38 research outputs found
Resident phenotypically modulated vascular smooth muscle cells in healthy human arteries.
Vascular interstitial cells (VICs) are non-contractile cells with filopodia previously described in healthy blood vessels of rodents and their function remains unknown. The objective of this study was to identify VICs in human arteries and to ascertain their role. VICs were identified in the wall of human gastro-omental arteries using transmission electron microscopy. Isolated VICs showed ability to form new and elongate existing filopodia and actively change body shape. Most importantly sprouting VICs were also observed in cell dispersal. RT-PCR performed on separately collected contractile vascular smooth muscle cells (VSMCs) and VICs showed that both cell types expressed the gene for smooth muscle myosin heavy chain (SM-MHC). Immunofluorescent labelling showed that both VSMCs and VICs had similar fluorescence for SM-MHC and αSM-actin, VICs, however, had significantly lower fluorescence for smoothelin, myosin light chain kinase, h-calponin and SM22α. It was also found that VICs do not have cytoskeleton as rigid as in contractile VSMCs. VICs express number of VSMC-specific proteins and display features of phenotypically modulated VSMCs with increased migratory abilities. VICs, therefore represent resident phenotypically modulated VSMCs that are present in human arteries under normal physiological conditions
Ultrashort time-to-echo MRI of the cartilagenous endplate and relationship to degenerative disc disease and schmorl's nodes
Session - The Short of ItINTRODUCTION: The vertebral endplate is composed of an inner bony and outer cartilaginous endplates (CEP). The CEP supplies the intervertebral disc (IVD) with nutrients and metabolites, and is instrumental for metabolism, exchange of waste products and biomechanics of the disc 1. Lumbar disc degeneration on MRI is a risk factor for the development of low back pain 2. It has been previously hypothesized that changes in disc mechanics may be initiated by damage to the endplate 3, 4. Similarly, CEP defects may be involved in the formation of Schmorl’s nodes (SNs) (i.e. invagination of IVD material into the adjacent endplates) 5, which associated with severity of lumbar disc degeneration 6. The ultrashort time-to-echo (UTE) MRI is an imaging technique that enables improved visualization of tissues with short T2 relaxation that appear dark in signal on conventional T2-weighted (T2W) imaging. By employing this technique in the lumbar spine, we believe that the CEP, which appears hypointense in T2W MRI, may be observed as continuous high-signal and may thus be differentiated from the bony endplate. Although cadaveric studies have addressed the feasibility of UTE in assessing the CEP 7, studies addressing such technology in live human subjects …published_or_final_versionThe 19th Annual Meeting and Exhibition of the International Society for Magnetic Resonance in Medicine (ISMRM 2011), Montreal, QC., 7-13 May 2011. In Proceedings of the 19th ISMRM, 2011, v. 19, p. 57
Ultrashort time-to-echo MRI of the cartilagenous endplate & relationship to degenerative disc disease & Schmorl’s nodes
Session - The Short of It: no. 570Early diagnosis of CEP defects by UTE technique may provide useful information for understanding the pathogenesis of each of DDD and Schmorl¡¦s nodes (SN). The objective of this study was to assess CEP integrity in normal IVD levels, levels with degenerated IVDs and levels with SNs. Based on the UTE images, CEP defects were defined as discontinuity of high signal over 4 consecutive slices. Results showed that CEP defects were found to have a 4.5 fold increased likelihood of having DDD. No association between CEP defects and SNs was established. The effects of age and CEP defects were found to be level dependent. (abstract by publisher)postprin
Assessment of the neurocentral synchondrosis in pediatric spines and the "developmental" etiology of Schmorl's nodes
Special Poster: no. SP13INTRODUCTION: Schmorl's nodes of the thoraco-lumbar region have been associated with the presence and severity of disc degeneration in adults. The etiology of Schmorl's nodes remains precarious; however a unique multilevel phenotype of 'kissing' nodes seems to suggest a developmental origin. The neurocentral synchondrosis (NCS) are cartilaginous growth plates near the neural arch ossification centres in a growing vertebrae that may play a direct role in the development of endplate abnormalities, such as Schmorl's nodes. This study assessed the NCS in ...postprin
Adverse Drug Reactions Related Hospital Admissions in Persons Aged 60 Years and over, The Netherlands, 1981–2007: Less Rapid Increase, Different Drugs
Background: Epidemiologic information on time trends of Adverse Drug Reactions (ADR) and ADR-related hospitalizations is scarce. Over time, pharmacotherapy has become increasingly complex. Because of raised awareness of ADR, a decrease in ADR might be expected. The aim of this study was to determine trends in ADR-related hospitalizations in the older Dutch population. Methodology and Principal Findings: Secular trend analysis of ADR-related hospital admissions in patients ≥60 years between 1981 and 2007, using the National Hospital Discharge Registry of the Netherlands. Numbers, age-specific and age-adjusted incidence rates (per 10,000 persons) of ADR-related hospital admissions were used as outcome measures in each year of the study. Between 1981 and 2007, ADR-related hospital admissions in persons ≥60 years increased by 143%. The overall standardized incidence rate increased from 23.3 to 38.3 per 10,000 older persons. The increase was larger in males than in females. Since 1997, the increase in incidence rates of ADR-related hospitalizations flattened (percentage annual change 0.65%), compared to the period 1981-1996 (percentage annual change 2.56%). Conclusion/Significance: ADR-related hospital admissions in older persons have shown a rapidly increasing trend in the Netherlands over the last three decades with a temporization since 1997. Although an encouraging flattening in the increasing trend of ADR-related admissions was found around 1997, the incidence is still rising, which warrants sustained attention to this problem
Anti-human platelet antigen (HPA)-1a antibodies may affect trophoblast functions crucial for placental development: a laboratory study using an in vitro model
Ultrashort time-to-echo MRI of the cartilaginous endplate: technique and association with intervertebral disc degeneration
Conference Theme: From Degeneration to PainThis free journal suppl. contain congress abstracts of WSR 2012INTRODUCTION: An association between cartilaginous endplate (CEP) defects and intervertebral disk (IVD) degeneration has been previously suggested in animal and cadaveric studies. There have been no previous reports in the literature that describe the use of ultrashort time-to-echo (UTE) magnetic resonance imaging (MRI) to assess the CEP in humans in vivo. As such, the purpose of this study was to report the feasibility of the UTE MRI technique to assess CEP defects in humans in vivo using and to assess their relationship with IVD degeneration. MATERIALS AND METHODS: Nine volunteer subjects (mean age 43.9 years; range: 22 to 61 years) were recruited, representing 54 IVDs and 108 CEPs. The subjects underwent T2-weighted and UTE MRI to assess for the presence and severity of IVD degeneration, and for the presence of CEP defects, respectively, from T12 to S1. Intervertebral disk degeneration was graded according to the Schneiderman et al classification on T2-weighted MRI. CEP defects were defined on UTE MRI as discontinuity of high-signal over 4 consecutive images and were independently assessed by two observers. RESULTS: Total 37% out of 108 (34.3%) CEPs had defects, which mainly occurred at T12/L1, L1/L2, and L4/L5 (p = 0.008). Multivariate logistic regression revealed that lower BMI (p = 0.009) and younger (p = 0.034) individuals had a decreased likelihood of having CEP defects. A statistically significant association was found to exist between the presence of CEP defects and IVD degeneration (p = 0.036).A higher prevalence of degenerated IVDs with CEP defects were found at L4/5 and L5/S1, while degenerated IVDs with no CEP defects were found throughout the whole lumbar region. Mean IVD degeneration scores of the L4/5 and L5/S1 levels with CEP defects were higher in comparison to those with no CEP defects. CONCLUSION: Our study demonstrates the feasibility of using UTE MRI in humans in vivo to assess the integrity of the CEP. A statistically significant association was found to exist between the presence of CEP defects and IVD degeneration. In the lower lumbar region, more severe degeneration was found to occur in the IVDs with CEP defects than in those without defects. Such imaging technology may broaden the understanding of IVD degeneration and facilitate management options that target IVD repair/regeneration.link_to_OA_fulltex
Ultrashort time-to-echo MRI of human intervertebral disc endplate: a feasibility study
The 18th Annual Scientific Meeting of Hong Kong College of Radiologists, Hong Kong, 30-31 October 2010
Home blood pressure monitoring with nurse-led telephone support among patients with hypertension and a history of stroke: a community-based randomized controlled trial
BACKGROUND: Adequate control of blood pressure reduces the risk of recurrent stroke. We conducted a randomized controlled study to determine whether home blood pressure monitoring with nurse-led telephone support would reduce blood pressure in patients with hypertension and a history of stroke. METHODS: We recruited 381 participants (mean age 72 years) from outpatient and inpatient stroke clinics between Mar. 1, 2007, and Aug. 31, 2009. Nearly half (45%, 170) of the participants had some disability due to stroke. Participants were visited at home for a baseline assessment and randomly allocated to home blood pressure monitoring (n = 187) or usual care (n = 194). Those in the intervention group were given a monitor, brief training and telephone support. Participants who had home blood pressure readings consistently over target (target < 130/80 mm Hg) were advised to consult their family physician. The main outcome measure was a fall in systolic blood pressure after 12 months, measured by an independent researcher unaware of group allocation. RESULTS: Despite more patients in the intervention group than in the control group having changes to antihypertensive treatment during the trial period (60.1% [98/163] v. 47.6% [78/164], p = 0.02), the fall in systolic blood pressure from baseline did not differ significantly between the groups (adjusted mean difference 0.3 mm Hg, 95% confidence interval –3.6 to 4.2 mm Hg). Subgroup analysis showed significant interaction with disability due to stroke (p = 0.03 at 6 months) and baseline blood pressure (p = 0.03 at 12 months). INTERPRETATION: Overall, home monitoring did not improve blood pressure control in patients with hypertension and a history of stroke. It was associated with a fall in systolic pressure in patients who had uncontrolled blood pressure at baseline and those without disability due to stroke. Trial registration: ClinicalTrials.gov registration NCT0051480