresses on the Thermal Resistance of Enterobacter sakazakii in Rehydrated Infant Milk Formula
Authors: Shaker R.R. , Osaili T.M. , Abu Al‐Hasan A.S. , Ayyash M.M. , Forsythe S.J.
Published: August 2008

ABSTRACT:  Enterobacter sakazakii is an opportunistic foodborne pathogen that has been isolated from powdered infant milk formula. This study determined the effect of desiccation, starvation, heat and cold stresses on the thermal inactivation of E. sakazakii in rehydrated infant milk formula (RIMF). Stressed cells were mixed with RIMF at 52, 54, 56, and 58 °C for various time periods. The D‐ and z‐values were determined by using linear regression analysis. D‐values for unstressed E. sakazakii at 52, 54, 56, and 58 °C were 15.33, 4.53, 2, and 0.53 min, respectively. Desiccation and heat stresses, but not starvation or cold stress, caused significant (P < 0.05) reduction in D‐values. The z‐values of desiccated, starved, heat stressed, and cold stressed E. sakazakii were not significantly different from unstressed cells (4.22 °C). Thermal resistance of E. sakazakii in RIMF is affected by the environmental stresses; that is, desiccation and heat stresses that may surround the bacterium prior to the contamination of infant formula. The results of this study may be of use to regulatory agencies, infant milk producers, and infant caregivers to design heating processes to eliminate E. sakazakii that may be present in infant milk formula.
Effects of Riboflavin Photosensitization on the Changes of Isoflavones in Soymilk
Authors: Lee S.W. , Chang P.‐S. , Lee J.H.
Published: August 2008

ABSTRACT: Effects of riboflavin photosensitization on the distribution of isoflavones in commercially available soymilk were analyzed using high‐performance liquid chromatography (HPLC). Total isoflavones (TI) in soymilk with riboflavin (1000 ppm, w/v) under light were significantly different from those stored in the dark for 24 h (P< 0.05), while TI in samples with 0 and 1000 ppm added riboflavin were not significant from each other in dark conditions (P> 0.05). To test the effects of the concentration of riboflavin on TI, soymilk was mixed with riboflavin to make 0, 100, 250, and 500 ppm (w/v) and stored under light at 25 °C for 24 h. TI in soymilk with 100 ppm riboflavin under light significantly decreased by 13.5% for 24 h (P< 0.05) compared to control samples and were not significantly different from those with 250 or 500 ppm samples (P> 0.05). Daidzin and genistin were predominant isoflavones in soymilk, and the rate of photo degradation of genistin was higher than that of daidzin for 24 h in soymilk under riboflavin photosensitization.
Comparative Evaluation of Yogurt and Low‐Fat Cheddar Cheese as Delivery Media for Probiotic Lactobacillus casei
Authors: Sharp M.D. , McMahon D.J. , Broadbent J.R.
Published: August 2008

ABSTRACT:  This study used Lactobacillus casei 334e, an erythromycin‐resistant derivative of ATCC 334, as a model to evaluate viability and acid resistance of probiotic L. casei in low‐fat Cheddar cheese and yogurt. Cheese and yogurt were made by standard methods and the probiotic L. casei adjunct was added at approximately 107 CFU/g with the starter cultures. Low‐fat cheese and yogurt samples were stored at 8 and 2 °C, respectively, and numbers of the L. casei adjunct were periodically determined by plating on MRS agar that contained 5 μg/mL of erythromycin. L. casei 334e counts in cheese and yogurt remained at 107 CFU/g over 3 mo and 3 wk, respectively, indicating good survival in both products. Acid challenge studies in 8.7 mM phosphoric acid (pH 2) at 37 °C showed numbers of L. casei 334e in yogurt dropped from 107 CFU/g to less than 101 CFU/g after 30 min, while counts in cheese samples dropped from 107 CFU/g to about 105 after 30 min, and remained near 104 CFU/g after 120 min. As a whole, these data showed that low‐fat Cheddar cheese is a viable delivery food for probiotic L. casei because it allowed for good survival during storage and helped protect cells against the very low pH that will be encountered during stomach transit.
Determination of Sodium Chloride in Pork Meat by Computed Tomography at Different Voltages
Authors: Håseth T.T. , Høy M. , Kongsro J. , Kohler A. , Sørheim O. , Egelandsdal B.
Published: August 2008

ABSTRACT:  Ground pork samples simulating the widely different chemical composition of hams during dry‐cured ham production were produced and scanned by x‐ray computed tomography (CT). Chemical composition accounted for most of the variation in CT values (97%). Tube voltage (80, 110, and 130 kV) affected CT value and the effect varied between different types of tissue. Sodium chloride (NaCl) was predicted in the ground samples with average prediction errors (RMSEP) as low as 0.2% to 1.0% NaCl. NaCl was also predicted in small samples of raw to dry‐cured ham. When dry and fat ham samples were left out of the models, NaCl was predicted with a high precision (RMSEP 0.2% to 0.4% NaCl, R2 > 0.99). CT can be used as a valuable, nondestructive tool to analyze distribution of and quantify NaCl in ham during dry‐curing.
Ethanolic Extracts of Antrodia cinnamomea Mycelia Fermented at Varied Times and Scales Have Differential Effects on Hepatoma Cells and Normal Primary Hepatocytes
Authors: Chen Y.‐S. , Pan J.‐H. , Chiang B.‐H. , Lu F.‐J. , Sheen L.‐Y.
Published: August 2008

ABSTRACT:  Mycelia of Antrodia cinnamomea (AC), an edible fungus native to Taiwan, were produced by submerged fermentation with various fermentation times in 250 mL, 5 and 500 L fermentors and were evaluated for the effect of fermentation products on the viabilities of Hep3B and HepG2 hepatoma cells and normal primary rat hepatocytes. The results showed that the ethanolic extracts of AC mycelia (from 250 mL fermentation for 8 wk and 5 and 500 L fermentations for 4 wk) possessed high antihepatoma activity. The IC50 of ethanolic extract of AC mycelia fermented for 8 wk in a 250 mL fermentor against Hep3B and HepG2 cells were 82.9 and 54.2 μg/mL, respectively. Furthermore, the IC50 for Hep3B and HepG2, treated with ethanolic extract of AC mycelia fermented for 4 wk in the 5 L fermentor were 48.7 and 3.8 μg/mL, respectively. Those treated with ethanolic extract of AC mycelia fermented for 4 wk in the 500 L fermentor were 36.9 and 3.1 μg/mL, respectively. No adverse effects of all samples on normal primary rat hepatocytes were observed.
Exploration of twin‐arginine translocation for expression and purification of correctly folded proteins in Escherichia coli
Authors: Fisher Adam C. , Kim Jae‐Young , Perez‐Rodriguez Ritsdeliz , Tullman‐Ercek Danielle , Fish Wallace R. , Henderson Lee A. , DeLisa Matthew P.
Published: August 2008

Historically, the general secretory (Sec) pathway of Gram‐negative bacteria has served as the primary route by which heterologous proteins are delivered to the periplasm in numerous expression and engineering applications. Here we have systematically examined the twin‐arginine translocation (Tat) pathway as an alternative, and possibly advantageous, secretion pathway for heterologous proteins. Overall, we found that: (i) export efficiency and periplasmic yield of a model substrate were affected by the composition of the Tat signal peptide, (ii) Tat substrates were correctly processed at their N‐termini upon reaching the periplasm and (iii) proteins fused to maltose‐binding protein (MBP) were reliably exported by the Tat system, but only when correctly folded; aberrantly folded MBP fusions were excluded by the Tat pathway's folding quality control feature. We also observed that Tat export yield was comparable to Sec for relatively small, well‐folded proteins, higher relative to Sec for proteins that required cytoplasmic folding, and lower relative to Sec for larger, soluble fusion proteins. Interestingly, the specific activity of material purified from the periplasm was higher for certain Tat substrates relative to their Sec counterparts, suggesting that Tat expression can give rise to relatively pure and highly active proteins in one step.
Hypersensitive response and acyl‐homoserine lactone production of the fire blight antagonists Erwinia tasmaniensis and Erwinia billingiae
Authors: Jakovljevic Vladimir , Jock Susanne , Du Zhiqiang , Geider Klaus
Published: August 2008

Fire blight caused by the Gram‐negative bacterium Erwinia amylovora can be controlled by antagonistic microorganisms. We characterized epiphytic bacteria isolated from healthy apple and pear trees in Australia, named Erwinia tasmaniensis, and the epiphytic bacterium Erwinia billingiae from England for physiological properties, interaction with plants and interference with growth of E. amylovora. They reduced symptom formation by the fire blight pathogen on immature pears and the colonization of apple flowers. In contrast to E. billingiae, E. tasmaniensis strains induced a hypersensitive response in tobacco leaves and synthesized levan in the presence of sucrose. With consensus primers deduced from lsc as well as hrpL, hrcC and hrcR of the hrp region of E. amylovora and of related bacteria, these genes were successfully amplified from E. tasmaniensis DNA and alignment of the encoded proteins to other Erwinia species supported a role for environmental fitness of the epiphytic bacterium. Unlike E. tasmaniensis, the epiphytic bacterium E. billingiae produced an acyl‐homoserine lactone for bacterial cell‐to‐cell communication. Their competition with the growth of E. amylovora may be involved in controlling fire blight.
Erythrophore cell response to food‐associated pathogenic bacteria: implications for detection
Authors: Hutchison Janine R. , Dukovcic Stephanie R. , Dierksen Karen P. , Carlyle Calvin A. , Caldwell Bruce A. , Trempy Janine E.
Published: August 2008

Cell‐based biosensors have been proposed for use as function‐based detectors of toxic agents. We report the use of Betta splendens chromatophore cells, specifically erythrophore cells, for detection of food‐associated pathogenic bacteria. Evaluation of erythrophore cell response, using Bacillus spp., has revealed that this response can distinguish pathogenic Bacillus cereus from a non‐pathogenic B. cereus ΔplcR deletion mutant and a non‐pathogenic Bacillus subtilis. Erythrophore cells were exposed to Salmonella enteritidis, Clostridium perfringens and Clostridium botulinum. Each bacterial pathogen elicited a response from erythrophore cells that was distinguished from the corresponding bacterial growth medium, and this observed response was unique for each bacterial pathogen. These findings suggest that erythrophore cell response has potential for use as a biosensor in the detection and toxicity assessment for food‐associated pathogenic bacteria.
Obstructive sleep apnoea syndrome: current status
Authors: Berg S.
Published: August 2008

Introduction:  Obstructive sleep apnoea syndrome (OSAS) is a prevalent condition that covaries with cardiovascular complications and most likely with arterial hypertension and diabetes mellitus.

Objective:  The present paper is a review of the current status of OSAS.

Results:  Definitions and diagnostic criteria as well as known risk factors, prevalence, symptoms, covariance with other diseases and consequences as traffic accidents are described. OSAS is characterised by daytime sleepiness symptoms that range from mild to severe. Risk factors such as anatomical upper airway abnormalities, overweight, smoking, excessive alcohol intake and use of muscle relaxants are related to the development of sleep apnoea. Various diagnostic procedures and treatment modalities are considered. Overnight polysomnography is the reference standard for sleep apnoea recording. Treatment modalities include mechanical [continuous positive airway pressure (CPAP), oral appliances], surgical, pharmacological and ‘conservative’ lifestyle modifications. Finally, Nordic accrediation guidelines for sleep medicine clinics and sleep medicine specialists are described.

Conclusion:  The diagnosis of OSAS should be performed with a polygraph, and the first‐line treatment of moderate to severe OSAS is CPAP. Lastly, compliance for this treatment should be optimised with regular clinical controls.

Please cite this paper as: Berg S. Obstructive sleep apnoea syndrome: current status. The Clinical Respiratory Journal 2008; 2: 197–201.
A change of heart: the new infective endocarditis prophylaxis guidelines
Authors: Daly CG , Currie BJ , Jeyasingham MS , Moulds RFW , Smith JA , Strathmore NF , Street AC , Goss AN
Published: August 2008

New Australian guidelines for the prevention of infective endocarditis were published in July 2008. The guidelines were revised by a multidisciplinary group to reflect recent changes in international recommendations regarding antibiotic prophylaxis for infective endocarditis. The reasons for the changes are explored in this review and the implications for dental practice are discussed.
How does pain affect jaw muscle activity? The Integrated Pain Adaptation Model
Authors: Peck CC , Murray GM , Gerzina TM
Published: August 2008

Pain and limitation of movement are two cardinal symptoms of temporomandibular disorders but it is unclear how one influences the other. The relationship between pain and movement is clinically significant but controversial with two major theories having been proposed: the Vicious Cycle Theory and the Pain Adaptation Model. The Vicious Cycle Theory proposes a vicious cycle between pain and muscle activity. This theory has little scientific basis but underpins many management strategies. The Pain Adaptation Model is more evidence‐based and proposes that pain causes changes in muscle activity to limit movement and protect the sensory‐motor system from further injury. The Pain Adaptation Model has many positive features but does not appear to explain the relation between pain and muscle activity in all situations. We propose that the relationship is influenced by the functional complexity of the sensory‐motor system and the multidimensional nature of pain. This new Integrated Pain Adaptation Model states that pain results in a new recruitment strategy of motor units that is influenced by the multidimensional (i.e., biological and psychosocial) components of the pain experience. This new recruitment strategy aims to minimize pain and maintain homeostasis. This model emphasizes the individual reaction to pain and suggests a tailored approach towards management.
Patient demand for smoking cessation advice in dentist offices after introduction of graphic health warnings in Australia
Authors: Afifah RM , Schwarz E
Published: August 2008

Background: The effectiveness of smoking cessation intervention by dentists has not been conclusively established. This study aimed to investigate whether the inclusion of graphic health warning pictures (including mouth and throat cancer) as part of the Australian National Tobacco Campaign strategy would elicit measurably increased demand for smoking cessation advice in dental practices.

Methods: A cross‐sectional survey of private dental practices in New South Wales, Australia. Separate questionnaires were answered by dentists and patients from their practice. Questions comprised smoking practices and attitudes toward smoking cessation activities in dental practice.

Results: The majority of dentists (85.7 per cent; n = 29) and dental patients (92.4 per cent; n = 800) recalled seeing the graphic health warnings, with mouth and throat cancer the most commonly observed. Television was the main medium. Nineteen per cent of dental patients (n = 152) reported themselves as current smokers. Half of them were planning to quit within six months (49.7 per cent) and agreed that graphic health warnings made them more likely to quit (47.7 per cent). Dentists showed positive attitudes toward cessation activities but believed many patients lacked motivation to quit smoking; a perception that was seen to be the main barrier in offering smoking cessation advice. Forty per cent of smokers would try to quit if asked by their dentists, but only 28.4 per cent preferred a dentist for cessation advice. In general, dentists found no change in demand for smoking cessation advice since the launch of the National Tobacco Campaign in 2006.

Conclusions: Health warning pictures seemed to increase the patients’ awareness and intention to quit smoking, however it did not appear to generate more demand for smoking cessation advice from their dentists. Dentists had low expectations about their patients’ motivation to stop smoking.
Development and testing of revised practice belief scales among private general dental practitioners
Authors: Brennan DS , Spencer AJ
Published: August 2008

Background:  Practice beliefs have been related to service rate variation and appropriateness of care. The aim of this paper was to further develop practice belief scales by adding new items to an existing set and testing associations with dentist and practice characteristics, and services provided.

Methods:  Practice belief items were recorded on a five‐point Likert scale using mailed questionnaires from a random sample of dentists in 2004 (response rate = 76.8 per cent).

Results:  Factor analysis yielded five factor‐based scales, with three having adequate or near adequate internal consistency: Professional Autonomy (α = 0.72), Patient Focus (α = 0.71) and Preventive Orientation (α = 0.59). Responses were skewed towards strongly agree (scores 1–<2) for Professional Autonomy (60.6 per cent), Patient Focus (71.7 per cent) and Preventive Orientation (46.3 per cent). Higher percentages of dentists with strong agreement on Patient Focus were aged 30–39 and 60+ years, while lower percentages of dentists with strong agreement on Preventive Orientation were male (Chi‐square, P < 0.05). Those strongly agreeing with the scales (scores 1–<2) had (Poisson regression; P < 0.05): lower rates of restorative, a rate ratio (RR) of 0.93, dentures (RR = 0.72) and extractions (RR = 0.63) for Professional Autonomy; higher rates of dentures (RR = 1.32), crowns (RR = 1.46) and extractions (RR = 1.47) for Patient Focus; and lower rates of restorative (RR = 0.88), dentures (RR = 0.78), crowns (RR = 0.72), extractions (RR = 0.50), endodontics (RR = 0.80), but a higher rate of scaling (RR = 1.13) for Preventive Orientation.

Conclusions:  The findings confirmed some of an earlier factor structure of practice beliefs, extended the potential practice belief domains, and demonstrated associations with service rates.
Dental service provision in Victorian residential aged care facilities
Authors: Hopcraft MS , Morgan MV , Satur JG , Wright FAC
Published: August 2008

Background:  The Australian population is ageing, and a growing proportion of elderly Australians are now living in residential aged care facilities (RACFs). These residents are at high risk of developing dental diseases, have more teeth present now than at any time in the past 50 years and often have difficulty maintaining adequate oral hygiene. Traditionally, dental service provision has been problematic and sporadic for these residents.

Methods:  A postal survey of a random sample of Victorian general dentists and Directors of Nursing (DONs) of Victorian RACFs was undertaken in 2006 to ascertain the participation of dentists in the provision of dental care and to identify factors impacting on the organization and provision of dental care for residents.

Results:  The response rate for dentists was 57.3 per cent, and for DONs 64.4 per cent. Half of the dentists reported that they had provided care to residents of aged care facilities in the past 12 months, and they spent an average of one hour per month providing care. Overall, dentists were concerned with their level of undergraduate education and training in various aspects of dentistry for residents of aged care facilities. DONs reported significant difficulty obtaining adequate dental care for their residents. Common problems identified by both dentists and DONs included a preference for dentists to treat residents in their own practice, dentists not willing to go to RACFs and a lack of portable dental equipment for dentists to use.

Conclusions:  There were low levels of interest and participation from Victorian dentists in providing dental care for residents of aged care facilities. Dentists had a strong preference for treating patients at their own practice, and there were a number of significant barriers that appeared to impact on the provision of dental care in RACFs.
Facial fractures in road cyclists
Authors: Lee KH , Chou H‐J
Published: August 2008

Background:  Despite the safety devices worn by bicycle riders and the road safety measures designed to protect them, road cycling is still associated with frequent traumas, notably to the extremities. Maxillofacial injuries are common, especially when road traffic accidents occur. There is a paucity of literature on the epidemiology of bicycle‐related facial fractures in New Zealand.

Methods:  A retrospective database of patients presenting to the Oral and Maxillofacial Surgery Unit at Christchurch Hospital during an 11‐year period was reviewed. Variables examined included demographics, types of fracture, mode of injury, and treatment delivered.

Results:  Sixty‐three patients were identified as having road bicycle‐related facial fractures, with no increase in prevalence over the study period. Male to female ratio was 3:1, with 76 per cent involving patients aged between their first and third decade. Fall was the most common mechanism of injury, followed by collision. Fifty‐two per cent of patients were hospitalized and 40 per cent required surgical intervention. The highest incidence of injury was during January.

Conclusions:  Road bicycle‐related fractures accounted for a small proportion of the workload at our unit. They predominantly affected young male adults. More than half of the patients were hospitalized and a major proportion of these required surgery.
Early detection of white spot lesions with digital camera and remineralization therapy
Authors: Iijima Y
Published: August 2008

Background:  In this paper, the characteristics of the early stage of dental caries are discussed and the methods we used to treat the early stage of dental caries to increase the number of caries‐free patients are presented. Studies from in vitro to in situ experiments and a clinical study were carried out to support clinical remineralization therapy.

Methods and results:  To clarify the effect of time for remineralization, the degree of remineralization was assessed at 2 days, 6 days, and 10 days after 2‐day demineralization in 0.01 M/L lactic acid buffer (pH 4.0 at 37°). The remineralization solution contained 3.0 mM/L Ca, 1.8 mM/L P, and 3 ppm fluoride adjusted to pH 7.0. A 10‐day continuous remineralization with a 3 ppm fluoride resulted in a high fluoride concentration. To evaluate mineral loss from sound tooth structure and white spot lesions, thin sections (about 90 μm) including white spots (WS) were prepared and exposed to oral conditions for 2 weeks continuously. The mineral loss from sound tooth structure was found to be twice that from WS. In another experiment during the remineralization period, enamel samples were immersed in three different bicarbonate solutions; 0.5, 5.0 and 50 mM/L for 30 minutes, two times per day. Both the bicarbonate and fluoride applied groups showed higher improvement in acid resistance and the amount of remaining mineral was almost two times higher than the controls (p < 0.01). In a clinical study we demonstrated remineralization in patients who followed professional mechanical tooth cleaning and fluoride prophylaxis paste. Using this regime, in patients with deciduous caries present at baseline, over 80 per cent of permanent teeth were caries free at the age of 12 years. In these studies the digital camera with CasMaTCH™ and an image analysis system showed several advantages for monitoring in de‐ and remineralization.

Conclusions:  White spot lesions, rather than intact tooth surfaces, can be mineralized through the daily clinical procedures described in this paper.
Remineralization of deep enamel dentine caries lesions
Authors: Ten Cate JM
Published: August 2008

Enamel remineralization is generally studied in superficial (up to 100 μm) lesions, but in vivo caries lesions may be tenfold deeper. This article addresses the question whether deep lesions, and extending into dentine, can be remineralized under optimal conditions and if this process is influenced by agents affecting calcium phosphate precipitation and dissolution. Lesions through enamel into dentine were first formed in thin sections and then continuously remineralized for periods up to 200 days. With longitudinal assessment by transversal microradiography it was showed that remineralization throughout the depth of the lesion and into the dentine was possible, although this process is very slow. Fluoride and bisphosphonate treatments affected mainly the deposition in the outer enamel. Although it was assumed that this would affect the diffusion of ions to deeper layers, the treatments had no impact on remineralization in the inner enamel or dentinal parts of the lesions. These findings are discussed with relevant theoretical considerations, and in their possible clinical implications.
The effects of N‐acetylcysteine on the expression of matrix metalloproteinase‐2 and tissue inhibitor of matrix metalloproteinase‐2 in hepatic fibrosis in bile duct ligated rats
Authors: Rezaei Arezou , Ardestani Sussan Kaboudanian , Forouzandeh Mehdi , Tavangar Seyed Mohammad , Khorramizadeh Mohammad Reza , Payabvash Seyedmehdi , Nezami Behtash Ghazi , Jahanshiri Zahra , Tavakoli Zahra , Shariftabrizi Ahmad , Dehpour Ahmad Reza
Published: August 2008

Aim: N‐acetylcysteine can inhibit the formation of intracellular reactive oxygen intermediates. Cellular redox state plays a role in regulating the secretion of matrix metalloproteinase‐2. We investigated the effects of N‐acetylcysteine on the expression of matrix metalloproteinase‐2 and tissue inhibitor of matrix metalloproteinase‐2.

Methods: Bile duct ligated rats were used as a model of hepatic fibrosis. We compared the level of gene expression (using real‐time reverse transcription polymerase chain reaction [RT–PCR]), liver function parameters, hepatic reactive oxygen production, lipid peroxidation and glutathione state in experimental groups.

Results: N‐acetylcysteine treatment significantly improved liver function parameters including the plasma levels of aspartate aminotransferase, alkaline phosphatase, gamma‐glutamyl transpeptidase and bilirubin. In addition, significant improvement of glutathione state and reactive oxygen production were observed. Hepatic lipid peroxidation was reversed by N‐acetylcysteine treatment. Although N‐acetylcysteine treatment did not completely normalize the increased matrix metalloproteinase‐2 expression, it significantly decreased its level by 65%. N‐acetylcysteine treatment also significantly decreased matrix metalloproteinase‐2 activity and normalized tissue inhibitor of matrix metalloproteinase‐2 expression.

Conclusion: Collectively, N‐acetylcysteine showed inhibition of matrix metalloproteinase‐2 expression and activity. In addition, administration of N‐acetylcysteine was associated with downregulation of the expression of tissue inhibitor of matrix metalloproteinase‐2 and amelioration of oxidative stress in the liver of bile duct ligated rats.
In vivo interferon system assessed by 2′‐5′ oligoadenylate synthetase activity in chronic hepatitis C virus patients treated with pegylated interferon and ribavirin
Authors: Shindo Michiko , Hamada Kazushige , Morikawa Teruhisa , Harano Yuichi , Nakajima Tomoaki , Okuno Tadao
Published: August 2008

Aim:  2′,5′ oligoadenylate synthetase (2‐5AS), an enzyme induced by interferon, is an accurate indicator of the antiviral effect of interferon. We measured it during pegylated interferon based therapies in patients with chronic hepatitis C virus (HCV) in order to determine the dynamics of antiviral status in vivo and the relationship between the response to exogenous interferon and the outcome of therapy.

Methods:  A total of 160 patients with chronic HCV were treated with pegylated interferon alfa 2a or 2b or non‐pegylated interferon, with or without ribavirin. Serum 2‐5AS activity was measured by radioimmunoassay assay kits every 2 weeks.

Results:  In 60 patients treated with pegylated interferon alfa 2a or 2b, 2‐5AS levels increased to 7–40 times (average 235 pmol/dL) above the pretreatment levels (30 pmol/dL), which were significantly higher than the levels during non‐pegylated interferon therapy. Ribavirin did not enhance 2‐5AS levels. 2‐5AS levels between sustained virological response (SVR) and non‐SVR, including null responders to pegylated interferon plus ribavirin therapy were not significantly different.

Conclusion:  2‐5AS levels were significantly higher in patients treated with pegylated interferon than in those treated with non‐pegylated interferon, suggesting that pegylated interferon is more potent at inducing interferon response genes resulting in an improved antiviral effect. Ribavirin did not appear to be related to interferon response gene induction.