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Sample records for allograft vasculopathy cav

  1. Predicting the development of cardiac allograft vasculopathy.

    PubMed

    Seki, Atsuko; Fishbein, Michael C

    2014-01-01

    Cardiac transplantation is a lifesaving therapy for patients with end-stage cardiovascular disease. There has been remarkable progress in controlling acute rejection, and the early survival rate after the heart transplantation has significantly improved. Cardiac allograft vasculopathy (CAV) is one of the common causes of death and a major limiting factor for long-term graft survival years after heart transplantation. CAV is a progressive occlusion of arteries and veins of the transplanted heart. CAV is often clinically silent because of the denervation of the transplanted heart. CAV tends to be found at an advanced stage of disease, including myocardial infarction (MI), congestive heart failure, arrhythmia, and/or sudden cardiac death. Because of the serious sequelae of CAV, risk factors, prevention, and prediction of CAV have been investigated. Despite the effort by many researchers, the pathogenesis is not yet completely understood. There are a number of both immune and nonimmune factors in the donor and recipient that are related to the development of CAV. In addition, several biomarkers in blood and tissue are found to correlate with the presence of CAV, and that may be able to predict CAV. Here, we review the pathology, pathogenesis, risk factors, diagnosis, and the potential for prediction of CAV.

  2. The recipient's heme oxygenase-1 promoter region polymorphism is associated with cardiac allograft vasculopathy.

    PubMed

    Freystaetter, Kathrin; Andreas, Martin; Bilban, Martin; Perkmann, Thomas; Kaider, Alexandra; Masetti, Marco; Kocher, Alfred; Wolzt, Michael; Zuckermann, Andreas

    2017-02-10

    Heme oxygenase-1 (HO-1) catalyses the degradation of heme to biliverdin, free iron, and carbon monoxide. The promoter region contains a highly polymorphic (GT)n repeat, where shorter (GT)n repeat sequences are linked to higher transcriptional activity, which was shown to correlate with a cytoprotective effect. Higher HO-1 levels may protect from cardiac allograft vasculopathy. Cardiac allograft recipients transplanted between 1988 and 2012 were analyzed for the HO-1 (GT)n repeat polymorphism using PCR and DNA fragment analysis with capillary electrophoresis. A relation to cardiac allograft vasculopathy (CAV) was analyzed using Cox regression including common risk factors for CAV and the occurrence of rejection episodes as explanatory variables. A total of 344 patients were analyzed, of which 127 patients were positive for CAV (36.9%). In our multivariable Cox regression analysis, the short homozygous HO-1 (GT)n genotype with <27 repeats (S/S) revealed a higher risk for CAV (P = 0.032). Donor age (P = 0.001) and donor weight (P = 0.005) were significant predictors for CAV. A potential risk for CAV was associated with rejection episodes (P = 0.058) and history of smoking (P = 0.06). The recipient HO-1 (GT)n genotype may contribute to CAV development. This finding has to be evaluated in larger series including studies targeting the underlying disease mechanism.

  3. Allograft vasculopathy after allogeneic vascularized knee transplantation.

    PubMed

    Diefenbeck, Michael; Nerlich, Andreas; Schneeberger, Stefan; Wagner, Frithjof; Hofmann, Gunther O

    2011-01-01

    Composite tissue allotransplantation represents a new discipline in reconstructive surgery. Over the past 10 years, we have performed six human vascularized allogeneic knee transplantations. All of these grafts have been lost within the first 56 months. A histomorphologic assessment of the latest case resulted in the detection of diffuse concentric fibrous intimal thickening and occlusion of graft vessels. Findings are comparable with cardiac allograft vasculopathy. The lack of adequate tools for monitoring graft rejection might have allowed multiple untreated episodes of acute rejection, triggering myointimal proliferation and occlusion of graft vessels. Graft vasculopathy represents an obstacle to long-term vascularized bone and joint allograft survival, and adequate tools for monitoring need to be developed.

  4. Qualitative Perfusion Cardiac Magnetic Resonance Imaging Lacks Sensitivity in Detecting Cardiac Allograft Vasculopathy

    PubMed Central

    Colvin-Adams, Monica; Petros, Salam; Raveendran, Ganesh; Missov, Emil; Medina, Eduardo; Wilson, Robert

    2011-01-01

    Background Cardiac allograft vasculopathy (CAV) is a major complication after heart transplantation, requiring frequent surveillance angiography. Though cardiac angiography is the gold standard, it is insensitive in detecting transplant vasculopathy and invasive. Perfusion MRI provides a noninvasive alternative and possibly a useful modality for studying CAV. We sought to compare the accuracy of qualitative perfusion MRI to coronary angiography in detecting CAV. Methods A retrospective analysis was performed in 68 heart transplant recipients who had simultaneous surveillance cardiac MRI and coronary angiogram and who underwent transplantation between 2000 and 2007. We compared results of qualitative MRI to those of the cardiac angiogram. Sensitivity and specificity of MR were calculated. Results Sixty-eight patients underwent both cardiac MRI and coronary angiogram. 73.5% were male; mean age was 45.37 ± 14 years. Mean duration of heart transplantation was 7.9 ± 5.2 years. The mean ejection fraction was 55% in the patients without CAV and 57.4% in those with CAV. There were 48 normal and 24 abnormal MRI studies. The overall sensitivity was 41% and specificity was 74%. Conclusions Qualitative assessment of perfusion cardiac MR has low sensitivity and moderate specificity for detecting CAV. The sensitivity of MRI was slightly improved with severity of disease.

  5. The Role of MIG/CXCL9 in Cardiac Allograft Vasculopathy

    PubMed Central

    Yun, James J.; Fischbein, Michael P.; Whiting, David; Irie, Yoshihito; Fishbein, Michael C.; Burdick, Marie D.; Belperio, John; Strieter, Robert M.; Laks, Hillel; Berliner, Judith A.; Ardehali, Abbas

    2002-01-01

    T lymphocytes play a critical role in chronic rejection of transplanted hearts, or cardiac allograft vasculopathy (CAV). However, the molecular mediators of T lymphocyte recruitment in CAV are incompletely defined. We hypothesized that the chemokine, monokine induced by interferon-γ (MIG/CXCL9), which induces T lymphocyte migration in vitro, participates in T lymphocyte recruitment in CAV. In a previously characterized MHC II-mismatched murine model of CAV, intragraft MIG/CXCL9 gene transcript and protein levels increased on days 7, 14, and 24 days after transplantation, paralleling T lymphocyte recruitment and preceding intimal thickening. Antibody neutralization of MIG/CXCL9 significantly reduced CD4+ T lymphocyte infiltration and intimal thickening in this model. MIG/CXCL9 was produced by graft-infiltrating MOMA-2+ macrophages in early and late stages of CAV. And, although T lymphocytes did not produce MIG/CXCL9, recipient CD4+ T lymphocytes were required for sustained intragraft MIG/CXCL9 production and CAV development. These findings demonstrate that 1) MIG/CXCL9 plays an important role in CD4+ T lymphocyte recruitment and development of CAV, 2) MOMA-2+ macrophages are the predominant recipient-derived source of MIG/CXCL9, and 3) recipient CD4 lymphocytes are necessary for sustained MIG/CXCL9 production and CAV development in this model. Neutralization of the chemokine MIG/CXCL9 may have therapeutic potential for the treatment of chronic rejection after heart transplantation. PMID:12368204

  6. Optical coherence tomography and highly sensitivity troponin T for evaluating cardiac allograft vasculopathy.

    PubMed

    Garrido, Iris P; García-Lara, Juan; Pinar, Eduardo; Pastor-Pérez, Francisco; Sánchez-Mas, Jesus; Valdés-Chavarri, Mariano; Pascual-Figal, Domingo A

    2012-09-01

    Cardiac allograft vasculopathy (CAV) is a major impediment to long-term graft survival after heart transplantation. Intravascular ultrasound (IVUS) is more sensitive than coronary angiography for diagnosis, but the identification of specific plaque components or plaque composition is limited. In addition, there is an evident need for other noninvasive tools for diagnosing CAV. The aim of this study was to assess the utility of 2 new techniques for evaluating CAV: optical coherence tomography (OCT), and new high-sensitivity troponin T (hsTnT) assays. In 21 heart transplantation patients, coronary arteriography with IVUS and OCT were performed. Maximal intimal thickness (MIT) and luminal area at the most severe site were measured using the 2 techniques. Immediately before cardiac catheterization, blood samples were obtained and hsTnT levels measured. The evaluation of CAV by OCT showed a good correlation with IVUS measurements, with a mean difference in MIT of 0.0033 (95% confidence interval -0.049 to 0.043), taking advantage of lower interobserver variability (r = 0.94 for OCT vs r = 0.78 for IVUS) and better plaque characterization. When independent predictors of MIT were assessed in a multiple linear regression model, time after transplantation (β = 0.488, p = 0.004) and hsTnT (β = 0.392, p = 0.011) were the only independent predictors of MIT (R(2) = 0.591). In conclusion, this study is the first to evaluate 2 new techniques, OCT and hsTnT, in the challenging setting of CAV. The findings suggest that OCT provides lower interobserver variability and better plaque characterization than IVUS. Also, hsTnT could become a useful tool for ruling out CAV.

  7. Viral Infection Induces De Novo Lesions of Coronary Allograft Vasculopathy through a Natural Killer Cell-Dependent Pathway

    PubMed Central

    Graham, Jay A.; Wilkinson, Robert A.; Hirohashi, Tsutomu; Chase, Catharine M.; Colvin, Robert B.; Madsen, Joren C.; Fishman, Jay A.; Russell, Paul S.

    2009-01-01

    Viral infections including those due to cytomegalovirus (CMV) have been associated with accelerated cardiac allograft vasculopathy (CAV) in clinical trials and some animal models. Evidence demonstrating a direct causal relationship between such infections and de novo formation of coronary vascular lesions is lacking. Heterotopic murine cardiac transplants were performed in a parental to F1 combination in animals lacking both T- and B-lymphocytes (RAG−/−). Coronary vasculopathy developed almost exclusively in the presence of recipient infection with lymphocytic choriomeningitis virus (LCMV) but not in uninfected controls. This process was also dependent upon the presence of NK cells as depletion of NK cells abrogated the process. These data show that a viral infection in its native host, and not previously implicated in the production of CAV, can contribute to the development of advanced coronary vascular lesions in cardiac allotransplants in mice. These data also suggest that virus-induced CAV can develop via an NK-cell dependent pathway in the absence of T- and B-lymphocytes. PMID:19843029

  8. Bidirectional ventricular tachycardia due to coronary allograft vasculopathy a unique presentation.

    PubMed

    Bhavnani, Sanjeev P; Clyne, Christopher A

    2012-10-01

    Bidirectional ventricular tachycardia (BVT) is an uncommon type of polymorphic ventricular tachycardia (PVT) with alternating polarity of the QRS complex most commonly described digitalis toxicity. Recent data has demonstrated the possible molecular basis of this electrocardiographic phenomenon. To our knowledge this is the first reported case of BVT in a patient with orthotopic cardiac transplantation and coronary allograft vasculopathy.

  9. International Society for Heart and Lung Transplantation working formulation of a standardized nomenclature for cardiac allograft vasculopathy-2010.

    PubMed

    Mehra, Mandeep R; Crespo-Leiro, Maria G; Dipchand, Anne; Ensminger, Stephan M; Hiemann, Nicola E; Kobashigawa, Jon A; Madsen, Joren; Parameshwar, Jayan; Starling, Randall C; Uber, Patricia A

    2010-07-01

    The development of cardiac allograft vasculopathy remains the Achilles heel of cardiac transplantation. Unfortunately, the definitions of cardiac allograft vasculopathy are diverse, and there are no uniform international standards for the nomenclature of this entity. This consensus document, commissioned by the International Society of Heart and Lung Transplantation Board, is based on best evidence and clinical consensus derived from critical analysis of available information pertaining to angiography, intravascular ultrasound imaging, microvascular function, cardiac allograft histology, circulating immune markers, non-invasive imaging tests, and gene-based and protein-based biomarkers. This document represents a working formulation for an international nomenclature of cardiac allograft vasculopathy, similar to the development of the system for adjudication of cardiac allograft rejection by histology.

  10. SDF-1/CXCR4/CXCR7 is pivotal for vascular smooth muscle cell proliferation and chronic allograft vasculopathy.

    PubMed

    Thomas, Michael N; Kalnins, Aivars; Andrassy, Martin; Wagner, Anne; Klussmann, Sven; Rentsch, Markus; Habicht, Antje; Pratschke, Sebastian; Stangl, Manfred; Bazhin, Alexandr V; Meiser, Bruno; Fischereder, Michael; Werner, Jens; Guba, Markus; Andrassy, Joachim

    2015-12-01

    Chronic rejection remains a major obstacle in transplant medicine. Recent studies suggest a crucial role of the chemokine SDF-1 on neointima formation after injury. Here, we investigate the potential therapeutic effect of inhibiting the SDF-1/CXCR4/CXCR7 axis with an anti-SDF-1 Spiegelmer (NOX-A12) on the development of chronic allograft vasculopathy. Heterotopic heart transplants from H-2bm12 to B6 mice and aortic transplants from Balb/c to B6 were performed. Mice were treated with NOX-A12. Control animals received a nonfunctional Spiegelmer (revNOX-A12). Samples were retrieved at different time points and analysed by histology, RT-PCR and proliferation assay. Blockade of SDF-1 caused a significant decrease in neointima formation as measured by intima/media ratio (1.0 ± 0.1 vs. 1.8 ± 0.1, P < 0.001 AoTx; 0.35 ± 0.05 vs. 1.13 ± 0.27, P < 0.05 HTx). In vitro treatment of primary vascular smooth muscle cells with NOX-A12 showed a significant reduction in proliferation (0.42 ± 0.04 vs. 0.24 ± 0.03, P < 0.05). TGF-β, TNF-α and IL-6 levels were significantly reduced under SDF-1 inhibition (3.42 ± 0.37 vs. 1.67 ± 0.33, P < 0.05; 2.18 ± 0.37 vs. 1.0 ± 0.39, P < 0.05; 2.18 ± 0.26 vs. 1.6 ± 0.1, P < 0.05). SDF-1/CXCR4/CXCR7 plays a critical role in the development of chronic allograft vasculopathy (CAV). Therefore, pharmacological inhibition of SDF-1 with NOX-A12 may represent a therapeutic option to ameliorate chronic rejection changes.

  11. Sex Related Differences in the Risk of Antibody-Mediated Rejection and Subsequent Allograft Vasculopathy Post-Heart Transplantation: A Single-Center Experience

    PubMed Central

    Grupper, Avishay; Nestorovic, Emilija M.; Daly, Richard C.; Milic, Natasa M.; Joyce, Lyle D.; Stulak, John M.; Joyce, David L.; Edwards, Brooks S.; Pereira, Naveen L.; Kushwaha, Sudhir S.

    2016-01-01

    Background Pregnancies may result in antibodies against HLA, a risk factor for antibody-mediated rejection (AMR) and subsequent cardiac allograft vasculopathy (CAV) after heart transplantation (HTx). The aim of this study was to evaluate sex differences in the incidence of AMR events and subsequent risk of CAV among HTx recipients. Methods The study comprised 160 patients (51 [32%] women) who underwent HTx in 2008 to 2014. The cumulative effect of AMR events was calculated by AMR score (sum of myocardial biopsy grading divided by number of biopsies taken during 3 years post-HTx). Results Females had higher levels of anti-HLA I antibodies pre-HTx compared to males which was associated with a history of pregnancies, total number of children and with a higher AMR score at 6 months post-HTx (P < 0.05). Women demonstrated a significant increase in the total incidence of AMR events (27 vs. 7%, P = 0.001) and in AMR scores at 6, 12, 24 and 36 months post-HTx compared to men (P < 0.05). There were no differences in cellular rejection between the groups. A history of AMR events was associated with a significantly increased risk of severe CAV onset (hazard ratio, 7.0; 95% confidence interval, 1.5-31.5; P = 0.012). Conclusions Women are at higher risk for AMR post-HTx which subsequently increases their risk for CAV. Females recipients may benefit from closer surveillance to identify AMR at an earlier stage post-HTx, and targeted immunosuppressive therapy to attenuate the development of CAV. PMID:27795988

  12. Late Failing Heart Allografts: Pathology of Cardiac Allograft Vasculopathy and Association With Antibody-Mediated Rejection.

    PubMed

    Loupy, A; Toquet, C; Rouvier, P; Beuscart, T; Bories, M C; Varnous, S; Guillemain, R; Pattier, S; Suberbielle, C; Leprince, P; Lefaucheur, C; Jouven, X; Bruneval, P; Duong Van Huyen, J P

    2016-01-01

    In heart transplantation, there is a lack of robust evidence of the specific causes of late allograft failure. We hypothesized that a substantial fraction of failing heart allografts may be associated with antibody-mediated injury and immune-mediated coronary arteriosclerosis. We included all patients undergoing a retransplantation for late terminal heart allograft failure in three referral centers. We performed an integrative strategy of heart allograft phenotyping by assessing the heart vascular tree including histopathology and immunohistochemistry together with circulating donor-specific antibodies. The main analysis included 40 explanted heart allografts patients and 402 endomyocardial biopsies performed before allograft loss. Overall, antibody-mediated rejection was observed in 19 (47.5%) failing heart allografts including 16 patients (40%) in whom unrecognized previous episodes of subclinical antibody-mediated rejection occurred 4.5 ± 3.5 years before allograft loss. Explanted allografts with evidence of antibody-mediated rejection demonstrated higher endothelitis and microvascular inflammation scores (0.89 ± 0.26 and 2.25 ± 0.28, respectively) compared with explanted allografts without antibody-mediated rejection (0.42 ± 0.11 and 0.36 ± 0.09, p = 0.046 and p < 0.0001, respectively). Antibody-mediated injury was observed in 62.1% of failing allografts with pure coronary arteriosclerosis and mixed (arteriosclerosis and atherosclerosis) pattern, while it was not observed in patients with pure coronary atherosclerosis (p = 0.0076). We demonstrate that antibody-mediated rejection is operating in a substantial fraction of failing heart allografts and is associated with severe coronary arteriosclerosis. Unrecognized subclinical antibody-mediated rejection episodes may be observed years before allograft failure.

  13. Long-term outcome of cardiac allograft vasculopathy treated by transmyocardial laser revascularization: early rewards, late losses.

    PubMed

    Mehra, M R; Uber, P A; Prasad, A K; Park, M H; Scott, R L; McFadden, P M; Van Meter, C H

    2000-08-01

    Transmyocardial laser revascularization (TLR) was initially touted as a promising therapeutic alternative for tackling the growing problem of cardiac allograft vasculopathy in late heart transplant survivors. We first described 4- and 8-week observations of application of this surgical technique, in which we professed enthusiasm for TLR in providing symptomatic relief and in reducing ischemic burden. In this report, we present the long-term (24-month) impact of TLR on clinical outcome, channel patency, and recrudescence of ischemic burden. In the long term, surgical TLR provides neither consistent symptomatic improvement nor an ameliorative effect on the natural history of cardiac allograft vasculopathy.

  14. The Effect of Everolimus Initiation and Calcineurin Inhibitor Elimination on Cardiac Allograft Vasculopathy in De Novo Recipients: One-Year Results of a Scandinavian Randomized Trial.

    PubMed

    Arora, S; Andreassen, A K; Andersson, B; Gustafsson, F; Eiskjaer, H; Bøtker, H E; Rådegran, G; Gude, E; Ioanes, D; Solbu, D; Sigurdardottir, V; Dellgren, G; Erikstad, I; Solberg, O G; Ueland, T; Aukrust, P; Gullestad, L

    2015-07-01

    Early initiation of everolimus with calcineurin inhibitor therapy has been shown to reduce the progression of cardiac allograft vasculopathy (CAV) in de novo heart transplant recipients. The effect of de novo everolimus therapy and early total elimination of calcineurin inhibitor therapy has, however, not been investigated and is relevant given the morbidity and lack of efficacy of current protocols in preventing CAV. This 12-month multicenter Scandinavian trial randomized 115 de novo heart transplant recipients to everolimus with complete calcineurin inhibitor elimination 7-11 weeks after HTx or standard cyclosporine immunosuppression. Ninety-five (83%) patients had matched intravascular ultrasound examinations at baseline and 12 months. Mean (± SD) recipient age was 49.9 ± 13.1 years. The everolimus group (n = 47) demonstrated significantly reduced CAV progression as compared to the calcineurin inhibitor group (n = 48) (ΔMaximal Intimal Thickness 0.03 ± 0.06 and 0.08 ± 0.12 mm, ΔPercent Atheroma Volume 1.3 ± 2.3 and 4.2 ± 5.0%, ΔTotal Atheroma Volume 1.1 ± 19.2 mm(3) and 13.8 ± 28.0 mm(3) [all p-values ≤ 0.01]). Everolimus patients also had a significantly greater decline in levels of soluble tumor necrosis factor receptor-1 as compared to the calcineurin inhibitor group (p = 0.02). These preliminary results suggest that an everolimus-based CNI-free can potentially be considered in suitable de novo HTx recipients.

  15. Regulation of human aortic endothelial cell-derived mesenchymal growth factors by allogeneic lymphocytes in vitro. A potential mechanism for cardiac allograft vasculopathy.

    PubMed Central

    Wagner, C R; Morris, T E; Shipley, G D; Hosenpud, J D

    1993-01-01

    Cardiac allograft vasculopathy is thought to be triggered by an alloreactive response to the donor coronary vasculature, resulting in smooth muscle cell proliferation and ultimate occlusion of the donor coronary arteries. To determine whether allogeneic lymphocytes are capable of regulating endothelial-derived smooth muscle cell (SMC) growth factors, human aortic endothelial cells (HAECs) were exposed to allogeneic lymphocytes. The HAEC-lymphocyte co-cultures were assessed for (a) lymphocyte proliferation in response to the allogeneic HAECs; (b) release of soluble factors that stimulate human aortic SMC proliferation; and (c) alteration of HAEC mRNA levels for a panel of known SMC growth factors. Co-culture conditioned medium increased SMC proliferation, compared to medium conditioned by HAECs alone. HAECs exposed to allogeneic lymphocytes increased their expression of mRNA for basic fibroblast growth factor, transforming growth factors alpha and beta, and platelet derived growth factor A and B chains. These results demonstrate that allogeneic lymphocytes are capable of inducing HAECs to increase mRNA levels for several mesenchymal growth factors and to release bioactive products capable of stimulating SMC cell proliferation in vitro. Additionally, the data support the hypothesis that alloreactive lymphocytes can stimulate allogeneic donor endothelial cells to produce growth factors that may contribute to the intimal thickening seen in cardiac allograft vasculopathy. Images PMID:8376585

  16. Left main coronary artery stenosis treatment with two paclitaxel-eluting stents in a patient with cardiac allograft vasculopathy.

    PubMed

    Martínez-Ríos, Marco A; Méndez-Ortíz, Arturo; Gaspar, Jorge; Barragán-García, Rodolfo; Fernández-de-la-Reguera, Guillermo; González-Quesada, Carlos J

    2008-01-01

    Cardiac transplantation is a well defined therapy for end stage heart failure. After the first year of transplantation, allograft coronary artery disease (ACAD) is the second main cause of death. The ACAD is defined as a diffuse process affecting the entire length of epicardial vessels. Once ACAD has been established, treatments such as coronary angioplasty, coronary stenting, and coronary bypass are performed. We present a case of successful stenting of the left main coronary artery (LMCA) in a patient with ACAD. The patient's medical history was significant for heart transplantation due to ischemic heart failure. Four years after transplantation the patient was admitted again due to sudden worsening of New York Heart Association functional class and extreme fatigue. Coronary angiogram showed a severe stenosis in the proximal segment of the LMCA; we performed stenting with a paclitaxel-eluting stent (PES). Six months after the procedure, the patient had an elective angiogram, where we discovered a new severe occlusion distally to the former stent; a second PES was implanted. Fourteen months after the second stenting, a new elective angiogram was performed without evidence of in-stent restenosis. After a 8-year follow-up since transplantation, the patient is free from dyspnea, angina, and adverse cardiovascular events. Our report suggests the efficacy of PES as ACAD treatment of the unprotected LMCA.

  17. Mitochondrial vasculopathy

    PubMed Central

    Finsterer, Josef; Zarrouk-Mahjoub, Sinda

    2016-01-01

    Mitochondrial disorders (MIDs) are usually multisystem disorders (mitochondrial multiorgan disorder syndrome) either on from onset or starting at a point during the disease course. Most frequently affected tissues are those with a high oxygen demand such as the central nervous system, the muscle, endocrine glands, or the myocardium. Recently, it has been shown that rarely also the arteries may be affected (mitochondrial arteriopathy). This review focuses on the type, diagnosis, and treatment of mitochondrial vasculopathy in MID patients. A literature search using appropriate search terms was carried out. Mitochondrial vasculopathy manifests as either microangiopathy or macroangiopathy. Clinical manifestations of mitochondrial microangiopathy include leukoencephalopathy, migraine-like headache, stroke-like episodes, or peripheral retinopathy. Mitochondrial macroangiopathy manifests as atherosclerosis, ectasia of arteries, aneurysm formation, dissection, or spontaneous rupture of arteries. The diagnosis relies on the documentation and confirmation of the mitochondrial metabolic defect or the genetic cause after exclusion of non-MID causes. Treatment is not at variance compared to treatment of vasculopathy due to non-MID causes. Mitochondrial vasculopathy exists and manifests as micro- or macroangiopathy. Diagnosing mitochondrial vasculopathy is crucial since appropriate treatment may prevent from severe complications. PMID:27231520

  18. Chronic cardiac allograft rejection: critical role of ED-A(+) fibronectin and implications for targeted therapy strategies.

    PubMed

    Franz, Marcus; Neri, Dario; Berndt, Alexander

    2012-03-01

    Chronic cardiac allograft rejection is characterized by cardiac allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) causing severe long-term complications after heart transplantation and determining allograft function and patients' prognosis. Until now, there have been no sufficient preventive or therapeutic strategies. CAV and CIF are accompanied by changes in the extracellular matrix, including re-expression of the fetal fibronectin splice variant known as ED-A(+) fibronectin. This molecule has been shown to be crucial for the development of myofibroblasts (MyoFbs) as the main cell type in CIF and for the activation of vascular smooth muscle cells (VSMCs) as the main cell type in CAV. Relevant re-expression and protein deposition of ED-A(+) fibronectin has been demonstrated in animal models of chronic rejection, with spatial association to CAV and CIF, and a quantitative correlation to the rejection grade. The paper by Booth et al published in this issue of The Journal of Pathology could prove for the first time the functional importance of ED-A(+) fibronectin for the development of CIF as a main component of chronic cardiac rejection. Thus, promising conclusions for the development of new diagnostic, preventive, and therapeutic strategies for chronic cardiac rejection focusing on ED-A(+) fibronectin can be suggested.

  19. Graft vasculopathy in clinical hand transplantation.

    PubMed

    Kaufman, C L; Ouseph, R; Blair, B; Kutz, J E; Tsai, T M; Scheker, L R; Tien, H Y; Moreno, R; Ozyurekoglu, T; Banegas, R; Murphy, E; Burns, C B; Zaring, R; Cook, D F; Marvin, M R

    2012-04-01

    Allogeneic hand transplantation is now a clinical reality. While results have been encouraging, acute rejection rates are higher than in their solid-organ counterparts. In contrast, chronic rejections, as defined by vasculopathy and/or fibrosis and atrophy of skin and other tissues, as well as antibody mediated rejection, have not been reported in a compliant hand transplant recipient. Monitoring vascularized composite allograft (VCA) hand recipients for rejection has routinely involved punch skin biopsies, vascular imaging and graft appearance. Our program, which has transplanted a total of 6 hand recipients, has experience which challenges these precepts. We present evidence that the vessels, both arteries and veins may also be a primary target of rejection in the hand. Two of our recipients developed severe intimal hyperplasia and vasculopathy early post-transplant. An analysis of events and our four other patients has shown that the standard techniques used for surveillance of rejection (i.e. punch skin biopsies, DSA and conventional vascular imaging studies) are inadequate for detecting the early stages of vasculopathy. In response, we have initiated studies using ultrasound biomicroscopy (UBM) to evaluate the vessel wall thickness. These findings suggest that vasculopathy should be a focus of frequent monitoring in VCA of the hand.

  20. Significance of Anti-HLA Antibodies on Adult and Pediatric Heart Allograft Outcomes

    PubMed Central

    Mangiola, Massimo; Marrari, Marilyn; Feingold, Brian; Zeevi, Adriana

    2017-01-01

    As methods for human leukocyte antigens (HLA) antibody detection have evolved and newer solid phase assays are much more sensitive, the last 15 years has seen a renewed focus on the importance of HLA antibodies in solid organ transplant rejection. However, there is still much controversy regarding the clinical significance of antibody level as depicted by the mean fluorescence intensity of a patient’s neat serum. Emerging techniques, including those that identify antibody level and function, show promise for the detection of individuals at risk of allograft rejection, determination of the effectiveness of desensitization prior to transplant, and for monitoring treatment of rejection. Here, we review current publications regarding the relevance of donor-specific HLA antibodies (DSA) in adult and pediatric heart transplantation (HT) with graft survival, development of antibody-mediated rejection and cardiac allograft vasculopathy (CAV). The negative impact of DSA on patient and allograft survival is evident in adult and pediatric HT recipients. Many questions remain regarding the most appropriate frequency of assessment of pre- and posttransplant DSA as well as the phenotype of DSA memory vs. true de novo antibody using large multicenter adult and pediatric cohorts and state-of-the-art methodologies for DSA detection and characterization. PMID:28191005

  1. [Vasculitis and vasculopathy].

    PubMed

    Marković, Asjastipić

    2012-10-01

    Many pathophysiological process components are known to be implicated in lower limb ulcerations, among which vascular lesions have a major role. Vasculitis denotes a heterogeneous group of clinical entities which all are characterized by the inflammatory process of arterial and venous walls of any size and in any organ, quite frequently in the skin. Vasculopathy, on the other hand, refers to vascular and capillary lesions caused by, for example, some medications. The classification of vasculitides according to the size of the blood vessels involved serves for proper understanding the issue among clinicians and researchers, and not as a diagnostic tool. According to histologic finding obtained by examination of blood vessel biopsy specimen, vasculitides are divided into three groups: lymphocytic, leukocytoclastic and granulomatous. Livedoid vasculitis (livedo reticularis) most commonly affects women and is generally localized on lower extremities. The etiology oflivedoid vasculitis may imply autoimmune diseases, capillary obstruction with cryoglobulins, or antiphospholipid syndrome. Livedoid vasculopathy is a hyalinization disease of the vasculature, with thromboses and ulcerations on lower extremities, and of unknown etiology. Livedoid vasculopathy has been singled out as a separate disease that usually does not occur consequentially to other primary diseases. Livedoid vasculopathy typically affects women (71%) at a mean age of 45 (range 10-85) years; bilateral involvement of both lower limbs is present in 80.8%, disease manifested with ulcerations in 68.9%, ulcerations followed by development of atrophie blanche in 71.1%, transcutaneous oximetry reduction is found in 74.1%, factor V mutation (Leiden heterozygotes) in 22.2%, reduced protein C activity in 13.3%, prothrombin gene mutation (G20210A) in 8.3%, positive lupus anticoagulant in 17.9%, positive anticardiolipin antibodies in 28.6%, and elevated homocysteine level in 14.3% cases; blood vessel histology shows

  2. Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm.

    PubMed

    Khatibi, Kasra; Heit, Jeremy J; Telischak, Nicholas A; Elbers, Jorina M; Do, Huy M

    2015-06-24

    A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit.

  3. Cerebral vascular findings in PAPA syndrome: cerebral arterial vasculopathy or vasculitis and a posterior cerebral artery dissecting aneurysm.

    PubMed

    Khatibi, Kasra; Heit, Jeremy J; Telischak, Nicholas A; Elbers, Jorina M; Do, Huy M

    2016-08-01

    A young patient with PAPA (pyogenic arthritis, pyoderma gangrenosum, and acne) syndrome developed an unusual cerebral arterial vasculopathy/vasculitis (CAV) that resulted in subarachnoid hemorrhage from a ruptured dissecting posterior cerebral artery (PCA) aneurysm. This aneurysm was successfully treated by endovascular coil sacrifice of the affected segment of the PCA. The patient made an excellent recovery with no significant residual neurologic deficit.

  4. Is scleroderma a vasculopathy?

    PubMed

    Fleming, Jo Nadine; Nash, Richard A; Mahoney, William M; Schwartz, Stephen Mark

    2009-04-01

    Described as an autoimmune collagen vascular disease, the most striking feature of scleroderma may be a systemic vasculopathy. This vasculopathy includes characteristic noninflammatory macrovascular and microvascular changes with dramatic and possibly occlusive formation of a thickened neointima. Scleroderma vessels also have an unusual endothelial phenotype, with loss of normal markers including vascular endothelial (VE)-cadherin. These endothelial cells express type 1 interferon and regulator of G protein signaling 5 (RGS5), two molecules associated with vascular rarefaction. These genes may be important because tissue is hypoxic with high levels of vascular endothelial growth factor (VEGF), especially early in the disease. The combination of VEGF and rarefaction is not necessarily paradoxical. VEGF-mediated angiogenesis creates labile vessels that may not survive unless the vessel acquires a smooth muscle coat. The combination of interferon and RGS5 is consistent with an antiangiogenic phenotype. We offer a hypothesis that places vascular injury at the center of this disease and also suggest possible clinical approaches for arresting and/or reversing the disease.

  5. Varicella zoster vasculopathy.

    PubMed

    Mareedu, Jyotsna; Hanumaiah, Raghu Gowda; Hale, Elizabeth; Habte-Gabr, Eyassu

    2011-01-01

    Varicella-zoster virus can cause neurological disease in primary and reactivated latent forms, with a wide spectrum of disorders throughout a person's lifetime. 35-year-old male with AIDS; histoplasmosis; mild, intermittent asthma; and hypertension presented to hospital with left-sided weakness and slurred speech. Exam showed left hemiparesis with left upper motor neurons facial palsy and dysarthria. Acute right basal ganglia infarct was detected in head CT without contrast. A subsequent MRI showed acute non-hemorrhagic infarct, right basal ganglia; fusiform dilatation, and proximal right middle cerebral artery. A CT angiogram of the bilateral carotid arteries revealed occlusion of the right anterior cerebral artery with conical dilatation at the origin; significant stenosis, and dilatation of the right middle cerebral artery. These findings were consistent with vasculitis. Patient was successfully treated with IV acyclovir. Rapid diagnosis of VZV vasculopathy is important because it is a treatable cause of stroke. Mortality rate is 25% without treatment.

  6. Dermoscopic features of livedoid vasculopathy

    PubMed Central

    Hu, Stephen Chu-Sung; Chen, Gwo-Shing; Lin, Chi-Ling; Cheng, Yang-Chun; Lin, Yung-Song

    2017-01-01

    Abstract Livedoid vasculopathy (atrophie blanche) is a form of thrombotic vasculopathy. It is characterized by small ulcers that become crusted, and heal after several months to produce white atrophic scars. The most commonly affected sites are the lower legs, in particular the dorsum of the feet and ankles. To date, the dermoscopic features of livedoid vasculopathy have not been clearly described in the literature. In this observational study, we sought to evaluate the dermoscopic patterns of livedoid vasculopathy and determine whether the dermoscopic features are associated with certain histopathological characteristics. We evaluated 9 patients with livedoid vasculopathy by dermoscopy. Skin biopsy specimens were stained with hematoxylin and eosin for histopathologic examination, and dermoscopic features were correlated with histopathological characteristics. In the majority of patients with livedoid vasculopathy, examination with dermoscopy revealed central crusted ulcers or ivory white areas associated with peripheral pigmentation in a reticular pattern. In addition, increased vascular structures including linear and glomerular vessels were found. On histopathological examination, the central ivory white areas correlated with dermal fibrosis, the reticular pigmentation corresponded to epidermal basal layer hyperpigmentation or melanin within melanophages in the dermal papillae, and the vascular structures correlated with dilatation and proliferation of capillaries in the upper dermis. In summary, the most common dermoscopic features of livedoid vasculopathy identified in this study were central crusted ulcers or ivory white scar-like areas associated with peripheral reticular pigmentation and increased vascular structures. The characterization of dermoscopic criteria for livedoid vasculopathy may improve the accuracy in the clinical diagnosis and follow-up of this disease. PMID:28296736

  7. Sickle cell disease, vasculopathy, and therapeutics.

    PubMed

    Kassim, Adetola A; DeBaun, Michael R

    2013-01-01

    Sickle cell disease (SCD) is caused by a mutation in both beta globin genes, resulting in chronic hemolysis and multiorgan disease that ultimately leads to premature death. Although hemoglobin S (HbS) polymerization and vaso-occlusion are central to the pathogenesis of SCD, overlapping pathways implicated in SCD-related endothelial dysfunction include hemolysis, defects in nitric oxide metabolism, ischemia-reperfusion injury, oxidative stress, increased cell-to-cell adhesion, and proinflammatory and coagulation mediators. Progression of organ-specific vasculopathy often precedes organ dysfunction and may provide targets for therapeutic intervention. SCD-related vasculopathies include, but are not limited to, moyamoya that often precedes cerebral infarcts or hemorrhage, proliferative retinopathy prior to loss of eyesight, pulmonary vasculopathy associated with pulmonary hypertension, and renal vasculopathy prior to the onset of chronic renal disease. This review evaluates evidence that SCD vasculopathy is a harbinger for organ dysfunction and reviews the potential for targeted antivasculopathy therapies.

  8. Lupus vasculopathy: Diagnostic, pathogenetic and therapeutic considerations.

    PubMed

    Gonzalez-Suarez, M L; Waheed, A A; Andrews, D M; Ascherman, D P; Zeng, X; Nayer, A

    2014-04-01

    A rare form of vascular disease in systemic lupus erythematosus (SLE), lupus vasculopathy is characterized by necrosis and accumulation of immunoglobulins (IGs) and complements in the wall of arterioles and small arteries resulting in luminal narrowing. Lupus vasculopathy often accompanies lupus nephritis and portends a poor prognosis. Although there is general agreement on the treatment of lupus nephritis, effective treatment strategies for lupus vasculopathy remain to be defined. We report a 20-year-old woman with SLE who presented with generalized tonic-clonic seizure. Her immunosuppressive regimen consisted of mycophenolate mofetil, prednisone and hydroxychloroquine. On physical examination, she was Cushingoid in appearance and hypertensive. Laboratory tests indicated renal disease. Coagulation studies disclosed de novo lupus anticoagulant. Magnetic resonance imaging of the brain demonstrated acute focal cerebral hemorrhage. Echocardiography revealed reduced ejection fraction and severe mitral regurgitation. Despite high-dose glucocorticoids and mycophenolate mofetil, renal function remained poor. Kidney biopsy demonstrated lupus vasculopathy and glomerulonephritis. Plasma exchange therapy and intravenous cyclophosphamide were administered. Over the ensuing four weeks, renal function improved, complement levels increased, autoantibody titers decreased and lupus anticoagulant disappeared. In conclusion, lupus vasculopathy can occur in SLE despite a heavy immunosuppressive regimen. Antiphospholipid antibodies might be involved in the pathogenesis of lupus vasculopathy. Plasma exchange therapy in conjunction with intravenous cyclophosphamide may represent an effective treatment strategy for lupus vasculopathy.

  9. Renal infarction due to lupus vasculopathy.

    PubMed

    Varalaxmi, B; Sandeep, P; Sridhar, A V S S N; Raveendra, P; Kishore, C Krishna; Ram, R; Kumar, V Siva

    2015-08-01

    In the ISN/RPS 2003 classification of lupus nephritis (LN) renal vascular lesions are not mentioned. We present a patient with postpartum lupus vasculopathy. The renal biopsy in our patient showed concentric intimal thickening with narrowed lumen. No inflammatory changes were found. It also revealed immunoglobulin and complement deposition on the wall of the arteriole. These changes indicate lupus vasculopathy. The glomeruli revealed diffuse proliferative glomerulonephritis, with wire loops and cellular crescent in one glomerulus. The patient showed improvement with immunosuppression.

  10. Inducible nitric oxide synthase suppresses the development of allograft arteriosclerosis.

    PubMed Central

    Shears, L L; Kawaharada, N; Tzeng, E; Billiar, T R; Watkins, S C; Kovesdi, I; Lizonova, A; Pham, S M

    1997-01-01

    In cardiac transplantation, chronic rejection takes the form of an occlusive vasculopathy. The mechanism underlying this disorder remains unclear. The purpose of this study was to investigate the role nitric oxide (NO) may play in the development of allograft arteriosclerosis. Rat aortic allografts from ACI donors to Wistar Furth recipients with a strong genetic disparity in both major and minor histocompatibility antigens were used for transplantation. Allografts collected at 28 d were found to have significant increases in both inducible NO synthase (iNOS) mRNA and protein as well as in intimal thickness when compared with isografts. Inhibiting NO production with an iNOS inhibitor increased the intimal thickening by 57.2%, indicating that NO suppresses the development of allograft arteriosclerosis. Next, we evaluated the effect of cyclosporine (CsA) on iNOS expression and allograft arteriosclerosis. CsA (10 mg/kg/d) suppressed the expression of iNOS in response to balloon-induced aortic injury. Similarly, CsA inhibited iNOS expression in the aortic allografts, associated with a 65% increase in intimal thickening. Finally, we investigated the effect of adenoviral-mediated iNOS gene transfer on allograft arteriosclerosis. Transduction with iNOS using an adenoviral vector suppressed completely the development of allograft arteriosclerosis in both untreated recipients and recipients treated with CsA. These results suggest that the early immune-mediated upregulation in iNOS expression partially protects aortic allografts from the development of allograft arteriosclerosis, and that iNOS gene transfer strategies may prove useful in preventing the development of this otherwise untreatable disease process. PMID:9329968

  11. Polypoidal Choroidal Vasculopathy in Asians

    PubMed Central

    Wong, Chee Wai; Wong, Tien Y.; Cheung, Chui Ming Gemmy

    2015-01-01

    Age related macular degeneration (AMD) in Asians has been suggested to differ from their Western counterparts in terms of epidemiology, pathogenesis, clinical presentation and treatment. In particular, polypoidal choroidal vasculopathy (PCV) appears to be the predominant subtype of exudative AMD in Asian populations, in contrast to choroidal neovascularization secondary to AMD (CNV-AMD) in Western populations. Epidemiological data on PCV has been largely limited to hospital-based studies and there are currently no data on the incidence of PCV. Similarities and differences in risk factor profile between PCV and CNV-AMD point to some shared pathogenic mechanisms but also differential underlying mechanisms leading to the development of each phenotype. Serum biomarkers such as CRP, homocysteine and matrix metalloproteinases suggest underlying inflammation, atherosclerosis and deranged extracellular matrix metabolism as possible pathogenic mechanisms. In addition, recent advances in genome sequencing have revealed differences in genetic determinants of each subtype. While the standard of care for CNV-AMD is anti-vascular endothelial growth factor (VEGF) therapy, photodynamic therapy (PDT) has been the mainstay of treatment for PCV, although long-term visual prognosis remains unsatisfactory. The optimal treatment for PCV requires further clarification, particularly with different types of anti-VEGF agents and possible benefits of reduced fluence PDT. PMID:26239448

  12. Livedoid Thrombotic Vasculopathy Responding to Doxycycline Therapy

    PubMed Central

    Keller, Matthew S.; Lee, Jason

    2008-01-01

    Livedoid vasculopathy is a disease of the lower extremities that occurs predominantly in women. It begins as purpura and eventually ulcerates. Multiple causes have been posited, but many cases are found to be idiopathic. Many treatment modalities have been attempted to control the disease process, but many cases remain difficult to treat, and, at times, the treatments have side effects that limit treatment. This is a case report in a small number of patients tested in unblinded fashion. We report the effective use of doxycycline in the treatment of long-standing livedoid vasculopathy in two patients. PMID:21212844

  13. De novo expression of fetal ED-A(+) fibronectin and B (+) tenascin-C splicing variants in human cardiac allografts: potential impact for targeted therapy of rejection.

    PubMed

    Franz, Marcus; Matusiak-Brückner, Monika; Richter, Petra; Grün, Katja; Ziffels, Barbara; Neri, Dario; Maschek, Hansjörg; Schulz, Uwe; Pfeil, Alexander; Jung, Christian; Figulla, Hans R; Gummert, Jan; Berndt, Alexander; Renner, André

    2014-10-01

    Management of acute and especially chronic rejection after human cardiac transplantation is still challenging. Chronic rejection, represented by allograft vasculopathy (CAV) and cardiac interstitial fibrosis (CIF) is known to cause severe long-term complications. Rejection associated tissue-remodelling entails the reoccurrence of fetal variants of Fibronectin (Fn) and Tenascin-C (Tn-C), which are virtually absent in adult human organs. In a rat model, an extensive re-expression could be demonstrated for ED-A(+) Fn with spatial association to CAV and CIF. Thus, it is of great interest to investigate the cardiac tissue expression and distribution in human samples. From 48 heart transplanted patients, 64 tissue specimens derived from right ventricular biopsies were available. Histopathological analysis was performed according to the International Society for Heart and Lung Transplantation (ISHLT) guidelines for the detection of acute rejection. By immunohistochemistry, protein expression of ED-A(+) Fn, B(+) Tn-C, alpha-smooth muscle actin, CD31 and CD45 was assessed and analysed semiquantitatively. Co-localisation studies were performed by means of immunofluorescence double labelling. Histopathological analysis of the 64 samples revealed different ISHLT grades (0R in 36 cases, 1R in 20 cases and 2R in 8 cases). There was a distinct and quantitatively relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C in most samples. Semi-quantitative evaluation did not show any correlation to the acute rejection grade for all markers. Interestingly, significant correlations to the extent of inflammation could be shown for ED-A(+) Fn (r = 0.442, p = 0.000) and B(+) Tn-C (r = 0.408, p = 0.001) as well as between both proteins (r = 0.663, p = 0.000). A spatial association of ED-A(+) Fn and B(+) Tn-C to CAV and CIF could be demonstrated. A relevant re-occurrence of ED-A(+) Fn and B(+) Tn-C following human heart transplantation could be demonstrated with spatial association to

  14. Cerebral vasculopathy in children with sickle cell anemia.

    PubMed

    Fasano, Ross M; Meier, Emily R; Hulbert, Monica L

    2015-01-01

    Sickle cell anemia (SCA)-associated cerebral vasculopathy and moyamoya is a unique entity reflecting the abnormal interactions between sickled red blood cells (RBCs) and the cerebral arterial endothelium. Endothelial injury, coagulation activation, and the inflammatory response generated by sickled RBCs are implicated in the development of cerebral vasculopathy, but the pathophysiology remains incompletely understood. SCA-specific screening and treatment guidelines have successfully reduced the incidence of overt strokes in this high-risk population. However, despite aggressive hematological management, many children with cerebral vasculopathy due to SCA have progressive vasculopathy and recurrent strokes; therefore, more effective therapies, such as revascularization surgery and curative hematopoietic stem cell transplant, are urgently needed.

  15. [Large vessels vasculopathy in systemic sclerosis].

    PubMed

    Tejera Segura, Beatriz; Ferraz-Amaro, Iván

    2015-12-07

    Vasculopathy in systemic sclerosis is a severe, in many cases irreversible, manifestation that can lead to amputation. While the classical clinical manifestations of the disease have to do with the involvement of microcirculation, proximal vessels of upper and lower limbs can also be affected. This involvement of large vessels may be related to systemic sclerosis, vasculitis or atherosclerotic, and the differential diagnosis is not easy. To conduct a proper and early diagnosis, it is essential to start prompt appropriate treatment. In this review, we examine the involvement of large vessels in scleroderma, an understudied manifestation with important prognostic and therapeutic implications.

  16. Cutaneous collagenous vasculopathy: A rare case report

    PubMed Central

    Rambhia, Kinjal Deepak; Hadawale, Snehal D.; Khopkar, Uday S.

    2016-01-01

    Cutaneous collagenous vasculopathy (CCV) is a distinct, rare, and underdiagnosed condition. We report a case of CCV in a 50-year-old woman presenting as asymptomatic, erythematous to hyperpigmented nonblanchable macules over both the lower extremities. The clinical differential diagnosis of the lesions was pigmented purpuric dermatoses (Schamberg's purpura) and cutaneous small vessel vasculitis. Histology of the lesions revealed dilated superficial dermal vessels with abundant pink hyaline material in the vessel wall, which stained with periodic acid Schiff stain. The patient was diagnosed as CCV. This condition remains largely underdiagnosed and is commonly mistaken for pigmented purpuric dermatosis or generalized essential telangiectasia. Emphasis on the differentiation of CCV from its clinical and histological mimicks is made. PMID:26955587

  17. Livedoid vasculopathy managed with hyperbaric oxygen therapy

    PubMed Central

    Bhutani, Sourabh; Verma, Rohit; Verghese, George

    2012-01-01

    Livedoid vasculopathy is an uncommon condition resulting in painful lower extremity ulceration and scarring. This condition presents as purpuric macules and papules that progress to painful, irregular ulcers of the lower legs and dorsal feet. These ulcerations are often recurrent and chronic with spontaneous remissions and exacerbations that may be seasonal. The first case, a 22-year-old female presented with three-year history of recurrent multiple non-healing ulcers involving feet and ankles. The ulcers were associated with severe debilitating pain and paraesthesia, as a result of which she was unable to walk without support. Patient was administered HBOT at pressure of 2.5ATA for 1 h daily, six days a week. After ten sittings of HBOT, patient reported a drastic reduction in the pain along with reduction in the dose of analgesic by half and a definite improvement in her walking. The second case was a 49-year-old male who also had history of recurrent ulceration on the dorsum of feet and ankles associated with severe pain. With HBOT, the patient felt an improvement in pain and ambulation by the 8th sitting and complete relief from pain by the 17th sitting. HBOT is a recognized modality of treatment of various problem wounds and non-healing ulcers due to various etiologies. The above two cases show that it can be a useful treatment modality for livedoid vasculopathy where other treatment modalities have failed and therefore could be given to a larger number of patients in hospitals where it is available. PMID:24532913

  18. Livedoid vasculopathy and its association with factor V Leiden mutation.

    PubMed

    Yong, Angeline Anning; Tan, Audrey Wei Hsia; Giam, Yoke Chin; Tang, Mark Boon Yang

    2012-12-01

    Livedoid vasculopathy is a rare chronic relapsing disorder characterised by recurrent painful thrombotic and vasculitic ulcers on the legs. We present the cases of two Indian women with livedoid vasculopathy that were found to be associated with an underlying factor V Leiden heterozygous mutation. There were no other thrombotic manifestations, and livedoid vasculopathy was the sole presenting feature of the factor V Leiden mutation, although this could also be coincidental. Initial treatment with high-dose immunosuppressive therapy was suboptimal, and the addition of pentoxifylline and antiplatelet therapy was crucial in achieving disease control and remission. These cases highlight the possible association with an underlying prothrombotic disorder, such as factor V Leiden mutation, in patients with livedoid vasculopathy. Although this association is relatively uncommon, it is more relevant to Indian patients, as the presence of factor V Leiden mutation is highest in this ethnicity as compared to the local Malay and Chinese populations.

  19. Local gene therapy with indoleamine 2,3-dioxygenase protects against development of transplant vasculopathy in chronic kidney transplant dysfunction.

    PubMed

    Vavrincova-Yaghi, D; Deelman, L E; van Goor, H; Seelen, M A; Vavrinec, P; Kema, I P; Gomolcak, P; Benigni, A; Henning, R H; Sandovici, M

    2016-11-01

    Chronic transplant dysfunction (CTD) is the primary cause of late allograft loss in kidney transplantation. Indoleamine 2,3-dioxygenase (IDO) is involved in fetomaternal tolerance and IDO gene therapy inhibits acute rejection following kidney transplantation. The aim of this study is to investigate whether gene therapy with IDO is able to attenuate CTD. Transplantation was performed in a rat Dark-Agouti to Wistar-Furth CTD model. Donor kidneys were incubated either with an adenovirus carrying IDO gene, a control adenovirus or saline. During the first 10 days recipients received low-dose cyclosporine. Body weight, blood pressure, serum creatinine and proteinuria were measured every 2 weeks. Rats were killed after 12 weeks. IDO had a striking beneficial effect on transplant vasculopathy at week 12. It also significantly improved body weight gain; it reduced blood pressure and decreased proteinuria during the follow-up. However, it did not affect the kidney function. In addition, IDO therapy significantly decreased the number of graft-infiltrating macrophages at week 12. The messenger RNA levels of forkhead box p3 and transforming grow factor-β were elevated in the IDO treated group at week 12. Here we show for first time a clear beneficial effect of local IDO gene therapy especially on transplant vasculopathy in a rat model of renal CTD.

  20. Morphologic and immunohistochemical findings in antibody-mediated rejection of the cardiac allograft.

    PubMed

    Fishbein, Gregory A; Fishbein, Michael C

    2012-12-01

    The recognition and acceptance of the entity of antibody-mediated rejection (AMR) of solid organs has been slow to develop. Greatest acceptance and most information relates to cardiac transplantation. AMR is thought to represent antibody/complement mediated injury to the microvasculature of the graft that can result in allograft dysfunction, allograft loss, accelerated graft vasculopathy, and increased mortality. The morphologic hallmark is microvascular injury with immunoglobulin and complement deposition in capillaries, accumulation of intravascular macrophages, and in more severe cases, microvascular hemorrhage and thrombosis, with inflammation and edema of the affected organ. Understanding of the pathogenesis of AMR, criteria and methods for diagnosis, and treatment strategies are still in evolution, and will be addressed in this review.

  1. Intellectual Ability and Executive Function in Pediatric Moyamoya Vasculopathy

    ERIC Educational Resources Information Center

    Williams, Tricia S.; Westmacott, Robyn; Dlamini, Nomazulu; Granite, Leeor; Dirks, Peter; Askalan, Rand; MacGregor, Daune; Moharir, Mahendranath; Deveber, Gabrielle

    2012-01-01

    Aim: Moyamoya vasculopathy is characterized by progressive stenosis of the major arteries of the Circle of Willis, resulting in compromised cerebral blood flow and increased risk of stroke. The objectives of the current study were to examine intellectual and executive functioning of children with moyamoya and to evaluate the impact of moyamoya…

  2. Are Cav1.3 pacemaker channels in chromaffin cells?

    PubMed Central

    Striessnig, Joerg

    2011-01-01

    Mouse and rat chromaffin cells (MCCs, RCCs) fire spontaneously at rest and their activity is mainly supported by the two L-type Ca2+ channels expressed in these cells (Cav1.2 and Cav1.3). Using Cav1.3−/− KO MCCs we have shown that Cav1.3 possess all the prerequisites for carrying subthreshold currents that sustain low frequency cell firing near resting (0.5 to 2 Hz at −50 mV):1 low-threshold and steep voltage dependence of activation, slow and incomplete inactivation during pulses of several hundreds of milliseconds. Cav1.2 contributes also to pacemaking MCCs and possibly even Na+ channels may participate in the firing of a small percentage of cells. We now show that at potentials near resting (−50 mV), Cav1.3 carries equal amounts of Ca2+ current to Cav1.2 but activates at 9 mV more negative potentials. MCCs express only TTX-sensitive Nav1 channels that activate at 24 mV more positive potentials than Cav1.3 and are fully inactivating. Their blockade prevents the firing only in a small percentage of cells (13%). This suggests that the order of importance with regard to pacemaking MCCs is: Cav1.3, Cav1.2 and Nav1. The above conclusions, however, rely on the proper use of DHPs, whose blocking potency is strongly holding potential dependent. We also show that small increases of KCl concentration steadily depolarize the MCCs causing abnormally increased firing frequencies, lowered and broadened AP waveforms and an increased facility of switching “non-firing” into “firing” cells that may lead to erroneous conclusions about the role of Cav1.3 and Cav1.2 as pacemaker channels in MCCs.2 PMID:21406973

  3. Regulation of aldosterone secretion by Cav1.3

    PubMed Central

    Xie, Catherine B.; Haris Shaikh, Lalarukh; Garg, Sumedha; Tanriver, Gizem; Teo, Ada E. D.; Zhou, Junhua; Maniero, Carmela; Zhao, Wanfeng; Kang, Soosung; Silverman, Richard B.; Azizan, Elena A. B.; Brown, Morris J.

    2016-01-01

    Aldosterone-producing adenomas (APAs) vary in phenotype and genotype. Zona glomerulosa (ZG)-like APAs frequently have mutations of an L-type calcium channel (LTCC) CaV1.3. Using a novel antagonist of CaV1.3, compound 8, we investigated the role of CaV1.3 on steroidogenesis in the human adrenocortical cell line, H295R, and in primary human adrenal cells. This investigational drug was compared with the common antihypertensive drug nifedipine, which has 4.5-fold selectivity for the vascular LTCC, CaV1.2, over CaV1.3. In H295R cells transfected with wild-type or mutant CaV1.3 channels, the latter produced more aldosterone than wild-type, which was ameliorated by 100 μM of compound 8. In primary adrenal and non-transfected H295R cells, compound 8 decreased aldosterone production similar to high concentration of nifedipine (100 μM). Selective CaV1.3 blockade may offer a novel way of treating primary hyperaldosteronism, which avoids the vascular side effects of CaV1.2-blockade, and provides targeted treatment for ZG-like APAs with mutations of CaV1.3. PMID:27098837

  4. Differential zinc permeation and blockade of L-type Ca2+ channel isoforms Cav1.2 and Cav1.3.

    PubMed

    Park, So-Jung; Min, Se-Hong; Kang, Ho-Won; Lee, Jung-Ha

    2015-10-01

    Certain voltage-activated Ca2+ channels have been reported to act as potential zinc entry routes. However, it remains to be determined whether zinc can permeate individual Ca2+ channel isoforms. We expressed recombinant Ca2+ channel isoforms in Xenopus oocytes and attempted to record zinc currents from them using a two-electrode voltage clamp method. We found that, in an extracellular zinc solution, inward currents arising from zinc permeation could be recorded from Xenopus oocytes expressing L-type Cav1.2 or Cav1.3 isoforms, but not from oocytes expressing Cav2.2, Cav2.3, Cav3.1, or Cav3.2. Zinc currents through Cav1.2 and Cav1.3 were blocked by nimodipine, but enhanced by (±)Bay K8644, supporting the finding that zinc can permeate both L-type Cav1.2 and Cav1.3 channel isoforms. We also examined the blocking effects of low concentrations of zinc on Ca2+ currents through the L-type channel isoforms. Low micro-molar zinc potently blocked Ca2+ currents through Cav1.2 and Cav1.3 with different sensitivities (IC50 for Cav1.2 and Cav1.3=18.4 and 34.1 μM) and de-accelerated the activation and inactivation kinetics in a concentration-dependent manner. Notably, mild acidifications of the external zinc solution increased zinc currents through Cav1.2 and Cav1.3, with the increment level for Cav1.3 being greater than that for Cav1.2. In overall, we provide evidence that Cav1.2 and Cav1.3 isoforms are capable of potentially functioning as zinc permeation routes, through which zinc entry can be differentially augmented by mild acidifications.

  5. Hyperglycemia-Induced Vasculopathy in the Murine Vitelline Vasculature

    PubMed Central

    Pinter, Emese; Mahooti, Sepi; Wang, Yi; Imhof, Beat A.; Madri, Joseph A.

    1999-01-01

    Maternal diabetes mellitus is associated with an increased incidence of congenital abnormalities as well as embryonic and perinatal lethality. In particular, a wide range of cardiovascular abnormalities have been noted in children of diabetic mothers and in the offspring of diabetic animals. The vascular system is the first organ system to develop in the embryo and is critical for normal organogenesis. The organization of mesodermal cells into endothelial and hematopoietic cells and into a complex vascular system is, in part, mediated by a series of specific cell-cell, cell-extracellular matrix, and cell-factor interactions. PECAM-1 expression has been observed during the earliest stages of vasculogenesis, and changes in PECAM-1 tyrosine phosphorylation have been associated with endothelial cell migration, vasculogenesis, and angiogenesis both in vitro and in vivo. In this report we demonstrate that exposure to hyperglycemia during gastrulation causes yolk sac and embryonic vasculopathy in cultured murine conceptuses and in the conceptuses of streptozotocin-induced diabetic pregnant mice. In addition, we correlate the presence of yolk sac and embryonic vasculopathy with the failure of PECAM-1 tyrosine dephosphorylation during the formation of blood islands/vessels from clusters of extra-embryonic and embryonic angioblasts in the murine conceptus using both in vitro and in vivo models. The importance of these findings in the development of vasculopathy in the offspring of diabetic mothers and the potential effects and benefits of glucose regulation during the periods of vasculogenesis/angiogenesis in embryonic development are discussed. PMID:10329590

  6. Common variants near CAV1 and CAV2 are associated with primary open-angle glaucoma in Caucasians from the USA.

    PubMed

    Wiggs, Janey L; Kang, Jae Hee; Yaspan, Brian L; Mirel, Daniel B; Laurie, Cathy; Crenshaw, Andrew; Brodeur, Wendy; Gogarten, Stephanie; Olson, Lana M; Abdrabou, Wael; DelBono, Elizabeth; Loomis, Stephanie; Haines, Jonathan L; Pasquale, Louis R

    2011-12-01

    Primary open-angle glaucoma (POAG) is a genetically complex common disease characterized by progressive optic nerve degeneration that results in irreversible blindness. Recently, a genome-wide association study (GWAS) for POAG in an Icelandic population identified significant associations with single nucleotide polymorphisms (SNPs) between the CAV1 and CAV2 genes on chromosome 7q31. In this study, we confirm that the identified SNPs are associated with POAG in our Caucasian US population and that specific haplotypes located in the CAV1/CAV2 intergenic region are associated with the disease. We also present data suggesting that associations with several CAV1/CAV2 SNPs are significant mostly in women.

  7. Proinflammatory cytokines and matrix metalloproteinases in CSF of patients with VZV vasculopathy

    PubMed Central

    Jones, Dallas; Alvarez, Enrique; Selva, Sean; Gilden, Don

    2016-01-01

    Objective: To determine the levels of proinflammatory cytokines and matrix metalloproteinases (MMPs) in the CSF of patients with virologically verified varicella zoster virus (VZV) vasculopathy. Methods: CSF from 30 patients with virologically verified VZV vasculopathy was analyzed for levels of proinflammatory cytokines and MMPs using the Meso Scale Discovery multiplex ELISA platform. Positive CNS inflammatory disease controls were provided by CSF from 30 patients with multiple sclerosis. Negative controls were provided by CSF from 20 healthy controls. Results: Compared to multiple sclerosis CSF and CSF from healthy controls, levels of interleukin (IL)-8, IL-6, and MMP-2 were significantly elevated in VZV vasculopathy CSF. Conclusions: CSF of patients with VZV vasculopathy revealed a unique profile of elevated proinflammatory cytokines, IL-8 and IL-6, along with elevated MMP-2. The relevance of these cytokines to the pathogenesis of VZV vasculopathy requires further study. PMID:27340684

  8. Photodynamic therapy for polypoidal choroidal vasculopathy secondary to choroidal nevus

    PubMed Central

    Wong, James G; Lai, Xin Jie; Sarafian, Richard Y; Wong, Hon Seng; Smith, Jeremy B

    2017-01-01

    We report a case of a Caucasian female who developed active polypoidal choroidal vasculopathy (PCV) at the edge of a stable choroidal nevus and was successfully treated with verteporfin photodynamic therapy. No active polyp was detectable on indocyanine green angiography 2 years after treatment, and good vision was maintained. Indocyanine green angiography is a useful investigation to diagnose PCV and may be underutilized. Unlike treatment of choroidal neovascularization secondary to choroidal nevus, management of PCV secondary to nevus may not require intravitreal anti-vascular endothelial growth factor therapy. Photodynamic monotherapy may be an effective treatment of secondary PCV. PMID:28243154

  9. MicroRNAs in control of gene regulatory programs in diabetic vasculopathy.

    PubMed

    Pei, Chongzhe; Zhang, Xiaoping; Meng, Shu; Li, Yigang

    2017-01-01

    Diabetes is generally associated with vasculopathy, which contains both microvascular and macrovascular complications, associated with high morbidity and mortality. Currently, despite interventional therapy, the overall prognosis for patients with diabetic vasculopathy remains unsatisfactory. Angiogenesis and vascular injury and repair are associated with a variety of cells. However, the molecular mechanisms of the cells that are involved in pathogenesis of diabetic vasculopathy remain largely unknown. As novel molecules, microRNAs (miRs) take part in regulating protein-coding gene expression at the post-transcriptional level, and contribute to the pathogenesis of various types of chronic metabolism disease, especially diabetic vasculopathy. This allows miRs to have a direct function in regulation of various cellular events. Additionally, circulating miRs have been proposed as biomarkers for a wide range of cardiovascular diseases. This review elucidates miR-mediated regulatory mechanisms in diabetic vasculopathy. Furthermore, we discuss the current understanding of miRs in diabetic vasculopathy. Finally, we summarize the development of novel diagnostic and therapeutic strategies for diabetic vasculopathy related to miRs.

  10. Adenohypophysitis in rat pituitary allografts

    PubMed Central

    Rotondo, Fabio; Quintanar-Stephano, Andres; Asa, Sylvia L; Lombardero, Matilde; Berczi, Istvan; Scheithauer, Bernd W; Horvath, Eva; Kovacs, Kalman

    2010-01-01

    The histological, immunohistochemical and ultrastructural alterations in 81 pituitary allografts from Lewis rats transplanted beneath the renal capsule of Wistar rats were investigated. Intrasellar pituitaries of rats bearing allografts were also examined. Recipient rats were sacrificed at various time points after transplantation. Two days after transplantation, the central portion of the allografts demonstrated ischaemic necrosis. A week later, massive mononuclear cell infiltrates consisting primarily of lymphocytes and to a lesser extent, macrophages, plasma cells and granulocytes became prominent. At about three to four weeks after transplantation, the mononuclear cell infiltrate diminished; the surviving adenohypophysial cells, mainly prolactin (PRL) cells, increased in number and necrosis was replaced by connective tissue. No histological changes were noted in the intrasellar pituitaries of rats bearing allografts. Immunohistochemistry demonstrated that the surviving adenohypophysial cells were mainly PRL-producing cells. Electron microscopy revealed adenohypophysial cell destruction, a spectrum of inflammatory cells and, in late phase, accumulation of fibroblasts and collagen fibres. PRL cells were the prominent cell types; they increased in number. It appears that pituitary allografts are ‘foreign’ and evoke an immune response, suggesting that they may be used as an experimental animal model for morphological investigation of the development and progression of adenohypophysitis, a rare disease occurring mainly in young women often associated with pregnancy. PMID:20586813

  11. Osteochondral Allograft of the Talus

    PubMed Central

    Bisicchia, Salvatore; Rosso, Federica; Amendola, Annunziato

    2014-01-01

    Osteochondral lesions of the talus are being recognized as an increasingly common injury. They are most commonly located postero-medially or antero-laterally, while centrally located lesions are uncommon. Large osteochondral lesions have significant biomechanical consequences and often require resurfacing with osteochondral autograft transfer, mosaicplasty, autologous chondrocyte implantation (or similar methods) or osteochondral allograft transplantation. Allograft procedures have become popular due to inherent advantages over other resurfacing techniques. Cartilage viability is one of the most important factors for successful clinical outcomes after transplantation of osteochondral allografts and is related to storage length and intra-operative factors. While there is abundant literature about osteochondral allograft transplantation in the knee, there are few papers about this procedure in the talus. Failure of non-operative management, initial debridement, curettage or microfractures are an indication for resurfacing. Patients should have a functional ankle motion, closed growth plates, absence of cartilage lesions on the tibial side. This paper reviews the published literature about osteochondral allograft transplantation of the talus focusing on indications, pre-operative planning, surgical approaches, postoperative management, results and complications of this procedure. PMID:25328456

  12. Ontogenic Changes and Differential Localization of T-type Ca2+ Channel Subunits Cav3.1 and Cav3.2 in Mouse Hippocampus and Cerebellum

    PubMed Central

    Aguado, Carolina; García-Madrona, Sebastián; Gil-Minguez, Mercedes; Luján, Rafael

    2016-01-01

    T-type calcium (Ca2+) channels play a central role in regulating membrane excitability in the brain. Although the contributions of T-type current to neuron output is often proposed to reflect a differential distribution of T-type channel subtypes to somato-dendritic compartments, their precise subcellular distributions in central neurons are not fully determined. Using histoblot and high-resolution immunoelectron microscopic techniques, we have investigated the expression, regional distribution and subcellular localization of T-type Cav3.1 and Cav3.2 channel subunits in the adult brain, as well as the ontogeny of expression during postnatal development. Histoblot analysis showed that Cav3.1 and Cav3.2 proteins were widely expressed in the brain, with mostly non-overlapping patterns. Cav3.1 showed the highest expression level in the molecular layer (ml) of the cerebellum (Cb), and Cav3.2 in the hippocampus (Hp) and the ml of Cb. During development, levels of Cav3.1 and Cav3.2 increased with age, although there were marked region- and developmental stage-specific differences in their expression. At the cellular and subcellular level, immunoelectron microscopy showed that labeling for Cav3.1 was present in somato-dendritic domains of hippocampal interneurons and Purkinje cells (PCs), while Cav3.2 was present in somato-dendritic domains of CA1 pyramidal cells, hippocampal interneurons and PCs. Most of the immunoparticles for Cav3.1 and Cav3.2 were either associated with the plasma membrane or the intracellular membranes, with notable differences depending on the compartment. Thus, Cav3.1 was mainly located in the plasma membrane of interneurons, whereas Cav3.2 was mainly located in the plasma membrane of dendritic spines and had a major intracellular distribution in dendritic shafts. In PCs, Cav3.1 and Cav3.2 showed similar distribution patterns. In addition to its main postsynaptic distribution, Cav3.2 but not Cav3.1 was also detected in axon terminals establishing

  13. Tissue allografts and health risks.

    PubMed

    Delloye, C

    1994-01-01

    Like vascularized transplants, tissue allografts are able to transmit viral and bacterial diseases. Transmission of HIV (Human Immunodeficiency Virus) and HCV (Hepatitis C virus) has been proved for sterilized, unprocessed and deep-frozen allografts. It is the prime responsibility of the tissue bank to select the donor correctly and to perform careful biological screening. However, standard screening is not enough to detect a seronegative but contaminated donor. It is necessary to quarantine the tissues until complementary screening confirms the absence of viral disease. If secondary screening is not possible, the tissues should be discarded or should be processed. If donor selection, relevant and appropriate screening tests and adequate procurement of tissues are carefully made, then the risk of disease transmission from tissue allografts will remain remote.

  14. Biomechanical properties of bone allografts

    SciTech Connect

    Pelker, R.R.; Friedlaender, G.E.; Markham, T.C.

    1983-04-01

    The biomechanical properties of allograft bone can be altered by the methods chosen for its preservation and storage. These effects are minimal with deep-freezing or low-level radiation. Freeze-drying, however, markedly diminishes the torsional and bending strength of bone allografts but does not deleteriously affect the compressive or tensile strength. Irradiation of bone with more than 3.0 megarad or irradiation combined with freeze-drying appears to cause a significant reduction in breaking strength. These factors should be considered when choosing freeze-dried or irradiated allogeneic bone that will be subjected to significant loads following implantation.

  15. Metabolic memory: mechanisms and implications for diabetic vasculopathies.

    PubMed

    Zhang, ErLi; Wu, YongJian

    2014-08-01

    In the past decades, a persistent progression of diabetic vascular complications despite reversal of hyperglycemia has been observed in both experimental and clinical studies. This durable effect of prior hyperglycemia on the initiation and progression of diabetic vasculopathies was defined as "metabolic memory". Subsequently, enhanced glycation of cellular proteins and lipids, sustained oxidative stress, and prolonged inflammation were demonstrated to mediate this phenomenon. Recently, emerging evidence strongly suggests that epigenetic modifications may account for the molecular and phenotypic changes associated with hyperglycemic memory. In this review, we presented an overview on the discovery of metabolic memory, the recent progress in its molecular mechanisms, and the future implications related to its fundamental research and clinical application.

  16. Radiation-induced large intracranial vessel occlusive vasculopathy

    SciTech Connect

    Brant-Zawadzki, M.; Anderson, M.; DeArmond, S.J.; conley, F.K.; Jahnke, R.W.

    1980-01-01

    Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features of these two cases are discussed and previously reported cases are reviewed.

  17. Focal choroidal excavation associated with polypoidal choroidal vasculopathy.

    PubMed

    Say, Emil Anthony T; Jani, Pooja D; Appenzeller, Matthew F; Houghton, Odette M

    2013-01-01

    A 48-year-old woman presented with blurred vision in her right eye for 6 weeks. Visual acuity was 20/300 and 20/25 in the right and left eyes, respectively. Fundus examination showed subretinal hemorrhage in the superonasal macula in the right eye, whereas the left eye was normal. Fluorescein angiography showed blocked fluorescence from hemorrhage and a round distinct hypofluorescent spot along the inferotemporal arcade. Indocyanine green angiography revealed hyperfluorescent tubular and aneurysmal dilatations consistent with polypoidal choroidal vasculopathy in the superior macula. Spectral-domain optical coherence tomography showed retinal pigment epithelial irregularities and detachment. Scans through the round area of hypofluorescence revealed a conforming focal choroidal excavation and thinning of the underlying choriocapillaries. Because the pathogenesis of focal choroidal excavation is currently unclear, the authors propose the possibility of an acquired etiology related to loss of choriocapillaries from perfusion abnormalities as evidenced here.

  18. Lupus vasculopathy combined with acute renal failure in lupus nephritis.

    PubMed

    Wu, Chien-Te; Fu, Lin-Shien; Wen, Mei-Chin; Hung, Shein-Chung; Chi, Ching-Shiang

    2003-12-01

    Several risk factors have been associated with the prognosis of lupus nephritis. However, few studies have focused on renal vascular lesions (such as thrombi due to immune complexes) as a prognostic factor in this disease. Here we present a case of systemic lupus erythematosus (SLE) in a 12-year-old girl who exhibited acute renal failure and severe hypertension on admission. Renal pathology findings included diffuse proliferative glomerulonephritis (class IVb) and lupus vasculopathy (LV) with immune complex deposition within glomerular capillaries and the preglomerular arteriolar lumen. Her clinical condition deteriorated rapidly, even after cyclophosphamide and methylprednisolone pulse therapy. It improved after 5 days of plasmapheresis and remained stable for up to 6 months under regular treatment. We suggest that renal biopsy performed early in SLE patients with renal involvement should be studied carefully for the presence of vascular lesions. Additionally, plasmapheresis can be considered in patients with LV refractory to other modalities of therapy.

  19. Genetic, Cellular, and Functional Evidence for Ca2+ Inflow through Cav1.2 and Cav1.3 Channels in Murine Spiral Ganglion Neurons

    PubMed Central

    Lv, Ping; Kim, Hyo Jeong; Lee, Jeong-Han; Sihn, Choong-Ryoul; Fathabad Gharaie, Somayeh; Mousavi-Nik, Atefeh; Wang, Wenying; Wang, Hong-Gang; Gratton, Michael Anne; Doyle, Karen J.; Zhang, Xiao-Dong; Chiamvimonvat, Nipavan

    2014-01-01

    Spiral ganglion neurons (SGNs) of the eighth nerve serve as the bridge between hair cells and the cochlear nucleus. Hair cells use Cav1.3 as the primary channel for Ca2+ inflow to mediate transmitter release. In contrast, SGNs are equipped with multiple Ca2+ channels to mediate Ca2+-dependent functions. We examined directly the role of Cav1.3 channels in SGNs using Cav1.3-deficient mice (Cav1.3−/−). We revealed a surprising finding that SGNs functionally express the cardiac-specific Cav1.2, as well as neuronal Cav1.3 channels. We show that evoked action potentials recorded from SGNs show a significant decrease in the frequency of firing in Cav1.3−/− mice compared with wild-type (Cav1.3+/+) littermates. Although Cav1.3 is the designated L-type channel in neurons, whole-cell currents recorded in isolated SGNs from Cav1.3−/− mice showed a surprising remnant current with sensitivity toward the dihydropyridine (DHP) agonist and antagonist, and a depolarization shift in the voltage-dependent activation compared with that in the Cav1.3+/+ mice. Indeed, direct measurement of the elementary properties of Ca2+ channels, in Cav1.3+/+ neurons, confirmed the existence of two DHP-sensitive single-channel currents, with distinct open probabilities and conductances. We demonstrate that the DHP-sensitive current in Cav1.3−/− mice is derived from Cav1.2 channel activity, providing for the first time, to our knowledge, functional data for the expression of Cav1.2 currents in neurons. Finally, using shRNA gene knockdown methodology, and histological analyses of SGNs from Cav1.2+/− and Cav1.3+/− mice, we were able to establish the differential roles of Cav1.2 and Cav1.3 in SGNs. PMID:24849370

  20. Varicella-Zoster Virus Vasculopathy: A Case Report Demonstrating Vasculitis using Black-Blood MRI

    PubMed Central

    Shah, Jay; Poonawala, Husain; Keay, Susan K; Serulle, Yafell; Steven, Andrew; Gandhi, Dheeraj; Cole, John W

    2016-01-01

    Infections are rare but important causes of stroke. Among these, varicella zoster virus has been known to cause ischemic stroke. During an attack of herpes zoster ophthalmicus, it has been hypothesized that the virus replicates in the trigeminal ganglion and travels via the trigeminal nerve centrally to cause cerebral vasculopathy. Here we present a case of a 69 year-old Caucasian immunocompromised woman who suffered recurrent ischemic infarcts within the same vascular distribution following an episode of zoster ophthalmicus three months prior. An imaging technique termed black-blood magnetic resonance imaging was utilized to aid in the diagnosis of cerebral vasculitis. The case is used to provide a literature review of the pathogenesis, diagnosis, and treatment of cerebral varicella zoster vasculopathy. In situations where an isolated unilateral cerebral vasculopathy is identified, neurologists are urged to consider varicella zoster as a treatable etiologic agent, as untreated vasculopathy can lead to further strokes. PMID:27065314

  1. Interleukin-6, A Cytokine Critical to Mediation of Inflammation, Autoimmunity and Allograft Rejection: Therapeutic Implications of IL-6 Receptor Blockade.

    PubMed

    Jordan, Stanley C; Choi, Jua; Kim, Irene; Wu, Gordon; Toyoda, Mieko; Shin, Bonga; Vo, Ashley

    2017-01-01

    The success of kidney transplants is limited by the lack of robust improvements in long-term survival. It is now recognized that alloimmune responses are responsible for the majority of allograft failures. Development of novel therapies to decrease allosensitization is critical. The lack of new drug development in kidney transplantation necessitated repurposing drugs initially developed in oncology and autoimmunity. Among these is tocilizumab (anti-IL-6 receptor [IL-6R]) which holds promise for modulating multiple immune pathways responsible for allograft injury and loss. Interleukin-6 is a cytokine critical to proinflammatory and immune regulatory cascades. Emerging data have identified important roles for IL-6 in innate immune responses and adaptive immunity. Excessive IL-6 production is associated with activation of T-helper 17 cell and inhibition of regulatory T cell with attendant inflammation. Plasmablast production of IL-6 is critical for initiation of T follicular helper cells and production of high-affinity IgG. Tocilizumab is the first-in-class drug developed to treat diseases mediated by IL-6. Data are emerging from animal and human studies indicating a critical role for IL-6 in mediation of cell-mediated rejection, antibody-mediated rejection, and chronic allograft vasculopathy. This suggests that anti-IL-6/IL-6R blockade could be effective in modifying T- and B-cell responses to allografts. Initial data from our group suggest anti-IL-6R therapy is of value in desensitization and prevention and treatment of antibody-mediated rejection. In addition, human trials have shown benefits in treatment of graft versus host disease in matched or mismatched stem cell transplants. Here, we explore the biology of IL-6/IL-6R interactions and the evidence for an important role of IL-6 in mediating allograft rejection.

  2. Emphysema in the renal allograft

    SciTech Connect

    Potter, J.L.; Sullivan, B.M.; Fluornoy, J.G.; Gerza, C.

    1985-04-01

    Two diabetic patients in whom emphysematous pyelonephritis developed after renal transplantation are described. Clinical recognition of this unusual and serious infection is masked by the effects of immunosuppression. Abdominal radiographic, ultrasound, and computed tomography findings are discussed. The clinical presentation includes urinary tract infection, sepsis, and acute tubular malfunction of the allograft in insulin-dependent diabetics.

  3. Cav1.2, but not Cav1.3, L-type calcium channel subtype mediates nicotine-induced conditioned place preference in miceo.

    PubMed

    Liu, Yudan; Harding, Meghan; Dore, Jules; Chen, Xihua

    2017-04-03

    Nicotine use is one of the most common forms of drug addiction. Although L-type calcium channels (LTCCs) are involved in nicotine addiction, the contribution of the two primary LTCC subtypes (Cav1.2 and 1.3) is unknown. This study aims to determine the contribution of these two LTCC subtypes to nicotine-induced conditioned place preference (CPP) responses by using transgenic mouse models that do not express Cav1.3 (Cav1.3(-/-)) or contain a mutation in the dihydropyridine (DHP) site of the Cav1.2 (Cav1.2DHP(-/-)). We found a hyperbolic dose dependent nicotine (0.1-1mg/kg; 0.5mg/kg optimum) effect on place preference in wild type (WT) mice, that could be prevented by the DHP LTCC blocker nifedipine pretreatment. Similarly, Cav1.3(-/-) mice showed nicotine-induced place preference which was antagonized by nifedipine. In contrast, nifedipine pretreatment of Cav1.2DHP(-/-) mice had no effect on nicotine-induced CPP responses, suggesting an involvement of Cav1.2 subtype in the nicotine-induced CPP response. Nifedipine alone failed to produce either conditioned place aversion or CPP in WT mice. These results collectively indicate Cav1.2, but not Cav1.3 LTCC subtype regulates, at least in part, the reinforcing effects of nicotine use.

  4. PDL1 is required for peripheral transplantation tolerance and protection from chronic allograft rejection.

    PubMed

    Tanaka, Katsunori; Albin, Monica J; Yuan, Xueli; Yamaura, Kazuhiro; Habicht, Antje; Murayama, Takaya; Grimm, Martin; Waaga, Ana Maria; Ueno, Takuya; Padera, Robert F; Yagita, Hideo; Azuma, Miyuki; Shin, Tahiro; Blazar, Bruce R; Rothstein, David M; Sayegh, Mohamed H; Najafian, Nader

    2007-10-15

    The PD-1:PDL pathway plays an important role in regulating alloimmune responses but its role in transplantation tolerance is unknown. We investigated the role of PD-1:PDL costimulatory pathway in peripheral and a well established model of central transplantation tolerance. Early as well as delayed blockade of PDL1 but not PDL2 abrogated tolerance induced by CTLA4Ig in a fully MHC-mismatched cardiac allograft model. Accelerated rejection was associated with a significant increase in the frequency of IFN-gamma-producing alloreactive T cells and expansion of effector CD8(+) T cells in the periphery, and a decline in the percentage of Foxp3(+) graft infiltrating cells. Similarly, studies using PDL1/L2-deficient recipients confirmed the results with Ab blockade. Interestingly, while PDL1-deficient donor allografts were accepted by wild-type recipients treated with CTLA4Ig, the grafts developed severe chronic rejection and vasculopathy when compared with wild-type grafts. Finally, in a model of central tolerance induced by mixed allogeneic chimerism, engraftment was not abrogated by PDL1/L2 blockade. These novel data demonstrate the critical role of PDL1 for induction and maintenance of peripheral transplantation tolerance by its ability to alter the balance between pathogenic and regulatory T cells. Expression of PDL1 in donor tissue is critical for prevention of in situ graft pathology and chronic rejection.

  5. Common variants near CAV1 and CAV2 are associated with primary open-angle glaucoma in Caucasians from the USA

    PubMed Central

    Wiggs, Janey L.; Hee Kang, Jae; Yaspan, Brian L.; Mirel, Daniel B.; Laurie, Cathy; Crenshaw, Andrew; Brodeur, Wendy; Gogarten, Stephanie; Olson, Lana M.; Abdrabou, Wael; DelBono, Elizabeth; Loomis, Stephanie; Haines, Jonathan L.; Pasquale, Louis R.

    2011-01-01

    Primary open-angle glaucoma (POAG) is a genetically complex common disease characterized by progressive optic nerve degeneration that results in irreversible blindness. Recently, a genome-wide association study (GWAS) for POAG in an Icelandic population identified significant associations with single nucleotide polymorphisms (SNPs) between the CAV1 and CAV2 genes on chromosome 7q31. In this study, we confirm that the identified SNPs are associated with POAG in our Caucasian US population and that specific haplotypes located in the CAV1/CAV2 intergenic region are associated with the disease. We also present data suggesting that associations with several CAV1/CAV2 SNPs are significant mostly in women. PMID:21873608

  6. Osteochondral allografts in arm and forearm surgery.

    PubMed

    Delloye, C; De Nayer, P; Vincent, A

    1991-01-01

    Osteochondral allografting can restore the skeletal continuity anatomically after a limb salvage procedure. Evaluation of the clinical function indicates that a good result can be anticipated. Fracture was the most frequent complication, and the fixation technique we used initially predisposed the problem. The major advantage of allograft is the possibility of reinsertion of soft tissue to help stabilize the new joint. In addition, any part of the limb can potentially be reconstructed with an allograft.

  7. Treatment application of rivaroxaban in Chinese patients with livedoid vasculopathy

    PubMed Central

    Chen, Wenji; Fan, Lina; Wang, Yanyan; Deng, Xiaohu

    2017-01-01

    Livedoid vasculopathy (LV) is a chronic prothrombotic disease of cutaneous micro-circulation resulting in cutaneous ischemia and infarction. As a rare disease, LV has an estimated incidence of ten cases per million. Not only correct diagnosis but also effective treatments are very difficult for patients with LV. Due to the lack of large-scale studies in this rare disease, LV poses a great challenge to the doctors, and existing treatment has always been an individual attempt with off-label application. The main goals in the treatment of patients with LV are to avoid the repeated occurrence of active cutaneous lesions and prevent painful ulceration and irreversible scarring. The current report describes the cases of three Chinese patients with LV receiving rivaroxaban treatment, an oral direct inhibitor of factor Xa inhibitor, and observes the treatment effect of rivaroxaban during the follow-up. As an injection-free alternative to low-molecular-weight heparin (LMWP) and monitoring-free alternative to warfarin, rivaroxaban improves the quality of life and enhances the compliance of patients. All patients consider rivaroxaban as more tolerable than previous drugs and, therefore, continue the application of rivaroxaban, effectively improving the treatment effect of drugs and successfully avoiding the repeated occurrence of active cutaneous lesions. Treatment application of rivaroxaban in Chinese patients with LV successfully avoids the recurrence of active cutaneous lesions and prevents the progressive ulceration and scarring. PMID:28360530

  8. An Electronic Health Record Investigation of Lenticulostriate Vasculopathy Features.

    PubMed

    Frankovich, Jennifer; Egan, Maximillian; Mahony, Talia; Benitz, William; Shaw, Gary

    2017-02-01

    Objective Lenticulostriate vasculopathy (LSV) is characterized by linear hyperechogenicities in the basal ganglia found on the head ultrasounds of infants. We reviewed electronic health records of infants with and without LSV to investigate whether physician dictations indicated symptoms which could reflect subtle basal ganglia injury. Study Design In a case-control study, we analyzed data from 46 infants with LSV and 127 controls. Infants were stratified between term and preterm birth. Odds ratios (ORs) and 95% confidence intervals were calculated for tone abnormalities, apnea, feeding difficulties, seizures, and movement abnormalities in the presence of LSV. Results Both term and preterm infants with LSV showed elevated risks for tone abnormalities (OR: 3.6 and 2.9, respectively). Term infants with LSV showed elevated risks for hypotonia (OR: 4.3), apnea (OR: 2.9), and feeding difficulties (OR: 4.1). Preterm infants with LSV showed elevated risks for truncal hypotonia (OR: 3.9) and hyperreflexia (OR: 3.9). Conclusion Our findings provide some evidence that LSV is associated with an increased risk of early signs of abnormal development, possibly relating to signs of subtle basal ganglia injury. Historically LSV has been considered incidental. The associations identified here suggest that LSV findings are worthy of further study.

  9. Analysis of the Serum Lipid Profile in Polypoidal Choroidal Vasculopathy

    PubMed Central

    Li, Miaoling; Zhang, Xiongze; Liao, Nanying; Ye, Baikang; Peng, Yuting; Ji, Yuying; Wen, Feng

    2016-01-01

    Polypoidal choroidal vasculopathy (PCV), the predominant subtype of neovascular age-related macular degeneration in the Asian population, is associated with genetic polymorphism of lipid metabolism. In this study, we performed the untargeted lipidomics approach of ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS) to reveal the potential discriminating lipid profile of PCV patients in serum (21 PCV patients and 19 age-matched controls). Unsupervised principal component, supervised orthogonal partial least squares analysis, correlation analysis, and heatmap analysis were performed with the data obtained by UPLC-MS. Forty–one discriminating metabolites were identified. Receiver operating characteristic curve analysis, pathway analysis and functional analysis were performed subsequently, and platelet-activating factor (PAF) was further selected as the key indicator of the distinct lipid metabolism in PCV patients. Finally, the serum level of PAF was validated by enzyme-linked immunosorbent assay, which is significantly higher in PCV patients compared to controls (65 PCV patients and 63 age-matched controls, p < 0.0001), consistent with the UPLC-MS analysis. Our results suggested that PAF is considered as the major indicator of the distinct lipid metabolism in PCV patients. PMID:27910906

  10. PREFACE: 9th International Symposium on Cavitation (CAV2015)

    NASA Astrophysics Data System (ADS)

    Farhat, M.; Müller, A.

    2015-12-01

    It is our pleasure and privilege to welcome all the participants of the 9th International Symposium on Cavitation (CAV2015) to Lausanne. Since its initiation in 1986 in Sendai, Japan, the CAV symposium has grown to become the world's foremost event dedicated to cavitation. Hosted by EPFL (Ecole Polytechnique Fédérale de Lausanne) and staged at the SwissTech Convention Center, CAV2015 is a unique opportunity to exchange with leading scientists and industry experts about the latest advances in theoretical modelling, numerical simulation and experimentation related to cavitation phenomena with a special emphasis on practical applications. The topics covered by CAV2015 include cavitation in ¬fluid machinery and fuel systems, bubble dynamics, cavitation erosion, advanced numerical simulation, sonochemistery, biomedicine and experimental techniques. CAV2015 will also host an exhibition of leading providers of state of the art measurement equipment, including high-speed imaging systems, non-intrusive velocimetry, pressure sensors, as well as numerical solvers. We have accepted over 190 papers, which will be presented in four parallel sessions. The proceedings will appear in the open access Journal of Physics: Conference Series (JPCS), which is part of the IOP Conference Series. All published papers are fully citable and upon publication will be free to download in perpetuity. We would like to thank all the reviewers for their great help during the selection process. We will also propose six plenary speakers to highlight cavitation issues in different fields. Finally, we would like to warmly thank our sponsors for their valuable support and the local Organizing Committee for the efforts in setting up this important event. We look forward to seeing you in Lausanne!

  11. Shear stress-induced mechanotransduction protein deregulation and vasculopathy in a mouse model of progeria

    PubMed Central

    2014-01-01

    Introduction A mouse model of progeria derived by insertion of the human mutant LMNA gene (mLMNA), producing mutant lamin A, shows loss of smooth muscle cells in the media of the ascending aorta. We hypothesized that high shear stress, in the presence of mutant lamin A, induces this vasculopathy and tried to define the molecular and cellular basis for aortic vasculopathy. Methods Ascending and descending aortas from wild type (WT) and mLMNA+ mice were compared using proteomics, Western blots, PCR and immunostaining. To determine whether high fluidic shear stress, known to occur in the ascending aorta, contributed to the vasculopathy, we exposed descending aortas of mLMNA+ mice, with no apparent vasculopathy, to 75 dynes/cm2 shear stress for 30 minutes using a microfluidic system. Results When the mice were one year of age, expression of several mechanotransduction proteins in the ascending aorta, including vimentin, decreased in mLMNA+ mice but no decrease occurred in the descending aorta. High fluidic shear stress produced a significant reduction in vimentin of mLMNA+ mice but not in similarly treated WT mice. Conclusions The occurrence of mutant lamin A and high shear stress correlate with a reduction in the level of mechanotransduction proteins in smooth muscle cells of the media. Reduction of these proteins may contribute over time to development of vasculopathy in the ascending aorta in progeria syndrome. PMID:24661531

  12. First-trimester features of Fowler syndrome (hydrocephaly-hydranencephaly proliferative vasculopathy).

    PubMed

    Laurichesse-Delmas, H; Beaufrère, A M; Martin, A; Kaemmerlen, A G; Déchelotte, P; Lémery, D

    2002-12-01

    We describe the features of Fowler syndrome (proliferative vasculopathy and hydrocephaly-hydranencephaly) diagnosed in the first trimester. The pregnancy with no significant family history was referred for karyotyping and ultrasound examination after a cystic hygroma was seen at 12 weeks. At 13 weeks, ultrasound examination revealed hydrocephaly-hydranencephaly, fetal akinesia, and arthrogryposis associated with increased nuchal translucency. The parents opted for termination of pregnancy and the diagnosis of Fowler syndrome was confirmed by pathological examination of the fetus. Calcified necrotic lesions and proliferative vasculopathy were observed in the entire central nervous system including the brainstem and spinal cord. Cases previously reported in siblings suggest an autosomal recessive transmission but specific genetic antenatal diagnosis is not yet available. The diagnosis of proliferative vasculopathy and hydrocephaly-hydranencephaly (Fowler syndrome) should be considered whenever hydrocephaly-hydranencephaly associated with a fetal akinetic sequence are encountered at the end of the first trimester. Genetic counseling is recommended.

  13. Lectin-like oxidized low-density lipoprotein receptor (LOX-1) in sickle cell disease vasculopathy.

    PubMed

    Chen, Mingyi; Qiu, Hong; Lin, Xin; Nam, David; Ogbu-Nwobodo, Lucy; Archibald, Hannah; Joslin, Amelia; Wun, Ted; Sawamura, Tatsuya; Green, Ralph

    2016-09-01

    Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL. Increased expression of LOX-1 has been demonstrated in atherosclerotic lesions and diabetic vasculopathy. In this study, we investigate the expression of LOX-1 receptor in sickle cell disease (SCD) vasculopathy. Expression of LOX-1 in brain vascular endothelium is markedly increased and LOX-1 gene expression is upregulated in cultured human brain microvascular endothelial cells by incubation with SCD erythrocytes. Also, the level of circulating soluble LOX-1 concentration is elevated in the plasma of SCD patients. Increased LOX-1 expression in endothelial cells is potentially involved in the pathogenesis of SCD vasculopathy. Soluble LOX-1 concentration in SCD may provide a novel biomarker for risk stratification of sickle cell vascular complications.

  14. Lectin-like oxidized low-density lipoprotein receptor (LOX-1) in sickle cell disease vasculopathy

    PubMed Central

    Chen, Mingyi; Qiu, Hong; Lin, Xin; Nam, David; Ogbu-Nwobodo, Lucy; Archibald, Hannah; Joslin, Amelia; Wun, Ted; Sawamura, Tatsuya; Green, Ralph

    2017-01-01

    Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL. Increased expression of LOX-1 has been demonstrated in atherosclerotic lesions and diabetic vasculopathy. In this study, we investigate the expression of LOX-1 receptor in sickle cell disease (SCD) vasculopathy. Expression of LOX-1 in brain vascular endothelium is markedly increased and LOX-1 gene expression is upregulated in cultured human brain microvascular endothelial cells by incubation with SCD erythrocytes. Also, the level of circulating soluble LOX-1 concentration is elevated in the plasma of SCD patients. Increased LOX-1 expression in endothelial cells is potentially involved in the pathogenesis of SCD vasculopathy. Soluble LOX-1 concentration in SCD may provide a novel biomarker for risk stratification of sickle cell vascular complications. PMID:27519944

  15. Varicella-Zoster Virus Vasculopathy: The Growing Association Between Herpes Zoster and Strokes.

    PubMed

    Powell, David R; Patel, Shiddhi; Franco-Paredes, Carlos

    2015-09-01

    Varicella-zoster virus (VZV) is herpes virus that after its reactivation from nerve ganglia to cause herpes zoster may lead to a variety of neurologic complications, including encephalitis, meningitis, retinal necrosis or myelitis. In addition, VZV can spread to arteries in the central nervous system and cause hemorrhagic or ischemic complications due to an inflammatory vasculopathy. In fact, there is a growing epidemiological and clinical recognition that there is an association between VZV reactivation and subsequent strokes. Herein, we present a case of an immune compromised individual with reactivation of VZV causing dermatomal herpes zoster followed by multifocal vasculopathy. We also review the literature to highlight key aspects of VZV-associated vasculopathy.

  16. Alternative Splicing Generates a Novel Truncated Cav1.2 Channel in Neonatal Rat Heart*

    PubMed Central

    Liao, Ping; Yu, Dejie; Hu, Zhenyu; Liang, Mui Cheng; Wang, Jue Jin; Yu, Chye Yun; Ng, Gandi; Yong, Tan Fong; Soon, Jia Lin; Chua, Yeow Leng; Soong, Tuck Wah

    2015-01-01

    L-type Cav1.2 Ca2+ channel undergoes extensive alternative splicing, generating functionally different channels. Alternatively spliced Cav1.2 Ca2+ channels have been found to be expressed in a tissue-specific manner or under pathological conditions. To provide a more comprehensive understanding of alternative splicing in Cav1.2 channel, we systematically investigated the splicing patterns in the neonatal and adult rat hearts. The neonatal heart expresses a novel 104-bp exon 33L at the IVS3-4 linker that is generated by the use of an alternative acceptor site. Inclusion of exon 33L causes frameshift and C-terminal truncation. Whole-cell electrophysiological recordings of Cav1.233L channels expressed in HEK 293 cells did not detect any current. However, when co-expressed with wild type Cav1.2 channels, Cav1.233L channels reduced the current density and altered the electrophysiological properties of the wild type Cav1.2 channels. Interestingly, the truncated 3.5-domain Cav1.233L channels also yielded a dominant negative effect on Cav1.3 channels, but not on Cav3.2 channels, suggesting that Cavβ subunits is required for Cav1.233L regulation. A biochemical study provided evidence that Cav1.233L channels enhanced protein degradation of wild type channels via the ubiquitin-proteasome system. Although the physiological significance of the Cav1.233L channels in neonatal heart is still unknown, our report demonstrates the ability of this novel truncated channel to modulate the activity of the functional Cav1.2 channels. Moreover, the human Cav1.2 channel also contains exon 33L that is developmentally regulated in heart. Unexpectedly, human exon 33L has a one-nucleotide insertion that allowed in-frame translation of a full Cav1.2 channel. An electrophysiological study showed that human Cav1.233L channel is a functional channel but conducts Ca2+ ions at a much lower level. PMID:25694430

  17. Evaluating Polypoidal Choroidal Vasculopathy With Optical Coherence Tomography Angiography

    PubMed Central

    Wang, Min; Zhou, Yao; Gao, Simon S.; Liu, Wei; Huang, Yongheng; Huang, David; Jia, Yali

    2016-01-01

    Purpose We observed and analyzed the morphologic characteristics of polypoidal lesions and abnormal branching vascular network (BVN) in patients with polypoidal choroidal vasculopathy (PCV) by optical coherence tomography angiography (OCTA). Methods A retrospective observational case series was done of patients with PCV. All patients were scanned with a 70-kHz spectral-domain OCT system using the split-spectrum amplitude-decorrelation angiography (SSADA) algorithm to distinguish blood flow from static tissue. The OCTA images of these patients were compared to those from indocyanine green angiography (ICGA). Semiautomated segmentation was used to further analyze the polypoidal lesion and the BVN. Results We studied 13 eyes of 13 patients 51 to 69 years old. A total of 11 patients were treatment-naive. Two patients had multiple anti-VEGF injections and one underwent photodynamic therapy (PDT). Optical coherence tomography angiography was able to detect the BVN in all cases. Using cross-sectional OCTA, BVN locations were shown to be in the space between the RPE and Bruch's membrane. Using en face OCTA, the BVN vascular pattern could be shown more clearly than by ICGA. Polypoidal lesions showed high flow signals in different patterns in 12 cases in the outer retina slab. Using cross-sectional OCTA, the polyps were shown to be just below the top of the pigment epithelial detachment (PED). In one case, the polypoidal lesion was not detectable at the outer retina slab. Conclusions Optical coherence tomography angiography is a noninvasive imaging tool for detecting vascular changes in PCV. Branching vascular networks showed more clearly on OCTA than on ICGA. Polypoidal lesions had variable patterns on OCTA and were not always detected. The OCTA patterns of the polypoidal lesions and the BVN are helpful in understanding the pathology of PCV. PMID:27472276

  18. Vasculopathy and pulmonary hypertension in sickle cell disease.

    PubMed

    Potoka, Karin P; Gladwin, Mark T

    2015-02-15

    Sickle cell disease (SCD) is an autosomal recessive disorder in the gene encoding the β-chain of hemoglobin. Deoxygenation causes the mutant hemoglobin S to polymerize, resulting in rigid, adherent red blood cells that are entrapped in the microcirculation and hemolyze. Cardinal features include severe painful crises and episodic acute lung injury, called acute chest syndrome. This population, with age, develops chronic organ injury, such as chronic kidney disease and pulmonary hypertension. A major risk factor for developing chronic organ injury is hemolytic anemia, which releases red blood cell contents into the circulation. Cell free plasma hemoglobin, heme, and arginase 1 disrupt endothelial function, drive oxidative and inflammatory stress, and have recently been referred to as erythrocyte damage-associated molecular pattern molecules (eDAMPs). Studies suggest that in addition to effects of cell free plasma hemoglobin on scavenging nitric oxide (NO) and generating reactive oxygen species (ROS), heme released from plasma hemoglobin can bind to the toll-like receptor 4 to activate the innate immune system. Persistent intravascular hemolysis over decades leads to chronic vasculopathy, with ∼10% of patients developing pulmonary hypertension. Progressive obstruction of small pulmonary arterioles, increase in pulmonary vascular resistance, decreased cardiac output, and eventual right heart failure causes death in many patients with this complication. This review provides an overview of the pathobiology of hemolysis-mediated endothelial dysfunction and eDAMPs and a summary of our present understanding of diagnosis and management of pulmonary hypertension in sickle cell disease, including a review of recent American Thoracic Society (ATS) consensus guidelines for risk stratification and management.

  19. Genomic Variant in CAV1 Increases Susceptibility to Coronary Artery Disease and Myocardial Infarction

    PubMed Central

    Zhang, Rongfeng; Wang, Fan; Xu, Chaoping; Huang, Yufeng; Li, Sisi; Yin, Dan; Xiong, Xin; Li, Xiuchun; Chen, Qiuyun; Tu, Xin; Yang, Yanzong; Xia, Yonglong; Xu, Chengqi; Wang, Qing K.

    2016-01-01

    Background The CAV1 gene encodes caveolin-1 expressed in cell types relevant to atherosclerosis. Cav-1-null mice showed a protective effect on atherosclerosis under the ApoE−/− background. However, it is unknown whether CAV1 is linked to CAD and MI in humans. In this study we analyzed a tagSNP for CAV1 in intron 2, rs3807989, for potential association with CAD. Methods and Results We performed case-control association studies in three independent Chinese Han populations from GeneID, including 1,249 CAD cases and 841 controls in Population I, 1,260 cases and 833 controls in Population II and 790 cases and 1,212 controls in Population III (a total of 3,299 cases and 2,886 controls). We identified significant association between rs3807989 and CAD in three independent populations and in the combined population (Padj=2.18×10−5, OR=1.19 for minor allele A). We also detected significant association between rs3807989 and MI (Padj=5.43×10−5, OR=1.23 for allele A). Allele A of SNP rs3807989 was also associated with a decreased level of LDL cholesterol. Although rs3807989 is a tagSNP for both CAV1 and nearby CAV2, allele A of SNP rs3807989 was associated with an increased expression level of CAV1 (both mRNA and protein), but not CAV2. Conclusions The data in this study demonstrated that rs3807989 at the CAV1/CAV2 locus was associated with significant risk of CAD and MI by increasing expression CAV1 (but not CAV2). Thus, CAV1 becomes a strong candidate susceptibility gene for CAD/MI in humans. PMID:26775120

  20. Unilateral livedoid vasculopathy associated with involutional phase of cutaneous infantile hemangioma: the connection to coagulation disorders.

    PubMed

    Criado, Paulo Ricardo; Alavi, Afsaneh; Halpern, Ilana; Sotto, Mirian Nacagami; Kirsner, Robert S

    2013-12-01

    Livedoid vasculopathy is a bilateral painful and recurrent cutaneous ulcerative disorder of the legs that leads to atrophie blanche, atrophic white-porcelain scars, and is associated with disorders of fibrinolysis and/or coagulation. We present a young boy with an association between livedoid vasculopathy in the area of a previous involuted cutaneous hemangioma. We found 4 uncommon abnormalities associated with thrombo-occlusive events: heterozygous 20210 A→G genotype of prothrombin, reduced activity of anticoagulation proteins C and S, and elevated lipoprotein (a).

  1. Osteochondral Allografts in the Ankle Joint

    PubMed Central

    Vannini, Francesca; Buda, Roberto; Ruffilli, Alberto; Cavallo, Marco; Giannini, Sandro

    2013-01-01

    Purpose: The aim of this systematic review is to report about the clinical use of partial and total fresh osteochondral allograft in the ankle joint. The state of the art of allografts with regard to basic science, procurement and storage methods, immunogenicity, generally accepted indications and contraindications, and the rationale of the allografting procedure have been described. Methods: All studies published in PubMed from 2000 to January 2012 addressing fresh osteochondral allograft procedures in the ankle joint were identified, including those that fulfilled the following criteria: (a) level I-IV evidence addressing the areas of interest outlined above; (b) measures of functional, clinical, or imaging outcome; and (c) outcome related to ankle cartilage lesions or ankle arthritis treated by allografts. Results: The analysis showed a progressively increasing number of articles from 2000. The number of selected articles was 14; 9 of those focused on limited dimension allografts (plugs, partial) and 5 on bipolar fresh osteochondral allografts. The evaluation of evidence level showed 14 case series and no randomized studies. Conclusions: Fresh osteochondral allografts are now a versatile and suitable option for the treatment of different degrees of osteochondral disease in the ankle joint and may even be used as total joint replacement. Fresh osteochondral allografts used for total joint replacement are still experimental and might be considered as a salvage procedure in otherwise unsolvable situations. A proper selection of the patients is therefore a key point. Moreover, the patients should be adequately informed about the possible risks, benefits, and alternatives to the allograft procedure. PMID:26069666

  2. Antimitogenic effect of Larrea divaricata Cav.: participation in arachidonate metabolism.

    PubMed

    Anesini, C; Genaro, A; Cremaschi, G; Sterin Borda, L; Borda, E

    1999-02-01

    Aqueous extracts of the leaves of Larrea divaricata Cav. exert antimitogenic effects on tumor cells (BW 5147 murine immature T-lymphoma) and normal, stimulated lymphocytes. The effective concentration was four times smaller in the case of tumor cells than in the case of normal, stimulated lymphocytes. Inhibitor studies of arachidonate pathway suggest that the proliferative effect of the extract is due to the activation of lipoxygenase metabolism, while the inhibitory action could be a direct effect.

  3. High prevalence of antibodies against canine adenovirus (CAV) type 2 in domestic dog populations in South Africa precludes the use of CAV-based recombinant rabies vaccines.

    PubMed

    Wright, N; Jackson, F R; Niezgoda, M; Ellison, J A; Rupprecht, C E; Nel, L H

    2013-08-28

    Rabies in dogs can be controlled through mass vaccination. Oral vaccination of domestic dogs would be useful in the developing world, where greater vaccination coverage is needed especially in inaccessible areas or places with large numbers of free-roaming dogs. From this perspective, recent research has focused on development of new recombinant vaccines that can be administered orally in a bait to be used as adjunct for parenteral vaccination. One such candidate, a recombinant canine adenovirus type 2 vaccine expressing the rabies virus glycoprotein (CAV2-RG), is considered a promising option for dogs, given host specificity and safety. To assess the potential use of this vaccine in domestic dog populations, we investigated the prevalence of antibodies against canine adenovirus type 2 in South African dogs. Blood was collected from 241 dogs from the Gauteng and KwaZulu-Natal provinces. Sampled dogs had not previously been vaccinated against canine adenovirus type 1 (CAV1) or canine adenovirus type 2 (CAV2). Animals from both provinces had a high percentage of seropositivity (45% and 62%), suggesting that CAV2 circulates extensively among domestic dog populations in South Africa. Given this finding, we evaluated the effect of pre-existing CAV-specific antibodies on the efficacy of the CAV2-RG vaccine delivered via the oral route in dogs. Purpose-bred Beagle dogs, which received prior vaccination against canine parvovirus, canine distemper virus and CAV, were immunized by oral administration of CAV2-RG. After rabies virus (RABV) infection all animals, except one vaccinated dog, developed rabies. This study demonstrated that pre-existing antibodies against CAV, such as naturally occurs in South African dogs, inhibits the development of neutralizing antibodies against RABV when immunized with a CAV-based rabies recombinant vaccine.

  4. Radiation sterilization of skin allograft

    NASA Astrophysics Data System (ADS)

    Kairiyama, E.; Horak, C.; Spinosa, M.; Pachado, J.; Schwint, O.

    2009-07-01

    In the treatment of burns or accidental loss of skin, cadaveric skin allografts provide an alternative to temporarily cover a wounded area. The skin bank facility is indispensable for burn care. The first human skin bank was established in Argentina in 1989; later, 3 more banks were established. A careful donor selection is carried out according to the national regulation in order to prevent transmissible diseases. As cadaveric human skin is naturally highly contaminated, a final sterilization is necessary to reach a sterility assurance level (SAL) of 10 -6. The sterilization dose for 106 batches of processed human skin was determined on the basis of the Code of Practice for the Radiation Sterilization of Tissue Allografts: Requirements for Validation and Routine Control (2004) and ISO 11137-2 (2006). They ranged from 17.6 to 33.4 kGy for bioburdens of >10-162.700 CFU/100 cm 2. The presence of Gram negative bacteria was checked for each produced batch. From the analysis of the experimental results, it was observed that the bioburden range was very wide and consequently the estimated sterilization doses too. If this is the case, the determination of a tissue-specific dose per production batch is necessary to achieve a specified requirement of SAL. Otherwise if the dose of 25 kGy is preselected, a standardized method for substantiation of this dose should be done to confirm the radiation sterilization process.

  5. Vancomycin iontophoresis of allograft bone

    PubMed Central

    Edmondson, M. C.; Day, R.; Wood, D.

    2014-01-01

    Objectives The most concerning infection of allografts and operative procedures is methicillin resistant Staphylococcus aureus (MRSA) and no current iontophoresed antibiotics effectively combat this microbe. It was initially hypothesised that iontophoresis of vancomycin through bone would not be effective due to its large molecular size and lack of charge. The aim of this study was to determine whether this was a viable procedure and to find the optimum conditions for its use. Methods An iontophoresis cell was set up with varying concentrations of Vancomycin within the medulla of a section of sheep tibia, sealed from an external saline solution. The cell was run for varying times, Vancomycin concentrations and voltages, to gain information on optimisation of conditions for impregnating the graft. Each graft was then sectioned and dust ground from the exposed surface. The dust was serially washed to extract the Vancomycin and concentrations measured and plotted for all variables tested. Results Vancomycin was successfully delivered and impregnated to the graft using the iontophoresis technique. The first order fit to the whole data set gave a significant result (p = 0.0233), with a significant concentration (p = 0.02774) component. The time component was the next most significant (p = 0.0597), but did not exceed the 95% confidence level. Conclusions Iontophoresis is an effective method for delivering Vancomycin to allograft bone. The concentrations of the vancomycin solution affected the bone concentration, but results were highly variable. Further study should be done on the effectiveness of delivering different antibiotics using this method. PMID:24729101

  6. BIN1 is Reduced and Cav1.2 Trafficking is Impaired in Human Failing Cardiomyocytes

    PubMed Central

    Hong, Ting-Ting; Smyth, James W.; Chu, Kevin Y.; Vogan, Jacob M.; Fong, Tina S.; Jensen, Brian C.; Fang, Kun; Halushka, Marc K.; Russell, Stuart D.; Colecraft, Henry; Hoopes, Charles W.; Ocorr, Karen; Chi, Neil C.; Shaw, Robin M.

    2011-01-01

    Background Heart failure is a growing epidemic and a typical aspect of heart failure pathophysiology is altered calcium transients. Normal cardiac calcium transients are initiated by Cav1.2 channels at cardiac T-tubules. BIN1 is a membrane scaffolding protein that causes Cav1.2 to traffic to T-tubules in healthy hearts. The mechanisms of Cav1.2 trafficking in heart failure are not known. Objective To study BIN1 expression and its effect on Cav1.2 trafficking in failing hearts. Methods Intact myocardium and freshly isolated cardiomyocytes from non-failing and end-stage failing human hearts were used to study BIN1 expression and Cav1.2 localization. To confirm Cav1.2 surface expression dependence on BIN1, patch clamp recordings were performed of Cav1.2 current in cell lines with and without trafficking competent BIN1. Also, in adult mouse cardiomyocytes, surface Cav1.2 and calcium transients were studied after shRNA mediated knockdown of BIN1. For a functional readout in intact heart, calcium transients and cardiac contractility were analyzed in a zebrafish model with morpholino mediated knockdown of BIN1. Results BIN1 expression is significantly decreased in failing cardiomyocytes at both mRNA (30% down) and protein (36% down) levels. Peripheral Cav1.2 is reduced 42% by imaging and biochemical T-tubule fraction of Cav1.2 is reduced 68%. Total calcium current is reduced 41% in a cell line expressing non-trafficking BIN1 mutant. In mouse cardiomyocytes, BIN1 knockdown decreases surface Cav1.2 and impairs calcium transients. In zebrafish hearts, BIN1 knockdown causes a 75% reduction in calcium transients and severe ventricular contractile dysfunction. Conclusions The data indicate that BIN1 is significantly reduced in human heart failure, and this reduction impairs Cav1.2 trafficking, calcium transients, and contractility. PMID:22138472

  7. Reducing allograft contamination and disease transmission: intraosseous temperatures of femoral head allografts during autoclaving

    PubMed Central

    Ang, Chay-You; Yew, Andy Khye-Soon; Tay, Darren Keng-Jin; Chia, Shi-Lu; Yeo, Seng-Jin; Lo, Ngai-Nung; Chin, Pak-Lin

    2014-01-01

    INTRODUCTION The Singapore General Hospital Bone Bank, which exclusively stores femoral head allografts, relies on flash sterilisation to prevent allograft-related disease transmission and wound infection. However, intraosseous temperatures during autoclaving may be lower than required to eliminate human immunodeficiency virus, and hepatitis B and C viruses. The aim of this study is to determine the intraosseous temperatures of femoral head allografts during autoclaving and to assess the adequacy of autoclaving in preventing disease transmission. METHODS Six femoral heads were acquired from patients who underwent hip arthroplasty. The specimens were divided into two groups. The first group underwent flash sterilisation with a sterilisation time of 4 min, while a longer sterilisation time of 22 min was used for the second group. RESULTS The highest core temperature in the first group was 130°C, while the core temperatures in the second group plateaued at 133°C for all allografts. In the first group, only smaller allografts maintained temperatures sufficient for the inactivation of the clinically relevant viral pathogens. In contrast, all allografts in the second group were terminally sterilised. CONCLUSION There is an inverse correlation between the size of allografts and intraosseous temperatures achieved during autoclaving. Therefore, we recommend dividing large allografts into smaller pieces, in order to achieve intraosseous temperatures adequate for the elimination of transmissible pathogens during flash sterilisation. Allografts should not be terminally sterilised, as the resulting allografts will become unusable. Despite modern processing techniques, stringent donor selection remains vital in the effort to prevent allograft-related infections. Autoclaving is an economical and efficacious method of preventing allograft-related disease transmission. PMID:25631893

  8. Management of digital vasculopathy in systemic sclerosis: benefits of multiple courses of endothelin-1 receptor antagonists

    PubMed Central

    Ngcozana, Tanaka; Ong, Voon; Denton, Christopher Paul

    2014-01-01

    Two patients with scleroderma and recurrent digital ulcers (DUs) were treated with bosentan for 6 months. Treatment was associated with a reduction in the number of new DUs; however, DUs recurred on treatment discontinuation. This case report illustrates the positive response of digital vasculopathy to bosentan and describes the benefits of multiple bosentan treatment courses in these patients. PMID:24682137

  9. [Hand allograft transplantation: what are the implications?].

    PubMed

    Masquelet, Alain Charles

    2013-12-01

    The first hand allograft transplantation was performed in 1998 by a French surgeons team and has opened the era of functional allotransfers. In France, the authorized preliminary study included five patients who sustained traumatic amputation of both hands. All patients had bilateral hand allograft transplantation. Long-term results (follow-up ranging from 3 to 12 years) undoubtedly show a useful daily function, a good psychological acceptance and a physiological integration. Despite several obstacles as the need of immunosuppressive therapy for life, hand allograft transplantation is worthy of interest in some outstanding situations.

  10. Role of Transcranial Doppler in the Evaluation of Vasculopathy in Tuberculous Meningitis

    PubMed Central

    Tai, Mei-Ling Sharon; Sharma, Vijay K.

    2016-01-01

    Background Vascular complications are important causes of cerebral infarction in tuberculous meningitis (TBM).Transcranial Doppler ultrasonography (TCD) is a non-invasive tool that can provide real-time information about cerebral hemodynamics. However, the literature on the role of TCD in the diagnosis or monitoring of vasculopathy associated with TBM is scarce. We explored the role of TCD in the diagnosis and monitoring of TBM-related vasculopathy of the major intracranial arteries. Methods Consecutive patients with TBM admitted to our tertiary center between 2011 and 2015 were included. All patients underwent TCD evaluation within 2 weeks of hospitalisation and it was repeated 2 weeks later. Mean flow velocity (Vmean) and pulsatility index (PI) were recorded. Flow velocities obtained from the submandibular internal carotid artery were also measured to calculate the Lindegaard ratio. A correlation was made between the patients who demonstrated vasculopathy on TCD, and patients with confirmed focal narrowing on computed tomography angiography (CTA) or magnetic resonance angiography (MRA). The modified Rankin scale (mRS) was used to assess the clinical outcome at three and six months. Results A total of 36 patients were recruited. Focally elevated flow velocities in the middle cerebral artery (MCA) were observed in 11 (30.6%) patients, bilaterally in 6 of them. The Lindegaard ratio was elevated (>3) in 10 (90.9%) of them, which occurred as early as the fourth day of hospitalization and persisted as long as four months. Eighty percent of patients with TBM vasculopathy by TCD criteria, also had narrowing on CTA or MRA. Ten patients (27.8%) achieved good outcome (mRS 0–2) at 3 months, which increased to 13 (36.1%) at 6 months. Conclusion A considerable proportion of patients with TBM develops intracranial vasculopathy, which can be reliably diagnosed and monitored using TCD. PMID:27723828

  11. Radiation sterilization of tissue allografts: A review

    PubMed Central

    Singh, Rita; Singh, Durgeshwer; Singh, Antaryami

    2016-01-01

    Tissue substitutes are required in a number of clinical conditions for treatment of injured and diseased tissues. Tissues like bone, skin, amniotic membrane and soft tissues obtained from human donor can be used for repair or reconstruction of the injured part of the body. Allograft tissues from human donor provide an excellent alternative to autografts. However, major concern with the use of allografts is the risk of infectious disease transmission. Therefore, tissue allografts should be sterilized to make them safe for clinical use. Gamma radiation has several advantages and is the most suitable method for sterilization of biological tissues. This review summarizes the use of gamma irradiation technology as an effective method for sterilization of biological tissues and ensuring safety of tissue allografts. PMID:27158422

  12. Renal allograft rejection: sonography and scintigraphy

    SciTech Connect

    Singh, A.; Cohen, W.N.

    1980-07-01

    A total of 30 renal allograft patients who had sonographic B scanning and radionuclide studies of the transplant was studied as to whether: (1) the allograft rejection was associated with any consistent and reliable sonographic features and (2) the sonograms complemented the radionuclide studies. Focal areas of decreased parenchymal echogenicity were the most striking and consistent sonographic finding in chymal echogenicity were the most striking and consistens sonographic finding in allograft rejection. This was observed in most of the patients exhibiting moderate or severe rejection, but was frequently absent with mild rejection. Areas of decreased parenchymal echogenicity were not seen during episodes of acute tubular necrosis. Therefore, sonography showing zones of decreased parenchymal echogenicity was complementary to radionuclide studies in the diagnosis of allograft rejection versus acute tubular necrosis. Corticomedullary demarcation was difficult to interpret because of technical variables, and was inconsistently related to rejection in this series.

  13. Radiation sterilization of tissue allografts: A review.

    PubMed

    Singh, Rita; Singh, Durgeshwer; Singh, Antaryami

    2016-04-28

    Tissue substitutes are required in a number of clinical conditions for treatment of injured and diseased tissues. Tissues like bone, skin, amniotic membrane and soft tissues obtained from human donor can be used for repair or reconstruction of the injured part of the body. Allograft tissues from human donor provide an excellent alternative to autografts. However, major concern with the use of allografts is the risk of infectious disease transmission. Therefore, tissue allografts should be sterilized to make them safe for clinical use. Gamma radiation has several advantages and is the most suitable method for sterilization of biological tissues. This review summarizes the use of gamma irradiation technology as an effective method for sterilization of biological tissues and ensuring safety of tissue allografts.

  14. Zebrafish CaV2.1 Calcium Channels Are Tailored for Fast Synchronous Neuromuscular Transmission

    PubMed Central

    Naranjo, David; Wen, Hua; Brehm, Paul

    2015-01-01

    The CaV2.2 (N-type) and CaV2.1 (P/Q-type) voltage-dependent calcium channels are prevalent throughout the nervous system where they mediate synaptic transmission, but the basis for the selective presence at individual synapses still remains an open question. The CaV2.1 channels have been proposed to respond more effectively to brief action potentials (APs), an idea supported by computational modeling. However, the side-by-side comparison of CaV2.1 and CaV2.2 kinetics in intact neurons failed to reveal differences. As an alternative means for direct functional comparison we expressed zebrafish CaV2.1 and CaV2.2 α-subunits, along with their accessory subunits, in HEK293 cells. HEK cells lack calcium currents, thereby circumventing the need for pharmacological inhibition of mixed calcium channel isoforms present in neurons. HEK cells also have a simplified morphology compared to neurons, which improves voltage control. Our measurements revealed faster kinetics and shallower voltage-dependence of activation and deactivation for CaV2.1. Additionally, recordings of calcium current in response to a command waveform based on the motorneuron AP show, directly, more effective activation of CaV2.1. Analysis of calcium currents associated with the AP waveform indicate an approximately fourfold greater open probability (PO) for CaV2.1. The efficient activation of CaV2.1 channels during APs may contribute to the highly reliable transmission at zebrafish neuromuscular junctions. PMID:25650925

  15. Computational Biology: Modeling Chronic Renal Allograft Injury

    PubMed Central

    Stegall, Mark D.; Borrows, Richard

    2015-01-01

    New approaches are needed to develop more effective interventions to prevent long-term rejection of organ allografts. Computational biology provides a powerful tool to assess the large amount of complex data that is generated in longitudinal studies in this area. This manuscript outlines how our two groups are using mathematical modeling to analyze predictors of graft loss using both clinical and experimental data and how we plan to expand this approach to investigate specific mechanisms of chronic renal allograft injury. PMID:26284070

  16. Bone allografts in reconstructive middle ear surgery.

    PubMed

    Gersdorff, M; Vilain, J; Maisin, J P; Munting, E; Delloye, C

    1989-01-01

    The authors present their current experience with stored bone grafts, using allografts shaped from the cortices of long bones for reconstructing the tympano-ossicular chain. The materials and the methods are described. The anatomical results have been good in 97% of the cases, while the functional results are as satisfactory as those obtained with bioceramics. In addition to ossiculoplasty, the bone allografts can also be used in otology for reconstructing large bony defects of the temporal bone.

  17. Poor wound healing after pial synangiosis in 2 children with moyamoya vasculopathy associated with neurofibromatosis type 1.

    PubMed

    Golomb, Meredith R; Smith, Jodi L

    2014-10-01

    Wound healing is a key component of recovery for children with neurologic conditions undergoing neurosurgical procedures. Understanding factors that can impair wound healing aids in planning long-term clinical care. Children with neurofibromatosis type 1 are at risk for vasculopathies in the brain (including moyamoya vasculopathy) and in other organs, including the heart, lung, and skin. Neurofibromatosis 1 is caused by mutations in the gene for neurofibromin, a protein that plays a role in tissue maintenance and repair as well as tumor suppression. The authors report 2 children with neurofibromatosis 1-associated moyamoya vasculopathy who developed significant wound healing complications after pial synangiosis surgery. They discuss possible contributors to these complications, including the role of neurofibromin and the possibility of vasculopathy affecting the skin, and the implications of poor wound healing in pediatric neurology patients.

  18. CaV1.1: The atypical prototypical voltage-gated Ca2+ channel

    PubMed Central

    Bannister, Roger A.; Beam, Kurt G.

    2012-01-01

    CaV1.1 is the prototype for the other nine known CaV channel isoforms, yet it has functional properties that make it truly atypical of this group. Specifically, CaV1.1 is expressed solely in skeletal muscle where it serves multiple purposes; it is the voltage sensor for excitation-contraction (EC) coupling and it is an L-type Ca2+ channel which contributes to a form of activity-dependent Ca2+ entry that has been termed Excitation-Coupled Ca2+ Entry (ECCE). The ability of CaV1.1 to serve as voltage-sensor for EC coupling appears to be unique amongst CaV channels, whereas the physiological role of its more conventional function as a Ca2+ channel has been a matter of uncertainty for nearly 50 years. In this chapter, we discuss how CaV1.1 supports EC coupling, the possible relevance of Ca2+ entry through CaV1.1 and how alterations of CaV1.1 function can have pathophysiological consequences. PMID:22982493

  19. Bone Allografts: What Is the Risk of Disease Transmission with Bone Allografts?

    MedlinePlus

    ... Safety of Bone Allografts Used in Dentistry: A Review. JADA September 2008 vol. 139 no. 9 1192–1199. Mellonig JT. Donor selection, testing, and inactivation of the HIV virus in freeze-dried bone allografts. Pract Periodontics Aesthet Dent 1995;7:13–22. Mellonig JT, Prewett AB, Moyer ...

  20. Allograft inflammatory factor-1 stimulates chemokine production and induces chemotaxis in human peripheral blood mononuclear cells.

    PubMed

    Kadoya, Masatoshi; Yamamoto, Aihiro; Hamaguchi, Masahide; Obayashi, Hiroshi; Mizushima, Katsura; Ohta, Mitsuhiro; Seno, Takahiro; Oda, Ryo; Fujiwara, Hiroyoshi; Kohno, Masataka; Kawahito, Yutaka

    2014-06-06

    Allograft inflammatory factor-1 (AIF-1) is expressed by macrophages, fibroblasts, endothelial cells and smooth muscle cells in immune-inflammatory disorders such as systemic sclerosis, rheumatoid arthritis and several vasculopathies. However, its molecular function is not fully understood. In this study, we examined gene expression profiles and induction of chemokines in monocytes treated with recombinant human AIF (rhAIF-1). Using the high-density oligonucleotide microarray technique, we compared mRNA expression profiles of rhAIF-1-stimulated CD14(+) peripheral blood mononuclear cells (CD14(+) PBMCs) derived from healthy volunteers. We demonstrated upregulation of genes for several CC chemokines such as CCL1, CCL2, CCL3, CCL7, and CCL20. Next, using ELISAs, we confirmed that rhAIF-1 promoted the secretion of CCL3/MIP-1α and IL-6 by CD14(+) PBMCs, whereas only small amounts of CCL1, CCL2/MCP-1, CCL7/MCP-3 and CCL20/MIP-3α were secreted. Conditioned media from rhAIF-1stimulated CD14(+) PBMCs resulted in migration of PBMCs. These findings suggest that AIF-1, which induced chemokines and enhanced chemotaxis of monocytes, may represent a molecular target for the therapy of immune-inflammatory disorders.

  1. Painless Livedoid Vasculopathy in a Patient with G20210A Prothrombin Gene Mutation.

    PubMed

    Mirrakhimov, Aibek E; Velasquez Kho, Erwin; Ali, Alaa

    2012-01-01

    87 year old Caucasian female with chronic painless non-healing ulcers over malleoli was admitted to the hospital. On a physical examination, there were two bilateral and laterally located malleoli ulcers with no discharge. A thorough work up was done: lower extremities venous and arterial Doppler ultrasound did not show any evidence of venous and arterial disease respectively. Heterozygous G20210A Prothrombin gene mutation was found, and the patient was started on anticoagulation. This case reports highlights a possibility of a painless livedoid vasculopathy presentation in a patient without significant past thrombotic events. Therefore, it is important to consider livedoid vasculopathy in the differential in a patient with painless ulcerative, atrophic and/or nodular skin lesions over the shins and malleoli.

  2. Genetics and Epigenetics of Chronic Allograft Dysfunction in Kidney Transplants.

    PubMed

    Zununi Vahed, Sepideh; Samadi, Nasser; Mostafidi, Elmira; Ardalan, Mohammad Reza; Omidi, Yadollah

    2016-01-01

    Chronic allograft dysfunction is the most common cause of allograft lost. Chronic allograft dysfunction happens as a result of complex interactions at the molecular and cellular levels. Genetic and environmental factors both influence the evolution and progression of the chronic allograft dysfunction. Epigenetic modification could be considered as a therapeutically modifiable element to pause the fibrosis process through novel strategies. In this review, the PubMed database was searched for English-language articles on these new areas.

  3. [Livedoid vasculopathy with heterozygous factor V Leiden mutation and sticky platelet syndrome].

    PubMed

    Lewerenz, V; Burchardt, T; Büchau, A; Ruzicka, T; Megahed, M

    2004-04-01

    A 64-year-old male patient presented with painful ulcerations and livedo racemosa of both lower limbs. He had a history of cerebral and myocardial infarctions. Dermatohistologic findings and laboratory tests of the patient's coagulation system revealed the diagnosis of livedoid vasculopathy with heterozygous factor V Leiden mutation and sticky platelet syndrome type II. Systemic treatment with acetylsalicylic acid and heparin as well as topical therapy with disinfectant and granulation-inducing agents resulted in improvement of the skin lesions.

  4. Livedoid vasculopathy as a marker of systemic disease: report of two cases*

    PubMed Central

    Lima, Raquel Sucupira Andrade; Maquiné, Gustavo Ávila; Talhari, Carolina; Encarnação, Isabel Cristina Lima; Schettini, Antônio Pedro Mendes; Santos, Mônica

    2014-01-01

    The livedoid vasculopathy is an obstructive vascular process of etiology not yet fully known, being possibly associated with several prothrombotic events. It is clinically characterized by the presence of painful and recurring purpuric lesions, which usually suffer ulceration and evolve with formation of white atrophic scars usually located in the lower limbs. Two cases are here reported of painful ulcerated lesions on the lower limbs, in which the identification of VL enabled the diagnosis of systemic diseases. PMID:25184928

  5. Radionuclide surveillance of the allografted pancreas

    SciTech Connect

    George, E.A.; Salimi, Z.; Carney, K.; Castaneda, M.; Garvin, P.J.

    1988-04-01

    To determine the value of scintigraphy to detect posttransplantation complications of the allografted pancreas, we retrospectively reviewed 209 scintigrams obtained with /sup 99m/Tc-sulfur colloid (/sup 99m/Tc-SC) and /sup 99m/Tc-glucoheptonate (/sup 99m/Tc-GH). The scintigraphic studies were performed in 37 recipients of simultaneous renal and pancreatic allografts harvested from the same donor. /sup 99m/Tc-SC was used as an indicator of thrombotic vasculitis; pancreatic perfusion and blood-pool parameters were monitored with /sup 99m/Tc-GH. In 11 of the 37 recipients, scintigraphic abnormalities suggested posttransplantation infarction. Recurrent episodes of acute rejection of the pancreatic allograft, which always coincided with acute rejection of the renal allograft, were monitored in 24 recipients. Rejection-induced ischemic pancreatitis was suggested in 12 of the 24 recipients and persisted in 10 recipients for several weeks after improvement of renal allograft rejection. Pancreatic atrophy was suggested scintigraphically in 16 of the 24 recipients with recurrent episodes of rejection. Spontaneous pancreatic-duct obstruction and obstructive pancreatitis were associated with a scintigraphic pattern similar to that of rejection-induced ischemic pancreatitis. We concluded that the specific radionuclides used in this series are useful for the surveillance and assessment of posttransplantation pancreatic infarction, acute rejection, pancreatitis, and atrophy

  6. Immediate retransplantation for pancreas allograft thrombosis.

    PubMed

    Hollinger, E F; Powelson, J A; Mangus, R S; Kazimi, M M; Taber, T E; Goble, M L; Fridell, J A

    2009-04-01

    Early pancreas allograft failure most commonly results from thrombosis and requires immediate allograft pancreatectomy. Optimal timing for retransplantation remains undefined. Immediate retransplantation facilitates reuse of the same anatomic site before extensive adhesions have formed. Some studies suggest that early retransplantation is associated with a higher incidence of graft loss. This study is a retrospective review of immediate pancreas retransplants performed at a single center. All cases of pancreas allograft loss within 2 weeks were examined. Of 228 pancreas transplants, 12 grafts were lost within 2 weeks of surgery. Eleven of these underwent allograft pancreatectomy for thrombosis. One suffered anoxic brain injury and was not a retransplantation candidate, one was retransplanted at 3.5 months and nine patients underwent retransplantation 1-16 days following the original transplant. Of the nine early retransplants, one pancreas was lost to heparin-induced thrombocytopenia, one recipient died with function at 2.9 years and the other grafts continue to function at 76-1137 days (mean 572 days). One-year graft survival for early retransplantation was 89% compared to 91% for all pancreas transplants at our center. Immediate retransplantation following pancreatic graft thrombosis restores durable allograft function with outcomes comparable to first-time pancreas transplantation.

  7. [Case of lupus vasculopathy associated with lupus nephritis class IV-G (A)].

    PubMed

    Eguchi, Eriko; Shimazu, Keiji; Takaori, Kouji; Nishiguchi, Kensuke; Mori, Keita; Yorifuji, Soushi; Murakami, Toru; Koshikawa, Masao; Tanaka, Atsuo; Kuwahara, Takashi

    2010-01-01

    Various renal vascular lesions are complicated with systemic lupus erythematosus (SLE), and are often overlooked in the actual renal biopsy specimen. We report a case of biopsy-proven lupus vasculopathy, with lupus nephritis class IV-G (A). She developed SLE at 15 years of age, and was treated with prednisolone(PSL) and cyclophosphamide (CTX). Sometimes she experienced a flare-up clinically or serologically, requiring a dose increase of oral PSL. At 40 years of age, she visited our hospital after discontinuation of hospital visits for about 4 months. Oral PSL at 30 mg per day was not effective for urinary abnormalities, increase of anti double-stranded DNA (ds-DNA) antibody titer and decrease in complement components. On admission she had hypertension (180/92 mmHg) and signs of microangiopathic hemolytic anemia. Renal biopsy findings showed the glomerular changes of lupus nephritis, WHO class IV-G (A), and lupus vasculopathy, which is marked luminal narrowing or total occlusion by abundant subendothelial accumulation of immunoglobulins and complement components. In addition to PSL, intravenous pulse CTX promptly achieved clinical remission. When lupus vasculopathy is complicated, CTX may be useful.

  8. Tocilizumab reverses cerebral vasculopathy in a patient with homozygous SAMHD1 mutation.

    PubMed

    Henrickson, Michael; Wang, Heng

    2017-03-13

    An auto-inflammatory syndrome consequent to SAMHD1 mutations involves cerebral vasculopathy characterized by multifocal stenosis and aneurysms within large arteries, moyamoya, chronic ischemia, and early-onset strokes (SAMS). While this condition involves the innate immune system, additional clinical features mimic systemic lupus erythematosus. Mutations in this gene can also cause a subset of the rare genetic condition Aicardi-Goutières syndrome. To date, no established therapy successfully prevents disease progression. We report a corticosteroid-dependent SAMS patient, a 19-year-old male of Old Order Amish ancestry, with diffuse cerebral arteriopathy identified through contrast brain magnetic resonance arteriography (MRA) and MRI. He received subcutaneous adalimumab every 2 weeks for 9 months with minimal response. Then, he started intravenous tocilizumab (6 mg/kg/dose) every 4 weeks. He sustained steadily normalizing cerebral vasculopathy and lab abnormalities resolved, allowing prednisone reduction. We conclude that the cerebral vasculopathy of the homozygous SAMHD1 mutation-mediated auto-inflammatory disease SAMS responded favorably to tocilizumab infusion therapy.

  9. Glycyrrhizin Ameliorates Fibrosis, Vasculopathy, and Inflammation in Animal Models of Systemic Sclerosis

    PubMed Central

    Yamashita, Takashi; Asano, Yoshihide; Taniguchi, Takashi; Nakamura, Kouki; Saigusa, Ryosuke; Miura, Shunsuke; Toyama, Tetsuo; Takahashi, Takehiro; Ichimura, Yohei; Yoshizaki, Ayumi; Trojanowska, Maria; Sato, Shinichi

    2017-01-01

    Systemic sclerosis (SSc) is a multisystem inflammatory and vascular disease resulting in extensive tissue fibrosis. Glycyrrhizin, clinically used for chronic hepatic diseases and itching dermatitis, modulates the pathological processes of inflammation, vasculopathy, and fibrosis in human diseases and their animal models. Therefore, we investigated a potential impact of glycyrrhizin on the key pathological manifestations of SSc, including inflammation, vasculopathy, and tissue fibrosis, with bleomycin-treated mice mimicking the fibrotic and inflammatory components of SSc and endothelial cell-specific Fli1-knockout mice recapitulating SSc vasculopathy. Glycyrrhizin significantly ameliorated dermal fibrosis in bleomycin-treated mice, which was partly attributable to blockade of transforming growth factor-β signaling in dermal fibroblasts through the downregulation of thrombospondin 1, a latent transforming growth factor-β receptor, and transcription factors Smad3 and Ets1. Furthermore, bleomycin-dependent induction of T helper type 2-skewed immune polarization, M2 macrophage infiltration, and endothelial-to-mesenchymal transition were greatly suppressed in mice administered glycyrrhizin. Glycyrrhizin also improved vascular permeability of endothelial cell-specific Fli1-knockout mice by increasing the expression of molecules regulating vascular integrity. These results indicate that glycyrrhizin ameliorates bleomycin-induced dermal fibrosis through the inhibition of fibroblast activation, T helper type 2-skewed immune polarization, M2 macrophage infiltration, and endothelial-to-mesenchymal transition and improves endothelial Fli1 deficiency-dependent vascular disintegrity, implying its potential as a disease-modifying drug for SSc. PMID:27777101

  10. Bone allografts: What they can offer and what they cannot.

    PubMed

    Delloye, C; Cornu, O; Druez, V; Barbier, O

    2007-05-01

    Bone allografts can be used in any kind of surgery involving bone from minor defects to major bone loss after tumour resection. This review describes the various types of bone grafts and the current knowledge on bone allografts, from procurement and preparation to implantation. The surgical conditions for optimising the incorporation of bone are outlined, and surgeon expectations from a bone allograft discussed.

  11. Renal allograft eosinophilia: An unusual presentation of sudden graft dysfunction

    PubMed Central

    Yuvaraj, A.; Ghosh, S.; Abraham, G.; Koshy, P.

    2017-01-01

    We present a case of sudden allograft dysfunction 11 months after renal transplantation which presented as severe peripheral and allograft eosinophilia and was managed as a case of an acute cellular rejection with significant interstitial graft eosinophilic infiltration. Patient had partial response to antirejection therapy and eventually ended up in a chronic allograft dysfunction. PMID:28356665

  12. T Cell Receptor Mediated Calcium Entry Requires Alternatively Spliced Cav1.1 Channels.

    PubMed

    Matza, Didi; Badou, Abdallah; Klemic, Kathryn G; Stein, Judith; Govindarajulu, Usha; Nadler, Monica J; Kinet, Jean-Pierre; Peled, Amnon; Shapira, Oz M; Kaczmarek, Leonard K; Flavell, Richard A

    2016-01-01

    The process of calcium entry in T cells is a multichannel and multi-step process. We have studied the requirement for L-type calcium channels (Cav1.1) α1S subunits during calcium entry after TCR stimulation. High expression levels of Cav1.1 channels were detected in activated T cells. Sequencing and cloning of Cav1.1 channel cDNA from T cells revealed that a single splice variant is expressed. This variant lacks exon 29, which encodes the linker region adjacent to the voltage sensor, but contains five new N-terminal exons that substitute for exons 1 and 2, which are found in the Cav1.1 muscle counterpart. Overexpression studies using cloned T cell Cav1.1 in 293HEK cells (that lack TCR) suggest that the gating of these channels was altered. Knockdown of Cav1.1 channels in T cells abrogated calcium entry after TCR stimulation, suggesting that Cav1.1 channels are controlled by TCR signaling.

  13. T Cell Receptor Mediated Calcium Entry Requires Alternatively Spliced Cav1.1 Channels

    PubMed Central

    Matza, Didi; Badou, Abdallah; Klemic, Kathryn G.; Stein, Judith; Govindarajulu, Usha; Nadler, Monica J.; Kinet, Jean-Pierre; Peled, Amnon; Shapira, Oz M.; Kaczmarek, Leonard K.; Flavell, Richard A.

    2016-01-01

    The process of calcium entry in T cells is a multichannel and multi-step process. We have studied the requirement for L-type calcium channels (Cav1.1) α1S subunits during calcium entry after TCR stimulation. High expression levels of Cav1.1 channels were detected in activated T cells. Sequencing and cloning of Cav1.1 channel cDNA from T cells revealed that a single splice variant is expressed. This variant lacks exon 29, which encodes the linker region adjacent to the voltage sensor, but contains five new N-terminal exons that substitute for exons 1 and 2, which are found in the Cav1.1 muscle counterpart. Overexpression studies using cloned T cell Cav1.1 in 293HEK cells (that lack TCR) suggest that the gating of these channels was altered. Knockdown of Cav1.1 channels in T cells abrogated calcium entry after TCR stimulation, suggesting that Cav1.1 channels are controlled by TCR signaling. PMID:26815481

  14. The Cavβ1a subunit regulates gene expression and suppresses myogenin in muscle progenitor cells.

    PubMed

    Taylor, Jackson; Pereyra, Andrea; Zhang, Tan; Messi, Maria Laura; Wang, Zhong-Min; Hereñú, Claudia; Kuan, Pei-Fen; Delbono, Osvaldo

    2014-06-23

    Voltage-gated calcium channel (Cav) β subunits are auxiliary subunits to Cavs. Recent reports show Cavβ subunits may enter the nucleus and suggest a role in transcriptional regulation, but the physiological relevance of this localization remains unclear. We sought to define the nuclear function of Cavβ in muscle progenitor cells (MPCs). We found that Cavβ1a is expressed in proliferating MPCs, before expression of the calcium conducting subunit Cav1.1, and enters the nucleus. Loss of Cavβ1a expression impaired MPC expansion in vitro and in vivo and caused widespread changes in global gene expression, including up-regulation of myogenin. Additionally, we found that Cavβ1a localizes to the promoter region of a number of genes, preferentially at noncanonical (NC) E-box sites. Cavβ1a binds to a region of the Myog promoter containing an NC E-box, suggesting a mechanism for inhibition of myogenin gene expression. This work indicates that Cavβ1a acts as a Cav-independent regulator of gene expression in MPCs, and is required for their normal expansion during myogenic development.

  15. The Cavβ1a subunit regulates gene expression and suppresses myogenin in muscle progenitor cells

    PubMed Central

    Taylor, Jackson; Pereyra, Andrea; Zhang, Tan; Messi, Maria Laura; Wang, Zhong-Min; Hereñú, Claudia; Kuan, Pei-Fen

    2014-01-01

    Voltage-gated calcium channel (Cav) β subunits are auxiliary subunits to Cavs. Recent reports show Cavβ subunits may enter the nucleus and suggest a role in transcriptional regulation, but the physiological relevance of this localization remains unclear. We sought to define the nuclear function of Cavβ in muscle progenitor cells (MPCs). We found that Cavβ1a is expressed in proliferating MPCs, before expression of the calcium conducting subunit Cav1.1, and enters the nucleus. Loss of Cavβ1a expression impaired MPC expansion in vitro and in vivo and caused widespread changes in global gene expression, including up-regulation of myogenin. Additionally, we found that Cavβ1a localizes to the promoter region of a number of genes, preferentially at noncanonical (NC) E-box sites. Cavβ1a binds to a region of the Myog promoter containing an NC E-box, suggesting a mechanism for inhibition of myogenin gene expression. This work indicates that Cavβ1a acts as a Cav-independent regulator of gene expression in MPCs, and is required for their normal expansion during myogenic development. PMID:24934157

  16. Environmental perspectives of Phragmites australis (Cav.) Trin. Ex. Steudel

    NASA Astrophysics Data System (ADS)

    Srivastava, Jatin; Kalra, Swinder J. S.; Naraian, Ram

    2014-09-01

    Extensive research is being conducted worldwide to find alternative and efficient systems to lessen the impacts of climate change and reduce environmental pollution. The genus Phragmites has proven ability to mitigate the environmental pollution of its surroundings. Common reed ( Phragmites australis (Cav.) Trin. Ex. Steudel), a graminaceous plant of cosmopolitan nature, has been extensively studied especially for the mitigation of environmental contamination. The capability of common reed to grow well at extreme environmental conditions such as elevated CO2 and high temperature is conferred by several factors such as change of carbon trapping mechanism (from C3 to C4 and vice versa), microbial association and biochemical adaptations. P. australis has been a most preferred unique plant system, especially in ecological engineering for improving the quality of wastewater. This paper reviews the current state of knowledge regarding the suitability of Phragmites australis for environmental remediation and summarizes recent advancements in our understanding of this grass.

  17. Optimization and Implementation of Long Nerve Allografts

    DTIC Science & Technology

    2013-03-01

    mimics the production of the human nerve allograft product used clinically. This includes detergent decellularization , treatment with...is  on  schedule.     The  early  Milestone  to  obtain  ACURO  approval  for   animal  use  was  accomplished...months  1-­‐6):       Task  1a.    Collect,  process  ( decellularize )  and  prepare  7  cm  acellular  allografts

  18. Aneurysmal vasculopathy in human-acquired immunodeficiency virus-infected adults: Imaging case series and review of the literature

    PubMed Central

    Nayak, Nikhil R; Pisapia, Jared M; Petrov, Dmitriy; Pukenas, Bryan A; Hurst, Robert W; Smith, Michelle J

    2015-01-01

    Background Intracranial vasculopathy in adult patients with human-acquired immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) is a rare but increasingly recognized disease entity. Objective We aimed to contribute to and summarize the adult literature describing patients with HIV/AIDS who have intracranial vasculopathy. Methods A retrospective review of adult patients with HIV/AIDS undergoing diagnostic cerebral angiography at our institution from 2007–2013 was performed. A literature review of relevant existing studies was performed. Results Five adult patients with HIV-related aneurysmal and occlusive vasculopathy were diagnosed and/or treated at our institution. A comprehensive review of the literature yielded data from 17 series describing 28 adult patients with HIV/AIDS and intracranial vasculopathy. Our review suggests that low CD4 count, motor weakness, and meningismus may be associated with the sequelae of intracranial vasculopathy/vasculitis in patients with HIV/AIDS. Conclusion Patients with HIV/AIDS who have aneurysmal and stenotic vascular disease may benefit from earlier surveillance with the onset of neurological symptoms. The roles of medical, open surgical, and endovascular therapy in this unique entity will be further defined as the pathological basis of the disease is better understood. PMID:26023074

  19. Molecular epidemiology of chicken anemia virus (CAV) in southeastern Chinese live birds markets.

    PubMed

    Ducatez, M F; Chen, H; Guan, Y; Muller, C P

    2008-03-01

    Between January 2004 and December 2005, cloacal swabs from essentially healthy chickens and silky chickens from live birds markets in Guangdong and Hunan provinces in southeastern China were screened for chicken anemia virus (CAV) by polymerase chain reaction. Phylogenetic analysis of the major structural protein VP1 sequences showed no clear genotype cluster and no correlation with the geographic origin of CAV strains. Virus evolution at the amino acid level was very slow, which corresponds to a strong negative selection of the VP1 gene in China and worldwide. A high proportion (87%) of birds was CAV positive, suggesting that many farms in the region were infected. Further investigations are necessary to evaluate the economic losses caused by CAV and the cost-benefit of vaccination.

  20. Classification of ASASSN-17dj (AT2017cav) with the Liverpool Telescope

    NASA Astrophysics Data System (ADS)

    Bersier, David

    2017-03-01

    We obtained a spectrum of the candidate supernova ASASSN-17dj/AT 2017cav (ATEL #10155) with the SPRAT spectrograph mounted on the robotic 2m Liverpool Telescope at the Roque de los Muchachos observatory (La Palma).

  1. DEMONSTRATION BULLETIN: CAV-OX ULTRAVIOLET OXIDATION PROCESS MAGNUM WATER TECHNOLOGY

    EPA Science Inventory

    The CAV-OX® technology (see Fig- ure 1) destroys organic contaminants, including chlorinated hy- drocarbons, in water. The process uses hydrogen peroxide, hy- drodynamic cavitation, and ultraviolet (UV) radiation to photolyze and oxidize organic compounds present in water at ...

  2. Human native Cav1 channels in chromaffin cells: contribution to exocytosis and firing of spontaneous action potentials.

    PubMed

    Hernández-Vivanco, Alicia; Sanz-Lázaro, Sara; Jiménez-Pompa, Amanda; García-Magro, Nuria; Carmona-Hidalgo, Beatriz; Pérez-Alvarez, Alberto; Caba-González, Jose Carlos; Tabernero, Angel; Alonso Y Gregorio, Sergio; Passas, Juan; Blázquez, Jesús; González-Enguita, Carmen; de Castro-Guerín, Cristina; Albillos, Almudena

    2017-02-05

    The present study was performed to evaluate the Cav1 channel subtypes expressed in human chromaffin cells and the role that these channels play in exocytosis and cell excitability. Here we show that human chromaffin cells obtained from organ donors express Cav1.2 and Cav1.3 subtypes using molecular and pharmacological techniques. Immunocytochemical data demonstrated the presence of Cav1.2 and Cav1.3 subtypes, but not Cav1.1 or Cav1.4. Electrophysiological experiments were conducted to investigate the contribution of Cav1 channels to the exocytotic process and cell excitability. Cav1 channels contribute to the exocytosis of secretory vesicles, evidenced by the block of 3μM nifedipine (36.5±2%) of membrane capacitance increment elicited by 200ms depolarizing pulses. These channels show a minor contribution to the initiation of spontaneous action potential firing, as shown by the 2.5 pA of current at the threshold potential (-34mV), which elicits 10.4mV of potential increment. In addition, we found that only 8% of human chromaffin cells exhibit spontaneous action potentials. These data offer novel information regarding human chromaffin cells and the role of human native Cav1 channels in exocytosis and cell excitability.

  3. CaV3.2 Channels and the Induction of Negative Feedback in Cerebral Arteries

    PubMed Central

    Harraz, Osama F.; Abd El-Rahman, Rasha R.; Bigdely-Shamloo, Kamran; Wilson, Sean M.; Brett, Suzanne E.; Romero, Monica; Gonzales, Albert L.; Earley, Scott; Vigmond, Edward J.; Nygren, Anders; Menon, Bijoy K.; Mufti, Rania E.; Watson, Tim; Starreveld, Yves; Furstenhaupt, Tobias; Muellerleile, Philip R.; Kurjiaka, David T.; Kyle, Barry D.; Braun, Andrew P.; Welsh, Donald G.

    2015-01-01

    Rationale T-type (CaV3.1/CaV3.2) Ca2+ channels are expressed in rat cerebral arterial smooth muscle. Although present, their functional significance remains uncertain with findings pointing to a variety of roles. Objective This study tested whether CaV3.2 channels mediate a negative feedback response by triggering Ca2+ sparks, discrete events that initiate arterial hyperpolarization by activating large-conductance Ca2+-activated K+ channels. Methods and Results Micromolar Ni2+, an agent that selectively blocks CaV3.2 but not CaV1.2/CaV3.1, was first shown to depolarize/constrict pressurized rat cerebral arteries; no effect was observed in CaV3.2−/− arteries. Structural analysis using 3-dimensional tomography, immunolabeling, and a proximity ligation assay next revealed the existence of microdomains in cerebral arterial smooth muscle which comprised sarcoplasmic reticulum and caveolae. Within these discrete structures, CaV3.2 and ryanodine receptor resided in close apposition to one another. Computational modeling revealed that Ca2+ influx through CaV3.2 could repetitively activate ryanodine receptor, inducing discrete Ca2+-induced Ca2+ release events in a voltage-dependent manner. In keeping with theoretical observations, rapid Ca2+ imaging and perforated patch clamp electrophysiology demonstrated that Ni2+ suppressed Ca2+ sparks and consequently spontaneous transient outward K+ currents, large-conductance Ca2+-activated K+ channel mediated events. Additional functional work on pressurized arteries noted that paxilline, a large-conductance Ca2+-activated K+ channel inhibitor, elicited arterial constriction equivalent, and not additive, to Ni2+. Key experiments on human cerebral arteries indicate that CaV3.2 is present and drives a comparable response to moderate constriction. Conclusions These findings indicate for the first time that CaV3.2 channels localize to discrete microdomains and drive ryanodine receptor–mediated Ca2+ sparks, enabling large

  4. Protein kinase A modulation of CaV1.4 calcium channels

    PubMed Central

    Sang, Lingjie; Dick, Ivy E.; Yue, David T.

    2016-01-01

    The regulation of L-type Ca2+ channels by protein kinase A (PKA) represents a crucial element within cardiac, skeletal muscle and neurological systems. Although much work has been done to understand this regulation in cardiac CaV1.2 Ca2+ channels, relatively little is known about the closely related CaV1.4 L-type Ca2+ channels, which feature prominently in the visual system. Here we find that CaV1.4 channels are indeed modulated by PKA phosphorylation within the inhibitor of Ca2+-dependent inactivation (ICDI) motif. Phosphorylation of this region promotes the occupancy of calmodulin on the channel, thus increasing channel open probability (PO) and Ca2+-dependent inactivation. Although this interaction seems specific to CaV1.4 channels, introduction of ICDI1.4 to CaV1.3 or CaV1.2 channels endows these channels with a form of PKA modulation, previously unobserved in heterologous systems. Thus, this mechanism may not only play an important role in the visual system but may be generalizable across the L-type channel family. PMID:27456671

  5. Protein kinase A modulation of CaV1.4 calcium channels

    NASA Astrophysics Data System (ADS)

    Sang, Lingjie; Dick, Ivy E.; Yue, David T.

    2016-07-01

    The regulation of L-type Ca2+ channels by protein kinase A (PKA) represents a crucial element within cardiac, skeletal muscle and neurological systems. Although much work has been done to understand this regulation in cardiac CaV1.2 Ca2+ channels, relatively little is known about the closely related CaV1.4 L-type Ca2+ channels, which feature prominently in the visual system. Here we find that CaV1.4 channels are indeed modulated by PKA phosphorylation within the inhibitor of Ca2+-dependent inactivation (ICDI) motif. Phosphorylation of this region promotes the occupancy of calmodulin on the channel, thus increasing channel open probability (PO) and Ca2+-dependent inactivation. Although this interaction seems specific to CaV1.4 channels, introduction of ICDI1.4 to CaV1.3 or CaV1.2 channels endows these channels with a form of PKA modulation, previously unobserved in heterologous systems. Thus, this mechanism may not only play an important role in the visual system but may be generalizable across the L-type channel family.

  6. Treatment of polypoidal choroidal vasculopathy by photodynamic therapy, aflibercept and dexamethasone triple therapy

    PubMed Central

    Ho, Mary; Woo, Donald C. F.; Chan, Vesta C. K.; Young, Alvin L.; Brelen, Marten E.

    2016-01-01

    Polypoidal choroidal vasculopathy is a relatively common type of degenerative macular disease among the Chinese population. This study aims to describe the therapeutic responses to combination therapy with photodynamic therapy, intravitreal aflibercept and intravitreal dexamethasone in patients with polypoidal choroidal vasculopathy. A prospective series of 17 eyes of 13 patients suffering from treatment-naïve polypoidal choroidal vasculoapathy were recruited. All cases received triple therapy with photodynamic therapy, intravitreal aflibercept and intravitreal dexamethasone and one year outcomes were reported. The baseline visual acuity was 0.65logMAR +/− 0.38 (Snellen 20/80 to 20/100). The visual acuity at 1 week, 3 months, 6 months and one year after treatment were significantly improved to 0.522logMAR+/− 0.365 (P < 0.04) (Snellen 20/70), 0.363logMAR+/−0.382 (Snellen 20/50;P < 0.001), 0.377logMAR +/− 0.440 (Snellen 20/50;p = 0.005), and 0.35logMAR +/− 0.407 (Snellen 20/40;P < 0.001), respectively. The baseline central foveal thickness (CFT) on optical coherence tomography (OCT) was 394.7 +/− 70.6 μm. CFT at 6 months and 1 year after treatment were significantly reduced to 259 +/− 54 μm (p = 0.004) and 271 +/− 49.7 μm(p = 0.016), respectively. Triple therapy with photodynamic therapy, intravitreal aflibercept and intravitreal dexamethasone is an effective treatment for polypoidal choroidal vasculopathy. The majority of cases responded well with significant responses observed as early as 1 week after initiation of therapy. PMID:27848983

  7. Pericytes Derived from Adipose-Derived Stem Cells Protect against Retinal Vasculopathy

    PubMed Central

    Mendel, Thomas A.; Clabough, Erin B. D.; Kao, David S.; Demidova-Rice, Tatiana N.; Durham, Jennifer T.; Zotter, Brendan C.; Seaman, Scott A.; Cronk, Stephen M.; Rakoczy, Elizabeth P.; Katz, Adam J.; Herman, Ira M.; Peirce, Shayn M.; Yates, Paul A.

    2013-01-01

    Background Retinal vasculopathies, including diabetic retinopathy (DR), threaten the vision of over 100 million people. Retinal pericytes are critical for microvascular control, supporting retinal endothelial cells via direct contact and paracrine mechanisms. With pericyte death or loss, endothelial dysfunction ensues, resulting in hypoxic insult, pathologic angiogenesis, and ultimately blindness. Adipose-derived stem cells (ASCs) differentiate into pericytes, suggesting they may be useful as a protective and regenerative cellular therapy for retinal vascular disease. In this study, we examine the ability of ASCs to differentiate into pericytes that can stabilize retinal vessels in multiple pre-clinical models of retinal vasculopathy. Methodology/Principal Findings We found that ASCs express pericyte-specific markers in vitro. When injected intravitreally into the murine eye subjected to oxygen-induced retinopathy (OIR), ASCs were capable of migrating to and integrating with the retinal vasculature. Integrated ASCs maintained marker expression and pericyte-like morphology in vivo for at least 2 months. ASCs injected after OIR vessel destabilization and ablation enhanced vessel regrowth (16% reduction in avascular area). ASCs injected intravitreally before OIR vessel destabilization prevented retinal capillary dropout (53% reduction). Treatment of ASCs with transforming growth factor beta (TGF-β1) enhanced hASC pericyte function, in a manner similar to native retinal pericytes, with increased marker expression of smooth muscle actin, cellular contractility, endothelial stabilization, and microvascular protection in OIR. Finally, injected ASCs prevented capillary loss in the diabetic retinopathic Akimba mouse (79% reduction 2 months after injection). Conclusions/Significance ASC-derived pericytes can integrate with retinal vasculature, adopting both pericyte morphology and marker expression, and provide functional vascular protection in multiple murine models of

  8. Septic vasculitis and vasculopathy in some infectious emergencies: the perspective of the histopathologist.

    PubMed

    Tomasini, C

    2015-02-01

    Sepsis is a potentially life-threatening complication of an infection where cutaneous lesions often represent one of the early signs. A myriad of microorganisms including bacteria, fungi, yeasts, viruses, protozoas, helminths and algae can be implicated. A broad spectrum of clinical and histopathologic findings can be observed in the skin and the common denominator is a thrombotic vasculopathy. The pathogenesis of cutaneous septic vasculitis (SV)/vasculopathy is complex and includes five main mechanisms: disseminated intravascular coagulation, direct invasion and occlusion of blood vessel walls by microorganisms, hypersensitivity reaction with immune complex deposition into blood vessel walls, embolism from a distant infectious site and vascular effects of toxins. Herein we describe the clinicopathologic findings of some selected cases of SV recently observed in our hospital, including purpura fulminans, necrotizing fasciitis, cutaneous meningococcemia, malignant syphilis and disseminated alternaria infection. Histopathologically, a wide spectrum of histopathologic changes was observed in skin specimens from the various entities, involving the intensity and composition of the inflammatory infiltrate, the degree of vascular changes and the presence of microorganisms, that ranged from a predominant not inflammatory, thrombotic-occlusive vasculopathy in purpura fulminans to leukocytoclastic vasculitis like changes in cutaneous meningococcemia to a dermal angiomatosis-like pattern in disseminated Alternaria infection. The different pathologic presentations may be related to the microorganism involved, the main pathogenetic mechanism that induced the vascular injury and the individual immunologic burden. Early skin biopsy for histopathologic examination and microbiologic culture is a cornerstone in the diagnosis of life-threatening diseases that present with cutaneous septic vasculitis. Ancillary techniques, such as immunohistochemistry and polymerase chain reaction are

  9. H2S- and NO-Signaling Pathways in Alzheimer's Amyloid Vasculopathy: Synergism or Antagonism?

    PubMed Central

    Salmina, Alla B.; Komleva, Yulia K.; Szijártó, István A.; Gorina, Yana V.; Lopatina, Olga L.; Gertsog, Galina E.; Filipovic, Milos R.; Gollasch, Maik

    2015-01-01

    Alzheimer's type of neurodegeneration dramatically affects H2S and NO synthesis and interactions in the brain, which results in dysregulated vasomotor function, brain tissue hypoperfusion and hypoxia, development of perivascular inflammation, promotion of Aβ deposition, and impairment of neurogenesis/angiogenesis. H2S- and NO-signaling pathways have been described to offer protection against Alzheimer's amyloid vasculopathy and neurodegeneration. This review describes recent developments of the increasing relevance of H2S and NO in Alzheimer's disease (AD). More studies are however needed to fully determine their potential use as therapeutic targets in Alzheimer's and other forms of vascular dementia. PMID:26696896

  10. Spectral-Domain Optical Coherence Tomography of Polypoidal Choroidal Vasculopathy Associated With Benign Choroidal Nevus.

    PubMed

    De Salvo, Gabriella; Vaz-Pereira, Sara; Sehmi, Kulwant S; Andrews, Richard M; Sagoo, Mandeep S

    2015-01-01

    Two cases of polypoidal choroidal vasculopathy (PCV) complicating benign choroidal nevus and their tomographic features at spectral-domain optical coherence tomography (SD-OCT) are reported. Two eyes with choroidal nevus and associated subretinal fluid underwent complete ophthalmological examination, SD-OCT, fundus fluorescein angiography, and indocyanine green angiography (ICGA). SD-OCT and ICGA confirmed the diagnosis of PCV in both cases. Ophthalmologists should be aware of this rare combination between choroidal nevus and PCV. If a choroidal nevus presents with subretinal fluid, this does not always herald malignant transformation, and PCV should be ruled out so that the correct treatment can be planned.

  11. Composition and Antidiarrheal Activity of Bidens odorata Cav.

    PubMed Central

    Zavala-Mendoza, Daniel; Alarcon-Aguilar, Francisco J.; Pérez-Gutierrez, Salud; Escobar-Villanueva, M. Carmen; Zavala-Sánchez, Miguel A.

    2013-01-01

    The antidiarrheal effects of chloroform, methanol, and aqueous extracts of Bidens odorata Cav. were investigated at doses of 200 mg/kg on castor-oil-induced diarrhea. The chloroform extract of B. odorata (CBO) reduced diarrhea by 72.72%. The effect of CBO was evaluated on mice with diarrhea induced by castor oil, MgSO4, arachidonic acid, or prostaglandin E2. CBO inhibited the contraction induced by carbachol chloride on ileum (100 µg/mL) and intestinal transit (200 mg/kg) in Wistar rats. The active fraction of CBO (F4) at doses of 100 mg/kg inhibited the diarrhea induced by castor oil (90.1%) or arachidonic acid (72.9%) but did not inhibit the diarrhea induced by PGE2. The active fraction of F4 (FR5) only was tested on diarrhea induced with castor oil and inhibited this diarrhea by 92.1%. The compositions of F4 and FR5 were determined by GC-MS, and oleic, palmitic, linoleic, and stearic acids were found. F4 and a mixture of the four fatty acids inhibited diarrhea at doses of 100 mg/kg (90.1% and 70.6%, resp.). The results of this study show that B. odorata has antidiarrheal effects, as is claimed by folk medicine, and could possibly be used for the production of a phytomedicine. PMID:24282432

  12. CaV channels and cancer: canonical functions indicate benefits of repurposed drugs as cancer therapeutics.

    PubMed

    Buchanan, Paul J; McCloskey, Karen D

    2016-10-01

    The importance of ion channels in the hallmarks of many cancers is increasingly recognised. This article reviews current knowledge of the expression of members of the voltage-gated calcium channel family (CaV) in cancer at the gene and protein level and discusses their potential functional roles. The ten members of the CaV channel family are classified according to expression of their pore-forming α-subunit; moreover, co-expression of accessory α2δ, β and γ confers a spectrum of biophysical characteristics including voltage dependence of activation and inactivation, current amplitude and activation/inactivation kinetics. CaV channels have traditionally been studied in excitable cells including neurones, smooth muscle, skeletal muscle and cardiac cells, and drugs targeting the channels are used in the treatment of hypertension and epilepsy. There is emerging evidence that several CaV channels are differentially expressed in cancer cells compared to their normal counterparts. Interestingly, a number of CaV channels also have non-canonical functions and are involved in transcriptional regulation of the expression of other proteins including potassium channels. Pharmacological studies show that CaV canonical function contributes to the fundamental biology of proliferation, cell-cycle progression and apoptosis. This raises the intriguing possibility that calcium channel blockers, approved for the treatment of other conditions, could be repurposed to treat particular cancers. Further research will reveal the full extent of both the canonical and non-canonical functions of CaV channels in cancer and whether calcium channel blockers are beneficial in cancer treatment.

  13. Cav1.1 controls frequency-dependent events regulating adult skeletal muscle plasticity.

    PubMed

    Jorquera, Gonzalo; Altamirano, Francisco; Contreras-Ferrat, Ariel; Almarza, Gonzalo; Buvinic, Sonja; Jacquemond, Vincent; Jaimovich, Enrique; Casas, Mariana

    2013-03-01

    An important pending question in neuromuscular biology is how skeletal muscle cells decipher the stimulation pattern coming from motoneurons to define their phenotype as slow or fast twitch muscle fibers. We have previously shown that voltage-gated L-type calcium channel (Cav1.1) acts as a voltage sensor for activation of inositol (1,4,5)-trisphosphate [Ins(1,4,5)P₃]-dependent Ca(2+) signals that regulates gene expression. ATP released by muscle cells after electrical stimulation through pannexin-1 channels plays a key role in this process. We show now that stimulation frequency determines both ATP release and Ins(1,4,5)P₃ production in adult skeletal muscle and that Cav1.1 and pannexin-1 colocalize in the transverse tubules. Both ATP release and increased Ins(1,4,5)P₃ was seen in flexor digitorum brevis fibers stimulated with 270 pulses at 20 Hz, but not at 90 Hz. 20 Hz stimulation induced transcriptional changes related to fast-to-slow muscle fiber phenotype transition that required ATP release. Addition of 30 µM ATP to fibers induced the same transcriptional changes observed after 20 Hz stimulation. Myotubes lacking the Cav1.1-α1 subunit released almost no ATP after electrical stimulation, showing that Cav1.1 has a central role in this process. In adult muscle fibers, ATP release and the transcriptional changes produced by 20 Hz stimulation were blocked by both the Cav1.1 antagonist nifedipine (25 µM) and by the Cav1.1 agonist (-)S-BayK 8644 (10 µM). We propose a new role for Cav1.1, independent of its calcium channel activity, in the activation of signaling pathways allowing muscle fibers to decipher the frequency of electrical stimulation and to activate specific transcriptional programs that define their phenotype.

  14. Aβ immunotherapy for Alzheimer's disease: effects on apoE and cerebral vasculopathy.

    PubMed

    Sakai, Kenji; Boche, Delphine; Carare, Roxana; Johnston, David; Holmes, Clive; Love, Seth; Nicoll, James A R

    2014-12-01

    Aβ immunotherapy for Alzheimer's disease (AD) results in the removal of Aβ plaques and increased cerebral amyloid angiopathy (CAA). In current clinical trials, amyloid-related imaging abnormalities (ARIAs), putatively due to exacerbation of CAA, are concerning side effects. We aimed to assess the role of the Aβ transporter apolipoprotein E (apoE) in the exacerbation of CAA and development of CAA-associated vasculopathy after Aβ immunotherapy. 12 Aβ42-immunized AD (iAD; AN1792, Elan Pharmaceuticals) cases were compared with 28 unimmunized AD (cAD) cases. Immunohistochemistry was quantified for Aβ42, apoE, apoE E4 and smooth muscle actin, and CAA-associated vasculopathy was analyzed. Aβ immunotherapy was associated with redistribution of apoE from cortical plaques to cerebral vessel walls, mirroring the altered distribution of Aβ42. Concentric vessel wall splitting was increased threefold in leptomeningeal vessels after immunotherapy (cAD 6.3 vs iAD 20.6 %, P < 0.001), but smooth muscle cell abnormalities did not differ. The findings suggest that apoE is involved in the removal of plaques and transport of Aβ to the cerebral vasculature induced by Aβ immunotherapy. Immunotherapy was not associated with CAA-related vascular smooth muscle damage, but was accompanied by increased splitting of the vessel wall, perhaps reflecting enhanced deposition and subsequent removal of Aβ. ARIA occurring in some current trials of Aβ immunotherapy may reflect an extreme form of these vascular changes.

  15. Progressive human immunodeficiency virus-associated vasculopathy: time to revise antiretroviral therapy guidelines?

    PubMed

    Ntusi, N B A; Taylor, D; Naidoo, N G; Mendelson, M

    2011-01-01

    Cardiovascular abnormalities were appreciated early in the epidemic of the acquired immunodeficiency syndrome (AIDS), even before the aetiological agent, human immunodeficiency virus (HIV) was isolated and characterised. The aetiology and pathogenesis of cardiovascular disease in HIV infection is still the subject of intense speculation, and is likely multi-factorial. HIV affects every aspect of the cardiac axis, causing pericarditis, myocarditis, cardiomyopathy, coronary artery disease and microvascular dysfunction, valvular heart disease, pulmonary vascular disease and pulmonary hypertension, stroke and peripheral vascular disease. HIV-associated vasculopathy is an increasingly recognised clinical entity, causing high morbidity and increasing mortality in southern Africa, particularly from stroke and cardiovascular disease. HIV causes disease of the vascular tree, either by a direct effect on vascular or perivascular tissue, or indirectly via immune complex-mediated mechanisms, associated opportunistic infections and malignancies. As a result, highly active antiretroviral therapy (HAART) may have an important role in controlling disease progression. We report a case of histologically defined primary HIV vasculopathy in which the chance to start HAART was initially missed and in which the patient progressed to require bilateral amputations, but obtained disease quiescence upon commencement of HAART.

  16. Choroidal Vasculopathy and Retinal Detachment in a Bald Eagle ( Haliaeetus leucocephalus ) With Lead Toxicosis.

    PubMed

    Eid, Ramzi; Guzman, David Sanchez-Migallon; Keller, Krista A; Wiggans, K Tomo; Murphy, Christopher J; LaDouceur, Elise E B; Keel, M Kevin; Reilly, Christopher M

    2016-12-01

    A subadult male bald eagle ( Haliaeetus leucocephalus ) was presented for severe depression and weakness. Physical examination findings included depressed mentation, dehydration, sternal recumbency, poor body condition, and bilateral, whole-head, horizontal nystagmus. A heavy-metal panel was performed, and blood lead levels were 6.1 ppm. Treatment for lead poisoning was initiated, including subcutaneous fluids and parenteral calcium-disodium ethylenediaminetetraacetic acid, ceftiofur, and meloxicam. Ophthalmic examination findings included absent menace response, absent dazzle reflex, slow and incomplete direct pupillary light reflex, mild anterior uveitis, incipient cataracts, multifocal retinal tears, and retinal separation in both eyes. Because of poor prognosis for vision and release to the wild, the eagle was euthanatized. No lesions were observed on gross postmortem examination. Histologically, extensive myocardial necrosis and multisystemic arteriolar vasculopathy were identified. The eyes were examined after tissue processing, and the vasculopathy extended into the choriocapillaris and was associated with a secondary, bilateral, exudative, retinal detachment. This is the first report in avian species characterizing the histopathologic ocular lesions of lead poisoning.

  17. Therapeutic implications of peptide interactions with G-protein-coupled receptors in diabetic vasculopathy.

    PubMed

    Carrillo-Sepulveda, M A; Matsumoto, T; Nunes, K P; Webb, R C

    2014-05-01

    The dramatic worldwide increase in the prevalence of diabetes has generated an attempt by the scientific community to identify strategies for its treatment and prevention. Vascular dysfunction is a hallmark of diabetes and frequently leads to the development of atherosclerosis, coronary disease-derived myocardial infarction, stroke, peripheral arterial disease and diabetic 'triopathy' (retinopathy, nephropathy and neuropathy). These vascular complications, developing in an increasingly younger cohort of patients with diabetes, contribute to morbidity and mortality. Despite the development of new anti-diabetic or anti-hyperglycaemic drugs, vascular complications remain to be a problem. This warrants a need for new therapeutic strategies to tackle diabetic vasculopathy. There is a growing body of evidence showing that peptide-binding G-protein-coupled receptors (peptide-binding GPCRs) play an important role in the pathophysiology of vascular dysfunction during diabetes. Thus, in this review, we discuss some of the peptide-binding GPCRs involved in the regulation of vascular function that have potential to be a therapeutic target in the treatment of diabetic vasculopathy.

  18. Intracranial large vessel vasculopathy and anaplastic meningioma 19 years after cranial irradiation for acute lymphoblastic leukaemia.

    PubMed

    Foreman, N K; Laitt, R D; Chambers, E J; Duncan, A W; Cummins, B H

    1995-04-01

    A child was diagnosed in 1969 as having acute lymphoblastic leukaemia (ALL) and received chemotherapy. On bone marrow relapse in 1973, he was treated with cranial irradiation (20 Gy) in addition to chemotherapy. He continues in complete remission 19 years after his relapse. At age 25 years, he presented with headaches and left hemiparesis. Computerised tomograph demonstrated a large, enhancing right-sided intracranial tumour. Angiography was performed and showed the right internal carotid artery was occluded. Most of the right hemisphere was supplied from the external carotid via the middle meningeal artery. The left posterior cerebral artery and the left anterior cerebral artery were absent presumably as a result of radiation-induced arteritis. A resection of an anaplastic meningioma arising from the right sphenoidal ridge was achieved. There was a rapid improvement in function and he returned to work. Vasculopathy of the large intracranial arteries has been described after high dose radiation. It may occur as in this case after moderate dose radiation. There is a correlation with meningioma. There is a possibility that large artery vasculopathy will be present in a proportion of patients irradiated for ALL. The long lag time between irradiation and the development of meningioma may mean that, as survivors of childhood ALL enter their third decade since cure, this tumour may be seen increasingly.

  19. Mechanisms of allograft rejection of corneal endothelium

    SciTech Connect

    Tagawa, Y.; Silverstein, A.M.; Prendergast, R.A.

    1982-07-01

    The local intraocular graft-vs.-host (GVH) reaction, involving the destruction of the corneal endothelial cells of the rabbit host by sensitized donor lymphoid cells, has been used to study the mechanism of corneal allograft rejection. Pretreatment of donor cells with a specific mouse monoclonal hybridoma anti-T cell antibody and complement suppresses the destructive reaction, suggesting that a cellular-immune mechanism is primarily involved. Pretreatment of donor cells with mitomycin-C completely abolishes the local GVH reaction, indicating that the effector lymphocytes must undergo mitosis within the eye before they can engage in target cell destruction. Finally, studies of the local GVH reaction in irradiated leukopenic recipients or in preinflamed rabbit eyes suggest that host leukocytes may contribute nonspecifically to enhance the destructive process. These studies show that the local ocular GVH reaction may provide a useful model for the study of the mechanisms involved in the rejection of corneal allografts.

  20. Cortical bone allografting in femoral head necrosis.

    PubMed

    Delloye, C; Cornu, O

    1999-01-01

    Ten femoral heads (six patients) with avascular necrosis were operated on using a fibular allograft. The procedure included core decompression followed by insertion of a cortical bone graft in order to relieve mechanical stresses from the overlying subchondral bone. The presence of the supporting graft should avoid an expected collapse or prevent its worsening if already present. A freeze-dried and processed cortical bone allograft was preferred to an autograft. Weightbearing was normally and fully resumed at the second postoperative month. There were three failures within the first year, four satisfactory results, in which the hip was replaced after 4 years while there are still 3 hips that have been preserved from arthroplasty in young patients after 5 years. The technique is easy and able to substantially delay an arthroplasty in an active patient.

  1. Perforations of cortical bone allografts improve their incorporation.

    PubMed

    Delloye, Christian; Simon, Patrick; Nyssen-Behets, Catherine; Banse, Xavier; Bresler, Franck; Schmitt, Daniel

    2002-03-01

    The incorporation of perforated cortical bone allografts was compared with non-perforated allografts. A 5-cm circumferential defect in the middiaphysis at the tibia was created in adult sheep. A frozen tibial allograft was implanted and fixed with a locked nail for 6 months. There was no postoperative immobilization. Group I consisted of eight sheep with non-perforated allografts, whereas Group II was comprised of 10 sheep with perforated allografts. Union was evaluated radiographically, whereas the central part of the allograft had a densitometric evaluation. Creeping substitution was assessed on microradiographs from cross-sections of the central 3 cm of graft by measurement of porosity and percentage of new and old bone area within the confines of the graft. The width of periosteal and endosteal callus also was determined. There was no statistical difference between both groups for the union score and bone density. However, the cortical bone graft porosity and the amount of new bone within the cortical bone differed significantly between the perforated allografts and the non-perforated ones. Periosteal callus was similar in both groups, whereas endosteal callus was significantly more wide and extended in the perforated allografts. Perforation of a cortical bone substantially improved the amount of newly formed bone by the host when compared with a non-perforated bone. The creation of channels seemed to increase the interface between living soft tissues of the host and the allografted bone with a resulting enhanced incorporation.

  2. Osteoarticular and Total Elbow Allograft Reconstruction With Severe Bone Loss

    PubMed Central

    Busfield, Benjamin T.; Khorshad, Daniel S.; Hornicek, Francis J.; Mankin, Henry J.

    2008-01-01

    Osteoarticular allograft reconstruction is an option in patients with massive periarticular elbow bone loss secondary to tumor surgery or trauma. Our consecutive series consisted of 18 patients with tumors and one patient with trauma. Reconstruction consisted of 16 hemiarticular allografts and three total elbow osteoarticular allografts; patients had a minimum followup of 2 years (mean, 9.9 years; range, 2–12 years). For patients who had hemiarticular allografts, 14 of 16 were able to return to their preoperative level of occupational function, with one patient experiencing failure of the allograft from infection. For the three patients who had total elbow allograft reconstructions, all had degenerative changes develop after surgery and two of the allografts failed. Complications occurred in six of 19 patients. Hemiarticular elbow allograft reconstruction is useful for limb salvage with massive bone loss. Total elbow allograft reconstructions have a high failure rate in the mid-term. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18196394

  3. Procurement of hand and arm allografts.

    PubMed

    Cetrulo, Curtis L; Kovach, Stephen J

    2013-12-01

    Upper extremity transplantation has been at the forefront of vascularized composite allotransplantation. There have been more hand and upper extremity transplants than any other kinds of vascularized composite allotransplantation. However, it is a new and evolving field. Reconstructive surgeons are relative newcomers to the field of transplantation, and the procurement of upper extremity allografts has many subtleties that will differ depending on the intended recipient. However, there are certain principles that can be adhered to that this review serves to elucidate.

  4. [Tubulointerstitial rejection of renal allografts].

    PubMed

    Malušková, Jana; Honsová, Eva

    2015-01-01

    Tubulo-intersticial rejection represents T-cell mediated rejection of kidney allografts with the morphology of immune-mediated interstitial nephritis. Diagnosis is dependent on the histopathological evaluation of a graft biopsy sample. The key morphological features are interstitial inflammatory infiltrate and damage to tubular epithelial cell which in severe cases can result in the ruptures of the tubular basement membranes. The differential diagnosis of tubulo-interstitial rejection includes acute interstitial nephritis and viral inflammatory kidney diseases, mainly polyomavirus nephropathy.

  5. Digital Reconstruction with a Nonfrozen Osteotendinous Allograft, Nerve Allografts, and Autogenous Radial Free Flap.

    PubMed

    Iglesias, Martin; Butrón, Patricia; Palafox, Damian; Cruz-Reyes, Angel U

    2015-08-01

    A 21-year-old man underwent amputation of his second to fifth fingers at the proximal phalanx level on the right hand. The third and fourth fingers were reconstructed with 2 toe-to-hand free transfers. The fifth digit was reconstructed with a nonfrozen osteotendinous allograft, nerve allografts, and autogenous radial free flap without immunosuppression. The patient was lost to follow-up for 19 years. He received no rehabilitation. He reported that he had experienced no adverse reactions to the materials or the graft, or infection, or fractures. No additional surgical procedures were performed. Today, the digit is functional and has acceptable aesthetic appearance. This outcome is similar to those obtained in digits reconstructed with frozen osteotendinous allografts and autologous cutaneous covers and opens the possibility for future research.

  6. The Role of Lymphoid Neogenesis in Allografts.

    PubMed

    Hsiao, H-M; Li, W; Gelman, A E; Krupnick, A S; Kreisel, D

    2016-04-01

    De novo induction of organized lymphoid aggregates at nonlymphoid sites has been observed in many chronic inflammatory conditions where foreign antigens such as infectious agents, autoantigens or alloantigens, persist. The prevailing opinion in the field of transplantation is that lymphoid neogenesis within allografts is detrimental to the establishment of immune tolerance. These structures, commonly referred to as tertiary lymphoid organs (TLOs), are thought to contribute to graft rejection by generating and propagating local alloimmune responses. However, recent studies have shown that TLOs rich in regulatory Foxp3(+) cells are present in long-term accepting allografts. The notion that TLOs can contribute to the local downregulation of immune responses has been corroborated in other chronic inflammation models. These findings suggest that contrary to previous suggestions that the induction of TLOs in allografts is necessarily harmful, the induction of "tolerogenic" TLOs may prove advantageous. In this review, we discuss our current understanding of how TLOs are induced and how they regulate immune responses with a particular focus on alloimmunity.

  7. The Role of Lymphoid Neogenesis in Allografts

    PubMed Central

    Hsao, Hsi-Min; Li, Wenjun; Gelman, Andrew E.; Krupnick, Alexander S.; Kreisel, Daniel

    2016-01-01

    De novo induction of organized lymphoid aggregates at non-lymphoid sites has been observed in many chronic inflammatory conditions where foreign antigens such as infectious agents, auto- or alloantigens, persist. The prevailing opinion in the field of transplantation is that lymphoid neogenesis within allografts is detrimental to the establishment of immune tolerance. These structures, commonly referred to as tertiary lymphoid organs (TLOs), are thought to contribute to graft rejection by generating and propagating local alloimmune responses. However, recent studies have shown that TLOs rich in regulatory Foxp3+ cells are present in long term accepting allografts. The notion that TLOs can contribute to the local downregulation of immune responses has been corroborated in other chronic inflammation models. These findings suggest that contrary to previous suggestions that the induction of TLOs in allografts is necessarily harmful, the induction of “tolerogenic” TLOs may prove advantageous. In this review, we discuss our current understanding of how TLOs are induced and how they regulate immune responses with a particular focus on alloimmunity. PMID:26614734

  8. Exploring the dominant role of Cav1 channels in signalling to the nucleus

    PubMed Central

    Ma, Huan; Cohen, Samuel; Li, Boxing; Tsien, Richard W.

    2012-01-01

    Calcium is important in controlling nuclear gene expression through the activation of multiple signal-transduction pathways in neurons. Compared with other voltage-gated calcium channels, CaV1 channels demonstrate a considerable advantage in signalling to the nucleus. In this review, we summarize the recent progress in elucidating the mechanisms involved. CaV1 channels, already advantaged in their responsiveness to depolarization, trigger communication with the nucleus by attracting colocalized clusters of activated CaMKII (Ca2+/calmodulin-dependent protein kinase II). CaV2 channels lack this ability, but must work at a distance of >1 μm from the CaV1-CaMKII co-clusters, which hampers their relative efficiency for a given rise in bulk [Ca2+]i (intracellular [Ca2+]). Moreover, Ca2+ influx from CaV2 channels is preferentially buffered by the ER (endoplasmic reticulum) and mitochondria, further attenuating their effectiveness in signalling to the nucleus. PMID:23088728

  9. Low Voltage Activation of KCa1.1 Current by Cav3-KCa1.1 Complexes

    PubMed Central

    Rehak, Renata; Bartoletti, Theodore M.; Engbers, Jordan D. T.; Berecki, Geza; Turner, Ray W.; Zamponi, Gerald W.

    2013-01-01

    Calcium-activated potassium channels of the KCa1.1 class are known to regulate repolarization of action potential discharge through a molecular association with high voltage-activated calcium channels. The current study examined the potential for low voltage-activated Cav3 (T-type) calcium channels to interact with KCa1.1 when expressed in tsA-201 cells and in rat medial vestibular neurons (MVN) in vitro. Expression of the channel α-subunits alone in tsA-201 cells was sufficient to enable Cav3 activation of KCa1.1 current. Cav3 calcium influx induced a 50 mV negative shift in KCa1.1 voltage for activation, an interaction that was blocked by Cav3 or KCa1.1 channel blockers, or high internal EGTA. Cav3 and KCa1.1 channels coimmunoprecipitated from lysates of either tsA-201 cells or rat brain, with Cav3 channels associating with the transmembrane S0 segment of the KCa1.1 N-terminus. KCa1.1 channel activation was closely aligned with Cav3 calcium conductance in that KCa1.1 current shared the same low voltage dependence of Cav3 activation, and was blocked by voltage-dependent inactivation of Cav3 channels or by coexpressing a non calcium-conducting Cav3 channel pore mutant. The Cav3-KCa1.1 interaction was found to function highly effectively in a subset of MVN neurons by activating near –50 mV to contribute to spike repolarization and gain of firing. Modelling data indicate that multiple neighboring Cav3-KCa1.1 complexes must act cooperatively to raise calcium to sufficiently high levels to permit KCa1.1 activation. Together the results identify a novel Cav3-KCa1.1 signaling complex where Cav3-mediated calcium entry enables KCa1.1 activation over a wide range of membrane potentials according to the unique voltage profile of Cav3 calcium channels, greatly extending the roles for KCa1.1 potassium channels in controlling membrane excitability. PMID:23626738

  10. Distinct roles for Cav2.1–2.3 in activity-dependent synaptic dynamics

    PubMed Central

    Ricoy, Ulises M.

    2014-01-01

    Synaptic transmission throughout most of the CNS is steeply dependent on presynaptic calcium influx through the voltage-gated calcium channels Cav2.1–Cav2.3. In addition to triggering exocytosis, this calcium influx also recruits short-term synaptic plasticity. During the complex patterns of presynaptic activity that occur in vivo, several forms of plasticity combine to generate a synaptic output that is dynamic, in which the size of a given excitatory postsynaptic potential (EPSP) in response to a given spike depends on the short-term history of presynaptic activity. It remains unclear whether the different Cav2 channels play distinct roles in defining these synaptic dynamics and, if so, under what conditions different Cav2 family members most effectively determine synaptic output. We examined these questions by measuring the effects of calcium channel-selective toxins on synaptic transmission at the Schaffer collateral synapse in hippocampal slices from adult mice in response to both low-frequency stimulation and complex stimulus trains derived from in vivo recordings. Blockade of Cav2.1 had a greater inhibitory effect on synaptic transmission during low-frequency components of the stimulus train than on synaptic transmission during high-frequency components of the train, indicating that Cav2.1 had a greater fractional contribution to synaptic transmission at low frequencies than at high frequencies. Relative to Cav2.1, Cav2.2 had a disproportionately reduced contribution to synaptic transmission at frequencies >20 Hz, while Cav2.3 had a disproportionately increased contribution to synaptic transmission at frequencies >1 Hz. These activity-dependent effects of different Cav2 family members shape the filtering characteristics of GABAB receptor-mediated presynaptic inhibition. Thus different Cav2 channels vary in their coupling to synaptic transmission over different frequency ranges, with consequences for the frequency tuning of both synaptic dynamics and

  11. Pharmacognostic standardization of stems of Thespesia lampas (Cav.) Dalz & Gibs

    PubMed Central

    Chumbhale, DS; Upasani, CD

    2012-01-01

    Objective To establish the standardization parameters for complete pharmacognostic evaluation of stems of Thespesia lampas (T. lampas) (Cav.) Dalz & Gibs (Malvaceae), an important plant in the Indian system of medicine. Methods Morphological, microscopical, physico-chemical evaluations, florescence analysis of T. lampas stems were investigated and preliminary phytochemical analysis, GC-MS analysis and HPTLC fingerprinting were carried out for qualitative phytochemical evaluation of various extracts of stems of T. lampas. Results Chemo-microscopy revealed the presence of lignin, starch grains and calcium oxalate crystals. Physico-chemical evaluation used to determine numerical standards showed a result with total ash (9.03 ± 0.05) % w/w, acid insoluble ash (1.50 ± 0.01) % w/w, water soluble ash (2.51 ± 0.02) % w/w, sulphated ash (7.50 ± 0.01) % w/w, ethanol soluble extractive (0.24 ± 0.02) % w/w, water soluble extractive (0.08 ± 0.01) % w/w, moisture content (6.03 ± 0.05) % w/w and total crude fibre content of stem powder (47.36 ± 0.32) % w/w. Behavior characteristics of the stem powder showed presence of steroids, starch, alkaloid, flavonoids and proteins. Preliminary phytochemical analysis revealed presence of glycosides, phenolic compounds, tannins, steroids, saponins, flavonoids, carbohydrates and proteins. GC-MS analysis showed the presence of fatty acids such as dodecanoic acid, tetradecanoic acid, n-hexadecanoic acid, 9-tetradecenal and HPTLC fingerprinting revealed the presence of β-sitosterol and quercetin in stems of T. lampas. Conclusions The pharmacognostic standardization of T. lampas is useful towards establishing standards for quality, purity and sample identification. PMID:23569930

  12. Densin-180 controls the trafficking and signaling of L-type voltage-gated Cav1.2 Ca(2+) channels at excitatory synapses.

    PubMed

    Wang, Shiyi; Stanika, Ruslan I; Wang, Xiaohan; Hagen, Jussara; Kennedy, Mary B; Obermair, Gerald J; Colbran, Roger J; Lee, Amy

    2017-03-31

    Voltage-gated Cav1.2 and Cav1.3 (L-type) Ca(2+) channels regulate neuronal excitability, synaptic plasticity, and learning and memory. Densin-180 (densin) is an excitatory synaptic protein that promotes Ca(2+)-dependent facilitation of voltage-gated Cav1.3 Ca(2+) channels in transfected cells. Mice lacking densin (densin KO) exhibit defects in synaptic plasticity, spatial memory, and increased anxiety-related behaviors --phenotypes that more closely match those in mice lacking Cav1.2 than Cav1.3. Thus, we investigated the functional impact of densin on Cav1.2. We report that densin is an essential regulator of Cav1.2 in neurons, but has distinct modulatory effects compared to its regulation of Cav1.3. Densin binds to the N-terminal domain of Cav1.2 but not Cav1.3, and increases Cav1.2 currents in transfected cells and in neurons. In transfected cells, densin accelerates the forward trafficking of Cav1.2 channels without affecting their endocytosis. Consistent with a role for densin in increasing the number of postsynaptic Cav1.2 channels, overexpression of densin increases the clustering of Cav1.2 in dendrites of hippocampal neurons in culture. Compared to wild-type mice, the cell-surface levels of Cav1.2 in the brain as well as Cav1.2 current density and signaling to the nucleus are reduced in neurons from densin KO mice. We conclude that densin is an essential regulator of neuronal Cav1 channels and ensures efficient Cav1.2 Ca(2+) signaling at excitatory synapses.SIGNIFICANCE STATEMENTThe number and localization of voltage-gated Cav Ca(2+) channels are crucial determinants of neuronal excitability and synaptic transmission. We report that a protein that is highly enriched at excitatory synapses in the brain, densin-180, enhances the cell-surface trafficking and postsynaptic localization of Cav1.2 L-type Ca(2+) channels in neurons. This interaction promotes coupling of Cav1.2 channels to activity-dependent gene transcription. Our results reveal a mechanism that

  13. The CAV program for numerical evaluation of laminar natural convection heat transfer in vertical rectangular cavities

    NASA Astrophysics Data System (ADS)

    Novak, Milos H.; Nowak, Edwin S.

    1993-12-01

    To analyze the laminar natural convection heat transfer and fluid flow distribution in vertical rectangular cavities with or without inner partitions, the personal computer finite difference program entitled CAV is used. The CAV program was tested successfully for slender cavities with aspect ratios as high as R = H/ L = 90 and for the Grashof numbers, based on the cavity height, up to GrH = 3 x10 9. To make the CAV program useful for a number of applications, various types of boundary conditions can also be imposed on the program calculations. Presented are program applications dealing with the 2-D numerical analysis of natural convection heat transfer in very slender window cavities with and without small inner partitions and recommendations are made for window design.

  14. Cav1.3 Channels as Key Regulators of Neuron-Like Firings and Catecholamine Release in Chromaffin Cells

    PubMed Central

    Vandael, David H.F.; Marcantoni, Andrea; Carbone, Emilio

    2015-01-01

    Neuronal and neuroendocrine L-type calcium channels (Cav1.2, Cav1.3) open readily at relatively low membrane potentials and allow Ca2+ to enter the cells near resting potentials. In this way, Cav1.2 and Cav1.3 shape the action potential waveform, contribute to gene expression, synaptic plasticity, neuronal differentiation, hormone secretion and pacemaker activity. In the chromaffin cells (CCs) of the adrenal medulla, Cav1.3 is highly expressed and is shown to support most of the pacemaking current that sustains action potential (AP) firings and part of the catecholamine secretion. Cav1.3 forms Ca2+-nanodomains with the fast inactivating BK channels and drives the resting SK currents. These latter set the inter-spike interval duration between consecutive spikes during spontaneous firing and the rate of spike adaptation during sustained depolarizations. Cav1.3 plays also a primary role in the switch from “tonic” to “burst” firing that occurs in mouse CCs when either the availability of voltage-gated Na channels (Nav) is reduced or the β2 subunit featuring the fast inactivating BK channels is deleted. Here, we discuss the functional role of these “neuron-like” firing modes in CCs and how Cav1.3 contributes to them. The open issue is to understand how these novel firing patterns are adapted to regulate the quantity of circulating catecholamines during resting condition or in response to acute and chronic stress. PMID:25966692

  15. [Effect of overexpression of CAV1 mediated by lentivirus on proliferation and apoptosis of HL-60 cells].

    PubMed

    Ma, Wei; Wang, Di-Di; Wang, Zhao; Zhu, Gui-Ming; Zhang, Peng-Xia

    2013-08-01

    This study was purposed to explore the effect of lentivirus-mediated CAV1 overexpression on proliferation and apoptosis in HL-60 cells. Recombinant lentiviral expression vector pcDNA-EF1-CAV1 was constructed, and cotransfected the 293TN cells with a mixture of pPACK packaging plasmids. Then collecting virus suspension infects the HL-60 cells, which make CAV1 gene stable transfection and high expression in the cells. The CAV1 protein expression status in HL-60 cells transfected was evaluated through Western blot method. Proliferative activity and apoptosis of HL-60 cells before and after transfection were detected by CCK-8 method and flow cytometry, respectively. The results showed that the PCR-positive clone screening and results of nucleotide sequencing confirmed that the CAV1 gene inserted into the expression vector pcDNA-EF1-GFP correctly, recombinant lentiviral particles Lv-CAV1 transfected HL-60 cells successfully and with transfection rate up to 90%. The result of Western blot showed that CAV1 protein expression in HL-60 cells significantly increased at 48 hours after transfection. CCK-8 result indicated that cell proliferation activity increased at 48 h after transfection (P < 0.05), flow cytometry testing results displayed that apoptosis rate of HL-60 cells obviously decreased after transfection (P < 0.01). It is concluded that the overexpression of CAV1 in HL-60 cells can inhibit cell proliferation activity and promote cell apoptosis.

  16. The use of allografts in paediatric orthopaedic surgery.

    PubMed

    Docquier, Pierre-Louis; Paul, Laurent; Mousny, Maryline; Cornu, Olivier; Delloye, Christian

    2007-10-01

    Autograft harvesting in a growing child sometimes leads to disastrous consequences. Allograft can advantageously replace autograft in the majority of the cases. This overview presents the most frequently used allografts in paediatric orthopaedic surgery and discusses their benefits. Illustrative cases are presented to highlight specific indications.

  17. CaV3.1 is a tremor rhythm pacemaker in the inferior olive

    PubMed Central

    Park, Young-Gyun; Park, Hye-Yeon; Lee, C. Justin; Choi, Soonwook; Jo, Seonmi; Choi, Hansol; Kim, Yang-Hann; Shin, Hee-Sup; Llinas, Rodolfo R.; Kim, Daesoo

    2010-01-01

    The rhythmic motor pathway activation by pacemaker neurons or circuits in the brain has been proposed as the mechanism for the timing of motor coordination, and the abnormal potentiation of this mechanism may lead to a pathological tremor. Here, we show that the potentiation of CaV3.1 T-type Ca2+ channels in the inferior olive contributes to the onset of the tremor in a pharmacological model of essential tremor. After administration of harmaline, 4- to 10-Hz synchronous neuronal activities arose from the IO and then propagated to cerebellar motor circuits in wild-type mice, but those rhythmic activities were absent in mice lacking CaV3.1 gene. Intracellular recordings in brain-stem slices revealed that the CaV3.1-deficient inferior olive neurons lacked the subthreshold oscillation of membrane potentials and failed to trigger 4- to 10-Hz rhythmic burst discharges in the presence of harmaline. In addition, the selective knockdown of CaV3.1 gene in the inferior olive by shRNA efficiently suppressed the harmaline-induced tremor in wild-type mice. A mathematical model constructed based on data obtained from patch-clamping experiments indicated that harmaline could efficiently potentiate CaV3.1 channels by changing voltage-dependent responsiveness in the hyperpolarizing direction. Thus, CaV3.1 is a molecular pacemaker substrate for intrinsic neuronal oscillations of inferior olive neurons, and the potentiation of this mechanism can be considered as a pathological cause of essential tremor. PMID:20498062

  18. Surgical techniques and radiological findings of meniscus allograft transplantation.

    PubMed

    Lee, Hoseok; Lee, Sang Yub; Na, Young Gon; Kim, Sung Kwan; Yi, Jae Hyuck; Lim, Jae Kwang; Lee, So Mi

    2016-08-01

    Meniscus allograft transplantation has been performed over the past 25 years to relieve knee pain and improve knee function in patients with an irreparable meniscus injury. The efficacy and safety of meniscus allograft transplantation have been established in numerous experimental and clinical researches. However, there is a lack of reviews to aid radiologists who are routinely interpreting images and evaluating the outcome of the procedures, and also meniscus allograft transplantation is not widely performed in most hospitals. This review focuses on the indications of the procedure, the different surgical techniques used for meniscus allograft transplantation according to the involvement of the lateral and medial meniscus, and the associated procedures. The postoperative radiological findings and surgical complications of the meniscus allograft transplantation are also described in detail.

  19. Cacna1c (Cav1.2) Modulates Electroencephalographic Rhythm and Rapid Eye Movement Sleep Recovery

    PubMed Central

    Kumar, Deependra; Dedic, Nina; Flachskamm, Cornelia; Voulé, Stephanie; Deussing, Jan M.; Kimura, Mayumi

    2015-01-01

    Study Objectives: The CACNA1C gene encodes the alpha 1C (α1C) subunit of the Cav1.2 voltage-dependent L-type calcium channel (LTCC). Some of the other voltage-dependent calcium channels, e.g., P-/Q-type, Cav2.1; N-type, Cav2.2; E-/R-type, Cav2.3; and T-type, Cav3.3 have been implicated in sleep modulation. However, the contribution of LTCCs to sleep remains largely unknown. Based on recent genome-wide association studies, CACNA1C emerged as one of potential candidate genes associated with both sleep and psychiatric disorders. Indeed, most patients with mental illnesses have sleep problems and vice versa. Design: To investigate an impact of Cav1.2 on sleep-wake behavior and electroencephalogram (EEG) activity, polysomnography was performed in heterozygous Cacna1c (HET) knockout mice and their wild-type (WT) littermates under baseline and challenging conditions (acute sleep deprivation and restraint stress). Measurements and Results: HET mice displayed significantly lower EEG spectral power than WT mice across high frequency ranges (beta to gamma) during wake and rapid eye movement (REM) sleep. Although HET mice spent slightly more time asleep in the dark period, daily amounts of sleep did not differ between the two genotypes. However, recovery sleep after exposure to both types of challenging stress conditions differed markedly; HET mice exhibited reduced REM sleep recovery responses compared to WT mice. Conclusions: These results suggest the involvement of Cacna1c (Cav1.2) in fast electroencephalogram oscillations and REM sleep regulatory processes. Lower spectral gamma activity, slightly increased sleep demands, and altered REM sleep responses found in heterozygous Cacna1c knockout mice may rather resemble a sleep phenotype observed in schizophrenia patients. Citation: Kumar D, Dedic N, FLachskamm C, Voulé S, Deussing JM, Kimura M. Cacna1c (Cav1.2) modulates electroencephalographic rhythm and rapid eye movement sleep recovery. SLEEP 2015;38(9):1371–1380. PMID

  20. Extensive Acquired Telangiectasias: Comparison of Generalized Essential Telangiectasia and Cutaneous Collagenous Vasculopathy.

    PubMed

    Knöpfel, N; Martín-Santiago, A; Saus, C; Escudero-Góngora, M M; Del Pozo, L J; Gómez, C

    2017-04-01

    The late development of symmetrical, ascending telangiectasias over an extensive area of the skin with no associated systemic manifestations is a common presentation of generalized essential telangiectasia (GET). It was recently suggested that cutaneous collagenous vasculopathy (CCV) is clinically identical to GET but that the 2 conditions can be distinguished by their distinctive histopathologic findings. We present 2 patients, both women, with multiple telangiectasias and describe the histopathologic findings that led to the diagnoses of GET and CCV. Dermoscopic findings in both cases were similar, except that the older telangiectasias in the patient with CCV were violaceous and distributed in a tortuous, serpentine pattern. During follow-up 12 years for the woman with GET and 42 years for the woman with CCV we saw that in GET the lesions remained stable in appearance whereas in CCV there was progressive darkening and morphological changes eventually resulting in superficial varicose veins.

  1. Nonthrombotic proliferative vasculopathy associated with antiphospholipid antibodies: A case report and literature review.

    PubMed

    Lee, Jeong Seok; Kim, Hyojin; Lee, Eun Bong; Song, Yeong Wook; Park, Jin Kyun

    2016-08-18

    A 20-year-old man presented with recurrent hemoptysis for seven months. A small subpleural nodule in his right lower lobe was found and excised surgically. Based on the presence of antiphospholipid antibodies (aPL) and vascular wall hypertrophy without vasculitis or an intraluminal thrombus, nonthrombotic proliferative vasculopathy (NTPV) affecting pulmonary arteries was diagnosed. Recently, aPL have been postulated to directly induce the proliferation of vascular cells in the intima and media, leading to NTPV. We review 5 cases of NTPV-associated aPL with critical ischemia in the lower extremities and gastrointestinal infarction. NTPV-associated aPL might be distinct from classic antiphospholipid syndrome and should be considered in aPL-positive patients who present with vascular occlusions of medium-sized vessels in the absence of atherosclerotic risk factors and systemic or local inflammation.

  2. Lupus vasculopathy combined with renal infarction: unusual manifestation of lupus nephritis.

    PubMed

    Sugimoto, Toshiro; Kanasaki, Keizo; Morita, Yoshikata; Yokomaku, Yukiyo; Narita, Mitsuhiro; Koyama, Tetsuro; Tanaka, Yuki; Kashiwagi, Atsunori; Koya, Daisuke

    2005-11-01

    A 30-year-old woman with a 10-year history of systemic lupus erythematosus was admitted to our hospital because of the onset of hypertension and renal dysfunction. Renal arteriogram revealed multiple renal infarctions, and cut-off or tapering-stenosis in the interlobular arteries. Renal biopsy showed concentric intimal thickening with narrowed lumen in some arterioles and deposition of IgG/IgM/complement 3 in the wall of arteriole without any active lesions or immune complex deposition in glomeruli. The present case indicates that this type of renal vascular lesion in lupus nephritis, lupus vasculopathy, may cause renal infarction and the loss of renal function without active glomerular lesions.

  3. Testicular hemorrhage, necrosis, and vasculopathy: likely manifestations of intermittent torsion that clinically mimic a neoplasm.

    PubMed

    Kao, Chia-Sui; Zhang, Chen; Ulbright, Thomas M

    2014-01-01

    We report 30 cases of testicular hemorrhage and/or necrosis with associated vascular damage that caused clinical concern for a neoplasm and that raised the question of a vasculitis syndrome on pathologic examination. The patients were 12 to 66 years old (median, 33 y) and presented with pain (n=15), mass (n=12), or both (n=2); 1 case had no available clinical information. Ultrasonographic interpretations included a neoplasm in the differential diagnoses in 14 of 18 cases in which this information was available, and most (n=24) had orchiectomy because of this possibility. Only 4 were clinically suspected to represent testicular infarction. Circumscribed, hemorrhagic lesions occurred in 10 cases, less demarcated hemorrhagic foci in 5, and discrete nodules or ill-defined foci of varying color and consistency in the remainder. No clear testicular lesion was described in 2, with 1 of these having a "dusky" appearance. On microscopic examination all but 1 case showed damaged blood vessels (vasculopathy), with either associated hemorrhage/hematoma (n=24) and/or areas of parenchymal necrosis (n=21). One case showed only segmental tubular atrophy with interstitial inflammation and vasculopathy; no infarct or hemorrhage was identified. A variety of vascular changes was identified, including prominent intimal thickening in arteries (n=22) and fibrinoid change in both arteries (n=5) and vessels of indeterminate type (n=8). Medial fibrosis was present in veins (n=12) and vessels of indeterminate type (n=4), whereas thrombi (remote, recanalized, and/or recent) occurred in arteries (n =7), veins (n=9), and vessels of indeterminate type (n=11). Dilated, blood-filled vessels were present in the testis and/or paratestis in 15 cases. In addition, 7 cases showed arteriolar hyalinization, and 19 had inflammation of blood vessels. The latter was lymphohistiocytic and mostly light but occasionally prominent (n=5). Interstitial inflammation was seen adjacent to damaged testicular

  4. Isolated Placental Inflammation and Vasculopathy: Clinical Implications in the Extremely Low Birth Weight Infants.

    PubMed

    Verma, Rita P; Zhao, Yuan; Niwas, Ram; Kaplan, Cynthia

    2016-01-01

    The predictive values of placental histopathologies are compromised by a non-segregation of common anomalies. The effects of isolated pure placental inflammation (PI) and vasculopathy-coagulopathy (PV) were compared with normal (NL) placentas in extremely premature infants (ELBW, birth weight < 1000 g). PI infants required lower peak inspiratory pressure on day 3. More infants in PV were oxygen dependence on day 28. PV had an increased risk of intraventricular-periventricular hemorrhage (IVH, OR 4.9, 95% CI 1-24.7, p = 0.05). NL infants were unexposed to PPROM or maternal hypertension, had highest requirement for surfactant, did not develop IVH and periventricular leukomalacia (PVL) and none of them were Caucasian.

  5. Coagulation Activation in Children with Sickle Cell Disease Is Associated with Cerebral Small Vessel Vasculopathy

    PubMed Central

    Colombatti, Raffaella; De Bon, Emiliano; Bertomoro, Antonella; Casonato, Alessandra; Pontara, Elena; Omenetto, Elisabetta; Saggiorato, Graziella; Steffan, Agostino; Damian, Tamara; Cella, Giuseppe; Teso, Simone; Manara, Renzo; Rampazzo, Patrizia; Meneghetti, Giorgio; Basso, Giuseppe; Sartori, Maria Teresa; Sainati, Laura

    2013-01-01

    Background Thrombotic complications in Sickle Cell Disease (SCD) arise since infancy, but the role of the coagulation system in children has been poorly explored. To determine its role in the development of clinical complications in childhood we measured coagulation and endothelial parameters in children with SCD at steady state. Methods Markers of thrombin generation, fibrin dissolution and endothelial activation were evaluated in 38 children with SS-Sβ°, 6 with SC disease and 50 age and blood group matched controls. Coagulation variables were correlated with markers of hemolysis and inflammation, with the presence of cerebral and lung vasculopathy and with the frequency of clinical complications. Results SS-Sβ° patients presented higher levels of factor VIII, von Willebrand factor antigen (VWF:Ag) and collagen binding activity, tissue plasminogen activator antigen (t-PA:Ag), D-dimer, p-selectin, prothrombin fragment1+2 (F1+2) and lower ADAMTS-13:activity/VWF:Ag (p<0.05) compared to controls and SC patients. In SS-Sβ° patients coagulation variables correlated positively with markers of inflammation, hemolysis, and negatively with HbF (p<0.05). Patients with cerebral silent infarcts showed significant decrease in t-PA:Ag and ADAMTS-13 Antigen and a tendency toward higher D-dimer, F1+2, TAT compared to patients without them. D-dimer was associated with a six fold increased risk of cerebral silent infarcts. No correlation was found between coagulation activation and large vessel vasculopathy or other clinical events except for decreased t-PA:Ag in patients with tricuspid Rigurgitant Velocity >2.5m/sec. Conclusions SS-Sβ° disease is associated with extensive activation of the coagulation system at steady state since young age. ADAMTS-13 and t-PA:Ag are involved in the development of cerebral silent infarcts. PMID:24205317

  6. Splice variants of the CaV1.3 L-type calcium channel regulate dendritic spine morphology

    PubMed Central

    Stanika, Ruslan; Campiglio, Marta; Pinggera, Alexandra; Lee, Amy; Striessnig, Jörg; Flucher, Bernhard E.; Obermair, Gerald J.

    2016-01-01

    Dendritic spines are the postsynaptic compartments of glutamatergic synapses in the brain. Their number and shape are subject to change in synaptic plasticity and neurological disorders including autism spectrum disorders and Parkinson’s disease. The L-type calcium channel CaV1.3 constitutes an important calcium entry pathway implicated in the regulation of spine morphology. Here we investigated the importance of full-length CaV1.3L and two C-terminally truncated splice variants (CaV1.342A and CaV1.343S) and their modulation by densin-180 and shank1b for the morphology of dendritic spines of cultured hippocampal neurons. Live-cell immunofluorescence and super-resolution microscopy of epitope-tagged CaV1.3L revealed its localization at the base-, neck-, and head-region of dendritic spines. Expression of the short splice variants or deletion of the C-terminal PDZ-binding motif in CaV1.3L induced aberrant dendritic spine elongation. Similar morphological alterations were induced by co-expression of densin-180 or shank1b with CaV1.3L and correlated with increased CaV1.3 currents and dendritic calcium signals in transfected neurons. Together, our findings suggest a key role of CaV1.3 in regulating dendritic spine structure. Under physiological conditions it may contribute to the structural plasticity of glutamatergic synapses. Conversely, altered regulation of CaV1.3 channels may provide an important mechanism in the development of postsynaptic aberrations associated with neurodegenerative disorders. PMID:27708393

  7. Divergent control of Cav-1 expression in non-cancerous Li-Fraumeni syndrome and human cancer cell lines

    PubMed Central

    Sherif, Zaki A.; Sultan, Ahmed S.

    2013-01-01

    Li-Fraumeni syndrome (LFS) is primarily characterized by development of tumors exhibiting germ-line mutations in the p53 gene. Cell lines developed from patients of a LFS family have decreased p53 activity as evidenced by the absence of apoptosis upon etoposide treatment. To test our hypothesis that changes in gene expression beyond p53 per se are contributing to the development of tumors, we compared gene expression in non-cancerous skin fibroblasts of LFS-affected (p53 heterozygous) vs. non-affected (p53 wild-type homozygous) family members. Expression analysis showed that several genes were differentially regulated in the p53 homozygous and heterozygous cell lines. We were particularly intrigued by the decreased expression (~88%) of a putative tumor-suppressor protein, caveolin-1 (Cav-1), in the p53-mutant cells. Decreased expression of Cav-1 was also seen in both p53-knockout and p21-knockout HTC116 cells suggesting that p53 controls Cav-1 expression through p21 and leading to the speculation that p53, Cav-1 and p21 may be part of a positive auto-regulatory feedback loop. The direct relationship between p53 and Cav-1 was also tested with HeLa cells (containing inactive p53), which expressed a significantly lower Cav-1 protein. A panel of nonfunctional and p53-deficient colon and epithelial breast cancer cell lines showed undetectable expression of Cav-1 supporting the role of p53 in the control of Cav-1. However, in two aggressively metastasizing breast cancer cell lines, Cav-1 was strongly expressed suggesting a possible role in tumor metastasis. Thus, there is a divergent control of Cav-1 expression as evidenced in non-cancerous Li-Fraumeni syndrome and some aggressive human cancer cell lines. PMID:23114650

  8. Calcium CaV1 channel subtype mRNA expression in Parkinson's disease examined by in situ hybridization.

    PubMed

    Hurley, Michael J; Gentleman, Steve M; Dexter, David T

    2015-03-01

    The factors which make some neurons vulnerable to neurodegeneration in Parkinson's disease while others remain resistant are not fully understood. Studies in animal models of Parkinson's disease suggest that preferential use of CaV1.3 subtypes by neurons may contribute to the neurodegenerative process by increasing mitochondrial oxidant stress. This study quantified the level of mRNA for the CaV1 subtypes found in the brain by in situ hybridization using CaV1 subtype-specific [(35)S]-radiolabelled oligonucleotide probes. In normal brain, the greatest amount of messenger RNA (mRNA) for each CaV1 subtype was found in the midbrain (substantia nigra), with a moderate level in the pons (locus coeruleus) and lower quantities in cerebral cortex (cingulate and primary motor). In Parkinson's disease, the level of CaV1 subtype mRNA was maintained in the midbrain and pons, despite cell loss in these areas. In cingulate cortex, CaV1.2 and CaV1.3 mRNA increased in cases with late-stage Parkinson's disease. In primary motor cortex, the level of CaV1.2 mRNA increased in late-stage Parkinson's disease. The level of CaV1.3 mRNA increased in primary motor cortex of cases with early-stage Parkinson's disease and normalized to near the control level in cases from late-stage Parkinson's disease. The finding of elevated CaV1 subtype expression in cortical brain regions supports the view that disturbed calcium homeostasis is a feature of Parkinson's disease throughout brain and not only a compensatory consequence to the neurodegenerative process in areas of cell loss.

  9. Replication of chicken anemia virus (CAV) requires apoptin and is complemented by VP3 of human torque teno virus (TTV).

    PubMed

    Prasetyo, Afiono Agung; Kamahora, Toshio; Kuroishi, Ayumu; Murakami, Kyoko; Hino, Shigeo

    2009-03-01

    To test requirement for apoptin in the replication of chicken anemia virus (CAV), an apoptin-knockout clone, pCAV/Ap(-), was constructed. DNA replication was completely abolished in cells transfected with replicative form of CAV/Ap(-). A reverse mutant competent in apoptin production regained the full level of DNA replication. DNA replication and virus-like particle (VLP) production of CAV/Ap(-) was fully complemented by supplementation of the wild-type apoptin. The virus yield of a point mutant, CAV/ApT(108)I, was 1/40 that of the wild type, even though its DNA replication level was full. The infectious titer of CAV was fully complemented by supplementing apoptin. Progeny virus was free from reverse mutation for T(108)I. To localize the domain within apoptin molecule inevitable for CAV replication, apoptin-mutant expressing plasmids, pAp1, pAp2, pAp3, and pAp4, were constructed by deleting amino acids 10-36, 31-59, 59-88 and 80-112, respectively. While Ap1 and Ap2 were preferentially localized in nuclei, Ap3 and Ap4 were mainly present in cytoplasm. Although complementation capacity of Ap3 and Ap4 was 1/10 of the wild type, neither of them completely lost its activity. VP3 of TTV did fully complement the DNA replication and VLP of CAV/Ap(-). These data suggest that apoptin is inevitable not only for DNA replication but also VLP of CAV. The common feature of apoptin and TTV-VP3 presented another evidence for close relatedness of CAV and TTV.

  10. LYMPHATIC INJURY AND REGENERATION IN CARDIAC ALLOGRAFTS

    PubMed Central

    Soong, Thing Rinda; Pathak, Arvind; Asano, Hiroshi; Fox-Talbot, Karen; Baldwin, William M

    2009-01-01

    Background: Severed donor heart lymphatics are not anastomosed to recipient lymphatics in cardiac transplantation. We evaluated the effects of cellular infiltrates of T cells and macrophages on the morphology of lymphatics in heart grafts. Methods: Dark Agouti (DA) hearts were transplanted to Lewis or control DA rats on sub-therapeutic doses of cyclosporin. Transplants were examined by immunohistology and quantitative immunofluorescence microscopy using LYVE-1 as a lymphatic marker and CD8 and CD68 as markers for cellular infiltration at selected intervals from 1 to 8 weeks post-transplantation. Results: Allograft inner myocardial lymphatic density decreased by more than 30-fold at 1 week, and recovered to only 15% of the native level at 8 weeks post-transplantation. In contrast, allograft lymphatics in and near the epicardium showed no significant density decline, but increased in size by more than 5-fold at 2 weeks, and sustained about a 3-fold increase at 8 weeks post-transplantation. Lymphatic changes correlated temporally with the extent of T cell and macrophage infiltration in allografts, which peaked at 2-3 weeks post-transplantation. When grafts were retransplanted from allogeneic to isogeneic recipients at 3 weeks post-transplantation, inner lymphatic density returned close to native level within 2 weeks after retransplantation. Conclusions: This is the first characterization of regional and morphological effects of immunological responses on heart lymphatics after transplantation. Elimination of alloimmune responses produces rapid restoration of inner lymphatic vessels, suggesting that lymphatics injured during rejection can recover when rejection is reversed during the post-transplantation course. PMID:20118845

  11. Hip Capsular Reconstruction Using Dermal Allograft.

    PubMed

    Chahla, Jorge; Dean, Chase S; Soares, Eduardo; Mook, William R; Philippon, Marc J

    2016-04-01

    Because hip arthroscopic procedures are increasing in number, complications related to the operation itself are starting to emerge. Whereas the capsule has been recognized as an important static stabilizer for the hip, it has not been until recently that surgeons have realized the importance of its preservation and restoration. Disruption of the capsule during arthroscopic procedures is a potential contributor to postoperative iatrogenic hip instability. In cases of a symptomatic deficient capsule, a capsular reconstruction is mandatory because instability may lead to detrimental chondral and labral changes. The purpose of this report was to describe our technique for arthroscopic hip capsular reconstruction using dermal allograft.

  12. Optimization and Implementation of Long Nerve Allografts

    DTIC Science & Technology

    2014-02-01

    decellularized allografts tested did not perform well in this repair model. Additional evaluations and...2c  was  completed.    All   animals  were  assessed  weekly  until  termination  26  weeks  after   receiving  the...the  engrafted  nerves  were  examined  for  nerve-­‐graft  continuity.     Animals  with  a  loss  of   continuity

  13. Stapled Voltage-Gated Calcium Channel (CaV) α-Interaction Domain (AID) Peptides Act As Selective Protein-Protein Interaction Inhibitors of CaV Function.

    PubMed

    Findeisen, Felix; Campiglio, Marta; Jo, Hyunil; Abderemane-Ali, Fayal; Rumpf, Christine H; Pope, Lianne; Rossen, Nathan D; Flucher, Bernhard E; DeGrado, William F; Minor, Daniel L

    2017-03-17

    For many voltage-gated ion channels (VGICs), creation of a properly functioning ion channel requires the formation of specific protein-protein interactions between the transmembrane pore-forming subunits and cystoplasmic accessory subunits. Despite the importance of such protein-protein interactions in VGIC function and assembly, their potential as sites for VGIC modulator development has been largely overlooked. Here, we develop meta-xylyl (m-xylyl) stapled peptides that target a prototypic VGIC high affinity protein-protein interaction, the interaction between the voltage-gated calcium channel (CaV) pore-forming subunit α-interaction domain (AID) and cytoplasmic β-subunit (CaVβ). We show using circular dichroism spectroscopy, X-ray crystallography, and isothermal titration calorimetry that the m-xylyl staples enhance AID helix formation are structurally compatible with native-like AID:CaVβ interactions and reduce the entropic penalty associated with AID binding to CaVβ. Importantly, electrophysiological studies reveal that stapled AID peptides act as effective inhibitors of the CaVα1:CaVβ interaction that modulate CaV function in an CaVβ isoform-selective manner. Together, our studies provide a proof-of-concept demonstration of the use of protein-protein interaction inhibitors to control VGIC function and point to strategies for improved AID-based CaV modulator design.

  14. ACL reconstruction with BPTB autograft and irradiated fresh frozen allograft*

    PubMed Central

    Sun, Kang; Tian, Shao-qi; Zhang, Ji-hua; Xia, Chang-suo; Zhang, Cai-long; Yu, Teng-bo

    2009-01-01

    Objective: To analyze the clinical outcomes of arthroscopic anterior cruciate ligament (ACL) reconstruction with irradiated bone-patellar tendon-bone (BPTB) allograft compared with non-irradiated allograft and autograft. Methods: All BPTB allografts were obtained from a single tissue bank and the irradiated allografts were sterilized with 2.5 mrad of irradiation prior to distribution. A total of 68 patients undergoing arthroscopic ACL reconstruction were prospectively randomized consecutively into one of the two groups (autograft and irradiated allograft groups). The same surgical technique was used in all operations done by the same senior surgeon. Before surgery and at the average of 31 months of follow-up (ranging from 24 to 47 months), patients were evaluated by the same observer according to objective and subjective clinical evaluations. Results: Of these patients, 65 (autograft 33, irradiated allograft 32) were available for full evaluation. When the irradiated allograft group was compared to the autograft group at the 31-month follow-up by the Lachman test, the anterior drawer test (ADT), the pivot shift test, and KT-2000 arthrometer test, statistically significant differences were found. Most importantly, 87.8% of patients in the autograft group and just only 31.3% in the irradiated allograft group had a side-to-side difference of less than 3 mm according to KT-2000. The failure rate of the ACL reconstruction with irradiated allograft (34.4%) was higher than that with autograft (6.1%). The anterior and rotational stabilities decreased significantly in the irradiated allograft group. According to the overall International Knee Documentation Committee (IKDC), functional and subjective evaluations, and activity level testing, no statistically significant differences were found between the two groups. Besides, patients in the irradiated allograft group had a shorter operation time and a longer duration of postoperative fever. When the patients had a fever, the

  15. Alternative Splicing in CaV2.2 Regulates Neuronal Trafficking via Adaptor Protein Complex-1 Adaptor Protein Motifs

    PubMed Central

    Macabuag, Natsuko

    2015-01-01

    N-type voltage-gated calcium (CaV2.2) channels are expressed in neurons and targeted to the plasma membrane of presynaptic terminals, facilitating neurotransmitter release. Here, we find that the adaptor protein complex-1 (AP-1) mediates trafficking of CaV2.2 from the trans-Golgi network to the cell surface. Examination of splice variants of CaV2.2, containing either exon 37a (selectively expressed in nociceptors) or 37b in the proximal C terminus, reveal that canonical AP-1 binding motifs, YxxΦ and [DE]xxxL[LI], present only in exon 37a, enhance intracellular trafficking of exon 37a-containing CaV2.2 to the axons and plasma membrane of rat DRG neurons. Finally, we identify differential effects of dopamine-2 receptor (D2R) and its agonist-induced activation on trafficking of CaV2.2 isoforms. D2R slowed the endocytosis of CaV2.2 containing exon 37b, but not exon 37a, and activation by the agonist quinpirole reversed the effect of the D2R. Our work thus reveals key mechanisms involved in the trafficking of N-type calcium channels. SIGNIFICANCE STATEMENT CaV2.2 channels are important for neurotransmitter release, but how they are trafficked is still poorly understood. Here, we describe a novel mechanism for trafficking of CaV2.2 from the trans-Golgi network to the cell surface which is mediated by the adaptor protein AP-1. Alternative splicing of exon 37 produces CaV2.2-exon 37a, selectively expressed in nociceptors, or CaV2.2-exon 37b, which is the major splice isoform. Our study reveals that canonical AP-1 binding motifs (YxxΦ and [DE]xxxL[LI]), present in exon 37a, but not 37b, enhance intracellular trafficking of exon 37a-containing CaV2.2 to axons and plasma membrane of DRG neurons. Interaction of APs with CaV2.2 channels may also be key underlying mechanisms for differential effects of the dopamine D2 receptor on trafficking of CaV2.2 splice variants. PMID:26511252

  16. Magnetic resonance angiography-defined intracranial vasculopathy is associated with silent cerebral infarcts and glucose-6-phosphate dehydrogenase mutation in children with sickle cell anaemia.

    PubMed

    Thangarajh, Mathula; Yang, Genyan; Fuchs, Dana; Ponisio, Maria R; McKinstry, Robert C; Jaju, Alok; Noetzel, Michael J; Casella, James F; Barron-Casella, Emily; Hooper, W Craig; Boulet, Sheree L; Bean, Christopher J; Pyle, Meredith E; Payne, Amanda B; Driggers, Jennifer; Trau, Heidi A; Vendt, Bruce A; Rodeghier, Mark; DeBaun, Michael R

    2012-11-01

    Silent cerebral infarct (SCI) is the most commonly recognized cause of neurological injury in sickle cell anaemia (SCA). We tested the hypothesis that magnetic resonance angiography (MRA)-defined vasculopathy is associated with SCI. Furthermore, we examined genetic variations in glucose-6-phosphate dehydrogenase (G6PD) and HBA (α-globin) genes to determine their association with intracranial vasculopathy in children with SCA. Magnetic resonance imaging (MRI) of the brain and MRA of the cerebral vasculature were available in 516 paediatric patients with SCA, enrolled in the Silent Infarct Transfusion (SIT) Trial. All patients were screened for G6PD mutations and HBA deletions. SCI were present in 41·5% (214 of 516) of SIT Trial children. The frequency of intracranial vasculopathy with and without SCI was 15·9% and 6·3%, respectively (P < 0·001). Using a multivariable logistic regression model, only the presence of a SCI was associated with increased odds of vasculopathy (P = 0·0007, odds ratio (OR) 2·84; 95% Confidence Interval (CI) = 1·55-5·21). Among male children with SCA, G6PD status was associated with vasculopathy (P = 0·04, OR 2·78; 95% CI = 1·04-7·42), while no significant association was noted for HBA deletions. Intracranial vasculopathy was observed in a minority of children with SCA, and when present, was associated with G6PD status in males and SCI.

  17. Urinary proteomic analysis of chronic allograft nephropathy

    PubMed Central

    O’Riordan, Edmond; Orlova, Tatyana N.; Mendelev, Natalia; Patschan, Daniel; Kemp, Rowena; Chander, Praveen N.; Hu, Rena; Hao, Gang; Gross, Steven S.; Iozzo, Renato V.; Delaney, Veronica; Goligorsky, Michael S.

    2015-01-01

    The pathogenesis of progressive renal allograft injury, which is termed chronic allograft nephropathy (CAN), remains obscure and is currently defined by histology. Prospective protocolbiopsy trials have demonstrated that clinical and standard laboratory tests are insufficiently sensitive indicators of the development and progression of CAN. The study aim was to determine if CAN could be characterized by urinary proteomic data and identify the proteins associated with disease. The urinary proteome of 75 renal transplant recipients and 20 healthy volunteers was analyzed using surface enhanced laser desorption and ionization MS. Patients could be classified into subgroups with normal histology and Banff CAN grades 2-3 with a sensitivity of 86% and a specificity of 92% by applying the classification algorithm Adaboost to urinary proteomic data. Several urinary proteins associated with advanced CAN were identified including α1-micro-globulin, β2-micro-globulin, prealbumin, and endorepellin, the antiangiogenic C-terminal fragment of perlecan. Increased urinary endorepellin was confirmed by ELISA and increased tissue expression of the endorepellin/perlecan ratio by immunofluoresence analysis of renal biopsies. In conclusion, analysis of urinary proteomic data has further characterized the more severe CAN grades and identified urinary endorepellin, as a potential biomarker of advanced CAN. PMID:21136903

  18. Minimizing the risk of chronic allograft nephropathy.

    PubMed

    Weir, Matthew R; Wali, Ravinder K

    2009-04-27

    Chronic allograft nephropathy, now defined as interstital fibrosis and tubular atrophy not otherwise specified, is a near universal finding in transplant kidney biopsies by the end of the first decade posttransplantation. After excluding death with functioning graft, caused by cardiovascular disease or malignancy, chronic allograft nephropathy is the leading cause of graft failure. Original assumptions were that this was not a modifiable process but inexorable, likely due to past kidney injuries. However, newer understandings suggest that acute or subacute processes are involved, and with proper diagnosis, appropriate interventions can be instituted. Our method involved a review of the primary and secondary prevention trials in calcineurin inhibitor withdrawal. Some of the more important causes of progressive graft deterioration include subclinical cellular or humoral rejection, and chronic calcineurin inhibitor toxicity. Early graft biopsy, assessment of histology, and changes in immunosuppression may be some of the most important measures available to protect graft function. The avoidance of clinical inertia in pursuing subtle changes in graft function is critical. Modification in maintenance immunosuppression may benefit many patients with early evidence of graft deterioration.

  19. CAV1 siRNA Reduces Membrane Estrogen Receptor-α Levels and Attenuates Sexual Receptivity

    PubMed Central

    Christensen, Amy

    2012-01-01

    Although classic estrogen receptors (ER) have been proposed to mediate estradiol signaling, it has been relatively recently that mechanisms of trafficking these receptors have been elucidated. ERα is palmitoylated and associates with caveolin proteins to be targeted to the cell membrane. Caveolins are scaffold proteins that not only traffic ERα to the membrane but also are involved in establishing metabotropic glutamate receptor interactions that are necessary for activating G protein signaling. To demonstrate the role of caveolin proteins in regulating an estradiol-dependent behavior, sexual receptivity, we used small interfering RNA to knock down caveolin-1 (CAV1) expression in the arcuate nucleus of the hypothalamus. In CAV1 knockdown rats, membrane, but not intracellular levels of ERα, were significantly reduced. As expected, estrogenic stimulation of the arcuate nucleus of the hypothalamus to medial preoptic nucleus projection was abrogated in CAV1 knockdown rats, indicating that the membrane-initiated activation of this circuit was compromised. Moreover, estradiol-induced lordosis behavior that is dependent on activation of μ-opioid receptors in the medial preoptic nucleus was also significantly reduced. Thus, CAV1-mediated ERα trafficking to the cell membrane is required for estradiol activation of circuits underlying female sexual receptivity. PMID:22669893

  20. CAV-OX CAVITATION OXIDIATION PROCESS - MAGNUM WATER TECHNOLOGY, INC. - APPLICATIONS ANALYSIS REPORT

    EPA Science Inventory

    This report evaluates the ability of the CAV-OX cavitation oxidation process to remove volatile organic compounds (VOC) present in aqueous wastes. This report also presents economic data based on the Superfund Innovative Technology Evaluation (SITE) Program demonstration and nine...

  1. Variation in seed traits and germination potential of Solanum elaeagnifolium Cav. Following its invasion in Greece

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solanum elaeagnifolium Cav. (Silverleaf nightshade) is presently considered to be one of the worst agricultural weeds around the world including the Mediterranean basin. Plant’s native range is considered to be an area expanding from Southern US to Northern Mexico. Introduced unintentionally from so...

  2. Targeting Sirtuin-1 prolongs murine renal allograft survival and function.

    PubMed

    Levine, Matthew H; Wang, Zhonglin; Xiao, Haiyan; Jiao, Jing; Wang, Liqing; Bhatti, Tricia R; Hancock, Wayne W; Beier, Ulf H

    2016-05-01

    Current immunosuppressive medications used after transplantation have significant toxicities. Foxp3(+) T-regulatory cells can prevent allograft rejection without compromising protective host immunity. Interestingly, inhibiting the class III histone/protein deacetylase Sirtuin-1 can augment Foxp3(+) T-regulatory suppressive function through increasing Foxp3 acetylation. Here we determined whether Sirtuin-1 targeting can stabilize biological allograft function. BALB/c kidney allografts were transplanted into C57BL/6 recipients with a CD4-conditional deletion of Sirtuin-1 (Sirt1(fl/fl)CD4(cre)) or mice treated with a Sirtuin-1-specific inhibitor (EX-527), and the native kidneys removed. Blood chemistries and hematocrit were followed weekly. Sirt1(fl/fl)CD4(cre) recipients showed markedly longer survival and improved kidney function. Sirt1(fl/fl)CD4(cre) recipients exhibited donor-specific tolerance, accepted BALB/c, but rejected third-party C3H cardiac allografts. C57BL/6 recipients of BALB/c renal allografts that were treated with EX-527 showed improved survival and renal function at 1, but not 10 mg/kg/day. Pharmacologic inhibition of Sirtuin-1 also improved renal allograft survival and function with dosing effects having relevance to outcome. Thus, inhibiting Sirtuin-1 can be a useful asset in controlling T-cell-mediated rejection. However, effects on non-T cells that could adversely affect allograft survival and function merit consideration.

  3. Allograft selection for distal femur through cutting contour registration.

    PubMed

    Qiu, Lei; Zhang, Yu; Zhang, Qing; Xu, Lihui; Niu, Xiaohui; Zhang, Li

    2016-12-01

    Allograft reconstruction is an acceptable procedure for the recovery of normal anatomy after the bone tumor resection. During the past few years, several automated methods have been proposed to select the best anatomically matching allograft from the virtual donor bone bank. The surface-based automated method uses the contralateral healthy bone to obtain the normal surface shape of the diseased bone, which could achieve good matching of the defect and the selected allograft. However, the surface-based method focuses on the matching of the whole bone so that the matching of the contact surface between the allograft and the recipient bone may not be optimal. To deal with the above problem, we propose a cutting contour based method for the allograft selection. Cutting contour from the recipient bone could reflect the structural information of the defect and is seldom influenced by tumor. Thus the cutting contour can be used as the matching template to find the optimal alignment of the recipient bone and the allograft. The proposed method is validated using the data of distal femurs where bone transplantation is commonly performed. Experimental results show that the proposed method generally outperforms the surface-based method within modest extra time. Overall, our contour-based method is an effective complementary technique for allograft selection in the virtual bone bank.

  4. High-pressure saline washing of allografts reduces bacterial contamination.

    PubMed

    Hirn, M Y; Salmela, P M; Vuento, R E

    2001-02-01

    60 fresh-frozen bone allografts were contaminated on the operating room floor. No bacterial growth was detected in 5 of them after contamination. The remaining 55 grafts had positive bacterial cultures and were processed with three methods: soaking in saline, soaking in antibiotic solution or washing by high-pressure saline. After high-pressure lavage, the cultures were negative in three fourths of the contaminated allografts. The corresponding figures after soaking grafts in saline and antibiotic solution were one tenth and two tenths, respectively. High-pressure saline cleansing of allografts can be recommended because it improves safety by reducing the superficial bacterial bioburden.

  5. Involvement of the Cav3.2 T-type calcium channel in thalamic neuron discharge patterns

    PubMed Central

    2011-01-01

    Background Mice that have defects in their low-threshold T-type calcium channel (T-channel) genes show altered pain behaviors. The changes in the ratio of nociceptive neurons and the burst firing property of reticular thalamic (RT) and ventroposterior (VP) neurons in Cav3.2 knockout (KO) mice were studied to test the involvement of thalamic T-channel and burst firing activity in pain function. Results Under pentobarbital or urethane anesthesia, the patterns of tonic and burst firings were recorded in functionally characterized RT and VPL neurons of Cav3.2 KO mice. Many RT neurons were nociceptive (64% under pentobarbital anesthesia and 50% under urethane anesthesia). Compared to their wild-type (WT) controls, fewer nociceptive RT neurons were found in Cav3.2 KO mice. Both nociceptive and tactile RT neurons showed fewer bursts in Cav3.2 KO mice. Within a burst, RT neurons of Cav3.2 KO mice had a lower spike frequency and less-prominent accelerando-decelerando change. In contrast, VP neurons of Cav3.2 KO mice showed a higher ratio of bursts and a higher discharge rate within a burst than those of the WT control. In addition, the long-lasting tonic firing episodes in RT neurons of the Cav3.2 KO had less stereotypic regularity than their counterparts in WT mice. Conclusions RT might be important in nociception of the mouse. In addition, we showed an important role of Cav3.2 subtype of T-channel in RT burst firing pattern. The decreased occurrence and slowing of the bursts in RT neurons might cause the increased VP bursts. These changes would be factors contributing to alternation of pain behavior in the Cav3.2 KO mice. PMID:21639922

  6. Caldendrin, a neuron-specific modulator of Cav/1.2 (L-type) Ca2+ channels.

    PubMed

    Tippens, Alyssa L; Lee, Amy

    2007-03-16

    EF-hand Ca2+-binding proteins such as calmodulin and CaBP1 have emerged as important regulatory subunits of voltage-gated Ca2+ channels. Here, we show that caldendrin, a variant of CaBP1 enriched in the brain, interacts with and distinctly modulates Cav1.2 (L-type) voltage-gated Ca2+ channels relative to other Ca2+-binding proteins. Caldendrin binds to the C-terminal IQ-domain of the pore-forming alpha1-subunit of Cav1.2 (alpha(1)1.2) and competitively displaces calmodulin and CaBP1 from this site. Compared with CaBP1, caldendrin causes a more modest suppression of Ca2+-dependent inactivation of Cav1.2 through a different subset of molecular determinants. Caldendrin does not bind to the N-terminal domain of alpha11.2, a site that is critical for functional interactions of the channel with CaBP1. Deletion of the N-terminal domain inhibits CaBP1, but spares caldendrin modulation of Cav1.2 inactivation. In contrast, mutations of the IQ-domain abolish physical and functional interactions of caldendrin and Cav1.2, but do not prevent channel modulation by CaBP1. Using antibodies specific for caldendrin and Cav1.2, we show that caldendrin coimmunoprecipitates with Cav1.2 from the brain and colocalizes with Cav1.2 in somatodendritic puncta of cortical neurons in culture. Our findings reveal functional diversity within related Ca2+-binding proteins, which may enhance the specificity of Ca2+ signaling by Cav1.2 channels in different cellular contexts.

  7. Contribution of electromechanical coupling between KV and CaV1.2 channels to coronary dysfunction in obesity

    PubMed Central

    Berwick, Zachary C.; Dick, Gregory M.; O’Leary, Heather A.; Bender, Shawn B.; Goodwill, Adam G.; Moberly, Steven P.; Owen, Meredith Kohr; Miller, Steven J.; Obukhov, Alexander G.

    2013-01-01

    Previous investigations indicate that diminished functional expression of voltage-dependent K+ (KV) channels impairs control of coronary blood flow in obesity/metabolic syndrome. The goal of this investigation was to test the hypothesis that KV channels are electromechanically coupled to CaV1.2 channels and that coronary microvascular dysfunction in obesity is related to subsequent increases in CaV1.2 channel activity. Initial studies revealed that inhibition of KV channels with 4-aminopyridine (4AP, 0.3 mM) increased intracellular [Ca2+], contracted isolated coronary arterioles and decreased coronary reactive hyperemia. These effects were reversed by blockade of CaV1.2 channels. Further studies in chronically instrumented Ossabaw swine showed that inhibition of CaV1.2 channels with nifedipine (10 μg/kg, iv) had no effect on coronary blood flow at rest or during exercise in lean swine. However, inhibition of CaV1.2 channels significantly increased coronary blood flow, conductance, and the balance between coronary flow and metabolism in obese swine (P < 0.05). These changes were associated with a ~50 % increase in inward CaV1.2 current and elevations in expression of the pore-forming subunit (α1c) of CaV1.2 channels in coronary smooth muscle cells from obese swine. Taken together, these findings indicate that electromechanical coupling between KV and CaV1.2 channels is involved in the regulation of coronary vasomotor tone and that increases in CaV1.2 channel activity contribute to coronary microvascular dysfunction in the setting of obesity. PMID:23856709

  8. Hyperglycemia-induced vasculopathy in the murine vitelline vasculature: correlation with PECAM-1/CD31 tyrosine phosphorylation state.

    PubMed

    Pinter, E; Mahooti, S; Wang, Y; Imhof, B A; Madri, J A

    1999-05-01

    Maternal diabetes mellitus is associated with an increased incidence of congenital abnormalities as well as embryonic and perinatal lethality. In particular, a wide range of cardiovascular abnormalities have been noted in children of diabetic mothers and in the offspring of diabetic animals. The vascular system is the first organ system to develop in the embryo and is critical for normal organogenesis. The organization of mesodermal cells into endothelial and hematopoietic cells and into a complex vascular system is, in part, mediated by a series of specific cell-cell, cell-extracellular matrix, and cell-factor interactions. PECAM-1 expression has been observed during the earliest stages of vasculogenesis, and changes in PECAM-1 tyrosine phosphorylation have been associated with endothelial cell migration, vasculogenesis, and angiogenesis both in vitro and in vivo. In this report we demonstrate that exposure to hyperglycemia during gastrulation causes yolk sac and embryonic vasculopathy in cultured murine conceptuses and in the conceptuses of streptozotocin-induced diabetic pregnant mice. In addition, we correlate the presence of yolk sac and embryonic vasculopathy with the failure of PECAM-1 tyrosine dephosphorylation during the formation of blood islands/vessels from clusters of extra-embryonic and embryonic angioblasts in the murine conceptus using both in vitro and in vivo models. The importance of these findings in the development of vasculopathy in the offspring of diabetic mothers and the potential effects and benefits of glucose regulation during the periods of vasculogenesis/angiogenesis in embryonic development are discussed.

  9. Similar molecular determinants on Rem mediate two distinct modes of inhibition of CaV1.2 channels

    PubMed Central

    Puckerin, Akil A.; Chang, Donald D.; Subramanyam, Prakash; Colecraft, Henry M.

    2016-01-01

    ABSTRACT Rad/Rem/Rem2/Gem (RGK) proteins are Ras-like GTPases that potently inhibit all high-voltage-gated calcium (CaV1/CaV2) channels and are, thus, well-positioned to tune diverse physiological processes. Understanding how RGK proteins inhibit CaV channels is important for perspectives on their (patho)physiological roles and could advance their development and use as genetically-encoded CaV channel blockers. We previously reported that Rem can block surface CaV1.2 channels in 2 independent ways that engage distinct components of the channel complex: (1) by binding auxiliary β subunits (β-binding-dependent inhibition, or BBD); and (2) by binding the pore-forming α1C subunit N-terminus (α1C-binding-dependent inhibition, or ABD). By contrast, Gem uses only the BBD mechanism to block CaV1.2. Rem molecular determinants required for BBD CaV1.2 inhibition are the distal C-terminus and the guanine nucleotide binding G-domain which interact with the plasma membrane and CaVβ, respectively. However, Rem determinants for ABD CaV1.2 inhibition are unknown. Here, combining fluorescence resonance energy transfer, electrophysiology, systematic truncations, and Rem/Gem chimeras we found that the same Rem distal C-terminus and G-domain also mediate ABD CaV1.2 inhibition, but with different interaction partners. Rem distal C-terminus interacts with α1C N-terminus to anchor the G-domain which likely interacts with an as-yet-unidentified site. In contrast to some previous studies, neither the C-terminus of Rem nor Gem was sufficient to inhibit CaV1/CaV2 channels. The results reveal that similar molecular determinants on Rem are repurposed to initiate 2 independent mechanisms of CaV1.2 inhibition. PMID:27115600

  10. Allelic and Epitopic Characterization of Intra-Kidney Allograft Anti-HLA Antibodies at Allograft Nephrectomy.

    PubMed

    Milongo, D; Kamar, N; Del Bello, A; Guilbeau-Frugier, C; Sallusto, F; Esposito, L; Dörr, G; Blancher, A; Congy-Jolivet, N

    2017-02-01

    The reasons for the increased incidence of de novo anti-human leukocyte antibody (HLA) donor-specific antibodies (DSAs) observed after kidney allograft nephrectomy are not fully understood. One advocated mechanism suggests that at graft loss, DSAs are not detected in the serum because they are fixed on the nonfunctional transplant; removal of the kidney allows DSAs to then appear in the blood circulation. The aim of our study was to compare anti-HLA antibodies present in the serum and in the graft at the time of an allograft nephrectomy. Using solid-phase assays, anti-HLA antibodies were searched for in the sera of 17 kidney transplant patients undergoing allograft nephrectomy. No anti-HLA antibodies were detected in the graft if they were not also detected in the serum. Eleven of the 12 patients who had DSAs detected in their sera also had DSAs detected in the grafts. Epitopic analysis revealed that most anti-HLA antibodies detected in removed grafts were directed against the donor. In summary, our data show that all anti-HLA antibodies that were detected in grafts were also detected in the sera. These intragraft anti-HLA antibodies are mostly directed against the donor at an epitopic level but not always at an antigenic level.

  11. [Hand allografts: experience from Lyon team].

    PubMed

    Gazarian, A; Abrahamyan, D-O; Petruzzo, P; Kanitakis, J; Guigal, V; Garret, J; Rizzo, C; Durand, P-Y; Fredenucci, J-F; Streichenberger, T; Parmentier, H; Galewicz, T; Guillot, M; Sirigu, A; Burloux, G; Morelon, E; Braye, F; Badet, L; Martin, X; Dubernard, J-M; Eljaafari, A

    2007-10-01

    Hand allograft is a method in the stage of clinical experimentation, which is reserved in France for the treatment of bilateral traumatic amputees. This study reports the Lyon team experience, which is pioneer in this domain. Four patients (3 males and 1 female) underwent seven (one unilateral and three bilateral) hand transplantations from September 1998 to February 2007. The level of amputation was at the wrist or at the mid-forearm. Delay since hand loss ranged from 2.5 to 9 years. The surgical protocol was elaborated and planned case by case. All recipients received the same immunosuppressive treatment. Episodes of acute rejection were observed in the first 3 months after transplantation, which were easily managed after a few days increasing oral prednisone doses and applying topical immunosuppressants. Currently the patients receive the doses of immunosuppressants comparable to those in kidney-grafted patients. We have not registered any severe complication of immunosuppressive treatment up till now (7 years follow-up for the earliest graft). We performed analytical and functional clinical, as well as questionnaire evaluation of patients. The first case (unilateral graft) resulted in graft failure at 2 years due to non-compliance of the patient. The three bilateral graftees demonstrate a favorable evolution despite some immunological (hyperglycemia, serum sickness) and surgical (thrombosis, osteomyelitis, skin loss) complications, which could be managed. The middle and long-term follow-up evaluation revealed good to excellent sensorimotor recovery of 4 hands in both male recipients (4 and 7 years) with satisfactory social adaptation, higher or equal to those expected after post-traumatic replantations at the equivalent level and higher to those obtained with currently available myoelectric prosthesis. The last patient, a young female who has been grafted in February 2007, receives ongoing reeducation course and shows normal progress of functional restoration

  12. Multifocal bacterial osteomyelitis in a renal allograft recipient following urosepsis.

    PubMed

    Valson, A T; David, V G; Balaji, V; John, G T

    2014-05-01

    Non-tubercular bacterial osteomyelitis is a rare infection. We report on a renal allograft recipient with osteomyelitis complicating urosepsis, manifesting as a multifocal infection poorly responsive to appropriate antibiotics and surgical intervention and culminating in graft loss.

  13. Dysplasia Epiphysealis Hemimelica Treated with Osteochondral Allograft: A Case Report

    PubMed Central

    Anthony, Chris A.; Wolf, Brian R.

    2015-01-01

    Background Dysplasia epiphysealis hemimelica (DEH), or Trevor's disease, is a developmental disorder of the pediatric skeleton characterized by asymmetric osteochondral overgrowth. Methods We present the case of a five year old boy with a two year history of right knee pain and evidence of DEH on imaging who underwent initial arthroscopic resection of his lesion with subsequent recurrence. The patient then underwent osteochondral allograft revision surgery and was asymptomatic at two year follow-up with a congruent joint surface. Results To our knowledge, this is the first reported case of a DEH lesion treated with osteochondral allograft and also the youngest reported case of osteochondral allograft placement in the literature. Conclusions Osteochondral allograft may be a viable option in DEH and other deformities of the pediatric knee. Level of Evidence Level V PMID:26361443

  14. A Phase II Multicenter Trial With Rivaroxaban in the Treatment of Livedoid Vasculopathy Assessing Pain on a Visual Analog Scale

    PubMed Central

    Drabik, Attyla; Hillgruber, Carina

    2014-01-01

    Background Livedoid vasculopathy is an orphan skin disease characterized by recurrent thrombosis of the cutaneous microcirculation. It manifests itself almost exclusively in the ankles, the back of the feet, and the distal part of the lower legs. Because of the vascular occlusion, patients suffer from intense local ischemic pain. Incidence of livedoid vasculopathy is estimated to be around 1:100,000. There are currently no approved treatments for livedoid vasculopathy, making off-label therapy the only option. In Europe, thromboprophylactic treatment with low-molecular-weight heparins has become widely accepted. Objective The aim of this trial is the statistical verification of the therapeutic effects of the anticoagulant rivaroxaban in patients suffering from livedoid vasculopathy. Methods We performed a therapeutic phase IIa trial designed as a prospective, one-armed, multicenter, interventional series of cases with a calculated sample size of 20 patients. The primary outcome is the assessment of local pain on the visual analog scale (VAS) as an intraindividual difference of 2 values between baseline and 12 weeks. Results Enrollment started in December 2012 and was still open at the date of submission. The study is expected to finish in November 2014. Conclusions Livedoid vasculopathy is associated with increased thrombophilia in the cutaneous microcirculation and the continuous use of anticoagulants helps improve the symptoms. The causes of cutaneous infarctions are heterogenous, but ultimately follow the known mechanisms of the coagulation cascade. Rivaroxaban affects the coagulation cascade and inhibits the factor Xa–dependent conversion of prothrombin to thrombin, thereby considerably reducing the risk of thrombosis. Trial Registration Trial Registration EudraCT Number: 2012-000108-13-DE; https://www.clinicaltrialsregister.eu/ctr-search/search?query=eudract_number:2012-000108-13 (Archived by WebCite at http://www.webcitation.org/6UCktWVCA); German Clinical

  15. Allorecognition by T Lymphocytes and Allograft Rejection

    PubMed Central

    Marino, Jose; Paster, Joshua; Benichou, Gilles

    2016-01-01

    Recognition of donor antigens by recipient T cells in secondary lymphoid organs initiates the adaptive inflammatory immune response leading to the rejection of allogeneic transplants. Allospecific T cells become activated through interaction of their T cell receptors with intact allogeneic major histocompatibility complex (MHC) molecules on donor cells (direct pathway) and/or donor peptides presented by self-MHC molecules on recipient antigen-presenting cells (APCs) (indirect pathway). In addition, recent studies show that alloreactive T cells can also be stimulated through recognition of allogeneic MHC molecules displayed on recipient APCs (MHC cross-dressing) after their transfer via cell–cell contact or through extracellular vesicles (semi-direct pathway). The specific allorecognition pathway used by T cells is dictated by intrinsic and extrinsic factors to the allograft and can influence the nature and magnitude of the alloresponse and rejection process. Consequently, various organs and tissues such as skin, cornea, and solid organ transplants are recognized differently by pro-inflammatory T cells through these distinct pathways, which may explain why these grafts are rejected in a different fashion. On the other hand, the mechanisms by which anti-inflammatory regulatory T cells (Tregs) recognize alloantigen and promote transplantation tolerance are still unclear. It is likely that thymic Tregs are activated through indirect allorecognition, while peripheral Tregs recognize alloantigens in a direct fashion. As we gain insights into the mechanisms underlying allorecognition by pro-inflammatory and Treg cells, novel strategies are being designed to prevent allograft rejection in the absence of ongoing immunosuppressive drug treatment in patients. PMID:28018349

  16. Tuberculosis in a renal allograft: a successful outcome.

    PubMed

    George, Pratish; Pawar, Basant; Calton, Nalini

    2008-09-01

    Tuberculosis is endemic in most South-East Asian countries including India. It causes significant morbidity and mortality in renal transplant recipients and often, it is not diagnosed early, due to its innocuous clinical presentations. A high index of suspicion and proactive management in the early phase of presentation can reduce allograft nephropathy, graft nephrectomy and mortality. A patient with an unusual presentation of tuberculosis localized to the allograft and successful management with anti-tuberculosis medications is described.

  17. Treatment of allograft nonunions with recombinant human bone morphogenetic proteins (rhBMP).

    PubMed

    Delloye, Christian; Suratwala, Sanjeev J; Cornu, Olivier; Lee, Francis Y

    2004-12-01

    Fractures and nonunions are the main complications associated with bone allografts. Although the osteogenic role of recombinant human bone morphogenetic proteins (rhBMPs) has been demonstrated in experimental models and human tibial nonunions, the results are unknown for allograft nonunions. In this study, the efficacy of rhBMPs was evaluated in nonunions of femoral allografts. The results of six allograft nonunions in five patients who underwent resection of malignant bone tumours and allograft bone transplantation were analysed one to five years following application of rhBMPs at the nonunion site. There were two osteoarticular allografts and three intercalary allografts. Of three intercalary allografts, one demonstrated nonunion at both ends. Four patients received adjuvant chemotherapy and three had additional radiation therapy. There were two allograft fracture nonunions and four nonunions at the allograft-host junction. Two allograft fracture nonunions and one nonunion at the allograft-host junction were treated with 12 mg of rhBMP-2. The remaining three nonunions were treated with 7 mg of rhBMP-7 (Osigraft). The outcome and radiological evidence of healing were evaluated at a minimal follow-up of twelve months. There was neither healing of allograft fractures nor union of allograft-host junction. There was elongation or enlargement of the callus from the host. One patient continued to develop resorption of the allograft, which led to allograft fracture. Two patients who were treated with rhBMP-7 and corticocancellous allografts developed sterile drainage. There was no tumour recurrence with the use of rhBMPs after a mean follow-up of 39+/-25 months. rhBMP's alone were not sufficient to achieve healing in allograft nonunions and fractures following wide resection including periosteum and soft tissues.

  18. C-Terminal Modulatory Domain Controls Coupling of Voltage-Sensing to Pore Opening in Cav1.3 L-type Ca2+ Channels

    PubMed Central

    Lieb, Andreas; Ortner, Nadine; Striessnig, Jörg

    2014-01-01

    Activity of voltage-gated Cav1.3 L-type Ca2+ channels is required for proper hearing as well as sinoatrial node and brain function. This critically depends on their negative activation voltage range, which is further fine-tuned by alternative splicing. Shorter variants miss a C-terminal regulatory domain (CTM), which allows them to activate at even more negative potentials than C-terminally long-splice variants. It is at present unclear whether this is due to an increased voltage sensitivity of the Cav1.3 voltage-sensing domain, or an enhanced coupling of voltage-sensor conformational changes to the subsequent opening of the activation gate. We studied the voltage-dependence of voltage-sensor charge movement (QON-V) and of current activation (ICa-V) of the long (Cav1.3L) and a short Cav1.3 splice variant (Cav1.342A) expressed in tsA-201 cells using whole cell patch-clamp. Charge movement (QON) of Cav1.3L displayed a much steeper voltage-dependence and a more negative half-maximal activation voltage than Cav1.2 and Cav3.1. However, a significantly higher fraction of the total charge had to move for activation of Cav1.3 half-maximal conductance (Cav1.3: 68%; Cav1.2: 52%; Cav3.1: 22%). This indicated a weaker coupling of Cav1.3 voltage-sensor charge movement to pore opening. However, the coupling efficiency was strengthened in the absence of the CTM in Cav1.342A, thereby shifting ICa-V by 7.2 mV to potentials that were more negative without changing QON-V. We independently show that the presence of intracellular organic cations (such as n-methyl-D-glucamine) induces a pronounced negative shift of QON-V and a more negative activation of ICa-V of all three channels. These findings illustrate that the voltage sensors of Cav1.3 channels respond more sensitively to depolarization than those of Cav1.2 or Cav3.1. Weak coupling of voltage sensing to pore opening is enhanced in the absence of the CTM, allowing short Cav1.342A splice variants to activate at lower voltages

  19. Ammonium Increases TRPC1 Expression Via Cav-1/PTEN/AKT/GSK3β Pathway.

    PubMed

    Wang, Wei; Gu, Li; Verkhratsky, Alexei; Peng, Liang

    2017-03-01

    Hyperammonemia occurring following acute liver failure is the primary cause of hepatic encephalopathy. In the brain, ammonium is catabolised by glutamine synthetase expressed exclusively in astroglia; ammonium overload impairs astroglial homeostatic systems. Previously, we had reported that chronic treatment with 3 mM ammonia increased expression of transient receptor potential canonic 1 (TRPC1) channels and Ca(2+) release from intracellular Ca(2+) stores (Liang et al. in Neurochem Res 39:2127-2135, 2014). Glycogen synthase kinase 3β (GSK-3β) has a key role in several astroglial signalling pathways and is known to be affected in various CNS diseases. We have studied the involvement of Cav-1/PTEN/AKT/GSK-3β signalling system in regulation of TRPC1 gene expression by ammonium. Effects of chronic (1-5 days) treatment with ammonium chloride (ammonium), at pathologically relevant concentrations of 1-5 mM were investigated on primary cultures of mouse cerebral astrocytes. We quantified expression of caveolin-1 (Cav-1), membrane content of phosphatase and tensin homologue (PTEN), phosphorylation of AKT and GSK-3β, and expression of TRPC1 channels. Ammonium significantly increased expression of Cav-1 mRNA and protein, mRNA of TRPC1 as well as membrane content of PTEN; conversely phosphorylation of AKT and GSK-3β were significantly decreased. These changes were abolished following astrocytes treatment with siRNA specific to Cav-1, indicating the involvement of Cav-1/PTEN/PI3K/AKT pathway. Similar results were found in the brains of adult mice subjected to intraperitoneal injection of urease (a model for hyperammoniemia) for 1-5 days. In transgenic mice tagged with an astrocyte-specific or neurone-specific markers (used for fluorescence-activated cell sorting of astrocytes vs. neurones) and treated with intraperitoneal injections of urease for 3 days, the Cav-1 gene mRNA expression was up-regulated in astrocytes, but not in neurones. The up-regulation of TRPC1 gene

  20. Erythroblast transformation-specific 2 correlates with vascular smooth muscle cell apoptosis in rat heterotopic heart transplantation model

    PubMed Central

    Liu, Xiaojuan; Yan, Daliang; Li, Yangcheng; Sha, Xilin; Wu, Kunpeng; Zhao, Jianhua; Yang, Chen; Zhang, Chao

    2016-01-01

    Background Cardiac allograft vasculopathy (CAV) decreases the long-term survival of heart transplantation recipients. Vascular smooth muscle cell (VSMC) apoptosis is an important pathological feature of CAV. Erythroblast transformation-specific 2 (Ets-2), as a transcription factor, participates in cell apoptosis and plays an important role in organ transplantation. Methods Hearts from Wistar-Furth (WF:RT1u) rats were heterotopically transplanted into Lewis (Lew:RT1l) rats without immunosuppression. Additional syngeneic heterotopic cardiac transplantations were performed in Lewis rats. HE staining was used to identify CAV. Ets-2 expression was examined by western blot. Ets-2 tissue location was examined by immunohistochemical assay and double immunostaining. Cleaved caspase 3 expression was detected by western blot. Co-localization of Ets-2 and cleaved caspase 3 was detected by double immunostaining. Ets-2, p53, cleaved caspase 3 and Bcl-xl expression in rat VSMC line A7R5 was examined after Ets-2 siRNA transfection. TUNEL assay was applied to detect A7R5 apoptosis with or without ETS-2 siRNA transfection. Immunoprecipitation was performed to explore the interaction between Ets-2 and p53. Results Ets-2 expression decreased in the allograft group but had no obvious change in the isograft group. Meanwhile, the phenomenon of CAV was observed in the allograft group and there is neointima formation in the isograft group which is not obvious compared with allograft group. Additionally, Ets-2 expression was opposite to VSMC apoptosis in the allograft group. In vitro, Ets-2 siRNA transfection in A7R5cells resulted in enhanced cell apoptosis. Finally, Ets-2 interacted with p53. Conclusions Ets-2 might inhibit VSMC apoptosis via p53 pathway. The results further elucidate the molecular mechanism of VSMC apoptosis after heart transplantation during CAV and provide theoretical basis for seeking new specific drug targets for CAV prevention and treatment. PMID:27621856

  1. Acute angle closure glaucoma secondary to polypoidal choroidal vasculopathy – a devastating complication

    PubMed Central

    Baskaran, Prabu; Sindal, Manavi D.; Dhoble, Pankaja; Ramakrishnan, Seema; Rengaraj, Venkatesh; Ramulu, Pradeep

    2017-01-01

    Acute angle closure glaucoma (ACG) in the setting of polypoidal choroidal vasculopathy (PCV) is a catastrophic complication that has been documented infrequently in literature. Ours is the second only report that describes hemorrhagic choroidal detachment as an event leading to acute angle closure glaucoma in PCV patients and the first one to describe the use of diode cyclophotocoagulation (CPC) for this condition. The purpose of this article is to familiarize readers with this entity that has an extremely dismal visual prognosis. Ours is a descriptive case report of two patients with PCV complicated by sudden onset hemorrhagic choroidal detachment (CD) and acute ACG. Both patients had severe pain with no perception of light at presentation with an acute angle closure attack. Both underwent diode CPC for pain relief and control of intraocular pressure (IOP). Both our patients did not regain any vision, but their pain was relieved by diode CPC. Both eyes eventually became phthisical. Acute ACG following massive hemorrhagic CD is a rare but grave complication of PCV, not amenable to treatment. Diode CPC is an effective palliative modality of management to achieve pain relief in such cases. PMID:28154791

  2. Establishing 3-nitrotyrosine as a biomarker for the vasculopathy of Fabry disease

    PubMed Central

    Shu, Liming; Vivekanandan-Giri, Anuradha; Pennathur, Subramaniam; Smid, Bouwien E; Aerts, Johannes M FG; Hollak, Carla E M; Shayman, James A

    2014-01-01

    The endothelial dysfunction of Fabry disease results from α-galactosidase A deficiency leading to the accumulation of globotriaosylceramide. Vasculopathy in the α-galactosidase A null mouse is manifested as oxidant-induced thrombosis, accelerated atherogenesis, and impaired arterial reactivity. To better understand the pathogenesis of Fabry disease in humans, we generated a human cell model by using RNA interference. Hybrid endothelial cells were transiently transfected with small interfering RNA (siRNA) specifically directed against α-galactosidase A. Knockdown of α-galactosidase A was confirmed using immunoblotting and globotriaosylceramide accumulation. Endothelial nitric oxide synthase (eNOS) activity was correspondingly decreased by >60%. Levels of 3-nitrotyrosine (3NT), a specific marker for reactive nitrogen species and quantified using mass spectrometry, increased by 40- to 120-fold without corresponding changes in other oxidized amino acids, consistent with eNOS-derived reactive nitrogen species as the source of the reactive oxygen species. eNOS uncoupling was confirmed by the observed increase in free plasma and protein-bound aortic 3NT levels in the α-galactosidase A knockout mice. Finally, 3NT levels, assayed in biobanked plasma samples from patients with classical Fabry disease, were over sixfold elevated compared with age- and gender-matched controls. Thus, 3NT may serve as a biomarker for the vascular involvement in Fabry disease. PMID:24402087

  3. Effect of transfusion therapy on cerebral vasculopathy in children with sickle-cell anemia

    PubMed Central

    Bader-Meunier, Brigitte; Verlhac, Suzanne; Elmaleh-Bergès, Monique; Ithier, Ghislaine; Sellami, Fatiha; Faid, Sonia; Missud, Florence; Ducrocq, Rolande; Alberti, Corinne; Zaccaria, Isabelle; Baruchel, Andre; Benkerrou, Malika

    2009-01-01

    This retrospective study assessed the long-term effect of transfusional exchange therapy on MRA/MRI abnormalities in 24 homozygous sickle-cell anemia (HbSS) children presenting with abnormal brain MRA. The median time elapsed from baseline to last available MRA was 29 months. Follow-up MRAs showed improvement, stabilization or worsening of cerebrovascular lesions in 11, 6 and 7 patients respectively. Complete normalization of MRA was observed in 6 patients within a mean time of 1.4 years, but stenosis recurred at the same location in the 4 patients in whom transfusion therapy was discontinued. Baseline severe stenosis/occlusion of large cerebral arteries and occurrence of moyamoya syndrome were significantly associated with an absence of improvement of the cerebral vasculopathy. These data emphasize the heterogeneity of the course of cerebrovasculopathy in SS children receiving chronic transfusion. Further studies are needed to determine whether different therapeutic approaches have to be considered according to these different evolutive patterns in SS children. PMID:19059938

  4. Responsiveness of eyes with polypoidal choroidal vasculopathy with choroidal hyperpermeability to intravitreal ranibizumab

    PubMed Central

    2013-01-01

    Background To determine the role played by vascular endothelial growth factor (VEGF) in polypoidal choroidal vasculopathy (PCV) based on an interventional immunology theory. Methods Eyes with PCV were divided in a masked fashion into those with choroidal hyperpermeability (HP group) and those with normal choroidal permeability (NP group) based on the indocyanine green angiograms. The inter-rater agreement rate was evaluated using Fleiss’ kappa. Patients were treated by intravitreal ranibizumab (IVB). The central choroidal thickness and central foveal thickness (CFT) at the baseline and 7 days after the treatment were measured by optical coherence tomography. Results Among the 57 consecutive eyes diagnosed with PCV, 42 eyes of 42 patients met the inclusion criteria (21 eyes/HP group vs 21 eyes /NP group). Central choroidal thickness in HP group was significantly thicker than that in the NP group (P < .001, Mann–Whitney U test). The inter-rater agreement was high with a Fleiss’ kappa = 0.95, P < .0001. The percentage reduction in the CFT in HP group (14.0%) was significantly less than that in NP group (20.4%; P = .013, Mann–Whitney U test). Conclusions Eyes with PCV that are associated with choroidal hyper-permeability may not be strongly associated with VEGF-related pathology, and may not respond favorably to anti-VEGF monotherapy. PMID:23962072

  5. A glycation angle to look into the Diabetic Vasculopathy: Cause and Cure.

    PubMed

    Ahmad, Saheem; Siddiqui, Zeba; Rehman, Shahnawaz; Khan, Mohd Yasir; Khan, Hamda; Khanum, Sheeba; Alouffi, Sultan; Saeed, Mohd

    2017-03-27

    The process of advanced glycation, which is accelerated in diabetes as a result of chronic hyperglycemia and increased oxidative stress, has been suggested to play a vital role in the diabetic complications. Extensive intracellular and extracellular generation and accumulation of advanced glycation end products (AGEs) have been linked to increased risk for microvascular and macrovascular injuries in diabetes. AGEs result from the nonenzymatic reaction of reducing sugars with proteins, lipids, and nucleic acids, potentially altering their function. AGEs act directly to induce cross-linking of long-lived proteins to promote vascular stiffness, and, thus, alter vascular structure and function. AGEs may also activate specific receptors, like the receptor for AGEs (RAGEs), to induce intracellular signaling that leads to enhanced oxidative stress and amplification of key proinflammatory and prosclerotic cytokines. Over the last decade, a large number of preclinical studies have been performed, targeting the formation and degradation of AGEs, as well as the interaction of AGEs with RAGEs. This review focuses on how these AGEs may exert injurious effects in diabetes, as well as address current strategies to interrupt the formation or action of AGEs. Because of the potential role of early- and advanced glycation in diabetic vasculopathy, we also described recent developments of pharmacological inhibitors that inhibit the biological consequences of glycation and thereby retard the development of vascular complications in diabetes.

  6. Idiopathic polypoidal choroidal vasculopathy in Thai patients with clinical and angiographic choroidal neovascularization

    PubMed Central

    Bhoomibunchoo, Chavakij; Yospaiboon, Yosanan; Thoongsuwan, Somanus; Rojanaporn, Duangnate; Watanachai, Nawat; Jirarattanasopa, Pichai; Wongcumchang, Nattapon; Amphornphruet, Atchara; Vongkulsiri, Sritatath; Arayangkoon, Eakkachai

    2017-01-01

    Objective This study aimed to study the prevalence and characteristics of idiopathic polypoidal choroidal vasculopathy (IPCV) in Thai patients with clinical and angiographic choroidal neovascularization (CNV). Patients and methods A consecutive case study of 140 patients presenting with CNV was conducted in nine large referral eye centers throughout Thailand. The demographic data, fundus photographs, fundus fluorescein angiography and indocyanine green angiography of the patients were analyzed. Results Of 129 patients with clinical and angiographic CNV, IPCV was diagnosed in 100 patients (77.52%), idiopathic CNVs in 16 patients (12.40%) and age-related macular degeneration (AMD) in 12 patients (9.30%). Of the 107 eyes with IPCV, 90 eyes (84.11%) had both branching venous networks (BVNs) and polypoidal lesions. Most IPCV patients (93%) had unilateral involvement and were at a younger age than AMD patients. In all, 79 eyes (73.83%) had lesions found in the macular area, 14 eyes (13.08%) in the temporal to vascular arcades, ten eyes (9.35%) in the peripapillary area and four eyes (3.74%) in both macular and peripapillary areas. The clinical manifestations of IPCV at presentation were categorized into two patterns. There were 95 eyes (88.79%) of a hemorrhagic pattern and 12 eyes (11.21%) of an exudative pattern. Conclusion IPCV is the most common macular disease in Thai patients with CNV. Most IPCVs have both BVNs and polypoidal lesions located in the macular area and present with a hemorrhagic pattern. PMID:28223776

  7. Noninflammatory necrotizing vasculopathy in lupus nephritis: a single-center experience.

    PubMed

    Chu, H; Wu, L H; Song, D; Yu, F; Zhao, M H

    2014-01-01

    In this study, we assessed the clinicopathological features of lupus nephritis patients with renal noninflammatory necrotizing vasculopathy (NNV). A total of 142 renal biopsies with lupus nephritis were reviewed, including nine cases presented with NNV and 36 without renal vascular lesions. The comparisons of clinical, laboratory and pathological features, treatments, as well as renal outcome between the two groups were further performed. In comparison with the no renal vascular lesions group, patients with NNV changes had significantly higher proportions of noninfection leukocyturia (p = 0.013) and leukocytopenia (p = 0.042), significantly higher serum creatinine (p = 0.012), lower hemoglobin (p = 0.002) and serum C3 (p < 0.001) levels. Renal pathological activity indices and chronicity indices were significantly higher in the NNV group (p = 0.002 and p = 0.006, respectively) than those in the no vascular lesions group. Regarding renal prognosis, the presence of NNV was not a risk factor for renal outcome (p = 0.327). In conclusion, NNV was not infrequent in renal biopsies of lupus nephritis. It was commonly associated with active clinical status and proliferative glomerular lesions of lupus.

  8. Incidence and significance of intrarenal vasculopathies in patients with systemic lupus erythematosus.

    PubMed

    Tsumagari, T; Fukumoto, S; Kinjo, M; Tanaka, K

    1985-01-01

    A clinicopathologic autopsy study of the vascular changes in the kidneys of 100 patients with systemic lupus erythematosus was undertaken. Necrotizing arteritis was found in seven patients, mucinous intimal thickening in nine, onion-skin intimal thickening in two, and renal vein thrombosis in two. Active necrotizing arteritis was present most frequently in the arterioles and interlobular arteries, with healing necrotizing arteritis predominating in the arcuate and interlobar arteries. These events were closely related to the activity of glomerular lesions, and immunologic vascular injury seemed to be the causative factor. Rapidly progressive renal failure and severe hypertension had characterized the clinical courses of the patients. Mucinous intimal thickening, present in the arterioles and interlobular arteries, had been accompanied by accelerated hypertension. Although dialysis or accelerated hypertension may have been causes, other factors, including glucocorticoid therapy, must be considered. In one patient with class II lupus nephritis, renal vein thrombosis was considered the cause of the nephrotic syndrome. These vasculopathies, often detected in patients with lupus at autopsy, seem to alter the clinical course.

  9. Ca2+ entry into neurons is facilitated by cooperative gating of clustered CaV1.3 channels

    PubMed Central

    Moreno, Claudia M; Dixon, Rose E; Tajada, Sendoa; Yuan, Can; Opitz-Araya, Ximena; Binder, Marc D; Santana, Luis F

    2016-01-01

    CaV1.3 channels regulate excitability in many neurons. As is the case for all voltage-gated channels, it is widely assumed that individual CaV1.3 channels behave independently with respect to voltage-activation, open probability, and facilitation. Here, we report the results of super-resolution imaging, optogenetic, and electrophysiological measurements that refute this long-held view. We found that the short channel isoform (CaV1.3S), but not the long (CaV1.3L), associates in functional clusters of two or more channels that open cooperatively, facilitating Ca2+ influx. CaV1.3S channels are coupled via a C-terminus-to-C-terminus interaction that requires binding of the incoming Ca2+ to calmodulin (CaM) and subsequent binding of CaM to the pre-IQ domain of the channels. Physically-coupled channels facilitate Ca2+ currents as a consequence of their higher open probabilities, leading to increased firing rates in rat hippocampal neurons. We propose that cooperative gating of CaV1.3S channels represents a mechanism for the regulation of Ca2+ signaling and electrical activity. DOI: http://dx.doi.org/10.7554/eLife.15744.001 PMID:27187148

  10. A novel CaV2.2 channel inhibition by piracetam in peripheral and central neurons.

    PubMed

    Bravo-Martínez, Jorge; Arenas, Isabel; Vivas, Oscar; Rebolledo-Antúnez, Santiago; Vázquez-García, Mario; Larrazolo, Arturo; García, David E

    2012-10-01

    No mechanistic actions for piracetam have been documented to support its nootropic effects. Voltage-gated calcium channels have been proposed as a promising pharmacological target of nootropic drugs. In this study, we investigated the effect of piracetam on Ca(V)2.2 channels in peripheral neurons, using patch-clamp recordings from cultured superior cervical ganglion neurons. In addition, we tested if Ca(V)2.2 channel inhibition could be related with the effects of piracetam on central neurons. We found that piracetam inhibited native Ca(V)2.2 channels in superior cervical ganglion neurons in a dose-dependent manner, with an IC(50) of 3.4 μmol/L and a Hill coefficient of 1.1. GDPβS dialysis did not prevent piracetam-induced inhibition of Ca(V)2.2 channels and G-protein-coupled receptor activation by noradrenaline did not occlude the piracetam effect. Piracetam altered the biophysical characteristics of Ca(V)2.2 channel such as facilitation ratio. In hippocampal slices, piracetam and ω-conotoxin GVIA diminished the frequency of excitatory postsynaptic potentials and action potentials. Our results provide evidence of piracetam's actions on Ca(V)2.2 channels in peripheral neurons, which might explain some of its nootropic effects in central neurons.

  11. Troponin T3 regulates nuclear localization of the calcium channel Cavβ1a subunit in skeletal muscle

    PubMed Central

    Zhang, Tan; Taylor, Jackson; Jiang, Yang; Pereyra, Andrea S.; Messi, Maria Laura; Wang, Zhong-Min; Hereñú, Claudia; Delbono, Osvaldo

    2015-01-01

    The voltage-gated calcium channel (Cav) β1a subunit (Cavβ1a) plays an important role in excitation-contraction coupling (ECC), a process in the myoplasm that leads to muscle-force generation. Recently, we discovered that the Cavβ1a subunit travels to the nucleus of skeletal muscle cells where it helps to regulate gene transcription. To determine how it travels to the nucleus, we performed a yeast two-hybrid screening of the mouse fast skeletal muscle cDNA library and identified an interaction with troponin T3 (TnT3), which we subsequently confirmed by co-immunoprecipitation and co-localization assays in mouse skeletal muscle in vivo and in cultured C2C12 muscle cells. Interacting domains were mapped to the leucine zipper domain in TnT3 COOH-terminus (160-244 aa) and Cavβ1a NH2-terminus (1-99 aa), respectively. The double fluorescence assay in C2C12 cells co-expressing TnT3/DsRed and Cavβ1a/YFP shows that TnT3 facilitates Cavβ1a nuclear recruitment, suggesting that the two proteins play a heretofore unknown role during early muscle differentiation in addition to their classical role in ECC regulation. PMID:25981458

  12. Troponin T3 regulates nuclear localization of the calcium channel Cavβ1a subunit in skeletal muscle.

    PubMed

    Zhang, Tan; Taylor, Jackson; Jiang, Yang; Pereyra, Andrea S; Messi, Maria Laura; Wang, Zhong-Min; Hereñú, Claudia; Delbono, Osvaldo

    2015-08-15

    The voltage-gated calcium channel (Cav) β1a subunit (Cavβ1a) plays an important role in excitation-contraction coupling (ECC), a process in the myoplasm that leads to muscle-force generation. Recently, we discovered that the Cavβ1a subunit travels to the nucleus of skeletal muscle cells where it helps to regulate gene transcription. To determine how it travels to the nucleus, we performed a yeast two-hybrid screening of the mouse fast skeletal muscle cDNA library and identified an interaction with troponin T3 (TnT3), which we subsequently confirmed by co-immunoprecipitation and co-localization assays in mouse skeletal muscle in vivo and in cultured C2C12 muscle cells. Interacting domains were mapped to the leucine zipper domain in TnT3 COOH-terminus (160-244 aa) and Cavβ1a NH2-terminus (1-99 aa), respectively. The double fluorescence assay in C2C12 cells co-expressing TnT3/DsRed and Cavβ1a/YFP shows that TnT3 facilitates Cavβ1a nuclear recruitment, suggesting that the two proteins play a heretofore unknown role during early muscle differentiation in addition to their classical role in ECC regulation.

  13. [Multiple perforation in cryogenically preserved bone allografts. Comparative histological and microradiographic study of perforated and non-perforated allograft in sheep].

    PubMed

    Simon, P; Babin, S R; Delloye, C; Schmitt, D

    1993-01-01

    Incorporation of massive cortical bone allografts in the human is slow and remains incomplete. Late biopsies of implanted allografts or histological studies of explanted allografts always show the partial substitution of necrotic bone by new bone from the host. The aim of the present study was to evaluate the value of drilling the massive deep-frozen cortical allografts in order to induce osteogenesis. Thirteen sheep were operated on and a standard segment of the proximal ulna was removed and the gap filled either by an unperforated allograft or by a perforated one. Based on histological and microradiographic examination, a complete substitution of the perforated allografts was observed but in this model no statistically significant difference was observed between perforated and unperforated allografts. Further study is needed to assess the effect of the perforations.

  14. c-Src/Cav1-dependent activation of the EGFR by Dsg2

    PubMed Central

    Roberts, Brett J.; Cooper, Felicia; Brennan-Crispi, Donna M.; Deguchi, Takahiro; Peltonen, Sirkku; James K., Wahl; Mahoney, M? G.

    2016-01-01

    The desmosomal cadherin, desmoglein 2 (Dsg2), is deregulated in a variety of human cancers including those of the skin. When ectopically expressed in the epidermis of transgenic mice, Dsg2 activates multiple mitogenic signaling pathways and increases susceptibility to tumorigenesis. However, the molecular mechanism responsible for Dsg2-mediated cellular signaling is poorly understood. Here we show overexpression as well as co-localization of Dsg2 and EGFR in cutaneous SCCs in vivo. Using HaCaT keratinocytes, knockdown of Dsg2 decreases EGFR expression and abrogates the activation of EGFR, c-Src and Stat3, but not Erk1/2 or Akt, in response to EGF ligand stimulation. To determine whether Dsg2 mediates signaling through lipid microdomains, sucrose density fractionation illustrated that Dsg2 is recruited to and displaces Cav1, EGFR and c-Src from light density lipid raft fractions. STED imaging confirmed that the presence of Dsg2 disperses Cav1 from the cell-cell borders. Perturbation of lipid rafts with the cholesterol-chelating agent MβCD also shifts Cav1, c-Src and EGFR out of the rafts and activates signaling pathways. Functionally, overexpression of Dsg2 in human SCC A431 cells enhances EGFR activation and increases cell proliferation and migration through a c-Src and EGFR dependent manner. In summary, our data suggest that Dsg2 stimulates cell growth and migration by positively regulating EGFR level and signaling through a c-Src and Cav1-dependent mechanism using lipid rafts as signal modulatory platforms. PMID:26918609

  15. Deletion of the L-type Calcium Channel CaV1.3 but not CaV1.2 Results in a Diminished sAHP in Mouse CA1 Pyramidal Neurons

    PubMed Central

    Gamelli, Amy E.; McKinney, Brandon C.; White, Jessica A.; Murphy, Geoffrey G.

    2009-01-01

    Trains of action potentials in CA1 pyramidal neurons are followed by a prolonged calcium-dependent post-burst afterhyperpolarization (AHP) that serves to limit further firing to a sustained depolarizing input. A reduction in the AHP accompanies acquisition of several types of learning and increases in the AHP are correlated with age-related cognitive impairment. The AHP develops primarily as the result of activation of outward calcium-activated potassium currents; however the precise source of calcium for activation of the AHP remains unclear. There is substantial experimental evidence suggesting that calcium influx via voltage-gated L-type calcium channels (L-VGCCs) contributes to the generation of the AHP. Two L-VGCC subtypes are predominately expressed in the hippocampus, CaV1.2 and CaV1.3, however it is not known which L-VGCC subtype is involved in generation of the AHP. This ambiguity is due in large part to the fact that at present there are no subunit-specific agonists or antagonists. Therefore, using mice in which the gene encoding CaV1.2 or CaV1.3 was deleted, we sought to determine the impact of alterations in levels of these two L-VCGG subtypes on neuronal excitability. No differences in any AHP measure were seen between neurons from CaV1.2 knockout mice and controls. However, the total area of the AHP was significantly smaller in neurons from CaV1.3 knockout mice as compared to neurons from wildtype controls. A significant reduction in the amplitude of the AHP was also seen at the 1 sec time point in neurons from CaV1.3 knockout mice as compared to those from controls. Reductions in both the area and 1 sec amplitude suggest the involvement of calcium influx via CaV1.3 in the slow AHP (sAHP). Thus, the results of our study demonstrate that deletion of CaV1.3, but not CaV1.2, significantly impacts the generation of the sAHP. PMID:20014384

  16. Quadriceps tendon allografts as an alternative to Achilles tendon allografts: a biomechanical comparison.

    PubMed

    Mabe, Isaac; Hunter, Shawn

    2014-12-01

    Quadriceps tendon with a patellar bone block may be a viable alternative to Achilles tendon for anterior cruciate ligament reconstruction (ACL-R) if it is, at a minimum, a biomechanically equivalent graft. The objective of this study was to directly compare the biomechanical properties of quadriceps tendon and Achilles tendon allografts. Quadriceps and Achilles tendon pairs from nine research-consented donors were tested. All specimens were processed to reduce bioburden and terminally sterilized by gamma irradiation. Specimens were subjected to a three phase uniaxial tension test performed in a custom environmental chamber to maintain the specimens at a physiologic temperature (37 ± 2 °C) and misted with a 0.9 % NaCl solution. There were no statistical differences in seven of eight structural and mechanical between the two tendon types. Quadriceps tendons exhibited a significantly higher displacement at maximum load and significantly lower stiffness than Achilles tendons. The results of this study indicated a biomechanical equivalence of aseptically processed, terminally sterilized quadriceps tendon grafts with bone block to Achilles tendon grafts with bone block. The significantly higher displacement at maximum load, and lower stiffness observed for quadriceps tendons may be related to the failure mode. Achilles tendons had a higher bone avulsion rate than quadriceps tendons (86 % compared to 12 %, respectively). This was likely due to observed differences in bone block density between the two tendon types. This research supports the use of quadriceps tendon allografts in lieu of Achilles tendon allografts for ACL-R.

  17. The surge of flavonoids as novel, fine regulators of cardiovascular Cav channels.

    PubMed

    Fusi, Fabio; Spiga, Ottavia; Trezza, Alfonso; Sgaragli, Giampietro; Saponara, Simona

    2017-02-05

    Ion channels underlie a wide variety of physiological processes that involve rapid changes in cell dynamics, such as cardiac and vascular smooth muscle contraction. Overexpression or dysfunction of these membrane proteins are the basis of many cardiovascular diseases that represent the leading cause of morbidity and mortality for human beings. In the last few years, flavonoids, widely distributed in the plant kingdom, have attracted the interest of many laboratories as an emerging class of fine ion, in particular Cav, channels modulators. Pieces of in vitro evidence for direct as well as indirect effects exerted by various flavonoids on ion channel currents are now accumulating in the scientific literature. This activity may be responsible, at least in part, for the beneficial and protective effects of dietary flavonoids toward cardiovascular diseases highlighted in several epidemiological studies. Here we examine numerous studies aimed at analysing this feature of flavonoids, focusing on the mechanisms that promote their sometimes controversial activities at cardiovascular Cav channels. New methodological approaches, such as molecular modelling and docking to Cav1.2 channel α1c subunit, used to elucidate flavonoids intrinsic mechanism of action, are introduced. Moreover, flavonoid-membrane interaction, bioavailability, and antioxidant activity are taken into account and discussed.

  18. Development of a Fresh Osteochondral Allograft Program Outside North America

    PubMed Central

    Tírico, Luís Eduardo Passarelli; Demange, Marco Kawamura; Santos, Luiz Augusto Ubirajara; de Rezende, Márcia Uchoa; Helito, Camilo Partezani; Gobbi, Riccardo Gomes; Pécora, José Ricardo; Croci, Alberto Tesconi; Bugbee, William Dick

    2015-01-01

    Objective To standardize and to develop a fresh osteochondral allograft protocol of procurement, processing and surgical utilization in Brazil. This study describes the steps recommended to make fresh osteochondral allografts a viable treatment option in a country without previous fresh allograft availability. Design The process involves regulatory process modification, developing and establishing procurement, and processing and surgical protocols. Results Legislation: Fresh osteochondral allografts were not feasible in Brazil until 2009 because the law prohibited preservation of fresh grafts at tissue banks. We approved an amendment that made it legal to preserve fresh grafts for 30 days from 2°C to 6°C in tissue banks. Procurement: We changed the protocol of procurement to decrease tissue contamination. All tissues were procured in an operating room. Processing: Processing of the grafts took place within 12 hours of tissue recovery. A serum-free culture media with antibiotics was developed to store the grafts. Surgeries: We have performed 8 fresh osteochondral allografts on 8 knees obtaining grafts from 5 donors. Mean preoperative International Knee Documentation Committee (IKDC) score was 31.99 ± 13.4, improving to 81.26 ± 14.7 at an average of 24 months’ follow-up. Preoperative Knee Injury and Oseoarthritis Outcome Score (KOOS) score was 46.8 ± 20.9 and rose to 85.24 ± 13.9 after 24 months. Mean preoperative Merle D’Aubigne-Postel score was 8.75 ± 2.25 rising to 16.1 ± 2.59 at 24 months’ follow-up. Conclusion To our knowledge, this is the first report of fresh osteochondral allograft transplantation in South America. We believe that this experience may be of value for physicians in countries that are trying to establish an osteochondral allograft transplant program. PMID:27375837

  19. Methenamine silver staining quantitative digital histochemistry in chronic allograft nephropathy.

    PubMed

    Sarioglu, S; Celik, A; Sakar, M; Sonmez, D; Tekis, D

    2004-12-01

    Renal function and final outcome of renal allografts have been correlated with irreversible damage. This study describes a quantitative histochemical method relying on periodic acid methenamine silver (PAMS) staining of all renal compartments. Among 60 renal allograft biopsies from 43 patients, 15 biopsies showing pure chronic allograft nephropathy were selected to determine PAMS-stained area percentage (SAP), using image analysis with quantitative histochemistry. Of the 15 cases, 9 (60%) were grade I and 6 (40%) were grade II chronic allograft nephropathy (CAN). The mean serum creatinine (sCr) value was 1.86 +/- 0.47 for allograft biopsies. The mean (+/-SD) SAP for the implantation biopsies was 10.58 +/- 1.87%, and for allograft biopsies 25.26 +/- 9.67 (P <.000). The serum creatinine (sCr) values for grade I versus II CAN were 1.63 +/- 0.24 versus 2.20 +/- 0.54 mg/dL, respectively (P=.019), and SAP values were 18.97 +/- 0.24 versus 34.7 +/- 5.89 (P=.003). There was a strong positive correlation between sCr values and SAP (P=.005; r=0.64). These findings show the PAMS approach to be a useful alternative method for reflecting damage in more than one compartment of the renal tissue. Also, the method can discriminated implantation and allograft biopsies as well as grade I and II CAN cases. The series is small for a multivariate analysis of the value of SAP measurements in PAMS-stained sections as a prognosticator, but the data support its use.

  20. Transmission of infection with human allografts: essential considerations in donor screening.

    PubMed

    Fishman, Jay A; Greenwald, Melissa A; Grossi, Paolo A

    2012-09-01

    Transmission of infection via transplantation of allografts including solid organs, eyes, and tissues are uncommon but potentially life-threatening events. Donor-derived infections have been documented following organ, tissue, and ocular transplants. Each year, more than 70 000 organs, 100 000 corneas, and 2 million human tissue allografts are implanted worldwide. Single donors may provide allografts for >100 organ and tissue recipients; each allograft carries some, largely unquantifiable, risk of disease transmission. Protocols for screening of organ or tissue donors for infectious risk are nonuniform, varying with the type of allograft, national standards, and availability of screening assays. In the absence of routine, active surveillance, coupled with the common failure to recognize or report transmission events, few data are available on the incidence of allograft-associated disease transmission. Research is needed to define the optimal screening assays and the transmissibility of infection with allografts. Approaches are reviewed that may contribute to safety in allograft transplantation.

  1. Genetic Tracing of Cav3.2 T-Type Calcium Channel Expression in the Peripheral Nervous System

    PubMed Central

    Bernal Sierra, Yinth A.; Haseleu, Julia; Kozlenkov, Alexey; Bégay, Valérie; Lewin, Gary R.

    2017-01-01

    Characterizing the distinct functions of the T-type ion channel subunits Cav3.1, 3.2 or 3.3 has proven difficult due to their highly conserved amino-acid sequences and the lack of pharmacological blockers specific for each subunit. To precisely determine the expression pattern of the Cav3.2 channel in the nervous system we generated two knock-in mouse strains that express EGFP or Cre recombinase under the control of the Cav3.2 gene promoter. We show that in the brains of these animals, the Cav3.2 channel is predominantly expressed in the dentate gyrus of the hippocampus. In the peripheral nervous system, the activation of the promoter starts at E9.5 in neural crest cells that will give rise to dorsal root ganglia (DRG) neurons, but not sympathetic neurons. As development progresses the number of DRG cells expressing the Cav3.2 channel reaches around 7% of the DRG at E16.5, and remains constant until E18.5. Characterization of sensory neuron subpopulations at E18.5 showed that EGFP+ cells are a heterogeneous population consisting mainly of TrkB+ and TrkC+ cells, while only a small percentage of DRG cells were TrkA+. Genetic tracing of the sensory nerve end-organ innervation of the skin showed that the activity of the Cav3.2 channel promoter in sensory progenitors marks many mechanoreceptor and nociceptor endings, but spares slowly adapting mechanoreceptors with endings associated with Merkel cells. Our genetic analysis reveals for the first time that progenitors that express the Cav3.2 T-type calcium channel, defines a sensory specific lineage that populates a large proportion of the DRG. Using our Cav3.2-Cre mice together with AAV viruses containing a conditional fluorescent reporter (tdTomato) we could also show that Cre expression is largely restricted to two functionally distinct sensory neuron types in the adult ganglia. Cav3.2 positive neurons innervating the skin were found to only form lanceolate endings on hair follicles and are probably identical to D

  2. Isoflurane, But Not the Nonimmobilizers F6 and F8, Inhibits Rat Spinal Cord Motor Neuron CaV1 Calcium Currents

    PubMed Central

    Recio-Pinto, Esperanza; Montoya-Gacharna, Jose V.; Xu, Fang; Blanck, Thomas J.J.

    2015-01-01

    Background Volatile anesthetics decrease Ca2+ entry through voltage-dependent Ca2+ channels. Ca2+ influences neurotransmitter release and neuronal excitability. Because volatile anesthetics act specifically on the spinal cord to produce immobility, we examined the effect of isoflurane and the nonimmobilizers F6 (1, 2- dichlorohexafluorocyclobutane) and F8 (2, 3- dichlorooctafluorobutane) on CaV1 and CaV2 Ca2+ channels in spinal cord motor neurons and dorsal root ganglion neurons. Methods Using patch clamping, we compared the effects of isoflurane with those of F6 and F8 on CaV1 and CaV2 channels in isolated, cultured adult rat spinal cord motor neurons and on CaV1 and CaV2 channels in adult rat dorsal root ganglion sensory neurons. Results In spinal cord motor neurons, isoflurane, but not F6 or F8, inhibited currents through CaV1 channels. Isoflurane and at least one of the nonimmobilizers inhibited currents through CaV1 and CaV2 channels in dorsal root ganglion neurons and Cav2 in spinal cord motor neurons Conclusion The findings that isoflurane, but not nonimmobilizers, inhibited CaV1 Ca2+ channels in spinal cord motor neurons are consistent with the notion that spinal cord motor neurons might mediate isoflurane-induced immobility. Additional studies are required to examine whether inhibition of CaV1 calcium currents in spinal cord motor neurons are sufficient, or whether actions on other channels/proteins also contribute to isoflurane-induced immobility. PMID:26702867

  3. The voltage-dependent L-type Ca2+ (CaV1.2) channel C-terminus fragment is a bi-modal vasodilator.

    PubMed

    Bannister, John P; Leo, Marie Dennis; Narayanan, Damodaran; Jangsangthong, Wanchana; Nair, Anitha; Evanson, Kirk W; Pachuau, Judith; Gabrick, Kyle S; Boop, Frederick A; Jaggar, Jonathan H

    2013-06-15

    Voltage-dependent L-type Ca(2+) channels (CaV1.2) are the primary Ca(2+) entry pathway in vascular smooth muscle cells (myocytes). CaV1.2 channels control systemic blood pressure and organ blood flow and are pathologically altered in vascular diseases, which modifies vessel contractility. The CaV1.2 distal C-terminus is susceptible to proteolytic cleavage, which yields a truncated CaV1.2 subunit and a cleaved C-terminal fragment (CCt). Previous studies in cardiac myocytes and neurons have identified CCt as both a transcription factor and CaV1.2 channel inhibitor, with different signalling mechanisms proposed to underlie some of these effects. CCt existence and physiological functions in arterial myocytes are unclear, but important to study given the functional significance of CaV1.2 channels. Here, we show that CCt exists in myocytes of both rat and human resistance-size cerebral arteries, where it locates to both the nucleus and plasma membrane. Recombinant CCt expression in arterial myocytes inhibited CaV1.2 transcription and reduced CaV1.2 protein. CCt induced a depolarizing shift in the voltage dependence of both CaV1.2 current activation and inactivation, and reduced non-inactivating current in myocytes. Recombinant truncated CCt lacking a putative nuclear localization sequence (92CCt) did not locate to the nucleus and had no effect on arterial CaV1.2 transcription or protein. However, 92CCt shifted the voltage dependence of CaV1.2 activation and inactivation similarly to CCt. CCt and 92CCt both inhibited pressure- and depolarization-induced vasoconstriction, although CCt was a far more effective vasodilator. These data demonstrate that endogenous CCt exists and reduces both CaV1.2 channel expression and voltage sensitivity in arterial myocytes. Thus, CCt is a bi-modal vasodilator.

  4. Arthroscopic posterior cruciate ligament reconstruction with allograft versus autograft

    PubMed Central

    Sun, Xiujiang; Zhang, Jianfeng; Qu, Xiaoyi

    2015-01-01

    Introduction The aim of the study was to compare and analyze retrospectively the outcomes of arthroscopic posterior cruciate ligament reconstruction with autograft versus allograft. Material and methods Seventy-one patients who underwent arthroscopic posterior cruciate ligament reconstruction with an autograft or allograft met our inclusion criteria. There were 36 patients in the autograft group and 35 patients in the allograft group. All the patients were evaluated by physical examination and a functional ligament test. Comparative analysis was done in terms of operation time, incision length, fever time, postoperative infection rate, incidence of numbness and dysesthesia around the incision, as well as a routine blood test. Results The average follow-up of the autograft group was 3.2 ±0.2 years and that of the allograft group was 3.3 ±0.6 years; there was no significant difference (p > 0.05). No differences existed in knee range of motion, Lysholm scores, International Knee Documentation Committee standard evaluation form and Tegner activity score at final follow-up (p > 0.05), except that patients in the allograft group had a shorter operation time and incision length and a longer fever time (p < 0.05). We found a difference in posterior drawer test and KT-2000 arthrometer assessment (p < 0.05). The posterior tibia displacement averaged 3.8 ±1.5 mm in the autograft group and 4.8 ±1.7 mm in the allograft group (p < 0.05). The incidence of numbness and dysesthesia around the incision in the autograft group was higher than that in the allograft group (p < 0.05). There was no infection postoperatively. The white blood cells and neutrophils in the allograft group increased more than those in the autograft group postoperatively (p < 0.05). Conclusions Both groups of patients had satisfactory outcomes after the operation. However, in the instrumented posterior laxity test, the autograft gave better results than the allograft. No differences in functional scores

  5. Voltage-dependent regulation of CaV2.2 channels by Gq-coupled receptor is facilitated by membrane-localized β subunit.

    PubMed

    Keum, Dongil; Baek, Christina; Kim, Dong-Il; Kweon, Hae-Jin; Suh, Byung-Chang

    2014-10-01

    G protein-coupled receptors (GPCRs) signal through molecular messengers, such as Gβγ, Ca(2+), and phosphatidylinositol 4,5-bisphosphate (PIP2), to modulate N-type voltage-gated Ca(2+) (CaV2.2) channels, playing a crucial role in regulating synaptic transmission. However, the cellular pathways through which GqPCRs inhibit CaV2.2 channel current are not completely understood. Here, we report that the location of CaV β subunits is key to determining the voltage dependence of CaV2.2 channel modulation by GqPCRs. Application of the muscarinic agonist oxotremorine-M to tsA-201 cells expressing M1 receptors, together with CaV N-type α1B, α2δ1, and membrane-localized β2a subunits, shifted the current-voltage relationship for CaV2.2 activation 5 mV to the right and slowed current activation. Muscarinic suppression of CaV2.2 activity was relieved by strong depolarizing prepulses. Moreover, when the C terminus of β-adrenergic receptor kinase (which binds Gβγ) was coexpressed with N-type channels, inhibition of CaV2.2 current after M1 receptor activation was markedly reduced and delayed, whereas the delay between PIP2 hydrolysis and inhibition of CaV2.2 current was decreased. When the Gβγ-insensitive CaV2.2 α1C-1B chimera was expressed, voltage-dependent inhibition of calcium current was virtually abolished, suggesting that M1 receptors act through Gβγ to inhibit CaV2.2 channels bearing membrane-localized CaV β2a subunits. Expression of cytosolic β subunits such as β2b and β3, as well as the palmitoylation-negative mutant β2a(C3,4S), reduced the voltage dependence of M1 muscarinic inhibition of CaV2.2 channels, whereas it increased inhibition mediated by PIP2 depletion. Together, our results indicate that, with membrane-localized CaV β subunits, CaV2.2 channels are subject to Gβγ-mediated voltage-dependent inhibition, whereas cytosol-localized β subunits confer more effective PIP2-mediated voltage-independent regulation. Thus, the voltage dependence of

  6. Significant prolongation of segmental pancreatic allograft survival in two species

    SciTech Connect

    Du Toit, D.F.; Heydenrych, J.J.

    1988-06-01

    A study was conducted to assess the suppression of segmental pancreatic allograft rejection by cyclosporine (CSA) alone in baboons and dogs, and subtotal marrow irradiation (TL1) alone and TL 1 in combination with CSA in baboons. Total pancreatectomy in the dog and primate provided a reliable diabetic model, induced an absolute deficiency of insulin and was uniformly lethal if not treated. Continuous administration of CSA in baboons resulted in modest allograft survival. As in baboons, dogs receiving CSA 25 mg/kg/d rendered moderate graft prolongation but a dose of 40 mg/kg/d resulted in significant graft survival (greater than 100 days) in 5 of 8 allograft recipients. Irradiation alone resulted in minimal baboon pancreatic allograft survival of 20 baboons receiving TL1 1,000 rad and CSA, 3 had graft survival greater than of 100 days. Of 15 baboons receiving TL1 800 rad and CSA, 6 had graft survival of greater than 100 days. In conclusion, CSA administration in dogs and TL1 in combination with CSA in baboons resulted in highly significant segmental pancreatic allograft survival.

  7. Imaging mouse lung allograft rejection with 1H MRI

    PubMed Central

    Guo, Jinbang; Huang, Howard J.; Wang, Xingan; Wang, Wei; Ellison, Henry; Thomen, Robert P.; Gelman, Andrew E.; Woods, Jason C.

    2014-01-01

    Purpose To demonstrate that longitudinal, non-invasive monitoring via MRI can characterize acute cellular rejection (ACR) in mouse orthotopic lung allografts. Methods Nineteen Balb/c donor to C57BL/6 recipient orthotopic left lung transplants were performed, further divided into control-Ig vs anti-CD4/anti-CD8 treated groups. A two-dimensional multi-slice gradient-echo pulse sequence synchronized with ventilation was used on a small-animal MR scanner to acquire proton images of lung at post-operative days 3, 7 and 14, just before sacrifice. Lung volume and parenchymal signal were measured, and lung compliance was calculated as volume change per pressure difference between high and low pressures. Results Normalized parenchymal signal in the control-Ig allograft increased over time, with statistical significance between day 14 and day 3 post transplantation (0.046→0.789, P < 0.05), despite large inter-mouse variations; this was consistent with histopathologic evidence of rejection. Compliance of the control-Ig allograft decreased significantly over time (0.013→0.003, P < 0.05), but remained constant in mice treated with anti-CD4/anti-CD8 antibodies. Conclusion Lung allograft rejection in individual mice can be monitored by lung parenchymal signal changes and by lung compliance through MRI. Longitudinal imaging can help us better understand the time course of individual lung allograft rejection and response to treatment. PMID:24954886

  8. T-cell alloimmunity and chronic allograft dysfunction.

    PubMed

    Safinia, Niloufar; Afzali, Behdad; Atalar, Kerem; Lombardi, Giovanna; Lechler, Robert I

    2010-12-01

    Solid organ transplantation is the standard treatment to improve both the quality of life and survival in patients with various end-stage organ diseases. The primary barrier against successful transplantation is recipient alloimmunity and the need to be maintained on immunosuppressive therapies with associated side effects. Despite such treatments in renal transplantation, after death with a functioning graft, chronic allograft dysfunction (CAD) is the most common cause of late allograft loss. Recipient recognition of donor histocompatibility antigens, via direct, indirect, and semidirect pathways, is critically dependent on the antigen-presenting cell (APC) and elicits effector responses dominated by recipient T cells. In allograft rejection, the engagement of recipient and donor cells results in recruitment of T-helper (Th) cells of the Th1 and Th17 lineage to the graft. In cases in which the alloresponse is dominated by regulatory T cells (Tregs), rejection can be prevented and the allograft tolerated with minimum or no immunosuppression. Here, we review the pathways of allorecognition that underlie CAD and the T-cell effector phenotypes elicited as part of the alloresponse. Future therapies including depletion of donor-reactive lymphocytes, costimulation blockade, negative vaccination using dendritic cell subtypes, and Treg therapy are inferred from an understanding of these mechanisms of allograft rejection.

  9. Allograft immune response with sCR1 intervention.

    PubMed

    Pratt, J R; Hibbs, M J; Laver, A J; Smith, R A; Sacks, S H

    1996-03-01

    The deposition of complement (C) components on tissues of transplanted organs may induce many proinflammatory responses. The role of such C activation in allograft rejection is uncertain. We addressed this question by inhibiting C at the level of the C3 and C5 convertases, preventing C activation and progression of its cascade, using recombinant human soluble complement receptor 1 (sCR1) in an unsensitized rat renal allograft model. Fully MHC disparate Lewis to DA rat renal allograft recipients given 25 mg/kg sCR1 daily, with saline-treated allograft recipients as controls (n = 15 in each group), were sacrificed from day 1 to day 5 post-transplant, and examined histopathologically, and for the deposition of C3 and C5b-9 membrane attack complex (MAC), and for the presence of leucocyte antigen markers. Treated animals demonstrated a reduction in vascular injury and cellular infiltration, coincident with reduced C deposition. Flow cytometric analysis of leucocyte subpopulations in the spleen showed a reduction in activated (CD25 positive) B and T cells in treated animals, compared to saline treated controls. The results suggest that C inhibition with sCR1, in an unsensitized model of allograft rejection, was able to suppress the vascular and cell mediated components of tissue injury. The data support not only a role for C in antibody and possibly cell mediated cytotoxicity in the graft, but also suggest a role in the primary immune response leading to both T cell and B cell activation.

  10. Differential gene expression pattern in biopsies with renal allograft pyelonephritis and allograft rejection

    PubMed Central

    Oghumu, Steve; Nori, Uday; Bracewell, Anna; Zhang, Jianying; Bott, Cherri; Nadasdy, Gyongyi M.; Brodsky, Sergey V.; Pelletier, Ronald; Satoskar, Abhay R.; Nadasdy, Tibor; Satoskar, Anjali A.

    2016-01-01

    Differentiating acute pyelonephritis (APN) from acute rejection (AR) in renal allograft biopsies can sometimes be difficult because of overlapping clinical and histologic features, lack of positive urine cultures, and variable response to antibiotics. We wanted to study differential gene expression between AR and APN using biopsy tissue. Thirty-three biopsies were analyzed using NanoString multiplex platform and PCR (6 transplant baseline biopsies, 8 AR, 15 APN [8 culture positive, 7 culture negative], and 4 native pyelonephritis [NP]). Additional 22 biopsies were tested by PCR to validate the results. CXCL9, CXCL10, CXCL11, and IDO1 were the top differentially expressed genes, upregulated in AR. Lactoferrin (LTF) and CXCL1 were higher in APN and NP. No statistically significant difference in transcript levels was seen between culture-positive and culture-negative APN biopsies. Comparing the overall mRNA signature using Ingenuity pathway analysis, interferon-gamma emerged as the dominant upstream regulator in AR and allograft APN, but not in NP (which clustered separately). Our study suggests that chemokine pathways in graft APN may differ from NP and in fact resemble AR, due to a component of alloreactivity, resulting in variable response to antibiotic treatment. Therefore, cautious addition of steroids might help in resistant cases of graft APN. PMID:27352120

  11. Allograft Reconstruction for the Treatment of Musculoskeletal Tumors of the Upper Extremity

    PubMed Central

    Aponte-Tinao, Luis A.; Ayerza, Miguel A.; Muscolo, D. Luis; Farfalli, German L.

    2013-01-01

    In comparison with the lower extremity, there is relatively paucity literature reporting survival and clinical results of allograft reconstructions after excision of a bone tumor of the upper extremity. We analyze the survival of allograft reconstructions in the upper extremity and analyze the final functional score according to anatomical site and type of reconstruction. A consecutive series of 70 allograft reconstruction in the upper limb with a mean followup of 5 years was analyzed, 38 osteoarticular allografts, 24 allograft-prosthetic composites, and 8 intercalary allografts. Kaplan-Meier survival analysis of the allografts was performed, with implant revision for any cause and amputation used as the end points. The function evaluation was performed using MSTS functional score. Sixteen patients (23%) had revision surgery for 5 factures, 2 infections, 5 allograft resorptions, and 2 local recurrences. Allograft survival at five years was 79% and 69% at ten years. In the group of patients treated with an osteoarticular allograft the articular surface survival was 90% at five years and 54% at ten years. The limb salvage rate was 98% at five and 10 years. We conclude that articular deterioration and fracture were the most frequent mode of failure in proximal humeral osteoarticular reconstructions and allograft resorption in elbow reconstructions. The best functional score was observed in the intercalary humeral allograft. PMID:23476115

  12. Inter-channel scaffolding of presynaptic CaV2.2 via the C terminal PDZ ligand domain.

    PubMed

    Gardezi, Sabiha R; Li, Qi; Stanley, Elise F

    2013-05-15

    Calcium entry through CaV2.2 calcium channels clustered at the active zone (AZ) of the presynaptic nerve terminal gates synaptic vesicle (SV) fusion and the discharge of neurotransmitters, but the mechanism of channel scaffolding remains poorly understood. Recent studies have implicated the binding of a PDZ ligand domain (PDZ-LD) at the tip of the channel C terminal to a partner PDZ domain on RIM1/2, a synaptic vesicle-associated protein. To explore CaV2.2 scaffolding, we created intracellular region fusion proteins and used these to test for binding by 'fishing' for native CaV2.2 channels from cell lysates. Fusion proteins mimicking the distal half of the channel C terminal (C3strep) reliably captured CaV2.2 from whole brain crude membrane or purified synaptosome membrane lysates, whereas channel I-II loop or the distal half of the II-III loop proteins were negative. This capture could be replicated in a non-synaptic environment using CaV2.2 expressed in a cell line. The distal tip PDZ-LD, DDWC-COOH, was confirmed as the critical binding site by block of pull-down with mimetic peptides. Pull-down experiments using brain crude membrane lysates confirmed that RIM1/2 can bind to the DDWC PDZ-LD. However, robust CaV2.2 capture was observed from synaptosome membrane or in the cell line expression system with little or no RIM1/2 co-capture. Thus, we conclude that CaV2.2 channels can scaffold to each other via an interaction that involves the PDZ-LD by an inter-channel linkage bridged by an unknown protein.

  13. Cefuroxime, rifampicin and pulse lavage in decontamination of allograft bone.

    PubMed

    Hirn, M; Laitinen, M; Pirkkalainen, S; Vuento, R

    2004-03-01

    The risk of bacterial infection through allogenic bone transplantation is one of the major problems facing tissue banks. Different screening methods and decontamination procedures are being used to achieve a safe surgical result. The purpose of this study was to investigate the contamination rate in fresh frozen bone allografts after treating them with different decontamination methods. The allografts were contaminated by rubbing on the operating theatre floor for 60 min, after which they were rinsed either with sterile physiological saline, cefuroxime or rifampicin solution or they were washed with low-pressure pulse lavage of sterile physiological saline. Our findings show that low-pressure pulse lavage with sterile saline solution is very effective in removing bacteria from bone allograft, when compared with the antibiotic solutions tested.

  14. Lung transplantation: chronic allograft dysfunction and establishing immune tolerance.

    PubMed

    Gracon, Adam S A; Wilkes, David S

    2014-08-01

    Despite significant medical advances since the advent of lung transplantation, improvements in long-term survival have been largely unrealized. Chronic lung allograft dysfunction, in particular obliterative bronchiolitis, is the primary limiting factor. The predominant etiology of obliterative bronchiolitis involves the recipient's innate and adaptive immune response to the transplanted allograft. Current therapeutic strategies have failed to provide a definitive treatment paradigm to improve long-term outcomes. Inducing immune tolerance is an emerging therapeutic strategy that abrogates allograft rejection, avoids immunosuppression, and improves long-term graft function. The aim of this review is to discuss the key immunologic components of obliterative bronchiolitis, describe the state of establishing immune tolerance in transplantation, and highlight those strategies being evaluated in lung transplantation.

  15. Cholera toxin-induced tolerance to allografts in mice.

    PubMed Central

    Tsuru, S; Taniguchi, M; Shinomiya, N; Fujisawa, H; Zinnaka, Y; Nomoto, K

    1987-01-01

    When C3H/HeN (C3H) mice were primed with viable C57BL/6 (B6) spleen cells and treated with cholera toxin (CT) on the same day, a profound tolerance to tumour allografts of B6 origin was induced. The tolerant state was sustained for as long as 6 weeks or more. Skin allografts of B6 were rejected by such tolerant C3H mice, although the survival times were prolonged very slightly. Generation of cytotoxic T lymphocytes was reduced markedly in the tolerant mice, whereas delayed footpad reaction to B6 cells was maintained at the normal immune level or higher. There is a possibility that a T-cell subset responsible for delayed footpad reaction is resistant to CT-induced tolerance and participates in the rejection of skin allografts in tolerant mice. PMID:2438209

  16. Mechanisms of stem subsidence in femoral impaction allografting.

    PubMed

    Albert, Carolyne; Frei, Hanspeter; Duncan, Clive; Fernlund, Goran

    2011-01-01

    Failure of the femoral component of total hip arthroplasty is often accompanied by bone loss that can pose a significant challenge to the orthopaedic surgeon. Femoral impaction allografting has attractive potential for restoring bone stock in deficient femurs. However, there have been reports of problematic postoperative stem subsidence with this procedure. Subsidence is highly variable among patients, and there is disagreement over the mechanisms that cause it. This article reviews the various mechanisms that can contribute to subsidence in femoral impaction allografting. Variables such as graft density, cement penetration profile, use of synthetic graft substitutes, or other graft additives are discussed, as well as their potential impact on subsidence. Finally, recommendations are made for future studies aiming to reduce the risk of excessive subsidence in femoral impaction allografting.

  17. Transcriptomic Profiling of Virus-Host Cell Interactions following Chicken Anaemia Virus (CAV) Infection in an In Vivo Model

    PubMed Central

    Giotis, Efstathios S.; Rothwell, Lisa; Scott, Alistair; Hu, Tuanjun; Talbot, Richard; Todd, Daniel; Burt, David W.; Glass, Elizabeth J.; Kaiser, Pete

    2015-01-01

    Chicken Anaemia Virus (CAV) is an economically important virus that targets lymphoid and erythroblastoid progenitor cells leading to immunosuppression. This study aimed to investigate the interplay between viral infection and the host’s immune response to better understand the pathways that lead to CAV-induced immunosuppression. To mimic vertical transmission of CAV in the absence of maternally-derived antibody, day-old chicks were infected and their responses measured at various time-points post-infection by qRT-PCR and gene expression microarrays. The kinetics of mRNA expression levels of signature cytokines of innate and adaptive immune responses were determined by qRT-PCR. The global gene expression profiles of mock-infected (control) and CAV-infected chickens at 14 dpi were also compared using a chicken immune-related 5K microarray. Although in the thymus there was evidence of induction of an innate immune response following CAV infection, this was limited in magnitude. There was little evidence of a Th1 adaptive immune response in any lymphoid tissue, as would normally be expected in response to viral infection. Most cytokines associated with Th1, Th2 or Treg subsets were down-regulated, except IL-2, IL-13, IL-10 and IFNγ, which were all up-regulated in thymus and bone marrow. From the microarray studies, genes that exhibited significant (greater than 1.5-fold, false discovery rate <0.05) changes in expression in thymus and bone marrow on CAV infection were mainly associated with T-cell receptor signalling, immune response, transcriptional regulation, intracellular signalling and regulation of apoptosis. Expression levels of a number of adaptor proteins, such as src-like adaptor protein (SLA), a negative regulator of T-cell receptor signalling and the transcription factor Special AT-rich Binding Protein 1 (SATB1), were significantly down-regulated by CAV infection, suggesting potential roles for these genes as regulators of viral infection or cell defence

  18. Autograft versus sterilized allograft for lateral calcaneal lengthening osteotomies

    PubMed Central

    Müller, Sebastian A.; Barg, Alexej; Vavken, Patrick; Valderrabano, Victor; Müller, Andreas M.

    2016-01-01

    Abstract Sterilized allografts may be less resistant to collapse and prone to nonunion leading to loss of correction in open wedge osteotomies. These adverse events usually occur at early time points (i.e., < 9 months postoperatively). The goal of this study was to compare sterilized allografts to autologous grafts in respect to secondary loss of hindfoot alignment and graft incorporation after lateral calcaneal lengthening osteotomies. Fifty patients (22 F/ 28 M, age: 16–69 years) who had undergone 50 lateral calcaneal lengthening osteotomies for adult flatfoot deformity were included in this retrospective study. Cortical sterilized allografts were used in 25 patients, autologous grafts in the remaining 25. Patients’ preoperative, 6 and 12 weeks, and 6 to 9 months follow-up weight-bearing radiographs of the affected foot were analyzed by 2 blinded radiologists: on each radiograph, graft incorporation, the talo-first metatarsal angle (TFMA), the talo-navicular coverage angle (TNCA), and the calcaneal pitch angle (CPA) were assessed. Loss of hindfoot alignment was defined as an increase of the TFMA or the TNCA or a decrease of the CPA, each by 5°. Inter- and intraclass correlation coefficients for TFMA, TNCA, and CPA measurements ranged from 0.93 to 0.99. At all follow-up visits, the ratio of patients with loss of hindfoot alignment and graft incorporation was not significantly different between the allograft and autograft group. However, loss of correction was associated with failure of graft incorporation. Compared with autografts, sterilized allografts do not increase the risk for loss of hindfoot alignment in lateral column lengthening of the calcaneus. With respect to mechanical resistance, allografts thus mean an equal and valid alternative without risk of donor site morbidities. PMID:27472719

  19. CaV3.2 calcium channels control NMDA receptor-mediated transmission: a new mechanism for absence epilepsy.

    PubMed

    Wang, Guangfu; Bochorishvili, Genrieta; Chen, Yucai; Salvati, Kathryn A; Zhang, Peng; Dubel, Steve J; Perez-Reyes, Edward; Snutch, Terrance P; Stornetta, Ruth L; Deisseroth, Karl; Erisir, Alev; Todorovic, Slobodan M; Luo, Jian-Hong; Kapur, Jaideep; Beenhakker, Mark P; Zhu, J Julius

    2015-07-15

    CaV3.2 T-type calcium channels, encoded by CACNA1H, are expressed throughout the brain, yet their general function remains unclear. We discovered that CaV3.2 channels control NMDA-sensitive glutamatergic receptor (NMDA-R)-mediated transmission and subsequent NMDA-R-dependent plasticity of AMPA-R-mediated transmission at rat central synapses. Interestingly, functional CaV3.2 channels primarily incorporate into synapses, replace existing CaV3.2 channels, and can induce local calcium influx to control NMDA transmission strength in an activity-dependent manner. Moreover, human childhood absence epilepsy (CAE)-linked hCaV3.2(C456S) mutant channels have a higher channel open probability, induce more calcium influx, and enhance glutamatergic transmission. Remarkably, cortical expression of hCaV3.2(C456S) channels in rats induces 2- to 4-Hz spike and wave discharges and absence-like epilepsy characteristic of CAE patients, which can be suppressed by AMPA-R and NMDA-R antagonists but not T-type calcium channel antagonists. These results reveal an unexpected role of CaV3.2 channels in regulating NMDA-R-mediated transmission and a novel epileptogenic mechanism for human CAE.

  20. Cav1.3 (CACNA1D) L‐type Ca2+ channel dysfunction in CNS disorders

    PubMed Central

    Striessnig, Jörg

    2016-01-01

    Abstract Cav1.3 belongs to the family of voltage‐gated L‐type Ca2+ channels and is encoded by the CACNA1D gene. Cav1.3 channels are not only essential for cardiac pacemaking, hearing and hormone secretion but are also expressed postsynaptically in neurons, where they shape neuronal firing and plasticity. Recent findings provide evidence that human mutations in the CACNA1D gene can confer risk for the development of neuropsychiatric disease and perhaps also epilepsy. Loss of Cav1.3 function, as shown in knock‐out mouse models and by human mutations, does not result in neuropsychiatric or neurological disease symptoms, whereas their acute selective pharmacological activation results in a depressive‐like behaviour in mice. Therefore it is likely that CACNA1D mutations enhancing activity may be disease relevant also in humans. Indeed, whole exome sequencing studies, originally prompted to identify mutations in primary aldosteronism, revealed de novo CACNA1D missense mutations permitting enhanced Ca2+ signalling through Cav1.3. Remarkably, apart from primary aldosteronism, heterozygous carriers of these mutations also showed seizures and neurological abnormalities. Different missense mutations with very similar gain‐of‐function properties were recently reported in patients with autism spectrum disorders (ASD). These data strongly suggest that CACNA1D mutations enhancing Cav1.3 activity confer a strong risk for – or even cause – CNS disorders, such as ASD. PMID:26842699

  1. CaV3.2 calcium channels control NMDA receptor-mediated transmission: a new mechanism for absence epilepsy

    PubMed Central

    Wang, Guangfu; Bochorishvili, Genrieta; Chen, Yucai; Salvati, Kathryn A.; Zhang, Peng; Dubel, Steve J.; Perez-Reyes, Edward; Snutch, Terrance P.; Stornetta, Ruth L.; Deisseroth, Karl; Erisir, Alev; Todorovic, Slobodan M.; Luo, Jian-Hong; Kapur, Jaideep; Beenhakker, Mark P.; Zhu, J. Julius

    2015-01-01

    CaV3.2 T-type calcium channels, encoded by CACNA1H, are expressed throughout the brain, yet their general function remains unclear. We discovered that CaV3.2 channels control NMDA-sensitive glutamatergic receptor (NMDA-R)-mediated transmission and subsequent NMDA-R-dependent plasticity of AMPA-R-mediated transmission at rat central synapses. Interestingly, functional CaV3.2 channels primarily incorporate into synapses, replace existing CaV3.2 channels, and can induce local calcium influx to control NMDA transmission strength in an activity-dependent manner. Moreover, human childhood absence epilepsy (CAE)-linked hCaV3.2(C456S) mutant channels have a higher channel open probability, induce more calcium influx, and enhance glutamatergic transmission. Remarkably, cortical expression of hCaV3.2(C456S) channels in rats induces 2- to 4-Hz spike and wave discharges and absence-like epilepsy characteristic of CAE patients, which can be suppressed by AMPA-R and NMDA-R antagonists but not T-type calcium channel antagonists. These results reveal an unexpected role of CaV3.2 channels in regulating NMDA-R-mediated transmission and a novel epileptogenic mechanism for human CAE. PMID:26220996

  2. Low-Voltage-Activated CaV3.1 Calcium Channels Shape T Helper Cell Cytokine Profiles.

    PubMed

    Wang, Huiyun; Zhang, Xuexin; Xue, Li; Xing, Juan; Jouvin, Marie-Hélène; Putney, James W; Anderson, Matthew P; Trebak, Mohamed; Kinet, Jean-Pierre

    2016-04-19

    Activation of T cells is mediated by the engagement of T cell receptors (TCRs) followed by calcium entry via store-operated calcium channels. Here we have shown an additional route for calcium entry into T cells-through the low-voltage-activated T-type CaV3.1 calcium channel. CaV3.1 mediated a substantial current at resting membrane potentials, and its deficiency had no effect on TCR-initiated calcium entry. Mice deficient for CaV3.1 were resistant to the induction of experimental autoimmune encephalomyelitis and had reduced productions of the granulocyte-macrophage colony-stimulating factor (GM-CSF) by central nervous system (CNS)-infiltrating T helper 1 (Th1) and Th17 cells. CaV3.1 deficiency led to decreased secretion of GM-CSF from in vitro polarized Th1 and Th17 cells. Nuclear translocation of the nuclear factor of activated T cell (NFAT) was also reduced in CaV3.1-deficient T cells. These data provide evidence for T-type channels in immune cells and their potential role in shaping the autoimmune response.

  3. Molecular and biophysical basis of glutamate and trace metal modulation of voltage-gated Cav2.3 calcium channels

    PubMed Central

    Vitko, Iuliia; Lazarenko, Roman M.; Orestes, Peihan; Todorovic, Slobodan M.

    2012-01-01

    Here, we describe a new mechanism by which glutamate (Glu) and trace metals reciprocally modulate activity of the Cav2.3 channel by profoundly shifting its voltage-dependent gating. We show that zinc and copper, at physiologically relevant concentrations, occupy an extracellular binding site on the surface of Cav2.3 and hold the threshold for activation of these channels in a depolarized voltage range. Abolishing this binding by chelation or the substitution of key amino acid residues in IS1–IS2 (H111) and IS2–IS3 (H179 and H183) loops potentiates Cav2.3 by shifting the voltage dependence of activation toward more negative membrane potentials. We demonstrate that copper regulates the voltage dependence of Cav2.3 by affecting gating charge movements. Thus, in the presence of copper, gating charges transition into the “ON” position slower, delaying activation and reducing the voltage sensitivity of the channel. Overall, our results suggest a new mechanism by which Glu and trace metals transiently modulate voltage-dependent gating of Cav2.3, potentially affecting synaptic transmission and plasticity in the brain. PMID:22371363

  4. Characterization of the substituted N-triazole oxindole TROX-1, a small-molecule, state-dependent inhibitor of Ca(V)2 calcium channels.

    PubMed

    Swensen, Andrew M; Herrington, James; Bugianesi, Randal M; Dai, Ge; Haedo, Rodolfo J; Ratliff, Kevin S; Smith, McHardy M; Warren, Vivien A; Arneric, Stephen P; Eduljee, Cyrus; Parker, David; Snutch, Terrance P; Hoyt, Scott B; London, Clare; Duffy, Joseph L; Kaczorowski, Gregory J; McManus, Owen B

    2012-03-01

    Biological, genetic, and clinical evidence provide validation for N-type calcium channels (Ca(V)2.2) as therapeutic targets for chronic pain. A state-dependent Ca(V)2.2 inhibitor may provide an improved therapeutic window over ziconotide, the peptidyl Ca(V)2.2 inhibitor used clinically. Supporting this notion, we recently reported that in preclinical models, the state-dependent Ca(V)2 inhibitor (3R)-5-(3-chloro-4-fluorophenyl)-3-methyl-3-(pyrimidin-5-ylmethyl)-1-(1H-1,2,4-triazol-3-yl)-1,3-dihydro-2H-indol-2-one (TROX-1) has an improved therapeutic window compared with ziconotide. Here we characterize TROX-1 inhibition of Cav2.2 channels in more detail. When channels are biased toward open/inactivated states by depolarizing the membrane potential under voltage-clamp electrophysiology, TROX-1 inhibits Ca(V)2.2 channels with an IC(50) of 0.11 μM. The voltage dependence of Ca(V)2.2 inhibition was examined using automated electrophysiology. TROX-1 IC(50) values were 4.2, 0.90, and 0.36 μM at -110, -90, and -70 mV, respectively. TROX-1 displayed use-dependent inhibition of Ca(V)2.2 with a 10-fold IC(50) separation between first (27 μM) and last (2.7 μM) pulses in a train. In a fluorescence-based calcium influx assay, TROX-1 inhibited Ca(V)2.2 channels with an IC(50) of 9.5 μM under hyperpolarized conditions and 0.69 μM under depolarized conditions. Finally, TROX-1 potency was examined across the Ca(V)2 subfamily. Depolarized IC(50) values were 0.29, 0.19, and 0.28 μM by manual electrophysiology using matched conditions and 1.8, 0.69, and 1.1 μM by calcium influx for Ca(V)2.1, Ca(V)2.2, and Ca(V)2.3, respectively. Together, these in vitro data support the idea that a state-dependent, non-subtype-selective Ca(V)2 channel inhibitor can achieve an improved therapeutic window over the relatively state-independent Ca(V)2.2-selective inhibitor ziconotide in preclinical models of chronic pain.

  5. Rare Presentations of Cytomegalovirus Infection in Renal Allograft Recipients

    PubMed Central

    Ardalan, Mohammadreza

    2012-01-01

    Cytomegalovirus is the most common viral infection after kidney transplantation. Clinical presentations of cytomegalovirus infection range from asymptomatic infection to organ-specific involvement. Most symptomatic infections manifest as fever and cytopenia. The gastrointestinal tract is the most common site of tissue-invasive infection, often presenting as diarrhea or gastrointestinal bleeding. Gastrointestinal obstruction, perforation, thrombosis of large gastrointestinal veins, splenic artery thrombosis, and pancreatitis are rare gastrointestinal presentations of cytomegalovirus infection. Renal-allograft ureteral stricture and skin involvement are other rare presentations of cytomegalovirus infection. hemophagocytic syndrome, thrombotic microangiopathy, adrenal insufficiency, and renal allograft artery stenosis are other rare symptoms of cytomegalovirus infection. PMID:23573461

  6. Successful liver allograft inflow reconstruction with the right gastroepiploic vein.

    PubMed

    Pinheiro, Rafael S; Cruz, Ruy J; Nacif, Lucas S; Vane, Matheus F; D'Albuquerque, Luiz A C

    2016-02-01

    Portal vein thrombosis is a common complication in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusual case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric orthotopic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advantage of avoiding the need of venous jump graft.

  7. Digital image analysis of bone allograft union in sheep.

    PubMed

    Bresler, F; Simon, P; Schmitt, D; Verhelpen, M; De Gasperi, M; Delloye, C

    1998-04-01

    We compared the reliability of computer-assisted radiographic analysis (CARA) and visual evaluation of radiographs to assess host-graft junctions. 68 host bone/allograft junctions were obtained from an ongoing study on bone allografting in sheep. At 6 months, the grafted tibias were explanted and healing of the host-graft junctions were macroscopically determined. 49 junctions were macroscopically healed, whereas 19 had not united. 51 (0.8) of the junctions were correctly classified by radiographs, while 63 (0.9) of the junctions were correctly classified by CARA (p = 0.03). These findings warrant further evaluation in a clinical setting.

  8. Adenosine triphosphate regulates the activity of guinea pig Cav1.2 channel by direct binding to the channel in a dose-dependent manner.

    PubMed

    Feng, Rui; Xu, Jianjun; Minobe, Etsuko; Kameyama, Asako; Yang, Lei; Yu, Lifeng; Hao, Liying; Kameyama, Masaki

    2014-05-01

    The present study is to investigate the mechanism by which ATP regulates Cav1.2 channel activity. Ventricular tissue was obtained from adult guinea pig hearts using collagenase. Ca(2+) channel activity was monitored using the patch-clamp technique. Proteins were purified using wheat germ agglutinin-Sepharose, and the concentration was determined using the Coomassie brilliant blue technique. ATP binding to the Cav1.2 channel was examined using the photoaffinity method. EDA-ATP-biotin maintains Ca(2+) channel activity in inside-out membrane patches. ATP directly bound to the Cav1.2 channel in a dose-dependent manner, and at least two molecules of ATP bound to one molecule of the Cav1.2 channel. Low levels of calmodulin (CaM) increased ATP binding to the Cav1.2 channel, but higher levels of CaM decreased ATP binding to the Cav1.2 channel. In addition, Ca(2+) was another regulator for ATP binding to the Cav1.2 channel. Furthermore, ATP bound to GST-fusion peptides of NH2-terminal region (amino acids 6-140) and proximal COOH-terminal region (amino acids 1,509-1,789) of the main subunit (α1C) of the Cav1.2 channel. Our data suggest that ATP might regulate Cav1.2 channel activity by directly binding to the Cav1.2 channel in a dose-dependent manner. In addition, the ATP-binding effect to the Cav1.2 channel was both CaM- and Ca(2+) dependent.

  9. Pharmacoresistant Cav 2·3 (E-type/R-type) voltage-gated calcium channels influence heart rate dynamics and may contribute to cardiac impulse conduction.

    PubMed

    Galetin, Thomas; Tevoufouet, Etienne E; Sandmeyer, Jakob; Matthes, Jan; Nguemo, Filomain; Hescheler, Jürgen; Weiergräber, Marco; Schneider, Toni

    2013-07-01

    Voltage-gated Ca(2+) channels regulate cardiac automaticity, rhythmicity and excitation-contraction coupling. Whereas L-type (Cav 1·2, Cav 1·3) and T-type (Cav 3·1, Cav 3·2) channels are widely accepted for their functional relevance in the heart, the role of Cav 2·3 Ca(2+) channels expressing R-type currents remains to be elucidated. We have investigated heart rate dynamics in control and Cav 2·3-deficient mice using implantable electrocardiogram radiotelemetry and pharmacological injection experiments. Autonomic block revealed that the intrinsic heart rate does not differ between both genotypes. Systemic administration of isoproterenol resulted in a significant reduction in interbeat interval in both genotypes. It remained unaffected after administering propranolol in Cav 2·3(-|-) mice. Heart rate from isolated hearts as well as atrioventricular conduction for both genotypes differed significantly. Additionally, we identified and analysed the developmental expression of two splice variants, i.e. Cav 2·3c and Cav 2·3e. Using patch clamp technology, R-type currents could be detected in isolated prenatal cardiomyocytes and be related to R-type Ca(2+) channels. Our results indicate that on the systemic level, the pharmacologically inducible heart rate range and heart rate reserve are impaired in Cav 2·3 (-|-) mice. In addition, experiments on Langendorff perfused hearts elucidate differences in basic properties between both genotypes. Thus, Cav 2·3 does not only contribute to the cardiac autonomous nervous system but also to intrinsic rhythm propagation.

  10. Porous allograft bone scaffolds: doping with strontium.

    PubMed

    Zhao, Yantao; Guo, Dagang; Hou, Shuxun; Zhong, Hongbin; Yan, Jun; Zhang, Chunli; Zhou, Ying

    2013-01-01

    Strontium (Sr) can promote the process of bone formation. To improve bioactivity, porous allograft bone scaffolds (ABS) were doped with Sr and the mechanical strength and bioactivity of the scaffolds were evaluated. Sr-doped ABS were prepared using the ion exchange method. The density and distribution of Sr in bone scaffolds were investigated by inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray spectroscopy (EDS). Controlled release of strontium ions was measured and mechanical strength was evaluated by a compressive strength test. The bioactivity of Sr-doped ABS was investigated by a simulated body fluid (SBF) assay, cytotoxicity testing, and an in vivo implantation experiment. The Sr molar concentration [Sr/(Sr+Ca)] in ABS surpassed 5% and Sr was distributed nearly evenly. XPS analyses suggest that Sr combined with oxygen and carbonate radicals. Released Sr ions were detected in the immersion solution at higher concentration than calcium ions until day 30. The compressive strength of the Sr-doped ABS did not change significantly. The bioactivity of Sr-doped material, as measured by the in vitro SBF immersion method, was superior to that of the Sr-free freeze-dried bone and the Sr-doped material did not show cytotoxicity compared with Sr-free culture medium. The rate of bone mineral deposition for Sr-doped ABS was faster than that of the control at 4 weeks (3.28 ± 0.23 µm/day vs. 2.60 ± 0.20 µm/day; p<0.05). Sr can be evenly doped into porous ABS at relevant concentrations to create highly active bone substitutes.

  11. Combined photodynamic therapy and ranibizumab for polypoidal choroidal vasculopathy: a 2-year result and systematic review

    PubMed Central

    Zhao, Meng; Zhou, Hai-Ying; Xu, Jun; Zhang, Feng; Wei, Wen-Bin; Liu, Ning-Pu

    2017-01-01

    AIM To report a cohort of patients with polypoidal choroidal vasculopathy (PCV) treated with photodynamic therapy (PDT) followed by intravitreal ranibizumab injection 24-48h later, and to compare the results between eyes with PCV treated by PDT followed by intravitreal anti-vascular endothelial growth factor (VEGF) injection and intravitreal anti-VEGF injection followed by PDT by Meta-analysis. METHODS Retrospective study and systematic literature review. Medical records of patients with PCV who were initially treated using PDT followed by intravitreal ranibizumab injection 24-48h after PDT and had completed at least 2y follow-up were reviewed and analyzed. Clinical data, including age, sex, best-corrected visual acuity (BCVA), fundus photograph, fluorescein angiography, indocyanine green angiography and optical coherence tomography were investigated. A systematic literature review was also conducted, and a visual outcome of studies over 1y was compared using Meta-analysis. RESULTS A total of 52 patients were included in the study. Mean BCVA at baseline and follow-up at 1 or 2y were 0.71±0.61, 0.51±0.36 and 0.68±0.51 logMAR, respectively. The cumulative hazard rate for recurrence at 1 and 2y follow-up was 15.4% and 30.3% respectively. The percentage of eyes with polyps regression at 3, 12 and 24mo follow-up was 88.5%, 84.6% and 67.3% respectively. A Meta-analysis based on 22 independent studies showed the overall vision improvements at 1, 2 and 3y follow-up were 0.13±0.04 (P<0.001), 0.12±0.03 (P<0.001), 0.16±0.06 (P<0.001), respectively. The proportion of polyps regression at 1y follow-up was 64.6% (95%CI: 51.5%, 77.7%, P<0.001) in 434 eyes treated by intravitreal anti-VEGF agents before PDT and 76.0% (95%CI: 64.8%, 87.3%, P=0.001) in 199 eyes treated by intravitreal anti-VEGF agents after PDT. CONCLUSION Intravitreal ranibizumab injection 24-48h following PDT effectively stabilizes visual acuity in the eye with PCV. PDT followed by intravitreal anti

  12. B Lymphocytes Differentially Influence Acute and Chronic Allograft Rejection in Mice1

    PubMed Central

    DiLillo, David J.; Griffiths, Robert; Seshan, Surya V.; Magro, Cynthia M.; Ruiz, Phillip; Coffman, Thomas M.; Tedder, Thomas F.

    2013-01-01

    The relative contributions of B lymphocytes and plasma cells during allograft rejection remain unclear. Therefore, the effects of B cell depletion on acute cardiac rejection, chronic renal rejection, and skin graft rejection were compared using CD20 or CD19 mAbs. Both CD20 and CD19 mAbs effectively depleted mature B cells, while CD19 mAb treatment depleted plasmablasts and some plasma cells. B cell depletion did not affect acute cardiac allograft rejection, although CD19 mAb treatment prevented allograft-specific IgG production. Strikingly, CD19 mAb treatment significantly reduced renal allograft rejection and abrogated allograft-specific IgG development, while CD20 mAb treatment did not. By contrast, B cell depletion exacerbated skin allograft rejection and augmented the proliferation of adoptively transferred alloantigen-specific CD4+ T cells, demonstrating that B cells can also negatively regulate allograft rejection. Thereby, B cells can either positively or negatively regulate allograft rejection depending on the nature of the allograft and the intensity of the rejection response. Moreover, CD19 mAb may represent a new approach for depleting both B cells and plasma cells to concomitantly impair T cell activation, inhibit the generation of new allograft-specific Abs, or reduce preexisting allograft-specific Ab levels in transplant patients. PMID:21248259

  13. Intraoperative culture positive allograft bone and subsequent postoperative infections: a retrospective review

    PubMed Central

    Sims, Laura; Kulyk, Paul; Woo, Allan

    2017-01-01

    Background Obtaining intraoperative cultures of allograft bone just before use in orthopedic procedures is standard practice in many centres; however, the association between positive cultures and subsequent surgical infections is unknown. Our study had 3 goals: to determine the prevalence of positive intraoperative allograft culture and subsequent infection; to determine if, in cases of subsequent infection, organisms isolated at reoperation were the same as those cultured from the allograft at the time of the index procedure; and to assess the costs associated with performing intraoperative allograft cultures. Methods In this retrospective case series, we obtained data on patients receiving allograft bone between 2009 and 2012. Patients receiving allograft with positive cultures were reviewed to identify cases of significant infection. Organisms isolated at reoperation were compared with the allograft culture taken at the time of implantation, and we performed a cost assessment. Results Of the 996 allograft bone grafts used, 43 (4.3%) had positive intraoperative cultures and significant postoperative infections developed in 2, requiring reoperation. Antibiotics based on culture results were prescribed in 24% of cases. Organisms cultured at the time of reoperation differed from those isolated initially. The cost of performing 996 allograft cultures was $169 320. Conclusion This series suggests that rates of positive intraoperative bone allograft culture are low, and subsequent infection is rare. In cases of postoperative infection, primary allograft culture and secondary tissue cultures isolated different organisms. Costs associated with performing cultures are high. Eliminating initial culture testing could save $42 500 per year in our health region. PMID:28234217

  14. [Elbow reconstruction with massive total osteoarticular allograft: early failure due to instability].

    PubMed

    Delloye, C; Cornu, O; Dubuc, J-E; Vincent, A; Barbier, O

    2004-06-01

    Total elbow allografts were implanted for the treatment of trauma-induced bone defects in three patients between 1986 and 1990. Six allografts were implanted and finally explanted. The longest follow-up for an implanted allograft was five years. Allografts had to be removed because of nonunion in one patient and gross instability in the others. A constrained elbow prosthesis was implanted in all three patients. This short series illustrates mid-term failure to be expected with total elbow allografts, mainly due to instability. Accordingly, we no longer recommend the use of total elbow allografts alone as a salvage procedure for bony defects. If an allograft is needed, it should be implanted with a prosthesis.

  15. CaV3.2 KO mice have altered retinal waves but normal direction selectivity.

    PubMed

    Hamby, Aaron M; Rosa, Juliana M; Hsu, Ching-Hsiu; Feller, Marla B

    2015-01-01

    Early in development, before the onset of vision, the retina establishes direction-selective responses. During this time period, the retina spontaneously generates bursts of action potentials that propagate across its extent. The precise spatial and temporal properties of these "retinal waves" have been implicated in the formation of retinal projections to the brain. However, their role in the development of direction selective circuits within the retina has not yet been determined. We addressed this issue by combining multielectrode array and cell-attached recordings to examine mice that lack the CaV3.2 subunit of T-type Ca2+ channels (CaV3.2 KO) because these mice exhibit disrupted waves during the period that direction selective circuits are established. We found that the spontaneous activity of these mice displays wave-associated bursts of action potentials that are altered from that of control mice: the frequency of these bursts is significantly decreased and the firing rate within each burst is reduced. Moreover, the projection patterns of the retina demonstrate decreased eye-specific segregation in the dorsal lateral geniculate nucleus (dLGN). However, after eye-opening, the direction selective responses of CaV3.2 KO direction selective ganglion cells (DSGCs) are indistinguishable from those of wild-type DSGCs. Our data indicate that although the temporal properties of the action potential bursts associated with retinal waves are important for activity-dependent refining of retinal projections to central targets, they are not critical for establishing direction selectivity in the retina.

  16. Salvileucalin B, a novel diterpenoid with an unprecedented rearranged neoclerodane skeleton from Salvia leucantha Cav.

    PubMed

    Aoyagi, Yutaka; Yamazaki, Akira; Nakatsugawa, Chihiro; Fukaya, Haruhiko; Takeya, Koichi; Kawauchi, Susumu; Izumi, Hiroshi

    2008-10-16

    Salvileucalin B (2), having an unprecedented rearranged neoclerodane skeleton, was isolated from the aerial parts of Salvia leucantha Cav. (Labiatae) along with salvileucalin A (1). The absolute structures were elucidated by spectroscopic analysis, X-ray crystallographic analysis, and vibrational circular dichroism. Compound 2 represents a novel neoclerodane, characterized by a tricyclo[3.2.1.0 (2,7)]octane substructure incorporating the exocyclic C-20 methylene of 1. This molecule exerted cytotoxic activity against A549 and HT-29 cells with IC50 values of 5.23 and 1.88 microg/mL, respectively.

  17. PIP₂ hydrolysis is responsible for voltage independent inhibition of CaV2.2 channels in sympathetic neurons.

    PubMed

    Vivas, Oscar; Castro, Hector; Arenas, Isabel; Elías-Viñas, David; García, David E

    2013-03-08

    GPCRs regulate Ca(V)2.2 channels through both voltage dependent and independent inhibition pathways. The aim of the present work was to assess the phosphatidylinositol-4,5-bisphosphate (PIP2) as the molecule underlying the voltage independent inhibition of Ca(V)2.2 channels in SCG neurons. We used a double pulse protocol to study the voltage independent inhibition and changed the PIP(2) concentration by means of blocking the enzyme PLC, filling the cell with a PIP(2) analogue and preventing the PIP(2) resynthesis with wortmannin. We found that voltage independent inhibition requires the activation of PLC and can be hampered by internal dialysis of exogenous PIP(2). In addition, the recovery from voltage independent inhibition is blocked by inhibition of the enzymes involved in the resynthesis of PIP(2). These results support that the hydrolysis of PIP(2) is responsible for the voltage independent inhibition of Ca(V)2.2 channels.

  18. G6PD deficiency and absence of α-thalassemia increase the risk for cerebral vasculopathy in children with sickle cell anemia.

    PubMed

    Joly, Philippe; Garnier, Nathalie; Kebaili, Kamila; Renoux, Céline; Dony, Arthur; Cheikh, Nathalie; Renard, Cécile; Ceraulo, Antony; Cuzzubbo, Daniela; Pondarré, Corinne; Martin, Cyril; Pialoux, Vincent; Francina, Alain; Bertrand, Yves; Connes, Philippe

    2016-04-01

    The aim of this study was to test the association between hematological/genetic factors and cerebral vasculopathy in children with sickle cell anemia (SCA). A group with cerebral vasculopathy (VASC) was composed of children who had stroke (n = 6), silent infarct (n = 11), or an abnormal transcranial Doppler (n = 5). Eighty-four patients had neither positive history of stroke or silent infarct, nor abnormal transcranial Doppler (NORM group). An intermediate group (COND; n = 15) was composed of SCA children with a conditional transcranial Doppler. Biological analyses were performed on samples obtained at steady state and before the beginning of any chronic treatment. The comparisons of the three groups demonstrated a protective effect of α-thalassemia against cerebral vasculopathy through its effects on hemoglobin and reticulocyte levels. Moreover, we observed higher frequency of G6PD deficiency in the VASC group compared with the other groups. Our study confirms the key role of α-thalassemia and G6PD status in the pathophysiology of cerebral vasculopathy in SCA children.

  19. Local complications of massive bone allografts: an appraisal of their prevalence in 128 patients.

    PubMed

    Delloye, Christian; van Cauter, Maïté; Dufrane, Denis; Francq, Bernard G; Docquier, Pierre-Louis; Cornu, Olivier

    2014-06-01

    Bone allografts were used in our department since twenty-five years to reconstruct segmental bone loss and our data were retrospectively reviewed to assess the complications related to the use of a bone allograft. A consecutive series of 128 patients who received a bone allograft was analyzed. The minimal follow-up was 18 months. Fracture, nonunion, infection and explantation were investigated using a multivariate analysis and logistical regression. Kaplan-Meier survival of the allograft was performed, using allograft removal as the end point. Tumour disease was excluded from this study. Patients were followed up for an average 103 months. Bone tumour occurred in 78% of the patients whereas revision arthroplasty was the cause of implantation in 15% of them. Nonunion was the most prevalent complication, occurring in 35% of the grafts. For nonunion occurrence, the type of reconstruction was found to be a significant variable, the intercalary allograft being the most exposed. Primary bone autografting at the anastomotic site was not significant to prevent nonunion. Fracture of the allograft was the second most frequent complication with a prevalence of 16.4%. The length of the allograft and an osteoarticular allograft were two significant variables in that occurrence. Infection of the allograft was present with a rate of 5.4% of patients. Explantation of failed allografts occurred in 30% of them. The duration of the frozen storage of the allograft and the donor age of the allograft were not significant on any local complication occurrence. Bone allografts are a reliable material but a high rate of local complications must be anticipated.

  20. Crystal structure of the CaV2 IQ domain in complex with Ca2+/calmodulin: high-resolution mechanistic implications for channel regulation by Ca2+.

    PubMed

    Mori, Masayuki X; Vander Kooi, Craig W; Leahy, Daniel J; Yue, David T

    2008-04-01

    Calmodulin (CaM) regulation of Ca(2+) channels is central to Ca(2+) signaling. Ca(V)1 versus Ca(V)2 classes of these channels exhibit divergent forms of regulation, potentially relating to customized CaM/IQ interactions among different channels. Here we report the crystal structures for the Ca(2+)/CaM IQ domains of both Ca(V)2.1 and Ca(V)2.3 channels. These highly similar structures emphasize that major CaM contacts with the IQ domain extend well upstream of traditional consensus residues. Surprisingly, upstream mutations strongly diminished Ca(V)2.1 regulation, whereas downstream perturbations had limited effects. Furthermore, our Ca(V)2 structures closely resemble published Ca(2+)/CaM-Ca(V)1.2 IQ structures, arguing against Ca(V)1/2 regulatory differences based solely on contrasting CaM/IQ conformations. Instead, alanine scanning of the Ca(V)2.1 IQ domain, combined with structure-based molecular simulation of corresponding CaM/IQ binding energy perturbations, suggests that the C lobe of CaM partially dislodges from the IQ element during channel regulation, allowing exposed IQ residues to trigger regulation via isoform-specific interactions with alternative channel regions.

  1. Critical role of CAV1/caveolin-1 in cell stress responses in human breast cancer cells via modulation of lysosomal function and autophagy.

    PubMed

    Shi, Yin; Tan, Shi-Hao; Ng, Shukie; Zhou, Jing; Yang, Na-Di; Koo, Gi-Bang; McMahon, Kerrie-Ann; Parton, Robert G; Hill, Michelle M; Del Pozo, Miguel A; Kim, You-Sun; Shen, Han-Ming

    2015-01-01

    CAV1 (caveolin 1, caveolae protein, 22kDa) is well known as a principal scaffolding protein of caveolae, a specialized plasma membrane structure. Relatively, the caveolae-independent function of CAV1 is less studied. Autophagy is a process known to involve various membrane structures, including autophagosomes, lysosomes, and autolysosomes for degradation of intracellular proteins and organelles. Currently, the function of CAV1 in autophagy remains largely elusive. In this study, we demonstrate for the first time that CAV1 deficiency promotes both basal and inducible autophagy. Interestingly, the promoting effect was found mainly in the late stage of autophagy via enhancing lysosomal function and autophagosome-lysosome fusion. Notably, the regulatory function of CAV1 in lysosome and autophagy was found to be caveolae-independent, and acts through lipid rafts. Furthermore, the elevated autophagy level induced by CAV1 deficiency serves as a cell survival mechanism under starvation. Importantly, downregulation of CAV1 and enhanced autophagy level were observed in human breast cancer cells and tissues. Taken together, our data reveal a novel function of CAV1 and lipid rafts in breast cancer development via modulation of lysosomal function and autophagy.

  2. A potent and selective indole N-type calcium channel (Ca(v)2.2) blocker for the treatment of pain.

    PubMed

    Tyagarajan, Sriram; Chakravarty, Prasun K; Park, Min; Zhou, Bishan; Herrington, James B; Ratliff, Kevin; Bugianesi, Randall M; Williams, Brande; Haedo, Rodolfo J; Swensen, Andrew M; Warren, Vivien A; Smith, McHardy; Garcia, Maria; Kaczorowski, Gregory J; McManus, Owen B; Lyons, Kathryn A; Li, Xiaohua; Madeira, Maria; Karanam, Bindhu; Green, Mitchell; Forrest, Michael J; Abbadie, Catherine; McGowan, Erin; Mistry, Shruti; Jochnowitz, Nina; Duffy, Joseph L

    2011-01-15

    N-type calcium channels (Ca(v)2.2) have been shown to play a critical role in pain. A series of low molecular weight 2-aryl indoles were identified as potent Ca(v)2.2 blockers with good in vitro and in vivo potency.

  3. Silencing of the Cav3.2 T-type calcium channel gene in sensory neurons demonstrates its major role in nociception

    PubMed Central

    Bourinet, Emmanuel; Alloui, Abdelkrim; Monteil, Arnaud; Barrère, Christian; Couette, Brigitte; Poirot, Olivier; Pages, Anne; McRory, John; Snutch, Terrance P; Eschalier, Alain; Nargeot, Joël

    2005-01-01

    Analgesic therapies are still limited and sometimes poorly effective, therefore finding new targets for the development of innovative drugs is urgently needed. In order to validate the potential utility of blocking T-type calcium channels to reduce nociception, we explored the effects of intrathecally administered oligodeoxynucleotide antisenses, specific to the recently identified T-type calcium channel family (CaV3.1, CaV3.2, and CaV3.3), on reactions to noxious stimuli in healthy and mononeuropathic rats. Our results demonstrate that the antisense targeting CaV3.2 induced a knockdown of the CaV3.2 mRNA and protein expression as well as a large reduction of ‘CaV3.2-like' T-type currents in nociceptive dorsal root ganglion neurons. Concomitantly, the antisense treatment resulted in major antinociceptive, anti-hyperalgesic, and anti-allodynic effects, suggesting that CaV3.2 plays a major pronociceptive role in acute and chronic pain states. Taken together, the results provide direct evidence linking CaV3.2 T-type channels to pain perception and suggest that CaV3.2 may offer a specific molecular target for the treatment of pain. PMID:15616581

  4. Apamin Boosting of Synaptic Potentials in CaV2.3 R-Type Ca2+ Channel Null Mice.

    PubMed

    Wang, Kang; Kelley, Melissa H; Wu, Wendy W; Adelman, John P; Maylie, James

    2015-01-01

    SK2- and KV4.2-containing K+ channels modulate evoked synaptic potentials in CA1 pyramidal neurons. Each is coupled to a distinct Ca2+ source that provides Ca2+-dependent feedback regulation to limit AMPA receptor (AMPAR)- and NMDA receptor (NMDAR)-mediated postsynaptic depolarization. SK2-containing channels are activated by Ca2+ entry through NMDARs, whereas KV4.2-containing channel availability is increased by Ca2+ entry through SNX-482 (SNX) sensitive CaV2.3 R-type Ca2+ channels. Recent studies have challenged the functional coupling between NMDARs and SK2-containing channels, suggesting that synaptic SK2-containing channels are instead activated by Ca2+ entry through R-type Ca2+ channels. Furthermore, SNX has been implicated to have off target affects, which would challenge the proposed coupling between R-type Ca2+ channels and KV4.2-containing K+ channels. To reconcile these conflicting results, we evaluated the effect of SK channel blocker apamin and R-type Ca2+ channel blocker SNX on evoked excitatory postsynaptic potentials (EPSPs) in CA1 pyramidal neurons from CaV2.3 null mice. The results show that in the absence of CaV2.3 channels, apamin application still boosted EPSPs. The boosting effect of CaV2.3 channel blockers on EPSPs observed in neurons from wild type mice was not observed in neurons from CaV2.3 null mice. These data are consistent with a model in which SK2-containing channels are functionally coupled to NMDARs and KV4.2-containing channels to CaV2.3 channels to provide negative feedback regulation of EPSPs in the spines of CA1 pyramidal neurons.

  5. Inhibition of the immune response to experimental fresh osteoarticular allografts

    SciTech Connect

    Rodrigo, J.J.; Schnaser, A.M.; Reynolds, H.M. Jr.; Biggart, J.M. 3d.; Leathers, M.W.; Chism, S.E.; Thorson, E.; Grotz, T.; Yang, Q.M. )

    1989-06-01

    The immune response to osteoarticular allografts is capable of destroying the cartilage--a tissue that has antigens on its cells identical to those on the bone and marrow cells. Osteoarticular allografts of the distal femur were performed in rats using various methods to attempt to temporarily inhibit the antibody response. The temporary systemic immunosuppressant regimens investigated were cyclophosphamide, azathioprine and prednisolone, cyclosporine A, and total lymphoid irradiation. The most successful appeared to be cyclosporine A, but significant side effects were observed. To specifically inhibit the immune response in the allograft antigens without systemically inhibiting the entire immune system, passive enhancement and preadministration of donor blood were tried. Neither was as effective as coating the donor bone with biodegradable cements, a method previously found to be successful. Cyclosporine A was investigated in dogs in a preliminary study of medial compartmental knee allografts and was found to be successful in inhibiting the antibody response and in producing a more successful graft; however, some significant side effects were similarly observed.

  6. Kidney allograft pyelonephritis caused by Salmonella enterica serovar Schwarzengrund.

    PubMed

    Ito, Kenta; Nishio, Haruomi; Iwatani, Yuji; Yamada, Ryo; Okawa, Takao; Yamamoto, Takumi; Murakami, Masaaki; Matsuo, Yoko; Matsuo, Ken; Tanaka, Satoshi; Mori, Kiyoshi; Mori, Noriko

    2017-03-13

    Kidney transplant recipients (KTRs) taking immunosuppressive drugs have a 20-fold greater risk of nontyphoidal Salmonella (NTS) infection than the healthy adult population. Among KTRs, the urinary tract is the most common site of infection. However, few cases of urinary tract infection caused by NTS have been documented in KTRs, and only one in Japan. Furthermore, it frequently induces acute allograft rejection with high mortality. Salmonella enterica subsp. enterica serovar Schwarzengrund (S. Schwarzengrund) is now among the more common Salmonella serovars isolated in Japan and is likely to be invasive. We present a case of a 45-year old female with vesicoureteral reflux to her transplanted kidney who developed kidney allograft pyelonephritis caused by S. Schwarzengrund. She was admitted to our hospital with fever, urodynia, lower abdominal pain, gross hematuria, and cloudy urine. Urine cultures were positive for S. Schwarzengrund. Exposure to cats, especially stray cats, were identified as the most likely source. We administered antibiotics for 4 weeks (ceftriaxone then amoxicillin, each for 2 weeks) and educated her about pet safety. She experienced no recurrence of infection or clinical kidney allograft rejection for 3 months post-treatment. NTS should be considered as a possible pathogen of urinary tract infection among KTRs, especially in cases with animal exposure or structural urologic abnormalities. When the pathogen is NTS, appropriate antibiotics and treatment periods are essential for preventing recurrence and allograft rejection after the completion of treatment.

  7. Recurrence of Acute Page Kidney in a Renal Transplant Allograft

    PubMed Central

    Zayas, Carlos; Mulloy, Laura; Jagadeesan, Muralidharan

    2016-01-01

    Acute Page Kidney (APK) phenomenon is a rare cause of secondary hypertension, mediated by activation of renin-angiotensin-aldosterone system (RAAS). Timely intervention is of great importance to prevent any end organ damage from hypertension. We present a unique case of three episodes of APK in the same renal transplant allograft. PMID:27725836

  8. Recurrence of Acute Page Kidney in a Renal Transplant Allograft.

    PubMed

    Kapoor, Rajan; Zayas, Carlos; Mulloy, Laura; Jagadeesan, Muralidharan

    2016-01-01

    Acute Page Kidney (APK) phenomenon is a rare cause of secondary hypertension, mediated by activation of renin-angiotensin-aldosterone system (RAAS). Timely intervention is of great importance to prevent any end organ damage from hypertension. We present a unique case of three episodes of APK in the same renal transplant allograft.

  9. Pulse lavage washing in decontamination of allografts improves safety.

    PubMed

    Hirn, M; Laitinen, M; Vuento, R

    2003-01-01

    We analyzed the bacterial contamination rate of 140 femoral head allografts after rinsing the allografts in different decontamination solutions. Bacterial screening methods and cleansing effect of antibiotics (cefuroxime and rifampicin) and pulse lavage were compared. Swabbing and taking small pieces of bone for culture were the screening methods used. Both methods proved to be quite unreliable. Approximately one-fourth of the results were false negative. Culturing small pieces of bone gave the most accurate and reliable results and, therefore, can be recommended as a bacterial screening method. The use of antibiotics in allograft decontamination is controversial. In prophylactic use antibiotics include risks of allergic reactions and resistant development and our results in the present study show that antibiotics do not improve the decontamination any better than low-pressure pulse lavage with sterile saline solution. Therefore, pulse lavage with sterile saline solution can be recommended for allograft decontamination. Our results demonstrate that it decreases bacterial bioburden as effectively as the antibiotics without persisting the disadvantages.

  10. Multifocal Primary Neoplasms in Kidney Allografts: Evaluation of Two Cases

    PubMed Central

    Ellis, Robert J.; Ng, Keng Lim; Samaratunga, Hemamali; Del Vecchio, Sharon J.; Wood, Simon T.

    2016-01-01

    Renal cell carcinoma (RCC) is the fifth most common malignancy in kidney transplant recipients, with increased risk arising due to immunosuppression. De novo RCC occurrence in kidney allografts is much less common when compared with the native kidneys. Multifocal RCC in allograft kidneys is rarely described. In this report, we discuss two cases of de novo multifocal renal neoplasms in allograft kidneys. Case 1 had three distinct neoplastic lesions of >5 mm, and case 2 had four. Using the World Health Organization 2016 classification of adult renal tumours, case 1 had one clear-cell (cc) RCC (grade 3) and two papillary adenomas; all confined to the kidney. Case 2 had a nodular lesion classified as ccRCC (grade 4) with focal rhabdoid differentiation and some infiltration of renal sinus fat; a cc tubulopapillary RCC; a multilocular cystic renal neoplasm of low malignant potential; and a mucinous tubular and spindle cell carcinoma; the last three all confined to the kidney. This is the first report of mucinous tubular and spindle cell carcinoma in a kidney allograft. When considering multifocal RCC with discordant histology, it is likely that these represent independent tumourigenic events. PMID:28326280

  11. Kidney allograft survival in dogs treated with total lymphoid irradiation

    SciTech Connect

    Howard, R.J.; Sutherland, D.E.R.; Lum, C.T.; Lewis, W.I.; Kim, T.H.; Slavin, S.; Najarian, J.S.

    1981-02-01

    Total lymphoid irradiation (TLI) is immunosuppressive and, in rodents, can induce a state where transplantation of allogenic bone marrow results in chimerism and permanent acceptance of organ allografts from the donor strain. Twelve splenectomized dogs were treated with TLI (150 rads per fraction, total dose 1950 to 3000 rads) before bilateral nephrectomy and renal allotransplantation. Eight dogs received bone marrow from the kidney donor. In 13 untreated control dogs renal allografts functioned for a mean +- (SE) of 4.7 +- 0.3 days. In the four TLI treated dogs who did not receive bone marrow the renal allografts functioned for 15 to 76 days (two dogs died with functioning grafts). In the eight TLI treated dogs who received donor bone marrow, two died immediately after transplantation, two rejected at 3 and 13 days, one died at 13 days with a functioning graft, and two have had the grafts function for longer than 500 days. Chimerism was not detected in the one dog tested. The response of peripheral blood lymphocytes to stimulation with phytohemaglutinin and in mixed lymphocyte culture was suppressed for at least one month after TLI. The results confirm the immunosuppressive effect of TLI. The absence of kidney rejection in two recipients of donor bone marrow show the potential of this approach to induce long-term immunologic unresponsiveness as to an organ allograft, but the outcome is unpredictable and further experiments are needed to define the optimal conditions for administration of TLI and bone marrow to the recipients.

  12. How to improve the incorporation of massive allografts?

    PubMed

    Delloye, C

    2003-01-01

    The incorporation of a bone graft is the result of creeping and substitutional activities that remove the original grafted bone and replace it by newly formed bone from the host cells. However, this intricate process is very limited in time and space. A bone allograft is poorly remodeled and is almost non viable even after several years of implantation. This lack of vitality accounts for the high rate of complications such as non union and fracture. One way to minimize the allograft complications is to improve its incorporation. The process of incorporation in animals and human beings is reviewed as well as the various avenues for a biologic improvement either through modulation on the host: the immune response, the inhibition of bone resorption, the use of bone morphogenetic proteins, the autogenous cell augmentation or through processing the bone allograft: bisphosphonate adsorption or bone perforations. In 2002, biologic enhancement of the incorporation is still in its infancy but will be in a near future a reality through influence on both the host and the allograft.

  13. Urine Proteomics to Detect Biomarkers for Chronic Allograft Dysfunction

    PubMed Central

    Quintana, Luís F.; Solé-Gonzalez, Amanda; Kalko, Susana G.; Bañon-Maneus, Elisenda; Solé, Manel; Diekmann, Fritz; Gutierrez-Dalmau, Alex; Abian, Joaquin; Campistol, Josep M.

    2009-01-01

    Despite optimal immunosuppressive therapy, more than 50% of kidney transplants fail because of chronic allograft dysfunction. A noninvasive means to diagnose chronic allograft dysfunction may allow earlier interventions that could improve graft half-life. In this proof-of-concept study, we used mass spectrometry to analyze differences in the urinary polypeptide patterns of 32 patients with chronic allograft dysfunction (14 with pure interstitial fibrosis and tubular atrophy and 18 with chronic active antibody-mediated rejection) and 18 control subjects (eight stable recipients and 10 healthy control subjects). Unsupervised hierarchical clustering showed good segregation of samples in groups corresponding mainly to the four biomedical conditions. Moreover, the composition of the proteome of the pure interstitial fibrosis and tubular atrophy group differed from that of the chronic active antibody-mediated rejection group, and an independent validation set confirmed these results. The 14 protein ions that best discriminated between these two groups correctly identified 100% of the patients with pure interstitial fibrosis and tubular atrophy and 100% of the patients with chronic active antibody-mediated rejection. In summary, this study establishes a pattern for two histologic lesions associated with distinct graft outcomes and constitutes a first step to designing a specific, noninvasive diagnostic tool for chronic allograft dysfunction. PMID:19056874

  14. Composite tissue allograft extends a helping hand to transplant immunologists.

    PubMed

    Thaunat, O; Badet, L; El-Jaafari, A; Kanitakis, J; Dubernard, J-M; Morelon, E

    2006-10-01

    The first successful human hand transplantation, performed on September 1998, has translated the scope of 'composite tissue allotransplantation' from research concepts into clinical practice. Beyond microsurgical problems that have been overcome several years ago, the main obstacle that still prevents the generalization of composite tissue allotransplantation is immunologic. This review, which summarizes the evidence obtained both from experimental animal models and from the first recipients of a hand transplant, is focused on the two immunological characteristics of composite allografts that set them apart from other solid organ allografts: (i) they contain skin tissue that elicits a strong immune response; and (ii) they contain lymphoid tissues (such as bone marrow and lymph nodes) that have the potential both to attack the recipient, and also to down-modulate the host immune response and induce tolerance. While on one hand, the composite tissue allografts raise new challenges to transplant immunologists, on the other they provide answers to questions that have remained unresolved for a long time. In this sense, composite tissue allografts extend a helping hand to transplant immunologists.

  15. Therapeutic lymphangiogenesis ameliorates established acute lung allograft rejection

    PubMed Central

    Cui, Ye; Liu, Kaifeng; Monzon-Medina, Maria E.; Padera, Robert F.; Wang, Hao; George, Gautam; Toprak, Demet; Abdelnour, Elie; D’Agostino, Emmanuel; Goldberg, Hilary J.; Perrella, Mark A.; Forteza, Rosanna Malbran; Rosas, Ivan O.; Visner, Gary; El-Chemaly, Souheil

    2015-01-01

    Lung transplantation is the only viable option for patients suffering from otherwise incurable end-stage pulmonary diseases such as chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis. Despite aggressive immunosuppression, acute rejection of the lung allograft occurs in over half of transplant recipients, and the factors that promote lung acceptance are poorly understood. The contribution of lymphatic vessels to transplant pathophysiology remains controversial, and data that directly address the exact roles of lymphatic vessels in lung allograft function and survival are limited. Here, we have shown that there is a marked decline in the density of lymphatic vessels, accompanied by accumulation of low-MW hyaluronan (HA) in mouse orthotopic allografts undergoing rejection. We found that stimulation of lymphangiogenesis with VEGF-C156S, a mutant form of VEGF-C with selective VEGFR-3 binding, alleviates an established rejection response and improves clearance of HA from the lung allograft. Longitudinal analysis of transbronchial biopsies from human lung transplant recipients demonstrated an association between resolution of acute lung rejection and decreased HA in the graft tissue. Taken together, these results indicate that lymphatic vessel formation after lung transplantation mediates HA drainage and suggest that treatments to stimulate lymphangiogenesis have promise for improving graft outcomes. PMID:26485284

  16. A Lifetime of Allograft Function with Kidneys from Older Donors.

    PubMed

    Rose, Caren; Schaeffner, Elke; Frei, Ulrich; Gill, Jagbir; Gill, John S

    2015-10-01

    Strategies to increase expanded criteria donor (ECD) transplantation are needed. We quantified the extent to which ECD kidneys provide recipients with a lifetime of allograft function by determining the difference between patient survival and death-censored allograft survival (graft survival). Initial analyses compared 5-year outcomes in the Eurotransplant Senior Program (European) and the United States Renal Data System. Among European recipients ≥65 years, patient survival exceeded graft survival, and ECD recipients returned to dialysis for an average of 5.2 months after transplant failure. Among United States recipients ≥60 years, graft survival exceeded patient survival. Although patient survival in elderly recipients in the United States was low (49% at 5 years), the average difference in patient survival at 10 years in elderly recipients in the United States with an ECD versus non-ECD transplant was only 7 months. The probability of patient survival with a functioning allograft at 5 years was higher with ECD transplantation within 1 year after activation to the waiting list than with delayed non-ECD transplantation ≥3 years after activation to the waiting list. Subsequent analyses demonstrated that ECD transplants do not provide a lifetime of allograft function in recipients <50 years in the United States. These findings should encourage ECD transplantation in patients ≥60 years, demonstrate that rapid ECD transplantation is superior to delayed non-ECD transplantation, and challenge the policy in the United States of allowing patients <50 years to receive an ECD transplant.

  17. Developmental expression of Ca(v)1.3 (alpha1d) calcium channels in the mouse inner ear.

    PubMed

    Hafidi, A; Dulon, D

    2004-06-21

    Voltage-gated calcium channels are important for neurotransmission at the level of inner hair cells (IHCs) and outer hair cells (OHCs). These channels open when mechanical stimulation depolarises the hair cell membrane and the resulting calcium influx triggers neurotransmitter release. Voltage-gated calcium channels expressed in hair cells are known to be of the L-type with a predominance of the Ca(v)1.3 subunit. The present study describes the developmental expression of the Ca(v)1.3 protein in the cochlea and the vestibular system using immunohistochemical technique. In the adult organ of Corti (OC), Ca(v)1.3 was localized in both sensory and non-sensory cells with a more intense expression in IHCs and Deiters cells when compared to OHCs. In both hair cell types, immunoreactivity was observed in the apical pole, basolateral membrane and at the basal pole (synaptic zone). Similar results were obtained in the vestibular organs. During development, Ca(v)1.3 immunoreactivity was observed in the cochlea as early as embryonic day 15, with expression increasing at birth. At these early stages of cochlear development, Ca(v)1.3 was expressed in all cell types surrounding the scala media. In the OC, the labeling was observed in IHCs, OHCs and supporting cells. The Ca(v)1.3 expression reached an adult-like pattern by the end of the second postnatal week. The present findings suggested that, in addition to their implication in hair cells synaptic transmission, Ca(v)1.3 calcium channels also play an important role in vesicle recycling and transport, as suggested by their extrasynaptic location at the apical pole of the hair cells. The Ca(v)1.3 channels in Deiters cells could participate in active calcium-induced changes in micromechanics of these supporting cells. An early expression during development suggested that these calcium channels are in addition important in the development of the cochlear and vestibular sensory epithelium.

  18. Altered thalamocortical rhythmicity and connectivity in mice lacking CaV3.1 T-type Ca2+ channels in unconsciousness

    PubMed Central

    Choi, Soonwook; Yu, Eunah; Lee, Seongwon; Llinás, Rodolfo R.

    2015-01-01

    In unconscious status (e.g., deep sleep and anesthetic unconsciousness) where cognitive functions are not generated there is still a significant level of brain activity present. Indeed, the electrophysiology of the unconscious brain is characterized by well-defined thalamocortical rhythmicity. Here we address the ionic basis for such thalamocortical rhythms during unconsciousness. In particular, we address the role of CaV3.1 T-type Ca2+ channels, which are richly expressed in thalamic neurons. Toward this aim, we examined the electrophysiological and behavioral phenotypes of mice lacking CaV3.1 channels (CaV3.1 knockout) during unconsciousness induced by ketamine or ethanol administration. Our findings indicate that CaV3.1 KO mice displayed attenuated low-frequency oscillations in thalamocortical loops, especially in the 1- to 4-Hz delta band, compared with control mice (CaV3.1 WT). Intriguingly, we also found that CaV3.1 KO mice exhibited augmented high-frequency oscillations during unconsciousness. In a behavioral measure of unconsciousness dynamics, CaV3.1 KO mice took longer to fall into the unconscious state than controls. In addition, such unconscious events had a shorter duration than those of control mice. The thalamocortical interaction level between mediodorsal thalamus and frontal cortex in CaV3.1 KO mice was significantly lower, especially for delta band oscillations, compared with that of CaV3.1 WT mice, during unconsciousness. These results suggest that the CaV3.1 channel is required for the generation of a given set of thalamocortical rhythms during unconsciousness. Further, that thalamocortical resonant neuronal activity supported by this channel is important for the control of vigilance states. PMID:26056284

  19. Cell-Free DNA and Active Rejection in Kidney Allografts.

    PubMed

    Bloom, Roy D; Bromberg, Jonathan S; Poggio, Emilio D; Bunnapradist, Suphamai; Langone, Anthony J; Sood, Puneet; Matas, Arthur J; Mehta, Shikha; Mannon, Roslyn B; Sharfuddin, Asif; Fischbach, Bernard; Narayanan, Mohanram; Jordan, Stanley C; Cohen, David; Weir, Matthew R; Hiller, David; Prasad, Preethi; Woodward, Robert N; Grskovic, Marica; Sninsky, John J; Yee, James P; Brennan, Daniel C

    2017-03-09

    Histologic analysis of the allograft biopsy specimen is the standard method used to differentiate rejection from other injury in kidney transplants. Donor-derived cell-free DNA (dd-cfDNA) is a noninvasive test of allograft injury that may enable more frequent, quantitative, and safer assessment of allograft rejection and injury status. To investigate this possibility, we prospectively collected blood specimens at scheduled intervals and at the time of clinically indicated biopsies. In 102 kidney recipients, we measured plasma levels of dd-cfDNA and correlated the levels with allograft rejection status ascertained by histology in 107 biopsy specimens. The dd-cfDNA level discriminated between biopsy specimens showing any rejection (T cell-mediated rejection or antibody-mediated rejection [ABMR]) and controls (no rejection histologically), P<0.001 (receiver operating characteristic area under the curve [AUC], 0.74; 95% confidence interval [95% CI], 0.61 to 0.86). Positive and negative predictive values for active rejection at a cutoff of 1.0% dd-cfDNA were 61% and 84%, respectively. The AUC for discriminating ABMR from samples without ABMR was 0.87 (95% CI, 0.75 to 0.97). Positive and negative predictive values for ABMR at a cutoff of 1.0% dd-cfDNA were 44% and 96%, respectively. Median dd-cfDNA was 2.9% (ABMR), 1.2% (T cell-mediated types ≥IB), 0.2% (T cell-mediated type IA), and 0.3% in controls (P=0.05 for T cell-mediated rejection types ≥IB versus controls). Thus, dd-cfDNA may be used to assess allograft rejection and injury; dd-cfDNA levels <1% reflect the absence of active rejection (T cell-mediated type ≥IB or ABMR) and levels >1% indicate a probability of active rejection.

  20. [The influence of HX- I on rabbit thyroid allografts].

    PubMed

    Wang, X; Shen, W; Tan, J; Du, C; Li, K; Huang, X

    1996-03-01

    We studied the anti-rejection effect of HX- I, a preparation of traditional Chinese herbs, on rabbit thyroid allografts. The transplantations were performed on 28 rabbits after total thyroidectomies. The grafting sites were in their pretrachial muscles. These animals were divided into four groups, namely, Group I: homografts: Group I: allografts without medication; Group II: allografts with dexamethason (0.25 mg/(kg.d) intramuscularly), and Group IV: allografts with HX-I water solution, (5g/(kg.d), peros). The medication lasted 28 days. Blood samples were drawn every week postoperatively. Serum T3 and T4 were tested by RIA. The grafts were removed for histopathological evaluation on the 28th day postoperatively. The histopathology of rejection and survival were scored and classified. On the 7th and 14th days, serum T3 and T4 levels were almost the same between groups. On the 21st and 28th days, the T3 and T4 levels were higher in Groups I and IV than those in Group II (P < 0.05). The histopathological findings were; in Group I, damaged follicles with much lymphocytes infiltration and fibrosis, and 6 cases being rejected; in Group II, two deaths and three cases with damaged thyroid tissue and much lymphocytes infiltration; in Group IV, three cases with damaged thyroid tissue and four intact grafts. Our results indicate that HX-I and dexamethason both can inhibit rejection in thyroid allografts in rabbits, but dexamethason has more side effects HX-I has many components and the machanism of its early anti-rejection effect is worthy of further study.

  1. Metabolomic Profiling in Individuals with a Failing Kidney Allograft

    PubMed Central

    Biancone, Luigi; Bussolino, Stefania; Merugumala, Sai; Tezza, Sara; D’Addio, Francesca; Ben Nasr, Moufida; Valderrama-Vasquez, Alessandro; Usuelli, Vera; De Zan, Valentina; El Essawy, Basset; Venturini, Massimo; Secchi, Antonio; De Cobelli, Francesco; Lin, Alexander; Chandraker, Anil; Fiorina, Paolo

    2017-01-01

    Background Alteration of certain metabolites may play a role in the pathophysiology of renal allograft disease. Methods To explore metabolomic abnormalities in individuals with a failing kidney allograft, we analyzed by liquid chromatography-mass spectrometry (LC-MS/MS; for ex vivo profiling of serum and urine) and two dimensional correlated spectroscopy (2D COSY; for in vivo study of the kidney graft) 40 subjects with varying degrees of chronic allograft dysfunction stratified by tertiles of glomerular filtration rate (GFR; T1, T2, T3). Ten healthy non-allograft individuals were chosen as controls. Results LC-MS/MS analysis revealed a dose-response association between GFR and serum concentration of tryptophan, glutamine, dimethylarginine isomers (asymmetric [A]DMA and symmetric [S]DMA) and short-chain acylcarnitines (C4 and C12), (test for trend: T1-T3 = p<0.05; p = 0.01; p<0.001; p = 0.01; p = 0.01; p<0.05, respectively). The same association was found between GFR and urinary levels of histidine, DOPA, dopamine, carnosine, SDMA and ADMA (test for trend: T1-T3 = p<0.05; p<0.01; p = 0.001; p<0.05; p = 0.001; p<0.001; p<0.01, respectively). In vivo 2D COSY of the kidney allograft revealed significant reduction in the parenchymal content of choline, creatine, taurine and threonine (all: p<0.05) in individuals with lower GFR levels. Conclusions We report an association between renal function and altered metabolomic profile in renal transplant individuals with different degrees of kidney graft function. PMID:28052095

  2. Regulation of Ca(V)2 calcium channels by G protein coupled receptors.

    PubMed

    Zamponi, Gerald W; Currie, Kevin P M

    2013-07-01

    Voltage gated calcium channels (Ca²⁺ channels) are key mediators of depolarization induced calcium influx into excitable cells, and thereby play pivotal roles in a wide array of physiological responses. This review focuses on the inhibition of Ca(V)2 (N- and P/Q-type) Ca²⁺-channels by G protein coupled receptors (GPCRs), which exerts important autocrine/paracrine control over synaptic transmission and neuroendocrine secretion. Voltage-dependent inhibition is the most widespread mechanism, and involves direct binding of the G protein βγ dimer (Gβγ) to the α1 subunit of Ca(V)2 channels. GPCRs can also recruit several other distinct mechanisms including phosphorylation, lipid signaling pathways, and channel trafficking that result in voltage-independent inhibition. Current knowledge of Gβγ-mediated inhibition is reviewed, including the molecular interactions involved, determinants of voltage-dependence, and crosstalk with other cell signaling pathways. A summary of recent developments in understanding the voltage-independent mechanisms prominent in sympathetic and sensory neurons is also included. This article is part of a Special Issue entitled: Calcium channels.

  3. Inaccuracy in selection of massive bone allograft using template comparison method.

    PubMed

    Paul, Laurent; Docquier, Pierre-Louis; Cartiaux, Olivier; Cornu, Olivier; Delloye, Christian; Banse, Xavier

    2008-06-01

    The use of massive bone allografts is increasing year by year and selection method remains unchanged. Superposition of patient's radiograph over allograft image and comparison of distances is the gold standard. Experiment was led to test selection procedure of a major european tissue bank. Four observers were asked to select an allograft for 10 fictive recipients. Nine allografts were provided. To simulate a perfect allograft, recipient himself was inserted in the pool of allografts (trap graft). The 10 potential bone transplants were classified in four categories (from adequate to unacceptable). In addition, observers were asked to choose the three best grafts for a given recipient. Quadratic kappa measuring agreement on classification between two observers ranged between 0.74 (substantial) and 0.47 (moderate). Trap graft was quoted by observers as adequate four times (10%) and was cited eight times (20%) among the three best matching allografts. None of the observers discovered that recipient was among allograft panel. This study demonstrates that current selection method is inaccurate for hemipelvic allograft selection. New methods should be developed and tested to assist tissue banks in bone allograft selection.

  4. Quantitative digital histochemistry with methenamine silver staining in renal allograft biopsies excluding pure chronic allograft nephropathy cases.

    PubMed

    Sarioglu, S; Sis, B; Celik, A; Tekis, D; Kavukcu, S; Bora, S; Camsari, T

    2006-03-01

    Deterioration of renal function is correlated with irreversible damage in chronic diseases. Recently we described a digital quantitative histochemistry method, relying on periodic acid methenamine silver (PAMS) staining to determine the chronic renal lesions. This index was strongly correlated with progressive deterioration of renal function in grafts with chronic allograft nephropathy (CAN). Herein the method has been applied to a cohort of renal allografts which were biopsied for various reasons, we sought to highlight its value to quantify chronic graft damage. Forty-four renal allograft biopsies from 37 patients with elevated serum creatinine values (SCr) underwent light microscopic image analysis (Mediscope, Dokuz Eylül University, Clinical Engineering Department, Izmir, Turkey) of the PAMS-stained area percentage (SAP). SCr was recorded at four intervals to overcome acute effects: the under SCr value before (SCr1) and after a biopsy within 3 months (SCr3), SCr at the time of the biopsy (SCr2), and the latest value (SCr4). The PAMS-SAP scores were strongly associated with increased interstitial fibrosis and tubular atrophy Banff scores (Kruskal-Wallis test, P = .006 and P = .003, respectively). There was a moderate positive correlation between PAMS and SCr3 (Pearson correlation test, P = .04, r = .312), and a strong positive correlation between time from transplantation to biopsy (Pearson correlation test, P < .000, r = .532). The present results show that PAMS-SAP seems to be of value to quantify renal scarring in allograft biopsies, reflecting four compartments. The strong correlation with time is noteworthy especially as a probable reflection of aging of the renal allograft.

  5. Whole Exome Sequencing Identifies De Novo Heterozygous CAV1 Mutations Associated with a Novel Neonatal Onset Lipodystrophy Syndrome

    PubMed Central

    Garg, Abhimanyu; Kircher, Martin; del Campo, Miguel; Amato, R. Stephen; Agarwal, Anil K.

    2016-01-01

    Despite remarkable progress in identifying causal genes for many types of genetic lipodystrophies in the last decade, the molecular basis of many extremely rare lipodystrophy patients with distinctive phenotypes remains unclear. We conducted whole exome sequencing of the parents and probands from six pedigrees with neonatal onset of generalized loss of subcutaneous fat with additional distinctive phenotypic features and report de novo heterozygous null mutations, c.424C>T (p. Q142*) and c.479_480delTT (p.F160*), in CAV1 in a 7-year-old male and a 3-year-old female of European origin, respectively. Both the patients had generalized fat loss, thin mottled skin and progeroid features at birth. The male patient had cataracts requiring extraction at age 30 months and the female patient had pulmonary arterial hypertension. Dermal fibroblasts of the female patient revealed negligible CAV1 immunofluorescence staining compared to control but there were no differences in the number and morphology of caveolae upon electron microscopy examination. Based upon the similarities in the clinical features of these two patients, previous reports of CAV1 mutations in patients with lipodystrophies and pulmonary hypertension, and similar features seen in CAV1 null mice, we conclude that these variants are the most likely cause of one subtype of neonatal onset generalized lipodystrophy syndrome. PMID:25898808

  6. Graded Ca2+/calmodulin-dependent coupling of voltage-gated CaV1.2 channels

    PubMed Central

    Dixon, Rose E; Moreno, Claudia M; Yuan, Can; Opitz-Araya, Ximena; Binder, Marc D; Navedo, Manuel F; Santana, Luis F

    2015-01-01

    In the heart, reliable activation of Ca2+ release from the sarcoplasmic reticulum during the plateau of the ventricular action potential requires synchronous opening of multiple CaV1.2 channels. Yet the mechanisms that coordinate this simultaneous opening during every heartbeat are unclear. Here, we demonstrate that CaV1.2 channels form clusters that undergo dynamic, reciprocal, allosteric interactions. This ‘functional coupling’ facilitates Ca2+ influx by increasing activation of adjoined channels and occurs through C-terminal-to-C-terminal interactions. These interactions are initiated by binding of incoming Ca2+ to calmodulin (CaM) and proceed through Ca2+/CaM binding to the CaV1.2 pre-IQ domain. Coupling fades as [Ca2+]i decreases, but persists longer than the current that evoked it, providing evidence for ‘molecular memory’. Our findings suggest a model for CaV1.2 channel gating and Ca2+-influx amplification that unifies diverse observations about Ca2+ signaling in the heart, and challenges the long-held view that voltage-gated channels open and close independently. DOI: http://dx.doi.org/10.7554/eLife.05608.001 PMID:25714924

  7. Adiponectin at Physiologically Relevant Concentrations Enhances the Vasorelaxative Effect of Acetylcholine via Cav-1/AdipoR-1 Signaling

    PubMed Central

    Du, Yunhui; Li, Rui; Lau, Wayne Bigond; Zhao, Jianli; Lopez, Bernard; Christopher, Theodore A.; Ma, Xin-Liang; Wang, Yajing

    2016-01-01

    Clinical studies have identified hypoadiponectinemia as an independent hypertension risk factor. It is known that adiponectin (APN) can directly cause vasodilation, but the doses required exceed physiologic levels several fold. In the current study, we determine the effect of physiologically relevant APN concentrations upon vascular tone, and investigate the mechanism(s) responsible. Physiologic APN concentrations alone induced no significant vasorelaxation. Interestingly, pretreatment of wild type mouse aortae with physiologic APN levels significantly enhanced acetylcholine (ACh)-induced vasorelaxation (P<0.01), an endothelium-dependent and nitric oxide (NO)-mediated process. Knockout of adiponectin receptor 1 (AdipoR1) or caveolin-1 (Cav-1, a cell signaling facilitating molecule), but not adiponectin receptor 2 (AdipoR2) abolished APN-enhanced ACh-induced vasorelaxation. Immunoblot assay revealed APN promoted the AdipoR1/Cav1 signaling complex in human endothelial cells. Treatment of HUVECs with physiologic APN concentrations caused significant eNOS phosphorylation and nitric oxide (NO) production (P<0.01), an effect abolished in knockdown of either AdipoR1 or Cav-1. Taken together, these data demonstrate for the first time physiologic APN levels enhance the vasorelaxative response to ACh by inducing NO production through AdipoR1/Cav-1 mediated signaling. In physiologic conditions, APN plays an important function of maintaining vascular tone. PMID:27023866

  8. Large Ca2+-dependent facilitation of CaV2.1 channels revealed by Ca2+ photo-uncaging

    PubMed Central

    Lee, Shin-Rong; Adams, Paul J; Yue, David T

    2015-01-01

    Key points CaV2.1 channels constitute a dominant Ca2+ entry pathway into brain neurons, triggering downstream Ca2+-dependent processes such as neurotransmitter release. CaV2.1 is itself modulated by Ca2+, resulting in activity-dependent enhancement of channel opening termed Ca2+-dependent facilitation (CDF). Real-time Ca2+ imaging and Ca2+ uncaging here reveal that CDF turns out to be strikingly faster, more Ca2+ sensitive, and larger than anticipated on previous grounds. Robust resolution of the quantitative profile of CDF enables deduction of a realistic biophysical model for this process. These results suggest that CaV2.1 CDF would figure most prominently in short-term synaptic plasticity and cerebellar Purkinje cell rhythmicity. Abstract CaV2.1 (P-type) voltage-gated Ca2+ channels constitute a major source of neuronal Ca2+ current, strongly influencing rhythmicity and triggering neurotransmitter release throughout the central nervous system. Fitting with such stature among Ca2+ entry pathways, CaV2.1 is itself feedback regulated by intracellular Ca2+, acting through calmodulin to facilitate channel opening. The precise neurophysiological role of this calcium-dependent facilitation (CDF) remains uncertain, however, in large measure because the very magnitude, Ca2+ dependence and kinetics of CDF have resisted quantification by conventional means. Here, we utilize the photo-uncaging of Ca2+ with CaV2.1 channels fluxing Li+ currents, so that voltage-dependent activation of channel gating is no longer conflated with Ca2+ entry, and CDF is then driven solely by light-induced increases in Ca2+. By using this strategy, we now find that CDF can be unexpectedly large, enhancing currents by as much as twofold at physiological voltages. CDF is steeply Ca2+ dependent, with a Hill coefficient of approximately two, a half-maximal effect reached by nearly 500 nm Ca2+, and Ca2+ on/off kinetics in the order of milliseconds to tens of milliseconds. These properties were

  9. Association of eNOS and Cav-1 gene polymorphisms with susceptibility risk of large artery atherosclerotic stroke

    PubMed Central

    Shyu, Hann-Yeh; Chen, Ming-Hua; Hsieh, Yi-Hsien; Shieh, Jia-Ching; Yen, Ling-Rong; Wang, Hsiao-Wei; Cheng, Chun-Wen

    2017-01-01

    Endothelial nitric oxide synthase (eNOS) is localized in caveole and has important effects on caveolar coordination through its interaction with caveolin-1 (Cav-1), which supports normal functioning of vascular endothelial cells. However, the relationship between genotypic polymorphisms of e-NOS and Cav-1 genes and ischemic stroke (IS) remains lesser reported. This hospital-based case-control study aimed to determine the genetic polymorphisms of the eNOS (Glu298Asp) and Cav-1 (G14713A and T29107A) genes in association with susceptibility risk in patients who had suffered from a large artery atherosclerotic (LAA) stroke. Genotyping determination for these variant alleles was performed using the TaqMan assay. The distributions of observed allelic and genotypic frequencies for the polymorphisms were in Hardy-Weinberg equilibrium in healthy controls. The risk for an LAA stroke in the Asp298 variant was 1.72 (95% CI = 1.09–2.75) versus Glu298 of the eNOS. In the GA/AA (rs3807987) variant, it was 1.79 (95% CI = 1.16–2.74) versus GG and in TA/AA (rs7804372) was 1.61 (95% CI = 1.06–2.43) versus TT of the Cav-1, respectively. A tendency toward an increased LAA stroke risk was significant in carriers with the eNOS Glu298Asp variant in conjunction with the G14713 A and T29107A polymorphisms of the Cav-1 (aOR = 2.03, P-trend = 0.002). A synergistic effect between eNOS and Cav-1 polymorphisms on IS risk elevation was significantly influenced by alcohol drinking, heavy cigarette smoking (P-trend<0.01), and hypercholesterolemia (P-trend < 0.001). In conclusion, genotypic polymorphisms of the eNOS Glu298Asp and Cav-1 14713A/29107A polymorphisms are associated with the elevated risk of LAA stroke among Han Chinese in Taiwan. PMID:28346478

  10. The use of deep frozen and irradiated bone allografts in the reconstruction of tibial plateau fractures.

    PubMed

    Feng, Wei; Fu, Li; Liu, Jianguo; Li, Dongsong; Qi, Xin

    2013-09-01

    To investigate the clinical behavior of deep frozen and irradiated bone allografts in the treatment of depressed tibial plateau fractures. Twenty-two patients with a tibial plateau fracture were treated with cancellous bone allografts. The bone allograft preparation process included fresh-freezing at -70 °C for 4 weeks and gamma-irradiation at 25 kGy. All of the patients were followed for 1-2 years. The clinical effects were assessed using the Rasmussen score for tibial head fractures and X-rays. Postoperatively, the average excellent and fair Rasmussen scores were 88.9%. Only one patient developed an infection, with no integration between allograft and recipient bone observed. All of the other bone allografts were incorporated successfully, and no osteoporosis or sclerosis was observed. The frozen and gamma-irradiated bone allograft is a good alternative in the treatment of tibial plateau fractures, which we have shown can integrate with the surrounding host bone.

  11. Micro-organisms isolated from cadaveric samples of allograft musculoskeletal tissue.

    PubMed

    Varettas, Kerry

    2013-12-01

    Allograft musculoskeletal tissue is commonly used in orthopaedic surgical procedures. Cadaveric donors of musculoskeletal tissue supply multiple allografts such as tendons, ligaments and bone. The microbiology laboratory of the South Eastern Area Laboratory Services (SEALS, Australia) has cultured cadaveric allograft musculoskeletal tissue samples for bacterial and fungal isolates since 2006. This study will retrospectively review the micro-organisms isolated over a 6-year period, 2006-2011. Swab and tissue samples were received for bioburden testing and were inoculated onto agar and/or broth culture media. Growth was obtained from 25.1 % of cadaveric allograft musculoskeletal tissue samples received. The predominant organisms isolated were coagulase-negative staphylococci and coliforms, with the heaviest bioburden recovered from the hemipelvis. The rate of bacterial and fungal isolates from cadaveric allograft musculoskeletal tissue samples is higher than that from living donors. The type of organism isolated may influence the suitability of the allograft for transplant.

  12. Kidney retransplantation for BK virus nephropathy with active viremia without allograft nephrectomy.

    PubMed

    Huang, Jingbo; Danovitch, Gabriel; Pham, Phuong-Thu; Bunnapradist, Suphamai; Huang, Edmund

    2015-12-01

    BK virus nephropathy is an important cause of kidney allograft failure. Retransplantation has been successfully performed for patients with previous allograft loss due to BK virus nephropathy; however, whether allograft nephrectomy and viral clearance are required prior to retransplantation is controversial. Some recent studies have suggested that retransplantion can be successfully achieved without allograft nephrectomy if viremia is cleared prior to retransplant. The only published experience of successful retransplantation in the presence of active viremia occurred in the presence of concomitant allograft nephrectomy of the failing kidney. In this report, we describe a case of successful repeat kidney transplant in a patient with high-grade BK viremia and fulminant hepatic failure without concomitant allograft nephrectomy performed under the setting of a simultaneous liver-kidney transplant.

  13. Lipidomics comparing DCD and DBD liver allografts uncovers lysophospholipids elevated in recipients undergoing early allograft dysfunction.

    PubMed

    Xu, Jin; Casas-Ferreira, Ana M; Ma, Yun; Sen, Arundhuti; Kim, Min; Proitsi, Petroula; Shkodra, Maltina; Tena, Maria; Srinivasan, Parthi; Heaton, Nigel; Jassem, Wayel; Legido-Quigley, Cristina

    2015-12-04

    Finding specific biomarkers of liver damage in clinical evaluations could increase the pool of available organs for transplantation. Lipids are key regulators in cell necrosis and hence this study hypothesised that lipid levels could be altered in organs suffering severe ischemia. Matched pre- and post-transplant biopsies from donation after circulatory death (DCD, n = 36, mean warm ischemia time = 2 min) and donation after brain death (DBD, n = 76, warm ischemia time = none) were collected. Lipidomic discovery and multivariate analysis (MVA) were applied. Afterwards, univariate analysis and clinical associations were conducted for selected lipids differentiating between these two groups. MVA grouped DCD vs. DBD (p = 6.20 × 10(-12)) and 12 phospholipids were selected for intact lipid measurements. Two lysophosphatidylcholines, LysoPC (16:0) and LysoPC (18:0), showed higher levels in DCD at pre-transplantation (q < 0.01). Lysophosphatidylcholines were associated with aspartate aminotransferase (AST) 14-day post-transplantation (q < 0.05) and were more abundant in recipients undergoing early allograft dysfunction (EAD) (p < 0.05). A receiver-operating characteristics (ROC) curve combining both lipid levels predicted EAD with 82% accuracy. These findings suggest that LysoPC (16:0) and LysoPC (18:0) might have a role in signalling liver tissue damage due to warm ischemia before transplantation.

  14. Transcriptional Response of Human Neurospheres to Helper-Dependent CAV-2 Vectors Involves the Modulation of DNA Damage Response, Microtubule and Centromere Gene Groups

    PubMed Central

    Licursi, Valerio; Brito, Catarina; La Torre, Mattia; Alves, Paula M.; Simao, Daniel; Mottini, Carla; Salinas, Sara; Negri, Rodolfo; Tagliafico, Enrico; Kremer, Eric J.; Saggio, Isabella

    2015-01-01

    Brain gene transfer using viral vectors will likely become a therapeutic option for several disorders. Helper-dependent (HD) canine adenovirus type 2 vectors (CAV-2) are well suited for this goal. These vectors are poorly immunogenic, efficiently transduce neurons, are retrogradely transported to afferent structures in the brain and lead to long-term transgene expression. CAV-2 vectors are being exploited to unravel behavior, cognition, neural networks, axonal transport and therapy for orphan diseases. With the goal of better understanding and characterizing HD-CAV-2 for brain therapy, we analyzed the transcriptomic modulation induced by HD-CAV-2 in human differentiated neurospheres derived from midbrain progenitors. This 3D model system mimics several aspects of the dynamic nature of human brain. We found that differentiated neurospheres are readily transduced by HD-CAV-2 and that transduction generates two main transcriptional responses: a DNA damage response and alteration of centromeric and microtubule probes. Future investigations on the biochemistry of processes highlighted by probe modulations will help defining the implication of HD-CAV-2 and CAR receptor binding in enchaining these functional pathways. We suggest here that the modulation of DNA damage genes is related to viral DNA, while the alteration of centromeric and microtubule probes is possibly enchained by the interaction of the HD-CAV-2 fibre with CAR. PMID:26207738

  15. Cav3.2 T-type calcium channel is required for the NFAT-dependent Sox9 expression in tracheal cartilage

    PubMed Central

    Lin, Shin-Shiou; Tzeng, Bing-Hsiean; Lee, Kuan-Rong; Smith, Richard J. H.; Campbell, Kevin P.; Chen, Chien-Chang

    2014-01-01

    Intracellular Ca2+ transient is crucial in initiating the differentiation of mesenchymal cells into chondrocytes, but whether voltage-gated Ca2+ channels are involved remains uncertain. Here, we show that the T-type voltage-gated Ca2+ channel Cav3.2 is essential for tracheal chondrogenesis. Mice lacking this channel (Cav3.2−/−) show congenital tracheal stenosis because of incomplete formation of cartilaginous tracheal support. Conversely, Cav3.2 overexpression in ATDC5 cells enhances chondrogenesis, which could be blunted by both blocking T-type Ca2+ channels and inhibiting calcineurin and suggests that Cav3.2 is responsible for Ca2+ influx during chondrogenesis. Finally, the expression of sex determination region of Y chromosome (SRY)-related high-mobility group-Box gene 9 (Sox9), one of the earliest markers of committed chondrogenic cells, is reduced in Cav3.2−/− tracheas. Mechanistically, Ca2+ influx via Cav3.2 activates the calcineurin/nuclear factor of the activated T-cell (NFAT) signaling pathway, and a previously unidentified NFAT binding site is identified within the mouse Sox9 promoter using a luciferase reporter assay and gel shift and ChIP studies. Our findings define a previously unidentified mechanism that Ca2+ influx via the Cav3.2 T-type Ca2+ channel regulates Sox9 expression through the calcineurin/NFAT signaling pathway during tracheal chondrogenesis. PMID:24778262

  16. Modulating Wnt Signaling Pathway to Enhance Allograft Integration in Orthopedic Trauma Treatment

    DTIC Science & Technology

    2014-04-01

    DKK1 with monoclonal antibodies will enhance allograft integration to the host bone. The proposed work in this project was designed to test this...of modulating the LRP-5/Wnt pathway with anti- Dkk1 monoclonal antibody on allograft incorporation in a rat segmental repair model using radiographical...Frozen and Freeze-Dried allografts at 4, 8 and 12 week time points for saline, anti- Sost and anti- Dkk1 using µCT scanning. Data is presented below

  17. Macrophage-to-Myofibroblast Transition Contributes to Interstitial Fibrosis in Chronic Renal Allograft Injury.

    PubMed

    Wang, Ying-Ying; Jiang, Hong; Pan, Jun; Huang, Xiao-Ru; Wang, Yu-Cheng; Huang, Hong-Feng; To, Ka-Fai; Nikolic-Paterson, David J; Lan, Hui-Yao; Chen, Jiang-Hua

    2017-02-16

    Interstitial fibrosis is an important contributor to graft loss in chronic renal allograft injury. Inflammatory macrophages are associated with fibrosis in renal allografts, but how these cells contribute to this damaging response is not clearly understood. Here, we investigated the role of macrophage-to-myofibroblast transition in interstitial fibrosis in human and experimental chronic renal allograft injury. In biopsy specimens from patients with active chronic allograft rejection, we identified cells undergoing macrophage-to-myofibroblast transition by the coexpression of macrophage (CD68) and myofibroblast (α-smooth muscle actin [α-SMA]) markers. CD68(+)/α-SMA(+) cells accounted for approximately 50% of the myofibroblast population, and the number of these cells correlated with allograft function and the severity of interstitial fibrosis. Similarly, in C57BL/6J mice with a BALB/c renal allograft, cells coexpressing macrophage markers (CD68 or F4/80) and α-SMA composed a significant population in the interstitium of allografts undergoing chronic rejection. Fate-mapping in Lyz2-Cre/Rosa26-Tomato mice showed that approximately half of α-SMA(+) myofibroblasts in renal allografts originated from recipient bone marrow-derived macrophages. Knockout of Smad3 protected against interstitial fibrosis in renal allografts and substantially reduced the number of macrophage-to-myofibroblast transition cells. Furthermore, the majority of macrophage-to-myofibroblast transition cells in human and experimental renal allograft rejection coexpressed the M2-type macrophage marker CD206, and this expression was considerably reduced in Smad3-knockout recipients. In conclusion, our studies indicate that macrophage-to-myofibroblast transition contributes to interstitial fibrosis in chronic renal allograft injury. Moreover, the transition of bone marrow-derived M2-type macrophages to myofibroblasts in the renal allograft is regulated via a Smad3-dependent mechanism.

  18. Selection of massive bone allografts using shape-matching 3-dimensional registration

    PubMed Central

    Docquier, Pierre-Louis; Cartiaux, Olivier; Cornu, Olivier; Delloye, Christian; Banse, Xavier

    2010-01-01

    Background and purpose Massive bone allografts are used when surgery causes large segmental defects. Shape-matching is the primary criterion for selection of an allograft. The current selection method, based on 2-dimensional template comparison, is inefficient for 3-dimensional complex bones. We have analyzed a 3-dimensional (3-D) registration method to match the anatomy of the allograft with that of the recipient. Methods 3-D CT-based registration was performed to match the shapes of both bones. We used the registration to align the allograft volume onto the recipient's bone. Hemipelvic allograft selection was tested in 10 virtual recipients with a panel of 10 potential allografts, including one from the recipient himself (trap graft). 4 observers were asked to visually inspect the superposition of allograft over the recipient, to classify the allografts into 4 categories according to the matching of anatomic zones, and to select the 3 best matching allografts. The results obtained using the registration method were compared with those from a previous study on the template method. Results Using the registration method, the observers systematically detected the trap graft. Selections of the 3 best matching allografts performed using registration and template methods were different. Selection of the 3 best matching allografts was improved by the registration method. Finally, reproducibility of the selection was improved when using the registration method. Interpretation 3-D CT registration provides more useful information than the template method but the final decision lies with the surgeon, who should select the optimal allograft according to his or her own preferences and the needs of the recipient. PMID:20175643

  19. Caveolin-1 (CAV1) is a target of EWS/FLI-1 and a key determinant of the oncogenic phenotype and tumorigenicity of Ewing's sarcoma cells.

    PubMed

    Tirado, Oscar M; Mateo-Lozano, Silvia; Villar, Joaquín; Dettin, Luis E; Llort, Anna; Gallego, Soledad; Ban, Jozef; Kovar, Heinrich; Notario, Vicente

    2006-10-15

    Tumors of the Ewing's sarcoma family (ESFT), such as Ewing's sarcoma (EWS) and primitive neuroectodermal tumors (PNET), are highly aggressive malignancies predominantly affecting children and young adults. ESFT express chimeric transcription factors encoded by hybrid genes fusing the EWS gene with several ETS genes, most commonly FLI-1. EWS/FLI-1 proteins are responsible for the malignant phenotype of ESFT, but only few of their transcriptional targets are known. Using antisense and short hairpin RNA-mediated gene expression knockdown, array analyses, chromatin immunoprecipitation methods, and reexpression studies, we show that caveolin-1 (CAV1) is a new direct target of EWS/FLI-1 that is overexpressed in ESFT cell lines and tumor specimens and is necessary for ESFT tumorigenesis. CAV1 knockdown led to up-regulation of Snail and the concomitant loss of E-cadherin expression. Consistently, loss of CAV1 expression inhibited the anchorage-independent growth of EWS cells and markedly reduced the growth of EWS cell-derived tumors in nude mice xenografts, indicating that CAV1 promotes the malignant phenotype in EWS carcinogenesis. Reexpression of CAV1 or E-cadherin in CAV1 knockdown EWS cells rescued the oncogenic phenotype of the original EWS cells, showing that the CAV1/Snail/E-cadherin pathway plays a central role in the expression of the oncogenic transformation functions of EWS/FLI-1. Overall, these data identify CAV1 as a key determinant of the tumorigenicity of ESFT and imply that targeting CAV1 may allow the development of new molecular therapeutic strategies for ESFT patients.

  20. Imaging-based diagnosis of acute renal allograft rejection

    PubMed Central

    Thölking, Gerold; Schuette-Nuetgen, Katharina; Kentrup, Dominik; Pawelski, Helga; Reuter, Stefan

    2016-01-01

    Kidney transplantation is the best available treatment for patients with end stage renal disease. Despite the introduction of effective immunosuppressant drugs, episodes of acute allograft rejection still endanger graft survival. Since efficient treatment of acute rejection is available, rapid diagnosis of this reversible graft injury is essential. For diagnosis of rejection, invasive core needle biopsy of the graft is the “gold-standard”. However, biopsy carries the risk of significant graft injury and is not immediately feasible in patients taking anticoagulants. Therefore, a non-invasive tool assessing the whole organ for specific and fast detection of acute allograft rejection is desirable. We herein review current imaging-based state of the art approaches for non-invasive diagnostics of acute renal transplant rejection. We especially focus on new positron emission tomography-based as well as targeted ultrasound-based methods. PMID:27011915

  1. Total lymphoid irradiation for treatment of intractable cardiac allograft rejection

    SciTech Connect

    Hunt, S.A.; Strober, S.; Hoppe, R.T.; Stinson, E.B. )

    1991-03-01

    The ability of postoperative total lymphoid irradiation to reverse otherwise intractable cardiac allograft rejection was examined in a group of 10 patients in whom conventional rejection therapy (including pulsed steroids and monoclonal or polyclonal anti-T-cell antibody therapy) had failed to provide sustained freedom from rejection. Follow-up periods range from 73 to 1119 days since the start of total lymphoid irradiation. No patient died or sustained serious morbidity because of the irradiation. Three patients have had no further rejection (follow-up periods, 105 to 365 days). Two patients died--one in cardiogenic shock during the course of total lymphoid irradiation, the other with recurrent rejection caused by noncompliance with his medical regimen. Total lymphoid irradiation appears to be a safe and a moderately effective immunosuppressive modality for 'salvage' therapy of cardiac allograft rejection unresponsive to conventional therapy.

  2. The Tips and Pitfalls of Meniscus Allograft Transplantation

    PubMed Central

    Lee, Sung Rak; Nam, Sang Wook

    2012-01-01

    When faced with an irrepairable meniscus or a patient who has had a total or subtotal meniscectomy, meniscus allograft transplantation (MAT) is the preferred modality to restore biomechanical function of the meniscus. The indications for meniscus allograft transplantation are yet to be established. However, currently, MAT has previously been indicated for symptomatic patients who have mild or early osteoarthritis, are younger than 50 years of age, and present with an Outerbridge grade II or lower. The short- to intermediate-term results confirmed noteworthy clinical improvements and consistent objective findings. On the other hand, the successful outcome would be reduced by various complications. Therefore, long-term observation required to evaluate the longevity of these results. The purpose of this article is to review the current research of concerns on the results of MAT, and to describe the technical tips and pitfalls so as to successful clinical results. PMID:22977790

  3. Creeping attachment: autogenous graft vs dermal matrix allograft.

    PubMed

    Haeri, A; Parsell, D

    2000-09-01

    For many years, free autogenous grafts have been used as a method of gaining keratinized tissue around teeth with mucogingival problems. Creeping attachment using autogenous graft material has been actively studied. In addition, biocompatible, acellular connective-tissue material has recently been used as an alternative to free gingival grafts to increase the zone of keratinization. This report presents a patient with bilateral mucogingival defects in the canine and premolar areas. The patient received an autogenous graft on one side and a dermal matrix allograft on the contralateral side. Creeping attachments were measured and compared at 3 months and 12 months after surgery. After 12 months of healing, an average of 1.23 mm of creeping attachment was measured on the free gingival graft side and 0.96 mm of creeping attachment was measured with the dermal matrix allograft.

  4. Chest wall reconstruction using iliac bone allografts and muscle flaps.

    PubMed

    Garcia-Tutor, Emilio; Yeste, Luis; Murillo, Julio; Aubá, Cristina; Sanjulian, Mikel; Torre, Wenceslao

    2004-01-01

    Technically we can divide full-thickness thoracic reconstruction into 2 parts: providing a rigid support and ensuring well-vascularized coverage. Since 1986, the authors' center has had ample experience with bone banks and the use of cryopreserved bone grafts, which led them to consider the possibility of using these grafts for full-thickness chest wall reconstruction. They describe 3 patients in whom resection of the tumor and reconstruction of the thorax were carried out using iliac bone allografts covered with muscle flaps (1 pectoralis major and 2 rectus abdominis). None of the patients experienced breathing difficulties, pain, or instability after 14 months, 18 months, and 11 years of follow-up. The result of the reconstruction was excellent in all 3 patients in terms of function and aesthetics. The advantage of allografts compared with synthetic materials is their potential integration; they can become part of the host patient's living tissue.

  5. Human renal allograft blood flow and early renal function.

    PubMed Central

    Anderson, C B; Etheredge, E E

    1977-01-01

    Renal allograft blood flow (RBF) was measured at operation by electromagnetic flow meter and probes in 45 patients (34 cadaver donors and 11 living related donors). Mean RBF in 26 patients without acute tubular necrosis (ATN), was 412 +/- 80 ml/min and in 19 patients with ATN, 270 +/- 100 ml/min (p less than .001). Only two of 24 transplants (8%) with RBF greater than 350 ml/min had ATN; whereas, 17 of 21 transplants (81 per cent) with RBF less than 350 ml/min had ATN (p less than .001). In cadaver donor transplants, RBF did not correlate with duration of ATN, warm ischemia time, total ischemia time, pulsatile perfusion time or renal vascular resistance during perfusion. Measurement of renal allograft blood flow can predict presence or absence of postoperative ATN in 87% of patients. PMID:335986

  6. Prolongation of segmental and pancreaticoduodenal allografts in the primate with total-lymphoid irradiation and cyclosporine

    SciTech Connect

    Du Toit, D.F.; Heydenrych, J.J.; Smit, B.; Louw, G.; Zuurmond, T.; Els, D.; Du Toit, L.B.; Weideman, A.; Davids, H.; van der Merwe, E.

    1987-09-01

    The prolongation of segmental and pancreaticoduodenal allografts (PDA) by total lymphoid irradiation (TLI) and in combination with cyclosporine (CsA) was assessed in a well established total pancreatectomy, diabetic, primate transplantation model. Pancreatic transplantation was performed in 119 pancreatectomized baboons (Papio ursinus). Of a total of 109 allografts performed, 71 were segmental allografts (open duct drainage) and 38 PDA. Of 119 graft recipients, 10 received segmental pancreatic autografts. TLI and CsA administered separately to segmental allograft recipients resulted in modest allograft survival and indefinite graft survival was not observed. 8 of 17 (47%) segmental allograft recipients that received TLI and CsA had graft survival beyond 100 days, indicating highly significant pancreatic allograft survival. All long-term segmental allograft recipients were rendered normoglycemic (plasma glucose less than 8 mmol/L) by this immunosuppressive regimen. In contrast, poor results were observed in PDA recipients treated with TLI and CsA. Mean survival in 18 treated PDA recipients was 23.8 days, 8 survived longer than 20 days (44.4%), and 1 greater than 100 days (5.5%). Despite treatment, early rejection of the duodenum in PDA recipients frequently resulted in necrosis and perforation and contributed to a high morbidity and mortality. This study indicates that, in contrast to the significant prolongation of segmental allografts by TLI and CsA, poor immunosuppression was achieved by this regimen in PDA recipients and was associated with a high morbidity and mortality caused by early rejection of the duodenum.

  7. Quantitative podocyte parameters predict human native kidney and allograft half-lives

    PubMed Central

    Naik, Abhijit S.; Afshinnia, Farsad; Cibrik, Diane; Hodgin, Jeffrey B.; Zhang, Min; Kikuchi, Masao; Wickman, Larysa; Samaniego, Milagros; Bitzer, Markus; Wiggins, Jocelyn E.; Ojo, Akinlolu; Li, Yi; Wiggins, Roger C.

    2016-01-01

    BACKGROUND. Kidney function decreases with age. A potential mechanistic explanation for kidney and allograft half-life has evolved through the realization that linear reduction in glomerular podocyte density could drive progressive glomerulosclerosis to impact both native kidney and allograft half-lives. METHODS. Predictions from podometrics (quantitation of podocyte parameters) were tested using independent pathologic, functional, and outcome data for native kidneys and allografts derived from published reports and large registries. RESULTS. With age, native kidneys exponentially develop glomerulosclerosis, reduced renal function, and end-stage kidney disease, projecting a finite average kidney life span. The slope of allograft failure rate versus age parallels that of reduction in podocyte density versus age. Quantitative modeling projects allograft half-life at any donor age, and rate of podocyte detachment parallels the observed allograft loss rate. CONCLUSION. Native kidneys are designed to have a limited average life span of about 100–140 years. Allografts undergo an accelerated aging-like process that accounts for their unexpectedly short half-life (about 15 years), the observation that older donor age is associated with shorter allograft half-life, and the fact that long-term allograft survival has not substantially improved. Podometrics provides potential readouts for these processes, thereby offering new approaches for monitoring and intervention. FUNDING: National Institutes of Health. PMID:27280173

  8. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  9. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  10. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  11. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  12. 21 CFR 862.1163 - Cardiac allograft gene expression profiling test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems § 862.1163 Cardiac allograft gene expression profiling test system....

  13. Fresh-frozen Complete Extensor Mechanism Allograft versus Autograft Reconstruction in Rabbits

    PubMed Central

    Chen, Guanyin; Zhang, Hongtao; Ma, Qiong; Zhao, Jian; Zhang, Yinglong; Fan, Qingyu; Ma, Baoan

    2016-01-01

    Different clinical results have been reported in the repair of extensor mechanism disruption using fresh-frozen complete extensor mechanism (CEM) allograft, creating a need for a better understanding of fresh-frozen CME allograft reconstruction. Here, we perform histological and biomechanical analyses of fresh-frozen CEM allograft or autograft reconstruction in an in vivo rabbit model. Our histological results show complete incorporation of the quadriceps tendon into the host tissues, patellar survival and total integration of the allograft tibia, with relatively fewer osteocytes, into the host tibia. Vascularity and cellularity are reduced and delayed in the allograft but exhibit similar distributions to those in the autograft. The infrapatellar fat pad provides the main blood supply, and the lowest cellularity is observed in the patellar tendon close to the tibia in both the allograft and autograft. The biomechanical properties of the junction of quadriceps tendon and host tissues and those of the allograft patellar tendon are completely and considerably restored, respectively. Therefore, fresh-frozen CEM allograft reconstruction is viable, but the distal patellar tendon and the tibial block may be the weak links of the reconstruction. These findings provide new insight into the use of allograft in repairing disruption of the extensor mechanism. PMID:26911538

  14. Retrieval of the pancreas allograft for whole-organ transplantation.

    PubMed

    Fridell, Jonathan A; Powelson, John A; Kubal, Chandrashekhar A; Burke, George W; Sageshima, Junichiro; Rogers, Jeffrey; Stratta, Robert J

    2014-12-01

    Proper pancreas retrieval during multi-organ recovery is one of the cornerstones of technically successful whole-organ pancreas transplantation. With evolving surgical approaches for organ retrieval and implantation, it has become standard to procure the pancreas in conjunction with other abdominal organs without compromising either vasculature, graft quality, or transplant outcomes. This review summarizes the major steps required for proper whole-organ retrieval of the pancreas allograft with suggestions and tips whenever alternative approaches are available.

  15. Redetermination of metarossite, CaV5+ 2O6·2H2O

    PubMed Central

    Kobsch, Anaïs; Downs, Robert T.; Domanik, Kenneth J.

    2016-01-01

    The crystal structure of metarossite, ideally CaV2O6·2H2O [chemical name: calcium divanadium(V) hexa­oxide dihydrate], was first determined using precession photographs, with fixed isotropic displacement parameters and without locating the positions of the H atoms, leading to a reliability factor R = 0.11 [Kelsey & Barnes (1960 ▸). Can. Mineral. 6, 448–466]. This communication reports a structure redetermination of this mineral on the basis of single-crystal X-ray diffraction data of a natural sample from the Blue Cap mine, San Juan County, Utah, USA (R1 = 0.036). Our study not only confirms the structural topology reported in the previous study, but also makes possible the refinement of all non-H atoms with anisotropic displacement parameters and all H atoms located. The metarossite structure is characterized by chains of edge-sharing [CaO8] polyhedra parallel to [100] that are themselves connected by chains of alternating [VO5] trigonal bipyramids parallel to [010]. The two H2O mol­ecules are bonded to Ca. Analysis of the displacement parameters show that the [VO5] chains librate around [010]. In addition, we measured the Raman spectrum of metarossite and compared it with IR and Raman data previously reported. Moreover, heating of metarossite led to a loss of water, which results in a transformation to the brannerite-type structure, CaV2O6, implying a possible dehydration pathway for the compounds M 2+V2O6·xH2O, with M = Cu, Cd, Mg or Mn, and x = 2 or 4. PMID:27920917

  16. Prevention of allograft tolerance by bacterial infection with Listeria monocytogenes

    PubMed Central

    Wang, Tongmin; Chen, Luqiu; Ahmed, Emily; Ma, Lianli; Yin, Dengping; Zhou, Ping; Shen, Jikun; Xu, Honglin; Wang$, Chyung-Ru; Alegre, Maria-Luisa

    2008-01-01

    Exposure to certain viruses and parasites has been shown to prevent the induction of transplantation tolerance in mice, via generation of cross-reactive memory T cell responses or induction of bystander activation. Bacterial infections are common in the peri-operative period of solid organ allograft recipients in the clinic, and correlations between bacterial infections and acute allograft rejection have been reported. However, whether bacterial infections at the time of transplantation have any effect on the generation of transplantation tolerance remains to be established. We used the Gram-positive intracellular bacterium Listeria monocytogenes (LM) as a model pathogen, as its effects on immune responses are well described. Peri-operative LM infection prevented cardiac and skin allograft acceptance induced by anti-CD154 and donor-specific transfusion (DST) in mice. LM-mediated rejection was not due to the generation of cross-reactive T cells and was largely independent of signaling via MyD88, an adaptor for most toll-like receptors (TLRs), IL-1 and IL-18. Instead, transplant rejection following LM infection was dependent on the expression of the phagosome-lysing pore-former listeriolysin O (LLO) and on IFNα/βR signaling. Our results indicate that bacterial exposure at the time of transplantation can antagonize tolerogenic regimens by enhancing alloantigen-specific immune responses, independent from the generation of cross-reactive memory T cells. PMID:18424719

  17. STAT4 gene polymorphism in patients after renal allograft transplantation

    PubMed Central

    Dąbrowska-Żamojcin, Ewa; Dziedziejko, Violetta; Safranow, Krzysztof; Domański, Leszek; Słuczanowska-Głabowska, Sylwia

    2016-01-01

    Introduction STAT4 (signal transducer and activator of transcription 4) is involved in the regulation of innate and adaptive immune responses. Some studies have suggested that STAT4 may be involved in the immune response after graft transplantation. Several polymorphisms in the STAT4 gene have been identified. The most commonly studied polymorphism in the STAT4 gene is rs7574865. In our study, we examined whether this polymorphism is associated with the early and late functions of renal allografts. Material and methods A total of 270 recipients of first renal transplants were included in the study. Single nucleotide polymorphisms (SNPs) within the STAT4 gene were genotyped using TaqMan genotyping assays. Results There were no statistically significant associations between the STAT4 gene rs7574865 polymorphism and delayed graft function, acute rejection, chronic allograft dysfunction, post-transplant diabetes mellitus, or creatinine serum concentrations after transplantation. Conclusions Our results suggest a lack of association between the STAT4 rs7574865 SNP and kidney allograft function in the Polish population. PMID:27833442

  18. Impact of freezing on immunology and incorporation of bone allograft.

    PubMed

    Reikerås, Olav; Sigurdsen, Ulf W; Shegarfi, Hamid

    2010-09-01

    With an increasing clinical use of deep frozen allograft for bone reconstruction, it is important to understand the immunological and biological events of allograft incorporation. In this study, we have investigated the impact of deep freezing on immunology and biopotency for incorporation of bone allografts. Deep frozen bone grafts matched or mismatched for major histoscompatibilty complex (MHC) were implanted in an 8-mm segmental defect in the tibia in rats. The construct was stabilized with intramedullary nailing. The immune response was evaluated by determination of serum antibody against the grafts MHC molecules at day 1 and after 2 and 4 months. Incorporation of the graft was compared with fresh syngeneic grafts and assessed with the use of conventional radiography, biomechanical testing and measurement of bone mineral content and density after 4 months. The analyses revealed no antibody responses in the rats that received grafts from donors differing at histocompatibility loci, and at 4 months the frozen grafts showed an overall reconstruction that was not significantly different from the fresh grafts. This study indicates that in the long run there are no significant consequences; either immunological or biomechanical, of the use of deep frozen allogenous bone as compared to fresh autogenous bone grafts in this animal model.

  19. Renal allograft tuberculosis with infected lymphocele transmitted from the donor.

    PubMed

    Al-Nesf, Maryam Ali; Al-Ani, Omar Isam; Al-Ani, Ahmed Abdul-Rahman; Rashed, Awad Hamed

    2014-03-01

    Transmission of tuberculosis (TB) from a donor through renal transplantation is a rare incident. We are reporting a 53-year-old Qatari woman diagnosed with renal allograft TB infection. The disease was confirmed by isolation of Mycobacterium tuberculosis from fluid from the lymphocele and demonstration of caseating granuloma in graft biopsy with acid-fast bacilli seen on Ziehl-Neelsen staining. The diagnosis was made quite early post-transplantation. The presence of the granuloma, which is unusual with patients on intensive immunosuppressant medications, suggests that transmission of the infection occurred from the donor rather than from the activation of latent infection. In reviewing the literature, we found ten case reports of TB in transplanted kidney with transmission of TB infection from the donor. The presence of TB in lymphocele in association with the infected transplant by TB, to the best of our knowledge, was reported only once in the literature. Our case had unfavorable outcome and ended by renal allograft nephrectomy and hemodialysis. We are presenting this case of TB infection of renal allograft and lymphocele diagnosed early post-transplantation transmitted from the donor and pertinent review from the literature.

  20. Immunohistochemical Investigation of the Heart Allograft Myocardium (1991-1998).

    PubMed

    Beletskaya, Ludmila V.; Baranova, Flora S.; Khalimova, Zarema A.; Zaidenov, Vladimir A.; Kurenkova, Lubov G.; Kormer, Arkadiy Ya.; Khubutia, Anzor Sh.; Kupriyanova, Anna G.; Shumakov, Valeriy I.

    2000-04-01

    What is a contribution of the humoral (vascular) and mixed type of the rejection episodes to all the episodes of heart allograft rejection is not quite clear, though this factor is of considerable importance for the choice of the treatment methods. The hearts from recipients, as well as endomyocardial biopsies of the heart allografts and postmortem material were investigated with the aim to determine the immunopathological process. Overall, 420 samples from 80 patients were analyzed. Immunofluorescence examination of endomyocardial biopsy showed that in 8 from 44 patients with heart allograft in postoperative period for the first six weeks there were revealed the immunomorphological signs of the acute humoral rejection, manifested as fixation of immunoglobulins and complement in capillaries. Six of them exhibited rejection of mixed type. Most patients in the later postoperative period exhibited a discrete local fixation of immunoglobulins and complement in myocardium, that can be assessed as one of the compartments of the chronic rejection process. In cases of the secondary administration of serum preparations, the fixation of immune complexes was shown in sarcolemma and capillaries, and can be proposed as a sign of serum disease. Repeated acute rejection episodes of humoral or mixed types raised at the first six weeks after transplantation. In the period from 1-5 years after operation, patients displayed discrete deposits of the immunoglobulins and complement as part of the chronic rejection process.

  1. Allograft Heart Valves: Current Aspects and Future Applications.

    PubMed

    Lisy, Milan; Kalender, Guenay; Schenke-Layland, Katja; Brockbank, Kelvin G M; Biermann, Anna; Stock, Ulrich Alfred

    2017-02-02

    Human heart valve allografts continue to represent almost perfect substitutes for heart valves. They have optimal hemodynamic characteristics and are highly resistant to infections. The first clinical use of allograft heart valves was as homovitals being transplanted after antibiotic incubation without any preservation. Since 1968, relatively standardized frozen cryopreservation (SFC) has been employed, including storage in vapor-phase liquid nitrogen. Disadvantages, particularly in pediatric patients, are limited availability due to organ scarcity, inability to grow, degeneration, immune response, and long-term failure. However, in contrast to alternative prosthetic or bioprosthetic heart valve replacements, they represent the best pediatric and juvenile replacement options for the pulmonary valve. Application of multiphoton imaging analysis for three-dimensional visualization of elastin and collagen by induction of autofluorescence without chemical fixation, embedding, and staining has revealed partial destruction of elastic and collagenous matrix in SFC valves. As the overall amount of collagen and elastin remains unchanged, the observed destruction is attributed to freezing-induced extracellular matrix damages due to ice crystal formation during SFC. The objective of this review is an assessment of current allograft preservation methods and the potential of novel preservation techniques to avoid ice formation with accompanied better long-term function.

  2. Gr-1intCD11b+ myeloid-derived suppressor cells accumulate in corneal allograft and improve corneal allograft survival.

    PubMed

    Choi, Wungrak; Ji, Yong Woo; Ham, Hwa-Yong; Yeo, Areum; Noh, Hyemi; Jin, Su-Eon; Song, Jong Suk; Kim, Hyeon Chang; Kim, Eung Kwon; Lee, Hyung Keun

    2016-12-01

    We identified the characteristics of myeloid-derived suppressor cells (MDSCs) and investigated their mechanism of induction and their functional role in allograft rejection using a murine corneal allograft model. In mice, MDSCs coexpress CD11b and myeloid differentiation antigen Gr-1. Gr-1(+)CD11b(+) cells infiltrated allografted corneas between 4 d and 4 wk after surgery; however, the frequencies of Gr-1(+)CD11b(+) cells were not different between accepted and rejected allografts or in peripheral blood or BM. Of interest, Gr-1(int)CD11b(+) cells, but not Gr-1(hi)CD11b(+) cells, infiltrated the accepted graft early after surgery and expressed high levels of immunosuppressive cytokines, including IL-10, TGF-β, and TNF-related apoptosis-inducing ligand. This population remained until 4 wk after surgery. In vitro, only high dose (>100 ng/ml) of IFN-γ plus GM-CSF could induce immunosuppressive cytokine expression in Gr-1(int)CD11b(+) cells. Furthermore, adoptive transfer of Gr-1(int)CD11b(+) cells reduced T cell infiltration, which improved graft survival. In conclusion, high-dose IFN-γ in allograft areas is essential for development of Gr-1(int)CD11b(+) MDSCs in corneal allografts, and subtle environmental changes in the early period of the allograft can result in a large difference in graft survival.

  3. Usefulness of Diastolic Strain Measurements in Predicting Elevated Left Ventricular Filling Pressure and Risk of Rejection or Coronary Artery Vasculopathy in Pediatric Heart Transplant Recipients.

    PubMed

    Lu, Jimmy C; Magdo, H Sonali; Yu, Sunkyung; Lowery, Ray; Aiyagari, Ranjit; Zamberlan, Mary; Gajarski, Robert J

    2016-05-01

    In pediatric heart transplant recipients, elevated pulmonary capillary wedge pressure (PCWP) is associated with rejection and coronary artery vasculopathy. This study aimed to evaluate which echocardiographic parameters track changes in PCWP and predict adverse outcomes (rejection or coronary artery vasculopathy). This prospective single-center study enrolled 49 patients (median 11.4 years old, interquartile range 7.4 to 16.5) at time of cardiac catheterization and echocardiography. Median follow-up was 2.4 years (range 1.2 to 3.1 years), with serial testing per clinical protocol. Ratio of early mitral inflow to annular velocity (E/E'), left atrial (LA) distensibility, peak LA systolic strain, E/left ventricular (LV) diastolic strain, and E/LV diastolic strain rate were measured from echocardiograms. Increase in PCWP ≥3 mm Hg was associated with changes in LA distensibility, E/E', and E/LV diastolic strain, with highest area under the receiver operating characteristic curve for E/LV diastolic strain (0.76). In 9 patients who subsequently developed rejection or coronary artery vasculopathy, E/LV diastolic strain rate at baseline differed from patients without events (median 57.0 vs 43.6, p = 0.02). On serial studies, only change in LV ejection fraction differed in patients with events (median -10% vs -1%, p = 0.01); decrease in LV ejection fraction of -19% had a specificity of 100% and sensitivity of 44%. In conclusion, LV diastolic strain and strain rate measurements can track changes in PCWP and identify patients at risk for subsequent rejection or coronary artery vasculopathy. Further studies are necessary to confirm these data in a larger cohort.

  4. Fresh vein allograft survival in dogs after cyclosporine treatment.

    PubMed

    Mingoli, A; Edwards, J D; Feldhaus, R J; Hunter, W J; Naspetti, R; Cavallari, N; Sapienza, P; Kretchmar, D H; Cavallaro, A

    1996-04-01

    Synthetic grafts are widely used for peripheral arterial reconstructions when autologous veins are not available, but their results have not been satisfactory. Venous allograft may be used as an alternative to synthetic prostheses. The aim of the study was to explore the immunosuppressive efficacy of Cyclosporine A (CyA) as a means of preventing venous allograft failures and rejection. We utilized 56 mongrel dogs. Immunological incompatibility was checked with the skin graft method. Donor inferior vena cava was transplanted into the infrarenal abdominal aorta of recipient animals. One group (group 1, 10 dogs) served as a control and three groups received CyA treatment regimens. Group 2 (10 dogs) received postoperative oral CyA treatment for 30 days. Group 3 (12 dogs) received a vein graft pretreated with a CyA solution without postoperative immunosuppressive therapy. Group 4 (9 dogs) received a vein graft pretreated with a CyA solution and postoperative CyA treatment for 30 days. Allografts were examined at 30 days for patency, aneurysmal dilatation, gross structural changes, inflammatory response, and lymphocytic infiltration. Sex chromatine assessment determined the origin (donor or recipient) of the endothelial cells. The allografts from groups 1 and 3 showed significant aneurysmal dilatation and perivenous inflammation when compared to dogs treated with oral CyA therapy (P < 0.0002). Moreover allografts treated with CyA therapy had a better-developed venous neointima (P < 0.009) with less fibrin (P < 0.02) and thinner medial (P < 0.0009) with less fibrin (P < 0.02), and thinner medial (P < 0.0009) and adventitial layers (P < 0.02). No significant differences were observed in neointimal thickness among the four groups. Lymphocytic infiltration was greater in the group of animals who did not receive oral CyA therapy (P < 0.0004). Barr bodies status showed significant differences between oral CyA treated groups and nontreated groups (P < 0.0003). Oral CyA therapy

  5. In vitro allograft irradiation prevents graft-versus-host disease in small-bowel transplantation

    SciTech Connect

    Lee, K.K.; Schraut, W.H.

    1985-04-01

    In small-bowel transplantation, the transfer of large numbers of donor lymphocytes with the intestinal allograft may provoke a lethal graft-versus-host reaction. The effectiveness of allograft irradiation in vitro as a method of preventing graft-versus-host disease (GVHD) was studied in a rat model of small-bowel transplantation, with the Lewis----Lewis X Brown Norway F1 hybrid strain combination. Cold harvested small-bowel allografts were irradiated immediately prior to heterotopic or orthotopic transplantation. Animals that had received heterotopic allografts irradiated with 0, 250, or 500 rad all died of GVHD after 14.4 +/- 3.0, 15.0 +/- 1.3, and 14.2 +/- 1.9 days, respectively. None of the animals that had received allografts treated with 1000 rad developed clinical or pathologic evidence of GVHD, however, and all survived for more than 6 months (P less than 0.001). Allograft function was studied in animals that underwent orthotopic transplantation. Recipients of nonirradiated orthotopic allografts all died of GVHD after 14.0 +/- 0.7 days, whereas recipients of allografts irradiated with 1000 rad all survived for more than 5 months (P less than 0.001). After 120 days, weight gain (51.8 +/- 11.7%), serum albumin (3.9 +/- 0.7 g/dl), serum triglycerides (67.0 +/- 24.3 mg/dl), CBC, and differential in these animals were not statistically different from those in either age-matched isograft recipients or normal animals, and when the rats were sacrificed, irradiated allografts showed no changes suggestive of radiation injury. These results indicate that irradiation of small-bowel allografts in vitro prevents development of GVHD, and that this can be achieved at a dose which does not cause injury to or malfunction of the allograft.

  6. Optimization of the genomic DNA extraction method of silverleaf nightshade/ (Solanum elaeagnifolium /Cav.), an invasive plant in the cultivated areas within the Mediterranean region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The geographical origin of an invasive in the cultivated area within the Mediterranean region, silverleaf nightshade, Solanum elaeagnifolium Cav, (Solanaceae) should be identified through the analysis of genetic similarities between native and introduced populations using microsatellite markers. Bef...

  7. Endogenous and exogenous hydrogen sulfide facilitates T-type calcium channel currents in Cav3.2-expressing HEK293 cells.

    PubMed

    Sekiguchi, Fumiko; Miyamoto, Yosuke; Kanaoka, Daiki; Ide, Hiroki; Yoshida, Shigeru; Ohkubo, Tsuyako; Kawabata, Atsufumi

    2014-02-28

    Hydrogen sulfide (H2S), a gasotransmitter, is formed from l-cysteine by multiple enzymes including cystathionine-γ-lyase (CSE). We have shown that an H2S donor, NaHS, causes hyperalgesia in rodents, an effect inhibited by knockdown of Cav3.2 T-type Ca(2+) channels (T-channels), and that NaHS facilitates T-channel-dependent currents (T-currents) in NG108-15 cells that naturally express Cav3.2. In the present study, we asked if endogenous and exogenous H2S participates in regulation of the channel functions in Cav3.2-transfected HEK293 (Cav3.2-HEK293) cells. dl-Propargylglycine (PPG), a CSE inhibitor, significantly decreased T-currents in Cav3.2-HEK293 cells, but not in NG108-15 cells. NaHS at 1.5mM did not affect T-currents in Cav3.2-HEK293 cells, but enhanced T-currents in NG108-15 cells. In the presence of PPG, NaHS at 1.5mM, but not 0.1-0.3mM, increased T-currents in Cav3.2-HEK293 cells. Similarly, Na2S, another H2S donor, at 0.1-0.3mM significantly increased T-currents in the presence, but not absence, of PPG in Cav3.2-HEK293 cells. Expression of CSE was detected at protein and mRNA levels in HEK293 cells. Intraplantar administration of Na2S, like NaHS, caused mechanical hyperalgesia, an effect blocked by NNC 55-0396, a T-channel inhibitor. The in vivo potency of Na2S was higher than NaHS. These results suggest that the function of Cav3.2 T-channels is tonically enhanced by endogenous H2S synthesized by CSE in Cav3.2-HEK293 cells, and that exogenous H2S is capable of enhancing Cav3.2 function when endogenous H2S production by CSE is inhibited. In addition, Na2S is considered a more potent H2S donor than NaHS in vitro as well as in vivo.

  8. Rab27a GTPase modulates L-type Ca2+ channel function via interaction with the II-III linker of CaV1.3 subunit.

    PubMed

    Reichhart, Nadine; Markowski, Magdalena; Ishiyama, Shimpei; Wagner, Andrea; Crespo-Garcia, Sergio; Schorb, Talitha; Ramalho, José S; Milenkovic, Vladimir M; Föckler, Renate; Seabra, Miguel C; Strauß, Olaf

    2015-11-01

    In a variety of cells, secretory processes require the activation of both Rab27a and L-type channels of the Ca(V)1.3 subtype. In the retinal pigment epithelium (RPE), Rab27a and Ca(V)1.3 channels regulate growth-factor secretion towards its basolateral side. Analysis of murine retina sections revealed a co-localization of both Rab27a and Ca(V)1.3 at the basolateral membrane of the RPE. Heterologously expressed Ca(V)1.3/β3/α2δ1 channels showed negatively shifted voltage-dependence and decreased current density of about 70% when co-expressed with Rab27a. However, co-localization analysis using α(5)β(1) integrin as a membrane marker revealed that Rab27a co-expression reduced the surface expression of Ca(V)1.3 only about 10%. Physical binding of heterologously expressed Rab27a with Ca(V)1.3 channels was shown by co-localization in immunocytochemistry as well as co-immunoprecipitation which was abolished after deletion of a MyRIP-homologous amino acid sequence at the II-III linker of the Ca(V)1.3 subunit. Rab27a over-expression in ARPE-19 cells positively shifted the voltage dependence, decreased current density of endogenous Ca(V)1.3 channels and reduced VEGF-A secretion. We show the first evidence of a direct functional modulation of an ion channel by Rab27a suggesting a new mechanism of Rab and ion channel interaction in the control of VEGF-A secretion in the RPE.

  9. Gain-of-function nature of Cav1.4 L-type calcium channels alters firing properties of mouse retinal ganglion cells

    PubMed Central

    Knoflach, Dagmar; Schicker, Klaus; Glösmann, Martin; Koschak, Alexandra

    2015-01-01

    Proper function of Cav1.4 L-type calcium channels is crucial for neurotransmitter release in the retina. Our understanding about how different levels of Cav1.4 channel activity affect retinal function is still limited. In the gain-of-function mouse model Cav1.4-IT we expected a reduction in the photoreceptor dynamic range but still transmission toward retinal ganglion cells. A fraction of Cav1.4-IT ganglion cells responded to light stimulation in multielectrode array recordings from whole-mounted retinas, but showed a significantly delayed response onset. Another significant number of cells showed higher activity in darkness. In addition to structural remodeling observed at the first retinal synapse of Cav1.4-IT mice the functional data suggested a loss of contrast enhancement, a fundamental feature of our visual system. In fact, Cav1.4-IT mouse retinas showed a decline in spatial response and changes in their contrast sensitivity profile. Photoreceptor degeneration was obvious from the nodular structure of cone axons and enlarged pedicles which partly moved toward the outer nuclear layer. Loss of photoreceptors was also expressed as reduced expression of proteins involved in chemical and electrical transmission, as such metabotropic glutamate receptor mGluR6 and the gap junction protein Connexin 36. Such gross changes in retinal structure and function could also explain the diminished visual performance of CSNB2 patients. The expression pattern of the plasma-membrane calcium ATPase 1 which participates in the maintenance of the intracellular calcium homeostasis in photoreceptors was changed in Cav1.4-IT mice. This might be part of a protection mechanism against increased calcium influx, as this is suggested for Cav1.4-IT channels. PMID:26274509

  10. CACNA1B (Cav2.2) Overexpression and Its Association with Clinicopathologic Characteristics and Unfavorable Prognosis in Non-Small Cell Lung Cancer

    PubMed Central

    Zhou, Xiaoyu; Wang, Wei; Zhang, Shu; Wang, Xudong; Tang, Zhiyuan; Gu, Jun; Li, Jun

    2017-01-01

    CACNA1B (Cav2.2) encodes an N-type voltage-gated calcium channel (VGCC) ubiquitously expressed in brain and peripheral nervous system that is important for regulating neuropathic pain. Because intracellular calcium concentration is a key player in cell proliferation and apoptosis, VGCCs are implicated in tumorigenesis. Recent studies have identified CACNA1B (Cav2.2) being overexpressed in prostate and breast cancer tissues when compared to adjacent normal tissues; however, its role in non-small cell lung cancer (NSCLC) has not been investigated. In this study, we determined the mRNA and protein expression of CACNA1B (Cav2.2) in NSCLC tumorous and adjacent nontumorous tissues by quantitative reverse transcription PCR (qRT-PCR) and tissue microarray immunohistochemistry analysis (TMA-IHC), respectively. CACNA1B (Cav2.2) protein expressions in tumorous tissues were correlated with NSCLC patients' clinical characteristics and overall survival. CACNA1B (Cav2.2) mRNA and protein expression levels were higher in NSCLC tumorous tissues than in nontumorous tissues. High CACNA1B (Cav2.2) protein expression was associated with higher TNM stages, and CACNA1B (Cav2.2) protein expression is an independent prognostic marker in NSCLC. Based on our results, we conclude that CACNA1B (Cav2.2) plays a role in NSCLC development and progression. Elucidating the underlying mechanism may help design novel treatment by specifically targeting the calcium regulation pathway for NSCLC, a devastating disease with increasing incidence and mortality in China. PMID:28127114

  11. Orai1 and TRPC1 Proteins Co-localize with CaV1.2 Channels to Form a Signal Complex in Vascular Smooth Muscle Cells.

    PubMed

    Ávila-Medina, Javier; Calderón-Sánchez, Eva; González-Rodríguez, Patricia; Monje-Quiroga, Francisco; Rosado, Juan Antonio; Castellano, Antonio; Ordóñez, Antonio; Smani, Tarik

    2016-09-30

    Voltage-dependent CaV1.2 L-type Ca(2+) channels (LTCC) are the main route for calcium entry in vascular smooth muscle cells (VSMC). Several studies have also determined the relevant role of store-operated Ca(2+) channels (SOCC) in vascular tone regulation. Nevertheless, the role of Orai1- and TRPC1-dependent SOCC in vascular tone regulation and their possible interaction with CaV1.2 are still unknown. The current study sought to characterize the co-activation of SOCC and LTCC upon stimulation by agonists, and to determine the possible crosstalk between Orai1, TRPC1, and CaV1.2. Aorta rings and isolated VSMC obtained from wild type or smooth muscle-selective conditional CaV1.2 knock-out (CaV1.2(KO)) mice were used to study vascular contractility, intracellular Ca(2+) mobilization, and distribution of ion channels. We found that serotonin (5-HT) or store depletion with thapsigargin (TG) enhanced intracellular free Ca(2+) concentration ([Ca(2+)]i) and stimulated aorta contraction. These responses were sensitive to LTCC and SOCC inhibitors. Also, 5-HT- and TG-induced responses were significantly attenuated in CaV1.2(KO) mice. Furthermore, hyperpolarization induced with cromakalim or valinomycin significantly reduced both 5-HT and TG responses, whereas these responses were enhanced with LTCC agonist Bay-K-8644. Interestingly, in situ proximity ligation assay revealed that CaV1.2 interacts with Orai1 and TRPC1 in untreated VSMC. These interactions enhanced significantly after stimulation of cells with 5-HT and TG. Therefore, these data indicate for the first time a functional interaction between Orai1, TRPC1, and CaV1.2 channels in VSMC, confirming that upon agonist stimulation, vessel contraction involves Ca(2+) entry due to co-activation of Orai1- and TRPC1-dependent SOCC and LTCC.

  12. Impaired Long-term Potentiation and Enhanced Neuronal Excitability in the Amygdala of CaV1.3 Knockout Mice

    PubMed Central

    McKinney, Brandon C.; Sze, Wilson; Lee, Benjamin; Murphy, Geoffrey G.

    2009-01-01

    Previously, we demonstrated that mice in which the gene for the L-type voltage-gated calcium channel CaV1.3 is deleted (CaV1.3 knockout mice) exhibit an impaired ability to consolidate contextually-conditioned fear. Given that this form of Pavlovian fear conditioning is critically dependent on the basolateral complex of the amygdala (BLA), we were interested in the mechanisms by which CaV1.3 contributes to BLA neurophysiology. In the present study, we used in vitro amygdala slices prepared from CaV1.3 knockout mice and wild-type littermates to explore the role of CaV1.3 in long-term potentiation (LTP) and intrinsic neuronal excitability in the BLA. We found that LTP in the lateral nucleus (LA) of the BLA, induced by high-frequency stimulation of the external capsule, was significantly reduced in CaV1.3 knockout mice. Additionally, we found that BLA principal neurons from CaV1.3 knockout mice were hyperexcitable, exhibiting significant increases in firing rates and decreased interspike intervals in response to prolonged somatic depolarization. This aberrant increase in neuronal excitability appears to be at least in part due to a concomitant reduction in the slow component of the post-burst afterhyperpolarization. Together, these results demonstrate altered neuronal function in the BLA of CaV1.3 knockout mice which may account for the impaired ability of these mice to consolidate contextually-conditioned fear. PMID:19595780

  13. Spleen tyrosine kinase contributes to acute renal allograft rejection in the rat

    PubMed Central

    Ramessur Chandran, Sharmila; Tesch, Greg H; Han, Yingjie; Woodman, Naomi; Mulley, William R; Kanellis, John; Blease, Kate; Ma, Frank Y; Nikolic-Paterson, David J

    2015-01-01

    Kidney allografts induce strong T-cell and antibody responses which mediate acute rejection. Spleen tyrosine kinase (Syk) is expressed by most leucocytes, except mature T cells, and is involved in intracellular signalling following activation of the Fcγ-receptor, B-cell receptor and some integrins. A role for Syk signalling has been established in antibody-dependent native kidney disease, but little is known of Syk in acute renal allograft rejection. Sprague–Dawley rats underwent bilateral nephrectomy and received an orthotopic Wistar renal allograft. Recipient rats were treated with a Syk inhibitor (CC0482417, 30 mg/kg/bid), or vehicle, from 1 h before surgery until being killed 5 days later. Vehicle-treated recipients developed severe allograft failure with marked histologic damage in association with dense leucocyte infiltration (T cells, macrophages, neutrophils and NK cells) and deposition of IgM, IgG and C3. Immunostaining identified Syk expression by many infiltrating leucocytes. CC0482417 treatment significantly improved allograft function and reduced histologic damage, although allograft injury was still clearly evident. CC0482417 failed to prevent T-cell infiltration and activation within the allograft. However, CC0482417 significantly attenuated acute tubular necrosis, infiltration of macrophages and neutrophils and thrombosis of peritubular capillaries. In conclusion, this study identifies a role for Syk in acute renal allograft rejection. Syk inhibition may be a useful addition to T-cell-based immunotherapy in renal transplantation. PMID:25529862

  14. Morphometric and physical investigations of segmental cortical bone autografts and allografts in canine ulnar defects.

    PubMed

    Delloye, C; Verhelpen, M; d'Hemricourt, J; Govaerts, B; Bourgois, R

    1992-09-01

    Cortical bone grafts were implanted for six months in mature dogs using an osteoperiosteal 3-cm defect in the ulna to evaluate their respective morphometric and physical values compared with autografts. The bone-grafting material included fresh auto- and allografts, frozen and thimerosal preserved allografts, and partially demineralized bone allografts. The grafts were evaluated by roentgenograms, microradiograms, photon absorptiometry, porosity, fluorescence labeling measurements, and torsional loading at failure. Autografts achieved a better union score than the allografts, but intracortical bone porosity, percentage of cumulative new bone, and mineral apposition rate were not variables with statistical significance. Lamellar bone was found earlier and in greater quantity in autografts. Within the graft, new bone was deposited at a slower rate than in the recipient bone. Autografts showed less peripheral resorption and a greater torsional resistance than allografts. Photon absorptiometry demonstrated that nondemineralized allografts underwent a substantial loss of peripheral bone. This marked reduction in the outer diameter of the graft had more influence on torsional resistance than did the intracortical porosity of the graft. Demineralized allografts were osteoinductive in only 28% of the cases and appeared to respond in an all-or-nothing pattern. Frozen and thimerosal preserved allografts were the most acceptable substitutes to autografts.

  15. Cholinergic control of firing pattern and neurotransmission in rat neostriatal projection neurons: role of CaV2.1 and CaV2.2 Ca2+ channels.

    PubMed

    Perez-Rosello, Tamara; Figueroa, Alejandra; Salgado, Humberto; Vilchis, Carmen; Tecuapetla, Fatuel; Guzman, Jaime N; Galarraga, Elvira; Bargas, Jose

    2005-05-01

    Besides a reduction of L-type Ca2+-currents (Ca(V)1), muscarine and the peptidic M1-selective agonist, MT-1, reduced currents through Ca(V)2.1 (P/Q) and Ca(V)2.2 (N) Ca2+ channel types. This modulation was strongly blocked by the peptide MT-7, a specific muscarinic M1-type receptor antagonist but not significantly reduced by the peptide MT-3, a specific muscarinic M4-type receptor antagonist. Accordingly, MT-7, but not MT-3, blocked a muscarinic reduction of the afterhyperpolarizing potential (AHP) and decreased the GABAergic inhibitory postsynaptic currents (IPSCs) produced by axon collaterals that interconnect spiny neurons. Both these functions are known to be dependent on P/Q and N types Ca2+ channels. The action on the AHP had an important effect in increasing firing frequency. The action on the IPSCs was shown to be caused presynaptically as it coursed with an increase in the paired-pulse ratio. These results show: first, that muscarinic M1-type receptor activation is the main cholinergic mechanism that modulates Ca2+ entry through voltage-dependent Ca2+ channels in spiny neurons. Second, this muscarinic modulation produces a postsynaptic facilitation of discharge together with a presynaptic inhibition of the GABAergic control mediated by axon collaterals. Together, both effects would tend to recruit more spiny neurons for the same task.

  16. Limited Efficacy of α-Conopeptides, Vc1.1 and RgIA, To Inhibit Sensory Neuron CaV Current1,2,3

    PubMed Central

    Wright, Andrew B.; Norimatsu, Yohei; McIntosh, J. Michael; Elmslie, Keith S.

    2015-01-01

    Abstract Chronic pain is very difficult to treat. Thus, novel analgesics are a critical area of research. Strong preclinical evidence supports the analgesic effects of α-conopeptides, Vc1.1 and RgIA, which block α9α10 nicotinic acetylcholine receptors (nAChRs). However, the analgesic mechanism is controversial. Some evidence supports the block of α9α10 nAChRs as an analgesic mechanism, while other evidence supports the inhibition of N-type CaV (CaV2.2) current via activation of GABAB receptors. Here, we reassess the effect of Vc1.1 and RgIA on CaV current in rat sensory neurons. Unlike the previous findings, we found highly variable effects among individual sensory neurons, but on average only minimal inhibition induced by Vc1.1, and no significant effect on the current by RgIA. We also investigated the potential involvement of GABAB receptors in the Vc1.1-induced inhibition, and found no correlation between the size of CaV current inhibition induced by baclofen (GABAB agonist) versus that induced by Vc1.1. Thus, GABAB receptors are unlikely to mediate the Vc1.1-induced CaV current inhibition. Based on the present findings, CaV current inhibition in dorsal root ganglia is unlikely to be the predominant mechanism by which either Vc1.1 or RgIA induce analgesia. PMID:26078999

  17. Divergent biophysical properties, gating mechanisms, and possible functions of the two skeletal muscle CaV1.1 calcium channel splice variants

    PubMed Central

    Tuluc, Petronel; Flucher, Bernhard E.

    2014-01-01

    Voltage-gated calcium channels are multi-subunit protein complexes that specifically allow calcium ions to enter the cell in response to membrane depolarization. But, for many years it seemed that the skeletal muscle calcium channel CaV1.1 is the exception. The classical splice variant CaV1.1a activates slowly, has a very small current amplitude and poor voltage sensitivity. In fact adult muscle fibers work perfectly well even in the absence of calcium influx. Recently a new splice variant of the skeletal muscle calcium channel CaV1.1e has been characterized. The lack of the 19 amino acid exon 29 in this splice variant results in a rapidly activating calcium channel with high current amplitude and good voltage sensitivity. CaV1.1e is the dominant channel in embryonic muscle, where the expression of this high calcium-conducting CaV1.1 isoform readily explains developmental processes depending on L-type calcium currents. Moreover, the availability of these two structurally similar but functionally distinct channel variants facilitates the analysis of the molecular mechanisms underlying the unique current properties of the classical CaV1.1a channel. PMID:22057633

  18. Regulation of Postsynaptic Stability by the L-type Calcium Channel CaV1.3 and its Interaction with PDZ Proteins

    PubMed Central

    Stanika, Ruslan I.; Flucher, Bernhard E.; Obermair, Gerald J.

    2015-01-01

    Alterations in dendritic spine morphology and postsynaptic structure are a hallmark of neurological disorders. Particularly spine pruning of striatal medium spiny neurons and aberrant rewiring of corticostriatal synapses have been associated with the pathology of Parkinson’s disease and L-DOPA induced dyskinesia, respectively. Owing to its low activation threshold the neuronal L-type calcium channel CaV1.3 is particularly critical in the control of neuronal excitability and thus in the calcium-dependent regulation of neuronal functions. CaV1.3 channels are located in dendritic spines and contain a C-terminal class 1 PDZ domain-binding sequence. Until today the postsynaptic PDZ domain proteins shank, densin-180, and erbin have been shown to interact with CaV1.3 channels and to modulate their current properties. Interestingly experimental evidence suggests an involvement of all three PDZ proteins as well as CaV1.3 itself in regulating dendritic and postsynaptic morphology. Here we briefly review the importance of CaV1.3 and its proposed interactions with PDZ proteins for the stability of dendritic spines. With a special focus on the pathology associated with Parkinson’s disease, we discuss the hypothesis that CaV1.3 L-type calcium channels may be critical modulators of dendritic spine stability. PMID:25966696

  19. T-type calcium channel Cav3.2 deficient mice show elevated anxiety, impaired memory and reduced sensitivity to psychostimulants

    PubMed Central

    Gangarossa, Giuseppe; Laffray, Sophie; Bourinet, Emmanuel; Valjent, Emmanuel

    2014-01-01

    The fine-tuning of neuronal excitability relies on a tight control of Ca2+ homeostasis. The low voltage-activated (LVA) T-type calcium channels (Cav3.1, Cav3.2 and Cav3.3 isoforms) play a critical role in regulating these processes. Despite their wide expression throughout the central nervous system, the implication of T-type Cav3.2 isoform in brain functions is still poorly characterized. Here, we investigate the effect of genetic ablation of this isoform in affective disorders, including anxiety, cognitive functions as well as sensitivity to drugs of abuse. Using a wide range of behavioral assays we show that genetic ablation of the cacna1h gene results in an anxiety-like phenotype, whereas novelty-induced locomotor activity is unaffected. Deletion of the T-type channel Cav3.2 also triggers impairment of hippocampus-dependent recognition memories. Acute and sensitized hyperlocomotion induced by d-amphetamine and cocaine are dramatically reduced in T-type Cav3.2 deficient mice. In addition, the administration of the T-type blocker TTA-A2 prevented the expression of locomotor sensitization observed in wildtype mice. In conclusion, our data reveal that physiological activity of this specific Ca2+ channel is required for affective and cognitive behaviors. Moreover, our work highlights the interest of T-type channel blockers as therapeutic strategies to reverse drug-associated alterations. PMID:24672455

  20. Endocrine function after immunosuppression of pancreatic allograft by ionizing irradiation in the primate

    SciTech Connect

    Du Toit, D.F.; Heydenrych, J.J.; Smit, B.; Louw, G.; Zuurmond, T.; Laker, L.; Els, D.; Weideman, A.; Wolfe-Coote, S.; Du Toit, L.B.

    1986-05-01

    The object of this preliminary study was to evaluate the endocrine function after heterotopic intraperitoneal segmental pancreatic allotransplantation with unligated duct in irradiated, totally pancreatectomized primates. All allograft recipients received, pre- and peroperative donor-specific blood transfusions and peroperative external irradiation from a linear accelerator; 200 rads was administered weekly and increased to a total dose of 1,500 rads. Pancreatic transplantation was performed between 2 and 6 weeks after completion of irradiation and preoperative blood transfusions. As previously reported, only minimal pancreatic allograft survival was achieved following preoperative irradiation. One recipient remained normoglycaemic for greater than 100 days after transplantation, the longest surviving pancreatic allograft recipient reported from this laboratory. Intravenous glucose tolerance test results in this recipient revealed normoglycaemia, reduced K-value, hypoinsulinaemia, normal glucagon response, reduced C-peptide values, and moderate glucose intolerance. Aortography and electron-microscopic examination of allograft biopsy tissue confirmed the presence of a functioning allograft.

  1. Impaired Endothelial Nitric Oxide Synthase Homodimer Formation Triggers Development of Transplant Vasculopathy - Insights from a Murine Aortic Transplantation Model

    PubMed Central

    Oberhuber, Rupert; Riede, Gregor; Cardini, Benno; Bernhard, David; Messner, Barbara; Watschinger, Katrin; Steger, Christina; Brandacher, Gerald; Pratschke, Johann; Golderer, Georg; Werner, Ernst R.; Maglione, Manuel

    2016-01-01

    Transplant vasculopathy (TV) represents a major obstacle to long-term graft survival and correlates with severity of ischemia reperfusion injury (IRI). Donor administration of the nitric oxide synthases (NOS) co-factor tetrahydrobiopterin has been shown to prevent IRI. Herein, we analysed whether tetrahydrobiopterin is also involved in TV development. Using a fully allogeneic mismatched (BALB/c to C57BL/6) murine aortic transplantation model grafts subjected to long cold ischemia time developed severe TV with intimal hyperplasia (α-smooth muscle actin positive cells in the neointima) and endothelial activation (increased P-selectin expression). Donor pretreatment with tetrahydrobiopterin significantly minimised these changes resulting in only marginal TV development. Severe TV observed in the non-treated group was associated with increased protein oxidation and increased occurrence of endothelial NOS monomers in the aortic grafts already during graft procurement. Tetrahydrobiopterin supplementation of the donor prevented all these early oxidative changes in the graft. Non-treated allogeneic grafts without cold ischemia time and syngeneic grafts did not develop any TV. We identified early protein oxidation and impaired endothelial NOS homodimer formation as plausible mechanistic explanation for the crucial role of IRI in triggering TV in transplanted aortic grafts. Therefore, targeting endothelial NOS in the donor represents a promising strategy to minimise TV. PMID:27883078

  2. Vasculopathy associated hyperangiotensinemia mobilizes hematopoietic stem cells/progenitors through endothelial AT2R and cytoskeletal dysregulation

    PubMed Central

    Chang, Kyung Hee; Nayak, Ramesh C.; Roy, Swarnava; Perumbeti, Ajay; Wellendorf, Ashley M.; Bezold, Katie Y.; Pirman, Megan; Hill, Sarah E.; Starnes, Joseph; Loberg, Anastacia; Zhou, Xuan; Inagami, Tadashi; Zheng, Yi; Malik, Punam; Cancelas, Jose A.

    2014-01-01

    Patients in organ failure of vascular origin have increased circulating hematopoietic stem cells and progenitors (HSC/P). Plasma levels of angiotensin II (Ang-II), are commonly increased in vasculopathies. Hyperangiotensinemia results in activation of a very distinct Ang-II receptor set, Rho-family GTPase members, and actin in bone marrow endothelial cells (BMEC) and HSC/P, which results in decreased membrane integrin activation in both BMEC and HSC/P, and in HSC/P de-adhesion and mobilization. The Ang-II effect can be reversed pharmacologically and genetically by inhibiting Ang-II production or signaling through BMEC AT2R, HSCP AT1R/AT2R or HSC/P RhoA, but not by interfering with other vascular tone mediators. Hyperangiotensinemia and high counts of circulating HSC/P seen in sickle cell disease (SCD) as a result of vascular damage, is significantly decreased by Ang-II inhibitors. Our data define for the first time the role of Ang-II HSC/P traffic regulation and redefine the hematopoietic consequences of anti-angiotensin therapy in SCD. PMID:25574809

  3. Reversal of diabetic vasculopathy in a rat model of type 1 diabetes by opiorphin-related peptides

    PubMed Central

    Calenda, Giulia; Tong, Yuehong; Kanika, Nirmala D.; Tar, Moses T.; Suadicani, Sylvia O.; Zhang, Xinhua; Melman, Arnold; Rougeot, Catherine

    2011-01-01

    Diabetes results in a myriad of vascular complications, often referred to as diabetic vasculopathy, which encompasses both microvascular [erectile dysfunction (ED), retinopathy, neuropathy, and nephropathy] and macrovascular complications (hypertension, coronary heart disease, and myocardial infarction). In diabetic animals and patients with ED, there is decreased opiorphin or opiorphin-related gene expression in corporal tissue. Both opiorphin and the rat homologous peptide sialorphin are found circulating in the plasma. In the present study, we investigated if diabetes induced changes in plasma sialorphin levels and if changes in these levels could modulate the biochemistry and physiology of vascular smooth muscle. We show that circulating sialorphin levels are reduced in a rat model of type I diabetes. Intracorporal injection of plasmids expressing sialorphin into diabetic rats restores sialorphin levels to those seen in the blood of nondiabetic animals and results in both improved erectile function and blood pressure. Sialorphin modulated the ability of C-type natriuretic peptide to relax both corporal and aortic smooth muscle strips and of bradykinin to regulate intracellular calcium levels in both corporal and aortic smooth muscle cells. We have previously shown that expression of genes encoding opiorphins is increased when erectile function is improved. Our findings thus suggest that by affecting circulating levels of opiorphin-related peptides, proper erectile function is not only an indicator but also a modulator of overall vascular health of a man. PMID:21784987

  4. Reversal of diabetic vasculopathy in a rat model of type 1 diabetes by opiorphin-related peptides.

    PubMed

    Calenda, Giulia; Tong, Yuehong; Kanika, Nirmala D; Tar, Moses T; Suadicani, Sylvia O; Zhang, Xinhua; Melman, Arnold; Rougeot, Catherine; Davies, Kelvin P

    2011-10-01

    Diabetes results in a myriad of vascular complications, often referred to as diabetic vasculopathy, which encompasses both microvascular [erectile dysfunction (ED), retinopathy, neuropathy, and nephropathy] and macrovascular complications (hypertension, coronary heart disease, and myocardial infarction). In diabetic animals and patients with ED, there is decreased opiorphin or opiorphin-related gene expression in corporal tissue. Both opiorphin and the rat homologous peptide sialorphin are found circulating in the plasma. In the present study, we investigated if diabetes induced changes in plasma sialorphin levels and if changes in these levels could modulate the biochemistry and physiology of vascular smooth muscle. We show that circulating sialorphin levels are reduced in a rat model of type I diabetes. Intracorporal injection of plasmids expressing sialorphin into diabetic rats restores sialorphin levels to those seen in the blood of nondiabetic animals and results in both improved erectile function and blood pressure. Sialorphin modulated the ability of C-type natriuretic peptide to relax both corporal and aortic smooth muscle strips and of bradykinin to regulate intracellular calcium levels in both corporal and aortic smooth muscle cells. We have previously shown that expression of genes encoding opiorphins is increased when erectile function is improved. Our findings thus suggest that by affecting circulating levels of opiorphin-related peptides, proper erectile function is not only an indicator but also a modulator of overall vascular health of a man.

  5. Dietary ω-3 fatty acids protect against vasculopathy in a transgenic mouse model of sickle cell disease.

    PubMed

    Kalish, Brian T; Matte, Alessandro; Andolfo, Immacolata; Iolascon, Achille; Weinberg, Olga; Ghigo, Alessandra; Cimino, James; Siciliano, Angela; Hirsch, Emilio; Federti, Enrica; Puder, Mark; Brugnara, Carlo; De Franceschi, Lucia

    2015-07-01

    The anemia of sickle cell disease is associated with a severe inflammatory vasculopathy and endothelial dysfunction, which leads to painful and life-threatening clinical complications. Growing evidence supports the anti-inflammatory properties of ω-3 fatty acids in clinical models of endothelial dysfunction. Promising but limited studies show potential therapeutic effects of ω-3 fatty acid supplementation in sickle cell disease. Here, we treated humanized healthy and sickle cell mice for 6 weeks with ω-3 fatty acid diet (fish-oil diet). We found that a ω-3 fatty acid diet: (i) normalizes red cell membrane ω-6/ω-3 ratio; (ii) reduces neutrophil count; (iii) decreases endothelial activation by targeting endothelin-1 and (iv) improves left ventricular outflow tract dimensions. In a hypoxia-reoxygenation model of acute vaso-occlusive crisis, a ω-3 fatty acid diet reduced systemic and local inflammation and protected against sickle cell-related end-organ injury. Using isolated aortas from sickle cell mice exposed to hypoxia-reoxygenation, we demonstrated a direct impact of a ω-3 fatty acid diet on vascular activation, inflammation, and anti-oxidant systems. Our data provide the rationale for ω-3 dietary supplementation as a therapeutic intervention to reduce vascular dysfunction in sickle cell disease.

  6. Dietary ω-3 fatty acids protect against vasculopathy in a transgenic mouse model of sickle cell disease

    PubMed Central

    Kalish, Brian T.; Matte, Alessandro; Andolfo, Immacolata; Iolascon, Achille; Weinberg, Olga; Ghigo, Alessandra; Cimino, James; Siciliano, Angela; Hirsch, Emilio; Federti, Enrica; Puder, Mark; Brugnara, Carlo; De Franceschi, Lucia

    2015-01-01

    The anemia of sickle cell disease is associated with a severe inflammatory vasculopathy and endothelial dysfunction, which leads to painful and life-threatening clinical complications. Growing evidence supports the anti-inflammatory properties of ω-3 fatty acids in clinical models of endothelial dysfunction. Promising but limited studies show potential therapeutic effects of ω-3 fatty acid supplementation in sickle cell disease. Here, we treated humanized healthy and sickle cell mice for 6 weeks with ω-3 fatty acid diet (fish-oil diet). We found that a ω-3 fatty acid diet: (i) normalizes red cell membrane ω-6/ω-3 ratio; (ii) reduces neutrophil count; (iii) decreases endothelial activation by targeting endothelin-1 and (iv) improves left ventricular outflow tract dimensions. In a hypoxia-reoxygenation model of acute vaso-occlusive crisis, a ω-3 fatty acid diet reduced systemic and local inflammation and protected against sickle cell-related end-organ injury. Using isolated aortas from sickle cell mice exposed to hypoxia-reoxygenation, we demonstrated a direct impact of a ω-3 fatty acid diet on vascular activation, inflammation, and anti-oxidant systems. Our data provide the rationale for ω-3 dietary supplementation as a therapeutic intervention to reduce vascular dysfunction in sickle cell disease. PMID:25934765

  7. Vasculopathy-associated hyperangiotensinemia mobilizes haematopoietic stem cells/progenitors through endothelial AT₂R and cytoskeletal dysregulation.

    PubMed

    Chang, Kyung Hee; Nayak, Ramesh C; Roy, Swarnava; Perumbeti, Ajay; Wellendorf, Ashley M; Bezold, Katie Y; Pirman, Megan; Hill, Sarah E; Starnes, Joseph; Loberg, Anastacia; Zhou, Xuan; Inagami, Tadashi; Zheng, Yi; Malik, Punam; Cancelas, Jose A

    2015-01-09

    Patients with organ failure of vascular origin have increased circulating haematopoietic stem cells and progenitors (HSC/P). Plasma levels of angiotensin II (Ang-II), are commonly increased in vasculopathies. Hyperangiotensinemia results in activation of a very distinct Ang-II receptor set, Rho family GTPase members, and actin in bone marrow endothelial cells (BMEC) and HSC/P, which results in decreased membrane integrin activation in both BMEC and HSC/P, and in HSC/P de-adhesion and mobilization. The Ang-II effect can be reversed pharmacologically and genetically by inhibiting Ang-II production or signalling through BMEC AT2R, HSCP Ang-II receptor type 1 (AT1R)/AT2R or HSC/P RhoA, but not by interfering with other vascular tone mediators. Hyperangiotensinemia and high counts of circulating HSC/P seen in sickle cell disease (SCD) as a result of vascular damage, is significantly decreased by Ang-II inhibitors. Our data define for the first time the role of Ang-II HSC/P traffic regulation and redefine the haematopoietic consequences of anti-angiotensin therapy in SCD.

  8. Cutaneous and renal glomerular vasculopathy as a cause of acute kidney injury in dogs in the UK

    PubMed Central

    Hawkins, I.; Robin, C.; Newton, R. J.; Jepson, R.; Stanzani, G.; McMahon, L. A.; Pesavento, P.; Carr, T.; Cogan, T.; Couto, C. G.; Cianciolo, R.; Walker, D. J.

    2015-01-01

    To describe the signalment, clinicopathological findings and outcome in dogs presenting with acute kidney injury (AKI) and skin lesions between November 2012 and March 2014, in whom cutaneous and renal glomerular vasculopathy (CRGV) was suspected and renal thrombotic microangiopathy (TMA) was histopathologically confirmed. The medical records of dogs with skin lesions and AKI, with histopathologically confirmed renal TMA, were retrospectively reviewed. Thirty dogs from across the UK were identified with clinicopathological findings compatible with CRGV. These findings included the following: skin lesions, predominantly affecting the distal extremities; AKI; and variably, anaemia, thrombocytopaenia and hyperbilirubinaemia. Known causes of AKI were excluded. The major renal histopathogical finding was TMA. All thirty dogs died or were euthanised. Shiga toxin was not identified in the kidneys of affected dogs. Escherichia coli genes encoding shiga toxin were not identified in faeces from affected dogs. CRGV has previously been reported in greyhounds in the USA, a greyhound in the UK, without renal involvement, and a Great Dane in Germany. This is the first report of a series of non-greyhound dogs with CRGV and AKI in the UK. CRGV is a disease of unknown aetiology carrying a poor prognosis when azotaemia develops. PMID:25802439

  9. Results of 32 Allograft-prosthesis Composite Reconstructions of the Proximal Femur

    PubMed Central

    Larousserie, Frédérique; Thévenin, Fabrice; Piperno-Neumann, Sophie; Anract, Philippe

    2009-01-01

    The use of allograft-prosthesis composites for reconstruction after bone tumor resection at the proximal femur has generated considerable interest since the mid1980s on the basis that their use would improve function and survival, and restore bone stock. Although functional improvement has been documented, it is unknown whether these composites survive long periods and whether they restore bone stock. We therefore determined long-term allograft-prosthesis composite survival, identified major complications that led to revision, and determined whether allograft bone stock could be spared at the time of revision. We also compared the radiographic appearance of allografts sterilized by gamma radiation and fresh-frozen allografts. We retrospectively reviewed 32 patients with bone malignancy in the proximal femur who underwent reconstruction with a cemented allograft-prosthesis composite. The allograft-prosthesis composite was a primary reconstruction for 23 patients and a revision procedure for nine. The minimum followup was 2 months (median, 68 months; range, 2–232 months). The cumulative incidence of revision for any reason was 14% at 5 years (95% confidence interval, 1%–28%) and 19% at 10 years (95% confidence interval, 3%–34%). Nine patients (28%) had revision of the reconstruction during followup; four of these patients had revision surgery for infection. Allografts sterilized by gamma radiation showed worse resorption than fresh-frozen allografts. Based on reported results, allograft-composite prostheses do not appear to improve survival compared with megaprostheses. Level of Evidence: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence. PMID:19851817

  10. Modulation of Cav3.2 T-type calcium channel permeability by asparagine-linked glycosylation.

    PubMed

    Ondacova, Katarina; Karmazinova, Maria; Lazniewska, Joanna; Weiss, Norbert; Lacinova, Lubica

    2016-01-01

    Low-voltage-gated T-type calcium channels are expressed throughout the nervous system where they play an essential role in shaping neuronal excitability. Defects in T-type channel expression have been linked to various neuronal disorders including neuropathic pain and epilepsy. Currently, little is known about the cellular mechanisms controlling the expression and function of T-type channels. Asparagine-linked glycosylation has recently emerged as an essential signaling pathway by which the cellular environment can control expression of T-type channels. However, the role of N-glycans in the conducting function of T-type channels remains elusive. In the present study, we used human Cav3.2 glycosylation-deficient channels to assess the role of N-glycosylation on the gating of the channel. Patch-clamp recordings of gating currents revealed that N-glycans attached to hCav3.2 channels have a minimal effect on the functioning of the channel voltage-sensor. In contrast, N-glycosylation on specific asparagine residues may have an essential role in the conducting function of the channel by enhancing the channel permeability and / or the pore opening of the channel. Our data suggest that modulation of N-linked glycosylation of hCav3.2 channels may play an important physiological role, and could also support the alteration of T-type currents observed in disease states.

  11. CaV2.1 voltage activated calcium channels and synaptic transmission in familial hemiplegic migraine pathogenesis.

    PubMed

    Uchitel, Osvaldo D; Inchauspe, Carlota González; Urbano, Francisco J; Di Guilmi, Mariano N

    2012-01-01

    Studies on the genetic forms of epilepsy, chronic pain, and migraine caused by mutations in ion channels have given crucial insights into the molecular mechanisms, pathogenesis, and therapeutic approaches to complex neurological disorders. In this review we focus on the role of mutated CaV2.1 (i.e., P/Q-type) voltage-activated Ca2+ channels, and on the ultimate consequences that mutations causing familial hemiplegic migraine type-1 (FHM1) have in neurotransmitter release. Transgenic mice harboring the human pathogenic FHM1 mutation R192Q or S218L (KI) have been used as models to study neurotransmission at several central and peripheral synapses. FHM1 KI mice are a powerful tool to explore presynaptic regulation associated with expression of CaV2.1 channels. Mutated CaV2.1 channels activate at more hyperpolarizing potentials and lead to a gain-of-function in synaptic transmission. This gain-of-function might underlie alterations in the excitatory/ inhibitory balance of synaptic transmission, favoring a persistent state of hyperexcitability in cortical neurons that would increase the susceptibility for cortical spreading depression (CSD), a mechanism believed to initiate the attacks of migraine with aura.

  12. STAC3 stably interacts through its C1 domain with CaV1.1 in skeletal muscle triads

    PubMed Central

    Campiglio, Marta; Flucher, Bernhard E.

    2017-01-01

    The adaptor protein STAC3 is essential for skeletal muscle excitation-contraction (EC) coupling and a mutation in the STAC3 gene has been linked to a severe muscle disease, Native American myopathy (NAM). However the function of STAC3, its interaction partner, and the mode of interaction within the EC-coupling complex remained elusive. Here we demonstrate that STAC3 forms a stable interaction with the voltage-sensor of EC-coupling, CaV1.1, and that this interaction depends on a hitherto unidentified protein-protein binding pocket in the C1 domain of STAC3. While the NAM mutation does not affect the stability of the STAC3-CaV1.1 interaction, mutation of two crucial residues in the C1 binding pocket increases the turnover of STAC3 in skeletal muscle triads. Thus, the C1 domain of STAC3 is responsible for its stable incorporation into the CaV1.1 complex, whereas the SH3 domain containing the NAM mutation site may be involved in low-affinity functional interactions in EC-coupling. PMID:28112192

  13. Meniscal Allograft Interposition Combined with Proximal Row Carpectomy.

    PubMed

    Steiner, Murphy M; Willsey, Matthew R; Werner, Frederick W; Harley, Brian J; Klein, Shay; Setter, Kevin J

    2017-02-01

    Background Proximal row carpectomy (PRC) is contraindicated in wrists with preexisting arthritis of the proximal capitate or radiolunate fossa. Patients with these conditions frequently pursue wrist arthrodesis with its associated functional limitations. Questions/Purposes The purpose of this study was to evaluate the results of using lateral meniscal allograft interposition (LMAI), in combination with PRC, in patients with symptomatic wrist arthritis. The primary question is whether this allograft will allow wrist function comparable to that in patients having only a PRC. A secondary question was to determine the short-term longevity of the allograft. Patients/Method Between 2006 and 2012, nine wrists underwent PRC with LMAI. Patient demographics and rates of complication or graft failure were determined. During independent clinical exams, functional outcomes were reviewed, patients completed a Disabilities of the Arm, Shoulder, and Hand (DASH) scores, and radiographs were taken. Results Four patients met the inclusion criteria, having clinical follow-up at an average of 4.2 years. DASH scores at the time of follow-up ranged from 9 to 33, with an average of 24. Average radiocapitate joint space in the first postoperative radiograph was 2.8 mm compared with 1.8 mm at the time of final follow-up. No wrists went on to arthrodesis. Conclusion Early outcomes of PRC with LMAI are comparable to those results found in the literature of PRC alone. LMAI with PRC may be a valid short-term option as a motion-preserving procedure in those patients contraindicated to having a PRC alone. Level of Evidence Level IV.

  14. Autoantibodies to Vimentin Cause Accelerated Rejection of Cardiac Allografts

    PubMed Central

    Mahesh, Balakrishnan; Leong, Hon-Sing; McCormack, Ann; Sarathchandra, Padmini; Holder, Angela; Rose, Marlene L.

    2007-01-01

    Autoimmune responses to vimentin occur after solid organ transplantation, but their pathogenic effects are unclear. The aim of these studies was to investigate the effects of vimentin preimmunization on allogeneic and isografted hearts in a murine transplant model. Immunization of C57BL/6 mice with murine vimentin in complete Freund’s adjuvant resulted in anti-vimentin antibodies and vimentin-reactive Th-1 cells. Transplantation of 129/sv hearts into vimentin-immunized C57BL/6 recipients resulted in accelerated rejection (8.4 ± 1.5 days; n = 18), compared with hen egg lysozyme-immunized C57BL/6 (13.3 ± 2.2 days; n = 10; P < 0.0001, log-rank test). In contrast, isografts continued to beat beyond 90 days. Immunohistochemical analysis of allografts from vimentin/complete Freund’s adjuvant mice demonstrated increased numbers of T cells and enhanced microvascular deposition of C3d, CD41, and P-selectin compared with controls. Antibodies were necessary for accelerated rejection, shown by the fact that vimentin-immunized B-cell-deficient IgH6 mice did not show accelerated rejection of 129/sv allografts, but rejection was restored by adoptive transfer of serum containing anti-vimentin antibodies. Eluates from donor hearts placed in vimentin/complete Freund’s adjuvant recipients contained anti-vimentin antibodies, shown by Western blotting. Confocal imaging of rejected hearts demonstrated presence of vimentin and C3d on apoptosed leukocytes, endothelial cells, and platelet/leukocyte conjugates. These results demonstrate that autoantibodies to vimentin, in conjunction with the alloimmune response, have a pathogenic role in allograft rejection. PMID:17392180

  15. Urine Metabolite Profiles Predictive of Human Kidney Allograft Status.

    PubMed

    Suhre, Karsten; Schwartz, Joseph E; Sharma, Vijay K; Chen, Qiuying; Lee, John R; Muthukumar, Thangamani; Dadhania, Darshana M; Ding, Ruchuang; Ikle, David N; Bridges, Nancy D; Williams, Nikki M; Kastenmüller, Gabi; Karoly, Edward D; Mohney, Robert P; Abecassis, Michael; Friedewald, John; Knechtle, Stuart J; Becker, Yolanda T; Samstein, Benjamin; Shaked, Abraham; Gross, Steven S; Suthanthiran, Manikkam

    2016-02-01

    Noninvasive diagnosis and prognostication of acute cellular rejection in the kidney allograft may help realize the full benefits of kidney transplantation. To investigate whether urine metabolites predict kidney allograft status, we determined levels of 749 metabolites in 1516 urine samples from 241 kidney graft recipients enrolled in the prospective multicenter Clinical Trials in Organ Transplantation-04 study. A metabolite signature of the ratio of 3-sialyllactose to xanthosine in biopsy specimen-matched urine supernatants best discriminated acute cellular rejection biopsy specimens from specimens without rejection. For clinical application, we developed a high-throughput mass spectrometry-based assay that enabled absolute and rapid quantification of the 3-sialyllactose-to-xanthosine ratio in urine samples. A composite signature of ratios of 3-sialyllactose to xanthosine and quinolinate to X-16397 and our previously reported urinary cell mRNA signature of 18S ribosomal RNA, CD3ε mRNA, and interferon-inducible protein-10 mRNA outperformed the metabolite signatures and the mRNA signature. The area under the receiver operating characteristics curve for the composite metabolite-mRNA signature was 0.93, and the signature was diagnostic of acute cellular rejection with a specificity of 84% and a sensitivity of 90%. The composite signature, developed using solely biopsy specimen-matched urine samples, predicted future acute cellular rejection when applied to pristine samples taken days to weeks before biopsy. We conclude that metabolite profiling of urine offers a noninvasive means of diagnosing and prognosticating acute cellular rejection in the human kidney allograft, and that the combined metabolite and mRNA signature is diagnostic and prognostic of acute cellular rejection with very high accuracy.

  16. Until they have faces: the ethics of facial allograft transplantation.

    PubMed

    Agich, G J; Siemionow, M

    2005-12-01

    The ethical discussion of facial allograft transplantation (FAT) for severe facial deformity, popularly known as facial transplantation, has been one sided and sensationalistic. It is based on film and fiction rather than science and clinical experience. Based on our experience in developing the first IRB approved protocol for FAT, we critically discuss the problems with this discussion, which overlooks the plight of individuals with severe facial deformities. We discuss why FAT for facial deformity is ethically and surgically justified despite its negative portrayal in the media.

  17. Microvascular transplantation of epiphyseal plates: studies utilizing allograft donor material.

    PubMed

    Boyer, Martin I; Bowen, C Vaughan A

    2007-01-01

    Compromised function of an epiphyseal plate caused by trauma, tumor, infection, or congenital malformation can result in significant musculoskeletal deformity. Techniques used to correct or minimize the extent of these deformities include autogenous or allogeneic cancellous bone grafts, nonvascularized cortical allografts, vascularized bone and composite tissue transfers, and distraction osteogenesis. These solutions are not ideal for children because they do not adequately address the actively growing nature of the extremity. Microvascular techniques have enabled the experimental transplantation of vascularized epiphyseal plates with high levels of postoperative viability and subsequent growth and offer a potential advantage over conventional treatments.

  18. Mechanisms involved in antibody- and complement-mediated allograft rejection

    PubMed Central

    2010-01-01

    Antibody-mediated rejection has become critical clinically because this form of rejection is usually unresponsive to conventional anti-rejection therapy, and therefore, it has been recognized as a major cause of allograft loss. Our group developed experimental animal models of vascularized organ transplantation to study pathogenesis of antibody- and complement-mediated endothelial cell injury leading to graft rejection. In this review, we discuss mechanisms of antibody-mediated graft rejection resulting from activation of complement by C1q- and MBL (mannose-binding lectin)-dependent pathways and interactions with a variety of effector cells, including macrophages and monocytes through Fcγ receptors and complement receptors. PMID:20135240

  19. Vascularized composite allograft-specific characteristics of immune responses.

    PubMed

    Issa, Fadi

    2016-06-01

    Vascularized composite allograft (VCA) transplantation, or reconstructive transplantation, has revolutionized the treatment of complex tissue and functional defects. Despite arriving during an age in which the immunology of solid organ transplant rejection has been investigated in much detail, these transplants have offered new perspectives from which to explore the immunobiology of transplantation. VCAs have a number of unique molecular, cellular, and architectural features which alter the character and intensity of the rejection response. While much is yet to be clarified, an understanding of these distinct mechanisms affords new possibilities for the control of immune responses in an effort to improve outcomes after VCA transplantation.

  20. [Microradiographic aspects of massive bone allografts in man].

    PubMed

    Coutelier, L; Delloye, C; de Nayer, P; Vincent, A

    1984-01-01

    Two stored frozen massive bone allografts were implanted after resection of femoral and tibial tumours in two patients. Eighteen and thirty months later the authors had the opportunity to make a microscopic examination of the grafts. The cortical bone grafts were incorporated by the classic "creeping substitution." The repair of the cortical transplant was very incomplete and showed large resorption cavities. The newly-formed living bone was not fully mineralized. These phenomena related only to the outer area of the cortical bone, the dead intra-cortical area being left unaffected by the process. Cancellous bone graft repair was faster and more efficient.

  1. Stem cell autograft and allograft in autoimmune diseases.

    PubMed

    De Cata, Angelo; Matarangolo, Angela; Inglese, Michele; Rubino, Rosa; Mazzoccoli, Gianluigi

    2016-02-01

    Autoimmune diseases are characterized by an insufficiency of immune tolerance and, although treated with a number of useful drugs, may need more unconventional therapeutic strategies for their more severe presentations. Among such unconventional therapeutic approaches, stem cell autograft and allograft have been used, with the aim of stimulating disease remission by modifying the pathogenic mechanisms that induce anomalous responses against self-antigens. Autologous transplantation is performed with the purpose of retuning autoimmune cells, whereas allogeneic transplantation is performed with the purpose of replacing anomalous immune effectors and mediators. In this article, we comprehensively review up-to-date information on the autoimmune diseases for which the transplantation of stem cells is indicated.

  2. Five different profiles of dihydropyridines in blocking T-type Ca(2+) channel subtypes (Ca(v)3.1 (alpha(1G)), Ca(v)3.2 (alpha(1H)), and Ca(v)3.3 (alpha(1I))) expressed in Xenopus oocytes.

    PubMed

    Furukawa, Taiji; Nukada, Toshihide; Namiki, Yoshiko; Miyashita, Yoriko; Hatsuno, Kento; Ueno, Yasunari; Yamakawa, Takeshi; Isshiki, Takaaki

    2009-06-24

    1,4-dihydropyridine (DHP) Ca(2+) antagonists have recently been shown to block T-type Ca(2+) channels, which may render favorable actions on cardiovascular systems. However, this evaluation remains to be done systematically for each T-type Ca(2+) channel subtype except for the Ca(v)3.1 (alpha(1G)) subtype. To address this issue at the molecular level, blocking effects of 14 kinds of DHPs (amlodipine, aranidipine, azelnidipine, barnidipine, benidipine, cilnidipine, efonidipine, felodipine, manidipine, nicardipine, nifedipine, nilvadipine, nimodipine, nitrendipine), which are clinically used for treatments of hypertension, on 3 subtypes of T-type Ca(2+) channels [Ca(v)3.2 (alpha(1H)), Ca(v)3.3 (alpha(1I)), and Ca(v)3.1 (alpha(1G))] were investigated in the Xenopus oocyte expression system using the two-microelectrode voltage-clamp technique. These 3 kinds (alpha(1H), alpha(1I) and alpha(1G)) of T-type channels were blocked by amlodipine, manidipine and nicardipine. On the other hand, azelnidipine, barnidipine, benidipine and efonidipine significantly blocked alpha(1H) and alpha(1G), but not alpha(1I) channels, while nilvadipine and nimodipine apparently blocked alpha(1H) and alpha(1I), but not alpha(1G) channels. Moreover, aranidipine blocked only alpha(1H) channels. By contrast, cilnidipine, felodipine, nifedipine and nitrendipine had little effects on these subtypes of T-type channels. The result indicates that the blockade of T-type Ca(2+) channels by derivatives of DHP Ca(2+) antagonist was selective for the channel subtype. Therefore, these selectivities of DHPs in blocking T-type Ca(2+) channel subtypes would provide useful pharmacological and clinical information on the mode of action of the drugs including side-effects and adverse effects.

  3. Beta-adrenergic-regulated phosphorylation of the skeletal muscle Ca(V)1.1 channel in the fight-or-flight response.

    PubMed

    Emrick, Michelle A; Sadilek, Martin; Konoki, Keiichi; Catterall, William A

    2010-10-26

    Ca(V)1 channels initiate excitation-contraction coupling in skeletal and cardiac muscle. During the fight-or-flight response, epinephrine released by the adrenal medulla and norepinephrine released from sympathetic nerves increase muscle contractility by activation of the β-adrenergic receptor/cAMP-dependent protein kinase pathway and up-regulation of Ca(V)1 channels in skeletal and cardiac muscle. Although the physiological mechanism of this pathway is well defined, the molecular mechanism and the sites of protein phosphorylation required for Ca(V)1 channel regulation are unknown. To identify the regulatory sites of phosphorylation under physiologically relevant conditions, Ca(V)1.1 channels were purified from skeletal muscle and sites of phosphorylation on the α1 subunit were identified by mass spectrometry. Two phosphorylation sites were identified in the proximal C-terminal domain, serine 1575 (S1575) and threonine 1579 (T1579), which are conserved in cardiac Ca(V)1.2 channels (S1700 and T1704, respectively). In vitro phosphorylation revealed that Ca(V)1.1-S1575 is a substrate for both cAMP-dependent protein kinase and calcium/calmodulin-dependent protein kinase II, whereas Ca(V)1.1-T1579 is a substrate for casein kinase 2. Treatment of rabbits with isoproterenol to activate β-adrenergic receptors increased phosphorylation of S1575 in skeletal muscle Ca(V)1.1 channels in vivo, and treatment with propranolol to inhibit β-adrenergic receptors reduced phosphorylation. As S1575 and T1579 in Ca(V)1.1 channels and their homologs in Ca(V)1.2 channels are located at a key regulatory interface between the distal and proximal C-terminal domains, it is likely that phosphorylation of these sites in skeletal and cardiac muscle is directly involved in calcium channel regulation in response to the sympathetic nervous system in the fight-or-flight response.

  4. β-Adrenergic–regulated phosphorylation of the skeletal muscle CaV1.1 channel in the fight-or-flight response

    PubMed Central

    Emrick, Michelle A.; Sadilek, Martin; Konoki, Keiichi; Catterall, William A.

    2010-01-01

    CaV1 channels initiate excitation–contraction coupling in skeletal and cardiac muscle. During the fight-or-flight response, epinephrine released by the adrenal medulla and norepinephrine released from sympathetic nerves increase muscle contractility by activation of the β-adrenergic receptor/cAMP-dependent protein kinase pathway and up-regulation of CaV1 channels in skeletal and cardiac muscle. Although the physiological mechanism of this pathway is well defined, the molecular mechanism and the sites of protein phosphorylation required for CaV1 channel regulation are unknown. To identify the regulatory sites of phosphorylation under physiologically relevant conditions, CaV1.1 channels were purified from skeletal muscle and sites of phosphorylation on the α1 subunit were identified by mass spectrometry. Two phosphorylation sites were identified in the proximal C-terminal domain, serine 1575 (S1575) and threonine 1579 (T1579), which are conserved in cardiac CaV1.2 channels (S1700 and T1704, respectively). In vitro phosphorylation revealed that CaV1.1-S1575 is a substrate for both cAMP-dependent protein kinase and calcium/calmodulin-dependent protein kinase II, whereas CaV1.1-T1579 is a substrate for casein kinase 2. Treatment of rabbits with isoproterenol to activate β-adrenergic receptors increased phosphorylation of S1575 in skeletal muscle CaV1.1 channels in vivo, and treatment with propranolol to inhibit β-adrenergic receptors reduced phosphorylation. As S1575 and T1579 in CaV1.1 channels and their homologs in CaV1.2 channels are located at a key regulatory interface between the distal and proximal C-terminal domains, it is likely that phosphorylation of these sites in skeletal and cardiac muscle is directly involved in calcium channel regulation in response to the sympathetic nervous system in the fight-or-flight response. PMID:20937870

  5. Ser1928 phosphorylation by PKA stimulates the L-type Ca2+ channel CaV1.2 and vasoconstriction during acute hyperglycemia and diabetes

    PubMed Central

    Nystoriak, Matthew A.; Nieves-Cintrón, Madeline; Patriarchi, Tommaso; Buonarati, Olivia R.; Prada, Maria Paz; Morotti, Stefano; Grandi, Eleonora; Fernandes, Julia Dos Santos; Forbush, Katherine; Hofmann, Franz; Sasse, Kent C.; Scott, John D.; Ward, Sean M.; Hell, Johannes W.; Navedo, Manuel F.

    2017-01-01

    Hypercontractility of arterial myocytes and enhanced vascular tone during diabetes are, in part, attributed to the effects of increased glucose (hyperglycemia) on L-type CaV1.2 channels. In murine arterial myocytes, kinase-dependent mechanisms mediate the increase in CaV1.2 activity in response to increased extracellular glucose. We identified a subpopulation of the CaV1.2 channel pore-forming subunit (α1C) within nanometer proximity of protein kinase A (PKA) at the sarcolemma of murine and human arterial myocytes. This arrangement depended upon scaffolding of PKA by an A-kinase anchoring protein 150 (AKAP150) in mice. Glucose-mediated increases in CaV1.2 channel activity were associated with PKA activity, leading to α1C phosphorylation at Ser1928. Compared to arteries from low-fat diet (LFD)–fed mice and nondiabetic patients, arteries from high-fat diet (HFD)–fed mice and from diabetic patients had increased Ser1928 phosphorylation and CaV1.2 activity. Arterial myocytes and arteries from mice lacking AKAP150 or expressing mutant AKAP150 unable to bind PKA did not exhibit increased Ser1928 phosphorylation and CaV1.2 current density in response to increased glucose or to HFD. Consistent with a functional role for Ser1928 phosphorylation, arterial myocytes and arteries from knockin mice expressing a CaV1.2 with Ser1928 mutated to alanine (S1928A) lacked glucose-mediated increases in CaV1.2 activity and vasoconstriction. Furthermore, the HFD-induced increases in CaV1.2 current density and myogenic tone were prevented in S1928A knockin mice. These findings reveal an essential role for α1C phosphorylation at Ser1928 in stimulating CaV1.2 channel activity and vasoconstriction by AKAP-targeted PKA upon exposure to increased glucose and in diabetes. PMID:28119464

  6. Can Skin Allograft Occasionally Act as a Permanent Coverage in Deep Burns? A Pilot Study 

    PubMed Central

    Rezaei, Ezzatollah; Beiraghi-Toosi, Arash; Ahmadabadi, Ali; Tavousi, Seyed Hassan; Alipour Tabrizi, Arash; Fotuhi, Kazem; Jabbari Nooghabi, Mehdi; Manafi, Amir; Ahmadi Moghadam, Shokoofeh

    2017-01-01

    BACKGROUND Skin allograft is the gold standard of wound coverage in patients with extensive burns; however, it is considered as a temporary wound coverage and rejection of the skin allograft is considered inevitable. In our study, skin allograft as a permanent coverage in deep burns is evaluated. METHODS Skin allograft survival was assessed in 38 patients from March 2009 to March 2014, retrospectively. Because of the lack of tissue specimen from the skin donors, patients with long skin allograft survival in whom the gender of donor and recipient of allograft was the same were excluded. Seven cases with skin allograft longevity and opposite gender in donor and recipient were finally enrolled. A polymerase chain reaction (PCR) test on the biopsy specimen from recipients and donors were undertaken. RESULTS PCR on the biopsy specimen from recipients confirmed those specimens belong to the donors. All patients received allograft from the opposite sex. Two (28.57%) patients received allograft from their first-degree blood relatives, and in one (14.29%) case, the allograft was harvested from an alive individual with no blood relation. The rest were harvested from multiorgan donors. In eight months of follow up, no clinical evidence of graft rejection was noted. CONCLUSION Long term persistence of skin allograft in patients is worthy of more attention. Further studies An increase in knowledge of factors influencing this longevity could realize the dream of burn surgeons to achieve a permanent coverage other than autograft for major burn patients.

  7. Role of extracellular Ca2+ in gating of CaV1.2 channels

    PubMed Central

    Babich, Olga; Isaev, Dmytro; Shirokov, Roman

    2005-01-01

    We examined changes in ionic and gating currents in CaV1.2 channels when extracellular Ca2+ was reduced from 10 mm to 0.1 μm. Saturating gating currents decreased by two-thirds (KD≈ 40 μm) and ionic currents increased 5-fold (KD≈ 0.5 μm) due to increasing Na+ conductance. A biphasic time dependence for the activation of ionic currents was observed at low [Ca2+], which appeared to reflect the rapid activation of channels that were not blocked by Ca2+ and a slower reversal of Ca2+ blockade of the remaining channels. Removal of Ca2+ following inactivation of Ca2+ currents showed that Na+ currents were not affected by Ca2+-dependent inactivation. Ca2+-dependent inactivation also induced a negative shift of the reversal potential for ionic currents suggesting that inactivation alters channel selectivity. Our findings suggest that activation of Ca2+ conductance and Ca2+-dependent inactivation depend on extracellular Ca2+ and are linked to changes in selectivity. PMID:15845581

  8. Extension of CAVS coarse-grained model to phospholipid membranes: The importance of electrostatics.

    PubMed

    Shen, Hujun; Deng, Mingsen; Zhang, Yachao

    2017-05-15

    It is evident from experiment that electrostatic potential (or dipole potential) is positive inside PC or PE lipid bilayers in the absence of ions. MARTINI coarse-grained (CG) model, which has been widely used in simulating physical properties of lipid bilayers, fails to reproduce the positive value for the dipole potential in the membrane interior. Although the total dipole potential can be correctly described by the BMW/MARTINI model, the contribution from the ester dipoles, playing a nontrivial role in the electrostatic potential across lipid membranes, is neglected by this hybrid approach. In the ELBA CG model, the role of the ester dipoles is considered, but it is overweighed because various atomistic models have consistently shown that water is actually the leading contributor of dipole potential. Here, we present a CG approach by combining the BMW-like water model (namely CAVS model) with the ELBA-like lipid model proposed in this work. Our CG model was designed not only to correctly reproduce the positive values for the dipole potential inside PC and PE lipid bilayers but also to properly balance the individual contributions from the ester dipoles and water, surmounting the limitations of current CG models in the calculations of dipole potential. © 2017 Wiley Periodicals, Inc.

  9. Chemical composition and antifungal activity of the essential oils of Lavandula pedunculata (Miller) Cav.

    PubMed

    Zuzarte, Monica; Gonçalves, Maria J; Cavaleiro, Carlos; Dinis, Augusto M; Canhoto, Jorge M; Salgueiro, Lígia R

    2009-08-01

    The chemical composition and antifungal activity of the essential oils of Lavandula pedunculata (Miller) Cav., harvested in North and Central Portugal, were investigated. The essential oils were isolated by hydrodistillation and analyzed by GC and GC/MS. The minimal-inhibitory concentration (MIC) and the minimal-lethal concentration (MLC) of the essential oils and of their major constituents were used to evaluate the antifungal activity against different strains of fungi involved in candidosis, dematophytosis, and aspergillosis. The oils were characterized by a high percentage of oxygenated monoterpenes, the main compounds being 1,8-cineole (2.4-55.5%), fenchone (1.3-59.7%), and camphor (3.6-48.0%). Statistical analysis differentiated the essential oils into two main types, one characterized by the predominance of fenchone and the other one by the predominance of 1,8-cineole. Within the 1,8-cineole chemotype, two subgroups were well-defined taking into account the percentages of camphor. A significant antifungal activity of the oils was found against dermatophyte strains. The essential oil with the highest content of camphor was the most active with MIC and MLC values ranging from 0.32-0.64 microl/ml.

  10. [Value of multiple cortical perforations for the rehabilitation of massive deep-frozen bone allografts. Experimental study in sheep].

    PubMed

    Simon, P; Babin, S R; Delloye, C; Schmitt, D

    1992-01-01

    Incorporation of massive cortical bone allografts in human is slow and remains incomplete. Late biopsies of implanted allografts or histological studies of explanted allografts always show the partial substitution of necrotic bone by new bone from the host. The aim of the present study was to evaluate the effect of drilling the massive deep-frozen cortical allografts in order to induce osteogenesis. Thirteen sheep were operated on and a standard segment of the proximal ulna was removed and the gap filled either by an unperforated allograft or by a perforated one. Based on histological and microradiographic examination, a quite complete substitution of the perforated allografts was observed but in this model no statistically significant difference was observed between perforated and unperforated allografts. Further study is needed to assess the effect of the perforations.

  11. Coexpression of high-voltage-activated ion channels Kv3.4 and Cav1.2 in pioneer axons during pathfinding in the developing rat forebrain.

    PubMed

    Huang, Chia-Yi; Chu, Dachen; Hwang, Wei-Chao; Tsaur, Meei-Ling

    2012-11-01

    Precise axon pathfinding is crucial for establishment of the initial neuronal network during development. Pioneer axons navigate without the help of preexisting axons and pave the way for follower axons that project later. Voltage-gated ion channels make up the intrinsic electrical activity of pioneer axons and regulate axon pathfinding. To elucidate which channel molecules are present in pioneer axons, immunohistochemical analysis was performed to examine 14 voltage-gated ion channels (Kv1.1-Kv1.3, Kv3.1-Kv3.4, Kv4.3, Cav1.2, Cav1.3, Cav2.2, Nav1.2, Nav1.6, and Nav1.9) in nine axonal tracts in the developing rat forebrain, including the optic nerve, corpus callosum, corticofugal fibers, thalamocortical axons, lateral olfactory tract, hippocamposeptal projection, anterior commissure, hippocampal commissure, and medial longitudinal fasciculus. We found A-type K⁺ channel Kv3.4 in both pioneer axons and early follower axons and L-type Ca²⁺ channel Cav1.2 in pioneer axons and early and late follower axons. Spatially, Kv3.4 and Cav1.2 were colocalized with markers of pioneer neurons and pioneer axons, such as deleted in colorectal cancer (DCC), in most fiber tracts examined. Temporally, Kv3.4 and Cav1.2 were expressed abundantly in most fiber tracts during axon pathfinding but were downregulated beginning in synaptogenesis. By contrast, delayed rectifier Kv channels (e.g., Kv1.1) and Nav channels (e.g., Nav1.2) were absent from these fiber tracts (except for the corpus callosum) during pathfinding of pioneer axons. These data suggest that Kv3.4 and Cav1.2, two high-voltage-activated ion channels, may act together to control Ca²⁺ -dependent electrical activity of pioneer axons and play important roles during axon pathfinding.

  12. PKA and phosphatases attached to the Ca(V)1.2 channel regulate channel activity in cell-free patches.

    PubMed

    Xu, Jianjun; Yu, Lifeng; Minobe, Etsuko; Lu, Liting; Lei, Ming; Kameyama, Masaki

    2016-01-15

    Calmodulin (CaM) + ATP can reprime voltage-gated L-type Ca(2+) channels (Ca(V)1.2) in inside-out patches for activation, but this effect decreases time dependently. This suggests that the Ca(V)1.2 channel activity is regulated by additional cytoplasmic factors. To test this hypothesis, we examined the role of cAMP-dependent protein kinase A (PKA) and protein phosphatases in the regulation of Ca(V)1.2 channel activity in the inside-out mode in guinea pig ventricular myocytes. Ca(V)1.2 channel activity quickly disappeared after the patch was excised from the cell and recovered to only 9% of that in the cell-attached mode on application of CaM + ATP at 10 min after the inside out. However, immediate exposure of the excised patch to the catalytic subunit of PKA + ATP or the nonspecific phosphatase inhibitor okadaic acid significantly increased the Ca(V)1.2 channel activity recovery by CaM + ATP (114 and 96%, respectively) at 10 min. Interestingly, incubation of the excised patches with cAMP + ATP also increased CaM/ATP-induced Ca(V)1.2 channel activity recovery (108%), and this effect was blocked by the nonspecific protein kinase inhibitor K252a. The channel activity in the inside-out mode was not maintained by either catalytic subunit of PKA or cAMP + ATP in the absence of CaM, but was stably maintained in the presence of CaM for more than 40 min. These results suggest that PKA and phosphatase(s) attached on or near the Ca(V)1.2 channel regulate the basal channel activity, presumably through modulation of the dynamic CaM interaction with the channel.

  13. Review: Cav2.3 R-type Voltage-Gated Ca2+ Channels - Functional Implications in Convulsive and Non-convulsive Seizure Activity

    PubMed Central

    Wormuth, Carola; Lundt, Andreas; Henseler, Christina; Müller, Ralf; Broich, Karl; Papazoglou, Anna; Weiergräber, Marco

    2016-01-01

    Background: Researchers have gained substantial insight into mechanisms of synaptic transmission, hyperexcitability, excitotoxicity and neurodegeneration within the last decades. Voltage-gated Ca2+ channels are of central relevance in these processes. In particular, they are key elements in the etiopathogenesis of numerous seizure types and epilepsies. Earlier studies predominantly targeted on Cav2.1 P/Q-type and Cav3.2 T-type Ca2+ channels relevant for absence epileptogenesis. Recent findings bring other channels entities more into focus such as the Cav2.3 R-type Ca2+ channel which exhibits an intriguing role in ictogenesis and seizure propagation. Cav2.3 R-type voltage gated Ca2+ channels (VGCC) emerged to be important factors in the pathogenesis of absence epilepsy, human juvenile myoclonic epilepsy (JME), and cellular epileptiform activity, e.g. in CA1 neurons. They also serve as potential target for various antiepileptic drugs, such as lamotrigine and topiramate. Objective: This review provides a summary of structure, function and pharmacology of VGCCs and their fundamental role in cellular Ca2+ homeostasis. We elaborate the unique modulatory properties of Cav2.3 R-type Ca2+ channels and point to recent findings in the proictogenic and proneuroapoptotic role of Cav2.3 R-type VGCCs in generalized convulsive tonic–clonic and complex-partial hippocampal seizures and its role in non-convulsive absence like seizure activity. Conclusion: Development of novel Cav2.3 specific modulators can be effective in the pharmacological treatment of epilepsies and other neurological disorders. PMID:27843503

  14. Ca2+-binding protein-1 facilitates and forms a postsynaptic complex with Cav1.2 (L-type) Ca2+ channels.

    PubMed

    Zhou, Hong; Kim, Seong-Ah; Kirk, Elizabeth A; Tippens, Alyssa L; Sun, Hong; Haeseleer, Françoise; Lee, Amy

    2004-05-12

    Ca2+-binding protein-1 (CaBP1) is a Ca2+-binding protein that is closely related to calmodulin (CaM) and localized in somatodendritic regions of principal neurons throughout the brain, but how CaBP1 participates in postsynaptic Ca2+ signaling is not known. Here, we describe a novel role for CaBP1 in the regulation of Ca2+ influx through Ca(v)1.2 (L-type) Ca2+ channels. CaBP1 interacts directly with the alpha1 subunit of Ca(v)1.2 at sites that also bind CaM. CaBP1 binding to one of these sites, the IQ domain, is Ca2+ dependent and competitive with CaM binding. The physiological significance of this interaction is supported by the association of Ca(v)1.2 and CaBP1 in postsynaptic density fractions purified from rat brain. Moreover, in double-label immunofluorescence experiments, CaBP1 and Ca(v)1.2 colocalize in numerous cell bodies and dendrites of neurons, particularly in pyramidal cells in the CA3 region of the hippocampus and in the dorsal cortex. In electrophysiological recordings of cells transfected with Ca(v)1.2, CaBP1 greatly prolonged Ca2+ currents, prevented Ca2+-dependent inactivation, and caused Ca2+-dependent facilitation of currents evoked by step depolarizations and repetitive stimuli. These effects contrast with those of CaM, which promoted strong Ca2+-dependent inactivation of Ca(v)1.2 with these same voltage protocols. Our findings reveal how Ca2+-binding proteins, such as CaM and CaBP1, differentially adjust Ca2+ influx through Ca(v)1.2 channels, which may specify diverse modes of Ca2+ signaling in neurons.

  15. Immunohistological observations in rat kidney allografts after local steroid administration

    PubMed Central

    1987-01-01

    In this report we investigated local regulatory mechanisms in graft rejection and their response to local immunosuppressive therapy. For this purpose local immunosuppression was induced in rat kidney allografts by intrarenal infusion of prednisolone. Intrarenal drug delivery resulted in high drug levels within the graft and low systemic drug levels. Systemic drug levels were by themselves not sufficiently immunosuppressive to induce graft survival, and local prednisolone levels within the graft proved to be responsible for prolongation of graft survival. During intrarenal drug delivery, systemic responsiveness to the renal allograft proved normal, since intrarenally treated grafts were infiltrated by MHC class II-positive host cells and, except for a somewhat lower percentage of macrophages, cellular infiltration in intrarenal treated grafts was comparable to untreated grafts. However, T cells and macrophages present in intrarenally treated grafts were not able to destroy the grafted tissue. Local immunosuppressive therapy resulted in inhibition of IL-2-R expression, absence of IFN-gamma, and prevention of MHC class II induction on grafted tissue. These observations strongly indicate the presence of local regulatory mechanisms in graft rejection. The experimental model described can be used for further analysis of these intragraft events. Moreover, the results demonstrate that local immunosuppressive therapy can contribute to effective inhibition of cellular immune response in graft rejection. PMID:3119756

  16. Reassortment of lymphocytes in lymph from normal and allografted sheep.

    PubMed Central

    Miller, H. R.; Adams, E. P.

    1977-01-01

    The distribution and nature of surface immunoglobulin-bearing (SIg) cells were studied in various sources of lymph from normal sheep and from sheep bearing renal autografts and renal allografts. In normal sheep, 12.2% +/- 1.5 of all mononuclear cells in peripheral lymph SIg and, of these, more than 50% were monocytes and macrophages. Less than 6% of the lymphocytes in peripheral lymph carried SIg. In contrast, 24.7% +/- 1.3 of the mononuclear cells in central lymph had SIg, and all of the labeled cells were lymphocytes. The frequencies of SIg cells in peripheral lymph issuing from renal autografts and from renal allografts were 6.7% +/- 1.3 and 6.9% +/- 0.8, respectively, and the labeled cells were predominantly lymphocytes. The proportion of SIg cells in central lymph from graft-bearing sheep was similar to that from normal sheep. The differences between central lymph and peripheral lymph from both normal and graft-bearing sheep are thought to reflect a restriction on the passage of SIg cells through capillary endothelium in nonlymphoid tissues. Images Figure 3 Figure 4 Figure 5 Figure 6 Figure 1 Figure 2 PMID:322506

  17. Mechanical integrity of subchondral bone in osteochondral autografts and allografts

    PubMed Central

    Wohl, Greg; Goplen, Gordon; Ford, Jason; Novak, Kelli; Hurtig, Mark; McPherson, Roger; McGann, Locksley; Schachar, Norman; Zernicke, Ronald F.

    1998-01-01

    Objective To assess the influence of osteochondral graft preservation techniques on post-transplant biomechanics of graft and host subchondral bone in the knee joint. Design An experimental animal model (sheep), specifically the weight-bearing articular surface of the medial femoral condyle of the knee joints. Intervention Each sheep received, in the ipsilateral knee, an allograft that was (a) frozen without dimethyl sulfoxide (DMSO), (b) snap-frozen in liquid nitrogen or (c) frozen with DMSO. The contralateral knee received an autograft that was (a) snap-frozen, (b) treated with DMSO or (c) left untreated (fresh). Main outcome measures Mechanical and material properties of bone, including maximal compression stress, modulus of elasticity and bone mineral ash content of subchondral bone cores (from the graft centre and surrounding host bone). Results No significant differences were found in the mechanical properties of the subchondral bone under the graft, but there were significant changes in surrounding bone. Bone surrounding the grafts that were snap-frozen or frozen without DMSO was significantly stronger than the normal control bone. However, bone surrounding fresh autografts and cryoprotected allografts was not significantly different from normal control bone. Conclusions The changes in the mechanical behaviour of the host bone may be associated with graft cell viability. The greater stiffness of the subchondral host bone may have consequences for long-term graft integrity and for the development of degenerative osteoarthritis. PMID:9627549

  18. Meniscal allograft sterilisation: effect on biomechanical and histological properties.

    PubMed

    Bui, David; Lovric, Vedran; Oliver, Rema; Bertollo, Nicky; Broe, David; Walsh, William R

    2015-09-01

    Sterilisation of allografts are a crucial step in ensuring safety and viability. Current sterilisation standards such as 25 kGy gamma irradiation (γ) can have adverse effects on the ultrastructure and biomechanical properties of allograft tissue. Supercritical CO2 (SCCO2) technology, represents an improved sterilisation process that potentially preserves tissue properties. This study aimed to test the effect of SCCO2 sterilisation on the biomechanical and histological properties of the meniscus and compare this to the current standard of γ. Thirty-two 18-month old ovine menisci were randomly assigned into three groups for sterilisation (SCCO2, γ and control). After treatment, biomechanical indentation testing (stiffness and stress relaxation) or histological analysis [percentage of void, cells and extracellular matrix (ECM) per slide] was undertaken. Both SCCO2 and gamma groups displayed an increase in stiffness and stress relaxation as compared to control, however, this difference was lesser in samples treated with SCCO2. No significant histological quantitative differences were detected between SCCO2 and control specimens. Gamma-treated samples demonstrated a significant increase in void and decrease in ECM. Interestingly, both treatment groups demonstrated a decreasing mean void and increasing ECM percentage when analysed from outer to inner zones. No significant differences were detected in all-endpoints when analysed by section. SCCO2 sterilisation represents a potential feasible alternative to existing sterilization techniques such as γ.

  19. Tissue banking in India: gamma-irradiated allografts.

    PubMed

    Lobo Gajiwala, A

    2003-01-01

    In India, the procurement of tissues for transplantation is governed by the Transplantation of Human Organs Act, 1994. Although this law exists, it is primarily applied to organ transplantation and rules and regulations that are specific to tissue banking which have yet to be developed. The Tata Memorial Hospital (TMH) Tissue Bank was started in 1988 as part of an International Atomic Energy Agency (IAEA) programme to promote the use of ionising radiation for the sterilisation of biological tissues. It represents the Government of India within this project and was the first facility in the country to use radiation for the sterilisation of allografts. It is registered with the Health Services Maharashtra State and provides freeze-dried, gamma irradiated amnion, dura mater, skin and bone. The tissues are obtained either from cadavers or live donors. To date the TMH Tissue Bank has provided 6328 allografts which have found use as biological dressings and in various reconstructive procedures. The TMH Tissue Bank has helped initiate a Tissue Bank at the Defence Laboratory (DL), Jodhpur. At present these are the only two Banks in the country using radiation for the terminal sterilisation of preserved tissues. The availability of safe, clinically useful and cost effective grafts has stimulated innovative approaches to surgery. There is an increased demand for banked tissues and a heightened interest in the development of tissue banks. Inadequate infrastructure for donor referral programmes and the lack of support for tissue transplant co-ordinators however, continue to limit the availability of donor tissue.

  20. Utility of an allograft tendon for scoliosis correction via the costo-transverse foreman.

    PubMed

    Sun, Dong; McCarthy, Michael; Dooley, Adam C; Ramakrishnaiah, Raghu H; Shelton, R Shane; McLaren, Sandra G; Skinner, Robert A; Suva, Larry J; McCarthy, Richard E

    2017-01-01

    Current convex tethering techniques for treatment of scoliosis have centered on anterior convex staples or polypropylene tethers. We hypothesized that an allograft tendon tether inserted via the costo-transverse foramen would correct an established spinal deformity. In the pilot study, six 8-week-old pigs underwent allograft tendon tethering via the costo-transverse foreman or sham to test the strength of the transplanted tendon to retard spine growth. After 4 months, spinal deformity in three planes was induced in all animals with allograft tendons. In the treatment study, the allograft tendon tether was used to treat established scoliosis in 11 8-week-old pigs (spinal deformity > 50°). Once the deformity was observed (4 months) animals were assigned to either no treatment group or allograft tendon tether group and progression assessed by monthly radiographs. At final follow-up, coronal Cobb angle and maximum vertebral axial rotation of the treatment group was significantly smaller than the non-treatment group, whereas sagittal kyphosis of the treatment group was significantly larger than the non-treatment group. In sum, a significant correction was achieved using a unilateral allograft tendon spinal tether, suggesting that an allograft tendon tethering approach may represent a novel fusion-less procedure to correct idiopathic scoliosis. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:183-192, 2017.

  1. Renal cell carcinoma in kidney allografts: histologic types, including biphasic papillary carcinoma.

    PubMed

    Troxell, Megan L; Higgins, John P

    2016-11-01

    Kidney transplant recipients are at increased risk for malignancy, with about 5% incidence of cancer in native end-stage kidneys. Carcinoma in the renal allograft is far less common. Prior studies have demonstrated a propensity for renal cell carcinomas (RCCs) of papillary subtypes in end-stage kidneys, and perhaps in allograft kidneys, but most allograft studies lack detailed pathologic review and predate the current classification system. We reviewed our experience with renal carcinoma in kidney allografts at 2 academic centers applying the International Society of Urological Pathology classification, informed by immunohistochemistry. The incidence of renal allograft carcinoma was about 0.26% in our population. Of 12 allograft carcinomas, 6 were papillary (50%), 4 were clear cell (33%), 1 was clear cell (tubulo)papillary, and 1 chromophobe. Two of the papillary carcinomas had distinctive biphasic glomeruloid architecture matching the newly named "biphasic squamoid alveolar" pattern and were difficult to classify on core biopsies. The 2 cell types had different immunophenotypes in our hands (eosinophilic cells: RCC-/CK34betaE12+ weight keratin +/cyclin D1+; clear cells: RCC+/cytokeratin high molecular weight negative to weak/cyclin D1-). None of the patients experienced cancer recurrences or metastasis. Our study confirms the predilection for papillary RCCs in kidney allografts and highlights the occurrence of rare morphologic variants. Larger studies are needed with careful pathologic review, which has been lacking in the literature.

  2. Restrictive allograft syndrome post lung transplantation is characterized by pleuroparenchymal fibroelastosis.

    PubMed

    Ofek, Efrat; Sato, Masaaki; Saito, Tomohito; Wagnetz, Ute; Roberts, Heidi C; Chaparro, Cecilia; Waddell, Thomas K; Singer, Lianne G; Hutcheon, Michael A; Keshavjee, Shaf; Hwang, David M

    2013-03-01

    We previously described restrictive allograft syndrome as a form of chronic lung allograft dysfunction, demonstrating restrictive pulmonary function decline. However, the histopathological correlates of restrictive allograft syndrome have yet to be satisfactorily described. We hypothesized that pulmonary pleuroparenchymal fibroelastosis, as has recently been described in bone marrow transplant recipients, may also be present in the lungs of patients with restrictive allograft syndrome. Retrospective review of 493 patients who underwent lung transplantation between 1 January 1996 and 30 June 2009, was conducted. Out of 47 patients with clinical features of restrictive allograft syndrome, 16 had wedge biopsy, re-transplant lung explant, or autopsy lung specimens available for review. All lungs showed varying degrees of pleural fibrosis. Fifteen of 16 showed parenchymal fibroelastosis, characterized by hypocellular collagen deposition with preservation and thickening of the underlying alveolar septal elastic network. The fibroelastosis was predominantly subpleural in distribution, with some cases also showing centrilobular and paraseptal distribution. A sharp demarcation was often seen between areas of fibroelastosis and unaffected lung parenchyma, with fibroblastic foci often present at this interface. Concurrent features of obliterative bronchiolitis were present in 14 cases. Another common finding was the presence of diffuse alveolar damage (13 cases), usually in specimens obtained <1 year after clinical onset of restrictive allograft syndrome. The single specimen in which fibroelastosis was not identified was obtained before the clinical onset of chronic lung allograft dysfunction, and showed features of diffuse alveolar damage. In conclusion, pleuroparenchymal fibroelastosis is a major histopathologic correlate of restrictive allograft syndrome, and was often found concurrently with diffuse alveolar damage. Our findings support a temporal sequence of diffuse

  3. Quality control in tissue banking--ensuring the safety of allograft tissues.

    PubMed

    Humphries, Linda K; Mansavage, Vicki L

    2006-09-01

    DESPITE FEDERAL REGULATIONS for tissue-banking practices, inadequate quality control led to the largest allograft tissue recall in history in October 2005. THE RECALL INCLUDED all allograft tissues obtained from 761 donors and distributed by five tissue banks. Many of these tissues already had been implanted and were unrecoverable. THIS ARTICLE DESCRIBES the many tissue-banking industry variables, including donor selection and testing and tissue recovery, processing, and preservation. QUESTIONS THAT HEALTH CARE providers can ask to determine which tissue banks' quality control measures best ensure the safety of the allografts they provide also are included.

  4. Modulating Wnt Signaling Pathway to Enhance Allograft Integration in Orthopedic Trauma Treatment

    DTIC Science & Technology

    2013-10-01

    inhibitors Sost or DKK1 with monoclonal antibodies will enhance allograft integration to the host bone. The proposed work in this project was designed...Determine the effect of modulating the LRP-5/Wnt pathway with anti- Dkk1 monoclonal antibody on allograft incorporation in a rat segmental repair model using...bones from Fresh Frozen and Freeze-Dried allografts at 4, 8 and 12 week time points for saline, anti- Sost and anti- Dkk1 using µCT scanning. Data is

  5. Effect of a stable prostacyclin analogue on canine renal allograft rejection.

    PubMed Central

    Tobimatsu, M; Ueda, Y; Toyoda, K; Saito, S; Konomi, K

    1987-01-01

    The effect of OP-41483 (Ono Pharmaceutical Co., Osaka, Japan), a stable prostacyclin analogue, on canine renal allograft rejection was investigated. Administration for 4 days after transplantation significantly increased renal cortical blood flow and urine output when compared with untreated dogs with renal allografts. Serum creatinine levels remained relatively low during postoperative days 1-4. Mean animal survival time was prolonged. Vascular lesions and mononuclear cell infiltration were greatly diminished in biopsy specimens removed on day 4. This stable prostacyclin analogue provided a degree of protection against canine renal allograft rejection. Images Figs. 1A and B. PMID:3545109

  6. Biomechanical Evaluation of Posterior Cruciate Ligament Reconstruction With Quadriceps Versus Achilles Tendon Bone Block Allograft

    PubMed Central

    Forsythe, Brian; Haro, Marc S.; Bogunovic, Ljiljana; Collins, Michael J.; Arns, Thomas A.; Trella, Katie J.; Shewman, Elizabeth F.; Verma, Nikhil N.; Bach, Bernard R.

    2016-01-01

    Background: Long-term studies of posterior cruciate ligament (PCL) reconstruction suggest that normal stability is not restored in the majority of patients. The Achilles tendon allograft is frequently utilized, although recently, the quadriceps tendon has been introduced as an alternative option due to its size and high patellar bone density. Purpose/Hypothesis: The purpose of this study was to compare the biomechanical strength of PCL reconstructions using a quadriceps versus an Achilles allograft. The hypothesis was that quadriceps bone block allograft has comparable mechanical properties to those of Achilles bone block allograft. Study Design: Controlled laboratory study. Methods: Twenty-nine fresh-frozen cadaveric knees were assigned to 1 of 3 groups: (1) intact PCL, (2) PCL reconstruction with Achilles tendon allograft, or (3) PCL reconstruction with quadriceps tendon allograft. After reconstruction, all supporting capsular and ligamentous tissues were removed. Posterior tibial translation was measured at neutral and 20° external rotation. Each specimen underwent a preload, 2 cyclic loading protocols of 500 cycles, then load to failure. Results: Construct creep deformation was significantly lower in the intact group compared with both Achilles and quadriceps allograft (P = .008). The intact specimens reached the greatest ultimate load compared with both reconstructions (1974 ± 752 N, P = .0001). The difference in ultimate load for quadriceps versus Achilles allograft was significant (P = .048), with the quadriceps group having greater maximum force during failure testing. No significant differences were noted between quadriceps versus Achilles allograft for differences in crosshead excursion during cyclic testing (peak-valley [P-V] extension stretch), creep deformation, or stiffness. Construct stiffness measured during the failure test was greatest in the intact group (117 ± 9 N/mm, P = .0001) compared with the Achilles (43 ± 11 N/mm) and quadriceps (43

  7. Retinal Ganglion Cell Loss and Mild Vasculopathy in Methylene Tetrahydrofolate Reductase (Mthfr)-Deficient Mice: A Model of Mild Hyperhomocysteinemia

    PubMed Central

    Markand, Shanu; Saul, Alan; Roon, Penny; Prasad, Puttur; Martin, Pamela; Rozen, Rima; Ganapathy, Vadivel; Smith, Sylvia B.

    2015-01-01

    Purpose. Methylenetetrahydrofolate reductase (Mthfr) is a key enzyme in homocysteine-methionine metabolism. We investigated Mthfr expression in retina and asked whether mild hyperhomocysteinemia, due to Mthfr deficiency, alters retinal neurovascular structure and function. Methods. Expression of Mthfr was investigated at the gene and protein level using quantitative (q) RT-PCR, in situ hybridization, immunoblotting, and immunohistochemistry (IHC). The Mthfr+/+ and Mthfr+/− mice were subjected to comprehensive evaluation using ERG, funduscopy, fluorescein angiography (FA), spectral-domain optical coherence tomography (SD-OCT), HPLC, and morphometric and IHC analysis of glial fibrillary acidic protein (GFAP) at 8 to 24 weeks. Results. Gene and protein analyses disclosed widespread retinal expression of Mthfr. Electroretinography (ERG) revealed a significant decrease in positive scotopic threshold response in retinas of Mthfr+/− mice at 24 weeks. Fundus examination in mice from both groups was normal; FA revealed areas of focal vascular leakage in 20% of Mthfr+/− mice at 12 to 16 weeks and 60% by 24 weeks. The SD-OCT revealed a significant decrease in nerve fiber layer (NFL) thickness at 24 weeks in Mthfr+/− compared to Mthfr+/+ mice. There was a 2-fold elevation in retinal hcy at 24 weeks in Mthfr+/− mice by HPLC and IHC. Morphometric analysis revealed an approximately 20% reduction in cells in the ganglion cell layer of Mthfr+/− mice at 24 weeks. The IHC indicated significantly increased GFAP labeling suggestive of Müller cell activation. Conclusions. Mildly hyperhomocysteinemic Mthfr+/− mice demonstrate reduced ganglion cell function, thinner NFL, and mild vasculopathy by 24 weeks. The retinal phenotype is similar to that of hyperhomocysteinemic mice with deficiency of cystathionine-β-synthase (Cbs) reported earlier. The data support the hypothesis that hyperhomocysteinemia may be causative in certain retinal neurovasculopathies. PMID:25766590

  8. Impact of early transcranial Doppler screening and intensive therapy on cerebral vasculopathy outcome in a newborn sickle cell anemia cohort.

    PubMed

    Bernaudin, Françoise; Verlhac, Suzanne; Arnaud, Cécile; Kamdem, Annie; Chevret, Sylvie; Hau, Isabelle; Coïc, Lena; Leveillé, Emmanuella; Lemarchand, Elisabeth; Lesprit, Emmanuelle; Abadie, Isabelle; Medejel, Nadia; Madhi, Fouad; Lemerle, Sophie; Biscardi, Sandra; Bardakdjian, Josiane; Galactéros, Frédéric; Torres, Martine; Kuentz, Mathieu; Ferry, Christelle; Socié, Gérard; Reinert, Philippe; Delacourt, Christophe

    2011-01-27

    Transcranial Doppler (TCD) is used to detect children with sickle cell anemia (SCA) who are at risk for stroke, and transfusion programs significantly reduce stroke risk in patients with abnormal TCD. We describe the predictive factors and outcomes of cerebral vasculopathy in the Créteil newborn SCA cohort (n = 217 SS/Sβ(0)), who were early and yearly screened with TCD since 1992. Magnetic resonance imaging/magnetic resonance angiography was performed every 2 years after age 5 (or earlier in case of abnormal TCD). A transfusion program was recommended to patients with abnormal TCD and/or stenoses, hydroxyurea to symptomatic patients in absence of macrovasculopathy, and stem cell transplantation to those with human leukocyte antigen-genoidentical donor. Mean follow-up was 7.7 years (1609 patient-years). The cumulative risks by age 18 years were 1.9% (95% confidence interval [95% CI] 0.6%-5.9%) for overt stroke, 29.6% (95% CI 22.8%-38%) for abnormal TCD, which reached a plateau at age 9, whereas they were 22.6% (95% CI 15.0%-33.2%) for stenosis and 37.1% (95% CI 26.3%-50.7%) for silent stroke by age 14. Cumulating all events (stroke, abnormal TCD, stenoses, silent strokes), the cerebral risk by age 14 was 49.9% (95% CI 40.5%-59.3%); the independent predictive factors for cerebral risk were baseline reticulocytes count (hazard ratio 1.003/L × 10(9)/L increase, 95% CI 1.000-1.006; P = .04) and lactate dehydrogenase level (hazard ratio 2.78/1 IU/mL increase, 95% CI1.33-5.81; P = .007). Thus, early TCD screening and intensification therapy allowed the reduction of stroke-risk by age 18 from the previously reported 11% to 1.9%. In contrast, the 50% cumulative cerebral risk suggests the need for more preventive intervention.

  9. Intravitreal Anti-vascular Endothelial Growth Factor for Treating Polypoidal Choroidal Vasculopathy with Grape-like Polyp Clusters

    PubMed Central

    Chang, Young Suk; Kim, Jong Woo; Lee, Tae Gon; Kim, Chul Gu

    2016-01-01

    Purpose To evaluate 12-month outcomes of anti-vascular endothelial growth factor (VEGF) therapy for polypoidal choroidal vasculopathy (PCV) with grape-like polyp clusters. Methods This retrospective observational study included 23 eyes of 23 patients who were newly diagnosed with PCV with grape-like polyp clusters, and who were subsequently treated with anti-VEGF monotherapy. The study compares the best-corrected visual acuity (BCVA) of the patients at diagnosis, at 3 months, and at 12 months after diagnosis. In addition, 12-month changes in BCVA values were compared between cases with subfoveal or juxtafoveal polyps and cases with extrafoveal polyps. Results The baseline, 3-month, and 12-month logarithm of the minimal angle of resolution BCVA was 0.62 ± 0.35, 0.50 ± 0.43, and 0.58 ± 0.48, respectively. Compared to the baseline, patient BCVA was not significantly different at 12 months after diagnosis (p = 0.764). Six eyes (26.1%) gained ≥0.2 logarithm of the minimal angle of resolution BCVA. In cases with subfoveal or juxtafoveal polyps, BCVA values at baseline and at 12 months after diagnosis were 0.66 ± 0.37 and 0.69 ± 0.53, respectively. In cases with extrafoveal polyps, the values were 0.54 ± 0.33 and 0.37 ± 0.31, respectively. Changes in BCVA values were significantly different between the two groups (p = 0.023). Conclusions Although anti-VEGF therapy has favorable short-term efficacy for treating PCV with grape-like polyp clusters, long-term visual improvements are generally limited in the majority of afflicted eyes. The presence of subfoveal or juxtafoveal polyps may suggest unfavorable treatment outcomes. PMID:27478354

  10. Reduced-fluence photodynamic therapy and anti-vascular endothelial growth factor for polypoidal choroidal vasculopathy in an Indian population

    PubMed Central

    Sen, Parveen; Bhende, Muna; Sachidanandam, Ramya; Bansal, Nishat; Sharma, Tarun

    2016-01-01

    Aims: The aim was to study the efficacy of combined therapy with reduced-fluence photodynamic therapy (RFPDT) and intravitreal bevacizumab/ranibizumab from the Indian subcontinent. Settings and Design: This was a single-center, retrospective interventional study. Methods: Thirty-five eyes of 34 patients diagnosed with polypoidal choroidal vasculopathy were included. All the patients underwent RFPDT, followed by intravitreal bevacizumab/ranibizumab. Statistical Analysis Used: SPSS software, version 17.0 (SPSS Inc., Chicago, IL, USA) was used to compare the logarithm of the minimal angle of resolution visual acuity at presentation and final follow-up. P < 0.05 was considered statistically significant. Results: Regression of polyps after a single session of RFPDT was seen in five eyes; multiple sessions of treatment were required in thirty eyes. An average number of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections given were 4 ± 1.9 and average number of PDT sessions were 1.2 ± 0.5. Visual acuity improvement was seen in 21 (60%) eyes (P < 0.001), decrease in visual acuity was seen in 7 (20%) eyes (P = 0.016), and in 7 eyes (20%), vision remained stable. Regression of polypoidal lesions was seen in 80% of cases. No complications of massive subretinal hemorrhage or breakthrough vitreous hemorrhage were noted in our patients. The mean follow-up period was 18 months (range, 12–24 months). Conclusions: RFPDT with anti-VEGF is safe and effective treatment with polyp regression and vision improvement in 80% of cases, without any complication of subretinal hemorrhage/vitreous hemorrhage. PMID:28112132

  11. FSHD region gene 1 (FRG1) is crucial for angiogenesis linking FRG1 to facioscapulohumeral muscular dystrophy-associated vasculopathy.

    PubMed

    Wuebbles, Ryan D; Hanel, Meredith L; Jones, Peter L

    2009-01-01

    The genetic lesion that is diagnostic for facioscapulohumeral muscular dystrophy (FSHD) results in an epigenetic misregulation of gene expression, which ultimately leads to the disease pathology. FRG1 (FSHD region gene 1) is a leading candidate for a gene whose misexpression might lead to FSHD. Because FSHD pathology is most prominent in the musculature, most research and therapy efforts focus on muscle cells. Previously, using Xenopus development as a model, we showed that altering frg1 expression levels systemically leads to aberrant muscle development, illustrating the potential for aberrant FRG1 levels to disrupt the musculature. However, 50-75% of FSHD patients also exhibit retinal vasculopathy and FSHD muscles have increased levels of vascular- and endothelial-related FRG1 transcripts, illustrating an underlying vascular component to the disease. To date, no FSHD candidate gene has been proposed to affect the vasculature. Here, we focus on a role for FRG1 expression in the vasculature. We found that endogenous frg1 is expressed in both the developing and adult vasculature in Xenopus. Furthermore, expression of FRG1 was found to be essential for the development of the vasculature, as a knockdown of FRG1 resulted in decreased angiogenesis and reduced expression of the angiogenic regulator DAB2. Conversely, tadpoles subjected to frg1 overexpression displayed the pro-angiogenic phenotypes of increased blood vessel branching and dilation of blood vessels, and developed edemas, suggesting that their circulation was disrupted. Thus, the systemic upregulation of the FRG1 protein shows the potential for acquiring a disrupted vascular phenotype, providing the first link between a FSHD candidate gene and the vascular component of FSHD pathology. Overall, in conjunction with our previous analysis, we show that FRG1 overexpression is capable of disrupting both the musculature and vasculature, recapitulating the two most prominent features of FSHD.

  12. [The age-related macular degeneration as a vascular disease/part of systemic vasculopathy: contributions to its pathogenesis].

    PubMed

    Fischer, Tamás

    2015-03-01

    The wall of blood vessels including those in choroids may be harmed by several repeated and/or prolonged mechanical, physical, chemical, microbiological, immunologic, and genetic impacts (risk factors), which may trigger a protracted response, the so-called host defense response. As a consequence, pathological changes resulting in vascular injury (e. g. atherosclerosis, age-related macular degeneration) may be evolved. Risk factors can also act directly on the endothelium through an increased production of reactive oxygen species promoting an endothelial activation, which leads to endothelial dysfunction, the onset of vascular disease. Thus, endothelial dysfunction is a link between the harmful stimulus and vascular injury; any kind of harmful stimuli may trigger the defensive chain that results in inflammation that may lead to vascular injury. It has been shown that even early age-related macular degeneration is associated with the presence of diffuse arterial disease and patients with early age-related macular degeneration demonstrate signs of systemic and retinal vascular alterations. Chronic inflammation, a feature of AMD, is tightly linked to diseases associated with ED: AMD is accompanied by a general inflammatory response, in the form of complement system activation, similar to that observed in degenerative vascular diseases such as atherosclerosis. All these facts indicate that age-related macular degeneration may be a vascular disease (or part of a systemic vasculopathy). This recognition could have therapeutic implications because restoration of endothelial dysfunction may prevent the development or improve vascular disease resulting in prevention or improvement of age-related macular degeneration as well.

  13. Functional upregulation of the H2S/Cav3.2 channel pathway accelerates secretory function in neuroendocrine-differentiated human prostate cancer cells.

    PubMed

    Fukami, Kazuki; Sekiguchi, Fumiko; Yasukawa, Miku; Asano, Erina; Kasamatsu, Ryuji; Ueda, Mai; Yoshida, Shigeru; Kawabata, Atsufumi

    2015-10-01

    Neuroendocrine-differentiated prostate cancer cells may contribute to androgen-independent proliferation of surrounding cells through Ca(2+)-dependent secretion of mitogenic factors. Human prostate cancer LNCaP cells, when neuroendocrine-differentiated, overexpress Cav3.2 T-type Ca(2+) channels that contribute to Ca(2+)-dependent secretion. Given evidence for the acceleration of Cav3.2 activity by hydrogen sulfide (H2S), we examined the roles of the H2S/Cav3.2 pathway and then analyzed the molecular mechanisms of the Cav3.2 overexpression in neuroendocrine-differentiated LNCaP cells. LNCaP cells were differentiated by dibutyryl cyclic AMP. Protein levels and T-type Ca(2+) channel-dependent currents (T-currents) were measured by immunoblotting and whole-cell pacth-clamp technique, respectively. Spontaneous release of prostatic acid phosphatase (PAP) was monitored to evaluate secretory function. The differentiated LNCaP cells exhibited neurite outgrowth, androgen-independent proliferation and upregulation of mitogenic factors, and also showed elevation of Cav3.2 expression or T-currents. Expression of cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS), H2S-forming enzymes, and spontaneous secretion of PAP increased following the differentiation. The augmented T-currents were enhanced by H2S donors and suppressed by inhibitors of CSE, but not CBS. The PAP secretion was reduced by inhibition of CSE or T-type Ca(2+) channels. During differentiation, Egr-1 and REST, positive and negative transcriptional regulators for Cav3.2, were upregulated and downregulated, respectively, and Egr-1 knockdown prevented the Cav3.2 overexpression. Our data suggest that, in neuroendocrine-differentiated LNCaP cells, H2S formed by the upregulated CSE promotes the activity of the upregulated Cav3.2, leading to the elevated secretory functions. The overexpression of Cav3.2 appears to involve upregulation of Egr-1 and downregulation of REST.

  14. GDM-Induced Macrosomia Is Reversed by Cav-1 via AMPK-Mediated Fatty Acid Transport and GLUT1-Mediated Glucose Transport in Placenta

    PubMed Central

    Wang, Di; Yang, Ruirui; Sang, Hui; Han, Linlin; Zhu, Yuexia; Lu, Yanyan; Tan, Yeke; Shang, Zhanping

    2017-01-01

    Objective To investigate if the role of Cav-1 in GDM-induced macrosomia is through regulating AMPK signaling pathway in placenta. Methods We used diagnostic criteria of gestational diabetes mellitus (GDM) and macrosomia to separate and compare placental protein and mRNA levels from GDM with macrosomia group (GDMM), GDM with normal birth weight group (GDMN) and normal glucose tolerance (NGT) with normal birth weight group (CON). Western blotting was performed to examine differentially expressed proteins of caveolin-1 (Cav-1) and Adenosine monophosphate-activated protein kinase (AMPK) signaling pathway related proteins, including phosphorylated-AMPKα(Thr172), AMPKα, phosphorylated-Acetyl-CoA carboxylase(Ser79) (p-ACC(Ser79)), ACC and glucose transporter 1 (GLUT1) in placenta between the three groups. The mRNA levels of Cav-1, AMPKα, ACC and GLUT1 in placenta were measured by real time-PCR. Results In the GDMM placenta group, both protein and mRNA levels of Cav-1 were down-regulated, while GLUT1 was up-regulated; the phosphorylation and mRNA levels of ACC and AMPKα were decreased, but total ACC protein levels were increased compared to both the GDMN (p<0.05) and CON groups (p<0.05). In GDMM placenta group, there was a significant negative correlation observed between neonatal birth weight (NBW) and protein expression levels of Cav-1, p-ACC(Ser79) and p-AMPKα(Thr172) (p<0.05), while positive relationship with ACC and GLUT1 protein levels. Besides, in GDMM group placental mRNA levels, NBW had a positive correlation with GLUT1 (p<0.05), while negative with Cav-1, AMPKα and ACC expression (p<0.05). Cav-1 protein expression was positively associated with p-AMPK and p-ACC (p<0.05), and negatively associated with GLUT1 (p<0.05). Interestingly, p-AMPK protein expression was closely related to p-ACC (p<0.05), but not with GLUT1. Conclusion GDM-induced macrosomias have more severe inhibition of Cav-1 expression in placenta. Cav-1 is associated with placental glucose and

  15. A Novel CaV1.2 N Terminus Expressed in Smooth Muscle Cells of Resistance Size Arteries Modifies Channel Regulation by Auxiliary Subunits*S

    PubMed Central

    Cheng, Xiaoyang; Liu, Jianxi; Asuncion-Chin, Maria; Blaskova, Eva; Bannister, John P.; Dopico, Alejandro M.; Jaggar, Jonathan H.

    2008-01-01

    Voltage-dependent L-type Ca2+ (CaV1.2) channels are the principal Ca2+ entry pathway in arterial myocytes. CaV1.2 channels regulate multiple vascular functions and are implicated in the pathogenesis of human disease, including hypertension. However, the molecular identity of CaV1.2 channels expressed in myocytes of myogenic arteries that regulate vascular pressure and blood flow is unknown. Here, we cloned CaV1.2 subunits from resistance size cerebral arteries and demonstrate that myocytes contain a novel, cysteine rich N terminus that is derived from exon 1 (termed “exon 1c”), which is located within CACNA1C, the CaV1.2 gene. Quantitative PCR revealed that exon 1c was predominant in arterial myocytes, but rare in cardiac myocytes, where exon 1a prevailed. When co-expressed with α2δ subunits, CaV1.2 channels containing the novel exon 1c-derived N terminus exhibited: 1) smaller whole cell current density, 2) more negative voltages of half activation (V1/2,act) and half-inactivation (V1/2,inact), and 3) reduced plasma membrane insertion, when compared with channels containing exon 1b. β1b and β2a subunits caused negative shifts in the V1/2,act and V1/2,inact of exon 1b-containing CaV1.2α1/α2δ currents that were larger than those in exon 1c-containing CaV1.2α1/α2δ currents. In contrast, β3 similarly shifted V1/2,act and V1/2,inact of currents generated by exon 1b- and exon 1c-containing channels. β subunits isoform-dependent differences in current inactivation rates were also detected between N-terminal variants. Data indicate that through novel alternative splicing at exon 1, the CaV1.2 N terminus modifies regulation by auxiliary subunits. The novel exon 1c should generate distinct voltage-dependent Ca2+ entry in arterial myocytes, resulting in tissue-specific Ca2+ signaling. PMID:17699517

  16. Anaplastic Ependymoma in a Child With Sickle Cell Anemia: A Case Report Highlighting Treatment Challenges for Young Children With Central Nervous System Tumors and Underlying Vasculopathy.

    PubMed

    Crotty, Erin E; Meier, Emily R; Wells, Elizabeth M; Hwang, Eugene I; Packer, Roger J

    2016-03-01

    A 3-year-old boy with sickle cell anemia (SCA) presented with progressive daily emesis and was found to have an anaplastic ependymoma. Radiation therapy and chemotherapy are usually employed after subtotal resections of anaplastic ependymomas, although the benefits from chemotherapy are unclear. To mitigate the risks of adjuvant treatment in this patient at risk for SCA-associated vasculopathy, renal impairment, and other end-organ damage, proton beam irradiation without chemotherapy was chosen. Scheduled packed red blood cell transfusions were instituted to maintain sickle hemoglobin levels less than 30%. This case highlights treatment complexities for malignant brain tumors in patients predisposed to treatment-related adverse effects.

  17. Phosphorylation of Ser1928 mediates the enhanced activity of the L-type Ca2+ channel Cav1.2 by the β2-adrenergic receptor in neurons

    PubMed Central

    Qian, Hai; Patriarchi, Tommaso; Price, Jennifer L.; Matt, Lucas; Lee, Boram; Nieves-Cintrón, Madeline; Buonarati, Olivia R.; Chowdhury, Dhrubajyoti; Nanou, Evanthia; Nystoriak, Matthew A.; Catterall, William A.; Poomvanicha, Montatip; Hofmann, Franz; Navedo, Manuel F.; Hell, Johannes W.

    2017-01-01

    The L-type Ca2+ channel Cav1.2 controls multiple functions throughout the body including heart rate and neuronal excitability. It is a key mediator of fight-or-flight stress responses triggered by a signaling pathway involving β-adrenergic receptors (βARs), cyclic adenosine monophosphate (cAMP), and protein kinase A (PKA). PKA readily phosphorylates Ser1928 in Cav1.2 in vitro and in vivo, including in rodents and humans. However, S1928A knock-in (KI) mice have normal PKA-mediated L-type channel regulation in the heart, indicating that Ser1928 is not required for regulation of cardiac Cav1.2 by PKA in this tissue. We report that augmentation of L-type currents by PKA in neurons was absent in S1928A KI mice. Furthermore, S1928A KI mice failed to induce long-term potentiation in response to prolonged theta-tetanus (PTT-LTP), a form of synaptic plasticity that requires Cav1.2 and enhancement of its activity by the β2-adrenergic receptor (β2AR)–cAMP–PKA cascade. Thus, there is an unexpected dichotomy in the control of Cav1.2 by PKA in cardiomyocytes and hippocampal neurons. PMID:28119465

  18. Gating charges per channel of Ca(V)2.2 channels are modified by G protein activation in rat sympathetic neurons.

    PubMed

    Rebolledo-Antúnez, Santiago; Farías, José M; Arenas, Isabel; García, David E

    2009-06-01

    It has been suggested that voltage-dependent G protein modulation of Ca(V)2.2 channels is carried out at closed states of the channel. Our purpose was to estimate the number of gating charges of Ca(V)2.2 channel in control and G protein-modulated conditions. By using a Cole-Moore protocol we observed a significant delay in Ca(V)2.2 channel activation according to a transit of the channel through a series of closed states before channel opening. If G protein voltage-dependent modulation were carried out at these closed states, then we would have expected a greater Cole-Moore lag in the presence of a neurotransmitter. This prediction was confirmed for noradrenaline, while no change was observed in the presence of angiotensin II, a voltage-insensitive G protein modulator. We used the limiting slope method for calculation of the gating charge per channel. Effective charge z was 6.32+/-0.65 for Ca(V)2.2 channels in unregulated conditions, while GTPgammaS reduced elementary charge by approximately 4 e(0). Accordingly, increased concentration of noradrenaline induced a gradual decrease on z, indicating that this decrement was due to a G protein voltage-sensitive modulation. This paper shows for the first time a significant and reversible decrease in charge transfer of Ca(V)2.2 channels under G protein modulation, which might depend on the activated G protein inhibitory pathway.

  19. Molecular simulations study of novel 1,4-dihydropyridines derivatives with a high selectivity for Cav3.1 calcium channel

    PubMed Central

    Liu, Xiaoguang; Yu, Hui; Zhao, Xi; Huang, Xu-Ri

    2015-01-01

    1,4-Dihydropyridines (DHPs) have been developed to treat hypertension, angina, and nerve system disease. They are thought to mainly target the L-type calcium channels, but low selectivity prompts them to block Cav1.2 and Cav3.1 channels simultaneously. Recently, some novel DHPs with different hydrophobic groups have been synthesized and among them M12 has a higher selectivity for Cav3.1. However, the structural information about Cav3.1-DHPs complexes is not available in the experiment. Thus, we combined homology modeling, molecular docking, molecular dynamics simulations, and binding free energy calculations to quantitatively elucidate the inhibition mechanism of DHPs. The calculated results indicate that our model is in excellent agreement with experimental results. On the basis of conformational analysis, we identify the main interactions between DHPs and calcium channels and further elaborate on the different selectivity of ligands from the micro perspective. In conjunction with energy distribution, we propose that the binding sites of Cav3.1-DHPs is characterized by several interspersed hydrophobic amino acid residues on the IIIS6 and IVS6 segments. We also speculate the favorable function groups on prospective DHPs. Besides, our model provides important information for further mutagenesis experiments. PMID:26256672

  20. Structural basis for the differential effects of CaBP1 and calmodulin on CaV1.2 calcium-dependent inactivation

    PubMed Central

    Findeisen, Felix; Minor, Daniel L.

    2010-01-01

    Calcium-binding protein 1 (CaBP1), a calmodulin (CaM) homolog, endows certain voltage-gated calcium channels (CaVs) with unusual properties. CaBP1 inhibits CaV1.2 calcium-dependent inactivation (CDI) and introduces calcium-dependent facilitation (CDF). Here, we show that the ability of CaBP1 to inhibit CaV1.2 CDI and induce CDF arises from interaction between the CaBP1 N-lobe and interlobe linker residue Glu94. Unlike CaM, where functional EF hands are essential for channel modulation, CDI inhibition does not require functional CaBP1 EF-hands. Furthermore, CaBP1-mediated CDF has different molecular requirements than CaM-mediated CDF. Overall, the data show that CaBP1 comprises two structural modules having separate functions: similar to CaM, the CaBP1 C-lobe serves as a high-affinity anchor that binds the CaV1.2 IQ domain at a site that overlaps with the Ca2+/CaM C-lobe site, whereas the N-lobe/linker module houses the elements required for channel modulation. Discovery of this division provides the framework for understanding how CaBP1 regulates CaVs. PMID:21134641

  1. Amyloid Precursor Protein Regulates Cav1.2 L-type Calcium Channel Levels and Function to Influence GABAergic Short-term Plasticity

    PubMed Central

    Yang, Li; Wang, Zilai; Wang, Baiping; Justice, Nicholas J.; Zheng, Hui

    2010-01-01

    Amyloid precursor protein (APP) has been strongly implicated in the pathogenesis of Alzheimer’s disease (AD). Although impaired synaptic function is believed to be an early and causative event in AD, how APP physiologically regulates synaptic properties remains poorly understood. Here, we report a critical role for APP in the regulation of L-type calcium channels (LTCC) in GABAergic inhibitory neurons in striatum and hippocampus. APP deletion in mice leads to an increase in the levels of Cav1.2, the pore-forming subunit of LTCCs, and subsequent increases in GABAergic calcium currents (ICa 2+) that can be reversed by re-introduction of APP. Upregulated levels of Cav1.2 result in reduced GABAergic paired-pulse inhibition (PPI) and increased GABAergic post-tetanic potentiation (PTP) in both striatal and hippocampal neurons, indicating that APP modulates synaptic properties of GABAergic neurons by regulating Cav1.2. Furthermore, APP physically interacts with Cav1.2, suggesting a mechanism in which loss of APP leads to an inappropriate accumulation and aberrant activity of Cav1.2. These results provide a direct link between APP and calcium signaling and might help explain how altered APP regulation leads to changes in synaptic function that occur with AD. PMID:20016080

  2. Molecular simulations study of novel 1,4-dihydropyridines derivatives with a high selectivity for Cav3.1 calcium channel.

    PubMed

    Liu, Xiaoguang; Yu, Hui; Zhao, Xi; Huang, Xu-Ri

    2015-11-01

    1,4-Dihydropyridines (DHPs) have been developed to treat hypertension, angina, and nerve system disease. They are thought to mainly target the L-type calcium channels, but low selectivity prompts them to block Cav1.2 and Cav3.1 channels simultaneously. Recently, some novel DHPs with different hydrophobic groups have been synthesized and among them M12 has a higher selectivity for Cav3.1. However, the structural information about Cav3.1-DHPs complexes is not available in the experiment. Thus, we combined homology modeling, molecular docking, molecular dynamics simulations, and binding free energy calculations to quantitatively elucidate the inhibition mechanism of DHPs. The calculated results indicate that our model is in excellent agreement with experimental results. On the basis of conformational analysis, we identify the main interactions between DHPs and calcium channels and further elaborate on the different selectivity of ligands from the micro perspective. In conjunction with energy distribution, we propose that the binding sites of Cav3.1-DHPs is characterized by several interspersed hydrophobic amino acid residues on the IIIS6 and IVS6 segments. We also speculate the favorable function groups on prospective DHPs. Besides, our model provides important information for further mutagenesis experiments.

  3. Investigation of biological activity of polar extracts isolated from Phlomis crinita Cav ssp. mauritanica Munby.

    PubMed

    Limem-Ben Amor, Ilef; Skandrani, Ines; Boubaker, Jihed; Ben Sghaïer, Mohamed; Neffati, Aicha; Bhouri, Wissem; Bouhlel, Ines; Chouchane, Nabil; Kilani, Soumaya; Guedon, Emmanuel; Ghoul, Mohamed; Ghedira, Kamel; Chekir-Ghedira, Leila

    2009-01-01

    The lyophilized infusion, the methanol, the ethyl acetate, and the total oligomer flavonoid (TOF)-enriched extracts prepared from the dried leaves of Phlomis crinita Cav. ssp. mauritanica Munby were investigated for the contents of flavonoids, tannins, coumarines and steroids. Antibacterial activity was investigated toward five bacterial strains. An inhibitory effect was observed against Staphyllococcus aureus and Enterococcus feacalis, and the minimal inhibitory concentrations ranged from 2.5 to 5 mg/mL of extract. The tested extracts exhibit an important free radical scavenging activity toward the 1,1-diphenyl 2-picrylhydrazyl (DPPH) free radical; with IC(50) values of 30.5, 6, 32, and 31.5 microg/mL, respectively, in the presence of lyophilized infusion, the TOF, the methanol, and the ethyl acetate extracts. Genotoxic and antigenotoxic properties of the different extracts were studied by using the SOS chromotest with Escherichia coli PQ37. The lyophilized infusion and TOF extracts obtained from P. crinita ssp. mauritanica showed no genotoxicity, whereas methanol and ethyl acetate extracts are considered as marginally genotoxic. On the other hand, we showed that each extract inhibited the mutagenicity induced by aflatoxin B1 (AFB1) (10 microg/assay) and nifuroxazide (NF) (10 microg/assay). The ethyl acetate extract showed the strongest level of protection toward the genotoxicity induced by both directly and indirectly genotoxic NF and AFB1. These tests proved that the lyophilized infusion possesses an antiradical activity likewise, it showed no genotoxic effect; that is why we choose this extract to assess its antiulcerogenic activity by using an ethanol-induced ulcerogenesis model in the rat. This test demonstrates that 300 mg/kg of a P. crinita ssp. mauritanica lyophilized infusion was more effective than the reference compound, cimetidine.

  4. Antidepressant-like effect of Tagetes lucida Cav. extract in rats: involvement of the serotonergic system.

    PubMed

    Gabriela, Guadarrama-Cruz; Javier, Alarcón-Aguilar Francisco; Elisa, Vega-Avila; Gonzalo, Vázquez-Palacios; Herlinda, Bonilla-Jaime

    2012-01-01

    It has been demonstrated that the decoction of the aerial parts of Tagetes lucida Cav. produces an antidepressant effect during the forced swimming test (FST) in rats. The aim of this study was to evaluate the effect of different organic extracts and one aqueous extract of the aerial parts of T. lucida on the FST. In addition, the possible involvement of the serotonergic system in the antidepressant-like effect of T. lucida in the FST was evaluated, as was its potential toxicological effect. The different extracts of T. lucida (methanol, hexane, dichloromethane and aqueous, 10 and 50 mg/kg), as well as fluoxetine (FLX, 5 mg/kg), were administered per os (p.o.) to rats for 14 days. All animals were subjected to the FST. Only the aqueous extract of T. lucida at a dose of 50 mg/kg significantly reduced immobility behavior and increased swimming in the FST, similar to FLX. Later, the aqueous extract of T. lucida (50mg/kg) was administered for 1, 7 and 14 days. An antidepressant effect was observed after 7 days of treatment. To evaluate the participation of the serotoninergic system, the animals were pretreated with PCPA, an inhibitor of serotonin synthesis (100 mg/kg/day for 4 consecutive days). The animals were treated with the aqueous extract of T. lucida (50 mg/kg) and FLX (5 mg/kg) 24 h after the final injection and were then subjected to the FST. Pretreatment with PCPA inhibited the antidepressant effect of both T. lucida and FLX. Finally, T. lucida was administered p.o. and intraperitoneal route to evaluate its acute toxicological effect. The aqueous extract of T. lucida, administered p.o., did not produce lethality or any significant changes in behavior. In conclusion, the aqueous extract of T. lucida manifested an antidepressant-like effect in the FST mediated by the serotonergic system, with no adverse effects when administered p.o.

  5. Management of Liver Allograft Trauma Resulting in Massive Subcapsular Hematoma After Living Donor Liver Transplantation: Can We Salvage the Liver Allograft?

    PubMed

    Hsu, Shih-Chao; Thorat, Ashok; Poon, Kin-Shing; Yeh, Chun-Chieh; Chen, Te-Hung; Yang, Horng-Ren; Jeng, Long-Bin

    2017-01-05

    BACKGROUND Liver allograft trauma resulting in subcapsular hematoma after living donor liver transplantation (LDLT), although rare, is a life-threatening condition and requires prompt management to avoid any catastrophe. Herein we describe our successful experience in dealing with liver allograft hematoma that developed in the post-operative period after LDLT. MATERIAL AND METHODS From January 2002 to May 2015, a total of 616 recipients underwent LDLT at our institute. The intra-operative and postoperative records of these patients were analyzed to study the cases of liver allograft hematoma. Four patients (n=4) who developed liver allograft subcapsular hematoma during the intra-operative and post-operative periods were included in study. The outcomes of these patients were studied after the administration of the medical, surgical, or combined modalities of treatment. RESULTS Out of 616 LDLT recipients, 4 (0.64%) developed subcapsular hematoma. Patients were managed by a stepwise approach: Initial non-operative management with transarterial embolization (if extravasation of the contrast was noticed during imaging studies) was performed (n=1). Three patients developed hemodynamic instability with signs of hematoma rupture and were successfully treated by surgical exploration. CONCLUSIONS Timely diagnosis and suitable management can successfully salvage a liver allograft even in the presence of massive subcapsular hematoma. Our emphasis is on perihepatic packing rather than open surgical drainage if exploration is required, which can achieve a 100% success rate.

  6. Electrophysiological characterization of activation state-dependent Cav2 channel antagonist TROX-1 in spinal nerve injured rats

    PubMed Central

    Patel, R.; Rutten, K.; Valdor, M.; Schiene, K.; Wigge, S.; Schunk, S.; Damann, N.; Christoph, T.; Dickenson, A.H.

    2015-01-01

    Prialt, a synthetic version of Cav2.2 antagonist ω-conotoxin MVIIA derived from Conus magus, is the first clinically approved voltage-gated calcium channel blocker for refractory chronic pain. However, due to the narrow therapeutic window and considerable side effects associated with systemic dosing, Prialt is only administered intrathecally. N-triazole oxindole (TROX-1) is a novel use-dependent and activation state-selective small-molecule inhibitor of Cav2.1, 2.2 and 2.3 calcium channels designed to overcome the limitations of Prialt. We have examined the neurophysiological and behavioral effects of blocking calcium channels with TROX-1. In vitro, TROX-1, in contrast to state-independent antagonist Prialt, preferentially inhibits Cav2.2 currents in rat dorsal root ganglia (DRG) neurons under depolarized conditions. In vivo electrophysiology was performed to record from deep dorsal horn lamina V/VI wide dynamic range neurons in non-sentient spinal nerve-ligated (SNL) and sham-operated rats. In SNL rats, spinal neurons exhibited reduced responses to innocuous and noxious punctate mechanical stimulation of the receptive field following subcutaneous administration of TROX-1, an effect that was absent in sham-operated animals. No effect was observed on neuronal responses evoked by dynamic brushing, heat or cold stimulation in SNL or sham rats. The wind-up response of spinal neurons following repeated electrical stimulation of the receptive field was also unaffected. Spinally applied TROX-1 dose dependently inhibited mechanically evoked neuronal responses in SNL but not sham-operated rats, consistent with behavioral observations. This study confirms the pathological state-dependent actions of TROX-1 through a likely spinal mechanism and reveals a modality selective change in calcium channel function following nerve injury. PMID:25839150

  7. Electrophysiological characterization of activation state-dependent Ca(v)2 channel antagonist TROX-1 in spinal nerve injured rats.

    PubMed

    Patel, R; Rutten, K; Valdor, M; Schiene, K; Wigge, S; Schunk, S; Damann, N; Christoph, T; Dickenson, A H

    2015-06-25

    Prialt, a synthetic version of Ca(v)2.2 antagonist ω-conotoxin MVIIA derived from Conus magus, is the first clinically approved voltage-gated calcium channel blocker for refractory chronic pain. However, due to the narrow therapeutic window and considerable side effects associated with systemic dosing, Prialt is only administered intrathecally. N-triazole oxindole (TROX-1) is a novel use-dependent and activation state-selective small-molecule inhibitor of Ca(v)2.1, 2.2 and 2.3 calcium channels designed to overcome the limitations of Prialt. We have examined the neurophysiological and behavioral effects of blocking calcium channels with TROX-1. In vitro, TROX-1, in contrast to state-independent antagonist Prialt, preferentially inhibits Ca(v)2.2 currents in rat dorsal root ganglia (DRG) neurons under depolarized conditions. In vivo electrophysiology was performed to record from deep dorsal horn lamina V/VI wide dynamic range neurons in non-sentient spinal nerve-ligated (SNL) and sham-operated rats. In SNL rats, spinal neurons exhibited reduced responses to innocuous and noxious punctate mechanical stimulation of the receptive field following subcutaneous administration of TROX-1, an effect that was absent in sham-operated animals. No effect was observed on neuronal responses evoked by dynamic brushing, heat or cold stimulation in SNL or sham rats. The wind-up response of spinal neurons following repeated electrical stimulation of the receptive field was also unaffected. Spinally applied TROX-1 dose dependently inhibited mechanically evoked neuronal responses in SNL but not sham-operated rats, consistent with behavioral observations. This study confirms the pathological state-dependent actions of TROX-1 through a likely spinal mechanism and reveals a modality selective change in calcium channel function following nerve injury.

  8. Mechanisms of inhibition of CaV3.1 T-type calcium current by aliphatic alcohols

    PubMed Central

    Eckle, Veit-Simon; Todorovic, Slobodan M

    2010-01-01

    Many aliphatic alcohols modulate activity of various ion channels involved in sensory processing and also exhibit anesthetic capacity in vivo. Although the interaction of one such compound, 1-octanol (octanol) with different T-type calcium channels (T-channels) has been described, the mechanisms of current modulation and its functional significance are not well studied. Using patch-clamp technique, we investigated the mechanisms of inhibition of T-currents by a series of aliphatic alcohols in recombinant human CaV3.1 (α1G) T-channel isoform expressed in human embryonic kidney (HEK) 293 cells and thalamocortical (TC) relay neurons in brain slices of young rats. Octanol, 1-heptanol (heptanol) and 1-hexanol (hexanol) inhibited the recombinant CaV3.1 currents in concentration-dependent manner yielding IC50 values of 362 µM, 1063 µM and 3167 µM, respectively. Octanol similarly inhibited native thalamic CaV3.1 T-currents with an IC50 of 287 µM and diminished burst firing without significant effect on passive membrane properties of these neurons. Inhibitory effect of octanol on T-currents in both native and recombinant cells was accompanied with accelerated macroscopic inactivation kinetics and hyperpolarizing shift in the steady-state inactivation curve. Additionally, octanol induced a depolarizing shift in steady-state activation curves of T-current in TC neurons. Surprisingly, the recovery from fast inactivation at hyperpolarized membrane potentials was accelerated by octanol up three-fold in native but not recombinant channels. Given the importance of thalamocortical pathways in providing sleep, arousal, and anesthetic states, modulation of thalamic T-currents may at least contribute to the pharmacological effects of aliphatic alcohols. PMID:20363234

  9. Hydrogen sulfide-induced itch requires activation of Cav3.2 T-type calcium channel in mice

    PubMed Central

    Wang, Xue-Long; Tian, Bin; Huang, Ya; Peng, Xiao-Yan; Chen, Li-Hua; Li, Jun-Cheng; Liu, Tong

    2015-01-01

    The contributions of gasotransmitters to itch sensation are largely unknown. In this study, we aimed to investigate the roles of hydrogen sulfide (H2S), a ubiquitous gasotransmitter, in itch signaling. We found that intradermal injection of H2S donors NaHS or Na2S, but not GYY4137 (a slow-releasing H2S donor), dose-dependently induced scratching behavior in a μ-opioid receptor-dependent and histamine-independent manner in mice. Interestingly, NaHS induced itch via unique mechanisms that involved capsaicin-insensitive A-fibers, but not TRPV1-expressing C-fibers that are traditionally considered for mediating itch, revealed by depletion of TRPV1-expressing C-fibers by systemic resiniferatoxin treatment. Moreover, local application of capsaizapine (TRPV1 blocker) or HC-030031 (TRPA1 blocker) had no effects on NaHS-evoked scratching. Strikingly, pharmacological blockade and silencing of Cav3.2 T-type calcium channel by mibefradil, ascorbic acid, zinc chloride or Cav3.2 siRNA dramatically decreased NaHS-evoked scratching. NaHS induced robust alloknesis (touch-evoked itch), which was inhibited by T-type calcium channels blocker mibefradil. Compound 48/80-induced itch was enhanced by an endogenous precursor of H2S (L-cysteine) but attenuated by inhibitors of H2S-producing enzymes cystathionine γ-lyase and cystathionine β-synthase. These results indicated that H2S, as a novel nonhistaminergic itch mediator, may activates Cav3.2 T-type calcium channel, probably located at A-fibers, to induce scratching and alloknesis in mice. PMID:26602811

  10. Disinfection of human skin allografts in tissue banking: a systematic review report.

    PubMed

    Johnston, C; Callum, J; Mohr, J; Duong, A; Garibaldi, A; Simunovic, N; Ayeni, O R

    2016-12-01

    The use of skin allografts to temporarily replace lost or damaged skin is practiced worldwide. Naturally occurring contamination can be present on skin or can be introduced at recovery or during processing. This contamination can pose a threat to allograft recipients. Bacterial culture and disinfection of allografts are mandated, but the specific practices and methodologies are not dictated by standards. A systematic review of literature from three databases found 12 research articles that evaluated bioburden reduction processes of skin grafts. The use of broad spectrum antibiotics and antifungal agents was the most frequently identified disinfection method reported demonstrating reductions in contamination rates. It was determined that the greatest reduction in the skin allograft contamination rates utilized 0.1 % peracetic acid or 25 kGy of gamma irradiation at lower temperatures.

  11. Platelet deposition in rat heart allografts and the effect of a thromboxane receptor antagonist

    SciTech Connect

    Foegh, M.L.; Khirabadi, B.S.; Ramwell, P.W.

    1986-07-01

    The effect of a thromboxane antagonist, L640,035 on platelet deposition in heart allografts was studied. Twenty Lewis rats received heterotopic allografts from Lewis x Brown-Norway F1 hybrid. All recipients received azathioprine (5 mg/kg/day). The rats were divided into three groups. Groups II and III were also treated daily with either the vehicle for L640,035 or L640,035 respectively. Syngeneic indium-111-labeled platelet deposition was determined in the allograft and the native heart at 6, 9, and 13 days after transplantation; group III was studied on the sixth and ninth day only. A rapidly increasing platelet deposition was seen in allografts from rats given azathioprine; whereas the thromboxane antagonist prevented the increase in platelet deposition on the ninth day.

  12. Chronic Achilles Tendon Rupture Treated with Allograft: A Case Report.

    PubMed

    Restuccia, Giuseppe; Lippi, Alessandro; Casella, Francesco; Citarelli, Carmine; Sacchetti, Federico; Benifei, Maurizio

    2017-02-07

    In clinical practice, chronic Achilles tendon ruptures are uncommon. Usually, these lesions are discovered four to six weeks after injuries. More frequently, Achilles tendon ruptures are acute and treated with tendon sutures.1 Many surgical techniques are available to treat chronic lesions such as sutures or V-Y elongation with or without augments.2-3 Our case is about a chronic Achilles tendon rupture discovered two years after injury. Our patient came to our attention with a 6 cm tendon gap. We performed tendon repair with cadaver allograft. After four years of follow-up, our patient has a complete functional recovery and he can normally perform daily and working tasks without pain.

  13. Rational clinical trial design for antibody mediated renal allograft injury

    PubMed Central

    Sandal, Shaifali; Zand, Martin S.

    2015-01-01

    Antibody mediated renal allograft rejection is a significant cause of acute and chronic graft loss. Recent work has revealed that AMR is a complex processes, involving B and plasma cells, donor-specific antibodies, complement, vascular endothelial cells, NK cells, Fc receptors, cytokines and chemokines. These insights have led to the development of numerous new therapies, and adaptation of others originally developed for treatment of hemetologic malignancies, autoimmune and complement mediated conditions. Here we review emerging insights into the pathophysiology of AMR as well as current and emerging therapies for both acute and chronic AMR. Finally, we discuss rational clinical trial design in light of antibody and B cell immunobiology, as well as appropriate efficacy metrics to identify robust protocols and therapeutic agents. PMID:25553476

  14. Renal allograft glomerulopathy and the value of immunohistochemistry.

    PubMed

    Freese, P M; Svalander, C T; Mölne, J; Nyberg, G

    2004-10-01

    Studies of late renal allograft biopsies focus on chronic damage investigated by light microscopy (LM). We evaluated the use of immunohistochemistry (IH) as applied in the routine study of transplant glomerulopathies. Among renal transplants in 1985 - 1997, 129 were identified where a graft biopsy had been obtained 6 months or more after transplantation, studied by LM and IH and the original renal disease was known. IH results were evaluated in relation to glomerular LM findings and the original diagnosis. The risk of graft loss in relation to recurrent and de novo glomerulopathy was evaluated. By LM, 69 biopsies (53%) showed glomerulopathy, mesangial sclerosis only in 26, proliferative changes in 15, membranous in 15 and combined membranous and proliferative in 13. By IH, 46 biopsies (36%) stained positive with IgM and/or complement only and 24 with immune complexes including IgA and/or IgG. Seven biopsies (5.4%) showed glomerular disease by IH in spite of normal LM. Recurrence was diagnosed in 22 grafts; 12 had IgA nephropathy, 3 had SLE, 6 other immune complex nephritides and 1 systemic vasculitis. Twenty-eight biopsies (22%) with proliferative and/or membranous glomerulopathy lacked clear connection to the original renal disorder. More than half of these had deposits of IgM and C3 only. The further graft survival was significantly reduced in the presence of de novo glomerulopathy by LM, relative risk 2.0 (confidence interval 1.1 - 3.8) in a Cox-proportional hazards analysis also including serum creatinine and Banff chronic allograft nephropathy (CAN) grade, p = 0.03. In conclusion, transplant glomerulopathy should be separated from recurrence. De novo glomerulopathy is frequent and ominous.

  15. Symptomatic Respiratory Virus Infection and Chronic Lung Allograft Dysfunction

    PubMed Central

    Fisher, Cynthia E.; Preiksaitis, Carl M.; Lease, Erika D.; Edelman, Jeffrey; Kirby, Katharine A.; Leisenring, Wendy M.; Raghu, Ganesh; Boeckh, Michael; Limaye, Ajit P.

    2016-01-01

    Background. Chronic lung allograft dysfunction (CLAD) is a major cause of allograft loss post-lung transplantation. Prior studies have examined the association between respiratory virus infection (RVI) and CLAD were limited by older diagnostic techniques, study design, and case numbers. We examined the association between symptomatic RVI and CLAD using modern diagnostic techniques in a large contemporary cohort of lung transplant recipients (LTRs). Methods. We retrospectively assessed clinical variables including acute rejection, cytomegalovirus pneumonia, upper and lower RVI, and the primary endpoint of CLAD (determined by 2 independent reviewers) in 250 LTRs in a single university transplantation program. Univariate and multivariate Cox models were used to analyze the relationship between RVI and CLAD in a time-dependent manner, incorporating different periods of risk following RVI diagnosis. Results. Fifty patients (20%) were diagnosed with CLAD at a median of 95 weeks post-transplantation, and 79 (32%) had 114 episodes of RVI. In multivariate analysis, rejection and RVI were independently associated with CLAD (adjusted hazard ratio [95% confidence interval]) 2.2 (1.2–3.9), P = .01 and 1.9 (1.1–3.5), P = .03, respectively. The association of RVI with CLAD was stronger the more proximate the RVI episode: 4.8 (1.9–11.6), P < .01; 3.4 (1.5–7.5), P < .01; and 2.4 (1.2–5.0), P = .02 in multivariate analysis for 3, 6, and 12 months following RVI, respectively. Conclusions. Symptomatic RVI is independently associated with development of CLAD, with increased risk at shorter time periods following RVI. Prospective studies to characterize the virologic determinants of CLAD and define the underlying mechanisms are warranted. PMID:26565010

  16. Effects of growth hormone administration in pediatric renal allograft recipients.

    PubMed

    Bartosh, S; Kaiser, B; Rezvani, I; Polinsky, M; Schulman, S; Palmer, J; Baluarte, H J

    1992-01-01

    The efficacy of recombinant human growth hormone (rGH) was assessed in five pediatric allograft recipients with severe growth retardation despite successful renal transplants. rGH 0.05 mg/kg per dose was given six times weekly by subcutaneous injection to five prepubertal children (mean age 15.2 +/- 2.0 years) all of whom had bone ages less than or equal to 12 years (10.0 +/- 1.4 years), a height standard deviation score of less than -2.5 (-4.9 +/- 1.5), no evidence of catch-up growth, a calculated glomerular filtration rate (GFR) of more than 40 ml/min per 1.73 m2 (51 +/- 6.8 ml/min per 1.73 m2), and stable renal function on alternate-day prednisone (16.7 +/- 2.6 mg/m2 per dose). Growth hormone profiles were abnormal in all children before treatment. rGH administration led to a significant increase in both growth rate (3.5 +/- 1.6 cm/year pre therapy, 8.5 +/- 1.4 cm/year post therapy, P less than 0.001) and percentage of expected growth velocity for bone age (67 +/- 31% pre therapy, 163 +/- 27% post therapy, P less than 0.001) with evidence of true catch-up growth. During the study period, three children had the appearance of secondary sexual characteristics, and one had premature advancement of his bone age. GFR decreased in three children, and in one rGH was discontinued due to a steady rise in serum creatinine. No significant changes were seen in serum calcium, phosphorus, cholesterol, triglycerides, glucose, or thyroid function, although a significant increase in alkaline phosphatase was found. In summary, growth-retarded pediatric renal allograft recipients may have abnormal endogenous GH production and respond favorably to rGH.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Is Duplex-Ultrasound a useful tool in defining rejection episodes in composite tissue allograft transplants?

    PubMed

    Loizides, Alexander; Kronberger, Irmgard-Elisabeth; Plaikner, Michaela; Gruber, Hannes

    2015-12-01

    Immunologic reactions in transplanted organs are in more or less all allograft patients detectable: clear parameters exist as e.g. in renal transplants where the clearance power reduces by rejection. On the contrary, in composite tissue allografts clear and objective indicators stating a rejection episode lack. We present the case of a hand-transplanted subject with signs of acute transplant rejection diagnosed by means of Duplex Ultrasound and confirmed by biopsy.

  18. Modulating Wnt Signaling Pathway to Enhance Allograft Integration in Orthopaedic Trauma Treatment

    DTIC Science & Technology

    2012-10-01

    neutralizing the LRP5/Wnt pathway inhibitors Sost or DKK1 with monoclonal antibodies will enhance allograft integration to the host bone. The proposed work in...endpoints. Aim 2: Determine the effect of modulating the LRP-5/Wnt pathway with anti- Dkk1 monoclonal antibody on allograft incorporation in a rat...time point, saline/anti-Sost/Anti- Dkk1 ; N=16 each treatment) have been treated, samples harvested and banked for analysis. In vivo radiographs as

  19. Iliac Crest Bone Graft versus Local Autograft or Allograft for Lumbar Spinal Fusion: A Systematic Review

    PubMed Central

    Tuchman, Alexander; Brodke, Darrel S.; Youssef, Jim A.; Meisel, Hans-Jörg; Dettori, Joseph R.; Park, Jong-Beom; Yoon, S. Tim; Wang, Jeffrey C.

    2016-01-01

    Study Design  Systematic review. Objective  To compare the effectiveness and safety between iliac crest bone graft (ICBG) and local autologous bone and allograft in the lumbar spine. Methods  A systematic search of multiple major medical reference databases identified studies evaluating spinal fusion in patients with degenerative joint disease using ICBG, local autograft, or allograft in the thoracolumbar spine. Results  Six comparative studies met our inclusion criteria. A “low” strength of the overall body of evidence suggested no difference in fusion percentages in the lumbar spine between local autograft and ICBG. We found no difference in fusion percentages based on low evidence comparing allograft with ICBG autograft. There were no differences in pain or functional results comparing local autograft or allograft with ICBG autograft. Donor site pain and hematoma/seroma occurred more frequently in ICBG autograft group for lumbar fusion procedures. There was low evidence around the estimate of patients with donor site pain following ICBG harvesting, ranging from 16.7 to 20%. With respect to revision, low evidence demonstrated no difference between allograft and ICBG autograft. There was no evidence comparing patients receiving allograft with local autograft for fusion, pain, functional, and safety outcomes. Conclusion  In the lumbar spine, ICBG, local autograft, and allograft have similar effectiveness in terms of fusion rates, pain scores, and functional outcomes. However, ICBG is associated with an increased risk for donor site-related complications. Significant limitations exist in the available literature when comparing ICBG, local autograft, and allograft for lumbar fusion, and thus ICBG versus other fusion methods necessitates further investigation. PMID:27556001

  20. Mechanical behaviour of Bioactive Glass granules and morselized cancellous bone allograft in load bearing defects.

    PubMed

    Hulsen, D J W; Geurts, J; van Gestel, N A P; van Rietbergen, B; Arts, J J

    2016-05-03

    Bioactive Glass (BAG) granules are osteoconductive and possess unique antibacterial properties for a synthetic biomaterial. To assess the applicability of BAG granules in load-bearing defects, the aim was to compare mechanical behaviour of graft layers consisting of BAG granules and morselized cancellous bone allograft in different volume mixtures under clinically relevant conditions. The graft layers were mechanically tested, using two mechanical testing modalities with simulated physiological loading conditions: highly controllable confined compression tests (CCT) and more clinically realistic in situ compression tests (ISCT) in cadaveric porcine bone defects. Graft layer impaction strain, residual strain, aggregate modulus, and creep strain were determined in CCT. Graft layer porosity was determined using micro computed tomography. The ISCT was used to determine graft layer subsidence in bone environment. ANOVA showed significant differences (p<0.001) between different graft layer compositions. True strains absolutely decreased for increasing BAG content: impaction strain -0.92 (allograft) to -0.39 (BAG), residual strain -0.12 to -0.01, and creep strain -0.09 to 0.00 respectively. Aggregate modulus increased with increasing BAG content from 116 to 653MPa. Porosity ranged from 66% (pure allograft) to 15% (pure BAG). Subsidence was highest for allograft, and remarkably low for a 1:1 BAG-allograft volume mixture. Both BAG granules and allograft morsels as stand-alone materials exhibit suboptimal mechanical behaviour for load-bearing purpose. BAG granules are difficult to handle and less porous, whereas allograft subsides and creeps. A 1:1 volume mixture of BAG and allograft is therefore proposed as the best graft material in load-bearing defects.

  1. High-Throughput Proteomic Approaches to the Elucidation of Potential Biomarkers of Chronic Allograft Injury (CAI)

    PubMed Central

    Cassidy, Hilary; Slyne, Jennifer; Frain, Helena; Slattery, Craig; Ryan, Michael P.; McMorrow, Tara

    2013-01-01

    This review focuses on the role of OMICs technologies, concentrating in particular on proteomics, in biomarker discovery in chronic allograft injury (CAI). CAI is the second most prevalent cause of allograft dysfunction and loss in the first decade post-transplantation, after death with functioning graft (DWFG). The term CAI, sometimes referred to as chronic allograft nephropathy (CAN), describes the deterioration of renal allograft function and structure as a result of immunological processes (chronic antibody-mediated rejection), and other non-immunological factors such as calcineurin inhibitor (CNI) induced nephrotoxicity, hypertension and infection. Current methods for assessing allograft function are costly, insensitive and invasive; traditional kidney function measurements such as serum creatinine and glomerular filtration rate (GFR) display poor predictive abilities, while the current “gold-standard” involving histological diagnosis with a renal biopsy presents its own inherent risks to the overall health of the allograft. As early as two years post-transplantation, protocol biopsies have shown more than 50% of allograft recipients have mild CAN; ten years post-transplantation more than 50% of the allograft recipients have progressed to severe CAN which is associated with diminishing graft function. Thus, there is a growing medical requirement for minimally invasive biomarkers capable of identifying the early stages of the disease which would allow for timely intervention. Proteomics involves the study of the expression, localization, function and interaction of the proteome. Proteomic technologies may be powerful tools used to identify novel biomarkers which would predict CAI in susceptible individuals. In this paper we will review the use of proteomics in the elucidation of novel predictive biomarkers of CAI in clinical, animal and in vitro studies. PMID:28250402

  2. Expression of growth arrest-specific gene 6 and its receptors in dysfunctional human renal allografts.

    PubMed

    Yin, Jian L; Hambly, Brett D; Bao, Shi S; Painter, Dorothy; Bishop, G Alex; Eris, Josette M

    2003-09-01

    Growth arrest-specific gene 6 (Gas6) and its receptors Rse, Axl and Mer have recently been found to be involved in a rat model of chronic allograft nephropathy (CAN). Thus, in this study we investigated the function of Gas6 and its receptors in human renal allograft dysfunction. Expression of Gas6 and its receptors was detected by immunohistochemical staining. Gas6 and its receptors were widely expressed in glomeruli, tubules and vessels of renal allografts. Gas6 expression was detected in normal-functioning allografts and was increased in acute rejection ( P<0.05), acute tubular necrosis ( P<0.05) and CAN ( P<0.01). Gas6 receptors were not upregulated in any of the allograft groups, except for the Axl receptor, which increased only in acute tubular necrosis ( P<0.01). Gas6 expression was also found to correspond with the expression of alpha-smooth muscle actin, a general marker of CAN ( r(2)=0.21, P<0.01). These findings suggest that Gas6, acting as a growth factor, is increased in the process of kidney allograft dysfunction and in CAN.

  3. The impact of donor-specific anti-HLA antibodies on late kidney allograft failure.

    PubMed

    Loupy, Alexandre; Hill, Gary S; Jordan, Stanley C

    2012-04-17

    Despite improvements in outcomes of renal transplantation, kidney allograft loss remains substantial, and is associated with increased morbidity, mortality and costs. Identifying the pathologic pathways responsible for allograft loss, and the attendant development of therapeutic interventions, will be one of the guiding future objectives of transplant medicine. One of the most important advances of the past decade has been the demonstration of the destructive power of anti-HLA alloantibodies and their association with antibody-mediated rejection (ABMR). Compelling evidence exists to show that donor-specific anti-HLA antibodies (DSAs) are largely responsible for the chronic deterioration of allografts, a condition previously attributed to calcineurin inhibitor toxicity and chronic allograft nephropathy. The emergence of sensitive techniques to detect DSAs, together with advances in the assessment of graft pathology, have expanded the spectrum of what constitutes ABMR. Today, subtler forms of rejection--such as indolent ABMR, C4d-negative ABMR, and transplant arteriopathy--are seen in which DSAs exert a marked pathological effect. In addition, arteriosclerosis, previously thought to be a bystander lesion related to the vicissitudes of aging, is accelerated in ABMR. Advances in our understanding of the pathological significance of DSAs and ABMR show their primacy in the mediation of chronic allograft destruction. Therapies aimed at B cells, plasma cells and antibodies will be important therapeutic options to improve the length and quality of kidney allograft survival.

  4. Identification of microRNAs involved in acute rejection and spontaneous tolerance in murine hepatic allografts

    PubMed Central

    Morita, Miwa; Chen, Jiajie; Fujino, Masayuki; Kitazawa, Yusuke; Sugioka, Atsushi; Zhong, Liang; Li, Xiao-Kang

    2014-01-01

    Graft acceptance without the need for immunosuppressive drugs is the ultimate goal of transplantation therapy. In murine liver transplantation, allografts are accepted across major histocompatibility antigen complex barriers without the use of immunosuppressive drugs and constitute a suitable model for research on immunological rejection and tolerance. MicroRNA (miRNA) has been known to be involved in the immunological responses. In order to identify mRNAs in spontaneous liver allograft tolerance, miRNA expression in hepatic allografts was examined using this transplantation model. According to the graft pathological score and function, miR-146a, 15b, 223, 23a, 27a, 34a and 451 were upregulated compared with the expression observed in the syngeneic grafts. In contrast, miR-101a, 101b and 148a were downregulated. Our results demonstrated the alteration of miRNAs in the allografts and may indicate the role of miRNAs in the induction of tolerance after transplantation. Furthermore, our data suggest that monitoring the graft expression of novel miRNAs may allow clinicians to differentiate between rejection and tolerance. A better understanding of the tolerance inducing mechanism observed in murine hepatic allografts may provide a therapeutic strategy for attenuating allograft rejection. PMID:25323448

  5. Systemic overexpression of matricellular protein CCN1 exacerbates obliterative bronchiolitis in mouse tracheal allografts.

    PubMed

    Raissadati, Alireza; Nykänen, Antti I; Tuuminen, Raimo; Syrjälä, Simo O; Krebs, Rainer; Arnaudova, Ralica; Rouvinen, Eeva; Wang, Xiaomin; Poller, Wolfgang; Lemström, Karl B

    2015-12-01

    Obliterative bronchiolitis (OB) involves airway epithelial detachment, fibroproliferation, and inflammation, resulting in chronic rejection and transplant failure. Cysteine-rich 61 (CCN1) is an integrin receptor antagonist with a context-dependent role in inflammatory and fibroproliferative processes. We used a mouse tracheal OB model to investigate the role of CCN1 in the development of lung allograft OB. C57Bl/6 mice received a systemic injection of CCN1-expressing adenoviral vectors 2 days prior to subcutaneous implantation of tracheal allografts from major MHC-mismatched BALB/c mice. We treated another group of tracheal allograft recipients with cyclic arginine-glycine-aspartic acid peptide to dissect the role of αvβ3-integrin signaling in mediating CCN1 effects in tracheal allografts. Allografts were removed 4 weeks after transplantation and analyzed for luminal occlusion, inflammation, and vasculogenesis. CCN1 overexpression induced luminal occlusion (P < 0.05), fibroproliferation, and smooth muscle cell proliferation (P < 0.05). Selective activation of αvβ3-integrin receptor failed to mimic the actions of CCN1, and blocking failed to inhibit the effects of CCN1 in tracheal allografts. In conclusion, CCN1 exacerbates tracheal OB by enhancing fibroproliferation via an αvβ3-integrin-independent pathway. Further experiments are required to uncover its potentially harmful role in the development of OB after lung transplantation.

  6. AA amyloidosis in the renal allograft: a report of two cases and review of the literature

    PubMed Central

    Rojas, Rebecca; Josephson, Michelle A.; Chang, Anthony; Meehan, Shane M.

    2012-01-01

    AA amyloidosis is a disorder characterized by the abnormal formation, accumulation and systemic deposition of fibrillary material that frequently involves the kidney. Recurrent AA amyloidosis in the renal allograft has been documented in patients with tuberculosis, familial Mediterranean fever, ankylosing spondylitis, chronic pyelonephritis and rheumatoid arthritis. De novo AA amyloidosis is rarely described. We report two cases of AA amyloidosis in the renal allograft. Our first case is a 47-year-old male with a history of ankylosing spondylitis who developed end-stage renal disease reportedly from tubulointerstitial nephritis from non-steroidal anti-inflammatory agent use. A biopsy was never performed. One year after transplantation, AA amyloidosis was identified in the femoral head and 8 years post-transplantation, AA amyloidosis was identified in the renal allograft. He was treated with colchicine and adalimumab and has stable renal function at 1 year-follow-up. Our second case is a 57-year-old male with a long history of intravenous drug use and hepatitis C infection who developed end-stage kidney disease due to AA amyloidosis. Our second patient's course was complicated by renal adenovirus, pulmonary aspergillosis and hepatitis C with AA amyloidosis subsequently being identified in the allograft 2.5 years post-transplantation. Renal allograft function remains stable 4-years post-transplantation. These reports describe clinical and pathologic features of two cases of AA amyloidosis presenting with proteinuria and focal involvement of the renal allograft. PMID:22833808

  7. Endogenous Memory CD8 T Cells Directly Mediate Cardiac Allograft Rejection

    PubMed Central

    Su, C. A.; Iida, S.; Abe, T.; Fairchild, R. L.

    2014-01-01

    Differences in levels of environmentally induced memory T cells that cross-react with donor MHC molecules are postulated to account for the efficacy of allograft tolerance inducing strategies in rodents versus their failure in nonhuman primates and human transplant patients. Strategies to study the impact of donor-reactive memory T cells on allografts in rodents have relied on the pre-transplant induction of memory T cells cross-reactive with donor allogeneic MHC molecules through recipient viral infection, priming directly with donor antigen, or adoptive transfer of donor-antigen primed memory T cells. Each approach accelerates allograft rejection and confers resistance to tolerance induction, but also biases the T cell repertoire to strong donor-reactivity. The ability of endogenous memory T cells within unprimed mice to directly reject an allograft is unknown. Here we show a direct association between increased duration of cold ischemic allograft storage and numbers and enhanced functions of early graft infiltrating endogenous CD8 memory T cells. These T cells directly mediate rejection of allografts subjected to prolonged ischemia and this rejection is resistant to costimulatory blockade. These findings recapitulate the clinically significant impact of endogenous memory T cells with donor reactivity in a mouse transplant model in the absence of prior recipient priming. PMID:24502272

  8. The effects of prolonged deep freezing on the biomechanical properties of osteochondral allografts.

    PubMed

    Rozen, Benjamin; Brosh, Tamar; Salai, Moshe; Herman, Amir; Dudkiewicz, Israel

    2009-02-01

    Musculo-skeletal allografts sterilized and deep frozen are among the most common human tissue to be preserved and utilized in modern medicine. The effects of a long deep freezing period on cortical bone has already been evaluated and found to be insignificant. However, there are no reports about the influences of a protracted deep freezing period on osteochondral allografts. One hundred osteochondral cylinders were taken from a fresh specimen and humeral heads of 1 year, 2 years, 3 years and 4 year old bones. Twenty chips from each period, with a minimum of 3 chips per humeral head. Each was mechanically tested by 3 point compression. The fresh osteochondral allografts were significantly mechanically better than the deep frozen osteochondral allografts. There was no statistical significant time dependent difference between the deep frozen groups in relation to the freezing period. Therefore, we conclude that, from the mechanical point of view deep freezing of osteochondral allografts over a period of 4 years, is safe without further deterioration of the biomechanical properties of the osteochondral allografts.

  9. Clinical Outcomes of Cryopreserved Arterial Allograft Used as a Vascular Conduit for Hemodialysis

    PubMed Central

    Ha, Tae-Yong; Kim, Young Hoon; Chang, Jai Won; Park, Yangsoon; Han, Youngjin; Kwon, Hyunwook; Kwon, Tae-Won; Han, Duck Jong; Lee, Sung-Gyu

    2016-01-01

    This single center cohort study aimed to test the hypothesis that use of a cryopreserved arterial allograft could avoid the maturation or healing process of a new vascular access and to evaluate the patency of this technique compared with that of vascular access using a prosthetic graft. Between April 2012 and March 2013, 20 patients underwent an upper arm vascular access using a cryopreserved arterial allograft for failed or failing vascular accesses and 53 using a prosthetic graft were included in this study. The mean duration of catheter dependence, calculated as the time interval from upper arm access placement to removal of the tunneled central catheter after successful cannulation of the access, was significantly longer for accesses using a prosthetic graft than a cryopreserved arterial allograft (34.4 ± 11.39 days vs. 4.9 ± 8.5 days, P < 0.001). In the allograft group, use of vascular access started within 7 days in 16 patients (80%), as soon as from the day of surgery in 10 patients. Primary (unassisted; P = 0.314) and cumulative (assisted; P = 0.673) access survivals were similar in the two groups. There were no postoperative complications related to the use of a cryopreserved iliac arterial allograft except for one patient who experienced wound hematoma. In conclusion, upper arm vascular access using a cryopreserved arterial allograft may permit immediate hemodialysis without the maturation or healing process, resulting in access survival comparable to that of an access using a prosthetic graft. PMID:27478338

  10. Suppression of peripheral pain by blockade of Cav2.2 channels in nociceptors induces RANKL and impairs recovery from inflammatory arthritis

    PubMed Central

    Baddack, Uta; Frahm, Silke; Antolin-Fontes, Beatriz; Grobe, Jenny; Lipp, Martin; Müller, Gerd; Ibañez-Tallon, Ines

    2015-01-01

    Objective A hallmark of rheumatoid arthritis (RA) is the chronic pain that accompanies the inflammation and joint deformation. Patients with RA rate pain relief with highest priority, however, few studies have addressed the efficacy and safety of therapies directed specifically towards pain pathways. The conotoxin MVIIA (Prialt/Ziconotide) is used in humans to alleviate persistent pain syndromes because it specifically blocks the CaV2.2 voltage-gated calcium channel, which mediates the release of neurotransmitters and proinflammatory mediators from peripheral nociceptor nerve terminals. The purpose of this study was to investigate whether block of CaV2.2 can suppress arthritic pain, and to examine the progression of induced arthritis during persistent CaV2.2 blockade. Methods Transgenic mice (Tg-MVIIA) expressing a membrane-tethered form of the ω-conotoxin MVIIA, under the control of a nociceptor-specific gene, were employed. These mice were subjected to unilateral induction of joint inflammation using the Antigen- and Collagen-Induced Arthritis (ACIA) model. Results We observed that CaV2.2-blockade mediated by t-MVIIA effectively suppressed arthritis-induced pain; however, in contrast to their wild-type littermates, which ultimately regained use of their injured joint as inflammation subsides, Tg-MVIIA mice showed continued inflammation with an up-regulation of the osteoclast activator RANKL and concomitant joint and bone destruction. Conclusion Altogether, our results indicate that alleviation of peripheral pain by blockade of CaV2.2- mediated calcium influx and signaling in nociceptor sensory neurons, impairs recovery from induced arthritis and point to the potentially devastating effects of using CaV2.2 channel blockers as analgesics during inflammation. PMID:25733371

  11. Inhibitory gene expression of the Cav3.1 T-type calcium channel to improve neuronal injury induced by lidocaine hydrochloride.

    PubMed

    Wen, Xianjie; Xu, Shiyuan; Zhang, Qingguo; Li, Xiaohong; Liang, Hua; Yang, Chenxiang; Wang, Hanbing; Liu, Hongzhen

    2016-03-15

    Cav3.1 is a low-voltage-activated (LVA) calcium channel that plays a key role in regulating intracellular calcium ion levels. In this study, we observed the effects of lidocaine hydrochloride on the pshRNA-CACNA1G-SH-SY5Y cells that silenced Cav3.1 mRNA by RNA interference, and investigated the roles of p38 MAPK in these effects. We constructed the pNC-puro-CACNA1G-SH-SY5Y cells and pshRNA-CACNA1G -SH-SY5Y cells by the RNA interference. All the cells were cultured with or without 10mM lidocaine hydrochloride for 24 h. The cell morphology, cell viability, Cav3.1 and p38 protein expression, cell apoptosis rate and intracellular calcium ion concentration were detected. We found that all cells treated with 10mM lidocaine hydrochloride for 24 h showed cellular rounding, axonal regression, and cellular floating. Compared with the cells in SH-SY5Y+Lido group and NC+Lido group, those in the RNAi+Lido group showed similar changes, but of smaller magnitude. Additionally, following lidocaine hydrochloride all cells displayed increased Cav3.1 and p38 MAPK protein, apoptosis rate, and intracellular calcium ion levels; however,these changes in the RNAi+Lido group were less pronounced than in the SH-SY5Y+Lido and NC+Lido groups. The cell viability decreased following lidocaine hydrochloride treatment, but viability of the cells in the RNAi+Lido group was higher than in the SH-SY5Y+Lido and NC+Lido groups. The results showed that Cav3.1 may be involved in neuronal injury induced by lidocaine hydrochloride and that p38 MAPK phosphorylation was reduced upon Cav3.1 gene silencing.

  12. Rem, a member of the RGK GTPases, inhibits recombinant CaV1.2 channels using multiple mechanisms that require distinct conformations of the GTPase.

    PubMed

    Yang, Tingting; Xu, Xianghua; Kernan, Timothy; Wu, Vincent; Colecraft, Henry M

    2010-05-15

    Rad/Rem/Gem/Kir (RGK) GTPases potently inhibit Ca(V)1 and Ca(V)2 (Ca(V)1-2) channels, a paradigm of ion channel regulation by monomeric G-proteins with significant physiological ramifications and potential biotechnology applications. The mechanism(s) underlying how RGK proteins inhibit I(Ca) is unknown, and it is unclear how key structural and regulatory properties of these GTPases (such as the role of GTP binding to the nucleotide binding domain (NBD), and the C-terminus which contains a membrane-targeting motif) feature in this effect. Here, we show that Rem inhibits Ca(V)1.2 channels by three independent mechanisms that rely on distinct configurations of the GTPase: (1) a reduction in surface density of channels is accomplished by enhancing dynamin-dependent endocytosis, (2) a diminution of channel open probability (P(o)) that occurs without impacting on voltage sensor movement, and (3) an immobilization of Ca(V) channel voltage sensors. The presence of both the Rem NBD and C-terminus (whether membrane-targeted or not) in one molecule is sufficient to reconstitute all three mechanisms. However, membrane localization of the NBD by a generic membrane-targeting module reconstitutes only the decreased P(o) function (mechanism 2). A point mutation that prevents GTP binding to the NBD selectively eliminates the capacity to immobilize voltage sensors (mechanism 3). The results reveal an uncommon multiplicity in the mechanisms Rem uses to inhibit I(Ca), predict new physiological dimensions of the RGK GTPase-Ca(V) channel crosstalk, and suggest original approaches for developing novel Ca(V) channel blockers.

  13. Ultrastructural evidence for pre- and postsynaptic localization of Cav1.2 L-type Ca2+ channels in the rat hippocampus.

    PubMed

    Tippens, Alyssa L; Pare, Jean-Francois; Langwieser, Nicole; Moosmang, Sven; Milner, Teresa A; Smith, Yoland; Lee, Amy

    2008-02-01

    In the hippocampal formation, Ca(v)1.2 (L-type) voltage-gated Ca(2+) channels mediate Ca(2+) signals that can trigger long-term alterations in synaptic efficacy underlying learning and memory. Immunocytochemical studies indicate that Ca(v)1.2 channels are localized mainly in the soma and proximal dendrites of hippocampal pyramidal neurons, but electrophysiological data suggest a broader distribution of these channels. To define the subcellular substrates underlying Ca(v)1.2 Ca(2+) signals, we analyzed the localization of Ca(v)1.2 in the hippocampal formation by using antibodies against the pore-forming alpha(1)-subunit of Ca(v)1.2 (alpha(1)1.2). By light microscopy, alpha(1)1.2-like immunoreactivity (alpha(1)1.2-IR) was detected in pyramidal cell soma and dendritic fields of areas CA1-CA3 and in granule cell soma and fibers in the dentate gyrus. At the electron microscopic level, alpha(1)1.2-IR was localized in dendrites, but also in axons, axon terminals, and glial processes in all hippocampal subfields. Plasmalemmal immunogold particles representing alpha(1)1.2-IR were more significant for small- than large-caliber dendrites and were largely associated with extrasynaptic regions in dendritic spines and axon terminals. These findings provide the first detailed ultrastructural analysis of Ca(v)1.2 localization in the brain and support functionally diverse roles of these channels in the hippocampal formation.

  14. Lyophilized allografts without pre-treatment with glutaraldehyde are more suitable than cryopreserved allografts for pulmonary artery reconstruction

    PubMed Central

    Olmos-Zúãiga, J.R.; Jasso-Victoria, R.; Díaz-Martínez, N.E.; Gaxiola-Gaxiola, M.O.; Sotres-Vega, A.; Heras-Romero, Y.; Baltazares-Lipp, M.; Baltazares-Lipp, M.E.; Santillán-Doherty, P.; Hernández-Jiménez, C.

    2015-01-01

    Various methods are available for preservation of vascular grafts for pulmonary artery (PA) replacement. Lyophilization and cryopreservation reduce antigenicity and prevent thrombosis and calcification in vascular grafts, so both methods can be used to obtain vascular bioprostheses. We evaluated the hemodynamic, gasometric, imaging, and macroscopic and microscopic findings produced by PA reconstruction with lyophilized (LyoPA) grafts and cryopreserved (CryoPA) grafts in dogs. Eighteen healthy crossbred adult dogs of both sexes weighing between 18 and 20 kg were used and divided into three groups of six: group I, PA section and reanastomosis; group II, PA resection and reconstruction with LyoPA allograft; group III, PA resection and reconstruction with CryoPA allograft. Dogs were evaluated 4 weeks after surgery, and the status of the graft and vascular anastomosis were examined macroscopically and microscopically. No clinical, radiologic, or blood-gas abnormalities were observed during the study. The mean pulmonary artery pressure (MPAP) in group III increased significantly at the end of the study compared with baseline (P=0.02) and final [P=0.007, two-way repeat-measures analysis of variance (RM ANOVA)] values. Pulmonary vascular resistance of groups II and III increased immediately after reperfusion and also at the end of the study compared to baseline. The increase shown by group III vs group I was significant only if compared with after surgery and study end (P=0.016 and P=0.005, respectively, two-way RM ANOVA). Microscopically, permeability was reduced by ≤75% in group III. In conclusion, substitution of PAs with LyoPA grafts is technically feasible and clinically promising. PMID:26648092

  15. Lyophilized allografts without pre-treatment with glutaraldehyde are more suitable than cryopreserved allografts for pulmonary artery reconstruction.

    PubMed

    Olmos-Zúñiga, J R; Jasso-Victoria, R; Díaz-Martínez, N E; Gaxiola-Gaxiola, M O; Sotres-Vega, A; Heras-Romero, Y; Baltazares-Lipp, M; Baltazares-Lipp, M E; Santillán-Doherty, P; Hernández-Jiménez, C

    2016-02-01

    Various methods are available for preservation of vascular grafts for pulmonary artery (PA) replacement. Lyophilization and cryopreservation reduce antigenicity and prevent thrombosis and calcification in vascular grafts, so both methods can be used to obtain vascular bioprostheses. We evaluated the hemodynamic, gasometric, imaging, and macroscopic and microscopic findings produced by PA reconstruction with lyophilized (LyoPA) grafts and cryopreserved (CryoPA) grafts in dogs. Eighteen healthy crossbred adult dogs of both sexes weighing between 18 and 20 kg were used and divided into three groups of six: group I, PA section and reanastomosis; group II, PA resection and reconstruction with LyoPA allograft; group III, PA resection and reconstruction with CryoPA allograft. Dogs were evaluated 4 weeks after surgery, and the status of the graft and vascular anastomosis were examined macroscopically and microscopically. No clinical, radiologic, or blood-gas abnormalities were observed during the study. The mean pulmonary artery pressure (MPAP) in group III increased significantly at the end of the study compared with baseline (P=0.02) and final [P=0.007, two-way repeat-measures analysis of variance (RM ANOVA)] values. Pulmonary vascular resistance of groups II and III increased immediately after reperfusion and also at the end of the study compared to baseline. The increase shown by group III vs group I was significant only if compared with after surgery and study end (P=0.016 and P=0.005, respectively, two-way RM ANOVA). Microscopically, permeability was reduced by ≤75% in group III. In conclusion, substitution of PAs with LyoPA grafts is technically feasible and clinically promising.

  16. Structural bone allograft combined with genetically engineered mesenchymal stem cells as a novel platform for bone tissue engineering.

    PubMed

    Xie, Chao; Reynolds, David; Awad, Hani; Rubery, Paul T; Pelled, Gadi; Gazit, Dan; Guldberg, Robert E; Schwarz, Edward M; O'Keefe, Regis J; Zhang, Xinping

    2007-03-01

    The presence of live periosteal progenitor cells on the surface of bone autografts confers better healing than devitalized allograft. We have previously demonstrated in a murine 4 mm segmental femoral bone-grafting model that live periosteum produces robust endochondral and intramembraneous bone formation that is essential for effective healing and neovascularization of structural bone grafts. To the end of engineering a live pseudo-periosteum that could induce a similar response onto devitalized bone allograft, we seeded a mesenchymal stem cell line stably transfected with human bone morphogenic protein-2/beta-galactosidase (C9) onto devitalized bone allografts or onto a membranous small intestinal submucosa scaffold that was wrapped around the allograft. Histology showed that C9-coated allografts displayed early cartilaginous tissue formation at day 7. By 6 and 9 weeks, a new cortical shell was found bridging the segmental defect that united the host bones. Biomechanical testing showed that C9-coated allografts displayed torsional strength and stiffness equivalent to intact femurs at 6 weeks and superior to live isografts at 9 weeks. Volumetric and histomorphometric micro-computed tomography analyses demonstrated a 2-fold increase in new bone formation around C9-coated allografts, which resulted in a substantial increase in polar moment of inertia (pMOI) due to the formation of new cortical shell around the allografts. Positive correlations between biomechanics and new bone volume and pMOI were found, suggesting that the biomechanical function of the grafted femur relates to both morphological parameters. C9-coated allograft also exhibited slower resorption of the graft cortex at 9 weeks than live isograft. Both new bone formation and the persistent allograft likely contributed to the improved biomechanics of C9-coated allograft. Taken together, we propose a novel strategy to combine structural bone allograft with genetically engineered mesenchymal stem cells as

  17. Trafficking of donor-derived bone marrow correlates with chimerism and extension of composite allograft survival across MHC barrier.

    PubMed

    Ozmen, S; Ulusal, B G; Ulusal, A E; Izycki, D; Yoder, B; Siemionow, M

    2006-06-01

    We proposed to evaluate differences between recipient's immune response to vascularized skin and combined vascularized skin/bone allografts, under a 7-day alphabeta-TCR plus cyclosporine (CsA) treatment protocol. Thirty-six transplantations were performed in six groups: group I (isograft control-vascularized skin graft; n=6); group II (isograft control-combined vascularized skin/bone graft; n=6); group III (allograft rejection control group-vascularized skin graft; n=6); group IV (allograft rejection control-combined vascularized skin/bone graft; n=6); group V (allograft treatment-vascularized skin graft; n=6); and group VI (allograft treatment-combined vascularized skin/bone graft; n=6). Isograft transplantations were performed between Lewis rats and allografts were transplanted across the MHC barrier from Brown Norway to Lewis rats. In the allograft treatment group, a combined alphabeta-TCR+CsA protocol was applied for 7 days. All groups were compared clinically, immunologically and histologically. Statistical significance was determined with two-tailed Student's t test. Indefinite graft survival was achieved in the isograft control group (>300 days). Allograft rejection controls rejected within 5 to 9 days posttransplant; chimerism levels were undetectable (<.5%). Allografts under the alphabeta-TCR+CsA protocol had significantly extended survival when skin was combined with bone (61-125 days) compared to vascularized skin allografts (43-61 days). Lymphoid macrochimerism was significantly higher in group VI than group V. Histology confirmed skin and bone viability. Combined vascularized skin/bone allografts had higher and sustained levels of donor-specific chimerism and extended allograft survival.

  18. Multicenter Analysis of Immune Biomarkers and Heart Transplant Outcomes: Results of the Clinical Trials in Organ Transplantation-05 Study.

    PubMed

    Starling, R C; Stehlik, J; Baran, D A; Armstrong, B; Stone, J R; Ikle, D; Morrison, Y; Bridges, N D; Putheti, P; Strom, T B; Bhasin, M; Guleria, I; Chandraker, A; Sayegh, M; Daly, K P; Briscoe, D M; Heeger, P S

    2016-01-01

    Identification of biomarkers that assess posttransplant risk is needed to improve long-term outcomes following heart transplantation. The Clinical Trials in Organ Transplantation (CTOT)-05 protocol was an observational, multicenter, cohort study of 200 heart transplant recipients followed for the first posttransplant year. The primary endpoint was a composite of death, graft loss/retransplantation, biopsy-proven acute rejection (BPAR), and cardiac allograft vasculopathy (CAV) as defined by intravascular ultrasound (IVUS). We serially measured anti-HLA- and auto-antibodies, angiogenic proteins, peripheral blood allo-reactivity, and peripheral blood gene expression patterns. We correlated assay results and clinical characteristics with the composite endpoint and its components. The composite endpoint was associated with older donor allografts (p < 0.03) and with recipient anti-HLA antibody (p < 0.04). Recipient CMV-negativity (regardless of donor status) was associated with BPAR (p < 0.001), and increases in plasma vascular endothelial growth factor-C (OR 20; 95%CI:1.9-218) combined with decreases in endothelin-1 (OR 0.14; 95%CI:0.02-0.97) associated with CAV. The remaining biomarkers showed no relationships with the study endpoints. While suboptimal endpoint definitions and lower than anticipated event rates were identified as potential study limitations, the results of this multicenter study do not yet support routine use of the selected assays as noninvasive approaches to detect BPAR and/or CAV following heart transplantation.

  19. Cavβ2 transcription start site variants modulate calcium handling in newborn rat cardiomyocytes.

    PubMed

    Moreno, Cristian; Hermosilla, Tamara; Morales, Danna; Encina, Matías; Torres-Díaz, Leandro; Díaz, Pablo; Sarmiento, Daniela; Simon, Felipe; Varela, Diego

    2015-12-01

    In the heart, the main pathway for calcium influx is mediated by L-type calcium channels, a multi-subunit complex composed of the pore-forming subunit CaV1.2 and the auxiliary subunits CaVα2δ1 and CaVβ2. To date, five distinct CaVβ2 transcriptional start site (TSS) variants (CaVβ2a-e) varying only in the composition and length of the N-terminal domain have been described, each of them granting distinct biophysical properties to the L-type current. However, the physiological role of these variants in Ca(2+) handling in the native tissue has not been explored. Our results show that four of these variants are present in neonatal rat cardiomyocytes. The contribution of those CaVβ2 TSS variants on endogenous L-type current and Ca(2+) handling was explored by adenoviral-mediated overexpression of each CaVβ2 variant in cultured newborn rat cardiomyocytes. As expected, all CaVβ2 TSS variants increased L-type current density and produced distinctive changes on L-type calcium channel (LTCC) current activation and inactivation kinetics. The characteristics of the induced calcium transients were dependent on the TSS variant overexpressed. Moreover, the amplitude of the calcium transients varied depending on the subunit involved, being higher in cardiomyocytes transduced with CaVβ2a and smaller in CaVβ2d. Interestingly, the contribution of Ca(2+) influx and Ca(2+) release on total calcium transients, as well as the sarcoplasmic calcium content, was found to be TSS-variant-dependent. Remarkably, determination of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) messenger RNA (mRNA) abundance and cell size change indicates that CaVβ2 TSS variants modulate the cardiomyocyte hypertrophic state. In summary, we demonstrate that expression of individual CaVβ2 TSS variants regulates calcium handling in cardiomyocytes and, consequently, has significant repercussion in the development of hypertrophy.

  20. Use of polyvinylpyrrolidone-iodine solution for sterilisation and preservation improves mechanical properties and osteogenesis of allografts

    NASA Astrophysics Data System (ADS)

    Zhao, Yantao; Hu, Xiantong; Li, Zhonghai; Wang, Fuli; Xia, Yang; Hou, Shuxun; Zhong, Hongbin; Zhang, Feimin; Gu, Ning

    2016-12-01

    Allografts eliminate the disadvantages associated with autografts and synthetic scaffolds but are associated with a disease-transmission risk. Therefore, allograft sterilisation is crucial. We aimed to determine whether polyvinylpyrrolidone-iodine (PVP-I) can be used for sterilisation and as a new wet-preservation method. PVP-I–sterilised and preserved allografts demonstrated improved mechanical property, osteogenesis, and excellent microbial inhibition. A thigh muscle pouch model of nude mice showed that PVP-I–preserved allografts demonstrated better ectopic formation than Co60-sterilised allografts (control) in vivo (P < 0.05). Furthermore, the PVP-I–preserved group showed no difference between 24 h and 12 weeks of allograft preservation (P > 0.05). PVP-I–preserved allografts showed more hydrophilic surfaces and PVP-I–sterilised tendons showed higher mechanical strength than Co60-sterilised tendons (P < 0.05). The level of residual PVP-I was higher without washing and with prolonged preservation (P < 0.05). In vitro cellular tests showed that appropriate PVP-I concentration was nontoxic to preosteoblast cells, and cellular differentiation measured by alkaline phosphatase activity and osteogenic gene markers was enhanced (P < 0.05). Therefore, the improved biological performance of implanted allografts may be attributable to better surface properties and residual PVP-I, and PVP-I immersion can be a simple, easy method for allograft sterilisation and preservation.

  1. Studies on the antigenicity of bone. I. Freeze-dried and deep-frozen bone allografts in rabbits.

    PubMed

    Friedlaender, G E; Strong, D M; Sell, K W

    1976-09-01

    The antigenicity of deep-frozen and freeze-dried cortical and corticocancellous bone allografts placed orthotopically in rabbits was studied using a sensitive microcytotoxicity assay. Target cells were phytohemagglutinin-P-stimulated, 51chromium-labeled peripheral blood lymphocytes from the bone donors (Dutch belted rabbits), and sera or peripheral blood lymphocytes from the graft recipients (New Zealand white rabbits) were used as effectors of cytotoxicity. Fresh allografts and deep-frozen corticocancellous bone evoked detectable humoral and cell-mediated immunity,, whereas freeze-dried cortical bone allografts failed to sensitize the recipients and were the least antigenic of the allografts examined.

  2. [Neurologic complications induced by the treatment of the acute renal allograft rejection with the monoclonal antibody OKT3].

    PubMed

    Fernández, O; Romero, F; Bravo, M; Burgos, D; Cabello, M; González-Molina, M

    1993-10-01

    The treatment of the acute renal allograft rejection with the monoclonal antibody orthoclone OKT3 produces both systemic and neurologic alterations. In a series of 21 patients with an acute renal allograft rejection treated with this monoclonal antibody, 20 with a renal allograft transplantation and one with a renal and pancreatic allograft transplantation, 29% referred headache associated with fever and vomiting, and 14.2% presented severe neurological alterations induced by the treatment. We stress the need to know these secondary effects to differentiate them from other central nervous system disorders, particularly those of infectious origin.

  3. Use of polyvinylpyrrolidone-iodine solution for sterilisation and preservation improves mechanical properties and osteogenesis of allografts

    PubMed Central

    Zhao, Yantao; Hu, Xiantong; Li, Zhonghai; Wang, Fuli; Xia, Yang; Hou, Shuxun; Zhong, Hongbin; Zhang, Feimin; Gu, Ning

    2016-01-01

    Allografts eliminate the disadvantages associated with autografts and synthetic scaffolds but are associated with a disease-transmission risk. Therefore, allograft sterilisation is crucial. We aimed to determine whether polyvinylpyrrolidone-iodine (PVP-I) can be used for sterilisation and as a new wet-preservation method. PVP-I–sterilised and preserved allografts demonstrated improved mechanical property, osteogenesis, and excellent microbial inhibition. A thigh muscle pouch model of nude mice showed that PVP-I–preserved allografts demonstrated better ectopic formation than Co60-sterilised allografts (control) in vivo (P < 0.05). Furthermore, the PVP-I–preserved group showed no difference between 24 h and 12 weeks of allograft preservation (P > 0.05). PVP-I–preserved allografts showed more hydrophilic surfaces and PVP-I–sterilised tendons showed higher mechanical strength than Co60-sterilised tendons (P < 0.05). The level of residual PVP-I was higher without washing and with prolonged preservation (P < 0.05). In vitro cellular tests showed that appropriate PVP-I concentration was nontoxic to preosteoblast cells, and cellular differentiation measured by alkaline phosphatase activity and osteogenic gene markers was enhanced (P < 0.05). Therefore, the improved biological performance of implanted allografts may be attributable to better surface properties and residual PVP-I, and PVP-I immersion can be a simple, easy method for allograft sterilisation and preservation. PMID:27934929

  4. Spheroid formation of human thyroid cancer cells under simulated microgravity: a possible role of CTGF and CAV1

    PubMed Central

    2014-01-01

    Background Multicellular tumor spheroids (MCTS) formed scaffold-free under microgravity are of high interest for research and medicine. Their formation mechanism can be studied in space in real microgravity or on Earth using ground-based facilities (GBF), which simulate microgravity. On Earth, these experiments are more cost-efficient and easily performable. However, each GBF might exert device-specific and altered superimposingly gravity-dependent effects on the cells. Results FTC-133 human thyroid cancer cells were cultivated on a 2D clinostat (CN) and a random positioning machine (RPM) and compared with corresponding 1 g control cells. Harvested cell samples were investigated by microscopy, quantitative realtime-PCR and Multi-Analyte Profiling. Spheroid formation and growth occurred during 72 h of cultivation on both devices. Cytokine secretion and gene activation patterns frequently altered in different ways, when the cells were cultured either on the RPM or the CN. A decreased expression of CAV1 and CTGF in MCTS compared to adherent cells was observed after cultivation on both machines. Conclusion The development of MCTS proceeds similarly on the RPM and the CN resembling the situation observed under real microgravity conditions, while no MCTS formation was observed at 1 g under identical experimental conditions. Simultaneously, changes in the regulation of CTGF and CAV1 appeared in a comparable manner on both machines. A relationship between these molecules and MCTS formation is discussed. PMID:24885050

  5. CAV_KO: a Simple 1-D Langrangian Hydrocode for MS EXCEL™ with Automatic Generation of X-T Diagrams

    NASA Astrophysics Data System (ADS)

    Tsembelis, K.; Ramsden, B.; Proud, W. G.; Borg, J.

    2007-12-01

    Hydrocodes are widely used to predict or simulate highly dynamic and transient events such as blast and impact. Codes such as GRIM, CTH or AUTODYN are well developed and involve complex numerical methods and in many cases require a large computing infrastructure. In this paper we present a simple 1-D Langrangian hydrocode developed at the University of Cambridge, called CAV_KO written in Visual Basic. The motivation being to produce a code which, while being relatively simple, is useful for both experimental planning and teaching. The code has been adapted from the original KO code written in FORTRAN by J. Borg, which, in turn, is based on the algorithm developed by Wilkins [1]. The developed GUI within MS Excel™ and the automatic generation of x-t diagrams allow CAV_KO to be a useful tool for quick calculations of plate impact events and teaching purposes. The VB code is licensed under the GNU General Public License and a MS Excel™ spreadsheet containing the code can be downloaded from www.shockphysics.com together with a copy of the user guide.

  6. A rare schizophrenia risk variant of CACNA1I disrupts CaV3.3 channel activity

    PubMed Central

    Andrade, A.; Hope, J.; Allen, A.; Yorgan, V.; Lipscombe, D.; Pan, J. Q.

    2016-01-01

    CACNA1I is a candidate schizophrenia risk gene. It encodes the pore-forming human CaV3.3 α1 subunit, a subtype of voltage-gated calcium channel that contributes to T-type currents. Recently, two de novo missense variations, T797M and R1346H, of hCaV3.3 were identified in individuals with schizophrenia. Here we show that R1346H, but not T797M, is associated with lower hCaV3.3 protein levels, reduced glycosylation, and lower membrane surface levels of hCaV3.3 when expressed in human cell lines compared to wild-type. Consistent with our biochemical analyses, whole-cell hCaV3.3 currents in cells expressing the R1346H variant were ~50% of those in cells expressing WT hCaV3.3, and neither R1346H nor T797M altered channel biophysical properties. Employing the NEURON simulation environment, we found that reducing hCaV3.3 current densities by 22% or more eliminates rebound bursting in model thalamic reticular nucleus (TRN) neurons. Our analyses suggest that a single copy of Chr22: 39665939G > A CACNA1I has the capacity to disrupt CaV3.3 channel-dependent functions, including rebound bursting in TRN neurons, with potential implications for schizophrenia pathophysiology. PMID:27756899

  7. New 5-unsubstituted dihydropyridines with improved CaV1.3 selectivity as potential neuroprotective agents against ischemic injury.

    PubMed

    Tenti, Giammarco; Parada, Esther; León, Rafael; Egea, Javier; Martínez-Revelles, Sonia; Briones, Ana María; Sridharan, Vellaisamy; López, Manuela G; Ramos, María Teresa; Menéndez, J Carlos

    2014-05-22

    C5-unsubstituted-C6-aryl-1,4-dihydropyridines were prepared by a CAN-catalyzed multicomponent reaction from chalcones, β-dicarbonyl compounds, and ammonium acetate. These compounds were able to block Ca(2+) entry after a depolarizing stimulus and showed an improved Cav1.3/Cav1.2 selectivity in comparison with nifedipine. Furthermore, they were able to protect neuroblastoma cells against Ca(2+) overload and oxidative stress models. Their selectivity ratio makes them highly interesting for the treatment of neurological disorders where Ca(2+) dyshomeostasis and high levels of oxidative stress have been demonstrated. Furthermore, their low potency toward the cardiovascular channel subtype makes them safer by reducing their probable side effects, in comparison to classical 1,4-dihydropyridines. Some compounds afforded good protective profile in a postincubation model that simulates the real clinical situation of ictus patients, offering a therapeutic window of opportunity of great interest for patient recovery after a brain ischemic episode. Good activities were also found in acute ischemia/reperfusion models of oxygen and glucose deprivation.

  8. A Novel Cardioprotective Agent in Cardiac Transplantation: Metformin Activation of AMP-Activated Protein Kinase Decreases Acute Ischemia-Reperfusion Injury and Chronic Rejection

    PubMed Central

    Chin, Jocelyn T.; Troke, Joshua J.; Kimura, Naoyuki; Itoh, Satoshi; Wang, Xi; Palmer, Owen P.; Robbins, Robert C.; Fischbein, Michael P.

    2011-01-01

    The main cause of mortality after the first year from cardiac transplantation is cardiac allograft vasculopathy (CAV), which leads to chronic rejection of the heart. To improve long-term outcomes in cardiac transplantation, treatments to prevent or diminish CAV are actively being researched. Ischemia-reperfusion (I-R) injury has been shown to be the strongest alloantigen-independent factor in the development of CAV. Here, we investigate the use of metformin in murine cardiac transplantation models as a novel cardioprotective agent to limit acute I-R injury and subsequent chronic rejection. We show that metformin treatment activates AMP-activated kinase (AMPK) in vitro and in vivo. In the acute transplantation model, metformin activation of AMPK resulted in significantly decreased apoptosis in cardiac allografts on postoperative day (POD) 1 and 8. In the chronic transplantation model, metformin pretreatment of allografts led to significantly improved graft function and significantly decreased CAV, as measured on POD 52. Taken together, our results in the acute and chronic rejection studies suggest a potential cardioprotective mechanism for metformin; we demonstrate a correlation between metformin-induced decrease in acute I-R injury and metformin-related decrease in chronic rejection. Thus, one of the ways by which metformin and AMPK activation may protect the transplanted heart from chronic rejection is by decreasing initial I-R injury inherent in donor organ preservation and implantation. Our findings suggest novel therapeutic strategies for minimizing chronic cardiac rejection via the use of metformin- and AMPK-mediated pathways to suppress acute I-R injury. PMID:22180679

  9. A novel cardioprotective agent in cardiac transplantation: metformin activation of AMP-activated protein kinase decreases acute ischemia-reperfusion injury and chronic rejection.

    PubMed

    Chin, Jocelyn T; Troke, Joshua J; Kimura, Naoyuki; Itoh, Satoshi; Wang, Xi; Palmer, Owen P; Robbins, Robert C; Fischbein, Michael P

    2011-12-01

    The main cause of mortality after the first year from cardiac transplantation is cardiac allograft vasculopathy (CAV), which leads to chronic rejection of the heart. To improve long-term outcomes in cardiac transplantation, treatments to prevent or diminish CAV are actively being researched. Ischemia-reperfusion (I-R) injury has been shown to be the strongest alloantigen-independent factor in the development of CAV. Here, we investigate the use of metformin in murine cardiac transplantation models as a novel cardioprotective agent to limit acute I-R injury and subsequent chronic rejection. We show that metformin treatment activates AMP-activated kinase (AMPK) in vitro and in vivo. In the acute transplantation model, metformin activation of AMPK resulted in significantly decreased apoptosis in cardiac allografts on postoperative day (POD) 1 and 8. In the chronic transplantation model, metformin pretreatment of allografts led to significantly improved graft function and significantly decreased CAV, as measured on POD 52. Taken together, our results in the acute and chronic rejection studies suggest a potential cardioprotective mechanism for metformin; we demonstrate a correlation between metformin-induced decrease in acute I-R injury and metformin-related decrease in chronic rejection. Thus, one of the ways by which metformin and AMPK activation may protect the transplanted heart from chronic rejection is by decreasing initial I-R injury inherent in donor organ preservation and implantation. Our findings suggest novel therapeutic strategies for minimizing chronic cardiac rejection via the use of metformin- and AMPK-mediated pathways to suppress acute I-R injury.

  10. Osteoinductive effect of bone bank allografts on human osteoblasts in culture.

    PubMed

    de la Piedra, Concepción; Vicario, Carlos; de Acuña, Lucrecia Rodríguez; García-Moreno, Carmen; Traba, Maria Luisa; Arlandis, Santiago; Marco, Fernando; López-Durán, Luis

    2008-02-01

    Incorporation of a human bone allograft requires osteoclast activity and growth of recipient osteoblasts. The aim of this work was to study the effects produced by autoclavated and -80 degrees C frozen bone allografts on osteoblast proliferation and synthesis of interleukin 6 (IL6), activator of bone resorption, aminoterminal propeptide of procollagen I (PINP), marker of bone matrix formation, and osteoprotegerin (OPG), inhibitor of osteoclast activity and differentiation. Allografts were obtained from human femoral heads. Human osteoblasts were cultured in the presence (problem group) or in the absence (control group) of allografts during 15 days. Allografts produced a decrease in osteoblast proliferation in the first week of the experiment, and an increase in IL6 mRNA, both at 3 h and 2 days, and an increase in the IL6 released to the culture medium the second day of the experiment. We found a decrease in OPG released to the culture on the 2nd and fourth days. These results suggest an increase in bone resorption and a decrease in bone formation in the first week of the experiment. In the second week, allografts produced an increase in osteoblast proliferation and PINP release to the culture medium, indicating an increase in bone formation; an increase in OPG released to the culture medium, which would indicate a decrease in bone resorption; and a decrease in IL6, indicating a decrease in bone resorption stimulation. These results demonstrate that autoclavated and -80 degrees C frozen bone allografts produce in bone environment changes that regulate their own incorporation to the recipient bone.

  11. Mechanoreceptor Reinnervation of Autografts Versus Allografts After Anterior Cruciate Ligament Reconstruction

    PubMed Central

    Young, Simon W.; Valladares, Roberto D.; Loi, Florence; Dragoo, Jason L.

    2016-01-01

    Background: Loss of proprioceptive function occurs after anterior cruciate ligament (ACL) rupture. Clinical, motor, and proprioceptive function is known to improve after ACL reconstruction but does not return to normal. While histological studies of human ACL allografts have been unable to demonstrate mechanoreceptor reinnervation, animal data suggest that reinnervation may occur when an autograft is used. Purpose: To compare the presence or absence of mechanoreceptors between allograft versus autograft after ACL reconstruction in humans. Study Design: Cohort study; Level of evidence, 3. Methods: Ten patients with previous ACL reconstruction presenting for either revision ACL surgery or knee arthroscopy for other reasons were enrolled in a prospective, comparative study. Five patients had a previous autograft ACL and 5 patients had an allograft. Biopsies, either from intact or ruptured grafts, were taken from identical locations as close to the femoral and tibial insertions as possible. Specimens were stained with hematoxylin-eosin (H-E) and monoclonal antibodies against neurofilament protein (NFP), known to be present in mechanoreceptor tissue. Immunohistochemical examination was carried out, and the number of NFP+ neural tissue analogs was counted and compared with that of native ACL tissue. Results: The mean time between original graft and biopsy was 6.9 years (range, 0.5-15 years). Histological examination showed significantly less NFP+ neural analogs in allograft and autograft patients than control tissue (mean number of NFP+ analogs per high-power field, 0.7 ± 0.9 [allograft] and 0.5 ± 0.8 [autograft] vs 4.7 ± 0.9 [controls]; P < .0001). There was no significant difference in NFP analogs between autograft and allograft tissue. Conclusion: We found a reduced concentration of NFP+ neural analogs in ACL grafts compared with native ACL tissue. This deficit exists irrespective of whether allograft or autograft is used. These findings may explain the continued

  12. An audit of consent for allograft use in elective orthopaedic surgery.

    PubMed

    Mullan, C J; Pagoti, R; Davison, H; McAlinden, M G

    2016-04-01

    Introduction Patients receiving musculoskeletal allografts may be at risk of postoperative infection. The General Medical Council guidelines on consent highlight the importance of providing patients with the information they want or need on any proposed investigation or treatment, including any potential adverse outcomes. With the increased cost of defending medicolegal claims, it is paramount that adequate, clear informed patient consent be documented. Methods We retrospectively examined the patterns of informed consent for allograft bone use during elective orthopaedic procedures in a large unit with an onsite bone bank. The initial audit included patients operated over the course of 1 year. Following a feedback session, a re-audit was performed to identify improvements in practice. Results The case mix of both studies was very similar. Revision hip arthroplasty surgery constituted the major subgroup requiring allograft (48%), followed by foot and ankle surgery (16.3%) and revision knee arthroplasty surgery (11.4%) .On the initial audit, 17/45 cases (38%) had either adequate preoperative documentation of the outpatient discussion or an appropriately completed consent form on the planned use of allograft. On the re-audit, 44/78 cases (56%) had adequate pre-operative documentation. There was little correlation between how frequently a surgeon used allograft and the adequacy of consent (Correlation coefficient -0.12). Conclusions Although the risk of disease transmission with allograft may be variable, informed consent for allograft should be a routine part of preoperative discussions in elective orthopaedic surgery. Regular audit and feedback sessions may further improve consent documentation, alongside the targeting of high volume/low compliance surgeons.

  13. Infrequency of cytomegalovirus genome in coronary arteriopathy of human heart allografts.

    PubMed Central

    Gulizia, J. M.; Kandolf, R.; Kendall, T. J.; Thieszen, S. L.; Wilson, J. E.; Radio, S. J.; Costanzo, M. R.; Winters, G. L.; Miller, L. L.; McManus, B. M.

    1995-01-01

    In heart transplantation, long-term engraftment success is severely limited by the rapid development of obliterative disease of the coronary arteries. Data from various groups have been suggestive of a pathogenetic role of herpesviruses, particularly human cytomegalovirus, in accelerated allograft coronary artery disease; however, results are not yet conclusive. This study examines the hypothesis that human cytomegalovirus infection of allograft tissues is related pathogenetically and directly to accelerated coronary artery disease. Using in situ DNA hybridization and polymerase chain reaction, we examined particular coronary artery segments from 41 human heart allografts (ranging from 4 days to greater than 4 years after transplantation; mean, 457 days) and 22 donor age- and gender-comparable, coronary site-matched trauma victims for presence of human cytomegalovirus DNA. Human cytomegalovirus genome was detected in 8 of 41 (19.5%) allografts and in 1 of 22 (4.5%) control hearts. This difference in positivity was not statistically significant (P = 0.10). In the human cytomegalovirus-positive hearts, viral genome was localized to perivascular myocardium or coronary artery media or adventitia. Human cytomegalovirus genome was not detected in arterial intima of any allograft or control heart, although human cytomegalovirus genome was readily identified within intima of small pulmonary arteries from lung tissue with human cytomegalovirus pneumonitis. By statistical analyses, the presence of human cytomegalovirus genome was not associated with the nature or digitized extent of transplant arteriopathy, evidence of rejection, allograft recipient or donor serological data suggestive of human cytomegalovirus infection, duration of allograft implantation, or causes of death or retransplantation. Thus, our data indicate a low frequency of detectable human cytomegalovirus genome in accelerated coronary artery disease and do not support a direct role for human cytomegalovirus

  14. The protective effect of meniscus allograft transplantation on articular cartilage: a systematic review of animal studies.

    PubMed

    Rongen, J J; Hannink, G; van Tienen, T G; van Luijk, J; Hooijmans, C R

    2015-08-01

    Despite widespread reporting on clinical results, the effect of meniscus allograft transplantation on the development of osteoarthritis is still unclear. The aim of this study was to systematically review all studies on the effect of meniscus allograft transplantation on articular cartilage in animals. Pubmed and Embase were searched for original articles concerning the effect of meniscus allograft transplantation on articular cartilage compared with both its positive (meniscectomy) and negative (either sham or non-operated) control in healthy animals. Outcome measures related to assessment of damage to articular cartilage were divided in five principal outcome categories. Standardized mean differences (SMD) were calculated and pooled to obtain an overall SMD and 95% confidence interval. 17 articles were identified, representing 14 original animal cohorts with an average timing of data collection of 24 weeks [range 4 weeks; 30 months]. Compared to a negative control, meniscus allograft transplantation caused gross macroscopic (1.45 [0.95; 1.95]), histological (3.43 [2.25; 4.61]) damage to articular cartilage, and osteoarthritic changes on radiographs (3.12 [1.42; 4.82]). Moreover, results on histomorphometrics and cartilage biomechanics are supportive of this detrimental effect on cartilage. On the other hand, meniscus allograft transplantation caused significantly less gross macroscopic (-1.19 [-1.84; -0.54]) and histological (-1.70 [-2.67; -0.74]) damage to articular cartilage when compared to meniscectomy. However, there was no difference in osteoarthritic changes on plain radiographs (0.04 [-0.48; 0.57]), and results on histomorphometrics and biomechanics did neither show a difference in effect between meniscus allograft transplantation and meniscectomy. In conclusion, although meniscus allograft transplantation does not protect articular cartilage from damage, it reduces the extent of it when compared with meniscectomy.

  15. Donor-Specific Regulatory T Cells Acquired from Tolerant Mice Bearing Cardiac Allograft Promote Mixed Chimerism and Prolong Intestinal Allograft Survival

    PubMed Central

    Shen, Xiao-Fei; Jiang, Jin-Peng; Yang, Jian-Jun; Wang, Wei-Zhong; Guan, Wen-Xian; Du, Jun-Feng

    2016-01-01

    The induction of donor-specific transplant tolerance has always been a central problem for small bowel transplantation (SBT), which is thought to be the best therapy for end-stage bowel failure. With the development of new tolerance-inducing strategies, mixed chimerism induced by co-stimulation blockade has become most potent for tolerance of allografts, such as skin, kidney, and heart. However, a lack of clinically available co-stimulation blockers has hindered efficient application in humans. Furthermore, unlike those for other types of solid organ transplantation, strategies to induce robust mixed chimerism for intestinal allografts have not been fully developed. To improve current mixed chimerism induction protocols for future clinical application, we developed a new protocol using donor-specific regulatory T (Treg) cells from mice with heart allograft tolerance, immunosuppressive drugs which could be used clinically and low doses of irradiation. Our results demonstrated that donor-specific Treg cells acquired from tolerant mice after in vitro expansion generate stable chimerism and lead to acceptance of intestinal allograft. Increased intragraft Treg cells and clonal deletion contribute to the development of SBT tolerance. PMID:27909438

  16. Combined anti-ages and antioxidant activities of different solvent extracts of Solanum elaeagnifolium Cav (Solanacea) fruits during ripening and related to their phytochemical compositions

    PubMed Central

    Houda, Mejri; Derbré, Séverine; Jedy, Ahmed; Tlili, Nizar; Legault, Jean; Richomme, Pascal; Limam, Ferid; Saidani-Tounsi, Moufida

    2014-01-01

    Oxidative stress and advanced glycation end products (AGEs) are known as key factors for the development of diabetic complications such as retinopathy, cataract as well as atherosclerosis and neurodegenerative diseases, including Alzheimer’s diseases. In this context, natural products have been previously identified as promising sources for antioxidant and anti-glycation compounds. The current study focuses on the evaluation of antioxidant and glycation inhibitory activities of different solvent extracts of Solanum elaeagnifolium Cav (Solanaceae) fruits at different ripening stages. The results showed that antioxidant and anti-AGEs activities were significantly influenced by solvents polarities and ripening stages of S. elaeagnifolium Cav. With one exception, methanolic extract of overripe S. elaeagnifolium Cav fruit showed important protective effects against cellular oxidative stress. The aqueous extract showed the highest ABTS+ scavenging ability. Principal component analysis showed that total phenolic and flavonoid contents correlated well with observed antioxidants and anti-glycation activities. These results bring attention to the possible use of S. elaeagnifolium Cav as a valuable source of bioactive compounds exhibiting antioxidant effects and potentially alleviating diabetic complications. PMID:26417319

  17. An autism-associated mutation in CaV1.3 channels has opposing effects on voltage- and Ca(2+)-dependent regulation.

    PubMed

    Limpitikul, Worawan B; Dick, Ivy E; Ben-Johny, Manu; Yue, David T

    2016-06-03

    CaV1.3 channels are a major class of L-type Ca(2+) channels which contribute to the rhythmicity of the heart and brain. In the brain, these channels are vital for excitation-transcription coupling, synaptic plasticity, and neuronal firing. Moreover, disruption of CaV1.3 function has been associated with several neurological disorders. Here, we focus on the de novo missense mutation A760G which has been linked to autism spectrum disorder (ASD). To explore the role of this mutation in ASD pathogenesis, we examined the effects of A760G on CaV1.3 channel gating and regulation. Introduction of the mutation severely diminished the Ca(2+)-dependent inactivation (CDI) of CaV1.3 channels, an important feedback system required for Ca(2+) homeostasis. This reduction in CDI was observed in two major channel splice variants, though to different extents. Using an allosteric model of channel gating, we found that the underlying mechanism of CDI reduction is likely due to enhanced channel opening within the Ca(2+)-inactivated mode. Remarkably, the A760G mutation also caused an opposite increase in voltage-dependent inactivation (VDI), resulting in a multifaceted mechanism underlying ASD. When combined, these regulatory deficits appear to increase the intracellular Ca(2+) concentration, thus potentially disrupting neuronal development and synapse formation, ultimately leading to ASD.

  18. Cav3-type α1T calcium channels mediate transient calcium currents that regulate repetitive firing in Drosophila antennal lobe PNs.

    PubMed

    Iniguez, Jorge; Schutte, Soleil S; O'Dowd, Diane K

    2013-10-01

    Projection neurons (PNs), located in the antennal lobe region of the insect brain, play a key role in processing olfactory information. To explore how activity is regulated at the level of single PNs within this central circuit we have recorded from these neurons in adult Drosophila melanogaster brains. Our previous study demonstrated that PNs express voltage-gated calcium currents with a transient and sustained component. We found that the sustained component is mediated by cac gene-encoded Cav2-type channels involved in regulating action potential-independent release of neurotransmitter at excitatory cholinergic synapses. The function of the transient calcium current and the gene encoding the underlying channels, however, were unknown. Here we report that the transient current blocked by prepulse inactivation is sensitive to amiloride, a vertebrate Cav3-type channel blocker. In addition PN-specific RNAi knockdown of α1T, the Drosophila Cav3-type gene, caused a dramatic reduction in the transient current without altering the sustained component. These data demonstrate that the α1T gene encodes voltage-gated calcium channels underlying the amiloride-sensitive transient current. Alterations in evoked firing and spontaneous burst firing in the α1T knockdowns demonstrate that the Cav3-type calcium channels are important in regulating excitability in adult PNs.

  19. Voltage-independent inhibition of Ca(V)2.2 channels is delimited to a specific region of the membrane potential in rat SCG neurons.

    PubMed

    Vivas, Oscar; Arenas, Isabel; García, David E

    2012-06-01

    Neurotransmitters and hormones regulate Ca(V)2.2 channels through a voltage-independent pathway which is not well understood. It has been suggested that this voltage-independent inhibition is constant at all membrane voltages. However, changes in the percent of voltage-independent inhibition of Ca(V)2.2 have not been tested within a physiological voltage range. Here, we used a double-pulse protocol to isolate the voltage-independent inhibition of Ca(V)2.2 channels induced by noradrenaline in rat superior cervical ganglion neurons. To assess changes in the percent of the voltage-independent inhibition, the activation voltage of the channels was tested between -40 and +40 mV. We found that the percent of voltage-independent inhibition induced by noradrenaline changed with the activation voltage used. In addition, voltage-independent inhibition induced by oxo-M, a muscarinic agonist, exhibited the same dependence on activation voltage, which supports that this pattern is not exclusive for adrenergic activation. Our results suggested that voltage-independent inhibition of Ca(V)2.2 channels depends on the activation voltage of the channel in a physiological voltage range. This may have relevant implications in the understanding of the mechanism involved in voltage-independent inhibition.

  20. Resveratrol Ameliorates High Glucose and High-Fat/Sucrose Diet-Induced Vascular Hyperpermeability Involving Cav-1/eNOS Regulation

    PubMed Central

    Peng, Xiao lin; Qu, Wei; Wang, Lin zhi; Huang, Bin qing; Ying, Chen jiang; Sun, Xiu fa; Hao, Li ping

    2014-01-01

    Vascular endothelial hyperpermeability is one of the manifestations of endothelial dysfunction. Resveratrol (Res) is considered to be beneficial in protecting endothelial function. However, currently, the exact protective effect and involved mechanisms of Res on endothelial dysfunction-hyperpermeability have not been completely clarified. The aim of present study is to investigate the effects of Res on amelioration of endothelial hyperpermeability and the role of caveolin-1 (Cav-1)/endothelial nitric oxide synthase (eNOS) pathway. Adult male Wistar rats were treated with a normal or high-fat/sucrose diet (HFS) with or without Res for 13 weeks. HFS and in vitro treatment with high glucose increased hyperpermeability in rat aorta, heart, liver and kidney and cultured bovine aortic endothelial cells (BAECs), respectively, which was attenuated by Res treatment. Application of Res reversed the changes in eNOS and Cav-1 expressions in aorta and heart of rats fed HFS and in BAECs incubated with high glucose. Res stimulated the formation of NO inhibited by high glucose in BAECs. Beta-Cyclodextrin (β-CD), caveolae inhibitor, showed the better beneficial effect than Res alone to up-regulate eNOS phosphorylative levels, while NG-Nitro-77 L-arginine methyl ester (L-NAME), eNOS inhibitor, had no effect on Cav-1 expression. Our studies suggested that HFS and in vitro treatment with high glucose caused endothelial hyperpermeability, which were ameliorated by Res at least involving Cav-1/eNOS regulation. PMID:25419974

  1. Resveratrol ameliorates high glucose and high-fat/sucrose diet-induced vascular hyperpermeability involving Cav-1/eNOS regulation.

    PubMed

    Peng, Xiao Lin; Qu, Wei; Wang, Lin Zhi; Huang, Bin Qing; Ying, Chen Jiang; Sun, Xiu Fa; Hao, Li Ping

    2014-01-01

    Vascular endothelial hyperpermeability is one of the manifestations of endothelial dysfunction. Resveratrol (Res) is considered to be beneficial in protecting endothelial function. However, currently, the exact protective effect and involved mechanisms of Res on endothelial dysfunction-hyperpermeability have not been completely clarified. The aim of present study is to investigate the effects of Res on amelioration of endothelial hyperpermeability and the role of caveolin-1 (Cav-1)/endothelial nitric oxide synthase (eNOS) pathway. Adult male Wistar rats were treated with a normal or high-fat/sucrose diet (HFS) with or without Res for 13 weeks. HFS and in vitro treatment with high glucose increased hyperpermeability in rat aorta, heart, liver and kidney and cultured bovine aortic endothelial cells (BAECs), respectively, which was attenuated by Res treatment. Application of Res reversed the changes in eNOS and Cav-1 expressions in aorta and heart of rats fed HFS and in BAECs incubated with high glucose. Res stimulated the formation of NO inhibited by high glucose in BAECs. Beta-Cyclodextrin (β-CD), caveolae inhibitor, showed the better beneficial effect than Res alone to up-regulate eNOS phosphorylative levels, while NG-Nitro-77 L-arginine methyl ester (L-NAME), eNOS inhibitor, had no effect on Cav-1 expression. Our studies suggested that HFS and in vitro treatment with high glucose caused endothelial hyperpermeability, which were ameliorated by Res at least involving Cav-1/eNOS regulation.

  2. Binding mechanisms of 1,4-dihydropyridine derivatives to L-type calcium channel Cav1.2: a molecular modeling study.

    PubMed

    Xu, Lei; Li, Dan; Tao, Li; Yang, Yanling; Li, Youyong; Hou, Tingjun

    2016-02-01

    L-type Ca(2+) channels (LTCCs), the heteromultimeric proteins, are associated with electrical signaling and provide the key link between electrical signals and non-electrical processes. 1,4-Dihydropyridine (DHP) derivatives are a major class of blockers for LTCCs, and have experienced widespread use in the treatment of cardiovascular diseases. However, the precise knowledge of the binding mechanism of these ligands to LTCCs at the atomic level has remained unknown because of the unavailability of the crystal structures of LTCCs. In this study, homology modeling, molecular docking, molecular dynamics (MD) simulations, free energy calculations and decomposition were employed to explore the structural requirement of the binding of DHP derivatives to human Cav1.2, a member of LTCCs. The binding conformations of the DHPs in the active site of Cav1.2 were predicted, and the rank of the binding free energies of Cav1.2/DHPs is generally consistent with the experimental data. The structural analysis shows that most studied ligands fit into a hydrophobic pocket formed by Phe1129, Ile1173, Phe1176, Met1177 and Met1509, and form aryl-aryl interaction with Phe1129 or Tyr1508. The consistency between the predictions and experimental data suggest that the developed model is reliable and can be used as a valuable platform for the structure-based design of new potent ligands of Cav1.2.

  3. Electrophysiological evidence for voltage-gated calcium channel 2 (Cav2) modulation of mechano- and thermosensitive spinal neuronal responses in a rat model of osteoarthritis

    PubMed Central

    Rahman, W.; Patel, R.; Dickenson, A.H.

    2015-01-01

    Osteoarthritis (OA) remains one of the greatest healthcare burdens in western society, with chronic debilitating pain-dominating clinical presentation yet therapeutic strategies are inadequate in many patients. Development of better analgesics is contingent on improved understanding of the molecular mechanisms mediating OA pain. Voltage-gated calcium channels 2.2 (Cav2.2) play a critical role in spinal nociceptive transmission, therefore blocking Cav2.2 activity represents an attractive opportunity for OA pain treatment, but the only available licensed Cav2.2 antagonist ziconitide (PrilatTM) is of limited use. TROX-1 is an orally available, use dependent and state-selective Cav2 antagonist, exerting its analgesic effect primarily via Cav2.2 blockade, with an improved therapeutic window compared with ziconitide. Using a rat model of monosodium iodoacetate (MIA), 2 mg, induced OA we used in vivo electrophysiology to assess the effects of spinal or systemic administration of TROX-1 on the evoked activity of wide dynamic range spinal dorsal horn neurons in response to electrical, natural mechanical (dynamic brush and von Frey 2, 8, 26 and 6 g) and thermal (40, 45 and 45 °C) stimuli applied to the peripheral receptive field. MIA injection into the knee joint resulted in mechanical hypersensitivity of the ipsilateral hind paw and weight-bearing asymmetry. Spinal administration of TROX-1 (0.1 and 1 μg/50 μl) produced a significant dose-related inhibition of dynamic brush, mechanical (von Frey filament (vF) 8, 26 and 60 g) and noxious thermal-(45 and 48 °C) evoked neuronal responses in MIA rats only. Systemic administration of TROX-1 produced a significant inhibition of the mechanical-(vF 8, 26 and 60 g) evoked neuronal responses in MIA rats. TROX-1 did not produce any significant effect on any neuronal measure in Sham controls. Our in vivo electrophysiological results demonstrate a pathological state-dependent effect of TROX-1, which suggests an increased