31 research outputs found
Working knowledge, uncertainty and ontological politics: An ethnography of UK long covid clinics
Long covid (persistent COVIDâ19) is a new disease with contested aetiology and variable prognosis. We report a 2âyear ethnography of UK long covid clinics. Using a preformative lens, we show that multidisciplinary teams (MDTs) built working knowledge based on shared practices, mutual trust, distributed cognition (e.g. emails, record entries), relational knowledge of what was at stake for the patient, and harnessing uncertainty to open new discursive spaces. Most long covid MDTs performed the working knowledge of ârehabilitationâ, a linked set of practices oriented to ensuring that the patient understood and strove to âcorrectâ maladaptive physiological responses (e.g. through breathing exercises) and pursued recovery goals, supported by physiotherapists, psychologists and generalist clinicians. Some MDTs with a higher proportion of doctors (e.g. cardiologists, neurologists, immunologists) enacted the working knowledge of âmicroscopic damageâ, seeking to elucidate and rectify long covidâs underlying molecular and cellular pathology. They justified nonâstandard investigations and medication in selected patients by coâconstructing an evidentiary narrative based on biological mechanisms. Working knowledge was ontologically concordant within MDTs but sometimes discordant between MDTs. Overt ontological conflict occurred mostly when patients attending ârehabilitationâ clinics invoked the working knowledge of microscopic damage that had been generated and circulated in online support communities
Dual positive and negative regulation of GPCR signaling by GTP hydrolysis
G protein-coupled receptors (GPCRs) regulate a variety of intracellular pathways through their ability to promote the binding of GTP to heterotrimeric G proteins. Regulator of G protein signaling (RGS) proteins increase the intrinsic GTPase activity of G-subunits and are widely regarded as
negative regulators of G protein signaling. Using yeast we demonstrate that GTP hydrolysis is not only required for desensitization, but is essential for achieving a high maximal (saturated level) response. Thus RGS-mediated GTP hydrolysis acts as both a negative (low stimulation) and
positive (high stimulation) regulator of signaling. To account for this we generated a new kinetic model of the G protein cycle where GGTP enters an inactive GTP-bound state following effector activation. Furthermore, in vivo and in silico experimentation demonstrates that maximum signaling output first increases and then decreases with RGS concentration. This unimodal, non-monotone
dependence on RGS concentration is novel. Analysis of the kinetic model has revealed a dynamic network motif that shows precisely how inclusion of the inactive GTP-bound state for the G produces this unimodal relationship
CSF tau and the CSF tau/ABeta ratio for the diagnosis of Alzheimer's disease dementia and other dementias in people with mild cognitive impairment (MCI).
BACKGROUND: Research suggests that measurable change in cerebrospinal fluid (CSF) biomarkers occurs years in advance of the onset of clinical symptoms (Beckett 2010). In this review, we aimed to assess the ability of CSF tau biomarkers (t-tau and p-tau) and the CSF tau (t-tau or p-tau)/ABeta ratio to enable the detection of Alzheimer's disease pathology in patients with mild cognitive impairment (MCI). These biomarkers have been proposed as important in new criteria for Alzheimer's disease dementia that incorporate biomarker abnormalities. OBJECTIVES: To determine the diagnostic accuracy of 1) CSF t-tau, 2) CSF p-tau, 3) the CSF t-tau/ABeta ratio and 4) the CSF p-tau/ABeta ratio index tests for detecting people with MCI at baseline who would clinically convert to Alzheimer's disease dementia or other forms of dementia at follow-up. SEARCH METHODS: The most recent search for this review was performed in January 2013. We searched MEDLINE (OvidSP), Embase (OvidSP), BIOSIS Previews (Thomson Reuters Web of Science), Web of Science Core Collection, including Conference Proceedings Citation Index (Thomson Reuters Web of Science), PsycINFO (OvidSP), and LILACS (BIREME). We searched specialized sources of diagnostic test accuracy studies and reviews. We checked reference lists of relevant studies and reviews for additional studies. We contacted researchers for possible relevant but unpublished data. We did not apply any language or data restriction to the electronic searches. We did not use any methodological filters as a method to restrict the search overall. SELECTION CRITERIA: We selected those studies that had prospectively well-defined cohorts with any accepted definition of MCI and with CSF t-tau or p-tau and CSF tau (t-tau or p-tau)/ABeta ratio values, documented at or around the time the MCI diagnosis was made. We also included studies which looked at data from those cohorts retrospectively, and which contained sufficient data to construct two by two tables expressing those biomarker results by disease status. Moreover, studies were only selected if they applied a reference standard for Alzheimer's disease dementia diagnosis, for example, the NINCDS-ADRDA or Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. DATA COLLECTION AND ANALYSIS: We screened all titles generated by the electronic database searches. Two review authors independently assessed the abstracts of all potentially relevant studies, and the full papers for eligibility. Two independent assessors performed data extraction and quality assessment. Where data allowed, we derived estimates of sensitivity at fixed values of specificity from the model we fitted to produce the summary receiver operating characteristic (ROC) curve. MAIN RESULTS: In total, 1282 participants with MCI at baseline were identified in the 15 included studies of which 1172 had analysable data; 430 participants converted to Alzheimer's disease dementia and 130 participants to other forms of dementia. Follow-up ranged from less than one year to over four years for some participants, but in the majority of studies was in the range one to three years. Conversion to Alzheimer's disease dementia The accuracy of the CSF t-tau was evaluated in seven studies (291 cases and 418 non-cases).The sensitivity values ranged from 51% to 90% while the specificity values ranged from 48% to 88%. At the median specificity of 72%, the estimated sensitivity was 75% (95% CI 67 to 85), the positive likelihood ratio was 2.72 (95% CI 2.43 to 3.04), and the negative likelihood ratio was 0.32 (95% CI 0.22 to 0.47).Six studies (164 cases and 328 non-cases) evaluated the accuracy of the CSF p-tau. The sensitivities were between 40% and 100% while the specificities were between 22% and 86%. At the median specificity of 47.5%, the estimated sensitivity was 81% (95% CI: 64 to 91), the positive likelihood ratio was 1.55 (CI 1.31 to 1.84), and the negative likelihood ratio was 0.39 (CI: 0.19 to 0.82).Five studies (140 cases and 293 non-cases) evaluated the accuracy of the CSF p-tau/ABeta ratio. The sensitivities were between 80% and 96% while the specificities were between 33% and 95%. We did not conduct a meta-analysis because the studies were few and small. Only one study reported the accuracy of CSF t-tau/ABeta ratio.Our findings are based on studies with poor reporting. A significant number of studies had unclear risk of bias for the reference standard, participant selection and flow and timing domains. According to the assessment of index test domain, eight of 15 studies were of poor methodological quality.The accuracy of these CSF biomarkers for 'other dementias' had not been investigated in the included primary studies. Investigation of heterogeneity The main sources of heterogeneity were thought likely to be reference standards used for the target disorders, sources of recruitment, participant sampling, index test methodology and aspects of study quality (particularly, inadequate blinding).We were not able to formally assess the effect of each potential source of heterogeneity as planned, due to the small number of studies available to be included. AUTHORS' CONCLUSIONS: The insufficiency and heterogeneity of research to date primarily leads to a state of uncertainty regarding the value of CSF testing of t-tau, p-tau or p-tau/ABeta ratio for the diagnosis of Alzheimer's disease in current clinical practice. Particular attention should be paid to the risk of misdiagnosis and overdiagnosis of dementia (and therefore over-treatment) in clinical practice. These tests, like other biomarker tests which have been subject to Cochrane DTA reviews, appear to have better sensitivity than specificity and therefore might have greater utility in ruling out Alzheimer's disease as the aetiology to the individual's evident cognitive impairment, as opposed to ruling it in. The heterogeneity observed in the few studies awaiting classification suggests our initial summary will remain valid. However, these tests may have limited clinical value until uncertainties have been addressed. Future studies with more uniformed approaches to thresholds, analysis and study conduct may provide a more homogenous estimate than the one that has been available from the included studies we have identified
The role of the RACK1 ortholog Cpc2p in modulating pheromone-induced cell cycle arrest in fission yeast
The detection and amplification of extracellular signals requires the involvement of multiple protein components. In mammalian cells the receptor of activated C kinase (RACK1) is an important scaffolding protein for signal transduction networks. Further, it also performs a critical function in regulating the cell cycle by modulating the G1/S transition. Many eukaryotic cells express RACK1 orthologs, with one example being Cpc2p in the fission yeast Schizosaccharomyces pombe. In contrast to RACK1, Cpc2p has been described to positively regulate, at the ribosomal level, cells entry into M phase. In addition, Cpc2p controls the stress response pathways through an interaction with Msa2p, and sexual development by modulating Ran1p/Pat1p. Here we describe investigations into the role, which Cpc2p performs in controlling the G protein-mediated mating response pathway. Despite structural similarity to GÎČ-like subunits, Cpc2p appears not to function at the G protein level. However, upon pheromone stimulation, cells overexpressing Cpc2p display substantial cell morphology defects, disorientation of septum formation and a significantly protracted G1 arrest. Cpc2p has the potential to function at multiple positions within the pheromone response pathway. We provide a mechanistic interpretation of this novel data by linking Cpc2p function, during the mating response, with its previous described interactions with Ran1p/Pat1p. We suggest that overexpressing Cpc2p prolongs the stimulated state of pheromone-induced cells by increasing ste11 gene expression. These data indicate that Cpc2p regulates the pheromone-induced cell cycle arrest in fission yeast by delaying cells entry into S phase
Safety implications of remote assessments for suspected COVID-19: qualitative study in UK primary care
Background:Â The introduction of remote triage and assessment early in the pandemic raised questions about patient safety. We sought to capture patients and cliniciansâ experiences of the management of suspected acute COVID-19 and generate wider lessons to inform safer care.
Setting and sample:Â UK primary healthcare. A subset of relevant data was drawn from five linked in-pandemic qualitative studies. The data set, on a total of 87 participants recruited via social media, patient groups and snowballing, comprised free text excerpts from narrative interviews (10 survivors of acute COVID-19), online focus groups (20 patients and 30 clinicians), contributions to a Delphi panel (12 clinicians) and fieldnotes from an online workshop (15 patients, clinicians and stakeholders).
Methods:Â Data were uploaded onto NVivo. Coding was initially deductive and informed by WHO and Institute of Medicine frameworks of quality and safety. Further inductive analysis refined our theorisation using a wider range of theoriesâincluding those of risk, resilience, crisis management and social justice.
Results:Â In the early weeks of the pandemic, patient safety was compromised by the driving logic of âstay homeâ and âprotect the NHSâ, in which both patients and clinicians were encouraged to act in a way that helped reduce pressure on an overloaded system facing a novel pathogen with insufficient staff, tools, processes and systems. Furthermore, patients and clinicians observed a shift to a more transactional approach characterised by overuse of algorithms and decision support tools, limited empathy and lack of holistic assessment.
Conclusion:Â Lessons from the pandemic suggest three key strategies are needed to prevent avoidable deaths and inequalities in the next crisis: (1) strengthen system resilience (including improved resourcing and staffing; support of new tools and processes; and recognising primary careâs role as the ârisk sinkâ of the healthcare system); (2) develop evidence-based triage and scoring systems; and (3) address social vulnerability
Training needs for staff providing remote services in general practice: a mixed-methods study
Background Contemporary general practice includes many kinds of remote encounter. The rise in telephone, video and online modalities for triage and clinical care requires clinicians and support staff to be trained, both individually and as teams, but evidence-based competencies have not previously been produced for general practice.
Aim To identify training needs, core competencies, and learning methods for staff providing remote encounters.
Design and setting Mixed-methods study in UK general practice.
Method Data were collated from longitudinal ethnographic case studies of 12 general practices; a multi-stakeholder workshop; interviews with policymakers, training providers, and trainees; published research; and grey literature (such as training materials and surveys). Data were coded thematically and analysed using theories of individual and team learning.
Results Learning to provide remote services occurred in the context of high workload, understaffing, and complex workflows. Low confidence and perceived unmet training needs were common. Training priorities for novice clinicians included basic technological skills, triage, ethics (for privacy and consent), and communication and clinical skills. Established cliniciansâ training priorities include advanced communication skills (for example, maintaining rapport and attentiveness), working within the limits of technologies, making complex judgements, coordinating multi-professional care in a distributed environment, and training others. Much existing training is didactic and technology focused. While basic knowledge was often gained using such methods, the ability and confidence to make complex judgements were usually acquired through experience, informal discussions, and on-the-job methods such as shadowing. Whole-team training was valued but rarely available. A draft set of competencies is offered based on the findings.
Conclusion The knowledge needed to deliver high-quality remote encounters to diverse patient groups is complex, collective, and organisationally embedded. The vital role of non-didactic training, for example, joint clinical sessions, case-based discussions, and in-person, whole-team, on-the-job training, needs to be recognised
Remote care in UK general practice: baseline data on 11 case studies [version 2; peer review: 2 approved]
Background: Accessing and receiving care remotely (by telephone, video or online) became the default option during the coronavirus disease 2019 (COVID-19) pandemic, but in-person care has unique benefits in some circumstances. We are studying UK general practices as they try to balance remote and in-person care, with recurrent waves of COVID-19 and various post-pandemic backlogs. Methods: Mixed-methods (mostly qualitative) case study across 11 general practices. Researchers-in-residence have built relationships with practices and become familiar with their contexts and activities; they are following their progress for two years via staff and patient interviews, documents and ethnography, and supporting improvement efforts through co-design. In this paper, we report baseline data. Results: Reflecting our maximum-variety sampling strategy, the 11 practices vary in size, setting, ethos, staffing, population demographics and digital maturity, but share common contextual featuresânotably system-level stressors such as high workload and staff shortages, and UKâs technical and regulatory infrastructure. We have identified both commonalities and differences between practices in terms of how they: 1] manage the âdigital front doorâ (access and triage) and balance demand and capacity; 2] strive for high standards of quality and safety; 3] ensure digital inclusion and mitigate wider inequalities; 4] support and train their staff (clinical and non-clinical), students and trainees; 5] select, install, pilot and use technologies and the digital infrastructure which support them; and 6] involve patients in their improvement efforts. Conclusions: General practicesâ responses to pandemic-induced disruptive innovation appear unique and situated. We anticipate that by focusing on depth and detail, this longitudinal study will throw light on why a solution that works well in one practice does not work at all in another. As the study unfolds, we will explore how practices achieve timely diagnosis of urgent or serious illness and manage continuity of care, long-term conditions and complex needs
Protocol: Remote care as the ânew normalâ? Multi-site case study in UK general practice [version 1; peer review: 2 approved]
Background:Â Following a pandemic-driven shift to remote service provision, UK general practices offer telephone, video or online consultation options alongside face-to-face. This study explores practicesâ varied experiences over time as they seek to establish remote forms of accessing and delivering care. Methods:Â This protocol is for a mixed-methods multi-site case study with co-design and national stakeholder engagement. 11 general practices were selected for diversity in geographical location, size, demographics, ethos, and digital maturity. Each practice has a researcher-in-residence whose role is to become familiar with its context and activity, follow it longitudinally for two years using interviews, public-domain documents and ethnography, and support improvement efforts. Research team members meet regularly to compare and contrast across cases. Practice staff are invited to join online learning events. Patient representatives work locally within their practice patient involvement groups as well as joining an online patient learning set or linking via a non-digital buddy system. NHS Research Ethics Approval has been granted. Governance includes a diverse independent advisory group with lay chair. We also have policy in-reach (national stakeholders sit on our advisory group) and outreach (research team members sit on national policy working groups). Results (anticipated): We expect to produce rich narratives of contingent change over time, addressing cross-cutting themes including access, triage and capacity; digital and wider inequities; quality and safety of care (e.g. continuity, long-term condition management, timely diagnosis, complex needs); workforce and staff wellbeing (including non-clinical staff, students and trainees); technologies and digital infrastructure; patient perspectives; and sustainability (e.g. carbon footprint). Conclusion:Â By using case study methods focusing on depth and detail, we hope to explain why digital solutions that work well in one practice do not work at all in another. We plan to inform policy and service development through inter-sectoral network-building, stakeholder workshops and topic-focused policy briefings
A DHODH inhibitor increases p53 synthesis and enhances tumor cell killing by p53 degradation blockage
ML, CD, IvL, GP, TM, SD, MS, APF, CT, DL, MAH, KL and SL: project grants from the Swedish Research Council, the Swedish Cancer Society and the Swedish Childhood Cancer Foundation. MHi and JC: Cancer Research UK (C8/A6613). MC, EP and WE: Wellcome Trust (073915). MN and BV: projects MEYS-NPS-LO1413 and GACR P206/12/G151. EMC, MP, MMS, ZF and PG: Norwegian Cancer Society (182735, 732200) and Helse Vest (911884, 911789). RB and SC: NIH (R01 CA95684), the Leukemia and Lymphoma Society and the Waxman Foundation. NW, AH, AdâH: Cancer Research UK (C21383/A6950) and Engineering and Physical Sciences Research Council Doctoral Training Program. JL and YZ: Cancer Research UK (C240/A15751). MH and BW: SARomics Biostructures ABUY, KF: DDDP SciLife, Sweden. LJ, MHa, RS and A-LG: CBCS, Sweden. VP: SciLife fellowship. AT: Breast Cancer Research Scotland.The development of non-genotoxic therapies that activate wild-type p53 in tumors is of great interest since the discovery of p53 as a tumor suppressor. Here we report the identification of over 100 small-molecules activating p53 in cells. We elucidate the mechanism of action of a chiral tetrahydroindazole (HZ00), and through target deconvolution, we deduce that its active enantiomer (R)-HZ00, inhibits dihydroorotate dehydrogenase (DHODH). The chiral specificity of HZ05, a more potent analog, is revealed by the crystal structure of the (R)-HZ05/DHODH complex. Twelve other DHODH inhibitor chemotypes are detailed among the p53 activators, which identifies DHODH as a frequent target for structurally diverse compounds. We observe that HZ compounds accumulate cancer cells in S-phase, increase p53 synthesis, and synergize with an inhibitor of p53 degradation to reduce tumor growth in vivo. We, therefore, propose a strategy to promote cancer cell killing by p53 instead of its reversible cell cycle arresting effect.Publisher PDFPeer reviewe