429 research outputs found
What Difference Does Quantity Make? On the Epistemology of Big Data Biology
publication-status: Acceptedtypes: ArticleIs Big Data science a whole new way of doing research? And what difference does data quantity make to knowledge
production strategies and their outputs? I argue that the novelty of Big Data science does not lie in the sheer quantity of
data involved, but rather in (1) the prominence and status acquired by data as commodity and recognised output, both
within and outside of the scientific community and (2) the methods, infrastructures, technologies, skills and knowledge
developed to handle data. These developments generate the impression that data-intensive research is a new mode of
doing science, with its own epistemology and norms. To assess this claim, one needs to consider the ways in which data
are actually disseminated and used to generate knowledge. Accordingly, this article reviews the development of sophisticated
ways to disseminate, integrate and re-use data acquired on model organisms over the last three decades of work
in experimental biology. I focus on online databases as prominent infrastructures set up to organise and interpret such
data and examine the wealth and diversity of expertise, resources and conceptual scaffolding that such databases draw
upon. This illuminates some of the conditions under which Big Data needs to be curated to support processes of
discovery across biological subfields, which in turn highlights the difficulties caused by the lack of adequate curation for
the vast majority of data in the life sciences. In closing, I reflect on the difference that data quantity is making to
contemporary biology, the methodological and epistemic challenges of identifying and analysing data given these developments,
and the opportunities and worries associated with Big Data discourse and methods.Economic and Social
Research CouncilES/F028180/1Leverhulme TrustRPG-2013-153European Union’s Seventh Framework Programme (FP7/2007-2013ERC grant
agreement number 335925
The materiality of digital media: The hard disk drive, phonograph, magnetic tape and optical media in technical close-up
Popular discourses surrounding contemporary digital media often misrepresent it as immaterial and ephemeral, overlooking the material devices that store and generate our media objects. This article materially ‘descends’ into a selection of prior media forms that make up the genealogy of the hard disk drive (HDD) to challenge our reliance on conceptual misrepresentations. This material analysis is used to situate digital media in a genealogy of prior media forms, to enrich our understanding of how media’s affordances arise from the interplay of both formal and forensic materiality and to demonstrate the value of reintegrating materiality back into the study of media
Mimicry and well known genetic friends: molecular diagnosis in an Iranian cohort of suspected Bartter syndrome and proposition of an algorithm for clinical differential diagnosis.
BACKGROUND: Bartter Syndrome is a rare, genetically heterogeneous, mainly autosomal recessively inherited condition characterized by hypochloremic hypokalemic metabolic alkalosis. Mutations in several genes encoding for ion channels localizing to the renal tubules including SLC12A1, KCNJ1, BSND, CLCNKA, CLCNKB, MAGED2 and CASR have been identified as underlying molecular cause. No genetically defined cases have been described in the Iranian population to date. Like for other rare genetic disorders, implementation of Next Generation Sequencing (NGS) technologies has greatly facilitated genetic diagnostics and counseling over the last years. In this study, we describe the clinical, biochemical and genetic characteristics of patients from 15 Iranian families with a clinical diagnosis of Bartter Syndrome. RESULTS: Age range of patients included in this study was 3 months to 6 years and all patients showed hypokalemic metabolic alkalosis. 3 patients additionally displayed hypercalciuria, with evidence of nephrocalcinosis in one case. Screening by Whole Exome Sequencing (WES) and long range PCR revealed that 12/17 patients (70%) had a deletion of the entire CLCNKB gene that was previously identified as the most common cause of Bartter Syndrome in other populations. 4/17 individuals (approximately 25% of cases) were found to suffer in fact from pseudo-Bartter syndrome resulting from congenital chloride diarrhea due to a novel homozygous mutation in the SLC26A3 gene, Pendred syndrome due to a known homozygous mutation in SLC26A4, Cystic Fibrosis (CF) due to a novel mutation in CFTR and apparent mineralocorticoid excess syndrome due to a novel homozygous loss of function mutation in HSD11B2 gene. 1 case (5%) remained unsolved. CONCLUSIONS: Our findings demonstrate deletion of CLCNKB is the most common cause of Bartter syndrome in Iranian patients and we show that age of onset of clinical symptoms as well as clinical features amongst those patients are variable. Further, using WES we were able to prove that nearly 1/4 patients in fact suffered from Pseudo-Bartter Syndrome, reversing the initial clinical diagnosis with important impact on the subsequent treatment and clinical follow up pathway. Finally, we propose an algorithm for clinical differential diagnosis of Bartter Syndrome
Targeting effector memory T cells with alefacept in new onset type 1 diabetes: 12 month results from the T1DAL study
Background Type 1 diabetes (T1D) results from autoimmune targeting of the pancreatic beta cells, likely mediated by effector memory T cells (Tems). CD2, a T cell surface protein highly expressed on Tems, is targeted by the fusion protein alefacept, depleting Tems and central memory T cells (Tcms). We hypothesized that alefacept would arrest autoimmunity and preserve residual beta cells in newly diagnosed T1D. Methods The T1DAL study is a phase II, double-blind, placebo-controlled trial that randomised T1D patients 12-35 years old within 100 days of diagnosis, 33 to alefacept (two 12-week courses of 15 mg IM per week, separated by a 12-week pause) and 16 to placebo, at 14 US sites. The primary endpoint was the change from baseline in mean 2-hour C-peptide area under the curve (AUC) at 12 months. This trial is registered with ClinicalTrials.gov, number NCT00965458. Findings The mean 2-hour C-peptide AUC at 12 months increased by 0.015 nmol/L (95% CI -0.080 to 0.110 nmol/L) in the alefacept group and decreased by 0.115 nmol/L (95% CI -0.278 to 0.047) in the placebo group, which was not significant (p=0.065). However, key secondary endpoints were met: the mean 4-hour C-peptide AUC was significantly higher (p=0.019), and daily insulin use and the rate of hypoglycemic events were significantly lower (p=0.02 and p<0.001, respectively) at 12 months in the alefacept vs. placebo groups. Safety and tolerability were comparable between groups. There was targeted depletion of Tems and Tcms, with sparing of naïve and regulatory T cells (Tregs). Interpretation At 12 months, alefacept preserved the 4-hour C-peptide AUC, lowered insulin use, and reduced hypoglycemic events, suggesting a signal of efficacy. Depletion of memory T cells with sparing of Tregs may be a useful strategy to preserve beta cell function in new-onset T1D
Two spatiotemporally distinct value systems shape reward-based learning in the human brain
Avoiding repeated mistakes and learning to reinforce rewarding decisions is critical for human survival and adaptive actions. Yet, the neural underpinnings of the value systems that encode different decision-outcomes remain elusive. Here coupling single-trial electroencephalography with simultaneously acquired functional magnetic resonance imaging, we uncover the spatiotemporal dynamics of two separate but interacting value systems encoding decision-outcomes. Consistent with a role in regulating alertness and switching behaviours, an early system is activated only by negative outcomes and engages arousal-related and motor-preparatory brain structures. Consistent with a role in reward-based learning, a later system differentially suppresses or activates regions of the human reward network in response to negative and positive outcomes, respectively. Following negative outcomes, the early system interacts and downregulates the late system, through a thalamic interaction with the ventral striatum. Critically, the strength of this coupling predicts participants’ switching behaviour and avoidance learning, directly implicating the thalamostriatal pathway in reward-based learning
Recommended from our members
Designing a Monitoring Program to Estimate Estuarine Survival of Anadromous Salmon Smolts: Simulating the Effect of Sample Design on Inference
A number of researchers have attempted to estimate salmonid smolt survival during outmigration through an estuary. However, it is currently unclear how the design of such studies influences the accuracy and precision of survival estimates. In this simulation study we consider four patterns of smolt survival probability in the estuary, and test the performance of several different sampling strategies for estimating estuarine survival assuming perfect detection. The four survival probability patterns each incorporate a systematic component (constant, linearly increasing, increasing and then decreasing, and two pulses) and a random component to reflect daily fluctuations in survival probability. Generally, spreading sampling effort (tagging) across the season resulted in more accurate estimates of survival. All sampling designs in this simulation tended to under-estimate the variation in the survival estimates because seasonal and daily variation in survival probability are not incorporated in the estimation procedure. This under-estimation results in poorer performance of estimates from larger samples. Thus, tagging more fish may not result in better estimates of survival if important components of variation are not accounted for. The results of our simulation incorporate survival probabilities and run distribution data from previous studies to help illustrate the tradeoffs among sampling strategies in terms of the number of tags needed and distribution of tagging effort. This information will assist researchers in developing improved monitoring programs and encourage discussion regarding issues that should be addressed prior to implementation of any telemetry-based monitoring plan. We believe implementation of an effective estuary survival monitoring program will strengthen the robustness of life cycle models used in recovery plans by providing missing data on where and how much mortality occurs in the riverine and estuarine portions of smolt migration. These data could result in better informed management decisions and assist in guidance for more effective estuarine restoration projects
Validation of the lupus nephritis clinical indices in childhood-onset systemic lupus erythematosus
OBJECTIVE: To validate clinical indices of lupus nephritis (LN) activity and damage when used in children against the criterion standard of kidney biopsy findings. METHODS: In 83 children requiring kidney biopsy the SLE Disease Activity Index Renal Domain (SLEDAI-R); British Isles Lupus Assessment Group index Renal Domain (BILAG-R), Systemic Lupus International Collaborating Clinics Renal Activity (SLICC-RAS) and Damage Index Renal Domain (SDI-R) were measured. Fixed effect and logistic models were done to predict International Society of Nephrology/Renal Pathology Society (ISN/RPS) class; low/moderate vs. high LN-activity [NIH Activity Index (NIH-AI) score:10; Tubulointerstitial Activity Index (TIAI) score:5) or the absence vs. presence of LN chronicity [NIH Chronicity Index (NIH-CI) score: 0 vs. \u3e/= 1]. RESULTS: There were 10, 50 and 23 patients with class I/II, III/IV and V, respectively. Scores of the clinical indices did not differentiate among patients by ISN/RPS class. The SLEDAI-R and SLICC-RAS but not the BILAG-R differed with LN-activity status defined by NIH-AI scores, while only the SLEDAI-R scores differed between LN-activity status based on TIAI scores. The sensitivity and specificity of the SDI-R to capture LN chronicity was 23.5% and 91.7%, respectively. Despite designed to measure LN-activity, SLICC-RAS and SLEDAI-R scores significantly differed with LN chronicity status. CONCLUSION: Current clinical indices of LN fail to discriminate ISN/RPS Class in children. Despite its shortcomings, the SLEDAI-R appears to best for measuring LN activity in a clinical setting. The SDI-R is a poor correlate of LN chronicity. This article is protected by copyright. All rights reserved
Development of a novel renal activity index of lupus nephritis in children & young adults
BACKGROUND: Noninvasive estimation of the degree of inflammation seen on kidney biopsy with lupus nephritis (LN) remains difficult. The objective of this study was to develop a Renal Activity Index for Lupus (RAIL) that, based solely on laboratory measures, accurately reflects histological LN activity. METHODS: We assayed traditional LN laboratory tests and 16 urine biomarkers (UBMs) in children (n=47) at the time of kidney biopsy. Histological LN activity was measured by the NIH Activity Index (NIH-AI) and the Tubulointerstitial Activity Index (TIAI). High LN-activity status (vs. moderate/low) was defined as NIH-AI scores \u3e 10 (vs.5 (vs.92% accuracy and LN-activityTIAI status with \u3e80% accuracy. RAIL accuracy was minimally influenced by concomitant LN damage. Accuracies between 71 and 85% were achieved without standardization of the UBMs. The strength of these UBMs to reflect LN-activity status was confirmed by principal component and linear discriminant analyses. CONCLUSION: The RAIL is a robust and highly accurate noninvasive measure of LN-activity. The measurement properties of the RAIL, which reflect the degree of inflammatory changes as seen on kidney biopsy, will require independent validation. This article is protected by copyright. All rights reserved
Visual attention and action: How cueing, direct mapping, and social interactions drive orienting
Despite considerable interest in both action perception and social attention over the last 2 decades, there has been surprisingly little investigation concerning how the manual actions of other humans orient visual attention. The present review draws together studies that have measured the orienting of attention, following observation of another’s goal-directed action. Our review proposes that, in line with the literature on eye gaze, action is a particularly strong orienting cue for the visual system. However, we additionally suggest that action may orient visual attention using mechanisms, which gaze direction does not (i.e., neural direct mapping and corepresentation). Finally, we review the implications of these gaze-independent mechanisms for the study of attention to action. We suggest that our understanding of attention to action may benefit from being studied in the context of joint action paradigms, where the role of higher level action goals and social factors can be investigated
Pilot study comparing the childhood arthritis and rheumatology research alliance consensus treatment plans for induction therapy of juvenile proliferative lupus nephritis
BACKGROUND: To reduce treatment variability and facilitate comparative effectiveness studies, the Childhood Arthritis and Rheumatology Research Alliance (CARRA) published consensus treatment plans (CTPs) including one for juvenile proliferative lupus nephritis (LN). Induction immunosuppression CTPs outline treatment with either monthly intravenous (IV) cyclophosphamide (CYC) or mycophenolate mofetil (MMF) in conjunction with one of three corticosteroid (steroid) CTPs: primarily oral, primarily IV or mixed oral/IV. The acceptability and in-practice use of these CTPs are unknown. Therefore, the primary aims of the pilot study were to demonstrate feasibility of adhering to the LN CTPs and delineate barriers to implementation in clinical care in the US. Further, we aimed to explore the safety and effectiveness of the treatments for induction therapy.METHODS: Forty-one patients were enrolled from 10 CARRA sites. Patients had new-onset biopsy proven ISN/RPS class III or IV proliferative LN, were starting induction therapy with MMF or IV CYC and high-dose steroids and were followed for up to 24 months. Routine clinical data were collected at each visit. Provider reasons for CTP selection were assessed at baseline. Adherence to the CTPs was evaluated by provider survey and medication logs. Complete and partial renal responses were reported at 6 months.RESULTS: The majority of patients were female (83%) with a mean age of 14.7 years, SD 2.8. CYC was used more commonly than MMF for patients with ISN/RPS class IV LN (vs. class III), those who had hematuria, and those with adherence concerns. Overall adherence to the immunosuppression induction CTPs was acceptable with a majority of patients receiving the target MMF (86%) or CYC (63%) dose. However, adherence to the steroid CTPs was poor (37%) with large variability in dosing. Renal response endpoints were exploratory and did not show a significant difference between CYC and MMF.CONCLUSIONS: Overall, the immunosuppression CTPs were followed as intended in the majority of patients however, adherence to the steroid CTPs was poor indicating revision is necessary. In addition, our pilot study revealed several sources of treatment selection bias that will need to be addressed in for future comparative effectiveness research
- …
