140 research outputs found
Toxicity abatement of wastewaters from tourism units by constructed wetlands
The present research intended to investigate the toxicity abatement of domestic wastewater after passing a biosystem composed of a constructed wetland (CW) followed by a pond. The wastewater was generated in a tourism house in a rural and mountainous context and passed through a septic tank before being diverted to a CW followed by a pond. A battery of ecotoxicological tests, comprising microalgae (Raphidocelis subcapitata), macrophytes (Lemna minor), cladocerans (Daphnia magna), and bacteria (Aliivibrio fischeri), was used to assess the toxicity of the wastewater collected before and after the CW and the water of the pond. Physicochemical parameters (pH, conductivity, chemical oxygen demand, biochemical oxygen demand, total suspended solids, phosphates, ammonium, and nitrate) were also determined. The CW was able to remove carbon and nutrients from the water with a concomitant reduction of its toxicity. This study, reinforced the added value of using toxicity tests as a complement to CW operational monitoring to validate the solution and to analyze possible readjustments that may be required to improve efficiency. This study lends further support to the claim that CWs can be a sustainable solution for treating small volumes of domestic wastewater in a rural context.info:eu-repo/semantics/publishedVersio
Induction of neurotrophin expression via human adult mesenchymal stem cells: implication for cell therapy in neurodegenerative diseases.
In animal models of neurological disorders for cerebral ischemia, Parkinson's disease, and spinal cord lesions, transplantation of mesenchymal stem cells (MSCs) has been reported to improve functional outcome. Three mechanisms have been suggested for the effects of the MSCs: transdifferentiation of the grafted cells with replacement of degenerating neural cells, cell fusion, and neuroprotection of the dying cells. Here we demonstrate that a restricted number of cells with differentiated astroglial features can be obtained from human adult MSCs (hMSCs) both in vitro using different induction protocols and in vivo after transplantation into the developing mouse brain. We then examined the in vitro differentiation capacity of the hMSCs in coculture with slices of neonatal brain cortex. In this condition the hMSCs did not show any neuronal transdifferentiation but expressed neurotrophin low-affinity (NGFRp75) and high-affinity (trkC) receptors and released nerve growth factor (NGF) and neurotrophin-3 (NT-3). The same neurotrophin's expression was demonstrated 45 days after the intracerebral transplantation of hMSCs into nude mice with surviving astroglial cells. These data further confirm the limited capability of adult hMSC to differentiate into neurons whereas they differentiated in astroglial cells. Moreover, the secretion of neurotrophic factors combined with activation of the specific receptors of transplanted hMSCs demonstrated an alternative mechanism for neuroprotection of degenerating neurons. hMSCs are further defined in their transplantation potential for treating neurological disorders
Effect of human skin-derived stem cells on vessel architecture, tumor growth, and tumor invasion in brain tumor animal models
Glioblastomas represent an important cause of cancer-related mortality with poor survival. Despite many advances, the mean survival time has not significantly improved in the last decades. New experimental approaches have shown tumor regression after the grafting of neural stem cells and human mesenchymal stem cells into experimental intracranial gliomas of adult rodents. However, the cell source seems to be an important limitation for autologous transplantation in glioblastoma. In the present study, we evaluated the tumor targeting and antitumor activity of human skin-derived stem cells (hSDSCs) in human brain tumor models. The hSDSCs exhibit tumor targeting characteristics in vivo when injected into the controlateral hemisphere or into the tail vein of mice. When implanted directly into glioblastomas, hSDSCs distributed themselves extensively throughout the tumor mass, reduced tumor vessel density, and decreased angiogenic sprouts. In addition, transplanted hSDSCs differentiate into pericyte cell and release high amounts of human transforming growth factor-beta1 with low expression of vascular endothelial growth factor, which may contribute to the decreased tumor cell invasion and number of tumor vessels. In long-term experiments, the hSDSCs were also able to significantly inhibit tumor growth and to prolong animal survival. Similar behavior was seen when hSDSCs were implanted into two different tumor models, the chicken embryo experimental glioma model and the transgenic Tyrp1-Tag mice. Taken together, these data validate the use of hSDSCs for targeting human brain tumors. They may represent therapeutically effective cells for the treatment of intracranial tumors after autologous transplantation
Formation of laser plasma channels in a stationary gas
The formation of plasma channels with nonuniformity of about +- 3.5% has been
demonstrated. The channels had a density of 1.2x10^19 cm-3 with a radius of 15
um and with length >= 2.5 mm. The channels were formed by 0.3 J, 100 ps laser
pulses in a nonflowing gas, contained in a cylindrical chamber. The laser beam
passed through the chamber along its axis via pinholes in the chamber walls. A
plasma channel with an electron density on the order of 10^18 - 10^19 cm-3 was
formed in pure He, N2, Ar, and Xe. A uniform channel forms at proper time
delays and in optimal pressure ranges, which depend on the sort of gas. The
influence of the interaction of the laser beam with the gas leaking out of the
chamber through the pinholes was found insignificant. However, the formation of
an ablative plasma on the walls of the pinholes by the wings of the radial
profile of the laser beam plays an important role in the plasma channel
formation and its uniformity. A low current glow discharge initiated in the
chamber slightly improves the uniformity of the plasma channel, while a high
current arc discharge leads to the formation of overdense plasma near the front
pinhole and further refraction of the laser beam. The obtained results show the
feasibility of creating uniform plasma channels in non-flowing gas targets.Comment: 15 pages, 7 figures, submitted to Physics of Plasma
Complete repair of dystrophic skeletal muscle by mesoangioblasts with enhanced migration ability.
Efficient delivery of cells to target tissues is a major problem in cell therapy. We report that enhancing delivery of mesoangioblasts leads to a complete reconstitution of downstream skeletal muscles in a mouse model of severe muscular dystrophy (alpha-sarcoglycan ko). Mesoangioblasts, vessel-associated stem cells, were exposed to several cytokines, among which stromal- derived factor (SDF) 1 or tumor necrosis factor (TNF) alpha were the most potent in enhancing transmigration in vitro and migration into dystrophic muscle in vivo. Transient expression of alpha4 integrins or L-selectin also increased several fold migration both in vitro and in vivo. Therefore, combined pretreatment with SDF-1 or TNF-alpha and expression of alpha4 integrin leads to massive colonization (>50%) followed by reconstitution of >80% of alpha-sarcoglycan-expressing fibers, with a fivefold increase in efficiency in comparison with control cells. This study defines the requirements for efficient engraftment of mesoangioblasts and offers a new potent tool to optimize future cell therapy protocols for muscular dystrophies
Correlation of circulating CD133+ progenitor subclasses with a mild phenotype in Duchenne muscular dystrophy patients.
Various prognostic serum and cellular markers have been identified for many diseases, such as cardiovascular diseases and tumor pathologies. Here we assessed whether the levels of certain stem cells may predict the progression of Duchenne muscular dystrophy (DMD)
Marker-assisted introgression of the salinity tolerance locus Saltol in temperate japonica rice
Background Rice is one of the most salt sensitive crops at seedling, early vegetative and reproductive stages. Varieties
with salinity tolerance at seedling stage promote an efficient growth at early stages in salt affected soils, leading
to healthy vegetative growth that protects crop yield. Saltol major QTL confers capacity to young rice plants growing
under salt condition by maintaining a low Na+/
K+ molar ratio in the shoots.
Results Marker-assisted backcross (MABC) procedure was adopted to transfer Saltol locus conferring salt tolerance
at seedling stage from donor indica IR64-Saltol to two temperate japonica varieties, Vialone Nano and Onice. Forward
and background selections were accomplished using polymorphic KASP markers and a final evaluation of genetic
background recovery of the selected lines was conducted using 15,580 SNP markers obtained from Genotyping by
Sequencing. Three MABC generations followed by two selfing, allowed the identification of introgression lines achieving
a recovery of the recurrent parent (RP) genome up to 100% (based on KASP markers) or 98.97% (based on GBS).
Lines with highest RP genome recovery (RPGR) were evaluated for agronomical-phenological traits in field under nonsalinized
conditions. VN1, VN4, O1 lines were selected considering the agronomic evaluations and the RPGR% results
as the most interesting for commercial exploitation. A physiological characterization was conducted by evaluating
salt tolerance under hydroponic conditions. The selected lines showed lower standard evaluation system (SES) scores:
62% of VN4, and 57% of O1 plants reaching SES 3 or SES 5 respectively, while only 40% of Vialone Nano and 25% of
Onice plants recorded scores from 3 to 5, respectively. VN1, VN4 and O1 showed a reduced electrolyte leakage values,
and limited negative effects on relative water content and shoot/root fresh weight ratio.
Conclusion The Saltol locus was successfully transferred to two elite varieties by MABC in a time frame of three years.
The application of background selection until BC3F3
allowed the selection of lines with a RPGR up to 98.97%. Physiological
evaluations for the selected lines indicate an improved salinity tolerance at seedling stage. The results supported
the effectiveness of the Saltol locus in temperate japonica and of the MABC procedure for recovering of the RP
favorable traits
Os custos da aterosclerose em Portugal
Copyright © 2020 Sociedade Portuguesa de Cardiologia. Published by Elsevier España, S.L.U. All rights reserved.© 2020 Sociedade Portuguesa de Cardiologia. Published by Elsevier Espa ̃na, S.L.U. This is an open access article under the CC-BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Introduction and objectives: Cardiovascular disease is the leading cause of death in Portugal and atherosclerosis is the most common underlying pathophysiological process. The aim of this study was to quantify the economic impact of atherosclerosis in Portugal by estimating disease-related costs.
Methods: Costs were estimated based on a prevalence approach and following a societal perspective. Three national epidemiological sources were used to estimate the prevalence of the main clinical manifestations of atherosclerosis. The annual costs of atherosclerosis included both direct costs (resource consumption) and indirect costs (impact on population productivity). These costs were estimated for 2016, based on data from the Hospital Morbidity Database, the health care database (SIARS) of the Regional Health Administration of Lisbon and Tagus Valley including real-world data from primary care, the 2014 National Health Interview Survey, and expert opinion.
Results: The total cost of atherosclerosis in 2016 reached 1.9 billion euros (58% and 42% of which was direct and indirect costs, respectively). Most of the direct costs were associated with primary care (55%), followed by hospital outpatient care (27%) and hospitalizations (18%). Indirect costs were mainly driven by early exit from the labor force (91%).
Conclusions: Atherosclerosis has a major economic impact, being responsible for health expenditure equivalent to 1% of Portuguese gross domestic product and 11% of current health expenditure in 2016.info:eu-repo/semantics/publishedVersio
VCAM-1 expression on dystrophic muscle vessels has a critical role in the recruitment of human blood-derived CD133+ stem cells after intra-arterial transplantation.
Recently our group demonstrated the myogenic capacity of human CD133(+) cells isolated from peripheral blood when delivered in vivo through the arterial circulation into the muscle of dystrophic scid/mdx mice. CD133(+) stem cells express the adhesion molecules CD44, LFA-1, PSGL-1, alpha4-integrins, L-selectin, and chemokine receptor CCR7. Moreover these cells adhere in vitro to VCAM-1 spontaneously and after stimulation with CCL19. Importantly, after muscle exercise, we found that the expression of VCAM-1 is strongly up-regulated in dystrophic muscle vessels, whereas the number of rolling and firmly adhered CD133(+) stem cells significantly increased. Moreover, human dystrophin expression was significantly increased when muscle exercise was performed 24 hours before the intra-arterial injection of human CD133(+) cells. Finally, treatment of exercised dystrophic mice with anti-VCAM-1 antibodies led to a dramatic blockade of CD133(+) stem cell migration into the dystrophic muscle. Our results show for the first time that the expression of VCAM-1 on dystrophic muscle vessels induced by exercise controls muscle homing of human CD133(+) stem cells, opening new perspectives for a potential therapy of muscular dystrophy based on the intra-arterial delivery of CD133(+) stem cells
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