Symptomatic aortic stenosis has a poor prognosis. Many patients are considered inoperable or at high surgical risk for surgical aortic valve replacement (SAVR), reflecting their age, comorbidities ...and frailty. The clinical effectiveness and safety of TAVI have not been reviewed systematically for these high levels of surgical risk. This systematic review compares mortality and other important clinical outcomes up to 5 years post treatment following TAVI or other treatment in these risk groups.
A systematic review protocol was registered on the PROSPERO database (CRD42016048396). The Cochrane Library, Centre for Reviews and Dissemination Databases, MEDLINE, EMBASE, and ZETOC were searched from January 2002 to August 2016. Clinical trials or matched studies comparing TAVI with other treatments for AS in patients surgically inoperable or operable at a high risk were included. Data extraction and quality assessment were conducted by two reviewers. Data were pooled using random-effects meta-analysis. The main outcomes were all-cause mortality, efficacy and major complications.
Three good quality randomised controlled trials (RCTs) were included. Patients' mean age ranged from 83-85 years, around half were female and New York Heart Association (NYHA) functional class III or IV ranged from 83.8% to 94.2% with frequent comorbidities. In 358 surgically inoperable patients from one RCT, TAVI was superior to medical therapy for all-cause mortality at 1 year (hazard ratio (HR) 0.58, 95% confidence interval (CI) 0.36-0.92), 2 years (HR 0.50, 95% CI 0.39-0.65), 3 years (HR 0.53, 95% CI 0.41to 0.68) and 5 years (HR 0.50, 95% CI 0.39-0.65), and NYHA class III or IV at 2 years (TAVI 16.8% (16/95), medical therapy 57.5% (23/40), p<0.001), quality of life and re-hospitalisation. TAVI had higher risks of major bleeding up to 1 year, of stroke up to 3 years (at one year 11.2% versus 5.5%, p = .06; HR at 2 years 2.79, 95% CI 1.25-6.22; HR at 3 years 2.81; 95% CI 1.26-6.26) and of major vascular complication at 3 years (HR 8.27, 95% CI 2.92-23.44). Using the GRADE tool, this evidence was considered to be of moderate quality. In a meta-analysis including 1,494 high risk surgically operable patients from two non-inferiority RCTs TAVI showed no significant differences from SAVR in all-cause mortality at two years (HR 1.03, 95% CI 0.82-1.29) and up to 5 years (HR 0.83, 95% CI 0.83-1.12). There were no statistically significant differences in major vascular complications and myocardial infarction at any time point, discrepant results for major bleeding on variable definitions and no differences in stroke rate at any time point. Using the GRADE tool, this evidence was considered of low quality.
Symptomatic aortic stenosis can be lethal without intervention but surgical resection is contraindicated for some patients and high risk for others. We found that all-cause mortality up to 5 years of follow-up did not differ significantly between TAVI and SAVR in patients surgically operable at a high risk, but favoured TAVI over medical therapy in patients surgically inoperable. TAVI is a viable life-extending treatment option in these surgical high risk groups.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Globally, over 33 million people have atrial fibrillation (AF). In eligible patients, oral anticoagulation (OAC) is recommended for stroke risk reduction. Despite recent increases in OAC prescribing, ...global under-prescription to high-risk AF patients and inappropriate prescription to low-risk patients is leading to unnecessary risk of stroke and haemorrhage. This meta-synthesis explored clinicians' beliefs and experiences regarding OAC prescription to AF patients, highlighting barriers to stroke prevention and informing future clinician-focused interventions.
A qualitative meta-synthesis exploring clinicians' views and experiences of prescribing OACs for stroke prevention in AF patients. Databases including MEDLINE, EMBASE, PsychINFO and CINAHL were searched to June 2018, with a further Medline search to February 2020. Thematic synthesis was performed with data coding, descriptive theme categorisation and generation of analytical themes. From 3499 records, 101 full text papers were screened, with 13 eligible studies identified. Four analytical themes were found to affect clinicians' prescribing: (i) 'Clinicians' intellectual and emotional responses to the evidence'; (ii) 'Prescribing in primary and secondary care'; (iii) 'Clinicians' views of how patients' characteristics and opinions influence prescribing'; and (iv) 'Clinicians' views on their interactions with patients'.
This review highlights focal points for future clinician-focused interventions to improve guideline-adherent OAC prescription in AF patients. Interventions should aim to improve clinicians' knowledge around NOAC prescription and stroke and haemorrhage risk assessment tools as well as their emotional responses to difficult prescribing scenarios. Multidisciplinary interventions promoting cohesive care and input from different clinicians to overcome time-related barriers may increase guideline-adherent OAC prescription for AF patients.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Patients with chronic kidney disease, especially those receiving hemodialysis (HD), are at risk of hyperkalemia (HK). This systematic review aimed to evaluate the prevalence of HK in patients with ...renal disease receiving HD and collate evidence on the effect of HK and differing HD patterns (i.e., long vs. short inter-dialytic intervals LIDI and SIDI, respectively in a thrice weekly schedule) on mortality.
Comprehensive searches were conducted across six databases and selected conference proceedings by two independent reviewers up to September 2020. A hundred and two studies reporting frequency of HK, mortality, or cardiovascular (CV) outcomes in adult patients with acute, chronic or end-stage renal disease in receipt of HD were included. Narrative synthesis of results was undertaken with key findings presented in tables and figures.
Median prevalence of HK in patients with renal disease receiving HD was 21.6% and increased in patients receiving concomitant medications - mainly renin-angiotensin-aldosterone system inhibitors and potassium-sparing diuretics. Associations between elevated potassium levels and increased risk of both all-cause and CV mortality in the HD population were consistent across the included studies. In addition, there was a rise in all-cause and CV mortality on the day following LIDI compared with the day after the two SIDIs in patients on HD.
Evidence identified in this systematic review indicates a relationship between HK and LIDI with mortality in patients with renal disease receiving HD, emphasizing the need for effective monitoring and management to control potassium levels both in emergency and chronic HD settings.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
OBJECTIVE—Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is a collagen receptor that belongs to the inhibitory immunoreceptor tyrosine-based inhibition motif–containing receptor family. ...It is an inhibitor of signaling via the immunoreceptor tyrosine-based activation motif–containing collagen receptor complex, glycoprotein VI-FcRγ-chain. It is expressed on hematopoietic cells, including immature megakaryocytes, but is not detectable on platelets. Although the inhibitory function of LAIR-1 has been described in leukocytes, its physiological role in megakaryocytes and in particular in platelet formation has not been explored. In this study, we investigate the role of LAIR-1 in megakaryocyte development and platelet production by generating LAIR-1–deficient mice.
APPROACH AND RESULTS—Mice lacking LAIR-1 exhibit a significant increase in platelet counts, a prolonged platelet half-life in vivo, and increased proplatelet formation in vitro. Interestingly, platelets from LAIR-1–deficient mice exhibit an enhanced reactivity to collagen and the glycoprotein VI–specific agonist collagen-related peptide despite not expressing LAIR-1, and mice showed enhanced thrombus formation in the carotid artery after ferric chloride injury. Targeted deletion of LAIR-1 in mice results in an increase in signaling downstream of the glycoprotein VI–FcRγ-chain and integrin αIIbβ3 in megakaryocytes because of enhanced Src family kinase activity.
CONCLUSIONS—Findings from this study demonstrate that ablation of LAIR-1 in megakaryocytes leads to increased Src family kinase activity and downstream signaling in response to collagen that is transmitted to platelets, rendering them hyper-reactive specifically to agonists that signal through Syk tyrosine kinases, but not to G-protein–coupled receptors.
Introduction
Respiratory syncytial virus (RSV) is an important cause of severe respiratory illness in older adults and adults with respiratory or cardiovascular comorbidities. Published estimates of ...its incidence and prevalence in adult groups vary widely. This article reviews the potential limitations affecting RSV epidemiology studies and suggests points to consider when evaluating or designing them.
Methods
Studies reporting the incidence or prevalence of RSV infection in adults in high-income Western countries from 2000 onwards were identified via a rapid literature review. Author-reported limitations were recorded, together with presence of other potential limitations. Data were synthesized narratively, with a focus on factors affecting incidence estimates for symptomatic infection in older adults.
Results
A total of 71 studies met the inclusion criteria, most in populations with medically attended acute respiratory illness (ARI). Only a minority used case definitions and sampling periods tailored specifically to RSV; many used influenza-based or other criteria that are likely to result in RSV cases being missed. The great majority relied solely on polymerase chain reaction (PCR) testing of upper respiratory tract samples, which is likely to miss RSV cases compared with dual site sampling and/or addition of serology. Other common limitations were studying a single season, which has potential for bias due to seasonal variability; failure to stratify results by age, which underestimates the burden of severe disease in older adults; limited generalizability beyond a limited study setting; and absence of measures of uncertainty in the reporting of results.
Conclusions
A significant proportion of studies are likely to underestimate the incidence of RSV infection in older adults, although the effect size is unclear and there is also potential for overestimation. Well-designed studies, together with increased testing for RSV in patients with ARI in clinical practice, are required to accurately capture both the burden of RSV and the potential public health impact of vaccines.
Post-translational modifications are necessary for collagen precursor molecules (procollagens) to acquire final shape and function. However, the mechanism and contribution of collagen modifications ...that occur outside the endoplasmic reticulum and Golgi are not understood. We discovered that VIPAR, with its partner proteins, regulate sorting of lysyl hydroxylase 3 (LH3, also known as PLOD3) into newly identified post-Golgi collagen IV carriers and that VIPAR-dependent sorting is essential for modification of lysines in multiple collagen types. Identification of structural and functional collagen abnormalities in cells and tissues from patients and murine models of the autosomal recessive multisystem disorder Arthrogryposis, Renal dysfunction and Cholestasis syndrome caused by VIPAR and VPS33B deficiencies confirmed our findings. Thus, regulation of post-Golgi LH3 trafficking is essential for collagen homeostasis and for the development and function of multiple organs and tissues.
Non-union affects up to 10% of fractures and is associated with substantial morbidity. There is currently no single effective therapy for the treatment or prevention of non-union. Potential ...treatments are currently selected for clinical trials based on results from limited animal studies, with no attempt to compare results between therapies to determine which have the greatest potential to treat non-union.
The aim of this systematic review was to define the range of therapies under investigation at the preclinical stage for the prevention or treatment of fracture non-union. Additionally, through meta-analysis, it aimed to identify the most promising therapies for progression to clinical investigation.
MEDLINE and Embase were searched from 1St January 2004 to 10th April 2017 for controlled trials evaluating an intervention to prevent or treat fracture non-union. Data regarding the model used, study intervention and outcome measures were extracted, and risk of bias assessed.
Of 5,171 records identified, 197 papers describing 204 therapies were included. Of these, the majority were only evaluated once (179/204, 88%), with chitosan tested most commonly (6/204, 3%). Substantial variation existed in model design, length of survival and duration of treatment, with results poorly reported. These factors, as well as a lack of consistently used objective outcome measures, precluded meta-analysis.
This review highlights the variability and poor methodological reporting of current non-union research. The authors call for a consensus on the standardisation of animal models investigating non-union, and suggest journals apply stringent criteria when considering animal work for publication.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Platelets are highly reactive cell fragments that adhere to exposed extracellular matrix (ECM) and prevent excessive blood loss by forming clots. Paradoxically, megakaryocytes, which produce ...platelets in the bone marrow, remain relatively refractory to the ECM-rich environment of the bone marrow despite having the same repertoire of receptors as platelets. These include the ITAM (immunoreceptor tyrosine-based activation motif)-containing collagen receptor complex, which consists of glycoprotein VI (GPVI) and the Fc receptor γ-chain, and the ITIM (immunoreceptor tyrosine-based inhibition motif)-containing receptor G6b-B. We showed that mice lacking G6b-B exhibited macrothrombocytopenia (reduced platelet numbers and the presence of enlarged platelets) and a susceptibility to bleeding as a result of aberrant platelet production and function. Platelet numbers were markedly reduced in G6b-B-deficient mice compared to those in wild-type mice because of increased platelet turnover. Furthermore, megakaryocytes in G6b-B-deficient mice showed enhanced metalloproteinase production, which led to increased shedding of cell-surface receptors, including GPVI and GPIbα. In addition, G6b-B-deficient megakaryocytes exhibited reduced integrin-mediated functions and defective formation of proplatelets, the long filamentous projections from which platelets bud off. Together, these findings establish G6b-B as a major inhibitory receptor regulating megakaryocyte activation, function, and platelet production.
A dynamic, properly organised actin cytoskeleton is critical for the production and haemostatic function of platelets. The Wiskott Aldrich Syndrome protein (WASp) and Actin-Related Proteins 2 & 3 ...Complex (Arp2/3 complex) are critical mediators of actin polymerisation and organisation in many cell types. In platelets and megakaryocytes, these proteins have been shown to be important for proper platelet production and function. The cortactin family of proteins (Cttn & HS1) are known to regulate WASp-Arp2/3-mediated actin polymerisation in other cell types and so here we address the role of these proteins in platelets using knockout mouse models.
We generated mice lacking Cttn and HS1 in the megakaryocyte/platelet lineage. These mice had normal platelet production, with platelet number, size and surface receptor profile comparable to controls. Platelet function was also unaffected by loss of Cttn/HS1 with no differences observed in a range of platelet function assays including aggregation, secretion, spreading, clot retraction or tyrosine phosphorylation. No effect on tail bleeding time or in thrombosis models was observed. In addition, platelet actin nodules, and megakaryocyte podosomes, actin-based structures known to be dependent on WASp and the Arp2/3 complex, formed normally. We conclude that despite the importance of WASp and the Arp2/3 complex in regulating F-actin dynamics in many cells types, the role of cortactin in their regulation appears to be fulfilled by other proteins in platelets.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Statins and antihypertensive agents are recommended for primary prevention of cardiovascular disease (CVD), but they are not always prescribed to eligible patients.
A systematic review of qualitative ...studies.
To explore health professionals' and patients' attitudes towards cardiovascular preventive drugs.
MEDLINE, Embase, PsychINFO, CINAHL, ASSIA, HMIC, Conference Proceedings Citation Index, and Open Grey were searched for studies of qualitative design without restrictions on date or language. Two reviewers performed study selection, data extraction, quality assessment, and thematic synthesis.
In total, 2585 titles and abstracts were screened, yielding 27 studies, of which five met eligibility criteria on full text assessment. These included 62 patients and 47 health professionals. Five themes emerged about patient attitudes: questioning preventive drugs; perceived benefit and risks, such as improving quality of life; patient preferences; trust in health professional judgement; and family, friends, and media influences. Five themes emerged about health professional attitudes: addressing patient concerns and information; duty as a health professional to prescribe; uncertainty about preventive drug prescribing; recognising consequences of prescribing, such as unnecessary medicalisation; and personalised treatment.
The attitudes of patients and health professionals regarding drug initiation for primary prevention reflect the complexity of the patient-health professional encounter in primary practice. For prescribing to be more adherent to guidelines, research should further investigate the patient-health professional relationship and the appropriate communication methods required when discussing drug initiation, specifically for primary prevention.
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