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Extracellular Matrix Molecules Facilitating Vascular Biointegration
All vascular implants, including stents, heart valves and graft materials exhibit suboptimal biocompatibility that significantly reduces their clinical efficacy. A range of biomolecules in the subendothelial space have been shown to play critical roles in local regulation of thrombosis, endothelial growth and smooth muscle cell proliferation, making these attractive candidates for modulation of vascular device biointegration. However, classically used biomaterial coatings, such as fibronectin and laminin, modulate only one of these components; enhancing endothelial cell attachment, but also activating platelets and triggering thrombosis. This review examines a subset of extracellular matrix molecules that have demonstrated multi-faceted vascular compatibility and accordingly are promising candidates to improve the biointegration of vascular biomaterials
Physiological predictors of acute coronary syndromes: emerging insights from the plaque to the vulnerable patient
In this review, the authors explore the evolving evidence linking physiological assessment of coronary artery disease with plaque progression and vulnerability. Reducing adverse clinical events remains the ultimate goal for diagnostic tests, and this review highlights evidence supporting the prognostic value of physiological metrics in predicting outcomes. Historical and contemporary studies support synergy among lesion severity, ischemia, plaque vulnerability, and patient prognosis. Ischemia contributes to clinical events through association with plaque burden, but this review addresses the emerging concept that it associates with atherothrombosis via disturbed lesion hemodynamics. Biomechanical pathophysiological forces including endothelial shear stress-the frictional force generated by blood flow on the vessel wall-are increasingly linked with atherogenesis, vulnerable plaque morphology, and platelet and leukocyte activation. The authors conclude by transitioning from the model of the vulnerable plaque to the concept of the "vulnerable patient," looking more broadly at physiological contributors to Virchow's triad underpinning acute coronary syndrome
The regulation of miRNAs by reconstituted high-density lipoproteins in diabetes-impaired angiogenesis
Diabetic vascular complications are associated with impaired ischaemia-driven angiogenesis. We recently found that reconstituted high-density lipoproteins (rHDL) rescue diabetes-impaired angiogenesis. microRNAs (miRNAs) regulate angiogenesis and are transported within HDL to sites of injury/repair. The role of miRNAs in the rescue of diabetes-impaired angiogenesis by rHDL is unknown. Using a miRNA array, we found that rHDL inhibits hsa-miR-181c-5p expression in vitro and using a hsa-miR-181c-5p mimic and antimiR identify a novel anti-angiogenic role for miR-181c-5p. miRNA expression was tracked over time post-hindlimb ischaemic induction in diabetic mice. Early post-ischaemia when angiogenesis is important, rHDL suppressed hindlimb mmu-miR-181c-5p. mmu-miR-181c-5p was not detected in the plasma or within HDL, suggesting rHDL specifically targets mmu-miR-181c-5p at the ischaemic site. Three known angiogenic miRNAs (mmu-miR-223-3p, mmu-miR-27b-3p, mmu-miR-92a-3p) were elevated in the HDL fraction of diabetic rHDL-infused mice early post-ischaemia. This was accompanied by a decrease in plasma levels. Only mmu-miR-223-3p levels were elevated in the hindlimb 3 days post-ischaemia, indicating that rHDL regulates mmu-miR-223-3p in a time-dependent and site-specific manner. The early regulation of miRNAs, particularly miR-181c-5p, may underpin the rescue of diabetes-impaired angiogenesis by rHDL and has implications for the treatment of diabetes-related vascular complications
A sex-specific role for androgens in angiogenesis
Mounting evidence suggests that in men, serum levels of testosterone are negatively correlated to cardiovascular and all-cause mortality. We studied the role of androgens in angiogenesis, a process critical in cardiovascular repair/regeneration, in males and females. Androgen exposure augmented key angiogenic events in vitro. Strikingly, this occurred in male but not female endothelial cells (ECs). Androgen receptor (AR) antagonism or gene knockdown abrogated these effects in male ECs. Overexpression of AR in female ECs conferred androgen sensitivity with respect to angiogenesis. In vivo, castration dramatically reduced neovascularization of Matrigel plugs. Androgen treatment fully reversed this effect in male mice but had no effect in female mice. Furthermore, orchidectomy impaired blood-flow recovery from hindlimb ischemia, a finding rescued by androgen treatment. Our findings suggest that endogenous androgens modulate angiogenesis in a sex-dependent manner, with implications for the role of androgen replacement in men
Consensus document for invasive coronary physiologic assessment in Asia-Pacific countries
Background: Currently, invasive physiologic assessment such as fractional flow reserve is widely used worldwide with different adoption rates around the globe. Patient characteristics and physician preferences often differ in the Asia-Pacific (APAC) region with respect to treatment strategy, techniques, lesion complexity, access to coronary physiology and imaging devices, as well as patient management. Thus, there is a need to construct a consensus document on recommendations for use of physiology-guided percutaneous coronary intervention (PCI) in APAC populations. This document serves as an overview of recommendations describing the best practices for APAC populations to achieve more consistent and optimal clinical outcomes.Â
Methods and Results: A comprehensive multiple-choice questionnaire was provided to 20 interven- tional cardiologists from 10 countries in the APAC region. Clinical evidence, tips and techniques, and clinical situations for the use of physiology-guided PCI in APAC were reviewed and used to propose key recommendations. There are suggestions to continue to develop evidence for lesion and patient types that will benefit from physiology, develop directions for future research in health economics and local data, develop appropriate use criteria in different countries, and emphasize the importance of education of all stakeholders. A consensus recommendation to enhance the penetration of invasive physiology-based therapy was to adopt the 5E approach: Evidence, Education, Expand hardware, Economics and Expert consensus.Â
Conclusions: This consensus document and recommendations support interventional fellows and cardiologists, hospital administrators, patients, and medical device companies to build confidence and encourage wider implementation of invasive coronary physiology-guided therapy in the APAC region.
Using meta-analytic path analysis to test theoretical predictions in health behavior: An illustration based on meta-analyses of the theory of planned behavior
Objective: Synthesizing research on social cognitive theories applied to health behavior is an important step in the development of an evidence base of psychological factors as targets for effective behavioral interventions. However, few meta-analyses of research on social cognitive theories in health contexts have conducted simultaneous tests of theoretically-stipulated pattern effects using path analysis. We argue that conducting path analyses of meta-analytic effects among constructs from social cognitive theories is important to test nomological validity, account for mediation effects, and evaluate unique effects of theory constructs independent of past behavior. We illustrate our points by conducting new analyses of two meta-analyses of a popular theory applied to health behaviors, the theory of planned behavior. Method: We conducted meta-analytic path analyses of the theory in two behavioral contexts (alcohol and dietary behaviors) using data from the primary studies included in the original meta-analyses augmented to include intercorrelations among constructs and relations with past behavior missing from the original analysis. Results: Findings supported the nomological validity of the theory and its hypotheses for both behaviors, confirmed important model processes through mediation analysis, demonstrated the attenuating effect of past behavior on theory relations, and provided estimates of the unique effects of theory constructs independent of past behavior. Conclusions: Our analysis illustrates the importance of conducting a simultaneous test of theory-stipulated effects in meta-analyses of social cognitive theories applied to health behavior. We recommend researchers adopt this analytic procedure when synthesizing evidence across primary tests of social cognitive theories in health
A systematic approach to the evaluation of the coronary microcirculation using bolus thermodilution: CATH CMD
Coronary microvascular dysfunction (CMD) can cause myocardial ischemia in patients presenting with angina without obstructive coronary artery disease (ANOCA). Evaluating for CMD by using the thermodilution technique offers a widely accessible means of assessing microvascular resistance. Through this technique, 2 validated indices, namely coronary flow reserve and the index of microcirculatory resistance, can be computed, facilitating investigation of the coronary microcirculation. The index of microcirculatory resistance specifically estimates minimum achievable microvascular resistance within the coronary microcirculation. We aim to review the bolus thermodilution method, outlining the fundamental steps for conducting measurements and introducing an algorithmic approach (CATH CMD) to systematically evaluate the coronary microcirculation. Embracing a standardized approach, exemplified by the CATH CMD algorithm, will facilitate adoption of this technique and streamline the diagnosis of CMD
ALPK1 missense pathogenic variant in five families leads to ROSAH syndrome, an ocular multisystem autosomal dominant disorder
Purpose: To identify the molecular cause in five unrelated families
with a distinct autosomal dominant ocular systemic disorder we
called ROSAH syndrome due to clinical features of retinal dystrophy,
optic nerve edema, splenomegaly, anhidrosis, and migraine headache.
Methods: Independent discovery exome and genome sequencing
in families 1, 2, and 3, and confirmation in families 4 and 5.
Expression of wild-type messenger RNA and protein in human and
mouse tissues and cell lines. Ciliary assays in fibroblasts from
affected and unaffected family members.
Results: We found the heterozygous missense variant in the Ékinase gene, ALPK1, (c.710C>T, [p.Thr237Met]), segregated with
disease in all five families. All patients shared the ROSAH
phenotype with additional low-grade ocular inflammation, pancytopenia, recurrent infections, and mild renal impairment in some.
ALPK1 was notably expressed in retina, retinal pigment epithelium,
and optic nerve, with immunofluorescence indicating localization
to the basal body of the connecting cilium of the photoreceptors,
and presence in the sweat glands. Immunocytofluorescence
revealed expression at the centrioles and spindle poles during
metaphase, and at the base of the primary cilium. Affected family
member fibroblasts demonstrated defective ciliogenesis.
Conclusion: Heterozygosity for ALPK1, p.Thr237Met leads to
ROSAH syndrome, an autosomal dominant ocular systemic
disorder
Development of an international standard set of patient-centred outcome measures for overall paediatric health: a consensus process
Objective: To develop an Overall Pediatric Health Standard Set (OPH-SS) of outcome measures that captures what matters to young people and their families and recognising the biopsychosocial aspects of health for all children and adolescents regardless of health condition. Design: A modified Delphi process. Setting: The International Consortium for Health Outcomes Measurement convened an international Working Group (WG) comprised of 23 international experts from 12 countries in the field of paediatrics, family medicine, psychometrics as well as patient advisors. The WG participated in 11 video-conferences, through a modified Delphi process and 9 surveys between March 2018 and January 2020 consensus was reached on a final recommended health outcome standard set. By a literature review conducted in March 2018, 1136 articles were screened for clinician and patient-reported or proxy-reported outcomes. Further, 4315 clinical trials and 12 paediatric health surveys were scanned. Between November 2019 and January 2020, the final standard set was endorsed by a patient validation (n=270
Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial
Background: Tranexamic acid reduces surgical bleeding and reduces death due to bleeding in patients with trauma.
Meta-analyses of small trials show that tranexamic acid might decrease deaths from gastrointestinal bleeding. We
aimed to assess the effects of tranexamic acid in patients with gastrointestinal bleeding.
Methods: We did an international, multicentre, randomised, placebo-controlled trial in 164 hospitals in 15 countries.
Patients were enrolled if the responsible clinician was uncertain whether to use tranexamic acid, were aged above the
minimum age considered an adult in their country (either aged 16 years and older or aged 18 years and older), and
had significant (defined as at risk of bleeding to death) upper or lower gastrointestinal bleeding. Patients were
randomly assigned by selection of a numbered treatment pack from a box containing eight packs that were identical
apart from the pack number. Patients received either a loading dose of 1 g tranexamic acid, which was added to
100 mL infusion bag of 0·9% sodium chloride and infused by slow intravenous injection over 10 min, followed by a
maintenance dose of 3 g tranexamic acid added to 1 L of any isotonic intravenous solution and infused at 125 mg/h
for 24 h, or placebo (sodium chloride 0·9%). Patients, caregivers, and those assessing outcomes were masked to
allocation. The primary outcome was death due to bleeding within 5 days of randomisation; analysis excluded patients
who received neither dose of the allocated treatment and those for whom outcome data on death were unavailable.
This trial was registered with Current Controlled Trials, ISRCTN11225767, and ClinicalTrials.gov, NCT01658124.
Findings: Between July 4, 2013, and June 21, 2019, we randomly allocated 12 009 patients to receive tranexamic acid
(5994, 49·9%) or matching placebo (6015, 50·1%), of whom 11 952 (99·5%) received the first dose of the allocated
treatment. Death due to bleeding within 5 days of randomisation occurred in 222 (4%) of 5956 patients in the
tranexamic acid group and in 226 (4%) of 5981 patients in the placebo group (risk ratio [RR] 0·99, 95% CI 0·82â1·18).
Arterial thromboembolic events (myocardial infarction or stroke) were similar in the tranexamic acid group and
placebo group (42 [0·7%] of 5952 vs 46 [0·8%] of 5977; 0·92; 0·60 to 1·39). Venous thromboembolic events (deep vein
thrombosis or pulmonary embolism) were higher in tranexamic acid group than in the placebo group (48 [0·8%] of
5952 vs 26 [0·4%] of 5977; RR 1·85; 95% CI 1·15 to 2·98).
Interpretation: We found that tranexamic acid did not reduce death from gastrointestinal bleeding. On the basis of our
results, tranexamic acid should not be used for the treatment of gastrointestinal bleeding outside the context of a
randomised trial
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