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1.
J Environ Manage ; 210: 239-254, 2018 Mar 15.
Article in English | MEDLINE | ID: mdl-29348059

ABSTRACT

Reducing fertilizer use is a priority in the quest for sustainable forestry systems. In short rotation Eucalyptus plantations, NPK pellets are routinely added to the seedling's top soil layer at planting, potentially leading to increased seedling mortality, nutrient loss and environmental degradation. To address this triple challenge, the development of efficient fertilization practices is essential. In the present work, we synthesized a crosslinked acrylic-cellulosic superabsorbent composite (SAPH-BAL) containing small amounts of specific nutrients integrated in the polymer matrix. We analyzed the composite's chemical and rheological properties, and assessed the viability of Eucalyptus plantations supplied with it at planting. Physiological measurements confirmed the suitability of SAPH-BAL in greenhouse-grown potted seedlings subjected to different growth conditions, showing that it efficiently delivers nutrients while protecting seedlings from drought stress. Field experiments carried out at ten South American locations covering an ample range of environmental conditions confirmed the beneficial effect of SAPH-BAL on growth and survival in comparison to the conventional fertilization scheme (superabsorbent + 75 g NPK). Furthermore, it was found that plants treated with SAPH-BAL were less affected by the differences in rainfall regimes during the experiments compared to those fertilized conventionally. To the best of our knowledge this is the first report describing the successful use of superabsorbents for root targeted delivery of fertilizers in forestry operations.


Subject(s)
Fertilizers , Forestry , Conservation of Natural Resources , Eucalyptus , Soil , Water
2.
Bioresour Technol ; 162: 259-65, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24759641

ABSTRACT

A treatment train combining a biological and a physical approach was investigated for the first time in order to remediate polycyclic aromatic hydrocarbons (PAHs)-polluted effluents. Given the hydrophobic nature of these contaminants, the presence of non-ionic surfactants is compulsory to allow their bioavailability. The presence of these surfactants also entails an advantage in order to ease contaminant removal by the formation of aqueous two-phase systems (ATPS). The segregation ability of environmentally benign salts such as potassium tartrate, citrate, and oxalate was discussed for extracting phenanthrene (PHE), pyrene (PYR), and benzo[a]anthracene (BaA). The biological remediation efficiency reached circa 60% for PHE and PYR, and more than 80% for BaA. The coupling of ATPS subsequent stage by using potassium citrate allowed increasing the total PAH remediation yields higher than 97% of PAH removal. The viability of the proposed solution was investigated at industrial scale by using the software tool SuperPro Designer.


Subject(s)
Polycyclic Aromatic Hydrocarbons/isolation & purification , Surface-Active Agents/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Computer Simulation , Ions , Rheology , Salts/chemistry , Solubility
3.
Bioresour Technol ; 146: 689-695, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23985354

ABSTRACT

In this work, a novel remediation strategy consisting of a sequential biological and physical process is proposed to remove dyes from a textile polluted effluent. The decolorization ability of Anoxybacillus flavithermus in an aqueous effluent containing two representative textile finishing dyes (Reactive Black 5 and Acid Black 48, as di-azo and antraquinone class, respectively) was proved. The decolorization efficiency for a mixture of both dyes reached almost 60% in less than 12h, which points out the suitability of the selected microorganism. In a sequential stage, an aqueous biphasic system consisting of non-ionic surfactants and a potassium-based organic salt, acting as the salting out agent, was investigated. The phase segregation potential of the selected salts was evaluated in the light of different thermodynamic models, and remediation levels higher than 99% were reached.


Subject(s)
Biodegradation, Environmental , Coloring Agents/analysis , Industrial Waste/analysis , Textile Industry , Waste Disposal, Fluid/methods , Anoxybacillus/metabolism , Anthraquinones/analysis , Biomass , Coloring Agents/chemistry , Culture Media , Equipment Design , Filtration , Models, Theoretical , Naphthalenesulfonates/analysis , Polysorbates/chemistry , Potassium Citrate/chemistry , Surface-Active Agents/chemistry , Textiles , Time Factors , Water Purification/methods
4.
Mediators Inflamm ; 2013: 967067, 2013.
Article in English | MEDLINE | ID: mdl-23533314

ABSTRACT

Interleukin-(IL-) 12 has been recently suggested to participate during development of insulin resistance in obese mice. Nevertheless, serum IL-12 levels have not been accurately determined in overweight and obese humans. We thus studied serum concentrations of IL-12 in Mexican adult individuals, examining their relationship with low-grade inflammation and obesity-related parameters. A total of 147 healthy individuals, 43 normal weight, 61 overweight, and 43 obese subjects participated in the study. Circulating levels of IL-12, tumor necrosis factor-alpha (TNF- α ), leptin, insulin, glucose, total cholesterol, and triglyceride were measured after overnight fasting in all of the study subjects. Waist circumference and body fat percentage were recorded for all the participants. Serum IL-12 was significantly higher in overweight and obese individuals than in normal weight controls. Besides being strongly related with body mass index (r = 0.5154), serum IL-12 exhibited a significant relationship with abdominal obesity (r = 0.4481), body fat percentage (r = 0.5625), serum glucose (r = 0.3158), triglyceride (r = 0.3714), and TNF- α (r = 0.4717). Thus, serum levels of IL-12 are increased in overweight and obese individuals and show a strong relationship with markers of low-grade inflammation and obesity in the Mexican adult population. Further research is needed to understand the role of IL-12 in developing obesity-associated alterations in humans.


Subject(s)
Inflammation/blood , Interleukin-12/blood , Obesity/blood , Adult , Female , Humans , Insulin/blood , Leptin/blood , Male , Triglycerides/blood , Tumor Necrosis Factor-alpha/blood , Young Adult
6.
Arthroscopy ; 17(7): 768-71, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11536099

ABSTRACT

We present the case of a 16-year-old boy with an 18-month history of pain in the left groin for 18 months. In addition to the simple radiographic examination, magnetic resonance imaging, bone scan, and computed tomography were necessary to finally diagnose an acetabulum osteoid osteoma (AOO). Excision of the lesion was performed arthroscopically and pathologic testing confirmed the diagnosis. The patient's symptoms disappeared immediately after the surgery, and had not reappeared as of the 6-month postoperative evaluation. We conclude that arthroscopic excision of an AOO is possible and avoids the aggressive open approach as well as operative hip dislocation.


Subject(s)
Acetabulum , Arthroscopy , Bone Neoplasms/surgery , Osteoma, Osteoid/surgery , Adolescent , Humans , Male
7.
Curr Allergy Asthma Rep ; 1(4): 337-41, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11892056

ABSTRACT

This article reviews the current information surrounding the efficacy of barrier creams as a protective measure against contact dermatitis. The principles of the proposed effects of barrier creams on the skin and the experimental and clinical data regarding their efficacy in the prevention of irritant and allergic contact dermatitis are discussed.


Subject(s)
Dermatitis, Contact/prevention & control , Dermatologic Agents/therapeutic use , Ointments/therapeutic use , Protective Agents/therapeutic use , Animals , Dermatitis, Occupational/prevention & control , Humans
9.
Comp Biochem Physiol B ; 103(3): 517-21, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1458827

ABSTRACT

1. Calmodulin (CaM) was detected during secretion of electron-dense granules by Entamoeba histolytica trophozoites with immunofluorescence. 2. It was purified to apparent homogeneity by chromatography with a yield of 2.26 micrograms of calmodulin/mg of protozoan protein. Purity was established by gel electrophoresis. 3. The parasite calmodulin has properties characteristic of calmodulin isolated from other eukaryotes: an apparent molecular weight of 19 or 17 kDa in presence of EGTA or CaCl2, respectively, activation in a calcium dependent manner of bovine heart cyclic nucleotide phosphodiesterase, and its UV spectrum.


Subject(s)
Calmodulin/metabolism , Entamoeba histolytica/metabolism , Animals , Calmodulin/isolation & purification , Cytoplasmic Granules/metabolism , Entamoeba histolytica/ultrastructure , Microscopy, Fluorescence , Molecular Weight , Subcellular Fractions/metabolism
10.
Arch Invest Med (Mex) ; 22(3-4): 259-68, 1991.
Article in English | MEDLINE | ID: mdl-1844110

ABSTRACT

The acidified fetal bovine serum (FBS) produces a factor which inhibits the adipose differentiation of murine fibroblasts 3T3-F442A. In this work, we studied if the inhibitory factor (IF) has any effect on the proliferation of 3T3-F442A cells. Our data showed an increment in the number of cells cultured in the presence of IF. We do not know how the IF maintains the cell proliferation. Furthermore, we investigated if IF acts on the resting state (Go) of the 3T3-F442A. We found that the IF prevented the adipose differentiation in the state (Go), this data suggests that the 3T3-F442A in this state (Go) were not yet compromised to difference to adipocytes. We also showed that bovine serum (BS) had an inhibitory activity too, but this was lower than FBS. This report suggests that the IF may play a role during the development of the adipose tissue.


Subject(s)
3T3 Cells/cytology , Biological Factors/physiology , Blood Physiological Phenomena , Animals , Biological Factors/blood , Biological Factors/isolation & purification , Cattle/blood , Cattle/embryology , Cell Differentiation , Chromatography, Gel , Chromatography, Ion Exchange , Culture Media , Depression, Chemical , Fetal Blood/physiology , Hydrogen-Ion Concentration , Interphase , Mice
11.
Arch Invest Med (Mex) ; 22(2): 235-44, 1991.
Article in English | MEDLINE | ID: mdl-1726451

ABSTRACT

3T3 are murine cells of an established heteroploid cellular line. Some clones of this cellular line, when cultured under adequate conditions differentiate into adipocytes. During the process of differentiation, the cells undergo a change from the elongated fibroblastic shape to a round or oval form and accumulate small drops of lipids within their cytoplasma. These lipid drops fuse into one large drop which displaces the nucleus towards the periphery, giving the cell the aspect of a mature adipocyte of white adipose tissue. The cells not only change their morphology, but they also present important biochemical changes. They show a simultaneous increase in triglyceride synthesis and activity of lipogenic enzymes. There is also an increase in the response of the activity of various hormones and the de novo synthesis of the receptors to such hormones, as insulin and ACTH. During the process of differentiation important changes occur in the synthesis of various proteins, such as actin, tubulin, and other proteins which also make up the cellular cytoskeleton, forming part of the lipid transportation within the adipose cell. The adipocytic differentiation of 3T3 cells depends on adipogenic serum factors used in the supplementary culture medium. These adipogenic factors seem to play an important role in the development of adipose tissue. There are hormones, chemical agents and serum factors which modulate adipocytic differentiation. The clone must be susceptible to adipocytic differentiation, it must reach a quiescent state and find itself in adipogenic conditions for the 3T3 cells to differentiate into adipocytes. It must also carry out an DNA synthesis which is an expression of the new phenotype. The differentiation of 3T3 cells in terminal. The fact that these cells present an adipocytic conversion under physiologic conditions and with adipogenic hormones which exist in the whole animal has been demonstrated. All of these characteristics show that the 3T3 cells may be used as an adequate experimental system to analyze the events which occur during the differentiation and development of adipose tissue.


Subject(s)
3T3 Cells/cytology , Adipose Tissue/cytology , 1-Methyl-3-isobutylxanthine/pharmacology , 3T3 Cells/drug effects , 3T3 Cells/metabolism , Adipose Tissue/metabolism , Adrenergic beta-Agonists/pharmacology , Animals , Cats/blood , Cattle/blood , Cell Cycle/drug effects , Cell Differentiation/drug effects , Cells, Cultured , Culture Media/pharmacology , Cyclic AMP/analogs & derivatives , Cyclic AMP/pharmacology , Cytoskeletal Proteins/biosynthesis , DNA Replication , Dinoprost/pharmacology , Enzymes/biosynthesis , Gene Expression , Hormones/pharmacology , Lipids/biosynthesis , Mice , Receptors, Cell Surface/biosynthesis
12.
Arch Invest Med (Mex) ; 21 Suppl 1: 273-6, 1990.
Article in Spanish | MEDLINE | ID: mdl-2136497

ABSTRACT

The presence of IgA anti-Entamoeba histolytica antibodies has been demonstrates in intestinal secretions and serum of human amebiasis. We investigated which are the cellular components of trophozoites that react with IgA anti-ameba antibodies from immune serum, colostrum and human milk. The cellular localization of such antigens was accomplished by an indirect immunoperoxidase technique using anti-human IgA (alpha chain specific) labeled with peroxidase, both for light and transmission electron microscopy. Intracellular antigens were localized after permeating the parasites with cold acetone (-10 degrees C) for 3 min. and cryosections of 1 micron thick. The antigens that react with IgA antibodies from immune serum, colostrum and human milk were located in the plasma membrane and the internal portion of some cytoplasmic vesicles. So far, it is unknown what is the biological function of IgA in human amebiasis but in other systems it protects against certain parasites.


Subject(s)
Antibodies, Protozoan/immunology , Antigens, Protozoan/analysis , Entamoeba histolytica/immunology , Immunoglobulin A/immunology , Animals , Antibodies, Protozoan/isolation & purification , Colostrum/immunology , Entamoeba histolytica/ultrastructure , Entamoebiasis/blood , Entamoebiasis/immunology , Humans , Immunoenzyme Techniques , Immunoglobulin A/isolation & purification , Microscopy, Immunoelectron , Milk, Human/immunology , Subcellular Fractions/immunology
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