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The aim of this study is to evaluate risk factors for non-attendance to post-discharge, hospital follow-up appointments for traumatically injured patients who underwent exploratory laparotomy.This is a retrospective chart review of patients who underwent exploratory laparotomy for traumatic abdominal injury at an urban, Midwestern, level I trauma center with clinic follow-up scheduled after discharge. Clinically, relevant demographic characteristics, patients' distance from hospital, and the presence of staples, sutures, and drains requiring removal were collected. Descriptive statistics of categorical variables were calculated as totals and percentages and compared with a chi-squared test or Fisher's exact when appropriate.The sample included 183 patients who were largely assaultive trauma survivors (68%), male (80%), and black (53%) with a mean age of 35.4 ± 14.9 years. Overall, 18.5% no-showed for their follow-up appointment. On multivariate analysis for clinic no-show; length of stay (odds ratio = 0.92 [0.84-0.99], P = 0.04) and the need for suture, staple, or drain removal were protective for clinic attendance (odds ratio = 5.59 [1.07-7.01], P = 0.04). Overall, 12 patients (6.4%) were readmitted. Forty patients (18.3%) had their follow-up in the emergency department (ED). On multivariate regression of risk factors for ED visits, the only statistically significant factors (P 0.05) were clinic appointment no-show (OR = 2.81) and self-pay insurance (OR = 4.78).Abdominal trauma patients are at high risk of no-show for follow-up appointments and no-show visits are associated with ED visits. Future work is needed evaluating interventions to improve follow-up.

The prevalence of super obesity (SO, BMI > 50.0 kg/m2) and super-super obesity (SSO, BMI > 60 kg/m2) is increasing. Current data are limited and discrepant on the relationship between SSO and post-bariatric surgery complication risk. We hypothesized there would be increased complications for both laparoscopic Roux-en-Y gastric bypass (LRYGB) and sleeve gastrectomy (LSG) in SSO compared to SO, but the relative risk (RR) would support the use of LSG in SSO patients. Metabolic and Bariatric Surgery Accreditation and Quality Improvement 2016 data were queried for SO and SSO patients undergoing LRYGB or LSG. Thirty-day post-operative complications were calculated. Univariate analyses were performed with a χ2 or Student’s t test. Comparisons between multiple groups were performed using a one-way ANOVA. Statistical significance was defined as p

The purpose of this study was to determine whether or not the dual constant-depth film fermenter (dCDFF) is able to produce caries-like enamel lesions and to ascertain further information regarding the performance of this fully functional biological caries model. Conditions were defined by the continuation (CF) or cessation (FF) of a saliva-type growth medium supply during 50-mM sucrose exposures (8 times daily). Hydroxyapatite (n = 3) and bovine enamel (n = 3) substrata were included within each condition and samples extracted after 2, 4, 8, and 16 days. Community profiles were generated for fastidious anaerobes, Lactobacillus spp., Streptococcus spp., mutans streptococci (MS), and Veillonella spp. using selective culture techniques and enamel demineralisation assessed by transverse microradiography. Results demonstrated that the dCDFF model is able to produce caries-like enamel lesions with a high degree of sensitivity where reduced ionic strength within the FF condition increased surface layer mineral deposition. Between conditions, biofilm communities did not differ significantly, although MS in the biofilms extracted from the FF condition rose to a higher proportion (by 1.5 log10 units), and Veillonella spp. were initially greater within the CF condition (by 2.5 log10 units), indicating an enhanced ability for the clearance of low-pKa acids following exposures to sucrose. However, both conditions retained the ability for caries-like lesion formation.

We present the rare case of a small bowel obstruction secondary to pelvic organ prolapse (POP). A 77-year-old female presented with four days of abdominal pain, nausea, and vomiting. She had a history of abdominal hysterectomy with bilateral salpingo-opherectomy and a mildly symptomatic cystocele. She was found to have an enterocele causing small bowel obstruction. The enterocele was manually reduced and subsequently managed non-operatively with a pessary. Prior case reports of small bowel obstructions secondary to POP required emergent surgical intervention. Post-menopausal women should be asked about symptoms or presence of pelvic organ prolapse and in the correct patient population, pelvic examination can be important for diagnosis and treatment of small bowel obstruction. If the enterocele is manually reduced non-operative management can be safe and effective.

Progress in the treatment of triple-negative breast cancer remains an important challenge. Given the aggressive biology and high risk of distant recurrence, systemic chemotherapy is warranted in most patients. Neaodjuvant chemotherapy benefits patients with locally advanced disease by downsizing the tumor and increasing the probability of breast-conserving surgery. Clinical and pathologic responses provide important prognostic information, which makes neoadjuvant therapy an attractive approach for all patients with triple-negative breast cancer. Clinical research in the neoadjuvant setting is focused on improvement in pathologic complete response rates and outcomes of patients with residual disease.

A number of anaerobic oral bacteria, notably Prevotellaceae, exhibit red fluorescence when excited by short-wavelength visible light due to their accumulation of porphyrins, particularly protoporphyrin IX. pH affects the fluorescence of abiotic preparations of porphyrins due to transformations in speciation between monomers, higher aggregates, and dimers. To elucidate whether the porphyrin speciation phenomenon could be manifested within a microbiological system, suspensions of Prevotella intermedia and Prevotella nigrescens were examined by fluorescence spectrophotometry while being titrated against NaOH. The initial pH of the samples was6, which was then raised toward the maximum found within a diseased periodontal pocket, being ∼pH 8.7. The intensity of the fluorescence emissions increased between 600 and 650 nm with increasing pH. Peak fluorescence emissions occurred at 635±1 nm with a second emission peak developing with increasing pH at 622 nm. A linear relationship was demonstrated between pH and the log10 ratio of 635:622 nm excitation fluorescence intensities. These findings suggest that the pH range found within the oral cavity could affect the fluorescence of oral bacteria in vivo, which may in turn have connotations for any clinical diagnoses that may be inferred from dental plaque fluorescence.

Phosphate-based glasses (PBGs) are excellent controlled delivery agents for antibacterial ions such as silver and gallium. The aim of this study was to assess the potential utility of novel PBGs combining both gallium and silver for use in periodontal therapy. To this end, an in vitro biofilm model with the putative periodontal pathogen, Porphyromonas gingivalis, and an initial colonizer, Streptococcus gordonii, was established. The effect of increasing calcium content in gallium-silver-doped PBG on the susceptibility of P. gingivalis was examined. A decrease in degradation rates (30.34, 25.19, 21.40 μg mm(-2) h(-1)) with increasing PBG calciumcontent (10, 11, 12 mol.% respectively) was observed, correlating well with gallium and silver ion release and antimicrobial activity against planktonic P. gingivalis (approximately 5.4log(10) colony-forming units (CFU) reduction after 24h by the C10 glass compared with controls) and S. gordonii (total growth inhibition after 32h by C10, C11 and C12 glasses compared with controls). The most potent PBG (C10) was evaluated for its ability to inhibit the biofilm growth of P. gingivalis in a newly established constant-depth film fermentor model. The simultaneous release of silver and gallium from the glass reduced P. gingivalis biofilm growth with a maximum effect (1.92log(10) CFU reduction) after 168 h. Given the emergence of antibiotic-resistant bacteria and dearth of new antibiotics in development, the glasses, especially C10, would offer effective alternatives to antibiotics or may complement current therapies through controlled, localized delivery of gallium and silver ions at infected sites in the oral cavity.

Surfing is a unique recreational activity with the possibility of elevated risk for contracting gastrointestinal (GI) illness through ingestion of contaminated water. No prior studies have assessed exposure from ingestion among surfing populations. This study estimated the magnitude and frequency of incidental water ingestion using a Web-based survey and integrated exposure distributions with enterococci distributions to predict the probability of GI illness at six Oregon beaches. The mean exposure magnitude and frequency were 170 ml of water ingested per day and 77 days spent surfing per year, respectively. The mean number of enterococci ingested ranged from approximately 11 to 86 colony-forming units (CFU) per day. Exposure-response analyses were conducted using an ingested dose model and two epidemiological models. Risk was characterized using joint probability curves (JPC). At the most contaminated beach, the annualized ingested dose model estimated a mean 9% probability of a 50% probability of GI illness, similar to the results of the first epidemiological model (mean 6% probability of a 50% probability of GI illness). The second epidemiological model predicted a 23% probability of exceeding an exposure equivalent to the U.S. Environmental Protection Agency (EPA) maximum acceptable GI illness rate (19 cases/1000 swimmers). While the annual risk of GI illness for Oregon surfers is not high, data showed that surfers ingest more water compared to swimmers and divers and need to be considered in regulatory and public health efforts, especially in more contaminated waters. Our approach to characterize risk among surfers is novel and informative to officials responsible for advisory programs. It also highlights the need for further research on microbial dose-response relationships to meet the needs of quantitative microbial risk assessments (QMRA).

A problem with tissue engineering scaffolds is maintaining seeded cell viability and function due to limitations of oxygen and nutrient transfer. An approach to maintain suitable oxygen concentrations throughout the scaffold would be to controllably incorporate microchannelling within these scaffolds. This study investigated the incorporation of unidirectionally aligned soluble phosphate based glass fibers (PGF) into dense collagen scaffolds. PGF are degradable, and their degradation can be controlled through their chemistry and dimensions. Plastic compression was used to produce composite scaffolds at three different weight percentage while maintaining greater than 80% resident cell viability. PGF-collagen scaffold composition was quantified through thermogravimetric analysis as well as being morphologically and mechanically characterized. PGF degradation was measured through ion chromatography, and channel formation was verified with ultrasound imaging and SEM. The free movement of coated microbubble agents confirmed the channels to be continuous in nature and of 30-40 microm diameter. These microchannels in dense native collagen matrices could play an important role in hypoxia/perfusion limitations and also in the transportation of nutrients and potentially forming blood vessels through dense implants.

Ecological risk assessment has grown and evolved since the 1980s, as have new challenges (e.g. global climate change, loss of habitat and biodiversity and the effects of multiple anthropogenic chemicals on ecological systems) that need to be factored into the risk assessment processes. There is also an on-going shift from evaluating adverse health impacts on particular, often small scale, environments to undertaking more complex ecological assessments of whole populations and communities across ecologically meaningful landscapes. These trends are generating an increased demand for much more complex ecological assessments, making it increasingly clear that to achieve its potential as a management tool, methods must be developed to apply ecological risk assessment to larger and more complex scales. This paper reviews the development of the ecological risk assessment paradigm in the United States, identifies ways it is being applied and adapted in other countries, explores future research needs and practice improvements, and examines current issues that need to be considered in taking forward the scientific development of ecological risk assessment as a useful environmental management tool. Keywords: Ecological risk assessment, Management, Probabilistic, Landscape scale, Trends

Although estimates vary, there is a broad agreement that invasive species impose major costs on the U.S. economy, as well as posing risks to nonmarket environmental goods and services and to public health. The domestic effort to manage risks associated with invasive species is coordinated by the National Invasive Species Council (NISC), which is charged with developing a science-based process to evaluate risks associated with the introduction and spread of invasive species. Various international agreements have also elevated invasive species issues onto the international policy agenda. The World Trade Organization (WTO) Sanitary and Phytosanitary (SPS) Agreement establishes rights and obligations to adhere to the discipline of scientific risk assessment to ensure that SPS measures are applied only to the extent required to protect human, animal, and plant health, and do not constitute arbitrary or unjustifiable technical barriers to trade. Currently, however, the field of risk assessment for invasive species is in its infancy. Therefore, there is a pressing need to formulate scientifically sound methods and approaches in this emerging field, while acknowledging that the demand for situation-specific empirical evidence is likely to persistently outstrip supply. To begin addressing this need, the Society for Risk Analysis Ecological Risk Assessment Specialty Group and the Ecological Society of America Theoretical Ecology Section convened a joint workshop to provide independent scientific input into the formulation of methods and processes for risk assessment of invasive species to ensure that the analytic processes used domestically and internationally will be firmly rooted in sound scientific principles.

Aims. The aim of this study was to use confocal laser scanning microscopy (CLSM) to examine the spatial distribution of both viable and non-viable bacteria within microcosm dental plaques grown in vitro. Previous in vivo studies have reported upon the distribution of viable bacteria only. Methods and Results. Oral biofilms were grown on hydroxyapatite (HA) discs in a constant-depth film fermenter (CDFF) from a saliva inoculum. The biofilms were stained with the BacLightTM LIVE/DEAD system and examined by CLSM. Fluorescence intensity profiles through the depth of the biofilm showed an offset between the maximum viable intensity and the maximum non-viable intensity. Topographical differences between the surface properties of the viable and non-viable biofilm virtual surfaces were also measured Conclusions. The profile of fluorescence intensity from viable and non-viable staining suggested that the upper layers of the biofilm contain proportionally more viable bacteria than the lower regions of the biofilm. Significance and Impact of Study. Viability profiling records the transition from predominantly viable to non-viable bacteria through biofilms suggesting that this technique may be of use for quantifying the effects of antimicrobial compounds upon biofilms. The distribution of viable bacteria was similar to that found in dental plaque in vivo suggesting that the CDFF produces in vitro biofilms which are comparable to their in vivo counterparts in terms of the spatial distribution of viable bacteria.

Background and Objectives Oral bacteria can be killed by light in the presence of a suitable photosensitizer, and this could be used in the treatment of oral infections. In these diseases, however, bacteria are present as biofilms, which are refractive to antimicrobial agents. The purpose of this study was to determine whether oral bacterial biofilms were susceptible to lethal photosensitization. Study Design/Materials and Methods Multi-species biofilms of oral bacteria were irradiated with light from a helium/neon laser in the presence of toluidine blue O (TBO) and the survivors enumerated. Controls examining the effects of light and TBO alone were also included. The biofilms were also examined by confocal scanning laser microscopy (CSLM). Results CSLM revealed that the biofilms had structures similar to those of dental plaque. Although, the biofilms consisted of extremely large numbers of bacteria (∼9 × 109), 97.4% were killed following irradiation with 31.5 J of laser light in the presence of 25 μg/ml TBO. Conclusions Substantial numbers of oral bacteria in multi-species biofilms can be killed by light in the presence of TBO. This may be useful in the treatment of dental plaque-related diseases. Lasers Surg. Med. 31:86–90, 2002. © 2002 Wiley-Liss, Inc.

The aim of this study was to investigate the purported link between oral hygiene and preterm birth by using image analysis tools to quantify dental plaque biofilm. Volunteers (n=91) attending an antenatal clinic were identified as those considered to be “at high risk” of preterm delivery (i.e., a previous history of idiopathic preterm delivery, case group) or those who were not considered to be at risk (control group). The women had images of their anterior teeth captured using quantitative light-induced fluorescence (QLF). These images were analysed to calculate the amount of red fluorescent plaque (ΔR%) and percentage of plaque coverage. QLF showed little difference inΔR% between the two groups, 65.00% case versus 68.70% control, whereas there was 19.29% difference with regard to the mean plaque coverage, 25.50% case versus 20.58% control. A logistic regression model showed a significant association between plaque coverage and case/control status (P=0.031), controlling for other potential predictor variables, namely, smoking status, maternal age, and body mass index (BMI).

In typical exposure models, dose is a function of ingestion rate, which is a function of field metabolic rate and food energy availability. It is implicitly assumed that neither food energy nor ingestion rate is limited. This is unlikely to be true in the field. Poor habitat quality (expressed as limited or lacking food energy) or a physiologically limited maximum ingestion rate may collectively limit energy intake. A receptor may thus be as much at risk from lack of energy as from toxicant effects. To explore this possibility, an existing spatially explicit exposure model (SE3M) was enhanced to: 1) express ‘habitat quality’ in terms of gross energy available from a suite of habitat-specific food types, 2) track fulfillment of a receptor’s daily energy needs as it traverses habitat patches with varying gross energy levels, 3) link intake of contaminants to food consumed to meet daily energy needs, and 4) track contaminant doses and resulting tissue residue levels as a receptor moves through habitat patches with differing levels of contamination. A feedback term through which chemical stressors affect a receptor’s ability to intake and process energy was not considered at this time. The now spatially and energetically explicit exposure model, SE4M, provides a platform for exploring spatial and bioenergetic factors that may influence a receptor’s acquisition of energy and contaminant tissue residues as it moves through space and time. An application of this model would be to provide predictions of tissue residue levels that are accessible to calibration or validation with empirical field data.

Electric toothbrushes were evaluated using a model of plaque removal by fluid shear forces. Sucrose supplementation during plaque development did not affect the removal of bacteria from biofilm exposed to low-energy shear but did increase their resistance to high-energy shear. The toothbrush supplying high-energy shear forces removed significantly more viable bacteria.

Formalin is a known carcinogen, so there is a need to establish whether a safer alternative is available for the sterilization of human teeth destined for use in clinical training. Any disinfectant that is not capable of sterilizing 100 percent of the samples tested should be considered a failure. In this study, biofilms of oral bacteria were grown on previously autoclaved extracted human teeth. These biofilm-laden teeth were then screened against a range of disinfectants for an exposure time of seven days in a laboratory refrigerator. Culture methods were employed to validate the sterility of the tooth samples. Five percent Virkon and Gigasept PA proved effective against the laboratory model of disinfection and were carried forward to challenge freshly extracted human teeth. Gigasept PA was the only disinfectant that sterilized 100 percent of the tooth samples. Gigasept PA should be considered a safer and effective alternative to formalin for the sterilization of extracted teeth destined for teaching purposes.

It is expedient to consider new ways in which dementia care services may be configured to meet increasing demographic, societal and regulatory demands. Greater equity in the distribution of clinical responsibility across multidisciplinary teams has been suggested as one method that may offer a range of benefits to both the service user and the service itself. However, within the dementia workforce there are concerns about inconsistency and variability in both knowledge of dementia and competency in meeting the needs of those affected. Taking this into account it was felt important to explore perceived knowledge and competency of specialist dementia care nurses who would not only be expected to possess higher levels of knowledge and skill but are positioned as the obvious clinical group to engage with new ways of working. Consequently, this paper offers the results and subsequent discussion of a survey of senior nurses working in dementia care across the UK.

Many species of oral bacteria can be induced to fluoresce due to the presence of endogenous porphyrins, a phenomenon that can be utilized to visualize and quantify dental plaque in the laboratory or clinical setting. However, an inevitable consequence of fluorescence is photobleaching, and the effects of this on longitudinal, quantitative analysis of dental plaque have yet to be ascertained.Filter membrane biofilms were grown from salivary inocula or single species (Prevotella nigrescens and Prevotella intermedia). The mature biofilms were then examined in a custom-made lighting rig comprising 405 nm light-emitting diodes capable of delivering 220 W/m(2) at the sample, an appropriate filter and a digital camera; a set-up analogous to quantitative light-induced fluorescence digital. Longitudinal sets of images were captured and processed to assess the degradation in red fluorescence over time.Photobleaching was observed in all instances. The highest rates of photobleaching were observed immediately after initiation of illumination, specifically during the first minute. Relative rates of photobleaching during the first minute of exposure were 19.17, 13.72 and 3.43 arbitrary units/min for P. nigrescens biofilms, microcosm biofilm and P. intermedia biofilms, respectively.Photobleaching could be problematic when making quantitative measurements of porphyrin fluorescence in situ. Reducing both light levels and exposure time, in combination with increased camera sensitivity, should be the default approach when undertaking analyses by quantitative light-induced fluorescence digital.

An extracted tooth model of endodontic irrigation, incorporating reproducible inoculation and irrigation procedures, was tested against Enterococcus faecalis using a variety of different irrigants in a Latin square methodology. ANOVA revealed no significant variations between the twelve teeth or experiments undertaken on different occasions; however, variation between irrigants was significant.

Endodontic restorations often fail due to inadequate disinfection of the root canal even though the antimicrobial irrigants used have been shown to be capable of killing the bacterium frequently implicated in this complication, Enterococcus faecalis (Ef). Extracted human teeth were root-prepared and filled with a liquid culture of Ef. Following incubation, the root canals were irrigated with 1% sodium hypochlorite (NaOCl), electrochemically activated water or saline control. Irrigation was modelled using an electronic pipette to deliver the solutions at a reproducible flow velocity. A series of parallel experiments employed a membrane biofilm model that was directly immersed into irrigant. Experimental conditions where contiguous between the extracted tooth model and biofilm model wherever possible. After 60 s of exposure, 1% NaOCl effectively sterilised the biofilm model, whereas log 3.36 viable Ef where recoverable from the analogous extracted tooth model, the other irrigants proved ineffective. Biofilms of Ef were susceptible to concentrations of irrigant that proved ineffective in the tooth model. NaOCl was the most effective biocide in either case. This suggests that the biofilm modality of bacterial growth may not be the most important factor for the recalcitrance of root canal infections during endodontic irrigation; it is more likely due to the inability of the irrigant to access the infection.

Objectives: It has been demonstrated that the efficiency of lethal photosensitization can be improved by covalently binding photosensitizing agents to bacteriophage. In this study we have investigated whether a bacteriophage requires the capacity to infect the bacterium to enhance lethal photosensitization when linked to a photosensitizer. Methods: Tin (IV) chlorin e6 (SnCe6) was conjugated to bacteriophage F11, a transducing phage that can infect Staphylococcus aureus NCTC 8325-4, but not epidemic methicillin-resistant S. aureus (EMRSA)-16. The conjugate and appropriate controls were incubated with these bacteria and either exposed to laser light at 632.8 nm or kept in the dark. Results: The SnCe6/F11 conjugate achieved a statistically significant reduction in the number of viable bacteria of both 8325-4 and EMRSA-16 strains by 2.31 log10 and 2.63 log10, respectively. The conjugate could not however instigate lethal photosensitization of Escherichia coli. None of the other combinations of controls, such as an equivalent concentration of SnCe6 only, an equivalent titre of bacteriophage only or experiments conducted without laser light, yielded significant reductions in the number of viable bacteria recovered. Conclusions: The inability of a bacteriophage to infect S. aureus does not prevent it from specifically delivering a photosensitizer to a bacterium enabling its lethal photosensitization.

The accumulation of dental plaque below the gingival margin (i.e. subgingival plaque) is responsible for the most prevalent microbe-induced diseases of humans — the periodontal diseases. Access to this plaque is difficult, making studies of its structure in vivo very difficult. We have, therefore, used a constant-depth film fermenter to grow microcosm subgingival dental plaques under conditions similar to those existing in vivo to enable us to study certain aspects of its structure. Confocal laser scanning microscopy revealed that the biofilms consisted of pillar-like stacks of bacteria separated by water channels. In terms of their structure, these microcosm dental plaques reached a pseudo steady-state after 4 days. Individual optical sections generally showed the outer layers of the biofilm stacks to contain a high proportion of nonviable cells surrounding an inner core of predominantly viable cells with ‘veins’ of nonviable bacteria penetrating from the outer layers through into the inner core. Such a structure differs from that classically described for biofilms growing in an aerobic atmosphere where the arrangement of viable and nonviable bacteria is usually reversed. The reasons for the preponderance of nonviable bacteria in the outer layer of the bacterial stacks remain to be established.

Multispecies biofilms modeling interproximal plaque were grown on a hydroxyapatite substratum in a constant-depth film fermentor and then immersed in a viewing solution containing fluorescent indicators of membrane integrity. Confocal laser scanning microscopy (CLSM) revealed the structure and spatial distribution of cell vitality within the biofilms. Chlorhexidine gluconate (CHX) was added to the viewing solution to achieve concentrations of 0.05 and 0.2% (wt/vol) before further CLSM time-lapse series were captured. Image analysis showed that exposure to 0.2% CHX caused the biofilm to contract at a rate of 1.176 μm min −1 along the z axis and also effected changes in total fluorescence measurements and viability profiles through the biofilms after a delay of 3 to 5 min. At a concentration of 0.05% CHX, total fluorescence measurements for the biofilm exhibited barely detectable changes after 5 min. Fluorescence profiles (fluorescence versus time versus depth), however, clearly showed that a time-dependent effect was present, but the clearest indicator of the effect of dilute CHX over time was viability profiling. These findings suggest the possibility of using fluorescent indicators of membrane integrity in conjunction with viability profiling to evaluate the penetration of the bactericidal effects of membrane-active antimicrobial compounds into biofilm.

In the Willamette River Basin (WRB, Oregon, USA), health advisories currently limit consumption of fish that have accumulated methylmercury (MeHg) to levels posing a potential health risk for humans. Under the Clean Water Act, these advisories create the requirement for a total maximum daily load (TMDL) for mercury in the WRB. A TMDL is a calculation of the maximum amount of a pollutant that a body of water can receive and still meet water-quality standards. Because MeHg is known to biomagnify in aquatic food webs, a basin-specific biomagnification factor can be used, given a protective fish tissue criterion, to estimate total mercury concentrations in surface waters required to lower advisory mercury concentrations currently in fish in the WRB. This paper presents an aquatic food web biomagnification model that simulates inorganic mercury (Hg(II)) and MeHg accumulation in fish tissue and estimates WRB-specific biomagnification factors for resident fish species of concern to stakeholders. Probabilistic (two-dimensional Monte Carlo) techniques propagate parameter variability and uncertainty throughout the model, providing decision makers with credible range information and increased flexibility in establishing a specific mercury target level. The model predicts the probability of tissue mercury concentrations in eight fish species within the range of concentrations measured in these species over 20 years of water-quality monitoring. Estimated mean biomagnification factor values range from 1.12 x 10(6) to 7.66 x 10(6) and are within the range of U.S. Environmental Protection Agency national values. Several WRB-specific mercury target levels are generated, which very by their probability of affording human health protection relative to the federal MeHg tissue criterion of 0.30 mg/kg. Establishing a specific numeric target level is, however, a public policy decision, and one that will require further discussions among WRB stakeholders.

The aim of this study was to compare the efficacy of interproximal plaque removal by the hydrodynamic shear forces produced by 2 electric toothbrushes (toothbrush A, Sonicare Plus and toothbrush B, Braun Oral B) using laboratory-grown plaque biofilms in an anatomically correct in vitro brushing model.In vitro oral biofilms were grown in a constant-depth film fermenter on hydroxyapatite (HA) discs. Brushing experiments were conducted in a specially constructed machine designed to simulate the brushing of interproximal plaque between mandibular molar teeth; the bristles of the toothbrush did not make contact with the biofilm at any time. The load force between the brushes and teeth were in accordance with typical use and an exposure time of 5 seconds was used throughout. The efficacy of brushing was assessed by enumeration of the percentage of viable bacteria removed from the HA discs. These experiments were conducted with the electronic effect of the toothbrushes either activated or inactivated.Activation of toothbrush A significantly (P = 0.004) increased the median percentage of bacteria removed from 0.47% to 48.45%. Likewise, activation of toothbrush B significantly (P = 0.015) increased the median percentage of bacteria removed from 2.85% to 15.86%. The median percentage of plaque bacteria removed by the active toothbrush A was significantly (P = 0.009) greater than that removed by toothbrush B in this model system.These data imply that toothbrush A would be more effective than toothbrush B at removing interproximal dental plaque in vivo.

Bacterial biofilms have been reported to contain distinct regions of viable and nonviable bacteria. The purpose of this study was to identify such regions in biofilms of oral bacteria and to determine their dimensions. Oral biofilms were grown aerobically in a constant-depth film fermenter (CDFF) and studied using confocal laser scanning microscopy (CLSM) incorporating viability staining with water immersion lenses. A variety of viability distributions were observed, including biofilm "stacks" possessing an outer layer of viable bacteria surrounding an internal core of nonviable bacteria. Using image analysis tools, we measured the thickness of this outer viable region, in the x-y plane, from single confocal optical sections, and determined the mean angle (theta) of these portions of the biofilm stack (10.93 degrees ). x-y plane thickness data in conjunction with the data on the angle of the stack returned the thickness of the outer viable layer perpendicular to the bulk medium flow as 36.62 microm (31.61-42.21 microm accounting for 95% confidence for variation in both the x-y plane thickness and theta). We have shown that CLSM, in conjunction with vital stains and image analysis techniques, can reveal viability patterns in biofilms and where appropriate can be used to measure the dimensions of these structures.

To determine the plaque-removing ability of a Sonicare Plus electric toothbrush in an in vitro model.Multispecies oral biofilms derived from human saliva were grown on hydroxyapatite discs in a constant-depth film fermenter. The biofilms were placed in a typodont model so that they mimicked the interproximal plaque between teeth 46 and 47 and were then treated with an electric toothbrush, both activated and inactivated. The distance from the bristle tips to the edge of the disc was 2.65 mm. Brushing action was controlled by a specially constructed brushing machine. After brushing, the number of viable bacteria removed from, and remaining in, the biofilms were determined.In all, 73.70% of viable bacteria in the biofilms were dislodged from the discs using the activated toothbrush. An inactivated toothbrush removed only 3.66%. Scanning electron microscopy and confocal microscopy revealed differences between untreated and treated biofilms.The fluid shear forces generated by the electric toothbrush penetrated at least 2.65 mm beyond the reach of the bristles and these forces contributed to the toothbrush's plaque-removal ability (p0.001).

To compare the efficacy of interproximal plaque removal beyond the bristles by two electric toothbrushes, the new Sonicare Elite and Braun Oral-B 3D, in an in vitro model replicating the brushing of interproximal plaque as would occur in vivo.Oral biofilms were grown, in vitro, in a constant-depth film fermenter on a hydroxyapatite (HA) disc substratum. Brushing experiments were conducted in a brushing machine representing the brushing of interproximal plaque between mandibular molars. The HA discs with oral biofilms were located a minimum of 1.6 mm away from the bristles. The efficacy of plaque removal was assessed by enumeration of the percentage of viable bacteria removed from the biofilms by 5 seconds of brushing with the brush motors either activated or inactivated.In the activated state, both brushes removed a significantly higher percentage of plaque bacteria compared to the inactive brushes (Braun, P = 0.002; Sonicare, P = 0.005). The percentage of plaque bacteria removed by the Sonicare Elite (32.23%) beyond the bristles was significantly greater (P = 0.012) than that removed by the Braun Oral-B 3D (9.48%) in this model system.

The aim of the present study was to assess the use of an echo-enhancing agent (Levovist; Schering AG) in equivocal carotid bifurcation ultrasound studies and compare the information obtained with digital subtraction angiography (DSA). Contrast-enhanced carotid ultrasound studies were performed on 30 carotid bifurcations in 28 patients. The standard carotid ultrasound examinations were considered equivocal for two reasons: apparent acute internal carotid artery occlusions (n = 10), and possibly patent but critically stenosed internal carotid arteries with the residual flow lumen being incompletely visualized (n = 20). All patients underwent subsequent carotid digital subtraction angiography. All patients with apparent acute carotid occlusions (n = 10) were correctly characterized on contrast-enhanced ultrasound when compared with DSA. The majority were complete occlusions (n = 8) although in two cases there were critical carotid stenoses requiring surgical endarterectomy. In the 'incompletely visualized lumen' group (n = 20), the majority (n = 16) were correctly characterized on contrast enhanced ultrasound: 13 cases of critically stenotic but patent internal carotid arteries, two cases without a haemodynamically significant stenosis and one case of a carotid occlusion with patent vasa vasorum. One of the critical carotid stenoses was prospectively reported as occluded on the 'gold standard' angiography. In three cases the flow lumen was still incompletely visualized due to calcified plaque despite an echo-enhancing agent; angiography revealed no significant stenosis in all cases. There was one false negative for internal carotid occlusion. This occurred early in the series and could be considered to be a technical error. Importantly, there were no false positives for carotid occlusion. Contrast-enhanced carotid ultrasound significantly improves diagnostic confidence in equivocal carotid ultrasound studies. In appropriate clinical settings this may reduce the need for subsequent carotid angiography.

BACKGROUND AND PURPOSE: Coil embolization of berry aneurysms is a relatively new treatment whose long-term efficacy has yet to be established. The purpose of this study was, first, to attempt to identify factors that might be important in predicting success both at the time of treatment and at the time of follow-up angiography, and, second, to study changes in the aneurysm between treatment and follow-up to determine the frequency of these changes. METHODS: The pretreatment, posttreatment, and follow-up angiograms of the first 63 aneurysms (in 58 patients) treated at our institution between June 1992 and April 1995 were analyzed, and the percentage of occlusion of each aneurysm was calculated. The size of any rest was noted for the posttreatment and follow-up angiograms. Treatment success was defined as a residue of less than 2 mm. Aneurysms were said to have changed if the percentage of occlusion had altered by more than 2.5% or if the difference in rest size was greater than 0.25 mm. Possible factors influencing primary and follow-up success rates were correlated against these calculations. RESULTS: Success rates at treatment and follow-up were 71% and 65%, respectively. No change occurred in 41% of aneurysms, and 20% had a decrease in size of the residue. Twenty-eight percent had coil compaction, and 11% had aneurysmal growth. Neck size was the only significant variable in primary treatment success. Success at follow-up correlated significantly with neck size, initial treatment success, vasospasm at the time of treatment, and clinical presentation. CONCLUSION: Best long-term angiographic results are obtained when the primary treatment is successful, when the aneurysm is small and narrow-necked, when the acutely ruptured aneurysm is treated within 15 days of ictus, and with anterior communicating and basilar-tip aneurysms.

This study explores the perceptions of, and outcomes for, a group of undergraduate mental health nursing students over a 3-year period from the point at which they made their choice to take the mental health branch of a 4-year degree programme in nursing, to working in the practice setting as registered nurses. Semi-structured interviews were completed at three points in their career: (a) at the end of the common foundation programme, when students had made their choice to take the mental health option; (b) at the end of the fourth year of the undergraduate programme; and (c) 1 year post-qualification. Questions were generated around five main themes: career choice, personal change and development, evaluation of the curriculum, ideas about mental health nursing and career plans. Despite some initial ambivalence at the start of the branch, students were happy with their career choice at follow-up, which was reinforced by significant clinical progress. All of the group were working in acute hospital settings despite being in possession of the community mental health qualification. Substantial evidence of these students' 'fitness for purpose' is offered, although some disillusionment with the contrast between student life and the real world of work is noted. Questions are posed as to the role of clinical supervision and education in preventing negative professional socialization. Recommendations are also made about recruitment to and design of mental health nursing courses.

Twitch contractions of the ankle dorsiflexors were evoked before and after 7 s of tetanic stimulation at 100 Hz in young women and men. Torque decreased more in men (18%) than in women (12%) during the tetanus. There was no gender difference in twitch peak torque potentiation over the 5-min post-tetanus. Potentiation was 42% (women) and 45% (men) at 5 s post-tetanus, and still present at 5 min (women 24%, men 25%). The immediate (5 s) shortening of twitch rise time was similar in women (14%) and men (13%), but during the 5-min men's rise time came to exceed whereas women's only approached pretetanus values (e.g., +9% vs. -1% at 5 min). The immediate decrease in half-relaxation time was also similar in women (24%) and men (22%); however, women's but not men's values remained less than pretetanus values for most of the 5-min period. Twitch rate of torque development increased similarly (75%) in women and men at 5 s, with no gender difference over 5 min. In contrast, rate of torque relaxation increased significantly only in men. Rate of torque development normalized to peak torque was similar in women and men pretetanus and increased similarly 5 s post-tetanus, but women had greater values through most of the 5-min post-tetanus. Normalized rate of torque relaxation was similar in women and men and not affected by tetanus. In the dorsiflexor muscles, young women and men show a similar amount and pattern of twitch force potentiation, but there are gender differences in time-related twitch contractile properties in the first 5 min after tetanus.

An organizational dynamics paradigm is examined for effectiveness in predicting absenteeism among staff RNs in four hospitals. Different predictor variables were important within each hospital. Discussion is focused on the manager role and organizational policies related to criteria for excessive absence, incentives for attendance, and deterrents to absence.

Fish advisories are important tools in public health practice and are primarily used to translate fish contaminant levels into consumption recommendations for consumers. Even when a targeted advisory is issued, it may alter broad food consumption patterns among the public, including diminishing intake of fish-based protein and polyunsaturated fatty acids. Such alterations may have both positive (e.g., reduced exposure to contaminants) and negative (e.g., loss of health benefits or cultural traditions associated with consuming fish) consequences. Currently, a fish advisory may be based on the potential for either noncarcinogenic or carcinogenic endpoints. Consumption recommendations based on a cancer outcome are likely to be highly restrictive, potentially diminishing opportunities for the recognized health benefits associated with a fish-rich diet. This possibility causes us to raise 3 arguments against using cancer risk as the basis for fish consumption advisories. First, the benefits of fish consumption are widely recognized. Second, the standard methodology to predict cancer risk is likely to overestimate actual risk, often by orders of magnitude. Third, the public's real and perceived concerns about cancer may result in unintended consequences, such as avoidance of fish altogether. As an alternative to cancer-based advisories, we suggest that future advisories incorporate a multidisciplinary public health framework focused on avoiding noncarcinogenic health outcomes and encouraging the public to consume a balanced diet rich in fish. We also suggest that decision makers need to 1) understand which elements of the advisory process are science and which are implicit or default policy, 2) consciously consider whether these policy elements are appropriate for their particular situation, and 3) if not, be willing to make and defend alternative policy choices.

The nature of aggression or hostility is discussed, and the possible relations between hostility in the personalities of husbands and hostility in the personalities of wives are conceptualized under the heads: (a) Similarity in quantity of aggression; (b) Similarity in pattern of aggression; (c) Oppositeness or complementarity in quantity of aggression; (d) Oppositeness or complementarity in pattern of aggression; and (e) Systematic relations between similar or dissimilar (but not necessarily opposite) patterns of aggression. The first four possibilities are explored by imposing a model on questionnaire data obtained from alcoholics and their wives. The fifth possibility, which is the first to be dealt with, is investigated with the aid of a technique which follows the pattern of the data without imposing a model on them. The analysis demonstrates that exclusive reliance on correlational methods, however complex, may obscure the essential features of a psychological situation. It also shows how the special characteristics of temperamental qualities may be accommodated by the construction of an appropriate model.

This report is the first of a series investigating aspects of cognitive disorder in schizophrenia, and deals with the validity of some tests as measures of thought-process disorder ("formal thought disorder") and with the relations between the tests. A battery of tests, including the Object Classification, modified Proverbs, and Bannister-Fransella tests, was administered to a group of schizophrenics with active psychotic symptoms, selected so that there were equal numbers of acute and chronic, paranoid and non-paranoid, and male and female patients. A psychiatric rating of degree of thought-process disorder was made. The main results were: 1. The Bannister-Fransella measures of Intensity and Consistency are significantly and positively correlated among Acute Schizophrenics, but not among Chronics. 2. The Payne-Hewlett measures of "Non-A" responses and Proverbs are positively, but not significantly, correlated among both Acutes and Chronics. The present evidence supports the view that they should not be combined. 3. Seven of the eight correlations between Bannister-Fransella and Payne-Hewlett measures are negative, though non-significant. 4. Consistency is significantly related to a psychiatrist's rating of thought-process disorder in the expected direction among Acute, but not among Chronic, Schizophrenics. The measure has, therefore, been validated against this new criterion for Acute but not for Chronic Schizophrenics. The pattern is similar for Intensity, though the validity coefficient for acutes is not significant. 5. "Non-A" responses are heterogeneous, mostly unrelated to the usual meaning of "over-inclusion", and negatively related to the rating of thought-process disorder among Acutes and insignificantly among Chronics. The number of words used to define Proverbs is negatively, and almost significantly, related to rated thought-process disorder among Acutes. The positive relation among Chronics is small and non-significant.

A group of males with XYY sex-chromosome complement was compared with a matched group of fellow-patients in a state mental hospital. There were very few significant differences between mean scores of the two groups on psychological tests. There were, however, differences in the inter-relations of tests. There was a marked discrepancy between the two groups in the effect of response set (defensiveness) on replies to questionnaires. A difference in the structure of aggression or hostility was also detected. If response set is indeed an important determinant of psychological test scores, and if its mode of action differs in XYY patients and in comparable non-XYY patients, then any obtained mean differences (or similarities) are suspect. The importance of this caveat becomes even more evident when we consider that the unco-operative patients who had to be omitted from the testing were probably high defenders. Perhaps the most direct approach to eliciting the psychological peculiarities of XYY patients would be to find out what it is that the high defenders among them do not wish to admit. The patient's and the psychologist's perceptions of the purpose of a particular test item are often quite disparate. The next stage of the enquiry is to ask what the patient thought he would be admitting if in fact he had not exercised defensiveness in a particular response.

The Maudsley Personality Inventory (MPI) E scale is validated by a direct method which has not hitherto been employed. It is shown that, in a neurotic sample, it measures a dimension of personality which has been called the hysteroid-obsessoid dimension and is unrelated to type of illness.

A psychotic v. neurotic scale has been presented in the manual of the Symptom-Sign Inventory (Foulds and Hope, 1968). This scale was constructed after comparing each of four female neurotic groups with each of four female psychotic groups and each of four male neurotic groups with each of four male psychotic groups. For an item to be included in the scale 14 of the 16 comparisons within each sex had to show differences significant at least at the 5 per cent. level. On 18 items the psychotic groups had frequencies in excess of the neurotic; on only one item was it the other way round. The scale score is the sum of these 18 items minus the one.

The aim of this paper is to describe the Body Awareness Group Therapy (BAGT) designed for patients with personality disorders. The BAGT is a body-oriented small group therapy conducted by a physiotherapist and a cotherapist. The aim is to foster personal growth and development by use of individual and group exercises. The therapy is a synthesis of earlier clinical experiences, mostly based on works of Reich, on elements of encounter and of eastern body tradition.

Meningeal tumors occurring in a pediatric hospital over a period of 18 years were studied. The incidence of meningeal sarcomas was much lower than has been previously reported. A histologic subtype of meningiomas was found which has not previously been described. In these "sclerosing" tumors only a small portion of the lesion contained viable cells, most of which bore little resemblance to conventional meningothelial cells. The bulk of the lesions consisted of whorling collagen bundles produced by the tumor. All cases in which there was tumor invasion of the brain fell into this category. The prognosis for the sclerosing meningiomas was similar to conventional meningiomas, casting doubt on the value of brain invasion as a marker of malignancy in childhood meningiomas. The recognition of this histologic type may aid diagnosis, guide surgical management, and possibly make postoperative radiotherapy unnecessary.