Evaluation of peritoneal l-lactate concentration in horses in the early post-partum period

BACKGROUND

Peritoneal fluid lactate concentration is an important diagnostic tool in horses with abdominal pain. Information on peritoneal lactate concentrations is lacking following parturition in the mare.

OBJECTIVES

To compare blood and peritoneal lactate concentrations in a population of mares within 36 h post-partum, report a normal reference range and identify any impact of retained foetal membranes (RFMs).

METHODS

This is a retrospective study evaluating healthy mares from which blood and peritoneal samples had been obtained within 36 h of parturition. Exclusion criteria included signs of abdominal pain within this period. Data was interrogated for normality using a Shapiro-Wilk test. Wilcoxon signed-rank test and Bland-Altman analysis were used to compare blood and peritoneal lactate concentrations. Linear regression was used to compare age and breed data with peritoneal lactate concentrations. Significance was defined as p < 0.05.

RESULTS

Forty mares met the inclusion criteria. Mean age was 12.6 ± 4.1 years, and most mares were multiparous (65%). Peritoneal lactate ((1.2 (IQR = 0.9-1.6) mmol/L) was increased compared to blood lactate concentration (0.7 (IQR = 0-1.1)mmol/L; p < 0.001). Plasma total protein (TP) concentrations were 68 (IQR = 64-74) g/L and peritoneal protein concentrations 8 (IQR = 4-9.7) g/L. Six mares developed RFM. The median fold-increase in peritoneal lactate concentration compared to blood lactate concentration was 0.9 (IQR: 0.01-1.7; range: 0-2.5). The reference range for peritoneal fluid lactate concentration was 0-2.5 mmol/L.

CONCLUSION

Peritoneal lactate concentrations in healthy post-partum mares remained within the normal reference range and were not influenced by RFM or parturition. Increased peritoneal lactate in this group warrants further investigation.

Enhancing routine HIV and STI testing among young men who have sex with men: primary outcomes of the get connected clinical randomized trial (ATN 139)

BACKGROUND

Regular HIV and STI testing remain a cornerstone of comprehensive sexual health care. In this study, we examine the efficacy of Get Connected, a WebApp that combines test locators with personalized educational resources, in motivating young men who have sex with men (YMSM) to undergo regular HIV and STI testing.

METHODS

Participants were randomly placed in one of two conditions. The first condition included the full version of GC (GC-PLUS), which included content tailored to users' psychosocial characteristics (e.g., age, race/ethnicity, relationship status, HIV/STI testing history). The second condition served as our attention-control and only included the testing locator (GC-TLO) for HIV/STI testing services. Participants were recruited from three cities (Houston, Philadelphia, and Atlanta) characterized by high HIV incidence. Assessments were collected at 1, 3-, 6-, 9- and 12-month follow-ups.

RESULTS

Both versions of GC were acceptable and efficacious in increasing routine HIV and STI testing over a 12-month period. 40% of the sample reported testing at least twice, with no main effects observed across the two intervention arms (OR = 1.11; 95% CI: 0.69, 1.80), p =.66). Greater intervention effects were observed among YMSM who engaged more frequently with the intervention, with regional differences observed.

CONCLUSIONS

Our findings underscore the need to cater to the diverse needs of YMSM through multilevel approaches. Broadly, mHealth HIV/STI testing interventions, such as Get Connected, would benefit from matching technologies to the local context to have the greatest impact.

TRIAL REGISTRATION

This study is registered on ClinicalTrials.gov (NCT03132415).

Real-world application of tumor mutational burden-high (TMB-high) and microsatellite instability (MSI) confirms their utility as immunotherapy biomarkers

Introduction

Microsatellite instability (MSI) testing and tumor mutational burden (TMB) are genomic biomarkers used to identify patients who are likely to benefit from immune checkpoint inhibitors. Pembrolizumab was recently approved by the Food and Drug Administration for use in TMB-high (TMB-H) tumors, regardless of histology, based on KEYNOTE-158. The primary objective of this retrospective study was real-world applicability and use of immunotherapy in TMB/MSI-high patients to lend credence to and refine this biomarker.

Methods

Charts of patients with advanced solid tumors who had MSI/TMB status determined by next generation sequencing (NGS) (FoundationOne CDx) were reviewed. Demographics, diagnosis, treatment history, and overall response rate (ORR) were abstracted. Progression-free survival (PFS) was determined from Kaplan–Meier curves. PFS1 (chemotherapy PFS) and PFS2 (immunotherapy PFS) were determined for patients who received immunotherapy after progressing on chemotherapy. The median PFS2/PFS1 ratio was recorded.

Results

MSI-high or TMB-H [≥20 mutations per megabase (mut/MB)] was detected in 157 adults with a total of 27 distinct tumor histologies. Median turnaround time for NGS was 73 days. ORR for most recent chemotherapy was 34.4%. ORR for immunotherapy was 55.9%. Median PFS for patients who received chemotherapy versus immunotherapy was 6.75 months (95% confidence interval, 3.9-10.9 months) and 24.2 months (95% confidence interval, 9.6 months to not reached), respectively (P = 0.042). Median PFS2/PFS1 ratio was 4.7 in favor of immunotherapy.

Conclusion

This real-world study reinforces the use of TMB as a predictive biomarker. Barriers exist to the timely implementation of NGS-based biomarkers and more data are needed to raise awareness about the clinical utility of TMB. Clinicians should consider treating TMB-H patients with immunotherapy regardless of their histology.

•

This retrospective study examined the real-world use of immune checkpoint inhibitors (ICIs) in TMB/MSI-high patients with a diverse set of cancer types.

•

TMB is an emerging tumor-agnostic biomarker for response to treatment with ICIs that may expand personalized cancer care.

•

ICIs remain underutilized as a first-line therapy for TMB/MSI-H patients without specific histologic approval for ICIs.

•

The PFS2 to PFS1 ratio was 4.7, favoring immunotherapy over chemotherapy even as a second-line therapy.

•

Our study reinforces the real-world evidence that TMB is a valid surrogate marker for MSI and can predict response to ICIs.

Hugh Emlyn Davies

An impeccably presented country gentleman, he was a skilled equine veterinary surgeon who combined excellent client service with a no-nonsense approach and kept up to date with the latest developments.

Concordance in the reporting of intimate partner violence among male-male couples

Intimate partner violence (IPV) among male couples is increasingly recognized as a public health concern. Research on IPV in opposite sex couples indicates frequent underreporting of IPV and high levels of discordance in reporting among dyads. Concordance studies inform refinement methods to measure the experience of IPV among dyads; however the lack of dyadic studies of male couples impedes our understanding of the extent to which IPV is differentially reported in male-male dyads. This study utilized baseline data from a randomized controlled trial of a behavioral intervention to optimize antiretroviral therapy (ART) adherence among 160 sero-discordant male couples in three US cities and provides the first analysis of concordance in reporting IPV among male couples. Low degrees of concordance in the reporting of IPV were identified among male dyads, with a greater proportion of men reporting violence perpetration than experiencing violence. The greater reporting of IPV perpetration may be linked to adherence to concepts of masculinity. The results underscore the unique experiences of IPV among male couples and the need to reexamine current IPV measurement and intervention strategies.

Renal injury in a patient with lumbar scoliosis

Kidney laceration following blunt trauma is responsible for up to 3% of trauma cases. The risk factors associated with renal injury are attributed to the risks of mechanical injury. However, anatomical variations that may accelerate the insult of injury are poorly documented. This case report describes a 25-year-old with degenerative lumbar scoliosis who presented with flank pain and visible haematuria following a low-impact injury. The patient had a grade IV renal injury. The curvature of the spine, shown on CT imaging, revealed a reduced retroperitoneal space around the left kidney. This case explores lumbar scoliosis as a risk factor for kidney laceration. We hypothesise that this increased risk is associated with asymmetry of the spine and reduced anatomical space in the retroperitoneum. Patients with lumbar scoliosis may be considered a high-risk category for renal injury, following low-impact trauma.

Are Occupational Therapists Losing Sight of Hemianopia?

The purpose of this study was to determine the knowledge base surrounding hemianopia and to collate the rehabilitation principles offered by members of the National Association of Neurological Occupational Therapists (NANOT). A questionnaire was sent to 250 randomly selected members of NANOT. The completed questionnaires (n = 120) represented approximately a quarter of the total number of NANOT members at the time of the study.

The mean post-registration time of the respondents was 11 years (SD 0.6). All United Kingdom geographical areas apart from Northern Ireland and the Isle of Man were represented. A wide range of clinical areas was also represented.

The results showed that 92% of the respondents provided an accurate definition of hemianopia as the loss of half of the visual field. However, 48.3% reported that they were not testing every individual with a stroke for hemianopia. A third of the respondents stated that 80–100% of individuals with hemianopia always needed occupational therapy to compensate. The respondents also rated their understanding of eight neurovisual terms and, out of a total possible score of 80 (full understanding of terms), the mean score was 41 (SD 2.9).

The occupational therapist's role in the assessment/rehabilitation of hemianopia emerged in four categories: education, compensation, assessment of effects and diagnosis. Even if individuals were made aware of their hemianopia, 62% of the respondents reported that there were resulting problems in the individual's engagement in occupation (aspects of self-care, productivity and leisure).

These results are discussed in the context of the available literature and conclusions are drawn. A recommendation is made to improve the awareness and rehabilitation of individuals with hemianopia by occupational therapists.

Significance of the zero sum principle for circadian, homeostatic and allostatic regulation of sleep-wake state in the rat

Sleep-wake behavior exhibits diurnal rhythmicity, rebound responses to acute total sleep deprivation (TSD), and attenuated rebounds following chronic sleep restriction (CSR). We investigated how these long-term patterns of behavior emerge from stochastic short-term dynamics of state transition. Male Sprague-Dawley rats were subjected to TSD (1day×24h, N=9), or CSR (10days×18h TSD, N=7) using a rodent walking-wheel apparatus. One baseline day and one recovery day following TSD and CSR were analyzed. The implications of the zero sum principle were evaluated using a Markov model of sleep-wake state transition. Wake bout duration (a combined function of the probability of wake maintenance and proportional representations of brief and long wake) was a key variable mediating the baseline diurnal rhythms and post-TSD responses of all three states, and the attenuation of the post-CSR rebounds. Post-NREM state transition trajectory was an important factor in REM rebounds. The zero sum constraint ensures that a change in any transition probability always affects bout frequency and cumulative time of at least two, and usually all three, of wakefulness, NREM and REM. Neural mechanisms controlling wake maintenance may play a pivotal role in regulation and dysregulation of all three states.

Sleep deprivation does not affect neuronal susceptibility to mild traumatic brain injury in the rat

Mild and moderate traumatic brain injuries (TBIs) (and concussion) occur frequently as a result of falls, automobile accidents, and sporting activities, and are a major cause of acute and chronic disability. Fatigue and excessive sleepiness are associated with increased risk of accidents, but it is unknown whether prior sleep debt also affects the pathophysiological outcome of concussive injury. Using the "dark neuron" (DN) as a marker of reversible neuronal damage, we tested the hypothesis that acute (48 hours) total sleep deprivation (TSD) and chronic sleep restriction (CSR; 10 days, 6-hour sleep/day) affect DN formation following mild TBI in the rat. TSD and CSR were administered using a walking wheel apparatus. Mild TBI was administered under anesthesia using a weight-drop impact model, and the acute neuronal response was observed without recovery. DNs were detected using standard bright-field microscopy with toluidine blue stain following appropriate tissue fixation. DN density was low under home cage and sleep deprivation control conditions (respective median DN densities, 0.14% and 0.22% of neurons), and this was unaffected by TSD alone (0.1%). Mild TBI caused significantly higher DN densities (0.76%), and this was unchanged by preexisting acute or chronic sleep debt (TSD, 0.23%; CSR, 0.7%). Thus, although sleep debt may be predicted to increase the incidence of concussive injury, the present data suggest that sleep debt does not exacerbate the resulting neuronal damage.

Behavioral sleep-wake homeostasis and EEG delta power are decoupled by chronic sleep restriction in the rat

STUDY OBJECTIVES

Chronic sleep restriction (CSR) is prevalent in society and is linked to adverse consequences that might be ameliorated by acclimation of homeostatic drive. This study was designed to test the hypothesis that the sleep-wake homeostat will acclimatize to CSR.

DESIGN

A four-parameter model of proportional control was used to quantify sleep homeostasis with and without recourse to a sleep intensity function.

SETTING

Animal laboratory, rodent walking-wheel apparatus.

SUBJECTS

Male Sprague-Dawley rats.

INTERVENTIONS

Acute total sleep deprivation (TSD, 1 day × 18 or 24 h, N = 12), CSR (10 days × 18 h TSD, N = 5, or 5 days × 20 h TSD, N = 6).

MEASUREMENTS AND RESULTS

Behavioral rebounds were consistent with model predictions for proportional control of cumulative times in wake, nonrapid eye movement (NREM) and rapid eye movement (REM). Delta (D) energy homeostasis was secondary to behavioral homeostasis; a biphasic NREM D power rebound contributed to the dynamics (rapid response) but not to the magnitude of the rebound in D energy. REM behavioral homeostasis was little affected by CSR. NREM behavioral homeostasis was attenuated in proportion to cumulative NREM deficit, whereas the biphasic NREM D power rebound was only slightly suppressed, indicating decoupled regulatory mechanisms following CSR.

CONCLUSIONS

We conclude that sleep homeostasis is achieved through behavioral regulation, that the NREM behavioral homeostat is susceptible to attenuation during CSR and that the concept of sleep intensity is not essential in a model of sleep-wake regulation.

STUDY OBJECTIVES

Chronic sleep restriction (CSR) is prevalent in society and is linked to adverse consequences that might be ameliorated by acclimation of homeostatic drive. This study was designed to test the hypothesis that the sleep-wake homeostat will acclimatize to CSR.

DESIGN

A four-parameter model of proportional control was used to quantify sleep homeostasis with and without recourse to a sleep intensity function.

SETTING

Animal laboratory, rodent walking-wheel apparatus.

SUBJECTS

Male Sprague-Dawley rats.

INTERVENTIONS

Acute total sleep deprivation (TSD, 1 day × 18 or 24 h, N = 12), CSR (10 days × 18 h TSD, N = 5, or 5 days × 20 h TSD, N = 6).

MEASUREMENTS AND RESULTS

Behavioral rebounds were consistent with model predictions for proportional control of cumulative times in wake, nonrapid eye movement (NREM) and rapid eye movement (REM). Delta (D) energy homeostasis was secondary to behavioral homeostasis; a biphasic NREM D power rebound contributed to the dynamics (rapid response) but not to the magnitude of the rebound in D energy. REM behavioral homeostasis was little affected by CSR. NREM behavioral homeostasis was attenuated in proportion to cumulative NREM deficit, whereas the biphasic NREM D power rebound was only slightly suppressed, indicating decoupled regulatory mechanisms following CSR.

CONCLUSIONS

We conclude that sleep homeostasis is achieved through behavioral regulation, that the NREM behavioral homeostat is susceptible to attenuation during CSR and that the concept of sleep intensity is not essential in a model of sleep-wake regulation.

The impact of hospice services in the care of patients with advanced stage non-small cell lung cancer

104

Background: Prior research has shown that early incorporation of palliative care alongside standard oncological care in metastatic non-small cell lung cancer (NSCLC) patients results in longer survival and less aggressive treatment at the end of life. The purpose of our study was to profile the continuum of care of stage IV NSCLC patients, comparing it to quality indicators for excellence in end-of-life (EOL) cancer care, as defined by the Quality Oncology Practice Initiative and other published studies. Specifically, our aim was to explore the connection between hospice enrollment and end-of-life quality measures. Methods: 197 deceased stage IV NSCLC patients diagnosed between 2008 and 2010 at two separate tertiary care centers within the same county were identified. A retrospective review was conducted, collecting data from electronic medical records regarding antitumor treatment services received, post-diagnosis hospital admissions, palliative care consultations, hospice referrals and enrollments, and circumstances surrounding the patient’s death. The patients were separated into two groups depending on their status of hospice enrollment, and the remainder of the measures compared accordingly. Results: There was no significant difference in number of lines of chemotherapy received and total number of post-diagnosis hospital admissions between the patients who were enrolled in hospice and those who were not. However, the group who received hospice services had a significantly lower number of hospitalizations in the last 30 days of life (p<0.001), emergency department admissions in the last 30 days of life (p<0.01), and intensive care unit admissions in the last 30 days of life (p<0.001). Median survival, measured by the length of time between diagnosis and death, did not differ between the two groups. Conclusions: This study demonstrates that, among patients with metastatic NSCLC, hospice enrollment was associated with optimized end-of-life oncological care, as seen with fewer hospital admissions in the last 30 days of life, without incurring a lower median survival.

Drosophila melanogaster: a fly through its history and current use

Drosophila melanogaster, the common fruit fly, has been used as a model organism in both medical and scientific research for over a century. Work by Thomas Hunt Morgan (1866-1945) and his students at Columbia University at the beginning of the twentieth century led to great discoveries such as sex-linked inheritance and that ionising radiation causes mutations in genes. However, the use of Drosophila was not limited to genetic research. Experimentation with this model organism has also led to discoveries in neuroscience and neurodevelopment, including the basis of circadian rhythms. Its complex nervous system, conserved neurological function, and human disease-related loci allow Drosophila to be an ideal model organism for the study of neurodegenerative disease, for which it is used today, aiding research into diseases such as Alzheimer's and Parkinson's, which are becoming more prevalent in today's ageing population.

Statistical properties of sleep-wake behavior in the rat and their relation to circadian and ultradian phases

STUDY OBJECTIVES

To examine the statistical characteristics of short-term sleep-wake architecture and to evaluate their dependence on ultradian and circadian phase.

DESIGN

Observational, time series.

SETTING

Laboratory.

PARTICIPANTS

Ten male adult Sprague-Dawley rats.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

States of wakefulness (WAKE), rapid eye movement sleep (REM) and nonrapid eye movement sleep (NREM) were recorded in 5-sec epochs over 7 consecutive days. State bout durations were analyzed using parametric regression of survival curves, comparing exponential, biexponential, and power law models. WAKE survival curves were best fit by biexponential models, suggesting that there are two statistically distinct stochastic mechanisms generating two types of WAKE--"brief" WAKE and "long" WAKE. Exponential time constants varied as a function of circadian and ultradian phase, with "long" WAKE showing the largest effect. NREM survival curves exhibited biexponential and monoexponential distributions in light and dark, respectively, with weak effects of ultradian phase. REM survival curves approximated a monoexponential distribution that varied with circadian but not ultradian phase. χ(2) analysis was used in a three-state Markov model to evaluate whether conditional state transition probabilities exhibit the property of first-order dependence. This was partially confirmed, but only after accounting for heterogeneity associated with circadian and ultradian phase. However, there was evidence of residual second-order dependence indicating that additional sources of statistical heterogeneity may remain to be identified.

CONCLUSIONS

Sleep-wake state is regulated over short timescales by stochastic mechanisms. When the major sources of heterogeneity are taken into account, including two-component WAKE and NREM states, the sleep-wake system of the rat behaves, to a reasonable approximation, as a Markovian system that is modulated over ultradian and circadian timescales.

A simple model for the origin of quasiperiodic ultradian rhythms in sleep-wake state in the rat

In a recent study,¹ ultradian rhythms of rat sleep-wake behavior were found, using several methods of time series analysis, to be “quasiperiodic.” That is, ultradian period varied apparently randomly around a mean of approximately 4 h, with no relationship between ultradian period and time of day. Here it is proposed that a simple two-oscillator model can explain the quasiperiodic characteristic of these rhythms. Specifically, in this model a periodic oscillator interacts with a stochastic oscillator to generate a behavioral pattern in which the period and amplitude of the simulated ultradian waves vary randomly around an average value. Preliminary simulations support the plausibility of the model; simulated waveforms were closely similar to behavior patterns observed in adult male rats. It is hypothesized that ultradian rhythms in sleep-wake behavior may arise from a periodic feedback loop (e.g., the sleep-wake homeostat) coupled to a stochastic sleep-wake “flip-flop” switch.

Sleep-wake behavior in the rat: ultradian rhythms in a light-dark cycle and continuous bright light

Ultradian rhythms are a prominent but little-studied feature of mammalian sleep-wake and rest-activity patterns. They are especially evident in long-term records of behavioral state in polyphasic animals such as rodents. However, few attempts have been made to incorporate ultradian rhythmicity into models of sleep-wake dynamics, and little is known about the physiological mechanisms that give rise to ultradian rhythms in sleep-wake state. This study investigated ultradian dynamics in sleep and wakefulness in rats entrained to a 12-h:12-h light-dark cycle (LD) and in rats whose circadian rhythms were suppressed and free-running following long-term exposure to uninterrupted bright light (LL). We recorded sleep-wake state continuously for 7 to 12 consecutive days and used time-series analysis to quantify the dynamics of net cumulative time in each state (wakefulness [WAKE], rapid eye movement sleep [REM], and non-REM sleep [NREM]) in each animal individually. Form estimates and autocorrelation confirmed the presence of significant ultradian and circadian rhythms; maximum entropy spectral analysis allowed high-resolution evaluation of multiple periods within the signal, and wave-by-wave analysis enabled a statistical evaluation of the instantaneous period, peak-trough range, and phase of each ultradian wave in the time series. Significant ultradian periodicities were present in all 3 states in all animals. In LD, ultradian range was approximately 28% of circadian range. In LL, ultradian range was slightly reduced relative to LD, and circadian range was strongly attenuated. Ultradian rhythms were found to be quasiperiodic in both LD and LL. That is, ultradian period varied randomly around a mean of approximately 4 h, with no relationship between ultradian period and time of day.

Tunneling through superlattices: the effect of anisotropy and kinematic coupling

The tunneling of carriers in stratified superlattice systems is analyzed in terms of the constituent effective mass tensor. The focus is on the effects on the tunneling which are caused by the side regions of an intervening barrier. Depending on the covalency and work function in the constituent layers of a superlattice, it is concluded that the kinematics in the regions on either side determined by the effective carrier mass and its interference with the band offset at heterojunctions leads to either a constructive or a destructive effect on the tunneling current. As an example, Si(1-x)Ge(x)/Si and Al(x)Ga(1-x)As/GaAs superlattices are demonstrated to reduce the tunneling current at certain fractional thicknesses and stoichiometries of the constituent slabs without affecting the lateral mobility. The findings show, in general, how manipulation of the carrier's effective mass tensor through stoichiometric/structural modulation of the heterostructure may be used to control the tunneling current through a given potential barrier, given that the characteristic de Broglie wavelength exceeds all the constituent dimensions, thus offering a method complementary to high-k technologies.

What activities do patients with patellar instability perceive makes their patella unstable?

Patellar instability is a disabling musculoskeletal condition. Whilst previous texts have suggested that twisting activities may cause patients to experience instability symptoms, no studies have assessed which activities are related to the patient's perceived instability. The purpose of this study was to determine which activities and with what frequency patients with patellar instability symptoms, perceive their patella to be unstable. Ninety patients referred because of recurrent patellar instability were asked to assess the frequency with which they perceived patellar instability for 19 everyday and sporting activities. The results indicated that sporting and multi-directional twisting activities were more frequently related to patellar instability symptoms, compared to lower energy, uni-planar activities. Females and those without a family history of patellar instability reported more frequent patellar instability symptoms, compared to males, or those with a family history of this disorder. Further study is now recommended to determine whether these results reflect that of patients with milder subluxation disorders, and whether factors such as hypermobility have an impact on perceived patellar instability for this patient group.

Sleep homeostasis: Progress at a snail's pace

We recently reported that a gastropod mollusc, Lymnaea stagnalis, exhibits a sleep-like quiescent state. However quiescence differed from mammalian sleep in that both circadian and homeostatic regulation seemed to be absent in the snail. In the present paper I explore the possibility that the clustered pattern of quiescence observed in the snail may provide insight into underlying regulatory mechanisms. Specifically, I hypothesize that clustering of quiescence arises from feedback modulation of a stochastic wake-quiescence oscillator. The feedback loop is postulated to limit cumulative wakefulness and to exert probabilistic modulation of wake duration. Computer simulations using this model succeeded in simulating snail wake-quiescence behavior, confirming the plausibility of the hypothesis. Implications of this analysis for our understanding of mechanisms and evolution of sleep homeostasis are discussed.

Knowledge, attitudes and behaviours associated with the provision of hepatitis C care by Canadian family physicians

The role of primary care physicians in providing care for hepatitis C virus (HCV) infection is increasingly emphasized, but many gaps and challenges remain. This study explores family physicians' knowledge, attitudes and practices associated with providing care for HCV infection. Seven hundred and forty-nine members of the College of Family Physicians of Canada (CFPC) completed a self-administered survey examining knowledge, attitudes and behaviours regarding HCV infection screening and care. Multivariate analyses were performed using the outcome, HCV care provision, and variables based on a conceptual model of practice guideline adherence. Family physicians providing basic-advanced HCV care were more likely to be older, practice in a rural setting, have injection drug users (IDU) in their practice and have higher levels of knowledge about the initial assessment (OR = 1.77; 95% CI = 1.23-2.54) and treatment of HCV (OR = 1.74; 95% CI = 1.24-2.43). They were also less likely to believe that family physicians do not have a role in HCV care (OR = 0.41; 95% CI = 0.30-0.58). Educational programmes should target physicians less likely to provide HCV care, namely family physicians practicing in urban areas and those who do not care for any IDU patients. Training and continuing medical education programmes that aim to shift family physicians' attitudes about the provision of HCV care by promoting their roles as integral to HCV care could contribute to easing the burden on consultant physicians and lead to improved access to treatment for HCV infection.

Behavioural evidence for a sleep-like quiescent state in a pulmonate mollusc, Lymnaea stagnalis (Linnaeus)

The objective of this study was to determine whether the great pond snail, Lymnaea stagnalis, expresses a sleep-like behavioural state. We found that snails spontaneously enter a relatively brief (22±1 min) quiescent state characterized by postural relaxation of the foot, mantle and tentacles, and cessation of radula rasping. Quiescence was reversed ('aroused') by appetitive (sucrose solution) and aversive (tactile) stimuli. Responsiveness to both stimuli was significantly lower in quiescent snails than in active snails. However, tactile stimuli evoked a more sustained defensive response in quiescent snails. Quiescence bouts were consolidated into 'clusters' over an infradian timescale and were only weakly affected by time of day. Clusters contained 7±0.5 bouts, lasted 13±1 h and were separated by long (37±4 h) intervals of almost continuous activity. Analysis of Kaplan-Meier survival curves revealed that the quiescent bout duration was described by an exponential probability distribution (time constant 15±1 min). Active bout duration was described by a bi-exponential probability distribution (time constants 62±4 and 592±48 min). We found no evidence for a 'sleep rebound' mechanism and quiescence expression appeared to be regulated through stochastic processes causing state transitions to resemble a Markovian random walk. We conclude that Lymnaea is a potentially valuable model system for studies of cellular function in sleep.

A national survey of the physiotherapy management of patients following first-time patellar dislocation

OBJECTIVES

The purpose of this study was to determine how musculoskeletal physiotherapists in acute National Health Service (NHS) hospitals manage patients following a first time patellar dislocation.

DESIGN

National survey study.

SETTING

All NHS acute hospitals with an accident and emergency and/or an orthopaedic department were surveyed.

PARTICIPANTS

306 institutions were surveyed.

INTERVENTIONS

Each institution was sent a 14 question self-administered questionnaire pertaining to the assessment, treatment, evaluation and outcome of patients following a first time patellar dislocation. After 3 weeks, all non-respondents were sent a reminder letter. After a further 3 weeks, those who had not responded by this time were sent a final reminder and copy of the questionnaire.

RESULTS

The survey response rate was 59%. The respondents indicated that first-time patellar dislocation was not a common musculoskeletal disorder managed by NHS physiotherapists, constituting an average of 2% of caseloads. The results suggested that physiotherapists most commonly assess for reduced quadriceps or VMO capacity, gait, patellar tracking and glide, and knee effusion when examining patients following a first-time patellar dislocation. The most common treatments adopted are reassurance, behaviour modification followed by proprioceptive, knee mobility, quadriceps and specific VMO exercises.

CONCLUSIONS

Generic lower limb assessment and treatment strategies are widely used to manage this patient group. Given the previous paucity in this literature, further study is now recommended to assess the efficacy of these interventions to provide UK physiotherapists with an evidence-base to justify their management strategies.

Energy expenditure is affected by rate of accumulation of sleep deficit in rats

STUDY OBJECTIVES

Short sleep is a putative risk factor for obesity. However, prolonged total sleep deprivation (TSD) leads to negative energy balance and weight loss in rodents, whereas sleep-restricted humans tend to gain weight. We hypothesized that energy expenditure (VO2) is influenced by the rate of accumulation of sleep deficit in rats.

DESIGN AND INTERVENTION

Six Sprague-Dawley rats underwent chronic sleep-restriction (CSR, 6-h sleep opportunity at ZT0-6 for 10 days) and stimulus-control protocols (CON, 12-h sleep opportunity for 10 days, matched number of stimuli) in a balanced cross-over design. Four additional rats underwent TSD (4 days). Sleep was manipulated using a motor-driven walking wheel.

MEASUREMENTS AND RESULTS

Electroencephalography, electromyography, and body temperature were measured by telemetry, and VO2, by respirometry. Total sleep deficits of 55.1 +/- 6.4 hours, 31.8 +/- 6.8 hours, and 38.2 +/- 2.3 hours accumulated over the CSR, CON, and TSD protocols, respectively. Responses to TSD confirmed previous reports of elevated VO2 and body temperature. These responses were attenuated in CSR, despite a greater cumulative sleep deficit. Rate of rise of VO2 was strongly correlated with rate of accumulation of sleep deficit, above a threshold deficit of 3.6 h x day(-1).

CONCLUSION

The change in VO2 is affected by rate of accumulation of sleep deficit and not the total sleep loss accrued. Negative energy balance, observed during TSD, is strongly attenuated when brief daily sleep opportunities are available to rats (CSR), despite greater accumulated sleep deficit.

A quasi-experimental feasibility study to determine the effect of a systematic treatment programme on the scores of the Nottingham Adjustment Scale of individuals with visual field deficits following stroke

OBJECTIVE

To evaluate a systematic treatment programme developed by the researcher that targeted aspects of visual functioning affected by visual field deficits following stroke.

DESIGN

The study design was a non-equivalent control (conventional) group pretest-posttest quasi-experimental feasibility design, using multisite data collection methods at specified stages.

SETTING

The study was undertaken within three acute hospital settings as outpatient follow-up sessions.

SUBJECTS

Individuals who had visual field deficits three months post stroke were studied.

INTERVENTIONS

A treatment group received routine occupational therapy and an experimental group received, in addition, a systematic treatment programme. The treatment phase of both groups lasted six weeks.

MAIN MEASURES

The Nottingham Adjustment Scale, a measure developed specifically for visual impairment, was used as the primary outcome measure.

RESULTS

The change in Nottingham Adjustment Scale score was compared between the experimental (n = 7) and conventional (n = 8) treatment groups using the Wilcoxon signed ranks test. The result of Z = -2.028 (P = 0.043) showed that there was a statistically significant difference between the change in Nottingham Adjustment Scale score between both groups.

CONCLUSIONS

The introduction of the systematic treatment programme resulted in a statistically significant change in the scores of the Nottingham Adjustment Scale.