Primary care usage at the end of life: a retrospective cohort study of cancer patients using linked primary and hospital care data

PURPOSE

Health service use is most intensive in the final year of a person's life, with 80% of this expenditure occurring in hospital. Close involvement of primary care services has been promoted to enhance quality end-of-life care that is appropriate to the needs of patients. However, the relationship between primary care involvement and patients' use of hospital care is not well described. This study aims to examine primary care use in the last year of life for cancer patients and its relationship to hospital usage.

METHODS

Retrospective cohort study in Victoria, Australia, using linked routine care data from primary care, hospital and death certificates. Patients were included who died related to cancer between 2008 and 2017.

RESULTS

A total of 758 patients were included, of whom 88% (n = 667) visited primary care during the last 6 months (median 9.1 consultations). In the last month of life, 45% of patients were prescribed opioids, and 3% had imaging requested. Patients who received home visits (13%) or anticipatory medications (15%) had less than half the median bed days in the last 3 months (4 vs 9 days, p < 0.001, 5 vs 10 days, p = 0.001) and 1 month of life (0 vs 2 days, p = 0.002, 0 vs 3 days, p < 0.001), and reduced emergency department presentations (32% vs 46%, p = 0.006, 31% vs 47% p < 0.001) in the final month.

CONCLUSION

This study identifies two important primary care processes-home visits and anticipatory medication-associated with reduced hospital usage and intervention at the end of life.

Sustainable micropollutant bioremediation via stormwater biofiltration system

Waters contaminated with micropollutants are of environmental and public health concern globally. Stormwater is a significant source of anthropogenic micropollutants to receiving waters. Hence, sustainable stormwater remediation is needed to reduce contamination of waterways. Yet designing sustainable bioremediation solutions, including those targeted to remove micropollutants, is a major scientific challenge. This study aimed to adapt the design of stormwater biofiltration systems, to improve the removal of micropollutants and understand the role of the micropollutant-degrading bacteria in this bioremediation process. We investigated the atrazine removal performance of a prototype biofiltration system, in which the filter media was supplemented with Granulated Activated Carbon (GAC). The prototype biofiltration system completely removed atrazine to below detectable limits, significantly exceeding the GAC's adsorption capacity alone, suggesting other biological processes were present. We showed that atrazine degradation capacity, measured by the kinetics of the trzN gene abundance, was accelerated in the prototype system compared to the standard system (which had no added GAC; 0.8 vs. 0.37 week-1, respectively). Notably, this high level of atrazine removal did not come at the expense of the removal performance of other typical stormwater macropollutants (e.g., nutrients, suspended solids). The prototype biofiltration system showed a proof-of-concept of sustaining microbial remediation of a model micropollutant alongside stormwater macropollutants, which could be used to reduce impacts on receiving waterways and protect our ecosystems and human health.

High prevalence of vertebral fractures in seizure patients with normal bone density receiving chronic anti-epileptic drugs

People with epilepsy who take certain medications are at risk for developing osteoporosis and fractures of the vertebrae that commonly go undiagnosed. By using technology available in a bone density scan, we observed at least one fracture in many subjects with bone density in the normal and osteopenic range.

PURPOSE/INTRODUCTION

Chronic use of antiepileptic drugs (AEDs), both enzyme-inducing (phenytoin, phenobarbital, carbamazepine, and primidone) and non-enzyme-inducing (i.e., valproate), is recognized as a cause of secondary osteoporosis. Vertebral compression fractures (VF) are the most common type of osteoporotic fractures and may confer an increased risk of future hip, wrist, and vertebral fractures. Vertebral compression fractures in the general population are frequently asymptomatic, and under-diagnosed. The purpose of this study is to describe the prevalence of VF in a cohort of male veterans with epilepsy on chronic AEDs.

METHODS

The cohort for this study consisted of 146 male veterans who carried a diagnosis of epilepsy and were chronic users of AEDs known to cause osteoporosis (phenobarbital, phenytoin, carbamazepine, primidone, and valproate). Chronic AED use was defined as receiving an AED for at least 2 years. Subjects were previously seen in the osteoporosis clinic and had been evaluated by a dual-energy X-Ray absormetry (DXA) instrument including morphometric studies following a standard vertebral fracture assessment (VFA) protocol during the same DXA imaging acquisition session.

RESULTS

The mean age was 63 years. Low bone mineral density defined as osteoporosis or osteopenia was observed in 29% and 43% respectively. We observed at least one VF in 41 % of the subjects who had normal BMD, 54% in the osteopenic range, and 75% in the osteoporotic range.

CONCLUSIONS

By performing a VFA in addition to standard bone densitometric studies, we disclosed a large prevalence of compression fractures in individuals with epilepsy chronically treated with AEDs who had BMDs in the normal and osteopenic ranges. The addition of VFA or other imaging methods to evaluate VF should be included in the evaluation of bone health in individuals with epilepsy receiving AEDs since it may modify treatment recommendations to prevent future osteoporotic fractures.

Investigation of the HotDog patient warming system: detection of thermal gradients

OBJECTIVE

To assess the performance of an active patient-warming device.

MATERIALS AND METHODS

Temperatures of an active patient-warming device (HotDog system) were measured at various time points using an infrared thermometer. The study was conducted in two phases: Phase 1 compared temperatures among four different areas of the warming blanket. Phase 2 compared conditions simulating different scenarios using a weighted patient simulator.

RESULTS

Phase 1: Three out of four positions on the warming blanket had significantly different temperature measurements. Phase 2: Temperature output by the warming blanket was reduced: (1) in the absence of the patient simulator placed across the blanket (-1·9°C, P=0·013); (2) if the patient simulator was placed away from the blanket sensor (-2·0°C, P=0·009); and (3) if there was fluid between the patient simulator and warming blanket (-2·2°C, P=0·004). In a majority of measurements (95%), the set temperature of 43°C on the control unit was not reached (range, 29·8 to 42·9°C) and 2·3% of measurements were higher (range, 43·1 to 45·8°C) than the control unit set temperature of 43°C.

CLINICAL SIGNIFICANCE

Measured temperatures on the active warming blanket did not reflect control unit settings. This could result in the potential for hyperthermic injury, ineffectual heating and uneven heat distribution.

Peptide and nucleic acid-directed self-assembly of cationic nanovehicles through giant unilamellar vesicle modification: Targetable nanocomplexes for in vivo nucleic acid delivery

One of the greatest challenges for the development of genetic therapies is the efficient targeted delivery of therapeutic nucleic acids. Towards this goal, we have introduced a new engineering initiative in self-assembly of biologically safe and stable nanovesicle complexes (∼90 to 140nm) derived from giant unilamellar vesicle (GUV) precursors and comprising plasmid DNA or siRNA and targeting peptide ligands. The biological performance of the engineered nanovesicle complexes were studied both in vitro and in vivo and compared with cationic liposome-based lipopolyplexes. Compared with cationic lipopolyplexes, nanovesicle complexes did not show advantages in transfection and cell uptake. However, nanovesicle complexes neither displayed significant cytotoxicity nor activated the complement system, which are advantageous for intravenous injection and tumour therapy. On intravenous administration into a neuroblastoma xenograft mouse model, nanovesicle complexes were found to distribute throughout the tumour interstitium, thus providing an alternative safer approach for future development of tumour-specific therapeutic nucleic acid interventions. On oropharyngeal instillation, nanovesicle complexes displayed better transfection efficiency than cationic lipopolyplexes. The technological advantages of nanovesicle complexes, originating from GUVs, over traditional cationic liposome-based lipopolyplexes are discussed.

STATEMENT OF SIGNIFICANCE

The efficient targeted delivery of nucleic acids in vivo provides some of the greatest challenges to the development of genetic therapies. Giant unilamellar lipid vesicles (GUVs) have been used mainly as cell and tissue mimics and are instrumental in studying lipid bilayers and interactions. Here, the GUVs have been modified into smaller nanovesicles. We have then developed novel nanovesicle complexes comprising self-assembling mixtures of the nanovesicles, plasmid DNA or siRNA, and targeting peptide ligands. Their biophysical properties were studied and their transfection efficiency was investigated. They transfected cells efficiently without any associated cytotoxicity and with targeting specificity, and in vivo they resulted in very high and tumour-specific uptake and in addition, efficiently transfected the lung. The peptide-targeted nanovesicle complexes allow for the specific targeted enhancement of nucleic acid delivery with improved biosafety over liposomal formulations and represent a promising tool to improve our arsenal of safe, non-viral vectors to deliver therapeutic cargos in a variety of disorders.

Comparative summer dynamics of surface cyanobacterial communities in two connected lakes from the west of Ireland

The eutrophication of lakes is typically associated with high biomass proliferations of potentially toxic cyanobacteria. At a regional level, the sustainable management of water resources necessitates an approach that recognises the interconnectivity of multiple water systems within river catchments. This study examined the dynamics in summer diversity of planktonic cyanobacterial communities and microcystin toxin concentrations in two inter-connected lakes from the west of Ireland prone to nutrient enrichment. DGGE analysis of 16S rRNA gene amplicons of genotype-I cyanobacteria (typically spherical) showed changes in the communities of both Lough Corrib and Ballyquirke Lough throughout the summer, and identified cyanobacterial genotypes both unique and shared to both lakes. Microcystin concentrations, estimated via the protein phosphatase 2A inhibition assay, were greater in August than in July and June in both lakes. This was concomitant to the increased occurrence of Microcystis as evidenced by DGGE band excision and subsequent sequencing and BLAST analysis. RFLP analysis of PCR amplified mcy-A/E genes clustered together the August samples of both lakes, highlighting a potential change in microcystin producers across the two lakes. Finally, the multiple factor analysis of the combined environmental data set for the two lakes highlighted the expected pattern opposing greater water temperature and chlorophyll concentration against macronutrient concentrations, but also indicated a negative relationship between microcystin concentration and cyanobacterial diversity, possibly underlining allelopathic interactions. Despite some element of connectivity, the dissimilarity in the composition of the cyanobacterial assemblages and the timing of community change in the two lakes likely were a reflexion of niche differences determined by meteorologically-forced variation in physico-chemical parameters in the two water bodies.

A review of recent advances in optical fibre sensors for in vivo dosimetry during radiotherapy

This article presents an overview of the recent developments and requirements in radiotherapy dosimetry, with particular emphasis on the development of optical fibre dosemeters for radiotherapy applications, focusing particularly on in vivo applications. Optical fibres offer considerable advantages over conventional techniques for radiotherapy dosimetry, owing to their small size, immunity to electromagnetic interferences, and suitability for remote monitoring and multiplexing. The small dimensions of optical fibre-based dosemeters, together with being lightweight and flexible, mean that they are minimally invasive and thus particularly suited to in vivo dosimetry. This means that the sensor can be placed directly inside a patient, for example, for brachytherapy treatments, the optical fibres could be placed in the tumour itself or into nearby critical tissues requiring monitoring, via the same applicators or needles used for the treatment delivery thereby providing real-time dosimetric information. The article outlines the principal sensor design systems along with some of the main strengths and weaknesses associated with the development of these techniques. The successful demonstration of these sensors in a range of different clinical environments is also presented.

Progress toward developing a cataract classification system

A cataract classification system is being developed based on a set of standard photographs. The system uses an ordinal scale ranging from 0 (no opacities) to 2 (definite opacities) to classify cataractous changes in the nuclear, cortical, and posterior subcapsular lens zones. The reproducibility of slitlamp-derived and photo-derived classifications using the system was evaluated. The reproducibility between 2 observers for slitlamp-derived classifications was very high (n = 60). The reproducibility within and among 4 photography readers was also good for photo-derived classifications (n = 100). Discrepancies were found between ratings derived from slitlamp examinations and from photographs; such discrepancies were most frequent for gradings of cortical opacities.

Multiphoton luminescence imaging of chemically functionalized multi-walled carbon nanotubes in cells and solid tumors

A simplified scheme showing the non-linear photoluminescence properties of f-MWNTs and their potential use as imaging tools in cells and tumors.

Sewage pollution in urban stormwater runoff as evident from the widespread presence of multiple microbial and chemical source tracking markers

The concurrence of human sewage contamination in urban stormwater runoff (n=23) from six urban catchments across Australia was assessed by using both microbial source tracking (MST) and chemical source tracking (CST) markers. Out of 23 stormwater samples human adenovirus (HAv), human polyomavirus (HPv) and the sewage-associated markers; Methanobrevibacter smithii nifH and Bacteroides HF183 were detected in 91%, 56%, 43% and 96% of samples, respectively. Similarly, CST markers paracetamol (87%), salicylic acid (78%) acesulfame (96%) and caffeine (91%) were frequently detected. Twenty one samples (91%) were positive for six to eight sewage related MST and CST markers and remaining two samples were positive for five and four markers, respectively. A very good consensus (>91%) observed between the concurrence of the HF183, HAv, acesulfame and caffeine suggests good predictability of the presence of HAv in samples positive for one of the three markers. High prevalence of HAv (91%) also suggests that other enteric viruses may also be present in the stormwater samples which may pose significant health risks. This study underscores the benefits of employing a set of MST and CST markers which could include monitoring for HF183, adenovirus, caffeine and paracetamol to accurately detect human sewage contamination along with credible information on the presence of human enteric viruses, which could be used for more reliable public health risk assessments. Based on the results obtained in this study, it is recommended that some degree of treatment of captured stormwater would be required if it were to be used for non-potable purposes.

Electromagnetic transition rates in 100,101Pd using the Recoil Doppler Shift Technique

The quadrupole deformations for the low-lying states in the transitional nuclei 100,101Pd have been deduced through the measurement of their electric quadrupole transition probabilities using the Recoil Distance Doppler Shift Method. The nuclei were studied using a 268 MeV 80Se beam impinging on a thin, self-supporting 24Mg target. States in 100Pd and 101Pd populated by the four and three neutron evaporation channels respectively, with reaction gamma-rays detected using the SPEEDY gamma-ray detection array. The recoiling nuclei were stopped in a copper foil and gamma-ray coincidence data taken at 10 separate target-stopper distances between 35 μm and 750 μm. The mean-lifetimes for the lowest lying 2+ (in 100Pd) and 15/2- (in 101Pd) states were measured to be 13.3(9) ps and 10.8(8) ps respectively. These data are compared with predictions from nuclear Total Routhian Surface calculations, which are found to agree with the experimentally deduced values to within 10%.

Component probability and component reinforcer rate as biasers of free-operant detection

Six pigeons were trained on multiple schedules whose components were concurrent variable-interval extinction and concurrent extinction variable-interval schedules. In Experiments 1a and 1b the stimuli signaling the components were two different light intensities, and in Experiments 2a and 2b they were two identical intensities. The components of the multiple schedule changed probabilistically after each reinforcer. In Experiments 1a and 2a, the probability of presenting the components was varied over five conditions and a replication. In Experiments 1b and 2b, the component probability was .5 and the component reinforcer rates were varied systematically over five conditions and a replication. The data, analyzed according to the Davison-Tustin behavioral detection model, confirmed that the discriminability of the stimuli signaling the components was high when the stimuli were different, and low when the stimuli were the same. Discriminability, measured by log d, was unaffected by component probability variation and by component reinforcer-rate variation. When discriminability was high, bias, or the response allocation between the two keys, was more strongly affected by variation of reinforcer rate within components than by variation of component probability, but the reverse was found when discriminability was low. The results suggest that free-operant detection performance is controlled by the rates of reinforcers in periods of time in which stimuli signal differential contingencies. These periods comprise the components when the component stimuli are discriminable, and comprise the total session when the components are indiscriminable. An extension of the Davison-Tustin behavioral detection model that incorporates these results is presented.

A quantitative analysis of chain-schedule performance

Six pigeons were trained with a chain variable-interval variable-interval schedule on the left key and with reinforcers available on the right key on a single variable-interval schedule arranged concurrently with both links of the chain. All three schedules were separately and systematically varied over a wide range of mean intervals. During these manipulations, the obtained reinforcer rates on constant arranged schedules also frequently changed systematically. Increasing reinforcer rates in Link 2 of the chain increased response rates in both links and decreased response rates in the variable-interval schedule concurrently available with Link 2. Increasing Link-1 reinforcer rates increased Link-1 response rates and decreased Link-2 response rates. Increasing reinforcer rates on the right-key schedule decreased response rates in Link 1 of the chain but did not affect the rate in Link 2. The results extend and amplify previous analyses of chain-schedule performance and help define the effects that a quantitative model must describe. However, the complexity of the results, and the fact that constant arranged reinforcer schedules did not necessarily lead to constant obtained reinforcer rates, precluded a quantitative analysis.

Delayed matching-to-sample performance: Effects of relative reinforcer frequency and of signaled versus unsignaled reinforcer magnitudes

Six pigeons were trained on a delayed red-green matching-to-sample task that arranged four delays within sessions. Matching responses intermittently produced either 1.5-s access to food or 4.5-s access to food, and nonmatching responses produced either 1.5-s or 4.5-s blackout. Two phases were conducted: a signaled phase in which the reinforcer magnitudes (small and large) were signaled by houselights (positioned either on the left or right of the chamber), and an unsignaled phase in which there was no correlation between reinforcer magnitude and houselight position. In both phases, the relative frequency with which red and green matching responses produced food was varied across five values. Both matching accuracy and the sensitivity of performance to the distribution of reinforcers for matching responses decreased with increasing delays in both phases. In addition, accuracy and reinforcer sensitivity were significantly lower on signaled small-reinforcer trials compared with accuracy and sensitivity values on signaled large-reinforcer trials and on both types of unsignaled trials. These results are discussed in the context of research on both nonhuman animal and human memory.

Stimulus control and response bias in an analogue prey-detection procedure

The present study compared the performance of 6 pigeons trained to detect luminance differences in two different signal-detection procedures. Exposed to a three-key array, the pigeons were trained to peck the left key when the brighter of two light intensities had been presented on the center key and to peck the right key when the dimmer of two light intensities had been presented on the center key. Procedure A was a standard signal-detection procedure in which left/bright and right/dim responses produced food reinforcement and left/dim and right/bright responses produced periods of timeout. Procedure B was designed to simulate some of the contingencies operating in a prey-detection situation. Left-key responses produced reinforcement following the brighter center-key stimulus and a period of timeout following the dimmer center-key stimulus. Right-key responses always produced a short period of timeout irrespective of the stimulus. Within each procedure, the duration of timeout arranged for false alarms (left/dim responses) was varied between 3 s and 120 s. Measures of accuracy and response bias were compared between the two procedures. The timeout manipulation produced systematic, but relatively small, changes in these measures when right/dim responses (i.e., correct rejections) produced reinforcement (Procedure A). Arranging timeout for right/dim responses in Procedure B produced greater variability in accuracy and response bias than did arranging reinforcement, but this variability was not related to timeout duration. Overall, discrimination accuracy was considerably higher when right/dim responses produced timeout than when they resulted in reinforcement, and accuracy was accompanied by a large bias toward the response associated with reinforcement. These results are consistent with a recently proposed model of signal detection.

Effects of relative reinforcer frequency on complex color detection

Pigeons were trained under a discrete-trials detection procedure in which one of a set of color stimuli was presented on the center key and a single response turned off the stimulus and illuminated two side keys. Single responses to one or the other side key produced occasional reinforcers depending on the value of the color stimulus. In Experiment 1, one color-stimulus set comprised 559, 564, 569, and 574 nm, and right-key pecks were occasionally reinforced following presentations of members of this set. The other stimulus set comprised 579, 584, 589, and 594 nm, and left-key pecks were occasionally reinforced following presentations of members of this set. Across seven experimental conditions, the left/(left + right) relative reinforcer frequency was varied from .1 to .9. In Experiment 2, one stimulus set contained only one member, 574 nm, and right-key responses were occasionally reinforced following its presentation. Over 12 experimental conditions, two manipulations were carried out. First, the number of stimuli comprising the other stimulus set was increased from one (579 nm) to two (579 and 584 nm) to three (579, 584, and 589 nm) and to four (579, 584, 589, and 594 nm), and left-key responses were reinforced occasionally following center-key presentations of members of this set. Second, for each stimulus combination, the left/(left + right) relative reinforcer frequency was varied from .1 to .5 to .9 across three experimental conditions. The principal finding of Experiments 1 and 2 was that reinforcers and stimuli interacted in their effects on behavior. In Experiment 3, pairs of adjacent stimuli (5 nm apart) in the range 559 to 594 nm were presented in each experimental condition, and the left/(left + right) relative reinforcer frequency was held constant at .5. The data from all three experiments were analyzed according to a detection model describing performance in multiple-stimulus two-response procedures. This model provided independent measures of stimulus discriminability, contingency discriminability, and bias. The analysis showed that (a) consistent with the color-naming function, pigeons were better able to discriminate between higher nanometer values than lower nanometer values; (b) their ability to discriminate between the stimuli was independent of the number of wavelengths comprising each stimulus set; (c) they allocated delivered reinforcers very accurately to the previously emitted response; and (d) no consistent biases emerged.

Effects of the discriminability of alternatives in three-alternative concurrent-schedule performance

Six pigeons were trained on two- and three-alternative concurrent schedules in which the alternatives were signaled by different wavelengths of light on the main pecking key. The schedules were arranged according to a switching-key procedure in which pecks on a white side key produced a 3-s blackout and, intermittently, a change in the variable-interval schedule of food programmed on the main (center) key after the blackout. In Part 1, a two-alternative concurrent variable-interval schedule was arranged in which the alternatives were signaled by 560 nm and 630 nm. Parts 2 and 3 arranged three-alternative concurrent variable-interval schedules with the alternatives signaled by 560 nm, 600 nm, and 630 nm (Part 2) and 560 nm, 623 nm, and 630 nm (Part 3). Within each part, the relative rate of food reinforcers available on the alternatives was varied across a wide range. In all parts of the experiment, the ratios of responses emitted between pairs of alternatives were more extreme than the ratios of reinforcers obtained on the pairs of alternatives, a result termed overmatching. In Parts 2 and 3, generalized matching sensitivities between pairs of alternatives were found to be higher when the reinforcer rate on the third alternative was low than when it was high-an apparent failure of the constant-ratio rule. The data were well described by an extension of the Davison and Jenkins (1985) model, which assumes differing discriminabilities between concurrent-schedule alternatives in combination with a punishing effect of blackout following changeovers.

Delayed reinforcement and delayed choice in symbolic matching to sample: Effects on stimulus discriminability

Six pigeons were trained to peck a red side key when the brighter of two white lights (S(1)) had been presented on the center key, and to peck a green side key when the dimmer of two white lights (S(2)) had been presented on the center key. Equal frequencies of reinforcers were provided for the two types of correct choice. Incorrect choices, red side-key pecks following S(2) presentations and green side-key pecks following S(1) presentations, resulted in blackout. With 0-s delay between choice and reinforcement, the delay between sample presentation and choice was varied from 0 to 20 s. Then, with 0-s delay between sample presentation and choice, the delay between choice and reinforcement was varied from 0 to 20 s. Both types of delay resulted in decreased discriminability (defined in terms of a signal-detection analysis) of the center-key stimuli, but delayed choice had more effect on discriminability than did delayed reinforcement. These data are consistent with the view that the two kinds of delay operate differently. The effect of a sample-choice delay may result from a degradation of the conditional discriminative stimuli during the delay; the effect of a choice-reinforcer delay may result from a decrement in control by differential reinforcement.

Reinforcement for errors in a signal-detection procedure

Six pigeons were trained on a signal-detection procedure. They were required to peck the left key when a 5-second white light had been presented, and the right key when a 10-second light had been presented. These two correct responses were followed by food reinforcement with a probability of .7. Errors, left responses after the 10-second stimulus or right responses after the 5-second stimulus, were initially followed by a 3-second blackout of the chamber. In nine subsequent experimental conditions, errors were followed by food reinforcement with increasing probability while the probability of reinforcement for correct responses was kept constant. The percentage of correct responses decreased as error reinforcement probability increased. A matching model of detection performance, in which discrimination is a joint function of stimulus discriminability and stimulus-reinforcement association, provided a convincing fit to the data and to two sets of published data. The model also fitted published data on multiple and multiple-concurrent free-operant performance. This description of detection performance in terms of matching offers both accurate prediction of complex behavior and measures of discriminability with wide generality.

Proteomic profiling of the rat cerebral cortex in sleep and waking

Transcriptomic studies have shown that hundreds of genes change their expression levels across the sleep/waking cycle, and found that waking-related and sleep-related mRNAs belong to different functional categories. Proteins, however, rather than DNA or RNA, carry out most of the cellular functions, and direct measurements of protein levels and activity are required to assess the effects of behavioral states on the overall functional state of the cell. Here we used surface-enhanced laser desorption-ionization (SELDI), followed by time-of-flight mass spectrometry, to obtain a large-scale profiling of the proteins in the rat cerebral cortex whose expression is affected by sleep, spontaneous waking, short (6 hours) and long (7 days) sleep deprivation. Each of the 94 cortical samples was profiled in duplicate on 4 different ProteinChip Array surfaces using 2 different matrix molecules. Overall, 1055 protein peaks were consistently detected in cortical samples and 15 candidate biomarkers were selected for identification based on significant changes in multiple conditions (conjunction analysis): 8 "sleep" peaks, 4 "waking" peaks, and 4 "long sleep deprivation" peaks. Four candidate biomarkers were purified and positively identified. The 3353 Da candidate sleep marker was identified as the 30 amino acid C-terminal fragment of rat histone H4. This region encompasses the osteogenic growth peptide, but a possible link between sleep and this peptide remains highly speculative. Two peaks associated with short and long sleep deprivation were identified as hemoglobin alpha1/2 and beta, respectively, while another peak associated with long sleep deprivation was identified as cytochrome C. The upregulation of hemoglobins and cytochrome C may be part of a cellular stress response triggered by even short periods of sleep loss.

The irony of a rich country: issues of financial access to and availability of healthy food in the Republic of Ireland

OBJECTIVE

To determine the weekly financial cost of a diet as recommended by national policy in two parents with two children, single parents with one child and single old people with low income, and begin to identify, in a rich country context, variation in food item availability, price and household purchasing capacity.

DESIGN

Food baskets were developed based on national dietary recommendations and purchasing patterns of these household groups. National-level prices of each food were identified, as well as pricing across a representative selection of Irish retail outlet types. Basket costs were assessed relative to the financial capacity of household type.

RESULTS

The types of retail outlets in which low-income groups tend to shop do not carry many own brand items and is less likely to stock healthy options, but when they do, they are more expensive than in other outlets. Single parents with one child, two adults with two children and single older people would have to spend 80%, 69% and 38%, respectively, of their weekly household income to purchase the food basket based on economy-line products.

CONCLUSIONS

Financial access to and availability of healthy food options must be considered through a national policy cognisant of basic human needs for healthy living. This research provides evidence on the direct costs of healthy eating for policy and planning to ensure not only financial capacity but also to guarantee that affordable healthy food choices are physically available to all groups in society.

Vitamin D intake and status in Irish elderly women and adolescent girls

AIM

To assess vitamin D status during summer and winter in Irish girls and elderly women, and to estimate vitamin D intake in these two age-groups.

METHODS

Ambulatory free-living, elderly Irish women (aged 70-76 years; n = 43) and girls (aged 11-13 years; n = 17) were recruited. Fasting serums were collected during August/ September 2002 and February/March 2003 and analysed for 25 (OH) D by HPLC.

RESULTS

Mean daily intakes of vitamin D were 4.6 microg and 2.1 microg in elderly women and girls, respectively. Serum 25 (OH) D was significantly lower (P<0.001) during winter than summer in both age-groups. Eight (20%) and one (during late summer) and sixteen (37.2%) and eight (47%) (during late winter) of the elderly women and girls, respectively, had inadequate vitamin D status (serum 25 (OH) D <40 nmol/l).

CONCLUSION

Inadequate vitamin D status during winter time is quite common in elderly women and adolescent girls in Ireland.

Unilateral ocular myasthenia gravis in an acute medical take: is a Tensilon test useful?

A 42-year-old woman presented to an eye clinic with a 2-week history of diplopia. Examination revealed signs of a right sixth nerve palsy. A computed tomography (CT) brain scan was normal. Six weeks later she presented during the acute medical take with increasing diplopia, a drooping right eyelid and unsteadiness. Direct questioning revealed that the drooping became progressively worse throughout the day. She had no relevant past medical history or any regular medication. Examination revealed a partial right ptosis and signs of right third, fourth and sixth nerve palsy. Diplopia on binocular vision resolved on patch testing; neurological examination was otherwise unremarkable, with no evidence of limb weakness.

A magnetic resonance imaging scan of the brain and CSF examination were unremarkable. Ocular myasthenia was suspected, anti-acetylcholine receptor antibody test was requested, and a Tensilon test was performed with full resuscitation equipment available. Following the administration of the test dose (2 mg) of intravenous edrophonium (Tensilon) a visible improvement in the right ptosis was observed. Subsequent administration of a further 8 mg edrophonium yielded more marked improvement, with complete correction of the right ptosis (Figure 1) and a subjective decrease in diplopia on right gaze. A diagnosis of unilateral ocular myasthenia gravis was made on the basis of the clinical picture and the positive Tensilon test.

A neurological opinion was sought and the patient commenced on pyridostigmine 60 mg four times a day. Further investigations included a CT scan of the thorax which revealed a 2 cm retrosternal mass, compatible with thymic hyperplasia. Five weeks after the positive Tensilon test, a report of strongly positive anti-acetylcholine receptor antibodies (anti-acetylcholine receptor antibodies >8 nmol/litre, normal range 0–0.5 nmol/litre) was received. The diplopia continues to improve and the patient has regular follow up.