This is the first successful report on selenium bio-attenuation to satisfy drinking water regulations as per Indian Standards (10 μg/L) in the presence of concomitant nitrate and sulfate from water sources utilizing a fixed bed bioreactor. The bioreactor was immunized with blended microbial culture and worked in downflow mode under anoxic conditions at 30 ± 2 °C for around 190 days under varying influent selenate (100-500 μg/L as selenium), nitrate (50 mg/L), sulfate concentrations (as per selenium removal) and necessary dose of acetic acid (as COD, a carbon source) in synthetic groundwater, operated at an empty bed contact time (EBCT) of 45-120 min. After supplying an adequate dosage of sulfate and alteration of EBCT, selenium was found to comply with drinking water regulations and nitrate was completely removed.
View Article and Find Full Text PDFEye diseases characterized by excessive angiogenesis such as wet age-related macular degeneration, proliferative diabetic retinopathy, and retinopathy of prematurity are major causes of blindness. Cremastranone is an antiangiogenic, naturally occurring homoisoflavanone with efficacy in retinal and choroidal neovascularization models and antiproliferative selectivity for endothelial cells over other cell types. We undertook a cell-based structure-activity relationship study to develop more potent cremastranone analogues, with improved antiproliferative selectivity for retinal endothelial cells.
View Article and Find Full Text PDFGenomic studies of the pediatric ocular tumor retinoblastoma are paving the way for development of targeted therapies. Robust model systems such as orthotopic xenografts are necessary for testing such therapeutics. One system involves bioluminescence imaging of luciferase-expressing human retinoblastoma cells injected into the vitreous of newborn rat eyes.
View Article and Find Full Text PDFRetinopathies in human and animal models have shown to occur through loss of pericytes resulting in edema formation, excessive immature retinal angiogenesis, and neuronal apoptosis eventually leading to blindness. In recent years, the concept of regenerating terminally differentiated organs with a cell-based therapy has evolved. The cells used in these approaches are diverse and include tissue-specific endogenous stem cells, endothelial progenitor (EPC), embryonic stem cells, induced pluripotent stem cells (iPSC) and mesenchymal stem cells (MSC).
View Article and Find Full Text PDFPreventing pathological ocular angiogenesis is key to treating retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration. At present there is no small molecule drug on the market to target this process and hence there is a pressing need for developing novel small molecules that can replace or complement the present surgical and biologic therapies for these neovascular eye diseases. Previously, an antiangiogenic homoisoflavanone was isolated from the bulb of a medicinal orchid, Cremastra appendiculata.
View Article and Find Full Text PDFTNF-α induces loss of barrier integrity of the corneal endothelium through mechanisms involving the activation of p38 MAP kinase. This study has investigated the role of matrix metalloproteinase-9 (MMP-9), known to be activated by mechanisms downstream of p38 MAP kinase, on the breakdown of the barrier integrity. Experiments were performed with primary cultures of bovine corneal endothelium.
View Article and Find Full Text PDFDiabetic retinopathy (DR) is the leading cause of blindness in working-age adults. Early stage DR involves inflammation, vascular leakage, apoptosis of vascular cells and neurodegeneration. In this study, we hypothesized that cells derived from the stromal fraction of adipose tissue (ASC) could therapeutically rescue early stage DR features.
View Article and Find Full Text PDFAm J Respir Cell Mol Biol
December 2012
Endothelial monocyte-activating polypeptide II (EMAP II) and interferon-inducible protein (IP)-10 are proinflammatory mediators, which in addition to their chemokine activities, selectively induce apoptosis in endothelial cells and are up-regulated in the lungs of cigarette smoke-exposed humans. Previously, we showed that EMAP II is an essential mediator of cigarette smoke-induced lung emphysema in mice linking endothelial cell apoptosis with inflammation. Here we addressed the role of the CXCR3 receptor in EMAP II-induced and IP-10-induced apoptosis in endothelial cells and its regulation by cigarette smoke.
View Article and Find Full Text PDFBackground: Recent clinical trials indicate that human adipose-derived stromal cells (hASCs) have beneficial effects on antiaging and wound healing. This study examined the morphologic changes in photodamaged human organotypic skin culture after treatment of autologous hASCs.
Methods: Abdominal skin flaps were obtained from 8 white females who underwent abdominoplasties with liposuction.
AIDS Res Hum Retroviruses
October 2012
Untreated HIV infection is associated with endothelial dysfunction and subsequent cardiovascular disease, likely due to both direct effects of the virus and to indirect effects of systemic inflammation on the vasculature. We have recently shown that treatment with the antiinflammatory agent pentoxifylline (PTX) improved in vivo endothelial function and reduced circulating levels of the inflammatory markers vascular cell adhesion molecule-1 (VCAM-1) and interferon-gamma-induced protein (IP-10) in HIV-infected patients. To delineate the mechanisms underlying this therapeutic effect, we tested whether clinically relevant concentrations of PTX suppress VCAM-1 or IP-10 release in cultivated human lung microvascular endothelial cells.
View Article and Find Full Text PDFChronic kidney disease pathogenesis involves both tubular and vascular injuries. Despite abundant investigations to identify the risk factors, the involvement of chronic endothelial dysfunction in developing nephropathies is insufficiently explored. Previously, soluble thrombomodulin (sTM), a cofactor in the activation of protein C, has been shown to protect endothelial function in models of acute kidney injury.
View Article and Find Full Text PDFPulmonary emphysema is a disease characterized by alveolar cellular loss and inflammation. Recently, excessive apoptosis of structural alveolar cells has emerged as a major mechanism in the development of emphysema. Here, we investigated the proapoptotic and monocyte chemoattractant cytokine endothelial monocyte-activating protein 2 (EMAPII).
View Article and Find Full Text PDFChronic inflammation is tightly linked to diseases associated with endothelial dysfunction including aberrant angiogenesis. To better understand the endothelial role in pro-inflammatory angiogenesis, we analyzed signaling pathways in continuously activated endothelial cells, which were either chronically exposed to soluble TNF or the reactive oxygen species (ROS) generating H2O2, or express active transmembrane TNF. Testing in an in vitro capillary sprout formation assay, continuous endothelial activation increased angiogenesis dependent on activation of p38 MAP kinase, NADPH oxidase, and matrix metalloproteinases (MMP).
View Article and Find Full Text PDFAm J Respir Crit Care Med
February 2010
Rationale: Vascular endothelial growth factor receptor (VEGFR) inhibition increases ceramides in lung structural cells of the alveolus, initiating apoptosis and alveolar destruction morphologically resembling emphysema. The effects of increased endogenous ceramides could be offset by sphingosine 1-phosphate (S1P), a prosurvival by-product of ceramide metabolism.
Objectives: The aims of our work were to investigate the sphingosine-S1P-S1P receptor axis in the VEGFR inhibition model of emphysema and to determine whether stimulation of S1P signaling is sufficient to functionally antagonize alveolar space enlargement.
Invest Ophthalmol Vis Sci
March 2010
Purpose: TNF-alpha is elevated in the cornea and aqueous humor during allograft rejection and anterior uveitis. The authors investigated the involvement of p38 MAP kinase in the TNF-alpha-induced loss of barrier integrity in monolayers of cultured bovine corneal endothelial cells.
Methods: Transendothelial electrical resistance (TER), a measure of barrier integrity, was determined by electrical cell-substrate impedance sensing.
EMAP II is an endothelial cell and monocyte activating proinflammatory cytokine, which has been demonstrated to induce endothelial cell apoptosis. In order to analyze its role in disease models linked to inflammation and endothelial cell death, we aimed to develop a neutralizing antibody against mouse EMAP II. Therefore, we generated rat monoclonal anti-mouse EMAP II antibodies by immunization with recombinant full length, mouse pro-EMAP II protein.
View Article and Find Full Text PDFSenescence of endothelial cells increases with systemic aging and is thought to contribute to the development of atherosclerosis. Cell therapy with highly proliferative endothelial progenitor cells (EPCs) is an emerging therapeutic option to promote endothelial regeneration, but little is known about their senescence and their vulnerability to inflammatory stressors. We therefore studied the senescence of proliferative human EPCs and investigated the effects of the proinflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) on their senescence.
View Article and Find Full Text PDFAlthough the roles of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and hepatocyte growth factor (HGF) in pathologic neovascularization have been well characterized in certain tissues, their particular functions and expression patterns in choroidal neovascularization (CNV) have not been clearly established. After localized laser trauma to Bruch's membrane to induce CNV development, the temporal changes in mRNA and protein expression of these 3 cytokines were documented and compared histologically to areas of immunofluorescence, the proliferation of endothelial cells, neovascular development, and temporal changes in vascular permeability. Changes in mRNA and protein levels of bFGF and HGF occurred quickly and reached peak expression within hours.
View Article and Find Full Text PDFAdipose stromal cells (ASC) are multipotential mesenchymal progenitor cells that are readily induced to undergo adipogenic differentiation, and we have recently demonstrated them to have functional and phenotypic overlap with pericytes lining microvessels in adipose tissues. In this study we addressed the hypothesis that modulation of ASC fate within this perivascular niche can occur via interaction with endothelial cells (EC), which serve to modulate the adipogenic potential of ASC. To this end, we investigated contact as well as paracrine effects of EC on ASC adipogenesis, in two-dimensional coculture and via conditioned medium and analyzed mutual gene expression changes by real-time reverse transcription polymerase chain reaction (PCR).
View Article and Find Full Text PDFActivation of the vascular endothelium with cytokines such as TNF is widely used to study the role of the vasculature in proinflammatory disease. To gain insight into mechanisms of prolonged vascular endothelial activation we compared changes in gene expression induced by continuous activation in stable tmTNF-expressing cells with changes due to acute TNF challenge in vitro. Affymetrix Genechip analysis was performed on RNA from control, acute and continuous TNF-activated endothelial cells.
View Article and Find Full Text PDFThe reproductive toxicity of curcumin, turmeric yellow, in Wistar rats was studied in order to generate additional relevant toxicity information for the use of curcumin in humans by oral administration. The two generation reproduction study was designed and conducted in accordance with OECD Guideline No. 416 [OECD, 1983.
View Article and Find Full Text PDFObjective: Recruitment of endothelial progenitor cells to the sites of ischemia has recently been suggested as a mechanism of tissue repair. Here we address the hypothesis that the hypoxia-inducible full-length endothelial-monocyte-activating polypeptide II (EMAP II) provides a mechanism to recruit late outgrowth highly proliferating endothelial progenitor cells (EPCs).
Materials And Methods: We tested in a transwell migration assay EMAP II for its ability to induce migration of EPCs.
There is increasing evidence that chronic inflammation is tightly linked to diseases associated with endothelial dysfunction, including the induction of aberrant angiogenesis. While leukocytes have been described as mediators of inflammation-associated angiogenesis, the effects of direct chronic endothelial activation have not been addressed in this context. Using an uncleavable mutant of the transmembrane form of tumor necrosis factor-alpha (TNF-alpha), we have established models of stable TNF-alpha expression in endothelial cells in vitro and in transgenic mice in vivo.
View Article and Find Full Text PDFKnowledge of the rapidly developing hierarchy of controls affecting vascular development in placenta is required to understand how the growth factors and their receptor-mediated signals actually produce vessels. At the cell biological level, these events clearly require stable interactions between the cells, and cells with the surrounding ECM. The objective of the study was to understand the role of integrins and ECM on the expression and secretion of angiogenin in placentas and from trophoblasts in culture.
View Article and Find Full Text PDFObjective: Many processes that are involved in cellular invasion, including blastocyst implantation, placental development, and rapidly growing tumors, occur in reduced oxygen environments. It has been surmised that oxygen tension could regulate the cytotrophoblast ability to differentiate and, as a consequence, to express proteins that are critical for placentation. The objective of the current investigation was therefore to test the hypothesis that placental tissues and trophoblast cells in culture, under low oxygen tension, release angiogenic factors that could affect vascular behavior and invasive potential, thus providing a link between abnormal placentation and maternal vascular abnormality.
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