Posttranslational processing of concanavalin A precursors in jackbean cotyledons

Metabolic labeling of immature jackbean cotyledons with 14C-amino acids was used to determine the processing steps involved in the assembly of concanavalin A. Pulse-chase experiments and analyses of immunoprecipitated lectin forms indicated a complex series of events involving seven distinct species. The structural relatedness of all of the intermediate species was confirmed by two-dimensional mapping of 125I-tryptic peptides. An initial glycosylated precursor was deglycosylated and cleaved into smaller polypeptides, which subsequently reannealed over a period of 10-27 h. NH2-terminal sequencing of the abundant precursors confirmed that the intact subunit of concanavalin A was formed by the reannealing of two fragments, since the alignment of residues 1-118 and 119-237 was reversed in the final form of the lectin identified in the chase and the precursor first labeled. When the tissue was pulse-chased in the presence of monensin, processing of the glycosylated precursor was inhibited. The weak bases NH4Cl and chloroquine were without effect. Immunocytochemical studies showed that monensin treatment caused the accumulation of immunoreactive material at the cell surface and indicated that the ionophore had induced the secretion of a component normally destined for deposition within the protein bodies. Consideration of the tertiary structure of the glycosylated precursor and mature lectin showed that the entire series of processing events could occur without significant refolding of the initial translational product. Proteolytic events included removal of a peptide from the surface of the precursor molecule that connected the NH2- and COOH-termini of the mature protein. This processing activated the carbohydrate-binding activity of the lectin. The chase data suggest the occurrence of a simultaneous cleavage and formation of a peptide bond, raising the possibility that annealment of the fragments to give rise to the mature subunit involves a transpeptidation event rather than cleavage and subsequent religation

Effect of Bruton's tyrosine kinase inhibitors on platelet aggregation in patients with acute myocardial infarction

Aims: Despite widespread use of dual antiplatelet therapy in acute myocardial infarction, there remains a residual risk of morbidity and mortality. Bruton's Tyrosine Kinase inhibitors have been found to inhibit platelet aggregation through the Glycoprotein VI collagen-mediated pathway. The Bruton's Tyrosine Kinase inhibitor, Ibrutinib is used in the management of haematological malignancies and another Bruton's Tyrosine Kinase inhibitor, ONO-4059 (also known as tirabrutinib), is in clinical development. This is an observational study to evaluate the effects of Ibrutinib and ONO-4059 on platelet aggregation after acute myocardial infarction. Methods and results: Twenty patients with a confirmed diagnosis of acute myocardial infarction were enrolled and blood samples obtained within 48 h of hospital admission. All patients were on dual antiplatelet therapy; aspirin plus a P2Y12 inhibitor (clopidogrel or ticagrelor). Blood samples were treated ex vivo with increasing concentrations of Ibrutinib (0, 0.5, 1, 2 μM) and ONO-4059 (0, 0.2, 0.5, 1 μM). Platelet aggregation was measured in response to collagen using a Multiplate analyser to estimate the area under the curve, with lower values indicating lower platelet aggregation. The median age was 63 years and 80% were male. The median area under the curve values for Ibrutinib concentrations 0 (control), 0.5, 1 and 2 mmol/l were 18.5, 8 (P = 0.0004), 4.5 (P < 0.0001) and 2 (P < 0.0001) units and for ONO-4059 concentrations 0 (control), 0.2, 0.5 and1μM, median area under the curve values were 13, 12 (P = 0.7), 6.5 (P = 0.0001) and 5.5 (P = 0.0004 compared to control). Conclusion: The Bruton's Tyrosine Kinase inhibitors, Ibrutinib and ONO-4059, show further inhibition of platelet aggregation in blood samples from patients with acute myocardial infarction, receiving dual antiplatelet therapy in a dose dependent manner. These results provide a rationale for Bruton's Tyrosine Kinase inhibitors to be tested as a potential new antiplatelet strategy for acute myocardial infarction

Inflammatory Differences in Plaque Erosion and Rupture in Patients With ST‐Segment Elevation Myocardial Infarction

Background: Plaque erosion causes 30% of ST‐segment elevation myocardial infarctions, but the underlying cause is unknown. Inflammatory infiltrates are less abundant in erosion compared with rupture in autopsy studies. We hypothesized that erosion and rupture are associated with significant differences in intracoronary cytokines in vivo. Methods and Results: Forty ST‐segment elevation myocardial infarction patients with <6 hours of chest pain were classified as ruptured fibrous cap (RFC) or intact fibrous cap (IFC) using optical coherence tomography. Plasma samples from the infarct‐related artery and a peripheral artery were analyzed for expression of 102 cytokines using arrays; results were confirmed with ELISA. Thrombectomy samples were analyzed for differential mRNA expression using quantitative real‐time polymerase chain reaction. Twenty‐three lesions were classified as RFC (58%), 15 as IFC (38%), and 2 were undefined (4%). In addition, 12% (12 of 102) of cytokines were differentially expressed in both coronary and peripheral plasma. I‐TAC was preferentially expressed in RFC (significance analysis of microarrays adjusted P<0.001; ELISA IFC 10.2 versus RFC 10.8 log2 pg/mL; P=0.042). IFC was associated with preferential expression of epidermal growth factor (significance analysis of microarrays adjusted P<0.001; ELISA IFC 7.42 versus RFC 6.63 log2 pg/mL, P=0.036) and thrombospondin 1 (significance analysis of microarrays adjusted P=0.03; ELISA IFC 10.4 versus RFC 8.65 log2 ng/mL, P=0.0041). Thrombectomy mRNA showed elevated I‐TAC in RFC (P=0.0007) epidermal growth factor expression in IFC (P=0.0264) but no differences in expression of thrombospondin 1. Conclusions: These results demonstrate differential intracoronary cytokine expression in RFC and IFC. Elevated thrombospondin 1 and epidermal growth factor may play an etiological role in erosion

The refinement paradox and cumulative cultural evolution : complex products of collective improvement favor conformist outcomes, blind copying, and hyper-credulity

Funding: Research supported in part by an European Research Council Advanced grant to KNL (EVOCULTURE, ref. 232823).Social learning is common in nature, yet cumulative culture (where knowledge and technology increase in complexity and diversity over time) appears restricted to humans. To understand why, we organized a computer tournament in which programmed entries specified when to learn new knowledge and when to refine (i.e. improve) existing knowledge. The tournament revealed a ‘refinement paradox’: refined behavior afforded higher payoffs as individuals converged on a small number of successful behavioral variants, but refining did not generally pay. Paradoxically, entries that refined only in certain conditions did best during behavioral improvement, while simple copying entries thrived when refinement levels were high. Cumulative cultural evolution may be rare in part because sophisticated strategies for improving knowledge and technology are initially advantageous, yet complex culture, once achieved, favors conformity, blind imitation and hyper-credulity.Peer reviewe

Determinants of Length of Stay Following Total Anterior Circulatory Stroke

Identification of factors that determine length of stay (LOS) in total anterior circulatory stroke (TACS) has potential for targeted intervention to reduce the associated health care burden. This study aimed to determine which factors predict LOS following either ischaemic or haemorrhagic TACS. The study sample population was drawn from the Norfolk and Norwich Stroke and Transient Ischemic Attack (TIA) Register (1996 – 2012), a prospective registry. 2965 patients admitted with TACS verified by a stroke specialist team were included. Primary analysis identified predictors of length of stay (LOS) in either haemorrhagic or ischaemic TACS. Secondary analyses identified predictors of LOS in patients who were discharged alive or who died during admission separately. Moderate (p=0.014) to severe disability (p=0.015) and history of congestive heart failure (p=0.027) in the primary analysis and pre-stroke residence in a care facility among patients who survived to discharge (p=0.013) were associated with a shorter length of stay. Factors associated with increased length of stay included presence of neurological lateralisation in the primary analysis (p=0.004) and amongst patients who died (p=0.003 and p=0.014 for ischaemic and haemorrhagic stroke, respectively). Patients with advanced age (≥85 years) with haemorrhagic stroke had longer LOS regardless of mortality outcome. Patients with low pre-morbid disability (modified Rankin score ≤2 who died following haemorrhagic TACS also had longer LOS. Our study found predictors of LOS following TACS include neurological lateralisation, pre-stroke disability status, congestive heart failure, pre-morbid residence and age. The identification of such factors would assist in resource allocation and discharge planning

Concert recording 2013-03-31b

[Track 01]. Sweet Georgie fame / Blossom Dearie -- [Track 02]. Joy spring / Clifford Brown -- [Track 03]. Summer samba / Marcos Valle -- [Track 04]. Rhythm\u27ning / Thelonious Monk -- [Track 05]. One note samba / Antonio Carlos Jobim -- [Track 06]. In a sentimental mood / Duke Ellington -- [Track 07]. Recordame / Joe Henderson -- [Track 08]. Full house / Wes Montgomery -- [Track 09]. Cats and kittens / Peter Erskine -- [Track 10]. Primal prayer / Dan Haerle -- [Track 11]. Cookin\u27 Boox / Detroit Jackson

SLACC: Simion-based Language Agnostic Code Clones

Successful cross-language clone detection could enable researchers and developers to create robust language migration tools, facilitate learning additional programming languages once one is mastered, and promote reuse of code snippets over a broader codebase. However, identifying cross-language clones presents special challenges to the clone detection problem. A lack of common underlying representation between arbitrary languages means detecting clones requires one of the following solutions: 1) a static analysis framework replicated across each targeted language with annotations matching language features across all languages, or 2) a dynamic analysis framework that detects clones based on runtime behavior. In this work, we demonstrate the feasibility of the latter solution, a dynamic analysis approach called SLACC for cross-language clone detection. Like prior clone detection techniques, we use input/output behavior to match clones, though we overcome limitations of prior work by amplifying the number of inputs and covering more data types; and as a result, achieve better clusters than prior attempts. Since clusters are generated based on input/output behavior, SLACC supports cross-language clone detection. As an added challenge, we target a static typed language, Java, and a dynamic typed language, Python. Compared to HitoshiIO, a recent clone detection tool for Java, SLACC retrieves 6 times as many clusters and has higher precision (86.7% vs. 30.7%). This is the first work to perform clone detection for dynamic typed languages (precision = 87.3%) and the first to perform clone detection across languages that lack a common underlying representation (precision = 94.1%). It provides a first step towards the larger goal of scalable language migration tools.Comment: 11 Pages, 3 Figures, Accepted at ICSE 2020 technical trac