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BACKGROUND: Stigma reduction has been identified as a key public health strategy to increase enrollment in behavioral health services. As our understanding about stigma reduction has become more sophisticated, there has been an increased recognition that efforts to reduce stigma must engage the complex relationships between stigma, literacy, and contact with others who have a behavioral health condition. AIMS: The goal of this project was to improve understanding about the relationships between behavioral health literacy, stigma, and contact to inform efforts to increase public behavioral health literacy and decrease stigma. Specifically, this project explored how the structure of these relationships varied for different substance use and mental health conditions. METHOD: Structural equation modeling was used to depict relationships with data from a nationally-representative survey on behavioral health literacy and stigma. RESULTS: The impact of prior contact and literacy on stigma varied by behavioral health condition. CONCLUSIONS: Stigma reduction efforts will be most successful when they match the level of literacy and prior contact with the condition among the target audience for stigma reduction efforts.

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The rapid emergence of drug resistance, unfavourable immunosuppression and mounting evidence to suggest the deleterious accumulation of drug breakdown residues within animal tissues has driven a strong desire to move away from these current methods of disease control. Some natural products such as ß-glucan, which are extracted from, for example, plants and fungi, are able to modulate the immune system and increase protection against diseases. However, these products are heterogeneous and their effects can be variable thus limiting their applicability and reliability. Carbohydrates were modified via chemical sulphation and these semi-synthetic, sulphated carbohydrates analysed for their immunological activity utilising carp pronephric cells and a carp leucocyte cell line (CLC). A sulphated ß(1,4)-glucan, methyl hydroxyethyl cellulose sulphate (MHCS), demonstrated a stimulatory effect on fish immune cells. MHCS induced a range of bioactive effects in carp leucocyte cells whilst not affecting cell viability when cells were exposed for 24 h at concentrations of 1-150 µgml-1. MHCS stimulated the innate immune system where a significant increase in respiratory burst activity was observed at concentrations 25-250 µgml-1 in comparison to control (sterile water), cellulose ether, MacroGard® and zymosan. Also, under in mock bacterial and viral infection conditions i.e. Lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (Poly(I:C)), MHCS enhanced the immune responses of pronephric cells by stimulating the respiratory burst activity at concentrations 50 and 150 µgml-1. MHCS also enhanced the expression of cytokines including interleukin 1 beta (IL1ß), tumor necrosis factor alpha 1 and 2 (TNFα 1,2), interferons alpha 2 (IFN α2) and inducible nitric oxide synthase (iNOS) in carp pronephric cells. It is proposed that this new semi-synthetic carbohydrate is a potential candidate for the development of a new generation of immunostimulants and adjuvants for use in vaccination strategies in aquaculture.

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Prophylactic internal fixation (PIF), with a bone plate in either the anterior (over the section defect) or posterior (on intact cortex) position, has substantially reduced the incidence of fracture at the donor site of the radial osteocutaneous free flap. This study uses the sheep tibia model to compare the effectiveness of new T-shaped titanium plates utilising a unilocking screw system with a 3.5 mm steel plate and bicortical screw fixation system commonly applied for PIF. Forty matched pairs of adult sheep tibias were tested in torsion and 4-point bending. An osteotomised bone was significantly weaker (p<0.001) than an intact bone in both bending and torsion with a mean loss of 77% and 64% of strength respectively. The tibia withstood much greater bending loads. All of the constructs significantly strengthened an osteotomised bone by a factor of 1.73-2.43 times in bending and 1.54-2.63 in torsion. The 2.4 mm T-plate in an anterior position (section) was the baseline against which other plates in differing positions were compared. The 3.5 mm T-plate section, DCP section and DCP cortex constructs had 41%, 30% and 2% greater mean bending strengths respectively but only the 3.5 mm T-plate section result approached statistical significance (p=0.06). In torsion the DCP section, 3.5 mm T-plate section and DCP cortex constructs had 56% (p=0.01), 27% (p=0.06) and 25% greater mean strengths respectively. When compared to an intact bone the mean bending strength restored by the DCP section (84%) and 3.5 mm T-plate section (87%) constructs was greatest and effectively restored the strength to that of an intact bone (100%). In torsion the mean strength restored by the DCP section (62%), DCP cortex (44%), 3.5 mm T-plate section (40%) and 2.4 mm T-plate (36%) remained significantly less than an intact bone. All of the plate constructs significantly strengthened an osteotomised bone but overall the 3.5 mm T-plate section and DCP section were the strongest constructs and most suitable for PIF. The lighter 2.4 mm T-shaped titanium plate was least effective. The strongest reinforcement in bending and torsion was the 3.5 mm T-plate section and DCP section respectively. The 3.5 mm DCP section plate was significantly stronger (p=0.01) than the 3.5 mm T-plate in torsion and remains the most effective construct for resisting torsional stresses, which are probably the commonest cause of fracture in clinical practice.

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OBJECTIVE: To study trainee and supervisor perspectives for success or failure of conversion of abstracts to full manuscripts. STUDY DESIGN: Abstracts presented by trainees between 2000 and 2005 were identified from the syllabi of the Paediatric Academic Society, Canadian Paediatric Society and Hot Topics meetings. The trainee and senior supervisor for each abstract were asked to complete a web-based survey that explored enablers and disablers. RESULT: Of the 187 abstracts identified, 62 (33%) had trainees as primary authors. Of these, the responses of 42 (68%) trainees and 50 (81%) supervisors were collected; the responses of 21 (50%) trainees and 19 (38%) supervisors reported success in converting the abstract to a manuscript. According to trainees, good research idea, supportive supervisors and practical design were the main enablers, whereas limited time for research and the limited data collection only for abstracts were the main disablers. According to supervisors, adequate research time and the trainees' interest were the main enablers, whereas limited data collection and lack of trainees' interest were the main disablers. Specified research training, allocation of protected research time and making publication mandatory were suggested by both to enhance publication rate. CONCLUSION: Training programs should consider research training needs and provide dedicated time to improve research productivity by trainees.

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The glycosaminoglycan (GAG) family of linear sulphated polysaccharides are involved in most regulatory processes in the extracellular matrix of higher organisms. The relationship between GAG substitution pattern and activity, however, remains unclear and experimental evidence suggests that subtle conformational factors play an important role. The difficulty of modelling these complex charged molecules shifts the burden of investigation towards experimental techniques. Recent advances in complementary physical-chemical, particularly spectroscopy-based approaches are reviewed, together with methods for analysing the resulting complex data. The prospects for combining some of these approaches and fitting them into the wider context of interactions, are also discussed.

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The interactions between Cu(II) ions and heparin were investigated using several complementary spectroscopic techniques. NMR indicated an initial binding phase involving specific coordination to four points in the structure that recur in slightly different environments throughout the heparin chain; the carboxylic acid group and the ring oxygen of iduronate-2-O-sulfate, the glycosidic oxygen between this residue and the adjacent (towards the reducing end) glucosamine and the 6-O-sulfate group. In contrast, the later binding phase showed little structural specificity. One- and two-dimensional correlated FTIR revealed that complex out of phase (asynchronous) conformational changes also occurred during the titration of Cu(II) ions into heparin, involving the CO and N-H stretches. EPR demonstrated that the environments of the Cu(II) ions in the initial binding phase were tetragonal (with slightly varied geometry), while the later non-specific phases exhibited conventional coordination. Visible spectroscopy confirmed a shift of the absorbance maximum. Titration of Cu(II) ions into a solution of heparin indicated (both by analysis of FTIR and EPR spectra) that the initial binding phase was complete by 15-20 Cu(II) ions per chain; thereafter the ions bound in the non-specific mode. Hetero-correlation spectroscopy (FTIR-CD) improved resolution and assisted assignment of the broad CD features from the FTIR spectra and indicated both in-phase and more complex out of phase (synchronous and asynchronous, respectively) changes in interactions within the heparin molecule during the titration of Cu(II) ions.

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Eight Delta-disaccharide standards from heparan sulfate/heparin were derivatized with the fluorophore 4,4-difluoro-5,7- dimethyl-4-bora-3a,4a-diaza-s-indacene-3-propionic acid, hydrazide (BODIPY) via formation of a Schiff's base and separated using HPAEC on a Propac PA1 column with a linear salt gradient and isocratic 150 mM NaOH. Detection was with an in-line fluorescence detector. The standard deviation (sigma(n-1)) in retention times were 0.7-2% over nine runs. The limit of detection, was 100 fmol (100 x 10(-15)mol) of BODIPY labeled Delta-disaccharides, representing considerably improved detection compared to other fluorophore labeled derivatives and, unlike these, required no further purification steps. Separation and improved detection of BODIPY-Delta-disaccharide conjugates will assist the structural analysis of HS and the development of improved sequencing methodologies.

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New approaches, rooted in the physical sciences, have been developed to gain a more fundamental understanding of protein-GAG (glycosaminoglycan) interactions. DPI (dual polarization interferometry) is an optical technique, which measures real-time changes in the mass of molecules bound at a surface and the geometry of the bound molecules. QCM-D (quartz crystal microbalance-dissipation), an acoustic technique, measures the mass and the viscoelastic properties of adsorbates. The FTIR (Fourier-transform IR) amide bands I, II and III, resulting from the peptide bond, provide insight into protein secondary structure. Synchrotron radiation CD goes to much shorter wavelengths than laboratory CD, allowing access to chromophores that provide insights into the conformation of the GAG chain and of beta-strand structures of proteins. To tackle the diversity of GAG structure, we are developing noble metal nanoparticle probes, which can be detected at the level of single particles and so enable single molecule biochemistry and analytical chemistry. These new approaches are enabling new insights into structure-function relationships in GAGs and together they will resolve many of the outstanding problems in this field.

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Volatilisation of crop protection chemicals from soil and crop surfaces is one of a number of processes that may contribute to their dissipation in the environment. Therefore, information on the potential of a chemical to volatilise from these surfaces is required by international and national registration authorities. This paper reports the results of more than 190 experiments, which were carried out with 80 different crop protection chemicals under controlled conditions (laboratory and/or greenhouse) according to the BBA guideline. Percent loss values observed during 24 h after application are reported for 123 soil and 71 crop volatility studies. Generally, volatile losses from crop surfaces were found to be greater than from soil surfaces under comparable experimental conditions. It has been previously proposed that volatile losses from soil surfaces, from crops, and from aqueous systems can be estimated from physico-chemical parameters. The data are therefore analysed to determine whether a correlation exists between volatilisation and physico-chemical parameters, such as vapour pressure, Henry's law constant, water/air and soil/air distribution coefficients. It was found that these parameters can be used to make reasonable predictions of volatile losses from crop and soil surfaces, which can be expected for crop protection chemicals under controlled conditions. Vapour pressure was the best predictor of losses from soil and crops. The use of the soil/air distribution coefficient is an alternative for predicting/estimating the volatility potential of a chemical from soil. Based on direct measurements, no noticeable volatility can be expected from compounds with a vapour pressure below 10(-3) Pa from soil and 10(-4) Pa from crops, this is fully confirmed by indirect measurements. A tiered volatility testing scheme including appropriate trigger values is proposed.

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OBJECTIVES: To evaluate the impact of a neonatal resuscitation course on the theoretical knowledge and practical skills of birthing room personnel, and to evaluate the performance of skills at different times after the course. DESIGN: A program evaluation using a before and after cohort study. SETTING: Seven level II perinatal centres in the central-east region of Ontario. PARTICIPANTS: Seven hundred thirty-seven individuals (medical staff, nurses and respiratory technologists) who worked in birthing rooms. INTERVENTION: During an eight-month period, a course in neonatal resuscitation was presented at the perinatal centres. A cohort of 108 (15%) participants received testing before and after the course; the theoretical knowledge and practical performance of 62 of these participants were retested after six and 12 months. RESULTS: A significant improvement in both theoretical knowledge and practical skills was seen immediately after the course. Throughout the study, no difference was observed in the performance of nursing staff compared with that of medical staff, nor among the institutions involved. No significant difference in the decline of either theoretical knowledge or practical skills was seen among those who scored well in the original pre-test compared with those who scored poorly. CONCLUSIONS: Neonatal resuscitation should be an integral part of continuing education for all personnel involved in obstetrical care because it improves both tested knowledge and performance. Practical skills appear to decline faster than theoretical knowledge. Inservice instruction is required, at least, every six months.

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The debris-rich basal ice layers of a high Arctic glacier were shown to contain metabolically diverse microbes that could be cultured oligotrophically at low temperatures (0.3 to 4 degrees C). These organisms included aerobic chemoheterotrophs and anaerobic nitrate reducers, sulfate reducers, and methanogens. Colonies purified from subglacial samples at 4 degrees C appeared to be predominantly psychrophilic. Aerobic chemoheterotrophs were metabolically active in unfrozen basal sediments when they were cultured at 0.3 degrees C in the dark (to simulate nearly in situ conditions), producing (14)CO(2) from radiolabeled sodium acetate with minimal organic amendment (> or =38 microM C). In contrast, no activity was observed when samples were cultured at subfreezing temperatures (< or =-1.8 degrees C) for 66 days. Electron microscopy of thawed basal ice samples revealed various cell morphologies, including dividing cells. This suggests that the subglacial environment beneath a polythermal glacier provides a viable habitat for life and that microbes may be widespread where the basal ice is temperate and water is present at the base of the glacier and where organic carbon from glacially overridden soils is present. Our observations raise the possibility that in situ microbial production of CO(2) and CH(4) beneath ice masses (e.g., the Northern Hemisphere ice sheets) is an important factor in carbon cycling during glacial periods. Moreover, this terrestrial environment may provide a model for viable habitats for life on Mars, since similar conditions may exist or may have existed in the basal sediments beneath the Martian north polar ice cap.

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OBJECTIVE: To study short- and long-term outcomes of infants < or = 750 g birthweight who received cardiopulmonary resuscitation (CPR) in the delivery room. METHODOLOGY: A retrospective analysis of all inborn live births < or = 750 g birthweight from 1990 to 1996. Cardiopulmonary resuscitation was defined as positive pressure ventilation via an endotracheal tube and chest compressions. Univeriate analysis were conducted comparing patients according to the use of CPR or positive pressure ventilation alone. RESULTS: Cardiopulmonary resuscitation was administered to 16 infants: four received chest compressions only and 12 also received adrenaline. Cardiopulmonary resuscitation recipients had significantly lower Apgar scores at both 1 and 5 min, and had delayed onset of spontaneous respiration (P < 0.01). Seven patients died, and eight of nine survivors were free of major neurodevelopmental abnormalities at follow up. All CPR recipients with a 5 min Apgar score of < or = 5 and delayed onset of spontaneous respiration beyond 5 min had poor outcomes. CONCLUSION: Contrary to the majority of published evidence, delivery room CPR in our extremely small infants was not associated with a high risk of severe neurodevelopmental disability.

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The mission hardware provided for Bion 11 shared primate experiments included the launch vehicle, biosatellite, spaceflight operational systems, spacecraft recovery systems, life support systems, bioinstrumentation, and data collection systems. Under the unique Russia/US bilateral contract, the sides worked together to ensure the reliability and quality of hardware supporting the primate experiments. Parameters recorded inflight covered biophysical, biochemical, biopotential, environmental, and system operational status.

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A summary is provided of the major operations required to conduct the wide range of primate experiments on the Bion 11 mission, which flew for 14 days beginning December 24, 1996. Information is given on preflight preparations, including flight candidate selection and training; attachment and implantation of bioinstrumentation; flight and ground experiment designs; onboard life support and test systems; ground and flight health monitoring; flight monkey selection and transport to the launch site; inflight procedures and data collection; postflight examinations and experiments; and assessment of results.

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The A alpha subunit of human protein phosphatase 2A forms crystals in space group P2(1) with cell dimensions a = 104.0, b = 174.9, c = 168.2 A, and beta angle = 90.2 degrees. At cryogenic temperatures, the crystals diffracted to a resolution limit of approximately 3.0 A. Based on the unit cell dimensions and a calculated molecular mass of 65,277 Da, the Matthews coefficient suggests eight molecules per asymmetric unit. Two native data sets were collected to a nominal resolution of 3.0 A and merged to provide a set that is 93% complete, with Rsym of 9.9%.

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Four newborn infants with Down syndrome and manifestations of neonatal leukemia are described. One of the four was stillborn, two died shortly after birth, and a fourth survived and all evidence of leukemia disappeared in the first month of life. Three of the four cases had hydrops fetalis, and a fourth was a macerated stillborn. Nine other similar reported cases are reviewed. We conclude that neonatal leukemia in Down syndrome is a form of leukemia that is usually transient, with spontaneous recovery, but may be fatal at or around the time of birth with manifestations of hydrops fetalis, hepatosplenomegaly, and/or progressive liver disease.

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To examine whether cleavage of the phi X174 prohead accessory protein, gpB, by the OmpT protease is required for phage development in vivo, a phage mutant lacking the OmpT cleavage site and an Escherichia coli C delta ompT strain were constructed. The results of burst size experiments suggest that neither the cleavage site nor the OmpT protein is required for phi X174 development.

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A headward fluid shift occurs in humans exposed to space-flight. This shift is thought to be the stimulus for the observed reduction in plasma volume, and may produce a sustained rise in intracranial pressure (ICP). In order to determine the effect of head-down tilt (HDT) and water immersion on intracranial pressure (ICP), five anesthetized rhesus monkeys were fitted with intracranial pressure-monitoring transducers and subjected to -6 degrees HDT followed by head-out thermoneutral (34.7 degrees) water immersion. ICP was elevated from 3.8 +/- 1.1 mm Hg in the horizontal control period to 5.3 +/- 1.3 mm Hg (p less than 0.05) during the 15 min pre-immersion HDT. When seated in the empty immersion tank, ICP stabilized at -6.3 +/- 1.3 mm Hg for the control period and increased to -2.2 +/- 1.9 mm Hg (p less than 0.05) when the water level was maintained for 30 min at the sternal notch. The ICP returned toward pre-immersion levels (-5.5 +/- 1.4 mm Hg) as the tank was drained. Mean blood pressure (MBP) remained constant during the pre-immersion tilt test. In the pre-immersion control period, MBP was 91 +/- 3 mm Hg compared to 90 +/- 4 mm Hg (p greater than 0.05) during immersion and 82 +/- 1 mm Hg (p less than 0.05) in the post-immersion recovery period. In summary, exposure of rhesus monkeys to either head-down tilt or water immersion produced a prompt rise in ICP during the stimulus period.(ABSTRACT TRUNCATED AT 250 WORDS)

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The U.S. Army's two-phase program for training nurse anesthetists came about in response to the demand for nurse anesthetists to serve in Vietnam. It fostered a move toward nurse anesthesia education at the master's degree level and upgraded the requirements for attaining such a degree.

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