1,128 research outputs found
Cbx3 inhibits vascular smooth muscle cell proliferation, migration, and neointima formation
This work was supported by British Heart Foundation (FS/09/044/28007, PG/11/40/28891, PG/13/45/30326, PG/15/11/31279, PG/15/86/31723, and PG/16/1/31892 to QX). This work forms part of the research portfolio for the National Institute for Health Research Biomedical Research Centre at Barts
MiRNA-200c-3p promotes endothelial to mesenchymal transition and neointimal hyperplasia in artery bypass grafts
Increasing evidence has suggested a critical role for endothelialâtoâmesenchymal transition (EndoMT) in a variety of pathological conditions. MicroRNAâ200câ3p (miRâ200câ3p) has been implicated in epithelialâtoâmesenchymal transition. However, the functional role of miRâ200câ3p in EndoMT and neointimal hyperplasia in artery bypass grafts remains largely unknown. Here we demonstrated a critical role for miRâ200câ3p in EndoMT. Proteomics and luciferase activity assays revealed that fermitin family member 2 (FERM2) is the functional target of miRâ200câ3p during EndoMT. FERMT2 gene inactivation recapitulates the effect of miRâ200câ3p overexpression on EndoMT, and the inhibitory effect of miRâ200câ3p inhibition on EndoMT was reversed by FERMT2 knockdown. Further mechanistic studies revealed that FERM2 suppresses smooth muscle gene expression by preventing serum response factor nuclear translocation and preventing endothelial mRNA decay by interacting with Yâbox binding protein 1. In a model of aortic grafting using endothelial lineage tracing, we observed that miRâ200câ3p expression was dramatically upâregulated, and that EndoMT contributed to neointimal hyperplasia in grafted arteries. MiRâ200câ3p inhibition in grafted arteries significantly upâregulated FERM2 gene expression, thereby preventing EndoMT and reducing neointimal formation. Importantly, we found a high level of EndoMT in human femoral arteries with atherosclerotic lesions, and that miRâ200câ3p expression was significantly increased, while FERMT2 expression levels were dramatically decreased in diseased human arteries. Collectively, we have documented an unexpected role for miRâ200câ3p in EndoMT and neointimal hyperplasia in grafted arteries. Our findings offer a novel therapeutic opportunity for treating vascular diseases by specifically targeting the miRâ200câ3p/FERM2 regulatory axis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland
Mice with targeted disruptions in the paralogous genes hoxa-3 and hoxd-3 reveal synergistic interactions.
Journal ArticleThe Hox genes encode transcription factors which mediate the formation of the mammalian body plan along the anteroposterior and appendicular axes. Paralogous Hox genes within the separate linkage groups are closely related with respect to DNA sequence and expression, suggesting that they could have at least partially redundant functions. We showed previously that mice homozygous for independent targeted disruptions in the paralogous genes hoxa-3 and hoxd-3 had no defects in common. But our current analysis of double mutants has revealed strong, dosage-dependent interactions between these genes. We report here that in hoxd-3- homozygotes the first cervical vertebra, the atlas, is homeotically transformed to the adjacent anterior structure. Unexpectedly, in double mutants, rather than observing a more extensive homeotic transformation, the entire atlas is deleted. These observations are interpreted in terms of a model in which these Hox genes differentially regulate the proliferation rates of the appropriate sets of precursor cells
The RUSH2A Study: Best-Corrected Visual Acuity, Full-Field Electroretinography Amplitudes, and Full-Field Stimulus Thresholds at Baseline
Purpose: The purpose of this study was to evaluate baseline best corrected visual acuity (BCVA), full-field electroretinography (ERG), full-field stimulus thresholds (FST), and their relationship with baseline demographic and clinical characteristics in the Rate of Progression in Usher syndrome type 2 (USH2A)-related Retinal Degeneration (RUSH2A) multicenter study. Methods: Participants had Usher syndrome type 2 (USH2, N = 80) or autosomal recessive nonsyndromic retinitis pigmentosa (ARRP, N = 47) associated with biallelic variants in the USH2A gene. Associations of demographic and clinical characteristics with BCVA, ERG, and FST were assessed with regression models. Results: In comparison to ARRP, USH2 had worse BCVA (median 79 vs. 82 letters; P < 0.001 adjusted for age), lower rod-mediated ERG b-wave amplitudes (median 0.0 vs. 6.6 ”V; P < 0.001) and 30 Hz flicker cone-mediated ERG amplitudes (median 1.5 vs. 3.1 ”V; P = 0.001), and higher (white, blue, and red) FST thresholds (means [-26, -31, -23 dB] vs. [-39, -45, -28 dB]; P < 0.001 for all stimuli). After adjusting for age, gender, and duration of vision loss, the difference in BCVA between diagnosis groups was attenuated (P = 0.09). Only diagnosis was associated with rod- and cone-mediated ERG parameters, whereas both genders (P = 0.04) and duration of visual loss (P < 0.001) also were associated with FST white stimulus. Conclusions: USH2 participants had worse BCVA, ERG, and FST than ARRP participants. FST was strongly associated with duration of disease; it remains to be determined whether it will be a sensitive measure of progression. Translational Relevance: Using standardized research protocols in RUSH2A, measures have been identified to monitor disease progression and treatment response and differentiate features of prognostic relevance between USH2 and ARRP participants with USH2A mutations
Macrophage-derived MMP-8 determines smooth muscle cell differentiation from adventitia stem/progenitor cells and promotes neointima hyperplasia.
This is a pre-copyedited, author-produced version of an article accepted for publication in Cardiovascular Research following peer review. The version of record Zhou, Y., et al. (2019). "Macrophage-derived MMP-8 determines smooth muscle cell differentiation from adventitia stem/progenitor cells and promotes neointima hyperplasia." is available online at: https://doi.org/10.1093/cvr/cvz044OBJECTIVE: Emerging evidence has suggested that adventitia stem/progenitor cells (AdSPCs) migrate into the intima of arteries in response to injury, where they differentiate toward smooth muscle cells (SMCs) and participate in neointimal hyperplasia. We have previously identified matrix metalloproteinase-8 (MMP8) as a key player in atherogenesis. In this study, we aimed to investigate the functional roles of macrophage-derived MMP8 in AdSPC differentiation and injury-induced arterial remodelling. METHODS AND RESULTS: We first observed an important role for MMP8 in SMC differentiation from embryonic stem cells, but this effect was not seen in AdSPCs. Instead, through macrophages/AdSPCs co-culture and macrophage conditional culture medium studies we have demonstrated that the MMP8 protein secreted from macrophages promotes SMC differentiation from AdSPCs. Mechanistically, we showed that macrophage-derived MMP8 promotes SMC differentiation from AdSPCs through modulating TGF-ÎČ activity and a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10)/Notch1 signaling. We further demonstrated that the binding site for CBF1, Suppressor of Hairless, and Lag-1 (CSL) within SMC gene promoters is responsible for Notch1 mediated SMC differentiation. Finally, we demonstrated that macrophage-derived MMP8 increased injury-induced neointimal SMC hyperplasia by activating ADAM10/Notch1 signaling. CONCLUSIONS: We have identified macrophage-derived MMP8 as a regulator in SMC differentiation from AdSPCs and neointimal SMC hyperplasia in response to injury. Our data provides new insights into the roles of MMP8 in AdSPC differentiation and the pathogenesis of neointima formation in the context of angiographic restenosis, and therefore may aid in the development of novel therapeutic agents for the prevention of this disease.This work was supported by the British Heart Foundation (FS/09/044/28007, PG/11/40/28891, PG/13/45/30326, PG/15/11/31279, PG/15/86/31723, and PG/16/1/31892 to Q.X.); National Natural Science Foundation of China Grant (81800248, 81870206, 91339102, 91639302, 81670397, 81400224, 81570249, 91539103, and 81861128021); Zhejiang Provincial Nature Science Foundation (LD18H020001); and Project of Medical Science Research Foundation from Health Department of Zhejiang Province (2019RC166). F.Y. was supported by China Scholarship Counci
Corneal topographic changes in premenopausal and postmenopausal women
<p>Abstract</p> <p>Background</p> <p>To asses the effect of menopause on the corneal curvature changes using corneal computerized videokeratography (CVK) in premenopausal and postmenopausal healthy women.</p> <p>Methods</p> <p>Thirty-six postmenopausal women with mean ages of 49.2 (range 39 to 57) were enrolled in this randomized, prospective study, comparing with 26 healthy controls with mean ages of 38.5 +/- 4.9 (range 32 to 49). Subjects were determined to be postmenopausal, by the Gynecology and Obstetrics Department, based on blood Follicular Stimulating Hormone (FSH), Luteinizing Hormone (LH), Estradiol, Progesterone levels and clinical complaints. Complete ophthalmic examination and CVK using Haag-Streit System was performed in both premenopausal and postmenopausal women.</p> <p>Results</p> <p>Mean horizontal curvature and vertical curvature of central corneal power in premenopausal women were 43.5 +/- 1.25 Diopter (D), and 44.1 +/- 1.53 D. Mean horizontal curvature and vertical curvature of central corneal power in postmenopausal women were 43.9 +/- 1.4 D, and 44.6 +/- 1.3 D. The mean keratometric astigmatisms of premenopausal and postmenopausal women were 0.81 +/- 0.57 D (4â179 degrees), 0.74 degrees +/- 0.5 D (1â180 degrees) respectively. No significant corneal curvature changes were detected between premenopausal and postmenopausal groups (P > 0.05). On the other hand, we only found negative but significant correlation between horizontal corneal curvature and estrogen level of postmenopausal women (r = -0.346, p = 0.038).</p> <p>Conclusion</p> <p>Menopause is physiologic process and may also affect corneal topographic changes. In postmenopausal women, corneal steeping was observed minimally compared to premenopausal women. The results suggest that changes in estrogen level of women with menopause are associated with slightly alteration of horizontal curvature of cornea.</p
Observational and Physical Classification of Supernovae
This chapter describes the current classification scheme of supernovae (SNe).
This scheme has evolved over many decades and now includes numerous SN Types
and sub-types. Many of these are universally recognized, while there are
controversies regarding the definitions, membership and even the names of some
sub-classes; we will try to review here the commonly-used nomenclature, noting
the main variants when possible. SN Types are defined according to
observational properties; mostly visible-light spectra near maximum light, as
well as according to their photometric properties. However, a long-term goal of
SN classification is to associate observationally-defined classes with specific
physical explosive phenomena. We show here that this aspiration is now finally
coming to fruition, and we establish the SN classification scheme upon direct
observational evidence connecting SN groups with specific progenitor stars.
Observationally, the broad class of Type II SNe contains objects showing strong
spectroscopic signatures of hydrogen, while objects lacking such signatures are
of Type I, which is further divided to numerous subclasses. Recently a class of
super-luminous SNe (SLSNe, typically 10 times more luminous than standard
events) has been identified, and it is discussed. We end this chapter by
briefly describing a proposed alternative classification scheme that is
inspired by the stellar classification system. This system presents our
emerging physical understanding of SN explosions, while clearly separating
robust observational properties from physical inferences that can be debated.
This new system is quantitative, and naturally deals with events distributed
along a continuum, rather than being strictly divided into discrete classes.
Thus, it may be more suitable to the coming era where SN numbers will quickly
expand from a few thousands to millions of events.Comment: Extended final draft of a chapter in the "SN Handbook". Comments most
welcom
Randomized trial to compare the efficacy and toxicity of cyclophosphamide, methotrexate and 5-fluorouracil (CMF) with methotrexate mitoxantrone (MM) in advanced carcinoma of the breast
One hundred and sixteen patients with locally advanced or metastatic breast cancer were randomized to receive CMF (cyclophosphamide 600 mg mâ2 day 1 and 8 i.v., 5-fluorouracil 600 mg mâ2 day 1 and 8 i.v.,, methotrexate 40 mg mâ2 day 1 and 8 i.v., monthly for 6 cycles) or MM (methotrexate 30 mg mâ2, mitoxantrone 6.5 mg mâ2, both i.v. day 1 3-weekly for 8 cycles) as first line treatment with chemotherapy. Objective responses occurred in 17 patients out of 58 (29%) who received CMF and nine out of 58 (15%) who received MM; 95% confidence interval for difference in response rates (â1%â29%), P = 0.07. No statistically significant differences were seen in overall survival or time to progression between the two regimes although a tendency towards a shorter progression time on the MM regime must be acknowledged. There was, however, significantly reduced haematological toxicity (P < 0.001) and alopecia (P < 0.001) and fewer dose reductions and delays in patients randomized to MM. No statistically significant differences were seen between the two regimes in terms of quality of life (QOL). However, some association between QOL and toxicity was apparent overall with pooled QOL estimates tending to indicate a worsening in psychological state with increasing maximum toxicity over treatment. Despite the fact that results surrounding response rates and time to progression did not reach statistical significance, their possible compatibility with an improved outcome on CMF treatment must be borne in mind. However, MM is a well-tolerated regimen with fewer side-effects than CMF, which with careful patient management and follow-up, therefore, may merit consideration as a first-line treatment to palliate patients with metastatic breast cancer who are infirm or elderly. © 1999 Cancer Research Campaig
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