76 research outputs found
Changes of Soluble CD40 Ligand in the Progression of Acute Myocardial Infarction Associate to Endothelial Nitric Oxide Synthase Polymorphisms and Vascular Endothelial Growth Factor But Not to Platelet CD62P Expression
Reported in vitro data implicated soluble CD40 ligand (sCD40L) in endothelial dysfunction and angiogenesis. However, whether sCD40L could exert that influence in endothelial dysfunction and angiogenesis after injury in acute myocardial infarction (AMI) patients remains unclear. In the present study, we evaluated the association of sCD40L with markers of platelet activation, endothelial, and vascular function during a recovery period early after AMI. To achieve this goal, the time changes of soluble, platelet-bound, and microparticle-bound CD40L levels over 1 month were assessed in AMI patients and correlated with endothelial nitric oxide synthase (eNOS) polymorphisms, vascular endothelial growth factor (VEGF) concentrations, and platelet expression of P-selectin (CD62P). The association of soluble form, platelet-bound, and microparticle-bound CD40L with CD62P expression on platelets, a marker of platelet activation, was also assessed to evaluate the role of CD40L in the thrombosis, whereas the association with eNOS and VEGF was to evaluate the role of CD40L in vascular dysfunction. This work shows for the first time that time changes of sCD40L over 1 month after myocardial infarct onset were associated with G894T eNOS polymorphism and with the VEGF concentrations, but not to the platelet CD62P expression. These results indicate that, in terms of AMI pathophysiology, the sCD40L cannot be consider just as being involved in thrombosis and inflammation but also as having a relevant role in vascular and endothelial dysfunction
Stratification of ST-Elevation Myocardial Infarction Patients Based on Soluble CD40L Longitudinal Changes
Involvement of soluble CD40 ligand (sCD40L) in thrombosis and inflammation on the context of coronary artery disease is currently being revised. In that perspective, we had studied the association of sCD40L with markers of platelet activation and markers of endothelial and vascular function. On that cohort, a stratification of patients with acute myocardial infarction (AMI) 1 month after percutaneous coronary intervention (PCI) was observed based on concentrations of sCD40L. The study intended to identify the groups of AMI patients with different profiles of sCD40L concentrations and verify how medication, clinical evolution, biochemical data, and markers of regulation of endothelial function at genetic (endothelial nitric oxide synthase polymorphisms) and post-transcriptional levels (circulating microRNAs) affect sCD40L serum levels. Lower quartiles of sCD40L (<2.3 ng/mL) were associated with higher concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP), high frequency of G894T polymorphism, and altered expression of a set of microRNAs assumed to be involved in the regulation of endothelial and cardiac function and myocardium hypertrophy, relative to patients in sCD40L upper quartiles. A characteristic sCD40L variation pattern in STEMI patients was identified. Low levels of sCD40L 1 month after PCI distinguish STEMI patients with worse prognosis, a compromised cardiac healing, and a persistent endothelial dysfunction, as given by the association between sCD40L, NT-proBNP, G894T polymorphism, and specific profile of miRNA expression. These results suggest sCD40L could have a prognostic value in STEMI patients.info:eu-repo/semantics/publishedVersio
Stabilisation of Clay Mixtures and Soils by Alkali Activation
Alkali activation of clay minerals in soil can be used to form a stabilising phase, such as a geopolymer. Because this requires low-temperature curing, typically <100 °C, it has the potential to be a lower-energy method than fired brick or even cement or lime stabilisation. Whilst this has been demonstrated for individual clay minerals and soils, it is unknown how effective this stabilisation method is for naturally occurring soils from around the world. The potential for stabilisation by alkali activation of a given clay mixture or soil could be approximately, but not fully, predicted from its clay mineralogical composition
Effectiveness of Motivational Interviewing in improving lipid level in patients with dyslipidemia assisted by general practitioners: Dislip-EM study protocol
<p>Abstract</p> <p>Background</p> <p>The non-pharmacological approach to cholesterol control in patients with hyperlipidemia is based on the promotion of a healthy diet and physical activity. Thus, to help patients change their habits, it is essential to identify the most effective approach. Many efforts have been devoted to explain changes in or adherence to specific health behaviors. Such efforts have resulted in the development of theories that have been applied in prevention campaigns, and that include brief advice and counseling services. Within this context, Motivational Interviewing has proven to be effective in changing health behaviors in specific cases. However, more robust evidence is needed on the effectiveness of Motivational Interviewing in treating chronic pathologies -such as dyslipidemia- in patients assisted by general practitioners. This article describes a protocol to assess the effectiveness of MI as compared with general practice (brief advice), with the aim of improving lipid level control in patients with dyslipidemia assisted by a general practitioner.</p> <p>Methods/Design</p> <p>An open, two-arm parallel, multicentre, cluster, controlled, randomized, clinical trial will be performed. A total of 48-50 general practitioners from 35 public primary care centers in Spain will be randomized and will recruit 436 patients with dyslipidemia. They will perform an intervention based either on Motivational Interviewing or on the usual brief advice. After an initial assessment, follow-ups will be performed at 2, 4, 8 and 12 months. Primary outcomes are lipid levels (total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) and cardiovascular risk. The study will assess the degree of dietary and physical activity improvement, weight loss in overweight patients, and adherence to treatment guidelines.</p> <p>Discussion</p> <p>Motivational interview skills constitute the primary strategies GPs use to treat their patients. Having economical, simple, effective and applicable techniques is essential for primary care professionals to help their patients change their lifestyle and improve their health. This study will provide scientific evidence on the effectiveness of Motivational interviewing, and will be performed under strict control over the data collected, ensuring the maintenance of therapeutic integrity.</p> <p>Trials Registration</p> <p>ClinicalTrials.gov (<a href="http://www.clinicaltrials.gov/ct2/show/NCT01282190">NCT01282190</a>).</p
Study on coinfecting vector-borne pathogens in dogs and ticks in Rio Grande do Norte, Brazil
Connexin channels and phospholipids: association and modulation
<p>Abstract</p> <p>Background</p> <p>For membrane proteins, lipids provide a structural framework and means to modulate function. Paired connexin hemichannels form the intercellular channels that compose gap junction plaques while unpaired hemichannels have regulated functions in non-junctional plasma membrane. The importance of interactions between connexin channels and phospholipids is poorly understood.</p> <p>Results</p> <p>Endogenous phospholipids most tightly associated with purified connexin26 or connexin32 hemichannels or with junctional plaques in cell membranes, those likely to have structural and/or modulatory effects, were identified by tandem electrospray ionization-mass spectrometry using class-specific interpretative methods. Phospholipids were characterized by headgroup class, charge, glycerol-alkyl chain linkage and by acyl chain length and saturation. The results indicate that specific endogenous phospholipids are uniquely associated with either connexin26 or connexin32 channels, and some phospholipids are associated with both. Functional effects of the major phospholipid classes on connexin channel activity were assessed by molecular permeability of hemichannels reconstituted into liposomes. Changes to phospholipid composition(s) of the liposome membrane altered the activity of connexin channels in a manner reflecting changes to the surface charge/potential of the membrane and, secondarily, to cholesterol content. Together, the data show that connexin26 and connexin32 channels have a preference for tight association with unique anionic phospholipids, and that these, independent of headgroup, have a positive effect on the activity of both connexin26 and connexin32 channels. Additionally, the data suggest that the likely in vivo phospholipid modulators of connexin channel structure-function that are connexin isoform-specific are found in the cytoplasmic leaflet. A modulatory role for phospholipids that promote negative curvature is also inferred.</p> <p>Conclusion</p> <p>This study is the first to identify (endogenous) phospholipids that tightly associate with connexin channels. The finding that specific phospholipids are associated with different connexin isoforms suggests connexin-specific regulatory and/or structural interactions with lipid membranes. The results are interpreted in light of connexin channel function and cell biology, as informed by current knowledge of lipid-protein interactions and membrane biophysics. The intimate involvement of distinct phospholipids with different connexins contributes to channel structure and/or function, as well as plaque integrity, and to modulation of connexin channels by lipophilic agents.</p
Molecular identification of Hepatozoon canis in dogs from Campo Grande, Mato Grosso do Sul, Brazil
Cytotoxic activities of new iron(III) and nickel(II) chelates of some S-methyl-thiosemicarbazones on K562 and ECV304 cells
The S-methyl-thiosemicarbazones of the 2-
hydroxy-R-benzaldehyde (R= H, 3-OH 3-OCH3 or 4-OCH3)
reacted with the corresponding aldehydes in the presence of
FeCl3 and NiCl2. New ONNO chelates of iron(III) and nickel
(II) with hydroxy- or methoxy-substitued N1,N4-diarylidene-Smethyl-
thiosemicarbazones were characterized by means of
elemental analysis, conductivity and magnetic measurements,
UV-Vis, IR and 1H-NMR spectroscopies. Cytotoxic activities
of the compounds were determined using K562 chronic
myeloid leukemia and ECV304 human endothelial cell lines
by MTT assay. It was determined that monochloro N1-4-
methoxysalicylidene-N4-4-methoxysalicylidene-S-methylthiosemicarbazidato-
iron(III) complex showed selective
anti-leukemic effects in K562 cells while has no effect in
ECV304 cells in the 0.53 μg/ml (IC50) concentrations. Also,
some methoxy-substitued nickel(II) chelates exhibit high
cytotoxic activitiy against both of these cell lines in low
concentrations. Cytotoxicity data were evaluated depending on
cell lines origin and position of the substituents on aromatic rings
Evaluation of appendicitis risk prediction models in adults with suspected appendicitis
Background
Appendicitis is the most common general surgical emergency worldwide, but its diagnosis remains challenging. The aim of this study was to determine whether existing risk prediction models can reliably identify patients presenting to hospital in the UK with acute right iliac fossa (RIF) pain who are at low risk of appendicitis.
Methods
A systematic search was completed to identify all existing appendicitis risk prediction models. Models were validated using UK data from an international prospective cohort study that captured consecutive patients aged 16–45 years presenting to hospital with acute RIF in March to June 2017. The main outcome was best achievable model specificity (proportion of patients who did not have appendicitis correctly classified as low risk) whilst maintaining a failure rate below 5 per cent (proportion of patients identified as low risk who actually had appendicitis).
Results
Some 5345 patients across 154 UK hospitals were identified, of which two‐thirds (3613 of 5345, 67·6 per cent) were women. Women were more than twice as likely to undergo surgery with removal of a histologically normal appendix (272 of 964, 28·2 per cent) than men (120 of 993, 12·1 per cent) (relative risk 2·33, 95 per cent c.i. 1·92 to 2·84; P < 0·001). Of 15 validated risk prediction models, the Adult Appendicitis Score performed best (cut‐off score 8 or less, specificity 63·1 per cent, failure rate 3·7 per cent). The Appendicitis Inflammatory Response Score performed best for men (cut‐off score 2 or less, specificity 24·7 per cent, failure rate 2·4 per cent).
Conclusion
Women in the UK had a disproportionate risk of admission without surgical intervention and had high rates of normal appendicectomy. Risk prediction models to support shared decision‐making by identifying adults in the UK at low risk of appendicitis were identified
How should I treat severe symptomatic aortic stenosis with transcatheter aortic valve implantation in a patient with right aortic arch?
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