Naturalistic assessment of everyday multitasking in Parkinson's disease with and without mild cognitive impairment.

Multitasking is an essential part of everyday functioning often not formally assessed by traditional neuropsychological tests. Although individuals with Parkinson's disease (PD) experience both motor and cognitive difficulties, previous research has demonstrated more pronounced functional difficulties with the presence of mild cognitive impairment (PD-MCI). The current study compared individuals with PD-MCI, PD with normal cognition (PD-NC), and healthy controls on a naturalistic task of multitasking, the Day Out Task (DOT).

Prospective predictors of care partner burden and depression in Parkinson's disease.

Objectives: Care partners who provide informal care to individuals with Parkinson's disease (PD) report higher levels of burden and depression; however, longitudinal research on these symptoms is scarce. The current study assessed changes in care partner burden and depression, and patient and care partner predictors of these symptoms over time. Such knowledge may provide important information for assessment and treatment of depression and burden in care partners of individuals with PD.

Medication Management Performance in Parkinson's Disease: Examination of Process Errors.

Objective: Individuals with Parkinson's disease (PD) are at risk for increased medication mismanagement, which can lead to worse clinical outcomes. However, the nature of the errors (i.e.

Contrasting responses to salinity and future ocean acidification in arctic populations of the amphipod Gammarus setosus.

Climate change is leading to alterations in salinity and carbonate chemistry in arctic/sub-arctic marine ecosystems. We examined three nominal populations of the circumpolar arctic/subarctic amphipod, Gammarus setosus, along a salinity gradient in the Kongsfjorden-Krossfjorden area of Svalbard. Field and laboratory experiments assessed physiological (haemolymph osmolality and gill Na/K-ATPase activity, NKA) and energetic responses (metabolic rates, MO, and Cellular Energy Allocation, CEA).

Maternal and cohort effects modulate offspring responses to multiple stressors.

Current concerns about climate change have led to intensive research attempting to understand how climate-driven stressors affect the performance of organisms, in particular the offspring of many invertebrates and fishes. Although stressors are likely to act on several stages of the life cycle, little is known about their action across life phases, for instance how multiple stressors experienced simultaneously in the maternal environment can modulate the responses to the same stressors operating in the offspring environment. Here, we study how performance of offspring of a marine invertebrate (shore crab ) changes in response to two stressors (temperature and salinity) experienced during embryogenesis in brooding mothers from different seasons.

Elevated pCO does not impair performance in autotomised individuals of the intertidal predatory starfish Asterias rubens (Linnaeus, 1758).

The impacts of ocean acidification remain less well-studied in starfish compared to other echinoderm groups. This study examined the combined effects of elevated pCO and arm regeneration on the performance of the intertidal predatory starfish Asterias rubens, as both are predicted to come at a cost to the individual. A two-way factorial experiment (~400 μatm vs ~1000 μatm; autotomised vs non-automised individuals) was used to examine growth rates, lipid content (pyloric caeca and gonads), and calcium content (body wall) in both intact and regenerating arms, as well as subsequent effects on rate of arm regeneration, righting time (behaviour) and mortality over 120 days.

Sensitivity to near-future CO conditions in marine crabs depends on their compensatory capacities for salinity change.

Marine crabs inhabit shallow coastal/estuarine habitats particularly sensitive to climate change, and yet we know very little about the diversity of their responses to environmental change. We report the effects of a rarely studied, but increasingly prevalent, combination of environmental factors, that of near-future pCO (~1000 µatm) and a physiologically relevant 20% reduction in salinity. We focused on two crab species with differing abilities to cope with natural salinity change, and revealed via physiological and molecular studies that salinity had an overriding effect on ion exchange in the osmoregulating shore crab, Carcinus maenas.

Loss of glutamate signaling from the thalamus to dorsal striatum impairs motor function and slows the execution of learned behaviors.

Parkinson's disease (PD) is primarily associated with the degeneration of midbrain dopamine neurons, but it is now appreciated that pathological processes like Lewy-body inclusions and cell loss affect several other brain regions, including the central lateral (CL) and centromedian/parafascicular (CM/PF) thalamic regions. These thalamic glutamatergic neurons provide a non-cortical excitatory input to the dorsal striatum, a major projection field of dopamine neurons. To determine how thalamostriatal signaling may contribute to cognitive and motor abnormalities found in PD, we used a viral vector approach to generate mice with loss of thalamostriatal glutamate signaling specifically restricted to the dorsal striatum (CAV2- mice).

Comparison of whole animal costs of protein synthesis among polar and temperate populations of the same species of gammarid amphipod.

Protein synthesis can account for a substantial proportion of metabolic rate. Energetic costs of protein synthesis, should in theory, be the same in marine invertebrates from a range of thermal habitats, and yet direct measurements using inhibitors produce widely differing values, especially in the cold. The present study aimed to remove any potential confounding interspecific effects by determining costs of protein synthesis in two latitudinally separated populations of the same species (amphipod, Gammarus oceanicus) living in two different thermal regimes; polar vs cold-temperate.

The Population Tracking Model: A Simple, Scalable Statistical Model for Neural Population Data.

Our understanding of neural population coding has been limited by a lack of analysis methods to characterize spiking data from large populations. The biggest challenge comes from the fact that the number of possible network activity patterns scales exponentially with the number of neurons recorded ([Formula: see text]). Here we introduce a new statistical method for characterizing neural population activity that requires semi-independent fitting of only as many parameters as the square of the number of neurons, requiring drastically smaller data sets and minimal computation time.

A hidden Markov model for decoding and the analysis of replay in spike trains.

We present a hidden Markov model that describes variation in an animal's position associated with varying levels of activity in action potential spike trains of individual place cell neurons. The model incorporates a coarse-graining of position, which we find to be a more parsimonious description of the system than other models. We use a sequential Monte Carlo algorithm for Bayesian inference of model parameters, including the state space dimension, and we explain how to estimate position from spike train observations (decoding).

Validation of the flooding dose technique to determine fractional rates of protein synthesis in a model bivalve species, the blue mussel (Mytilus edulis L.).

For the first time, use of the flooding dose technique using (3)H-Phenylalanine is validated for measuring whole-animal and tissue-specific rates of protein synthesis in the blue mussel Mytilus edulis (61mm shell length; 4.0g fresh body mass). Following injection, the phenylalanine-specific radioactivities in the gill, mantle and whole-animal free pools were elevated within one hour and remained elevated and stable for up to 6h following injection of (3)H-phenylalanine into the posterior adductor muscle.

Physiological responses to digestion in low salinity in the crabs Carcinus maenas and Cancer irroratus.

Osmoregulation and digestion are energetically demanding, and crabs that move into low salinity environments to feed must be able to balance the demands of both processes. Achieving this balance may pose greater challenges for weak than for efficient osmoregulators. This study examined the rate of oxygen consumption (MO2) of Carcinus maenas (efficient osmoregulator) and Cancer irroratus (weak osmoregulator) as a function of feeding and hyposaline stress.

Ocean warming, more than acidification, reduces shell strength in a commercial shellfish species during food limitation.

Ocean surface pH levels are predicted to fall by 0.3-0.4 pH units by the end of the century and are likely to coincide with an increase in sea surface temperature of 2-4 °C.

Influence of natural thermal gradients on whole animal rates of protein synthesis in marine gammarid amphipods.

Although temperature is known to have an important effect on protein synthesis rates and growth in aquatic ectotherms held in the laboratory, little is known about the effects of thermal gradients on natural populations in the field. To address this issue we determined whole-animal fractional rates of protein synthesis (ks ) in four dominant species of gammarid amphipods with different distributions along the coasts of Western Europe from arctic to temperate latitudes. Up to three populations of each species were collected in the summer and ks measured within 48 h.

Genetic diversity of the feminising microsporidian parasite Dictyocoela: new insights into host-specificity, sex and phylogeography.

Microsporidia of the genus Dictyocoela are parasites of gammarid amphipod Crustacea. They typically exhibit low virulence and efficient vertical transmission and at least some strains are capable of feminising their hosts. Sequencing of a region of the 16S rDNA of Dictyocoela spp.

Congeneric amphipods show differing abilities to maintain metabolic rates with latitude.

Metabolic variability across latitudinal populations of gammarid amphipods was examined in the summer by determining whole-animal rates of oxygen uptake (M(o)₂) in four species with overlapping distribution patterns in the northeast Atlantic and Arctic oceans. Comparisons were made between an arctic/boreal species, Gammarus setosus, a subarctic/boreal species, Gammarus oceanicus, a boreal/temperate species, Gammarus duebeni duebeni, and a temperate species, Gammarus locusta. Measurements included acclimatized M(o)₂ in all four species and M(o)₂ after acclimation to 10°C in two populations of G.

Characterisation of myosin heavy chain gene variants in the fast and slow muscle fibres of gammarid amphipods.

Recent molecular work has revealed a large diversity of myosin heavy chain (MyHC) gene variants in the abdominal musculature of gammarid amphipods. An unusual truncated MyHC transcript from the loop 1 region (Variant A(3)) was consistently observed in multiple species and populations. The current study aimed to determine whether this MyHC variant is specific to a particular muscle fibre type, as a change in net charge to the loop 1 region of Variant A(3) could be functionally significant.

Linking functional molecular variation with environmental gradients: myosin gene diversity in a crustacean broadly distributed across variable thermal environments.

To investigate the molecular basis of temperature adaptation in natural populations we used the candidate gene approach, targeting the myosin heavy chain (MyHC) gene. The functional effects of genetic variation in MyHC have been well characterised, and changes in the flexibility of the surface loops 1 and 2, caused by modulations in length, amino acid composition and charge can play an important role in thermal acclimation in fish. However, the extent that MyHC diversity is influenced by natural thermal gradients is largely unknown.

Effects of salinity on rates of protein synthesis and oxygen uptake in the post-larvae and juveniles of the tropical prawn Macrobrachium rosenbergii (de Man).

Protein synthesis is a major determinant of growth and yet little is known about the environmental factors that influence protein synthesis rates in farmed freshwater prawns. To this end, post-larvae and juveniles of Macrobrachium rosenbergii were exposed to various salinities (0, 14, 30 per thousand) to determine whole-animal rates of fractional protein synthesis (k(s)) and oxygen uptake. In the post-larvae that migrate upstream from brackish to freshwater areas, whole-animal k(s) was unaffected by salinity, but rates of oxygen uptake were significantly lower at 14 per thousand.

Phylogeography and environmental diversification of a highly adaptable marine amphipod, Gammarus duebeni.

Genetic diversity and phylogeographic population structure in the gammarid amphipod, Gammarus duebeni, were investigated across its broad latitudinal distribution in the NE and NW Atlantic by analysis of mitochondrial DNA sequence. Gammarus duebeni has exceptional tolerance of salinity change and inhabits environments ranging from marine to freshwater. The longstanding debate on whether there are distinct marine and freshwater subspecies was assessed by sampling populations from sites characterized by different salinities.

Polar cod, Boreogadus saida (Gadidae), show an intermediate stress response between Antarctic and temperate fishes.

To examine whether the attenuated stress response observed in Antarctic notothenioid fishes is a specialism for life in sub-zero waters, the polar cod, Boreogadus saida, and the temperate shorthorned sculpin, Myoxocephalus scorpius, were subjected to various stress treatments. Activity stress in both species had no effect on plasma catecholamine and cortisol levels, splenic mass, and on the haematological variables in B. saida.

Temperature influences whole-animal rates of metabolism but not protein synthesis in a temperate intertidal isopod.

The effects of temperature on two important biological rate processes, whole-body rates of oxygen uptake (M dot o2) and protein synthesis (k(s)), were investigated in the temperate intertidal isopod Ligia oceanica at two different times of the year. Animals were collected in January (winter) and June (summer) and either subjected to an acute temperature change after 24 h (acclimatized) or acclimated to various temperatures for 4 wk. In both cases, M dot o2 increased with temperature, with a Q(10) of 2.

Do cannabinoid drugs have a therapeutic value as analgesics?

Laboratory research has shown promising results for using plant-derived, synthetic or endogenous cannabinoids for analgesia. However, human studies are few and far between and have been held up by the law and the lack of standardised extracts. This paper considers these drugs' potential uses in pain management.

Ionoregulatory changes in the gill epithelia of coho salmon during seawater acclimation.

Short-term exposure of coho salmon smolts (Oncorhynchus kisutch) to a gradual increase in salinity over 2 d (0 per thousand -32 per thousand ) resulted in a decrease in proton pump abundance, detected as changes in immunoreactivity with a polyclonal antibody against subunit A of bovine brain vacuolar H(+)-ATPase. N-ethylmaleimide (NEM)-sensitive H(+)-ATPase activities in gill homogenates remained unchanged over 8 d to coincide with a 3.5-fold increase in Na(+)/K(+)-ATPase activities.