Identifying the barriers and enablers in the implementation of the New Zealand and Australian Antenatal Corticosteroid Clinical Practice Guidelines

Background

The ineffective implementation of evidence based practice guidelines can mean that the best health outcomes are not achieved. This study examined the barriers and enablers to the uptake and implementation of the new bi-national (Australia and New Zealand) antenatal corticosteroid clinical practice guidelines among health professionals, using the Theoretical Domains Framework.

Methods

Semi-structured interviews or online questionnaires were conducted across four health professional groups and three district health boards in Auckland, New Zealand. The questions were constructed to reflect the 14 behavioural domains from the Theoretical Domains Framework. Relevant domains were identified by the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on the behaviour using thematic analysis. The influence of health professional group and organisation on the different barriers and enablers identified were explored.

Results

Seventy-three health professionals completed either a semi-structured interview (n = 35) or on-line questionnaire (n = 38). Seven behavioural domains were identified as overarching enablers: belief about consequences; knowledge; social influences; environmental context and resource; belief about capabilities; social professional role and identity; and behavioural regulation. Five behavioural domains were identified as overarching barriers: environmental context and resources; knowledge; social influences; belief about consequences; and social professional role and identity. Differences in beliefs between individual health professional groups were identified within the domains: belief about consequences; social professional role and identity; and emotion. Organisational differences were identified within the domains: belief about consequences; social influences; and belief about capabilities.

Conclusion

This study has identified some of the enablers and barriers to implementation of the New Zealand and Australian Antenatal Corticosteroid Clinical Practice Guidelines using the validated Theoretical Domains Framework, as perceived by health professionals. We have identified differences between individual health professional groups and organisations. The identification of these behavioural determinants can be used to enhance an implementation strategy, assist in the design of interventions to achieve improved implementation and facilitate process evaluations to understand why or how change interventions are effective.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-016-1858-8) contains supplementary material, which is available to authorized users.

Consumers attitudes and beliefs towards the receipt of antenatal corticosteroids and use of clinical practice guidelines

BACKGROUND

Active participation of consumers in health care decision making, policy and clinical research is increasingly encouraged by governments, influential bodies and funders. Identifying the best way to achieve this is difficult due to the paucity of evidence. Consumers have mixed feelings towards clinical practice guidelines (CPG) demonstrating scepticism towards their purpose and applicability to their needs. There is no information pertaining to consumers' views and attitudes on the receipt of antenatal corticosteroids (ACS). The aim of this study was to examine the barriers and enablers to receiving ACS and use of CPG amongst consumers.

METHODS

Consumers were recruited from neonatal units across three district health boards (DHBs) in Auckland, New Zealand. Participants completed a semi-structured interview or questionnaire. The questions posed and analyses were informed by the Theoretical Domains Framework (TDF). Barriers and enablers were identified by the presence of conflicting beliefs within a domain; the frequency of beliefs; and the likely strength of the impact of a belief on use of CPG and receipt of ACS.

RESULTS

Twenty four consumers participated in the study. Six domains were identified as barriers to receipt of ACS and use of CPG. Key barriers to receipt of ACS included: difficulty retaining information conveyed, requiring further information in a variety of formats, and time constraints faced by consumers and health professionals in the provision and understanding of information to facilitate decision making. Barriers to use of CPG included: uncertainty about applicability of guideline use among consumers and scepticism about health professionals adhering too rigidly to guidelines. Enablers to receipt of ACS included: optimism toward ACS use, a strong knowledge of why ACS were administered, improved resilience in their pregnancy and confidence in their decision making following receipt of information about ACS. Enablers to use of CPG included: validation and standardisation of decision making among health professionals providing care and facilitating the best care for women and their babies.

CONCLUSIONS

Key barriers and enablers exist among consumers regarding receipt of ACS and use of CPG. These need to be addressed or modified in any intervention strategy to facilitate implementation of the ACS CPG.

Healthy brain connectivity predicts atrophy progression in non-fluent variant of primary progressive aphasia

Neurodegeneration has been hypothesized to follow predetermined large-scale networks through the trans-synaptic spread of toxic proteins from a syndrome-specific epicentre. To date, no longitudinal neuroimaging study has tested this hypothesis in vivo in frontotemporal dementia spectrum disorders. The aim of this study was to demonstrate that longitudinal progression of atrophy in non-fluent/agrammatic variant primary progressive aphasia spreads over time from a syndrome-specific epicentre to additional regions, based on their connectivity to the epicentre in healthy control subjects. The syndrome-specific epicentre of the non-fluent/agrammatic variant of primary progressive aphasia was derived in a group of 10 mildly affected patients (clinical dementia rating equal to 0) using voxel-based morphometry. From this region, the inferior frontal gyrus (pars opercularis), we derived functional and structural connectivity maps in healthy controls (n = 30) using functional magnetic resonance imaging at rest and diffusion-weighted imaging tractography. Graph theory analysis was applied to derive functional network features. Atrophy progression was calculated using voxel-based morphometry longitudinal analysis on 34 non-fluent/agrammatic patients. Correlation analyses were performed to compare volume changes in patients with connectivity measures of the healthy functional and structural speech/language network. The default mode network was used as a control network. From the epicentre, the healthy functional connectivity network included the left supplementary motor area and the prefrontal, inferior parietal and temporal regions, which were connected through the aslant, superior longitudinal and arcuate fasciculi. Longitudinal grey and white matter changes were found in the left language-related regions and in the right inferior frontal gyrus. Functional connectivity strength in the healthy speech/language network, but not in the default network, correlated with longitudinal grey matter changes in the non-fluent/agrammatic variant of primary progressive aphasia. Graph theoretical analysis of the speech/language network showed that regions with shorter functional paths to the epicentre exhibited greater longitudinal atrophy. The network contained three modules, including a left inferior frontal gyrus/supplementary motor area, which was most strongly connected with the epicentre. The aslant tract was the white matter pathway connecting these two regions and showed the most significant correlation between fractional anisotropy and white matter longitudinal atrophy changes. This study showed that the pattern of longitudinal atrophy progression in the non-fluent/agrammatic variant of primary progressive aphasia relates to the strength of connectivity in pre-determined functional and structural large-scale speech production networks. These findings support the hypothesis that the spread of neurodegeneration occurs by following specific anatomical and functional neuronal network architectures.

Disconnection and hyper-connectivity underlie reorganization after TBI: A rodent functional connectomic analysis

While past neuroimaging methods have contributed greatly to our understanding of brain function after traumatic brain injury (TBI), resting state functional MRI (rsfMRI) connectivity methods have more recently provided a far more unbiased approach with which to monitor brain circuitry compared to task-based approaches. However, current knowledge on the physiologic underpinnings of the correlated blood oxygen level dependent signal, and how changes in functional connectivity relate to reorganizational processes that occur following injury is limited. The degree and extent of this relationship remain to be determined in order that rsfMRI methods can be fully adapted for determining the optimal timing and type of rehabilitative interventions that can be used post-TBI to achieve the best outcome. Very few rsfMRI studies exist after experimental TBI and therefore we chose to acquire rsfMRI data before and at 7, 14 and 28 days after experimental TBI using a well-known, clinically-relevant, unilateral controlled cortical impact injury (CCI) adult rat model of TBI. This model was chosen since it has widespread axonal injury, a well-defined time-course of reorganization including spine, dendrite, axonal and cortical map changes, as well as spontaneous recovery of sensorimotor function by 28 d post-injury from which to interpret alterations in functional connectivity. Data were co-registered to a parcellated rat template to generate adjacency matrices for network analysis by graph theory. Making no assumptions about direction of change, we used two-tailed statistical analysis over multiple brain regions in a data-driven approach to access global and regional changes in network topology in order to assess brain connectivity in an unbiased way. Our main hypothesis was that deficits in functional connectivity would become apparent in regions known to be structurally altered or deficient in axonal connectivity in this model. The data show the loss of functional connectivity predicted by the structural deficits, not only within the primary sensorimotor injury site and pericontused regions, but the normally connected homotopic cortex, as well as subcortical regions, all of which persisted chronically. Especially novel in this study is the unanticipated finding of widespread increases in connection strength that dwarf both the degree and extent of the functional disconnections, and which persist chronically in some sensorimotor and subcortically connected regions. Exploratory global network analysis showed changes in network parameters indicative of possible acutely increased random connectivity and temporary reductions in modularity that were matched by local increases in connectedness and increased efficiency among more weakly connected regions. The global network parameters: shortest path-length, clustering coefficient and modularity that were most affected by trauma also scaled with the severity of injury, so that the corresponding regional measures were correlated to the injury severity most notably at 7 and 14 days and especially within, but not limited to, the contralateral cortex. These changes in functional network parameters are discussed in relation to the known time-course of physiologic and anatomic data that underlie structural and functional reorganization in this experiment model of TBI.

Connected brains and minds--The UMCD repository for brain connectivity matrices

We describe the USC Multimodal Connectivity Database (http://umcd.humanconnectomeproject.org), an interactive web-based platform for brain connectivity matrix sharing and analysis. The site enables users to download connectivity matrices shared by other users, upload matrices from their own published studies, or select a specific matrix and perform a real-time graph theory-based analysis and visualization of network properties. The data shared on the site span a broad spectrum of functional and structural brain connectivity information from humans across the entire age range (fetal to age 89), representing an array of different neuropsychiatric and neurodegenerative disease populations (autism spectrum disorder, ADHD, and APOE-4 carriers). An analysis combining 7 different datasets shared on the site illustrates the diversity of the data and the potential for yielding deeper insight by assessing new connectivity matrices with respect to population-wide network properties represented in the UMCD.

Evidence of a molecular clock in the ovine ovary and the influence of photoperiod

The influence of the central circadian clock on reproductive timing is well established. Much less is known about the role of peripheral oscillators such as those in the ovary. We investigated the influence of photoperiod and timing of the LH surge on expression of circadian clock genes and genes involved in steroidogenesis in ovine ovarian stroma. Seventy-two Suffolk cross ewes were divided into two groups, and their estrous cycles were synchronized. Progestagen sponge removal was staggered by 12 hours between the groups such that expected LH peak would occur midway through either the light or dark phase of the photoperiodic cycle. Four animals from each group were killed, and their ovaries were harvested beginning 36 hours after sponge removal, at 6-hour intervals for 48 hours. Blood was sampled every 3 hours for the period 24 to 48 hours after sponge removal to detect the LH surge. The interval to peak LH did not differ between the groups (36.2 ± 1.2 and 35.6 ± 1.1 hours, respectively). There was an interaction between group and the time of sponge removal on the expression of the core clock genes ARNTL, PER1, CRY1, CLOCK, and DBP (P < 0.01, P < 0.05, P < 0.01, P < 0.01, and P < 0.01, respectively). As no significant interaction between group and time of day was detected, the datasets were combined. Statistically significant rhythmic oscillation was observed for ARNTL, CLOCK, CRY1 (P < 0.01, respectively), PTGS2, DBP, PTGER2, and CYP17A1 (P < 0.05, respectively), confirming the existence of a time-sensitive functionality within the ovary, which may influence steroidogenesis and is independent of the ovulatory cycle.

Intrinsic functional brain architecture derived from graph theoretical analysis in the human fetus

The human brain undergoes dramatic maturational changes during late stages of fetal and early postnatal life. The importance of this period to the establishment of healthy neural connectivity is apparent in the high incidence of neural injury in preterm infants, in whom untimely exposure to ex-uterine factors interrupts neural connectivity. Though the relevance of this period to human neuroscience is apparent, little is known about functional neural networks in human fetal life. Here, we apply graph theoretical analysis to examine human fetal brain connectivity. Utilizing resting state functional magnetic resonance imaging (fMRI) data from 33 healthy human fetuses, 19 to 39 weeks gestational age (GA), our analyses reveal that the human fetal brain has modular organization and modules overlap functional systems observed postnatally. Age-related differences between younger (GA <31 weeks) and older (GA≥31 weeks) fetuses demonstrate that brain modularity decreases, and connectivity of the posterior cingulate to other brain networks becomes more negative, with advancing GA. By mimicking functional principles observed postnatally, these results support early emerging capacity for information processing in the human fetal brain. Current technical limitations, as well as the potential for fetal fMRI to one day produce major discoveries about fetal origins or antecedents of neural injury or disease are discussed.

Effects of transport duration on maintenance behavior, heart rate and gastrointestinal tract temperature of market-weight pigs in 2 seasons

Welfare and meat quality of market-weight pigs may be negatively affected by transport duration and environmental temperatures, which vary considerably between seasons. This study evaluated the effects of 3 transport durations (6, 12, and 18 h) on the physiology and behavior of pigs in summer and winter in western Canada. Market-weight pigs were transported using a pot-belly trailer at an average loading density of 0.375 m(2)/100 kg. Four replicates of each transport duration were conducted during each season. Heart rate and gastrointestinal tract temperature (GTT) were monitored from loading to unloading in 16 pigs from 4 selected trailer compartments (n = 96 groups, total of 384 animals, BW = 120.8 ± 0.4 kg), namely top front (C1), top back (C4), middle front (C5), and bottom rear (C10). Behavior was recorded for pigs (948 and 924 animals, in summer and winter, respectively) in C1, C4, and C5 during transportation (standing, sitting, lying), and during 90 min in lairage (sitting, lying, drinking, latency to rest) for pigs in all 4 compartments. Transport was split into 7 periods: loading, pre-travel (PT), initial travel (IT), pre-arrival 1 (PA1) and 2 (PA2), unloading, and lairage. During IT and PA2, pigs spent less time lying in winter than summer (P < 0.05 and P < 0.05, respectively). During PA1, PA2, and unloading, a greater (P < 0.001) heart rate was found in pigs transported in winter compared with summer. During PA2, pigs subjected to the 18-h transport treatment in winter had a greater (P < 0.05) GTT than the other groups. In lairage, pigs transported for 18 h in winter drank more (P < 0.001) and took longer to rest (P < 0.01) than pigs from other groups. During PA1, pigs transported for 18 h had the greatest GTT (P < 0.001). At unloading, pigs transported for 6 h had the lowest GTT (P < 0.001). In lairage, pigs transported for 18 h spent less time lying than those transported for 6 or 12 h (P < 0.001). These results suggest that in winter, pigs increased their metabolism and were reluctant to rest on cold floors. Pigs transported for 18 h in winter showed greater evidence of thirst. It may be concluded that under western Canadian climatic conditions, long transports (18 h) in cold weather appear to be more detrimental to pig welfare.

Models of the collective behavior of proteins in cells: tubulin, actin and motor proteins

One of the most important issues of molecular biophysics is the complex and multifunctional behavior of the cell's cytoskeleton. Interiors of living cells are structurally organized by the cytoskeleton networks of filamentous protein polymers: microtubules, actin and intermediate filaments with motor proteins providing force and directionality needed for transport processes. Microtubules (MT's) take active part in material transport within the cell, constitute the most rigid elements of the cell and hence found many uses in cell motility (e.g. flagella andcilia). At present there is, however, no quantitatively predictable explanation of how these important phenomena are orchestrated at a molecular level. Moreover, microtubules have been demonstrated to self-organize leading to pattern formation. We discuss here several models which attempt to shed light on the assembly of microtubules and their interactions with motor proteins. Subsequently, an overview of actin filaments and their properties isgiven with particular emphasis on actin assembly processes. The lengths of actin filaments have been reported that were formed by spontaneous polymerization of highly purified actin monomers after labeling with rhodamine-phalloidin. The length distributions are exponential with a mean of about 7 μm. This length is independent of the initial concentration of actin monomer, an observation inconsistent with a simple nucleation-elongation mechanism. However, with the addition of physically reasonable rates of filament annealing and fragmenting, a nucleation-elongation mechanism can reproduce the observed average length of filaments in two types of experiments: (1) filaments formed from a wide range of highly purified actin monomer concentrations, and (2) filaments formed from 24 mM actin over a range of CapZ concentrations. In the final part of the paper we briefly review the stochastic models used to describe the motion of motor proteins on protein filaments. The vast majority of these models are based on ratchet potentials with the presence of thermal noise and forcing due to ATP binding and a subsequent hydrolysis. Many outstanding questions remain to be quantitatively addressed on a molecular level in order to explain the structure-to-function relationship for the key elements of the cytoskeleton discussed in this review.

The UCLA multimodal connectivity database: a web-based platform for brain connectivity matrix sharing and analysis

Brain connectomics research has rapidly expanded using functional MRI (fMRI) and diffusion-weighted MRI (dwMRI). A common product of these varied analyses is a connectivity matrix (CM). A CM stores the connection strength between any two regions (“nodes”) in a brain network. This format is useful for several reasons: (1) it is highly distilled, with minimal data size and complexity, (2) graph theory can be applied to characterize the network's topology, and (3) it retains sufficient information to capture individual differences such as age, gender, intelligence quotient (IQ), or disease state. Here we introduce the UCLA Multimodal Connectivity Database (http://umcd.humanconnectomeproject.org), an openly available website for brain network analysis and data sharing. The site is a repository for researchers to publicly share CMs derived from their data. The site also allows users to select any CM shared by another user, compute graph theoretical metrics on the site, visualize a report of results, or download the raw CM. To date, users have contributed over 2000 individual CMs, spanning different imaging modalities (fMRI, dwMRI) and disorders (Alzheimer's, autism, Attention Deficit Hyperactive Disorder). To demonstrate the site's functionality, whole brain functional and structural connectivity matrices are derived from 60 subjects' (ages 26–45) resting state fMRI (rs-fMRI) and dwMRI data and uploaded to the site. The site is utilized to derive graph theory global and regional measures for the rs-fMRI and dwMRI networks. Global and nodal graph theoretical measures between functional and structural networks exhibit low correspondence. This example demonstrates how this tool can enhance the comparability of brain networks from different imaging modalities and studies. The existence of this connectivity-based repository should foster broader data sharing and enable larger-scale meta-analyses comparing networks across imaging modality, age group, and disease state.

Autism-associated promoter variant in MET impacts functional and structural brain networks

As genes that confer increased risk for autism spectrum disorder (ASD) are identified, a crucial next step is to determine how these risk factors impact brain structure and function and contribute to disorder heterogeneity. With three converging lines of evidence, we show that a common, functional ASD risk variant in the Met Receptor Tyrosine Kinase (MET) gene is a potent modulator of key social brain circuitry in children and adolescents with and without ASD. MET risk genotype predicted atypical fMRI activation and deactivation patterns to social stimuli (i.e., emotional faces), as well as reduced functional and structural connectivity in temporo-parietal regions known to have high MET expression, particularly within the default mode network. Notably, these effects were more pronounced in individuals with ASD. These findings highlight how genetic stratification may reduce heterogeneity and help elucidate the biological basis of complex neuropsychiatric disorders such as ASD.

Insights into multimodal imaging classification of ADHD

Attention deficit hyperactivity disorder (ADHD) currently is diagnosed in children by clinicians via subjective ADHD-specific behavioral instruments and by reports from the parents and teachers. Considering its high prevalence and large economic and societal costs, a quantitative tool that aids in diagnosis by characterizing underlying neurobiology would be extremely valuable. This provided motivation for the ADHD-200 machine learning (ML) competition, a multisite collaborative effort to investigate imaging classifiers for ADHD. Here we present our ML approach, which used structural and functional magnetic resonance imaging data, combined with demographic information, to predict diagnostic status of individuals with ADHD from typically developing (TD) children across eight different research sites. Structural features included quantitative metrics from 113 cortical and non-cortical regions. Functional features included Pearson correlation functional connectivity matrices, nodal and global graph theoretical measures, nodal power spectra, voxelwise global connectivity, and voxelwise regional homogeneity. We performed feature ranking for each site and modality using the multiple support vector machine recursive feature elimination (SVM-RFE) algorithm, and feature subset selection by optimizing the expected generalization performance of a radial basis function kernel SVM (RBF-SVM) trained across a range of the top features. Site-specific RBF-SVMs using these optimal feature sets from each imaging modality were used to predict the class labels of an independent hold-out test set. A voting approach was used to combine these multiple predictions and assign final class labels. With this methodology we were able to predict diagnosis of ADHD with 55% accuracy (versus a 39% chance level in this sample), 33% sensitivity, and 80% specificity. This approach also allowed us to evaluate predictive structural and functional features giving insight into abnormal brain circuitry in ADHD.

Modeling rare species distribution at the edge: the case for the vulnerable endemic Pyrenean desman in France

The endemic Pyrenean Desman (Galemys pyrenaicus) is an elusive, rare, and vulnerable species declining over its entire and narrow range (Spain, Portugal, France, and Andorra). The principal set of conservation measures in France is a 5-years National Action Plan based on 25 conservation actions. Priority is given to update its present distribution and develop tools for predictive distribution models. We aim at building the first species distribution model and map for the northern edge of the range of the Desman and confronting the outputs of the model to target conservation efforts in the context of environmental change. Contrasting to former comparable studies, we derive a simpler model emphasizing the importance of factors linked to precipitation and not to the temperature. If temperature is one of the climate change key factors, depicted shrinkage in Desman distribution could be lower or null at the northern (French) edge suggesting thus a major role for this northern population in terms of conservation of the species. Finally, we question the applied issue of temporal and spatial transferability for such environmental favourability models when it is made at the edge of the distribution range.

A Framework for 3D Model-Based Visual Tracking Using a GPU-Accelerated Particle Filter

A novel framework for acceleration of particle filtering approaches to 3D model-based, markerless visual tracking in monocular video is described. Specifically, we present a methodology for partitioning and mapping the computationally expensive weight-update stage of a particle filter to a graphics processing unit (GPU) to achieve particle- and pixel-level parallelism. Nvidia CUDA and Direct3D are employed to harness the massively parallel computational power of modern GPUs for simulation (3D model rendering) and evaluation (segmentation, feature extraction, and weight calculation) of hundreds of particles at high speeds. The proposed framework addresses the computational intensity that is intrinsic to all particle filter approaches, including those that have been modified to minimize the number of particles required for a particular task. Performance and tracking quality results for rigid object and articulated hand tracking experiments demonstrate markerless, model-based visual tracking on consumer-grade graphics hardware with pixel-level accuracy up to 95 percent at 60+ frames per second. The framework accelerates particle evaluation up to 49 times over a comparable CPU-only implementation, providing an increased particle count while maintaining real-time frame rates.

Growth hormone transgenesis does not influence territorial dominance or growth and survival of first-feeding Atlantic salmon Salmo salar in food-limited stream microcosms

This study explored the relative competitive ability and performance of first-feeding growth hormone (GH) transgenic and non-transgenic Atlantic salmon Salmo salar fry under low food conditions. Pair-wise dominance trials indicated a strong competitive advantage for residents of a contested foraging territory. Transgenic and non-transgenic individuals, however, were equally likely to be dominant. Similarly, in stream environments with limited food, the transgene did not influence the growth in mass or survival at high or low fry densities. Fry in low-density treatments, however, performed better than fry in high-density treatments. These results indicate that, under the environment examined, the growth performance of GH-transgenic and non-transgenic S. salar may be similar during first feeding, an intense period of selection in their life history. Similarities in competitive ability and growth performance with wild-type fish suggest that the capacity of transgenic S. salar to establish in natural streams may not be inhibited during early life history.

Altered structural brain connectivity in healthy carriers of the autism risk gene, CNTNAP2

Recently, carriers of a common variant in the autism risk gene, CNTNAP2, were found to have altered functional brain connectivity using functional MRI. Here, we scanned 328 young adults with high-field (4-Tesla) diffusion imaging, to test the hypothesis that carriers of this gene variant would have altered structural brain connectivity. All participants (209 women, 119 men, age: 23.4±2.17 SD years) were scanned with 105-gradient high-angular-resolution diffusion imaging (HARDI) at 4 Tesla. After performing a whole-brain fiber tractography using the full angular resolution of the diffusion scans, 70 cortical surface-based regions of interest were created from each individual's co-registered anatomical data to compute graph metrics for all pairs of cortical regions. In graph theory analyses, subjects homozygous for the risk allele (CC) had lower characteristic path length, greater small-worldness and global efficiency in whole-brain analyses, and lower [corrected] eccentricity (maximum path length) in 60 of the 70 nodes in regional analyses. These results were not reducible to differences in more commonly studied traits such as fiber density or fractional anisotropy. This is the first study that links graph theory metrics of brain structural connectivity to a common genetic variant linked with autism and will help us understand the neurobiology of the circuits implicated in the risk for autism.

A piezoelectric bone-conduction bending hearing actuator

A prototype of a novel bone-conduction hearing actuator based on a piezoelectric bending actuator is presented. The device lies flat against the skull which would allow it to form the basis of a subcutaneous bone-anchored hearing aid. The actuator excites bending in bone through a local bending moment rather than the application of a point force as with conventional bone-anchored hearing aids. Through measurements of the cochlear velocity created by the actuator in embalmed human heads, the device is shown to exhibit high efficiency, making it a possible alternative to present-day electromagnetic bone-vibration actuators.

Antidiuretic action of angiotensin II in the river lamprey Lampetra fluviatilis: evidence for endocrine control of kidney function in cyclostomes

Intravenous infusion of angiotensin II ([Asn¹ Val⁵]-Ang II) at 10⁻⁹ mol min⁻¹ kg⁻¹ body mass produced a significant antidiuresis in river lamprey Lampetra fluviatilis, captured during upstream migration and maintained in fresh water. Although the renin-angiotensin hormonal system (RAS) is now recognized in jawless fishes, until this study, the role of homologous Ang II in L. fluviatilis kidney function had not been examined. This study provides the first evidence for an antidiuretic action of Ang II in cyclostomes and, in evolutionary terms, suggests a renal function for the RAS in early vertebrates.

Conserved and variable architecture of human white matter connectivity

Whole-brain network analysis of diffusion imaging tractography data is an important new tool for quantification of differential connectivity patterns across individuals and between groups. Here we investigate both the conservation of network architectural properties across methodological variation and the reproducibility of individual architecture across multiple scanning sessions. Diffusion spectrum imaging (DSI) and diffusion tensor imaging (DTI) data were both acquired in triplicate from a cohort of healthy young adults. Deterministic tractography was performed on each dataset and inter-regional connectivity matrices were then derived by applying each of three widely used whole-brain parcellation schemes over a range of spatial resolutions. Across acquisitions and preprocessing streams, anatomical brain networks were found to be sparsely connected, hierarchical, and assortative. They also displayed signatures of topo-physical interdependence such as Rentian scaling. Basic connectivity properties and several graph metrics consistently displayed high reproducibility and low variability in both DSI and DTI networks. The relative increased sensitivity of DSI to complex fiber configurations was evident in increased tract counts and network density compared with DTI. In combination, this pattern of results shows that network analysis of human white matter connectivity provides sensitive and temporally stable topological and physical estimates of individual cortical structure across multiple spatial scales.

Hypoxia and cell cycle regulation of the von Hippel-Lindau tumor suppressor

Inactivation of von Hippel-Lindau tumor suppressor protein (pVHL) is associated with von Hippel-Lindau disease, an inherited cancer syndrome, as well as the majority of patients with sporadic clear cell renal carcinoma (RCC). While the involvement of pVHL in oxygen sensing through targeting HIFα subunits to ubiquitin-dependent proteolysis has been well documented, less is known about pVHL regulation under both normoxic and hypoxic conditions. We found that pVHL levels decreased in hypoxia and that hypoxia-induced cell cycle arrest is associated with pVHL expression in RCC cells. pVHL levels fluctuate during the cell cycle, paralleling cyclin B1 levels, with decreased levels in mitosis and G1. pVHL contains consensus Destruction box sequences, and pVHL associates with Cdh1, an activator of the anaphase promoting complex/cyclosome (APC/C) E3 ubiquitin ligase. We show that pVHL has a decreased half-life in G1, Cdh1 downregulation results in increased pVHL expression, while Cdh1 overexpression results in decreased pVHL expression. Taken together these results suggest that pVHL is a novel substrate of APC/C^Cdh1. Destruction box-independent pVHL degradation was also detected, indicating that other ubiquitin ligases are also activated for pVHL degradation.

Heat Shock Induction of Manganese Peroxidase Gene Transcription in Phanerochaete chrysosporium

The expression of manganese peroxidase (MnP) in nitrogen-limited cultures of Phanerochaete chrysosporium is regulated by heat shock at the level of gene transcription. Nitrogen limitation and manganous ion [Mn(II)] previously have been shown to regulate mnp gene transcription. Northern (RNA) blot analysis demonstrates that 45 degrees C heat shock results in the accumulation of mnp mRNA, even in cells grown in the absence of Mn. Heat shock induces mnp gene transcription in 4- or 5-day-old cells, and mnp mRNA is detectable after 15 min at 45 degrees C. Maximum accumulation of mnp mRNA is observed 1 to 2 h after transfer of cultures to 45 degrees C. Two hours after heat shock-induced cultures grown in the absence of Mn are transferred back to 37 degrees C, mnp mRNA is no longer detectable. Higher levels of mnp mRNA are obtained with simultaneous induction by Mn and heat shock than by either treatment alone. Neither MnP enzyme activity nor protein is detectable in heat-shocked cultures grown in the absence of Mn. However, higher MnP activity is found in the extracellular medium of cultures induced by both heat shock and Mn than in the medium of cultures induced by Mn alone. These results suggest that the putative heat shock elements found in the promoter region of the mnp genes are physiologically functional and that Mn may be required for a posttranscriptional step of MnP production under heat shock conditions.

Changes in arterial, mixed venous and intraerythrocytic concentrations of ions in supramaximally exercising horses

REASONS FOR PERFORMING STUDY

Horses experience major perturbations in acid-base balance during supramaximal exercise. Ion movement in and out of erythrocytes (RBCs) is believed to be important in maintaining acid-base balance but it is unclear as to the extent to which this happens, nor how it affects single measurements of ion concentrations in arterial and venous blood.

OBJECTIVES

To clarify the role RBCs play in mitigating perturbations in acid-base balance during high speed exercise in horses, and to describe associated differences in arterial (a) and mixed venous (v) concentrations of key ions.

METHODS

Six exercise-trained Thoroughbreds galloped to fatigue at speeds calculated to have an oxygen demand that was 115% of the VO2max. Blood samples (a and v) were collected pre-exercise, during warm-up, at fatigue, and immediately post exercise. Packed cell volume (PCV), pH, PCO2, and plasma concentrations of bicarbonate (HCOP3-), chloride (Cl-), sodium (Na+), potassium (K+), and lactate (Lac-) and strong ion difference (SID) were determined, and RBC concentrations of Lac- and electrolytes calculated for each sample. Data were analysed using a 2-way ANOVA for repeated measures testing for effects of sampling time and site (P<0.05).

RESULTS

Plasma and RBC [Cl-] were increased with hypercapnoea and acidaemia. [HCO3-]v was greater than pre-exercise values at fatigue, although [HCO3l]a was lower. Hyperkalaemia and decreased RBC [K+] were evident at fatigue, as was an increased RBC [Na+]. Plasma [K+] started to decrease as soon as exercise ceased and Na+ began to move back onto RBCs in exchange for K+. Concentrations of all measures of Lac- rose from fatigue to post exercise. The SID decreased with exercise and was higher in v at fatigue and post exercise, reflecting the decrease in pH.

CONCLUSIONS

RBCs act as a repository for lactate, and therefore the increase in PCV facilitates the maintenance of the muscle to plasma Lac- diffusion gradient during exercise.

POTENTIAL RELEVANCE

This serves to keep intramuscular [Lac-] lower than it would otherwise be and, because of the link between Lac- accumulation, pH decrease and the onset of fatigue, may help delay the onset of fatigue.

Mastocytoma in the common carpal sheath of the digital flexor tendons of a horse

A 13-year-old Morgan gelding was examined for right forelimb lameness and tenosynovitis of the right common carpal sheath of the digital flexor tendons. The horse had moderate right forelimb lameness at the trot and marked effusion of the right common carpal sheath of the digital flexor tendons. Ultrasonographic examination revealed a soft tissue mass within the proximal pouch of the affected tendon sheath, located adjacent to the distal physis of the radius. Cytology and culture of the fluid revealed a sterile, eosinophilic tenosynovitis. Tenoscopic exploration confirmed the presence of a capsulated soft tissue mass. Thecotomy was required to fully debride the mass, which histology revealed to be a mast cell tumour. At 22 months postoperatively, the horse developed mild right forelimb lameness and eosinophilic tenosynovitis because of recurrence of the mastocytoma. Mastocytosis is a possible differential diagnosis in any horse exhibiting lameness associated with tenosynovitis. Surgical excision combined with rest and postoperative intrasynovial and systemic corticosteroids may be palliative.

Effect of laryngoplasty on respiratory noise reduction in horses with laryngeal hemiplegia

REASONS FOR PERFORMING STUDY

Laryngoplasty is the technique of choice for treatment of laryngeal hemiplegia, with the aim of improving airway function and/or eliminating respiratory noise. However, there are no quantitative data in the literature describing the effect of laryngoplasty on upper airway noise or its relationship to upper airway mechanics in horses with laryngeal hemiplegia.

OBJECTIVES

To determine whether laryngoplasty reduces respiratory noise in exercising horses with laryngeal hemiplegia; and to establish whether the degree of upper airway obstruction can be predicted by upper airway noise, or the degree of arytenoid abduction correlated with airway obstruction and noise production.

METHODS

Six Standardbred horses with normal upper airways during maximal exercise were used. Respiratory sounds and inspiratory transupper airway pressure (Pui) were measured in all horses before and after induction of laryngeal hemiplegia and 30, 60 and 90 days after laryngoplasty. Inspiratory sound level (SL) and the sound intensity of the 3 inspiratory formants (F1, F2 and F3, respectively) were measured using a computer-based sound analysis programme. The degree of abduction was graded by endoscopic visualisation 1, 30, 60 and 90 days post operatively. Linear regression analysis was used to determine correlations between Pui, sound indices and grades of arytenoid abduction.

RESULTS

In laryngeal hemiplegia-affected horses, Pui, inspiratory SL and the sound intensity of F1, F2 and F3 were significantly increased. At 30 days following laryngoplasty, the sound intensity of F1 and Pui returned to baseline values. The sound intensities of F2, F3 and SL were significantly improved from laryngeal hemiplegia values at 30 days post operatively, but did not return to baseline at any measurement period. Sound level, F2 and F3 were significantly correlated with Pui (P<0.05), but the correlations were weak (r2 = 0.26, 035 and 0.40, respectively). Grade of abduction and F2 were positively and significantly correlated (P<0.006, r2 = 0.76). Grade of arytenoid abduction and Pui were not correlated (P = 0.12).

CONCLUSIONS

Laryngoplasty reduced inspiratory noise in laryngeal hemiplegia-affected horses by 30 days following surgery, but did not return it to baseline values. While upper airway noise and Pui were correlated, this relationship was insufficiently strong to predict Pui from noise in individual animals. The degree of arytenoid abduction was not correlated with Pui, but was positively correlated with noise production.

POTENTIAL RELEVANCE

Laryngoplasty reduces upper airway noise in horses with laryngeal hemiplegia, but is not as effective as bilateral ventriculocordectomy in this regard, although respiratory noise reduction occurs more rapidly than with bilateral ventriculocordectomy. Residual noise during exercise cannot be used as a predictor of improvement in upper airway function in individual horses following laryngoplasty. The degree of arytenoid abduction obtained following surgery does not affect upper airway flow mechanics. Interestingly, we found that the greater the arytenoid abduction, the louder the respiratory noise.

Prevalence of pharyngeal and laryngeal abnormalities in Thoroughbreds racing in Australia, and their association with performance

REASONS FOR PERFORMING STUDY

Little information is available regarding the prevalence of abnormalities of the upper airway and their association with performance in the general population of Thoroughbred racehorses.

OBJECTIVES

To describe the prevalence of selected abnormalities of the upper airway and their association with performance in Thoroughbred racehorses in Australia.

HYPOTHESIS

That abnormalities of the upper airway of Thoroughbred racehorses are associated with poor race performance.

METHODS

Rhinolaryngoscopy was performed after racing and presence and characteristics of abnormalities of the larynx and pharynx were recorded in a prospective cross-sectional study of Thoroughbred horses racing in Victoria, Australia.

RESULTS

Rhinolaryngoscopy was performed once on each of 744 horses over 35 months. Fifty abnormalities of the upper airway were detected in 47 horses (6.3%, 95% confidence interval [CI] 4.7-83%). Epiglottic entrapment was detected in 7 horses (0.9%, 95% CI 0.4-1.9%) and was significantly (P = 0.015) associated with superior performance. Grade 2 asymmetry (4 grade scale) of the left arytenoid cartilage was detected in 9 horses (1.2%, 95% CI 0.5-2.4%) and was also associated with superior performance (P<0.001). Ulceration or erosion of the mucosa of the axial surface of one or both arytenoids was detected in 18 horses (2.4%, 95% CI 13-3.8%) and was not associated with alterations in exercise performance (P = 0.31).

CONCLUSIONS

Epiglottic entrapment, Grade 2 laryngeal asymmetry and mucosal erosions detected in Thoroughbred racehorses were not associated with impaired performance; therefore, surgical correction and concern over laryngeal function in horses with Grade 2 asymmetry may not be necessary in individuals performing to expectation.

Ventriculocordectomy reduces respiratory noise in horses with laryngeal hemiplegia

REASONS FOR PERFORMING STUDY

Show and performance horse with laryngeal hemiplegia (LH) often present for excessive respiratory noise rather than significant exercise intolerance. Therefore, the goal of surgery in these horses is to reduce respiratory noise but there are no quantitative studies evaluating the effect of any upper-airway surgery in LH-affected horses.

OBJECTIVE

To determine whether bilateral ventriculocordectomy (VC) reduces respiratory noise in exercising horses with laryngeal hemiplegia.

METHODS

Six Standardbred horses with normal upper airways were used in this study. Respiratory sounds and inspiratory trans-upper airway pressure (Pui) were measured in all horses before and after induction of LH, and 30, 90 and 120 days after VC. In horses with LH, spectrogram analysis revealed 3 inspiratory sound formants centred at approximately 400, 1700 and 3700 Hz. Inspiratory sound levels (SL) and the sound intensity of the 3 inspiratory formants (F1, F2, F3 respectively) were measured using a computer-based sound analysis programme.

RESULTS

In LH-affected horses, Pui, inspiratory SL and the sound intensity of F2 and F3 were significantly increased compared to baseline values. At 90 and 120 days after VC the sound intensities of F2 and F3 returned to baseline values. The Pui and SL, were significantly decreased compared to LH values, but remained different from baseline.

CONCLUSIONS

VC effectively reduces inspiratory noise in LH-affected horses by 90 days following surgery. Inspiratory trans-upper airway pressures are improved 30 days following VC, but do not return to baseline values.

POTENTIAL RELEVANCE

VC can be recommended as a surgical treatment of LH-affected horses if reduction of respiratory noise is the primary objective of surgery. Further studies are required to determine if variations of the surgical technique used in this study will have similar results.

Heart rate variability and ventilatory efficiency

The aims of this investigation were to identify possible associations between the resting high frequency component of heart rate variability and measures of ventilatory efficiency, determined during exercise, in a group of endurance trained athletes. V'E, V'CO2, and V'O2 were measured during incremental exercise up to the anaerobic threshold (AT) and up to volitional exhaustion (V'O2 max) in 12 subjects. Resting high frequency heart rate variability (HF(NU)), determined using spectral analysis of ECG traces, was correlated with the V'E vs. V'CO2 slope calculated from data up to the AT, where a negative linear relation between the V'E vs. V'CO2 slope and HF (NU) was recorded (R(2)=0.69). Also, resting HF (NU) was correlated with the V'E vs. V'CO (2) slope, when the data used for slope calculation included all V'E vs. V'CO2 data up to V'O2 max (R(2)=0.56). However, there was no evidence of association between the minimum V'E:V'CO (2) and resting HF(NU) (R(2)=0.08). Negative relations between V'E vs. V'CO2 slope and resting HF(NU) suggest that HF(NU) plays a role in matching blood flow in the lung to alveolar ventilation throughout the ventilatory cycle.

Indirect measures of human vagal withdrawal during head-up tilt with and without a respiratory acidosis

Human ECG records were analyzed during supine (SUP) rest and whole body 80 degrees head-up tilt (HUT), with a respiratory acidosis (5%CO(2)) and breathing room air (RA). HUT increased heart rate in both conditions (RA(SUP) 60 +/- 13 vs. RA(HUT) 79 +/- 16; 5%CO(2SUP) 63 +/- 12 vs. 5%CO(2HUT) 79 +/- 14 beats min(-1)) and decreased mean R-R interval, with no changes in the R-R interval standard deviation. When corrected for changes in frequency spectrum total power (NU), the high frequency (0.15-0.4 Hz) component (HF(NU)) of heart rate variability decreased (RA(SUP) 44.01 +/- 21.57 vs. RA(HUT) 24.05 +/- 13.09; 5%CO(2SUP) 69.23 +/- 15.37 vs. 5%CO(2HUT) 47.64 +/- 21.11) without accompanying changes in the low frequency (0.04-0.15 Hz) component (LF(NU)) (RA(SUP) 52.36 +/- 21.93 vs. RA(HUT) 66.58 +/- 19.49; 5%CO(2SUP) 22.97 +/- 11.54 vs. 5%CO(2HUT) 40.45 +/- 21.41). Positive linear relations between the tilt-induced changes (Delta) in HF(NU) and R-R interval were recorded for RA (DeltaHF(NU) = 0.0787(DeltaR-R) - 11.3, R (2) = 0.79, P < 0.05), and for 5%CO(2) (DeltaHF(NU) = 0.0334(DeltaR-R) + 1.1, R (2) = 0.82, P < 0.05). The decreased HF component suggested withdrawal of vagal activity during HUT. For both RA and 5%CO(2), the positive linear relations between DeltaHF(NU) and DeltaR-R suggested that the greater the increase in heart rate with HUT, the greater the vagal withdrawal. However, a reduced range of DeltaHF during HUT with respiratory acidosis suggested vagal withdrawal was lower with a respiratory acidosis.

An internet database for the classification and dissemination of information about hazardous chemicals and occupational diseases

BACKGROUND

The amount of information about hazardous agents in the workplace exceeds the capacity of human memory. There is a need to accurately represent or map this scientific knowledge for digital storage and retrieval.

METHODS

A relational database of hazardous chemicals and occupational diseases was constructed by first collecting and sifting through the large volume of information. The information was indexed with a controlled vocabulary and documented with references to the scientific literature.

RESULTS

The evolving database is available on the website of the National Library of Medicine. It enables users to browse categories and query by pick lists. Users can drill down to find specific information that may be useful for intervention and prevention.

CONCLUSIONS

The large amount of information needed to support decisions concerning occupational exposures and diseases can be distilled, classified, and summarized in a relational database and disseminated by means of the World Wide Web to assist in the prevention of work-related diseases.

Cardiac vagal control and respiratory sinus arrhythmia during hypercapnia in humans

Normoxic hypercapnia may increase high-frequency (HF) power in heart rate variability (HRV) and also increase respiratory sinus arrhythmia (RSA). Low-frequency (LF) power may remain unchanged. In this study, 5-min ECG recordings (N = 10) were analyzed in time and frequency domains while human subjects breathed normoxic 5% CO2 (5%CO2) or room air (RA). Tidal volume (VT), inhalatory (TI), and exhalatory (TE) times of breaths in the final minute were measured. ECG time domain measures were unaffected by CO2 inhalation (P > 0.05). Following natural logarithmic transformation (LN), LFLN was unaltered (RA: 7.14 +/- 0.95 vs. 5%CO2: 7.35 +/- 1.12, P > 0.05), and HFLN increased (RA: 7.65 +/- 1.37 vs. 5%CO2: 8.58 +/- 1.11, P < 0.05) with CO2 inhalation. When changes in total power (NU) were corrected, LF(NU) decreased (RA: 34.4 +/- 22.9 vs. 5%CO2: 23.8 +/- 23.1, P < 0.01), and HFNU increased (RA: 56.5 +/- 22.3 vs. 5%CO2: 66.8 +/- 22.9, P < 0.01) with CO2 inhalation. TI (RA: 2.0 +/- 1.0 vs. 5%CO2: 1.9 +/- 0.8 s) and TE (RA: 2.5 +/- 1.1 vs. 5%CO2: 2.4 +/- 0.9 s) remained unchanged, but VT increased with CO2 inhalation (RA: 1.1 +/- 0.3 vs. 5%CO2: 2.0 +/- 0.8 L, P < 0.001). Heart rates during inhalation (RA: 35.2 +/- 4.4, 5%CO2: 34.5 +/- 4.8 beats min(-1)) were different from heart rates during exhalation (RA: 28.8 +/- 4.4, 5%CO2: 29.1 +/- 3.1 beats min(-1)). Hypercapnia did not increase the clustering of heart beats during inhalation, and we suggest that the HF component may not adequately reflect RSA.

Uterus unicornis in two mares

Two American Paint Horses, a 3-year-old nulliparous mare and a 7-year-old primiparous mare, presented for recent infertility and a pre-breeding examination, respectively. Examination of the internal reproductive tract of both mares using transrectal palpation and ultrasonography revealed the presence of the cervix, uterine body, left uterine horn and bilateral ovaries. The right uterine horn could neither be palpated nor imaged. The clinical diagnosis of uterus unicornis in one mare was confirmed at necropsy, which revealed combined aplasia of the right uterine horn and oviduct.

Pigs weaned from the sow at 10 days of age respond to dietary energy source of manufactured liquid diets and exogenous porcine somatotropin

Previous research indicates that the neonatal pig does not alter feed intake in response to changes in the energy density of manufactured liquid diets. Also, the limited response of IGF-I to exogenous porcine ST (pST) previously observed in young pigs may be influenced by the source of dietary energy. Our objectives were to 1) determine the effect of a high-fat (HF; 25% fat and 4,639 kcal/kg ME; DM basis) or low-fat (LF; 2% fat and 3,481 kcal/kg ME; DM basis) manufactured liquid diet on pig performance; and 2) determine whether the limited response to exogenous pST in young pigs depends on the source of dietary energy. Two replicates of 60 pigs (n = 120; barrows and gilts distributed evenly), with an initial BW of 4,207 +/- 51 g, were weaned from the sow at 10 d of age and used in a randomized complete block design. Pigs were assigned by BW to one of six pens. Diets were formulated to provide a constant lysine:ME ratio and were fed on a pen basis for a duration of 9 d. On d 5, barrows and gilts within a pen were assigned randomly to receive either 0 or 120 microg of pST.kg BW(-1).d(-1) for 4 d. Pigs gained 336 +/- 9 g/d, which resulted in an ending BW of 7,228 +/- 120 g, regardless of dietary treatment (P > 0.15). Pigs fed the LF diet consumed 17% more DM per pen daily than pigs fed the HF diet (2,777 +/- 67 vs. 2,376 +/- 67 g/d, P < 0.01), but calculated ME intake did not differ between dietary treatments (P > 0.20). The G:F was 24% greater in HF- than in LF-fed pigs (P < 0.01). Plasma urea N concentrations were higher in the HF-fed pigs (11.0 +/- 0.6 mg/dL) than in pigs fed the LF diet (6.2 +/- 0.6 mg/dL; P < 0.05). Treatment with pST increased circulating IGF-I (P < 0.01) and decreased PUN (P < 0.01) concentration 32 and 25%, respectively, regardless of dietary treatment (P > 0.30). Circulating leptin averaged 1.8 +/- 0.1 ng/mL and was not affected by dietary treatment (P > 0.35) or pST (P > 0.40). These results suggest that the ST/IGF axis is responsive in the young pig and the increase in circulating IGF-I and growth is independent of the source of dietary energy. Also, young pigs respond to a lower energy density liquid diet with increased feed intake, without altering growth performance, apparently utilizing a mechanism other than circulating leptin.

Ultrasound versus 'clinical touch' for catheter guidance during embryo transfer in women

BACKGROUND

Many women undergoing an Assisted Reproductive Technology (ART) cycle will not achieve a live birth. Failure at the embryo transfer stage may be due to poor embryo quality, lack of uterine receptivity, or the transfer technique itself. Numerous methods, including the use of ultrasound guidance for proper catheter placement in the endometrial cavity, have been suggested as a means of improving the technique of embryo transfer. This review evaluates the effectiveness of ultrasound (UGET) in comparison with 'clinical touch' embryo transfer (CTET) the traditional method of embryo transfer.

OBJECTIVES

:To determine whether ultrasound guidance influences treatment outcomes in women undergoing embryo transfer (ET) during assisted reproductive technology (ART) cycles.

SEARCH STRATEGY

All electronic databases were searched on 20 th August 2006. We searched the Cochrane Menstrual Disorders and Subfertility Group trials register (searched August 2006), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2006), MEDLINE (1970-2006), EMBASE (1985-2006), BIO Extracts (1980-2006). Relevant conference proceedings were also hand searched (ASRM, ESHRE and FIGO).

SELECTION CRITERIA

Only randomised controlled trials were included.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed eligibility and quality of trials and extracted data from those selected.

MAIN RESULTS

Thirteen out of fifteen identified studies were eligible for analysis. No study reported live births, however, personal communication resulted in data relating to this outcome being obtained in two of the studies. Six studies reported on ongoing pregnancies. The live birth/ ongoing pregnancies per woman randomised associated with UGET (452/1376) was significantly higher than for clinical touch (353/1338) OR 1.40, 95%CI 1.18 to 1.66, P<0.0001). This means, for example, that for a population of women with a 25% chance of pregnancy using clinical touch this would be increased to 32% (28% to 46%) by using UGET. There were no statistically significant differences in the incidence of adverse events between the two comparison groups with the exception of blood on the catheter.

AUTHORS' CONCLUSIONS

The studies are limited by their quality with only one of the thirteen studies reporting details of both computerised randomisation techniques and adequate allocation concealment. Ultrasound guidance does appear to improve the chances of live/ongoing and clinical pregnancies compared with clinical touch methods. The quality of future studies should be improved with adequate reporting of randomisation, allocation concealment, and power calculations. The primary outcome measure of future studies should be the reporting of live births per woman randomised.

Major histocompatibility complex and kin discrimination in Atlantic salmon and brook trout

Many species of salmonids can discriminate kin from unrelated conspecifics using olfactory cues. In this study, we determined the role of the major histocompatibility complex (MHC) in kin discrimination by juvenile Atlantic salmon (Salmo salar) and brook trout (Salvelinus fontinalis). Genetic variation at the highly polymorphic exon coding for peptide-binding region of an MHC class II gene was studied using polymerase chain reaction and denaturing gradient gel electrophoresis. Experiments compared discrimination ability based on MHC haplotypes both within and among kin and non-kin groups. Juveniles chose kin sharing both alleles over kin sharing no alleles. Juveniles also preferred non-kin sharing both alleles to non-kin sharing no alleles. These data suggest that the MHC class II gene influence kin discrimination in juvenile Atlantic salmon and brook trout. The influence of additional genes was also apparent in trials where juveniles were able to recognize kin sharing no alleles over non-kin sharing no alleles. However, the inability of juveniles to discriminate between kin sharing no alleles and non-kin sharing either one or both alleles indicates that MHC is as potent as the rest of the genome in producing distinguishable odours.

Resting and Postexercise Cardiac Autonomic Control in Trained Masters Athletes

This study used measures of heart rate variability during recovery from high-intensity exercise in trained Master athletes to examine postexercise cardiac autonomic regulation. Seven males (mean age 52.1 +/- 3.3 yr; mass 85.1 +/- 18.0 kg) and 6 females (mean age 50.5 +/- 2.9 yr; mass 63.1 +/- 6.0 kg) performed incremental exercise to an intensity that induced a >4.5 mmol capillary blood lactate concentration, followed by incremental exercise to volitional exhaustion (VO2(max)). A 6 min ECG recording before (Pre) and after (Post) exercise was analyzed in the time (mean rr interval, sd rr) and frequency domains (total power, very low frequency [VLF: 0-0.04 Hz], low frequency [LF: 0.04-0.15 Hz], high frequency [HF: 0.15-0.4 Hz]). VO2(max) for males and females was 49.4 +/- 7.1 ml kg(-1) min(-1) and 45.1 +/- 10.1 ml kg(-1) min(-1), respectively. Lower mean rr interval (Pre: 1,048 +/- 128 ms; Post: 730 +/- 78 ms; P < 0.001) and lower sd rr (Pre: 77 +/- 30 ms; Post: 43 +/- 17 ms; P < 0.001) were recorded following exercise, with no differences based on gender. Total power decreased following exercise (Pre: 6,331 +/- 6,119 ms; Post: 1,921 +/- 1,552 ms). When normalized for changes in total power, a decreased HF component (Pre: 34.52 +/- 14.79 n.u.; Post: 18.49 +/- 13.64 n.u.; P < 0.05) with no change in LF component (Pre: 61.00 +/- 18.66 n.u.; Post: 69.63 +/- 23.97 n.u.; P = 0.34) was recorded. No gender differences in HRV in the frequency domain were recorded. Decreased heart rate variability in both time and frequency domains suggested an increased parasympathetic withdrawal during the autonomic control of postexercise tachycardia in trained Master athletes.

Head module control of mediator interactions

Yeast Mediator proteins interacting with Med17(Srb4) have been expressed at a high level with the use of recombinant baculoviruses and recovered in homogeneous form as a seven subunit, 223 kDa complex. Electron microscopy and single-particle analysis identify this complex as the Mediator head module. The recombinant head module complements "headless" Mediator for the initiation of transcription in vitro. The module interacts with an RNA polymerase II-TFIIF complex, but not with the polymerase or TFIIF alone. This interaction is lost in the presence of a DNA template and associated RNA transcript, recapitulating the release of Mediator that occurs upon the initiation of transcription. Disruption of the head module in a temperature-sensitive mutant in vivo leads to the release of middle and tail modules from a transcriptionally active promoter. The head module evidently controls Mediator-RNA polymerase II and Mediator-promoter interactions.

Healthcare use before and after a workplace injury in British Columbia, Canada

OBJECTIVES

There is growing evidence that occupational injuries influence workers' emotional and physical wellbeing, extending healthcare use beyond what is covered by the Workers' Compensation Board (WCB).

METHODS

The authors used an administrative database that links individual publicly funded healthcare and WCB data for the population of British Columbia (BC), Canada. They examined change in service use, relative to one year before the injury, for workers who required time off for their injuries (lost time = LT) and compared them to other injured workers (no lost time = NLT) and individuals in the population who were not injured (non-injured = NI).

RESULTS

LT workers increased physician visits (22%), hospital days (50%), and mental healthcare use (43% physician visits; and 70% hospital days) five years after the injury, relative to the year before the injury, at a higher rate than the NI group. For the NLT workers, the level of increased use following the injury was between that of these two groups. These patterns persisted when adjusting for registration in the BC Medical Service Plan (MSP) and several workplace characteristics.

CONCLUSIONS

Although the WCB system is the primary mechanism for processing claims and providing information about workplace injury, it is clear that the consequences of workplace injury extend beyond what is covered by the WCB into the publicly funded healthcare system.

European eels, Anguilla anguilla (L.), infected with Anguillicola crassus exhibit a more pronounced stress response to severe hypoxia than uninfected eels

The parasite, Anguillicola crassus is a non-native species that infects naive European eels, Anguilla anguilla, and causes pathological damage to the swimbladder, potentially compromising their ability to cope with hypoxic conditions. This study aimed to elucidate whether anguillicolosis exacerbates the stress responses to exposure to hypoxic water, conditions that have been implicated in mass mortalities of wild infected European eels. Blood parameters in infected and uninfected eels were measured during exposure to severe hypoxia over an 8-h period. Infected fish showed significantly higher levels of plasma cortisol compared with uninfected eels after 4 h of hypoxia. Uninfected fish showed an almost twofold increase in plasma glucose after 8-h exposure to hypoxia but infected fish showed no significant change, so that the plasma glucose concentration was significantly higher in uninfected eels than in infected eels. Both groups showed similar elevations in blood haematocrit, suggesting a similar catecholamine response in infected and uninfected eels. The lack of a hyperglycaemic response in infected eels, despite indirect evidence of a catecholamine response to hypoxia, may reflect an increase in glucose turnover. The data suggest that anguillicolosis results in a significantly greater corticosteroid stress response to hypoxia accompanied by a higher metabolic cost.

Detection of influenza A in clinical specimens and cell culture fluid by a commercial EIA

A MoAb-based capture EIA for the direct detection of influenza A from clinical samples was compared with cell culture isolation. A total of 330 respiratory specimens were submitted for detection of influenza A and/or other respiratory viruses. Influenza A was detected in 39 of 330 (12%) respiratory samples by culture or EIA. There were 33 concordant (EIA+/Culture-) samples (82%), and 6 discordant samples (3 EIA +/Culture-; 3 EIA-/Culture+). Compared to viral isolation, the EIA had a sensitivity of 92%, a specificity of 98%, with positive and negative predictive values of 92% and 99%, respectively.

The role of hyaluronic acid in wound healing’s proliferative phase

This review discusses the multifaceted role of hyaluronic acid, focusing on the proliferative phase of wound healing. It considers the importance of achieving the right levels of this molecule, and the potential for future therapies.

Relationships Among Rheological and Sensorial Properties of Young Cheeses

This study investigated the sensory and rheological properties of young cheeses in order to better understand perceived cheese texture. Mozzarella and Monterey Jacks were tested at 4, 10, 17, and 38 d of age; process cheese was tested at 4 d. Rheological methods were used to determine the linear and nonlinear viscoelastic and fracture properties. A trained sensory panel developed a descriptive language and reference scales to evaluate cheese texture. All methods differentiated the cheeses by variety. Principal component analysis of sensory texture revealed that three principal components explained 96.1% of the total variation in the cheeses. The perception of firmness decreased as the cheeses aged, whereas the perception of springiness increased. Principal component analysis of the rheological parameters (three principal components: 87.9% of the variance) showed that the cheeses' solid-like response (storage modulus and fracture modulus) decreased during aging, while phase angle, maximum compliance, and retardation time increased. Analysis of the instrumental and sensory parameters (three principal components: 82.1% of the variance) revealed groupings of parameters according to cheese rigidity, resiliency, and chewdown texture. Rheological properties were highly associated with rigidity and resiliency, but less so with chewdown texture.

Esophageal foreign body causing direct aortic injury

Foreign bodies in the esophagus are uncommon causes of esophageal perforation. Many nonperforating cases are successfully managed by flexible gastroscopy. However, complicated foreign bodies such as those that result in esophageal perforation and vascular injury are best managed surgically. Gastroscopy remains the primary method of diagnosis. A case of a 59-year-old woman who developed retrosternal and intrascapular pain, odynophagia and hematemesis after eating fish is reported. Flexible gastroscopy showed arterial bleeding from the midthoracic esophagus. Computed tomography scan localized a 3 cm fish bone perforating the esophagus with surrounding hematoma. An aortogram did not reveal an actively bleeding aortoesophageal fistula. The fish bone was surgically removed and the patient recovered with no postoperative complications. This case illustrates the importance of early consideration for surgical intervention when confronted with a brisk arterial bleed from the esophagus with suggestive history of foreign body ingestion.

Nonsteroidal anti-inflammatory drug-induced colonic stricture: case report

Nonsteroidal anti-inflammatory drug-induced colonic strictures are uncommon and usually occur in the proximal ascending colon. We describe the progressive findings of nonsteroidal anti-inflammatory drug-induced strictures in the ascending colon and at the ileocecal valve with subsequent bowel obstruction secondary to intussusception.