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61.
Scott T. Chiesa Marietta Charakida Georgios Georgiopoulos Frida Dangardt Kaitlin H. Wade Alicja Rapala Devina J. Bhowruth Helen C. Nguyen Vivek Muthurangu Rukshana Shroff George Davey Smith Debbie A. Lawlor Naveed Sattar Nicholas J. Timpson Alun D. Hughes John E. Deanfield 《JACC: Cardiovascular Imaging》2021,14(2):468-478
ObjectivesThis study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.BackgroundGreater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.MethodsAssociations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.ResultsFat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: ?0.0032; 95% CI: 0.004 to ?0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor?associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.ConclusionsSubtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood. 相似文献
62.
Stephen H. Little Vinayak Bapat Philipp Blanke Mayra Guerrero Vivek Rajagopal Robert Siegel 《JACC: Cardiovascular Imaging》2021,14(1):22-40
Catheter-based interventions to improve mitral valve function are dependent on anatomic and functional information provided by noninvasive imaging to plan, perform, and evaluate each intervention. In this review we highlight the importance of imaging guidance for catheter-based interventions on prosthetic mitral valves, surgical rings, and native valve annular calcification. Both repair and replacement procedures are discussed. We review the general features common to this collection of procedures and discuss specific imaging issues and concerns for each procedure. Figures and intraprocedural videos emphasize central messages using case examples. 相似文献
63.
Epicardial RFA to Achieve Electrical PV Isolation. During catheter ablation of atrial fibrillation, ablation within the pulmonary veins is undesirable due to the risk of pulmonary venous stenosis and the possibility of leaving residual cuffs of arrhythmogenic tissue proximal to the ablation lesion set. An extra-ostial pulmonary vein isolation strategy may circumvent these limitations, but achieving electrical isolation can be technically challenging, even with the use of saline-irrigated radiofrequency energy technology. This report describes the successful use of epicardial radiofrequency ablation in a patient in whom endocardial irrigated radiofrequency ablation failed to achieve extra-ostial pulmonary vein isolation. 相似文献
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65.
Alok Kumar Singh Vivek Singh Mahendra Pal Singh Pratima Shrivastava Nisha Singh Indrajeet Singh Gambhir 《Immunopharmacology and immunotoxicology》2013,35(2):411-423
It is well established that the immune potential declines with age. However, there is a great paucity of information regarding role of monocytes in elderly suffering from cerebrovascular accident. This present study was undertaken to investigate if the functions of peripheral blood mononuclear cells have any correlation to the manifestation of an age-associated cerebrovascular disorders: myocardial infraction, cerebrovascular (infract & hemorrhage). An age-associated inhibition in the production of interleukin-1 (IL-1) by monocytes was observed while the production of nitric oxide (NO) remained unaltered in the response of monocytes, obtained from normal elderly donors, to Lipopolysaccharide (LPS) treatment in vitro. Cerebrovascular pathologies were found to be associated with an augmentation of IL-1 production by monocyte, while NO production was augmented in case of CVA (hemorrhage) and MI. Trace element copper was found to be lower in the serum of patients suffering from CVA, while concentration of zinc was found to be elevated in serum compared to these trace elements in normal adults. Thus these factors are likely to play a role in the pathogenesis of age-related cerebrovascular disorders. 相似文献
66.
67.
The rapid pace at which COVID-19 studies are being published is surpassed only by the spread of the virus and the destruction wreaked by the pandemic globally. Therefore, it is likely that, even in the few months prior to this article reaching print, the COVID-19 literature would have moved on. The authors of this article work at a centre for COVID autopsies in London, and the aim of the article is, using their first-hand experience of COVID-19 autopsies, to distil what in their judgement are the most valid and important findings of internationally published COVID-19 autopsy studies. The intention is to provide an illustrated summary of the pathology of the organ systems most often affected by COVID-19, which will be particularly useful to trainee histopathologists and to busy consultant surgical histopathologists who may not have encountered COVID-19 first hand. For the reader who wishes to probe further the question of pathogenesis, a few pertinent references are provided. 相似文献
68.
Cynthia Scott Karthik Ramakrishnan Narayanan Vivek Chandran Saravanan Gurram Prashanthi 《Journal of oral and maxillofacial surgery》2021,79(6):1330.e1-1330.e12
69.
Karthik Ramakrishnan Cynthia Scott Pavithra Sarda. K Narayanan Vivek Chandran Saravanan 《Journal of cranio-maxillo-facial surgery》2021,49(6):488-493
This retrospective study aims to evaluate the correlation between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture using computed tomography.Medical records of patients diagnosed with unilateral condylar fractures from the year 2012–2019 were reviewed. The shape of the condylar head on the non - fractured side was analysed using a Radiant Dicom Viewer. The analysis was done using both visual and analytical methods. In the analytical method, a horizontal line was drawn at the base of the curvature of the condylar head. The highest peak point of the head was marked, and a perpendicular line was drawn connecting the highest point to the horizontal line. The shape was categorized into four types as convex, flat, angled, and round based on these lines.201 CT scans were examined, of which 69 were excluded as they did not meet the inclusion criteria. The remaining 132 were included in our study. On examining the shape, flat-shaped condyle was seen in 57 scans (43.2%), followed by convex in 31 scans (23.4%), angled in 30 (22.7%) and round in 14 scans (10.6%). The relationship between the shape of the mandibular condylar head and the incidence of unilateral condylar fracture was analysed using a chi-square test, which showed high statistical significance (p value 0.0001). The flat-shaped condylar head was more prone to fracture, and the round-shaped condylar head was least prone to fracture.In conclusion, the shape of the mandibular condylar head had a statistically significant association with the incidence of unilateral condylar fracture. The assessment of the shape of the condylar head can be taken as a guide to suspect condylar fractures and other associated mandibular fractures. 相似文献