Adsorption of Dicamba herbicide onto a carbon replica obtained from a layered double hydroxide.

In this work, a carbon replica derived from a vinylbenzenesulfonate-intercalated layered double hydroxide (CR-LDH) was applied to remove the Dicamba organochlorine herbicide from aqueous solution. The samples were characterized by several experimental techniques such as X-ray diffraction (XRD), thermogravimetric analysis coupled with differential scanning calorimetry and mass spectrometry (TGA-DSC-MS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), Raman spectroscopy, N2 adsorption/desorption and zeta potential analysis. The CR-LDH sample presents a very high specific surface area (2345 m2 g-1). The adsorption experiment typically followed the Langmuir isotherm model and the adsorption kinetics was best fitted with a pseudo second-order model. The maximum adsorption capacity of Dicamba herbicide onto CR-LDH was 279 mg g-1. CR-LDH presented a higher adsorption capacity than other carbon adsorbent materials reported in the literature.

Nicotine-induced plasticity in the retinocollicular pathway: Evidence for involvement of amyloid precursor protein.

During early postnatal development retinocollicular projections undergo activity-dependent synaptic refinement that results in the formation of precise topographical maps in the visual layers of the superior colliculus (SC). Amyloid Precursor Protein (APP) is a widely expressed transmembrane glycoprotein involved in the regulation of several aspects of neural development, such as neurite outgrowth, synapse formation and plasticity. Stimulation of cholinergic system has been found to alter the expression and processing of APP in different cell lines. Herein, we investigated the effect of nicotine on the development of retinocollicular pathway and on APP metabolism in the SC of pigmented rats. Animals were submitted to intracranial Elvax implants loaded with nicotine or phosphate-buffered saline (vehicle) at postnatal day (PND) 7. The ipsilateral retinocollicular pathway of control and experimental groups was anterogradely labeled either 1 or 3 weeks after surgery (PND 14 or PND 28). Local nicotine exposure produces a transitory sprouting of uncrossed retinal axons outside their main terminal zones. Nicotine also increases APP content and its soluble neurotrophic fragment sAPPα. Furthermore, nicotine treatment upregulates nicotinic acetylcholine receptor α7 and ß2 subunits. Taken together, these data indicate that nicotine disrupts the ordering and topographic mapping of axons in the retinocollicular pathway and facilitates APP processing through the nonamyloidogenic pathway, suggesting that sAPPα may act as a trophic agent that mediates nicotine-induced morphological plasticity.

Dermatan sulfate reduces monocyte chemoattractant protein 1 and TGF-ß production, as well as macrophage recruitment and myofibroblast accumulation in mice with unilateral ureteral obstruction.

Selectins play an essential role in most inflammatory reactions, mediating the initial leukocyte-rolling event on activated endothelium. Heparin and dermatan sulfate (DS) bind and block P- and L-selectin function in vitro. Recently, we reported that subcutaneous administration of DS inhibits colon inflammation in rats by reducing macrophage and T-cell recruitment and macrophage activation. In the present study, we examined the effect of porcine intestinal mucosa DS on renal inflammation and fibrosis in mice after unilateral ureteral obstruction (UUO). Twenty-four adult male Swiss mice weighing 20-25 g were divided into 4 groups: group C (N = 6) was not subjected to any surgical manipulation; group SH (N = 6) was subjected to surgical manipulation but without ureter ligation; group UUO (N = 6) was subjected to unilateral ureteral obstruction and received no treatment; group UUO plus DS (N = 6) was subjected to UUO and received DS (4 mg/kg) subcutaneously daily for 14 days. An immunoblot study was also performed for TGF-ß. Collagen (stained area ~3700 µm(2)), MCP-1 (stained area ~1700 µm(2)), TGF-ß (stained area ~13% of total area), macrophage (number of cells ~40), and myofibroblast (stained area ~1900 µm(2)) levels were significantly (P < 0.05) higher in the UUO group compared to control. DS treatment significantly (P < 0.05) reduced the content of collagen (stained area ~700 µm(2)), MCP-1 (stained area ~160 µm(2)) and TGF-ß (stained area ~5% of total area), in addition to myofibroblast (stained area ~190 µm(2)) and macrophage (number of cells ~32) accumulation in the obstructed kidney. Overall, these results indicate that DS attenuates kidney inflammation by reducing macrophage recruitment, myofibroblast population and fibrosis in mice submitted to UUO.

Dermatan sulfate reduces monocyte chemoattractant protein 1 and TGF-β production, as well as macrophage recruitment and myofibroblast accumulation in mice with unilateral ureteral obstruction

Selectins play an essential role in most inflammatory reactions, mediating the initial leukocyte-rolling event on activated endothelium. Heparin and dermatan sulfate (DS) bind and block P- and L-selectin function in vitro. Recently, we reported that subcutaneous administration of DS inhibits colon inflammation in rats by reducing macrophage and T-cell recruitment and macrophage activation. In the present study, we examined the effect of porcine intestinal mucosa DS on renal inflammation and fibrosis in mice after unilateral ureteral obstruction (UUO). Twenty-four adult male Swiss mice weighing 20-25 g were divided into 4 groups: group C (N = 6) was not subjected to any surgical manipulation; group SH (N = 6) was subjected to surgical manipulation but without ureter ligation; group UUO (N = 6) was subjected to unilateral ureteral obstruction and received no treatment; group UUO plus DS (N = 6) was subjected to UUO and received DS (4 mg/kg) subcutaneously daily for 14 days. An immunoblot study was also performed for TGF-β. Collagen (stained area ~3700 µm²), MCP-1 (stained area ~1700 µm²), TGF-β (stained area ~13 percent of total area), macrophage (number of cells ~40), and myofibroblast (stained area ~1900 µm²) levels were significantly (P < 0.05) higher in the UUO group compared to control. DS treatment significantly (P < 0.05) reduced the content of collagen (stained area ~700 µm²), MCP-1 (stained area ~160 µm²) and TGF-β (stained area ~5 percent of total area), in addition to myofibroblast (stained area ~190 µm²) and macrophage (number of cells ~32) accumulation in the obstructed kidney. Overall, these results indicate that DS attenuates kidney inflammation by reducing macrophage recruitment, myofibroblast population and fibrosis in mice submitted to UUO.

New material for low-dose brachytherapy seeds: Xe-doped amorphous carbon films with post-growth neutron activated 125I.

We report a novel material for use in (125)I brachytherapy that consists of amorphous carbon films grown by ion-beam-assisted deposition and doped with Xe (5 at%) by implantation. Samples of these films grown on Si substrates were irradiated with neutrons in a TRIGA-I nuclear reactor for the production (125)Xe, and latter characterized by gamma spectroscopy. The results indicate that the (124)Xe was efficiently converted into (125)Xe, the precursor of (125)I, and support the activity calculations for a model brachytherapy seed.

The role of purinergic P2X7 receptors in the inflammation and fibrosis of unilateral ureteral obstruction in mice.

Receptors of the P2X7 type have been demonstrated in granulocytes, monocytes/macrophages, B and T lymphocytes, and have been involved in several cellular mechanisms including those related to inflammation and immunological response. This study attempted to investigate the role of these receptors on the inflammatory and fibrogenic response in the kidneys of unilateral ureteral obstruction (UUO), by using P2X7 knockout mice (-/-). C57Bl6 mice were submitted to left UUO and killed after 7 and 14 days. Histopathology using hematoxylin-eosin, periodic-acid Schiff and Sirius-red staining, immunohistochemistry for macrophages, myofibroblasts, transforming growth factor-beta (TGF-beta)1 and P2X7, and immunofluorescence for apoptotic cells (terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate nick-end labeling) were performed. Protocols were as follows: (1) control; (2) sham; (3) control P2X7 (-/-); (4) sham P2X7 (-/-); (5) UUO wild type (WT); (6) UUO P2X7 (-/-). Myofibroblasts and Sirius-red staining were significantly lower in UUO P2X7 (-/-) mice at days 7 and 14, compared to UUO WT. Kidneys from UUO P2X7 (-/-) mice showed reduced number of inflammatory cells at day 14 but not at day 7, compared to UUO WT. TGF-beta1 was less in UUO P2X7 (-/-) mice at days 7 and 14 when compared to UUO WT. Macrophage infiltration and tubular apoptosis were lower in UUO P2X7 (-/-) at day 14 but not at day 7, compared to UUO WT. P2X7 was expressed only in tubular epithelial cells at day 7 of UUO WT mice. These findings constitute the first evidence that P2X7 receptors are implicated in macrophage infiltration, collagen deposition and apoptosis in response to ureteral obstruction in mice.