| 1. |
- Gregson, J., et al.
(author)
-
Cardiovascular Risk Factors Associated With Venous Thromboembolism
- 2019
-
In: JAMA Cardiology. - : American Medical Association (AMA). - 0965-2590 .- 2380-6583 .- 2380-6591. ; 4:2, s. 163-173
-
Journal article (peer-reviewed)abstract
- IMPORTANCE It is uncertain to what extent established cardiovascular risk factors are associated with venous thromboembolism (VTE). OBJECTIVE To estimate the associations of major cardiovascular risk factors with VTE, ie, deep vein thrombosis and pulmonary embolism. DESIGN, SETTING, AND PARTICIPANTS This study included individual participant data mostly from essentially population-based cohort studies from the Emerging Risk Factors Collaboration (ERFC; 731728 participants; 75 cohorts; years of baseline surveys, February 1960 to June 2008; latest date of follow-up, December 2015) and the UK Biobank (421537 participants; years of baseline surveys, March 2006 to September 2010; latest date of follow-up, February 2016). Participants without cardiovascular disease at baseline were included. Data were analyzed from June 2017 to September 2018. MAIN OUTCOMES AND MEASURES Hazard ratios (HRs) per 1-SD higher usual risk factor levels (or presence/absence). Incident fatal outcomes in ERFC (VTE, 1041; coronary heart disease [CND], 25131) and incident fatal/nonfatal outcomes in UK Biobank (VTE, 2321; CHD, 3385). Hazard ratios were adjusted for age, sex, smoking status, diabetes, and body mass index (BMI). RESULTS Of the 731728 participants from the ERFC. 403 396 (55.1%) were female, and the mean (SD) age at the time of the survey was 51.9 (9.0) years; of the 421537 participants from the UK Biobank, 233 699 (55.4%) were female, and the mean (SD) age at the time of the survey was 56.4 (8.1) years. Risk factors for VTE included older age (ERFC: HR per decade, 2.67; 95% CI, 2.45-2.91; UK Biobank: HR, 1.81; 95% CI, 1.71-1.92), current smoking (ERFC: HR, 1.38; 95% CI, 1.20-1.58; UK Biobank: HR, 1.23; 95% CI, 1.08-1.40), and BMI (ERFC: HR per 1-SD higher BMI, 1.43; 95% CI, 1.35-1.50; UK Biobank: HR, 1.37; 95% CI, 1.32-1.41). For these factors, there were similar HRs for pulmonary embolism and deep vein thrombosis in UK Biobank (except adiposity was more strongly associated with pulmonary embolism) and similar HRs for unprovoked vs provoked VTE. Apart from adiposity, these risk factors were less strongly associated with VTE than CHD. There were inconsistent associations of VTEs with diabetes and blood pressure across ERFC and UK Biobank, and there was limited ability to study lipid and inflammation markers. CONCLUSIONS AND RELEVANCE Older age, smoking, and adiposity were consistently associated with higher VTE risk.
|
|
| 2. |
- Jones, Gregory T., et al.
(author)
-
Meta-Analysis of Genome-Wide Association Studies for Abdominal Aortic Aneurysm Identifies Four New Disease-Specific Risk Loci
- 2017
-
In: Circulation Research. - 0009-7330 .- 1524-4571. ; 120:2, s. 341-
-
Journal article (peer-reviewed)abstract
- Rationale: Abdominal aortic aneurysm (AAA) is a complex disease with both genetic and environmental risk factors. Together, 6 previously identified risk loci only explain a small proportion of the heritability of AAA. Objective: To identify additional AAA risk loci using data from all available genome-wide association studies. Methods and Results: Through a meta-analysis of 6 genome-wide association study data sets and a validation study totaling 10 204 cases and 107 766 controls, we identified 4 new AAA risk loci: 1q32.3 (SMYD2), 13q12.11 (LINC00540), 20q13.12 (near PCIF1/MMP9/ZNF335), and 21q22.2 (ERG). In various database searches, we observed no new associations between the lead AAA single nucleotide polymorphisms and coronary artery disease, blood pressure, lipids, or diabetes mellitus. Network analyses identified ERG, IL6R, and LDLR as modifiers of MMP9, with a direct interaction between ERG and MMP9. Conclusions: The 4 new risk loci for AAA seem to be specific for AAA compared with other cardiovascular diseases and related traits suggesting that traditional cardiovascular risk factor management may only have limited value in preventing the progression of aneurysmal disease.
|
|
| 3. |
- Bentley, Michael J., et al.
(author)
-
A community-based geological reconstruction of Antarctic Ice Sheet deglaciation since the Last Glacial Maximum
- 2014
-
In: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 100, s. 1-9
-
Journal article (peer-reviewed)abstract
- A robust understanding of Antarctic Ice Sheet deglacial history since the Last Glacial Maximum is important in order to constrain ice sheet and glacial-isostatic adjustment models, and to explore the forcing mechanisms responsible for ice sheet retreat. Such understanding can be derived from a broad range of geological and glaciological datasets and recent decades have seen an upsurge in such data gathering around the continent and Sub-Antarctic islands. Here, we report a new synthesis of those datasets, based on an accompanying series of reviews of the geological data, organised by sector. We present a series of timeslice maps for 20 ka, 15 ka, 10 ka and 5 ka, including grounding line position and ice sheet thickness changes, along with a clear assessment of levels of confidence. The reconstruction shows that the Antarctic Ice sheet did not everywhere reach the continental shelf edge at its maximum, that initial retreat was asynchronous, and that the spatial pattern of deglaciation was highly variable, particularly on the inner shelf. The deglacial reconstruction is consistent with a moderate overall excess ice volume and with a relatively small Antarctic contribution to meltwater pulse la. We discuss key areas of uncertainty both around the continent and by time interval, and we highlight potential priorities for future work. The synthesis is intended to be a resource for the modelling and glacial geological community.
|
|
| 4. |
- Rowbotham, S. E., et al.
(author)
-
Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN) : Study protocol for a randomised controlled trial
- 2017
-
In: Trials. - : BioMed Central Ltd.. - 1745-6215. ; 18:1
-
Journal article (peer-reviewed)abstract
- Background: An abdominal aortic aneurysm (AAA) is a focal dilation of the abdominal aorta and is associated with a risk of fatal rupture. Experimental studies suggest that myo-inositol may exert beneficial effects on AAAs through favourable changes to biological pathways implicated in AAA pathology. The aim of the Inositol in the MAnaGemENt of abdominal aortic aneurysm (IMAGEN) trial is to assess if myo-inositol will reduce AAA growth. Methods/design: IMAGEN is a multi-centre, prospective, parallel-group, randomised, double-blind, placebo-controlled trial. A total of 164 participants with an AAA measuring ≥ 30 mm will be randomised to either 2 g of myo-inositol or identical placebo twice daily for 12 months. The primary outcome measure will be AAA growth estimated by increase in total infrarenal aortic volume measured on computed tomographic scans. Secondary outcome measures will include AAA diameter assessed by computed tomography and ultrasound, AAA peak wall stress and peak wall rupture index, serum lipids, circulating AAA biomarkers, circulating RNAs and health-related quality of life. All analysis will be based on the intention-to-treat principle at the time of randomisation. All patients who meet the eligibility criteria, provide written informed consent and are enrolled in the study will be included in the primary analysis, regardless of adherence to dietary allocation. Discussion: Currently, there is no known medical therapy to limit AAA progression. The IMAGEN trial will be the first randomised trial, to our knowledge, to assess the value of myo-inositol in limiting AAA growth.
|
|
| 5. |
- Belch, Jill J. F., et al.
(author)
-
Results of the randomized, placebo-controlled clopidogrel and acetylsalicylic acid in bypass surgery for peripheral arterial disease (CASPAR) trial
- 2010
-
In: Journal of vascular surgery : official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter. - : Elsevier BV. - 0741-5214. ; 52:4, s. 825-833, 833.e1-2
-
Journal article (peer-reviewed)abstract
- The combination of clopidogrel plus ASA did not improve limb or systemic outcomes in the overall population of PAD patients requiring below-knee bypass grafting. Subgroup analysis suggests that clopidogrel plus ASA confers benefit in patients receiving prosthetic grafts without significantly increasing major bleeding risk.
|
|
| 6. |
|
|
| 7. |
- Golledge, J., et al.
(author)
-
Lack of an effective drug therapy for abdominal aortic aneurysm
- 2020
-
In: Journal of Internal Medicine. - : WILEY. - 0954-6820 .- 1365-2796. ; 288:1, s. 6-22
-
Research review (peer-reviewed)abstract
- Abdominal aortic aneurysm (AAA) rupture is a common cause of death in adults. CurrentAAAtreatment is by open surgical or endovascular aneurysm repair. Rodent model and human epidemiology, and genetic and observational studies over the last few decades have highlighted the potential of a number of drug therapies, including medications that lower blood pressure, correct dyslipidaemia, or inhibit thrombosis, inflammation or matrix remodelling, as approaches to managing smallAAA. This review summarizes priorAAApathogenesis data from animal and human studies aimed at identifying targets for the development of drug therapies. The review also systematically assesses past randomized placebo-controlled drug trials in patients with smallAAAs. Eleven previously published randomized-controlled clinical trials testing different drug therapies aimed at slowingAAAprogression were identified. Five of the trials tested antibiotics and three trials assessed medications that lower blood pressure. Meta-analyses of these trials suggested that neither of these approaches limitAAAgrowth. Allocation to blood pressure-lowering medication was associated with a small reduction inAAArupture or repair, compared to placebo (relative risk 0.94, 95% confidence intervals 0.89, 1.00,P = 0.047). Three further trials assessed the effect of a mast cell inhibitor, fibrate or platelet aggregation inhibition and reported no effect onAAAgrowth or clinical events. Past trials were noted to have a number of design issues, particularly small sample sizes and limited follow-up. Much larger trials are needed to properly test potential therapeutic approaches if a convincingly effective medical therapy forAAAis to be identified.
|
|
| 8. |
- Nordanstig, Joakim, et al.
(author)
-
Peripheral arterial disease (PAD)-A challenging manifestation of atherosclerosis
- 2023
-
In: Preventive Medicine. - : Academic Press. - 0091-7435 .- 1096-0260. ; 171
-
Journal article (peer-reviewed)abstract
- The diagnosis of peripheral arterial disease (PAD) is not always evident as symptoms and signs may show great variation. As all grades of PAD are linked to both an increased risk for cardiovascular complications and adverse limb events, awareness of the condition and knowledge about diagnostic measures, prevention and treatment is crucial. This article presents in a condensed form information on PAD and its management.
|
|
| 9. |
- Singh, T. P., et al.
(author)
-
Comparison of peak wall stress and peak wall rupture index in ruptured and asymptomatic intact abdominal aortic aneurysms
- 2020
-
In: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 108:6, s. 652-658
-
Journal article (peer-reviewed)abstract
- Background: Previous studies have suggested that finite element analysis (FEA) can estimate the rupture risk of an abdominal aortic aneurysm (AAA); however, the value of biomechanical estimates over measurement of AAA diameter alone remains unclear. This study aimed to compare peak wall stress (PWS) and peak wall rupture index (PWRI) in participants with ruptured and asymptomatic intact AAAs. Methods: The reproducibility of semiautomated methods for estimating aortic PWS and PWRI from CT images was assessed. PWS and PWRI were estimated in people with ruptured AAAs and those with asymptomatic intact AAAs matched by orthogonal diameter on a 1 : 2 basis. Spearman's correlation coefficient was used to assess the association between PWS or PWRI and AAA diameter. Independent associations between PWS or PWRI and AAA rupture were identified by means of logistic regression analyses. Results: Twenty individuals were included in the analysis of reproducibility. The main analysis included 50 patients with an intact AAA and 25 with a ruptured AAA. Median orthogonal diameter was similar in ruptured and intact AAAs (82·3 (i.q.r. 73·5–92·0) versus 81·0 (73·2–92·4) mm respectively; P = 0·906). Median PWS values were 286·8 (220·2–329·6) and 245·8 (215·2–302·3) kPa respectively (P = 0·192). There was no significant difference in PWRI between the two groups (P = 0·982). PWS and PWRI correlated positively with orthogonal diameter (both P < 0·001). Participants with high PWS, but not PWRI, were more likely to have a ruptured AAA after adjusting for potential confounders (odds ratio 5·84, 95 per cent c.i. 1·22 to 27·95; P = 0·027). This association was not maintained in all sensitivity analyses. Conclusion: High aortic PWS had an inconsistent association with greater odds of aneurysm rupture in patients with a large AAA.
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
- Khosla, S., et al.
(author)
-
Meta-analysis of peak wall stress in ruptured, symptomatic and intact abdominal aortic aneurysms
- 2014
-
In: British Journal of Surgery. - : Oxford University Press (OUP). - 0007-1323 .- 1365-2168. ; 101:11, s. 1350-1357
-
Research review (peer-reviewed)abstract
- Background: Abdominal aortic aneurysm (AAA) is an important cause of sudden death; however, there are currently incomplete means to predict the risk of AAA rupture. AAA peak wall stress (PWS) can be estimated using finite element analysis (FEA) methods from computed tomography (CT) scans. The question is whether AAA PWS can predict AAA rupture. The aim of this systematic review was to compare PWS in patients with ruptured and intact AAA. Methods: The MEDLINE database was searched on 25 May 2013. Case-control studies assessing PWS in asymptomatic intact, and acutely symptomatic or ruptured AAA from CT scans using FEA were included. Data were extracted independently. A random-effects model was used to calculate standard mean differences (SMDs) for PWS measurements. Results: Nine studies assessing 348 individuals were identified and used in the meta-analysis. Results from 204 asymptomatic intact and 144 symptomatic or ruptured AAAs showed that PWS was significantly greater in the symptomatic/ruptured AAAs compared with the asymptomatic intact AAAs (SMD 0.95, 95 per cent confidence interval 0. 71 to 1.18; P < 0. 001). The findings remained significant after adjustment for mean systolic blood pressure, standardized at 120 mmHg(SMD 0.68, 0.39 to 0.96; P < 0. 001). Minimal heterogeneity between studies was noted (I-2 = 0 per cent). Conclusion: This study suggests that PWS is greater in symptomatic or ruptured AAA than in asymptomatic intact AAA.
|
|
| 13. |
- Neuen, B. L., et al.
(author)
-
Factors Associated with Patency Following Angioplasty of Hemodialysis Fistulae
- 2014
-
In: Journal of Vascular and Interventional Radiology. - : Elsevier BV. - 1051-0443. ; 25:9, s. 1419-1426
-
Journal article (peer-reviewed)abstract
- Purpose: Patency after percutaneous transluminal angioplasty of native hemodialysis arteriovenous fistulae (AVFs) is highly variable. This study aimed to identify predictors of patency following angioplasty in native AVFs. Materials and Methods: All endovascular procedures performed in native AVFs between 2005 and 2013 at two institutions were retrospectively reviewed. Clinical, anatomic, biochemical, and medication variables Were subjected to univariate and multivariate Cox regression analysis to identify predictors of postintervention primary and secondary patency. Results: During the study period, 207 patients underwent first angioplasty of their AVF. Follow-up ranged from 14 days to 8 years, during which another 247 endovascular interventions were performed to maintain patency. Postintervention primary patency rates at 6, 12, and 24 months were 66%, 49%, and 29%, respectively. Postintervention secondary patency rates at 6, 12, and 24 months were 94%, 84%, and 79%, respectively. On multivariate adjusted Cox regression analysis, upper-arm AVFs (P = .00072), AVFs less than 6 months of age (P = .0014), presence of multiple stenoses (P = .019), and degree of initial stenosis (P = .016) were significantly associated with shorter postintervention primary patency. A previously failed AVF was the only significant predictor of postintervention secondary patency loss (P = .0053). Conclusions: Anatomic factors related to the AVF location, AVF age, and the extent of the lesion are important predictors of restenosis after balloon angioplasty. Traditional cardiovascular risk factors, metabolic and inflammatory markers, and medications were not associated with postintervention potency.
|
|
| 14. |
- Rainsley, Eleanor, et al.
(author)
-
Pleistocene glacial history of the New Zealand subantarctic islands
- 2019
-
In: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 15:2, s. 423-448
-
Journal article (peer-reviewed)abstract
- The New Zealand subantarctic islands of Auckland and Campbell, situated between the subtropical front and the Antarctic Convergence in the Pacific sector of the Southern Ocean, provide valuable terrestrial records from a globally important climatic region. Whilst the islands show clear evidence of past glaciation, the timing and mechanisms behind Pleistocene environmental and climate changes remain uncertain. Here we present a multidisciplinary study of the islands-including marine and terrestrial geomorphological surveys, extensive analyses of sedimentary sequences, a comprehensive dating programme, and glacier flow line modelling-to investigate multiple phases of glaciation across the islands. We find evidence that the Auckland Islands hosted a small ice cap 384 000 +/- 26 000 years ago (384 +/- 26 ka), most likely during Marine Isotope Stage 10, a period when the subtropical front was reportedly north of its present-day latitude by several degrees, and consistent with hemispheric-wide glacial expansion. Flow line modelling constrained by field evidence suggests a more restricted glacial period prior to the LGM that formed substantial valley glaciers on the Campbell and Auckland Islands around 72-62 ka. Despite previous interpretations that suggest the maximum glacial extent occurred in the form of valley glaciation at the Last Glacial Maximum (LGM; similar to 21 ka), our combined approach suggests minimal LGM glaciation across the New Zealand subantarctic islands and that no glaciers were present during the Antarctic Cold Reversal (ACR; similar to 15-13 ka). Instead, modelling implies that despite a regional mean annual air temperature depression of similar to 5 degrees C during the LGM, a combination of high seasonality and low precipitation left the islands incapable of sustaining significant glaciation. We suggest that northwards expansion of winter sea ice during the LGM and subsequent ACR led to precipitation starvation across the middle to high latitudes of the Southern Ocean, resulting in restricted glaciation of the subantarctic islands.
|
|
| 15. |
|
|
| 16. |
- Singh, T. P., et al.
(author)
-
Systematic review and meta-analysis of the association between intraluminal thrombus volume and abdominal aortic aneurysm rupture
- 2019
-
In: Journal of Vascular Surgery. - : Mosby Inc.. - 0741-5214 .- 1097-6809. ; 70:6, s. 2065--2073.e10
-
Research review (peer-reviewed)abstract
- Background: Intraluminal thrombus (ILT) is present in most abdominal aortic aneurysms (AAAs), although its role in AAA progression is controversial. Methods: A literature search was performed to identify studies that investigated the association between ILT volume and AAA rupture. A study assessment tool was developed to assess the methodologic quality of included studies. A meta-analysis was conducted using an inverse variance-weighted random-effects model to compare the ILT volume in ruptured and asymptomatic intact AAAs. Leave-one-out sensitivity analyses were conducted to assess the robustness of the findings. A subanalysis was performed including studies in which patients with asymptomatic intact and ruptured AAAs were matched for aortic diameter. Interstudy heterogeneity was assessed using the I2 statistic. Results: Eight studies involving 672 patients were included in this systematic review. Meta-analysis of all studies found a greater ILT volume in patients with ruptured AAAs than in patients with asymptomatic intact AAAs (standardized mean difference, 0.56; 95% confidence interval, 0.17-0.96; P =.005; I2 = 79.8%). Sensitivity analyses suggested that the findings were robust; however, aortic diameter was significantly larger in ruptured than in asymptomatic intact AAAs (mean ± standard deviation, 78 ± 18 and 64 ± 15 mm, respectively; P <.001). In the subanalysis of studies that matched for diameter, no significant difference in ILT volume between groups was found (standardized mean difference, 0.03; 95% confidence interval, −0.27 to 0.33; P =.824; I2 = 0%). Conclusions: This meta-analysis suggests that ILT volume is greater in patients with ruptured AAAs than in patients with asymptomatic intact AAAs, although this is most likely due to the larger diameter of ruptured AAAs.
|
|
| 17. |
- Turney, Chris S M, et al.
(author)
-
Rapid global ocean-atmosphere response to Southern Ocean freshening during the last glacial
- 2017
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8:1
-
Journal article (peer-reviewed)abstract
- Contrasting Greenland and Antarctic temperatures during the last glacial period (115,000 to 11,650 years ago) are thought to have been driven by imbalances in the rates of formation of North Atlantic and Antarctic Deep Water (the 'bipolar seesaw'). Here we exploit a bidecadally resolved 14C data set obtained from New Zealand kauri (Agathis australis) to undertake high-precision alignment of key climate data sets spanning iceberg-rafted debris event Heinrich 3 and Greenland Interstadial (GI) 5.1 in the North Atlantic (~30,400 to 28,400 years ago). We observe no divergence between the kauri and Atlantic marine sediment 14C data sets, implying limited changes in deep water formation. However, a Southern Ocean (Atlantic-sector) iceberg rafted debris event appears to have occurred synchronously with GI-5.1 warming and decreased precipitation over the western equatorial Pacific and Atlantic. An ensemble of transient meltwater simulations shows that Antarctic-sourced salinity anomalies can generate climate changes that are propagated globally via an atmospheric Rossby wave train.
|
|
| 18. |
- Watterson, William J., et al.
(author)
-
The roles of an aluminum underlayer in the biocompatibility and mechanical integrity of vertically aligned carbon nanotubes for interfacing with retinal neurons
- 2020
-
In: Micromachines. - 2072-666X. ; 11:6
-
Journal article (peer-reviewed)abstract
- Retinal implant devices are becoming an increasingly realizable way to improve the vision of patients blinded by photoreceptor degeneration. As an electrode material that can improve restored visual acuity, carbon nanotubes (CNTs) excel due to their nanoscale topography, flexibility, surface chemistry, and double-layer capacitance. If vertically aligned carbon nanotubes (VACNTs) are biocompatible with retinal neurons and mechanically robust, they can further improve visual acuity-most notably in subretinal implants-because they can be patterned into high-aspect-ratio, micrometer-size electrodes. We investigated the role of an aluminum (Al) underlayer beneath an iron (Fe) catalyst layer used in the growth of VACNTs by chemical vapor deposition (CVD). In particular, we cultured dissociated retinal cells for three days in vitro (DIV) on unfunctionalized and oxygen plasma functionalized VACNTs grown from a Fe catalyst (Fe and Fe + Pl preparations, where Pl signifies the plasma functionalization) and an Fe catalyst with an Al underlayer (Al/Fe and Al/Fe + Pl preparations). The addition of the Al layer increased the mechanical integrity of the VACNT interface and enhanced retinal neurite outgrowth over the Fe preparation. Unexpectedly, the extent of neurite outgrowth was significantly greater in the Al/Fe than in the Al/Fe+Pl preparation, suggesting plasma functionalization can negatively impact biocompatibility for some VACNT preparations. Additionally, we show our VACNT growth process for the Al/Fe preparation can support neurite outgrowth for up to 7 DIV. By demonstrating the retinal neuron biocompatibility, mechanical integrity, and pattern control of our VACNTs, this work offers VACNT electrodes as a solution for improving the restored visual acuity provided by modern retinal implants.
|
|
| 19. |
- Hendy, K., et al.
(author)
-
Growth rates of small abdominal aortic aneurysms assessed by computerised tomography - A systematic literature review
- 2014
-
In: Atherosclerosis. - : Elsevier BV. - 0021-9150. ; 235:1, s. 182-188
-
Research review (peer-reviewed)abstract
- Background: Most current evidence examining abdominal aortic aneurysm (AAA) growth is based on ultrasound surveillance. Objective: This review aimed to systematically analyse studies which have assessed small AAA growth using computed tomography (CT) to monitor outcome. Method: Studies investigating small AAA expansion rates using CT images were identified by searching the PubMed database and hand searching article reference lists. Eligible studies must have focused on monitoring small AAA growth using CT and included patients with baseline AAA diameters <55 mm for which growth rates were reported. Results: Ten studies including 845 patients met eligibility with average baseline AAA diameters ranging from 36.2 to 50.5 mm. AAA growth was assessed using axial (n = 1), orthogonal (n = 2), anterior to posterior (n = 4), and unspecified (n = 3) measurement methods. One study reported the reproducibility of their assessment method. Mean AAA diameter growth rates ranged from 2.6 to 5.2 mm/year. Factors reported to be associated with increased AAA expansion included: large AAA thrombus size (n = 3 studies), large baseline AAA diameter (n = 2), high AAA wall stress, elevated plasma concentration of matrix metalloproteinase-9 and presence of carotid artery disease (n = 1 study each). Factors reported to be negatively associated with AAA growth included presence of diabetes mellitus and chronic limb ischaemia (n = 1 study each). Conclusion: Many currently reported studies assessing small AAA growth on CT fail to report consistent use of reproducible measurement methods. CT offers the opportunity to assess orthogonal diameter and perform central reading which could be an advantage of this form of imaging. Crown Copyright (C) 2014 Published by Elsevier Ireland Ltd. All rights reserved.
|
|
| 20. |
- Hendy, K., et al.
(author)
-
Infra-renal abdominal aortic calcification volume does not predict small abdominal aortic aneurysm growth
- 2015
-
In: Atherosclerosis. - : Elsevier BV. - 0021-9150. ; 243:1, s. 334-338
-
Journal article (peer-reviewed)abstract
- Background: Vascular calcification is a common finding in abdominal aortic aneurysms (AAA) however whether it predicts aneurysm expansion is controversial. Objectives: 1) To establish a reproducible method of assessing AAA calcification using computed tomography (CT); 2) To investigate the association between AAA calcification and growth. Method: Patients were identified from a prospectively maintained small AAA surveillance database. To be included patients required at least two CT scans a minimum of 6 months apart. All patients had a maximal AAA diameter of <= 55 mm on their initial scan. Infra-renal aortic calcification volume, total infra-renal aortic volume and maximal AAA diameter were measured. Reproducibility was assessed from repeat scans performed on 31 patients. AAA growth, estimated by volume change per year, was compared between patients with baseline infra-renal aortic calcification volumes< and >= median. Results: 95% agreement limits (lower, upper) for intra and inter-observer error in measuring infra-renal aortic calcification volume were 0.68, 97 mm(3) and - 140, 5.8 mm(3), respectively. Concordance correlation coefficients for inter and intra-observer variability in measuring infra-renal aortic calcification volume were 0.99 and 0.99, respectively. Patients with infra-renal aortic calcification volume < median (n = 44) and >= median (n = 44) had an infra-renal aortic volume increase of 6.0 cm(3)/yr and 7.8 cm(3)/yr, respectively (p = 0.66). Mean percentage infra-renal aortic volume increase/yr was found to be 4.2 +/- 6.4 and 8.9 +/- 6.2 for patients with and without diabetes, respectively (p = 0.003). Conclusion: Infra-renal aortic calcification volume can be assessed reproducibly from CT images. Infrarenal aortic calcification volume did not predict small AAA growth. Crown Copyright (C) 2015 Published by Elsevier Ireland Ltd. All rights reserved.
|
|
| 21. |
- Jones, R. S., et al.
(author)
-
Rapid Holocene thinning of an East Antarctic outlet glacier driven by marine ice sheet instability
- 2015
-
In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 6
-
Journal article (peer-reviewed)abstract
- Outlet glaciers grounded on a bed that deepens inland and extends below sea level are potentially vulnerable to 'marine ice sheet instability'. This instability, which may lead to runaway ice loss, has been simulated in models, but its consequences have not been directly observed in geological records. Here we provide new surface-exposure ages from an outlet of the East Antarctic Ice Sheet that reveal rapid glacier thinning occurred approximately 7,000 years ago, in the absence of large environmental changes. Glacier thinning persisted for more than two and a half centuries, resulting in hundreds of metres of ice loss. Numerical simulations indicate that ice surface drawdown accelerated when the otherwise steadily retreating glacier encountered a bedrock trough. Together, the geological reconstruction and numerical simulations suggest that centennial-scale glacier thinning arose from unstable grounding line retreat. Capturing these instability processes in ice sheet models is important for predicting Antarctica's future contribution to sea level change.
|
|
| 22. |
|
|
| 23. |
- Martin, Maria A., et al.
(author)
-
Ten new insights in climate science 2021 : a horizon scan
- 2021
-
In: Global Sustainability. - : Cambridge University Press (CUP). - 2059-4798. ; 4, s. 1-20
-
Research review (peer-reviewed)abstract
- Non-technical summary: We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding about the remaining options to achieve the Paris Agreement goals, through overcoming political barriers to carbon pricing, taking into account non-CO2 factors, a well-designed implementation of demand-side and nature-based solutions, resilience building of ecosystems and the recognition that climate change mitigation costs can be justified by benefits to the health of humans and nature alone. We consider new insights about what to expect if we fail to include a new dimension of fire extremes and the prospect of cascading climate tipping elements.Technical summary: A synthesis is made of 10 topics within climate research, where there have been significant advances since January 2020. The insights are based on input from an international open call with broad disciplinary scope. Findings include: (1) the options to still keep global warming below 1.5 °C; (2) the impact of non-CO2 factors in global warming; (3) a new dimension of fire extremes forced by climate change; (4) the increasing pressure on interconnected climate tipping elements; (5) the dimensions of climate justice; (6) political challenges impeding the effectiveness of carbon pricing; (7) demand-side solutions as vehicles of climate mitigation; (8) the potentials and caveats of nature-based solutions; (9) how building resilience of marine ecosystems is possible; and (10) that the costs of climate change mitigation policies can be more than justified by the benefits to the health of humans and nature.Social media summary: How do we limit global warming to 1.5 °C and why is it crucial? See highlights of latest climate science.
|
|
| 24. |
- Neuen, B. L., et al.
(author)
-
Predictors of Patency after Balloon Angioplasty in Hemodialysis Fistulas: A Systematic Review
- 2014
-
In: Journal of Vascular and Interventional Radiology. - : Elsevier BV. - 1051-0443. ; 25:6, s. 917-924
-
Research review (peer-reviewed)abstract
- Percutaneous transluminal angioplasty (PTA) is an established treatment for dysfunctional hemodialysis fistulas. This article systematically reviews evidence for predictors of patency after PTA. Outcomes assessed were primary, assisted primary, and secondary patency after intervention, and findings were summarized descriptively. This review included 11 nonrandomized observational studies of 965 fistulas in 939 patients. Follow-up ranged from 0 days to 10 years. Study quality was overall Suboptimal. Newer fistulas and longer lesion length may be associated with primary potency loss after PTA. Further studies are needed to confirm these findings, to identify potentially modifiable factors, and to guide the testing of new endovascular devices.
|
|
| 25. |
- Thomas, Zoë A., et al.
(author)
-
Tipping elements and amplified polar warming during the Last Interglacial
- 2020
-
In: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791. ; 233
-
Research review (peer-reviewed)abstract
- Irreversible shifts of large-scale components of the Earth system (so-called ‘tipping elements’) on policy-relevant timescales are a major source of uncertainty for projecting the impacts of future climate change. The high latitudes are particularly vulnerable to positive feedbacks that amplify change through atmosphere-ocean-ice interactions. Unfortunately, the short instrumental record does not capture the full range of past or projected climate scenarios (a situation particularly acute in the high latitudes). Natural archives from past periods warmer than present day, however, can be used to explore drivers and responses to forcing, and provide data against which to test models, thereby offering insights into the future. The Last Interglacial (129–116,000 years before present) — the warmest interglacial of the last 800,000 years — was the most recent period during which global temperatures were comparable with low-end 21st Century projections (up to 2 °C warmer, with temperature increase amplified over polar latitudes), providing a potentially useful analogue for future change. Substantial environmental changes happened during this time. Here we synthesise the nature and timing of potential high-latitude tipping elements during the Last Interglacial, including sea ice, extent of the boreal forest, permafrost, ocean circulation, and ice sheets/sea level. We also review the thresholds and feedbacks that likely operated through this period. Notably, substantial ice mass loss from Greenland, the West Antarctic, and possibly sectors of the East Antarctic drove a 6–9 m rise in global sea level. This was accompanied by reduced summer sea-ice extent, poleward-extended boreal forest, and reduced areas of permafrost. Despite current chronological uncertainties, we find that tipping elements in the high latitudes all experienced rapid and abrupt change (within 1–2 millennia of each other) across both hemispheres, while recovery to prior conditions took place over multi-millennia. Our synthesis demonstrates important feedback loops between tipping elements, amplifying polar and global change during the Last Interglacial. The high sensitivity and tight interconnections between polar tipping elements suggests that they could exhibit similar thresholds of vulnerability in the future, particularly if the aspirations of the Paris Agreement are not met.
|
|
| 26. |
|
|
| 27. |
|
|
| 28. |
|
|
