Potential benefits of melatonin in organ transplantation: a review

Organ transplantation is a useful therapeutic tool for patients with end-stage organ failure; however, graft rejection is a major obstacle in terms of a successful treatment. Rejection is usually a consequence of a complex immunological and nonimmunological antigen-independent cascade of events, including free radical-mediated ischemia-reperfusion injury (IRI). To reduce the frequency of this outcome, continuing improvements in the efficacy of antirejection drugs are a top priority to enhance the long-term survival of transplant recipients. Melatonin (N-acetyl-5-methoxytryptamine) is a powerful antioxidant and ant-inflammatory agent synthesized from the essential amino acid L-tryptophan; it is produced by the pineal gland as well as by many other organs including ovary, testes, bone marrow, gut, placenta, and liver. Melatonin has proven to be a potentially useful therapeutic tool in the reduction of graft rejection. Its benefits are based on its direct actions as a free radical scavenger as well as its indirect antioxidative actions in the stimulation of the cellular antioxidant defense system. Moreover, it has significant anti-inflammatory activity. Melatonin has been found to improve the beneficial effects of preservation fluids when they are enriched with the indoleamine. This article reviews the experimental evidence that melatonin is useful in reducing graft failure, especially in cardiac, bone, otolaryngology, ovarian, testicular, lung, pancreas, kidney, and liver transplantation

Shallow crustal structure of the junction of the grabens of Chapala, Tepic-Zacoalco and Colima, Mexico

Gravity data is used to infer the shallow crustal structure of the Tepic graben adjacent to the City of Guadalajara. This depression does not constitute a symmetric graben with steep master faults but rather a complex transition zone. Blocks detached from the granitic sierras are downfaulted and tilted to the northeast along the frong of these sierras. Farther to the north, the granitic basement deepens gradually. However, it steepens at the limit between the Sierra Madre Occidental and the Jalisco Block. Northwest of our study area, the limit is located north of the Plan de Barrancas fault. At the east the limit is located closer to the southward prolongation of the Plan de Barrancas fault. The change in position occurs near La Primavera caldera. The La Primavera caldera, Tequila volcano, and vents of cinder and lava cones are emplaced along NW-SE weakness zones in the batholith. The crust of the Sierra Madre Occidental adjacent to the limit features NE-SW lineaments perpendicular to those of the neighbouring Jalisco Block (JB)

Vulnerability to contamination of the Zaachila aquifer, Oaxaca, Mexico

The aquifer of Zaachila was evaluated following conventional methods (DRASTIC, AVI, and GOD). Depth to the water table was established from a set of wells. Accordingly, the groundwater flows from N to S. Hydraulic conductivity ranges between 1.81647E-05 and 1.70411E-04 m/s, while transmissivity varies between 22.01 and 220.85 m2/day. The net mean annual recharge was estimated at 98 mm/year. The aquifer is constituted mainly by sand, gravel and clay. The soil cover is up to 1.5 m thick and is constituted by lime, clay and sandy material. According to GOD, some zones of this aquifer have a medium to high vulnerability. DRASTIC assigns a high vulnerability to large part of the area. The highest values are observed in the southern and middle sections, from Oaxaca city to the south including San Bartolo Coyotepec, as well as Zaachila town and airport. The AVI method assigns to the valley a high to very high vulnerability. A sensitivity analysis suggests that depth to water table is the key factor determining vulnerability, followed by impact to the vadose zone and soil type

On optimal location and management of a new industrial plant: Numerical simulation and control

There are several areas in Central Mexico with subsidence troubles, such as Aguascalientes, Celaya, Queretaro and Morelia. For 20 years, Ameca town located in Jalisco State, Mexico, has been affected by slow subsidence. The Plio-Quaternary tectonic framework for western-central Mexico suggests a NW fault system associated with a NE-extension. The Ameca region is in this environment. When the damages (e.g cracked houses) are located on a map they show a W-NW trend similar to the regional faulting. Geological studies show that the main normal fault is 4 km long with a 7 m vertical offset. The electrical resistivity tomography study shows that recent sediments are affected by fractures with the same trend as the main normal fault. Copyright " 2010 IAHS Press.",,,,,,,,,"http://hdl.handle.net/20.500.12104/41752","http://www.scopus.com/inward/record.url?eid=2-s2.0-79952653701&partnerID=40&md5=6ee1e4d8338d5c2f6b4f380de5c6994c",,,,,,,,"IAHS-AISH Publication",,"19

Geological study and electrical resistivity tomography of Ameca, Jalisco, Mexico

There are several areas in Central Mexico with subsidence troubles, such as Aguascalientes, Celaya, Queretaro and Morelia. For 20 years, Ameca town located in Jalisco State, Mexico, has been affected by slow subsidence. The Plio-Quaternary tectonic framework for western-central Mexico suggests a NW fault system associated with a NE-extension. The Ameca region is in this environment. When the damages (e.g cracked houses) are located on a map they show a W-NW trend similar to the regional faulting. Geological studies show that the main normal fault is 4 km long with a 7 m vertical offset. The electrical resistivity tomography study shows that recent sediments are affected by fractures with the same trend as the main normal fault. Copyright © 2010 IAHS Press

Interpretation of gravity profiles across the northern Oaxaca terrane, its boundaries and the Tehuacán Valley, southern Mexico

A gravity study was conducted across the northern Oaxaca terrane and its bounding faults: the Caltepec and Oaxaca Faults to the west and east, respectively. These faults juxtapose the Oaxaca terrane against the Mixteca and Juarez terranes, respectively. The Oaxaca Fault also forms the eastern boundary of the Cenozoic Tehuacán depression. On the west, at depth, the Tehuacán valley is limited by the normal buried Tehuacán Fault. This gravity study reveals that the Oaxaca Fault system gives rise to a series of east tilted basamental blocks (Oaxaca Complex). The tectonic depression is filled with Phanerozoic rocks and has a deeper depocenter to the west. The gravity data also indicate that on the west, the Oaxaca Complex, the Caltepec and Santa Lucia faults continue northwestwards beneath Phanerozoic rocks. A major E-W to NE-SW discontinuity is inferred to exist between profiles 1 and 2. © 2014 Elsevier Ltd

Intraguild predation on the whitefly parasitoid eretmocerus eremicus by the generalist predator geocoris punctipes: A behavioral approach

A gravity study was conducted across the northern Oaxaca terrane and its bounding faults: the Caltepec and Oaxaca Faults to the west and east, respectively. These faults juxtapose the Oaxaca terrane against the Mixteca and Juarez terranes, respectively. The Oaxaca Fault also forms the eastern boundary of the Cenozoic Tehuacán depression. On the west, at depth, the Tehuacán valley is limited by the normal buried Tehuacán Fault. This gravity study reveals that the Oaxaca Fault system gives rise to a series of east tilted basamental blocks (Oaxaca Complex). The tectonic depression is filled with Phanerozoic rocks and has a deeper depocenter to the west. The gravity data also indicate that on the west, the Oaxaca Complex, the Caltepec and Santa Lucia faults continue northwestwards beneath Phanerozoic rocks. A major E-W to NE-SW discontinuity is inferred to exist between profiles 1 and 2. " 2014 Elsevier Ltd.",,,,,,"10.1016/j.jsames.2014.09.020",,,"http://hdl.handle.net/20.500.12104/42339","http://www.scopus.com/inward/record.url?eid=2-s2.0-84921911977&partnerID=40&md5=19f002b473bbe8dae489966860b562a3",,,,,,,,"Journal of South American Earth Sciences",,"39

The use of a rotating cylinder electrode to selective recover palladium from acid solutions used to manufacture automotive catalytic converters

The reduction of palladium, rhodium and neodymium ions at concentrations of 0.94, 0.97 and 0.69 mol dm-3, respectively was studied in 1 mol dm-3 HNO3 or 1 mol dm-3 HCl, at a stainless steel and a vitreous carbon electrode, at 25 ºC. At a vitreous carbon electrode in a solution containing rhodium and palladium ions in 1 mol dm-3 HCl electrolyte, the reduction of metal ions occurred at a similar potential to the formation of hydrogen gas, which impeded selective separation of the two metals. At a stainless steel cathode in 1 mol dm-3 HNO3, palladium deposition occurred at a potential ? 0.35 V less negative than that of rhodium allowing the selective recovery of palladium. Neodymium ions were not electroactive in acidic chloride or nitrate media at pH 0. Using a solution obtained from a catalytic converter manufacturer containing palladium, rhodium and neodymium ions in 1 mol dm-3 HNO3, palladium ions were preferentially removed at 0.15 V vs. SHE at an average cumulative current efficiency of 57

Effect of the substrate on the properties of ZnO-MgO thin films grown by atmospheric pressure metal-organic chemical vapor deposition

The ZnO-MgO alloys possess attractive properties for possible applications in optoelectronic and display devices; however, the optical properties are strongly dependent on the deposition parameters. In this work, the effect of the glassy and metallic substrates on the structural, morphological and optical properties of ZnO-MgO thin films using atmospheric pressure metal-organic chemical vapor deposition was investigated at relatively low deposition temperature, 500 °C. Magnesium and zinc acetylacetonates were used as the metal-organic source. X-ray diffraction experiments provided evidence that the kind of substrates cause a deviation of c-axis lattice constant due to the constitution of a oxide mixture (ZnO and MgO) in combination with different intermetallic compounds(Mg 2Zn 11 and Mg 4Zn 7) in the growth films. The substitutional and interstitial sites of Mg 2+ instead of Zn 2+ ions in the lattice are the most probable mechanism to form intermetallic compounds. The optical parameters as well as thickness of the films were calculated by Spectroscopic Ellipsometry using the classical dispersion model based on the sum of the single and double Lorentz and Drude oscillators in combination with Kato-Adachi equations, as well as X-ray reflectivity. © 2011 Elsevier B.V. All rights reserved

A comparison of the electrochemical recovery of palladium using a flat plate flow-by reactor and a rotating cylinder electrode reactor

The production of catalytic converters generates large amounts of waste water containing Pd2+, Rh3+ and Nd3+ ions. The electrochemical treatment of these solutions offers an economic and effective alternative to recover the precious metals in comparison with other traditional metal recovery technologies. The separation of palladium from this mixture of metal ions by catalytic deposition was carried out using a rotating cylinder electrode reactor (RCER) and a parallel plate reactor (FM01-LC) with the same cathode area (64 cm2) and electrolyte volume (300 cm3). The study was carried out at mean linear flow velocities of 1.27 < v < 11.36 cm s?1 (120 < Re = vde/v < 1080) for the FM01-LC reactor and 20 < v < 140 cm s?1 (7390 < Re = vd/v < 51,700) for the RCER. The morphology of the palladium deposits at the entrance and at the exit of the electrolyte compartment of the FM01-LC reactor showed the effect of the manifold distributors during the electrolysis; the manifolds generate micro turbulences, increasing the mass transport coefficient in these areas and favouring rapid recovery of palladium ions. More uniform high purity palladium deposits were obtained on the surface of the RCER. The cumulative current efficiency to recover 99% of Pd2+ ions in the parallel plate electrode reactor was 35% while the recovery of 97% of Pd2+ in the RCER was 62%. The volumetric energy consumption during the electrolysis was 0.56 kW h m?3 and 2.1 kW h m?3 for the RCER and the FM01-LC reactors, respectively. Using a three-dimensional stainless steel electrode in the FM01-LC laboratory reactor, 99% of palladium ions were recovered after 30 min of electrolysis while in the RCER, 120 min were necessary