935 research outputs found

    Reversal of TGF-β1 stimulation of α-smooth muscle actin and extracellular matrix components by cyclic AMP in Dupuytren's - derived fibroblasts

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Myofibroblasts, a derived subset of fibroblasts especially important in scar formation and wound contraction, have been found at elevated levels in affected Dupuytren's tissues. Transformation of fibroblasts to myofibroblasts is characterized by expression of alpha- smooth muscle actin (α-SMA) and increased production of extracellular matrix (ECM) components, both events of relevance to connective tissue remodeling. We propose that increasing the activation of the cyclic AMP (cAMP)/protein kinase A signaling pathway will inhibit transforming growth factor-beta1 (TGF-β<sub>1</sub>)-induced ECM synthesis and myofibroblast formation and may provide a means to blunt fibrosis.</p> <p>Methods</p> <p>Fibroblasts derived from areas of Dupuytren's contracture cord (DC), from adjacent and phenotypically normal palmar fascia (PF), and from palmar fascia from patients undergoing carpal tunnel release (CTR; CT) were treated with TGF-β<sub>1 </sub>(2 ng/ml) and/or forskolin (10 μM) (a known stimulator of cAMP). Total RNA and protein extracted was subjected to real time RT-PCR and Western blot analysis.</p> <p>Results</p> <p>The basal mRNA expression levels of fibronectin- extra domain A (FN1-EDA), type I (COL1A2) and type III collagen (COL3A1), and connective tissue growth factor (CTGF) were all significantly increased in DC- and in PF-derived cells compared to CT-derived fibroblasts. The TGF-β<sub>1 </sub>stimulation of α-SMA, CTGF, COL1A2 and COL3A1 was greatly inhibited by concomitant treatment with forskolin, especially in DC-derived cells. In contrast, TGF-β<sub>1 </sub>stimulation of FN1-EDA showed similar levels of reduction with the addition of forskolin in all three cell types.</p> <p>Conclusion</p> <p>In sum, increasing cAMP levels show potential to inhibit the formation of myofibroblasts and accumulation of ECM components. Molecular agents that increase cAMP may therefore prove useful in mitigating DC progression or recurrence.</p

    Optimal left ventricular lead position assessed with phase analysis on gated myocardial perfusion SPECT

    Get PDF
    The aim of the current study was to evaluate the relationship between the site of latest mechanical activation as assessed with gated myocardial perfusion SPECT (GMPS), left ventricular (LV) lead position and response to cardiac resynchronization therapy (CRT). The patient population consisted of consecutive patients with advanced heart failure in whom CRT was currently indicated. Before implantation, 2-D echocardiography and GMPS were performed. The echocardiography was performed to assess LV end-systolic volume (LVESV), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). The site of latest mechanical activation was assessed by phase analysis of GMPS studies and related to LV lead position on fluoroscopy. Echocardiography was repeated after 6 months of CRT. CRT response was defined as a decrease of a parts per thousand yen15% in LVESV. Enrolled in the study were 90 patients (72% men, 67 +/- 10 years) with advanced heart failure. In 52 patients (58%), the LV lead was positioned at the site of latest mechanical activation (concordant), and in 38 patients (42%) the LV lead was positioned outside the site of latest mechanical activation (discordant). CRT response was significantly more often documented in patients with a concordant LV lead position than in patients with a discordant LV lead position (79% vs. 26%, p < 0.01). After 6 months, patients with a concordant LV lead position showed significant improvement in LVEF, LVESV and LVEDV (p < 0.05), whereas patients with a discordant LV lead position showed no significant improvement in these variables. Patients with a concordant LV lead position showed significant improvement in LV volumes and LV systolic function, whereas patients with a discordant LV lead position showed no significant improvements.Cardiovascular Aspects of Radiolog

    Queer Touch Between Holy Women: Julian of Norwich, Margery Kempe, Birgitta of Sweden, and the Visitation

    Get PDF
    Under embargo until: 2021-12-17This essay takes a new approach to the well-known meeting between two late-medieval English visionary women, Margery Kempe and the anchoress Julian of Norwich, as described in The Book of Margery Kempe. In this analysis their conversation subtly evokes a long history of women concentrating their subversive power through intimate, spiritual exchange, a history reaching back to the Biblical Visitation scene and expressed in its medieval artistic and literary instantiations. A queer reading illuminates the way that such female same-sex relationships challenge patriarchal systems by offering a privileged access to God outside clerical supervision. By examining Margery and Julian’s encounter, Luke’s Visitation passage, its depiction in a late-medieval Book of Hours, and comparing two different Middle English translations of a Visitation vision in Birgitta of Sweden’s Revelations, the full transgressive effect of queer touch between women—or even its unspoken possibility—emerges.acceptedVersio

    Implementation of seven echocardiographic parameters of myocardial asynchrony to improve the long-term response rate of cardiac resynchronization therapy (CRT)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Cardiac resynchronization Therapy (CRT) is an effective therapy for chronic heart failure with beneficial hemodynamic effects leading to a reduction of morbidity and mortality. The responder rates, however, are low. There are various and contentious echocardiographic parameters of myocardial asynchrony. Patient selection by echocardiographic assessment of asynchrony is thought to improve responder rates.</p> <p>Methods</p> <p>In this small single-center pilot-study, seven established parameters of myocardial asynchrony were used to select patients for CRT: (1) interventricular electromechanical delay (IMD, cut-off ≥ 40 ms), (2) Septal-to-posterior wall motion delay (SPWMD, ≥ 130 ms), (3) maximal difference in time-to-peak velocities between any two of twelve LV segments (Ts-12 ≥ 104 ms), (4) standard deviation of time to peak myocardial velocities (Ts-12-SD, ≥ 34.4 ms), (5) difference between the septal and basal time-to-peak velocity (TDId, ≥ 60 ms), (6) left ventricular electromechanical delay (LVEMD, > 140 ms) and (7) delayed longitudinal contraction (DLC, > 2 segments).</p> <p>16 chronic heart failure patients (NYHA III–IV, LVEF < 0.35, QRS ≥ 120 ms) at least two out of seven parameters of myocardial asynchrony received cardiac resynchronization therapy (CRT-ICD). Follow-up echo examination was after 6 months. The control group was a historic group of CRT patients (n = 38) who had not been screened for echocardiographic signs of myocardial asynchrony prior to device implantation.</p> <p>Results</p> <p>Based on reverse remodeling (relative reduction of LVESV > 15%, relative increase of LVEF > 25%), the responder rate to CRT was 81.2% in patients selected for CRT according to our protocol as compared to 47.4% in the control group (p = 0.04). At baseline, there were on average 4.1 ± 1.6 positive parameters of asynchrony (follow-up: 3.7 [± 1.6] parameters positive, p = 0.52). Only the LVEMD decreased significantly after CRT (p = 0.027). The remaining parameters showed a non-significant trend towards reduction of myocardial asynchrony.</p> <p>Conclusion</p> <p>The implementation of different markers of asynchrony in the selection process for CRT improves the hemodynamic response rate to CRT.</p

    Multi-photon ionisation spectroscopy for rotational state preparation of N+2

    Get PDF
    In this paper we investigate the 2 + 1′ resonance enhanced multi-photon ionisation (REMPI) of molecular nitrogen via the a1Πg(v = 6) intermediate state and analyse its feasibility to generate molecular nitrogen ions in a well defined ro-vibrational state. This is an important tool for high precision experiments based on trapped molecular ions, and is crucial for studying the time variation of the fundamental constant mp/me using N+2. The transition is not reported in the literature and detailed spectral analysis has been conducted to extract the molecular constants of the intermediate state. By carefully choosing the intermediate ro-vibrational state, the ionisation laser wavelength and controlling the excitation laser pulse energy, unwanted formation of rotationally excited molecular ions can be suppressed and ro-vibrational ground state ions can be generated with high purity

    Abnormal expression and processing of the proprotein convertases PC1 and PC2 in human colorectal liver metastases

    Get PDF
    BACKGROUND: The family of proprotein convertases has been recently implicated in tumorigenesis and metastasis in animal models. However, these studies have not yet been completely corroborated in human tumors. METHODS: Using RT PCR, immunoblot and immunohistochemistry we assessed the presence and the processing patterns of the convertases PC1 and PC2 as well as the PC2 specific chaperone 7B2 in human liver metastases originating from colorectal cancer and compared them to unaffected and normal liver. Furthermore, we assessed the presence and processing profiles of PC1, PC2 and 7B2 in primary colon cancers. RESULTS: mRNA, protein expression, and protein cleavage profiles of proprotein convertases 1 and 2 are altered in liver colorectal metastasis, compared to unaffected and normal liver. Active PC1 protein is overexpressed in tumor, correlating with its mRNA profile. Moreover, the enhanced PC2 processing pattern in tumor correlates with the overexpression of its specific binding protein 7B2. These results were corroborated by immunohistochemistry. The specific and uniform convertase pattern observed in the metastases was present only in a fraction of primary colon cancers. CONCLUSION: The uniformly altered proprotein convertase profile in liver metastases is observed only in a fraction of primary colon cancers, suggesting possible selection processes involving PCs during metastasis as well as an active role of PCs in liver metastasis. In addition, the exclusive presence of 7B2 in metastatic tumors may represent a new target for early diagnosis, prognosis and/or treatment

    Assessment of cardiac remodeling in asymptomatic mitral regurgitation for surgery timing: a comparative study of echocardiography and magnetic resonance imaging

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Early surgery is recommended for asymptomatic severe mitral regurgitation (MR), because of increased postoperative left ventricular (LV) dysfunction in patients with late surgery. On the other hand, recent reports emphasized a "watchful waiting" process for the determination of the proper time of mitral valve surgery. In our study, we compared magnetic resonance imaging (MRI) and transthoracic echocardiography to evaluate the LV and left atrial (LA) remodeling; for better definitions of patients that may benefit from early valve surgery.</p> <p>Methods</p> <p>Twenty-one patients with moderate to severe asymptomatic MR were evaluated by echocardiography and MRI. LA and LV ejection fractions (EFs) were calculated by echocardiography and MRI. Pulmonary veins (PVs) were measured from vein orifices in diastole and systole from the tangential of an imaginary circle that completed LA wall. Right upper PV indices were calculated with the formula; (Right upper PV diastolic diameter- Right upper PV systolic diameter)/Right upper PV diastolic diameter.</p> <p>Results</p> <p>In 9 patients there were mismatches between echocardiography and MRI measurements of LV EF. LV EFs were calculated ≥60% by echocardiography, meanwhile < 60% by MRI in these 9 patients. Severity of MR evaluated by effective regurgitant orifice area (EROA) didn't differ with preserved and depressed EFs by MRI (p > 0.05). However, both right upper PV indices (0.16 ± 0.06 vs. 0.24 ± 0.08, p: 0.024) and LA EFs (0.19 ± 0.09 vs. 0.33 ± 0.14, p: 0.025) were significantly decreased in patients with depressed EFs when compared to patients with normal EFs.</p> <p>Conclusions</p> <p>MRI might be preferred when small changes in functional parameters like LV EF, LA EF, and PV index are of clinical importance to disease management like asymptomatic MR patients that we follow up for appropriate surgery timing.</p
    corecore