719 research outputs found
A new species of <i>Syrticola</i> Willems & Claeys, 1982 (Copepoda: Harpacticoida) from Japan with notes on the type species
A new species of Syrticola Willems & Claeys, 1982 (Harpacticoida: Cylindropsyllidae) is described from Okinawa, Japan. Morphological notes on the type species S. flandricus Willems & Claeys, 1982 and a key to the species are given. The inadequately described S. trispinosus A. Scott, 1896 is ranked as species inquirenda. The diagnosis of the genus is amended and its position in the Cylindropsyllidae re-assessed. Both sexes of S. intermedius sp. nov. were found to be infested by early parthenogenetic female stages of an as yet undescribed genus of Tantulocarida
Discovery of hydrothermal vent Tantulocarida on a new genus of Argestidae (Copepoda: Harpacticoida)
Preliminary investigations of hydrothermal vent harpacticoids from the Galapagos Rift resulted in the discovery of a new genus and species of Tantulocarida. Rimitantulus hirsutus gen. et sp. nov. is described on the basis of the tantulus larva and the male at an early stage of development. It is the first record of the subclass from hydrothermal vent habitats and is placed in the Basipodellidae which exclusively utilize copepods as hosts. The harpacticoid host Argestoides prehensilis gen. et sp. nov., which is known only from the male, shows affinities with both the Ameiridae and Argestidae and is placed genus incertae sedis in the latter primarily on account of the complete lack of sexual dimorphism on the swimming legs
Abnormal reward valuation and event-related connectivity in unmedicated major depressive disorder
BACKGROUND: Experience of emotion is closely linked to valuation. Mood can be viewed as a bias to experience positive or negative emotions and abnormally biased subjective reward valuation and cognitions are core characteristics of major depression. METHODS: Thirty-four unmedicated subjects with major depressive disorder and controls estimated the probability that fractal stimuli were associated with reward, based on passive observations, so they could subsequently choose the higher of either their estimated fractal value or an explicitly presented reward probability. Using model-based functional magnetic resonance imaging, we estimated each subject's internal value estimation, with psychophysiological interaction analysis used to examine event-related connectivity, testing hypotheses of abnormal reward valuation and cingulate connectivity in depression. RESULTS: Reward value encoding in the hippocampus and rostral anterior cingulate was abnormal in depression. In addition, abnormal decision-making in depression was associated with increased anterior mid-cingulate activity and a signal in this region encoded the difference between the values of the two options. This localised decision-making and its impairment to the anterior mid-cingulate cortex (aMCC) consistent with theories of cognitive control. Notably, subjects with depression had significantly decreased event-related connectivity between the aMCC and rostral cingulate regions during decision-making, implying impaired communication between the neural substrates of expected value estimation and decision-making in depression. CONCLUSIONS: Our findings support the theory that abnormal neural reward valuation plays a central role in major depressive disorder (MDD). To the extent that emotion reflects valuation, abnormal valuation could explain abnormal emotional experience in MDD, reflect a core pathophysiological process and be a target of treatment
Novel conopeptides of the I-superfamily occur in several clades of cone snails
The I-superfamily of conotoxins represents a new class of peptides in the venom of some Conus species. These toxins are characterized by four disulfide bridges and inhibit or modify ion channels of nerve cells. When testing venoms from 11 Conus species for a functional characterization, blocking activity on potassium channels (like Kv1.1 and Kv1.3 channels, but not Kv1.2 channels) was detected in the venom of Conus capitaneus, Conus miles, Conus vexillum and Conus virgo. Analysis at the cDNA level of these venoms using primers designed according to the amino acid sequence of a potassium channel blocking toxin (ViTx) from C. virgo confirmed the presence of structurally homologous peptides in these venoms. Moreover, peptides belonging to the I-superfamily, but with divergent amino acid sequences, were found in Conus striatus and Conus imperialis. In all cases, the sequences of the precursors' prepro-regions exhibited high conservation, whereas the sequences of the mature peptides ranged from almost identical to highly divergent between species. We then performed phylogenetic analyses of new and published mitochondrial 16S rDNA sequences representing 104 haplotypes from these and numerous other Conus species, using Bayesian, maximum-likelihood, maximum-parsimony and neighbor-joining methods of inference. Cone snails known to possess I-superfamily toxins were assigned to five different major clades in all of the resulting gene trees. Moreover, I-superfamily conopeptides were detected both in vermivorous and piscivorous species of Conus, thus demonstrating the widespread presence of such toxins in this speciose genus beyond evolutionary and ecological groups
Identifying Key Benefits in European Off-Patent Biologics and Biosimilar Markets: It is Not Only About Price!
Biosimilar medicines have shown similarity with the originator biologic and offer a similar clinical outcome generally at a lower cost. This paper identifies benefits of off-patent biologics and biosimilars, and illustrates these benefits with empirical data from Europe. We provide a narrative review of published literature on values and benefits of biosimilars in Europe. The results describe cost savings as the key driver stemming from the lower price of biosimilars, than that of originator products, and from price competition between biosimilar(s), originator, and next-generation products. Cost savings may then translate into a number of other associated benefits. The lower price of biosimilars and similar effectiveness to the originator biologics improve cost effectiveness, implying that reimbursement can be granted or extended to other pa
A comparison of 'pruning' during multi-step planning in depressed and healthy individuals
BACKGROUND: Real-life decisions are often complex because they involve making sequential choices that constrain future options. We have previously shown that to render such multi-step decisions manageable, people 'prune' (i.e. selectively disregard) branches of decision trees that contain negative outcomes. We have theorized that sub-optimal pruning contributes to depression by promoting an oversampling of branches that result in unsavoury outcomes, which results in a negatively-biased valuation of the world. However, no study has tested this theory in depressed individuals. METHODS: Thirty unmedicated depressed and 31 healthy participants were administered a sequential reinforcement-based decision-making task to determine pruning behaviours, and completed measures of depression and anxiety. Computational, Bayesian and frequentist analyses examined group differences in task performance and relationships between pruning and depressive symptoms. RESULTS: Consistent with prior findings, participants robustly pruned branches of decision trees that began with large losses, regardless of the potential utility of those branches. However, there was no group difference in pruning behaviours. Further, there was no relationship between pruning and levels of depression/anxiety. CONCLUSIONS: We found no evidence that sub-optimal pruning is evident in depression. Future research could determine whether maladaptive pruning behaviours are observable in specific sub-groups of depressed patients (e.g. in treatment-resistant individuals), or whether misuse of other heuristics may contribute to depression
Challenges and Solutions to the Measurement of Neurocognitive Mechanisms in Developmental Settings
Identifying early neurocognitive mechanisms that confer risk for mental health problems is one important avenue as we seek to develop successful early interventions. Currently, however, we have limited understanding of the neurocognitive mechanisms involved in shaping mental health trajectories from childhood through young adulthood, and this constrains our ability to develop effective clinical interventions. In particular, there is an urgent need to develop more sensitive, reliable, and scalable measures of individual differences for use in developmental settings. In this review, we outline methodological shortcomings that explain why widely used task-based measures of neurocognition currently tell us little about mental health risk. We discuss specific challenges that arise when studying neurocognitive mechanisms in developmental settings, and we share suggestions for overcoming them. We also propose a novel experimental approach—which we refer to as “cognitive microscopy”—that involves adaptive design optimization, temporally sensitive task administration, and multilevel modeling. This approach addresses some of the methodological shortcomings outlined above and provides measures of stability, variability, and developmental change in neurocognitive mechanisms within a multivariate framework
Learnings from Regional Market Dynamics of Originator and Biosimilar Infliximab and Etanercept in Germany.
Drug budget and prescription control measures are implemented regionally in Germany, meaning that the uptake of pharmaceuticals, including biosimilars, can vary by region. We examine regional market dynamics of tumor necrosis factor alpha (TNFα) inhibitor originators and biosimilars in Germany and studied the influence of biosimilar policies on these dynamics. This study is based on: (1) a literature review in which German biosimilar policies are identified, (2) the analysis of dispensing data (2010-2018) for the class of TNFα inhibitors, and (3) ten semi-structured interviews investigating prescribers' and insurers' views on factors potentially influencing biosimilar uptake. The analysis of biosimilar market shares of infliximab and etanercept revealed wide variations across the 17 German Regional Associations of Statutory Health Insurance Accredited Physicians (PA regions). Quantitative analyses indicated that biosimilar market shares for infliximab and etanercept were significantly lower in former East Germany when compared to former West Germany regions. Through qualitative interview analyses, this study showed that the use of infliximab and etanercept biosimilars across Germany is primarily influenced by (1) the regional-level implementation of biosimilar quotas and the presence of monitoring/sanctioning mechanisms to ensure adherence to these quotas, (2) the different insurer-manufacturer discount contracts, and (3) gainsharing arrangements established at the insurer-prescriber level
From Computation to Clinic
Theory-driven and data-driven computational approaches to psychiatry have enormous potential for elucidating mechanism of disease and providing translational linkages between basic science findings and the clinic. These approaches have already demonstrated utility in providing clinically relevant understanding, primarily via back translation from clinic to computation, revealing how specific disorders or symptoms map onto specific computational processes. Nonetheless, forward translation, from computation to clinic, remains rare. In addition, consensus regarding specific barriers to forward translation—and on the best strategies to overcome these barriers—is limited. This perspective review brings together expert basic and computationally trained researchers and clinicians to 1) identify challenges specific to preclinical model systems and clinical translation of computational models of cognition and affect, and 2) discuss practical approaches to overcoming these challenges. In doing so, we highlight recent evidence for the ability of computational approaches to predict treatment responses in psychiatric disorders and discuss considerations for maximizing the clinical relevance of such models (e.g., via longitudinal testing) and the likelihood of stakeholder adoption (e.g., via cost-effectiveness analyses)
- …