In vitro modulation of inflammatory cytokine and IgG levels by extracts of Perna canaliculus

BACKGROUND: Inflammation is a predominant characteristic of autoimmune diseases which is characterized by the increased expression of pro-inflammatory cytokines. Soon to be published work from our laboratory has shown that ingestion of Perna canaliculus prevents the development of autoimmune diseases such as Systemic Lupus Erythematosus and rheumatoid arthritis in laboratory animals. The current paper attempts to illustrate how Perna can alleviate inflammation by modulating inflammatory cytokines, cyclooxygenase enzymes and Immunoglobulin-G (IgG) levels. METHODS: In the present study, hydrochloric acid [HCl] and Tween-20 were used to develop extracts of Perna. These extracts were assayed for protein content. Increasing concentrations of these extracts were then tested in cell culture for modulation of inflammatory cytokine, cyclooxygenase enzymes and IgG levels. Parallel tests were run using an available glycogen extract of Perna as a comparison to our in-house laboratory preparations. RESULTS: Tween-20 Perna extracts were found to be more stable and less toxic in cell culture than HCl digest of Perna. They also assayed higher in protein content that HCl extracts. Although both extracts inhibited IgG production in V2E9 hybridomas, Tween-20 extracts were more consistent in IgG suppression than HCl extracts. Overall Tween-20 extracts effectively decreased levels of TNF-α, IL-1, IL-2 and IL-6 as observed using cytokine bioassays. Twenty micrograms of Tween-20 Perna extracts induced such significant decreases in inflammatory cytokine production that when tested on sensitive cell lines, they very nearly abolished the decrease in viability induced by these cytokines. Tween-20 extracts effectively inhibited both COX-1 and COX-2 cyclooxygenase activity. As a comparison, the glycogen extract also demonstrated a similar though weaker effect on COX-1 and COX-2 enzymes. The active components of both extracts (Tween-20 and glycogen) were observed to possess molecular weights above 100 kDa. Although the anti-cytokine activity of the Tween-20 extract was destroyed by Proteinase-K treatment, the anti-COX-1 and anti-COX-2 activity of both the extracts were not sensitive to protease treatment. CONCLUSION: We have successfully demonstrated modulation in the levels of inflammatory cytokines, cyclooxygenase enzymes and immunoglobulins by our in-house laboratory preparations of Perna canaliculus, whereby suggesting an immunomodulatory role of Perna canaliculus in regulating inflammation

How do cardiologists select patients for dual antiplatelet therapy continuation beyond 1 year after a myocardial infarction? Insights from the EYESHOT Post-MI Study

Background: Current guidelines suggest to consider dual antiplatelet therapy (DAPT) continuation for longer than 12 months in selected patients with myocardial infarction (MI). Hypothesis: We sought to assess the criteria used by cardiologists in daily practice to select patients with a history of MI eligible for DAPT continuation beyond 1 year. Methods: We analyzed data from the EYESHOT Post-MI, a prospective, observational, nationwide study aimed to evaluate the management of patients presenting to cardiologists 1 to 3 years from the last MI event. Results: Out of the 1633 post-MI patients enrolled in the study between March and December 2017, 557 (34.1%) were on DAPT at the time of enrolment, and 450 (27.6%) were prescribed DAPT after cardiologist assessment. At multivariate analyses, a percutaneous coronary intervention (PCI) with multiple stents and the presence of peripheral artery disease (PAD) resulted as independent predictors of DAPT continuation, while atrial fibrillation was the only independent predictor of DAPT interruption for patients both at the second and the third year from MI at enrolment and the time of discharge/end of the visit. Conclusions: Risk scores recommended by current guidelines for guiding decisions on DAPT duration are underused and misused in clinical practice. A PCI with multiple stents and a history of PAD resulted as the clinical variables more frequently associated with DAPT continuation beyond 1 year from the index MI

Second asymptomatic carotid surgery trial (ACST-2): a randomised comparison of carotid artery stenting versus carotid endarterectomy

Background: Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods: ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings: Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86–1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA trials, the RR was similar in symptomatic and asymptomatic patients (overall RR 1·11, 95% CI 0·91–1·32; p=0·21). Interpretation: Serious complications are similarly uncommon after competent CAS and CEA, and the long-term effects of these two carotid artery procedures on fatal or disabling stroke are comparable. Funding: UK Medical Research Council and Health Technology Assessment Programme

Identification of a 24-kDa cytokine that is required for development of cytolytic T lymphocytes.

It is known that the production of cytolytic T lymphocytes requires growth factors such as interleukins 2 and 4 (IL-2 and IL-4). Elsewhere we have described bioassays that detect a cytokine that operates in concert with growth factor to generate cytolytic T lymphocytes. The factor that is termed cytolytic T-lymphocyte differentiation factor (CDF), together with IL-2 and lectin, mediates the formation of CD8+ killer cells in 2 days from thymocyte or peripheral lymphoid precursors. CDF is not mimicked by natural or recombinant sources of interferons, colony-stimulating factors, and IL-1 to IL-4. Here we use these bioassays to isolate and further characterize a single 24-kDa CDF protein from the conditioned medium of stimulated human blood mononuclear cells. CDF is first enriched by three successive chromatographic procedures that utilize anion exchange, hydroxyapatite, and phenyl-Superose. A single 24-kDa band with CDF activity is then isolated on 12% NaDodSO4/PAGE and clearly distinguished from the 17-kDa band of IL-2. The apparent molecular mass is similar under reducing and nonreducing conditions. After elution from NaDodSO4/PAGE the cytokine is maximally active at 0.25 nM in the CDF assay and has no growth factor activity for T lymphoblasts. To generate cytolytic CD8+, CD4- cells from spleen and lymph node T lymphocytes, IL-2 and small numbers of accessory dendritic cells must be applied together with CDF

Measurement of beryllium isotopic composition in cosmic rays with the AMS-02 experiment on the International Space Station

Cosmic rays are a powerful tool for the investigation of the structure of the magnetic fields in the galactic halo and of the properties of the Inter-Stellar Medium. Two parameters of the cosmic rays propagation models, the galactic halo (half-) thickness, H, and the diffusion coefficient, D, are loosely constrained by current cosmic rays flux measurements, in particular a large degeneracy exists being only H/D well measured. The 10Be/9Be isotopic flux ratio (thanks to the 2 My lifetime of 10Be) can be used as a radioactive clock providing the measurement of cosmic rays residence time in the galaxy. This is an important probe to solve the H/D degeneracy. Past measurements of 10Be/9Be isotopic flux ratio in CR are scarce, limited to low energy and affected by large uncertainties. In this work, new preliminary measurements of 10Be/9Be and complementary 7Be/Be flux ratios are presented, both obtained from the data of the AMS-02 experiment

ROLE OF INTERLEUKIN-6 IN THE GENERATION OF HUMAN CYTOLYTIC T-CELL CLONES

The maturation of cytolytic T lymphocytes from non-lytic precursors requires cytokines other than IL-2. Interleukin-6 is the principal cytokine that cooperates with IL-2 in the induction of CTL differentiation from murine and human thymocyte precursors. However, a cytotoxic differentiation factor role for IL-6 on mature T cells is challenged by data that indicate that IL-2 alone is sufficient for CTL generation. The aim of this study was to identify a model system in which IL-6 acted as a CDF for human peripheral T cells. Experiments that compared the cytolytic function of CTL clones cultured with and without IL-6 demonstrated that IL-6 contributes to the cytolytic activity of human CTL clones. We also demonstrate that IL-6 is endogenously produced by CTL clones in the course of their expansion with APC, lectin and IL-2. The majority of both CD4+ and CD8+ clones produced IL-6 in response to relatively high doses of IL-2. Our data suggest that IL-6 acts in an autocrine fashion to support CTL differentiation in human T-cell clones