Insectos de preocupación forestal en la provincia de Buenos Aires

La “avispa taladradora” Tremex fuscicornis y los “escarabajos de ambrosia” (aún no está determinado el género presente en Argentina pero se cree que se trata de Xyleborus spp) están afectando las plantaciones de latifoliadas de toda la provincia de Buenos Aires causando pérdidas económicas en las forestaciones atacadas. Tremex es una avispa que produce galerías en una gran cantidad de árboles de hoja ancha (Populus, Salix, Quercus, Ulmus, entre otros). Generalmente ataca arboles estresados a los cuales les causa la muerte. El Xyleborus se trata de escarabajos que cultivan un hongo dentro del árbol que luego les servirá de alimento y, contrario a Tremex, este grupo de insectos atacan arboles que a simple vista parecerían ser vigorosos.Facultad de Ciencias Agrarias y Forestale

Insectos de preocupación forestal en la provincia de Buenos Aires

La “avispa taladradora” Tremex fuscicornis y los “escarabajos de ambrosia” (aún no está determinado el género presente en Argentina pero se cree que se trata de Xyleborus spp) están afectando las plantaciones de latifoliadas de toda la provincia de Buenos Aires causando pérdidas económicas en las forestaciones atacadas. Tremex es una avispa que produce galerías en una gran cantidad de árboles de hoja ancha (Populus, Salix, Quercus, Ulmus, entre otros). Generalmente ataca arboles estresados a los cuales les causa la muerte. El Xyleborus se trata de escarabajos que cultivan un hongo dentro del árbol que luego les servirá de alimento y, contrario a Tremex, este grupo de insectos atacan arboles que a simple vista parecerían ser vigorosos.Facultad de Ciencias Agrarias y Forestale

¿Cómo forestar en la provincia de Buenos Aires?

La actividad forestal es una de las que más diversifica los establecimientos agrícolas - ganaderos de la provincia de Buenos Aires. La misma puede estar dirigida a un beneficio netamente económico, montes comerciales, o en busca del bienestar animal y de diversos cultivos. Además se deben considerar los beneficios ecológicos que otorga una forestación: mejora las propiedades del suelo en el cual se encuentra, permite la captación de Dióxido de Carbono (CO2), aumenta la retención de agua, entre muchas otrasFacultad de Ciencias Agrarias y Forestale

The threat of the ambrosia beetle Megaplatypus mutatus (Chapuis) (=Platypus mutatus Chapuis) to world poplar resources

We describe the life cycle of Megaplatypus mutatus (Chapuis) (=Platypus mutatus) and the damage it causes to poplar resources in Argentina. This insect, native to the subtropical and tropical areas of South America, has extended its range into temperate regions, reaching as far south as Neuquén in Argentinean Patagonia. The damage is caused by the adult insects, which bore large gallery systems into living poplars (Populus spp.), willows (Salix spp.) and many other broadleaf species, including important fruit trees species such as apples (Malus spp.), walnuts (Juglans spp.) and avocados (Persea spp.). The galleries degrade the lumber and weaken the tree stems, which often then break during windstorms. A recent introduction of M. mutatus to Italy demonstrates that this insect can be transported long distances between countries, and therefore presents a threat worldwide - particularly to poplar cultivation. We review the taxonomic nomenclature for this pest, provide a summary of the life cycle, hosts and damage and summarize actions taken to reduce the risk of introduction of M. mutatus to Canada.Facultad de Ciencias Agrarias y Forestale

Methodological constraints in interpreting serum paraoxonase-1 activity measurements: an example from a study in HIV-infected patients

<p>Abstract</p> <p>Background</p> <p>Paraoxonase-1 (PON1) is an antioxidant enzyme that attenuates the production of the monocyte chemoattractant protein-1 (MCP-1) <it>in vitro</it>. Although oxidation and inflammation are closely related processes, the association between PON1 and MCP-1 has not been completely characterised due, probably, to that the current use of synthetic substrates for PON1 measurement limits the interpretation of the data. In the present study, we explored the relationships between the circulating levels of PON1 and MCP-1 in human immunodeficiency virus-infected patients in relation to the multifunctional capabilities of PON1.</p> <p>Methods</p> <p>We measured selected variables in 227 patients and in a control group of 409 participants. Serum PON1 esterase and lactonase activities were measured as the rates of hydrolysis of paraoxon and of 5-(thiobutyl)-butyrolactone, respectively. Oxidised LDL and MCP-1 concentrations were determined by enzyme-linked immunosorbent assay. High-density lipoproteins cholesterol, apolipoprotein A-I, and C-reactive protein concentrations were measured by standard automated methods.</p> <p>Results</p> <p>There were significant relationships between PON1 activity and several indices of oxidation and inflammation in control subjects and in infected patients. However, these relationships varied not only with disease status but also on the type of substrate used for PON1 measurement.</p> <p>Conclusion</p> <p>The present study is a cautionary tale highlighting that results of clinical studies on PON1 may vary depending on the methods used as well as the disease studied. Until more specific methods using physiologically-akin substrates are developed for PON1 measurement, we suggest the simultaneous employment of at least two different substrates in order to improve the reliability of the results obtained.</p

Treatment of hypertriglyceridemia and HIV: fenofibrate-induced changes in the expression of chemokine genes in circulating leukocytes

Fenofibrate changed the expression of chemokine genes in circulating leukocytes of HIV-infected patients with hypertriglyceridemia. The data suggest that fenofibrate when effective in the treatment of lipoprotein abnormalities, may act as a modulator of systemic inflammation. This particular action, therefore, may also influence the clinical course of the disease

PPARs in Regulation of Paraoxonases: Control of Oxidative Stress and Inflammation Pathways

The paraoxonase (PON) group of enzymes, composed of PON1, PON2, and PON3, play an important role in decreasing oxidative stress by degrading lipid peroxides. PON1 synthesis is upregulated by PPAR. Several pharmacological compounds (acting as antioxidants and, hence, atheroprotective) stimulate both PPAR activity and PON1 expression. Recent evidence suggests that PON1 and the monocyte chemoattractant protein-1 (MCP-1) are involved in coordinating the inflammatory response in damaged tissues; PPAR may be central in the regulation of these biochemical pathways. This article reviews the state of knowledge on PON1 biochemistry and function, the influence of genetic variation, and the regulation of PON1 expression by pharmaceutical compounds that increase PPAR activity. We also describe recent lines of evidence suggesting links between PON1 and MCP-1 and how their production may be regulated by PPAR

Air Biofiltration Applied to Odours Treatment

Producción CientíficaDevelopment of biological techniques for air pollution control has been triggered by the implementation of new health and safety guidelines, which are nowadays including odorous contaminants. These techniques have shown several advantages when compared with physicochemical processes; such as the lower energy requirements, capital and operating costs, and easy maintenance and control. Biofiltration is now a well-known and extensively applied technology, with more than 7500 full-scale biofilters operating in Europe

The threat of the ambrosia beetle Megaplatypus mutatus (Chapuis) (=Platypus mutatus Chapuis) to world poplar resources

We describe the life cycle of Megaplatypus mutatus (Chapuis) (=Platypus mutatus) and the damage it causes to poplar resources in Argentina. This insect, native to the subtropical and tropical areas of South America, has extended its range into temperate regions, reaching as far south as Neuquén in Argentinean Patagonia. The damage is caused by the adult insects, which bore large gallery systems into living poplars (Populus spp.), willows (Salix spp.) and many other broadleaf species, including important fruit trees species such as apples (Malus spp.), walnuts (Juglans spp.) and avocados (Persea spp.). The galleries degrade the lumber and weaken the tree stems, which often then break during windstorms. A recent introduction of M. mutatus to Italy demonstrates that this insect can be transported long distances between countries, and therefore presents a threat worldwide - particularly to poplar cultivation. We review the taxonomic nomenclature for this pest, provide a summary of the life cycle, hosts and damage and summarize actions taken to reduce the risk of introduction of M. mutatus to Canada.Facultad de Ciencias Agrarias y Forestale

Decreased paraoxonase-1 activity is associated with alterations of high-density lipoprotein particles in chronic liver impairment

<p>Abstract</p> <p>Background</p> <p>Paraoxonase-1 (PON1), a lactonase synthesized by the liver, circulates in blood bound to high-density lipoproteins (HDL). This enzyme is thought to degrade oxidized phospholipids and play an important role in the organism's antioxidant and anti-inflammatory system. Chronic liver diseases are characterized by decreased serum PON1 activity. The aim of the present study was to investigate the compositional changes in HDL that could influence PON1 activity in liver impairment.</p> <p>Methods</p> <p>The study was performed in samples from five patients with advanced liver cirrhosis and with preserved renal function, chosen on the basis of having low serum PON1 activity and high serum PON1 concentration. As a control group, we accessed five healthy volunteers from among our hospital staff. Lipid and protein compositional analysis of lipoprotein particles were done by high-performance liquid chromatography, gel electrophoresis, and Western-Blot.</p> <p>Results</p> <p>HDL particles from cirrhotic patients had an increased phospholipid content that was inversely correlated to PON1 activity. The HDL particles contained high levels of PON1 that corresponded, in part, to an immunoreactive protein of high molecular weight (55 kDa) not present in control subjects. This protein was identified as glycosylated PON1 and was also present in biopsies from patients with steatosis and from rats with CCl₄-induced hepatic impairment. These changes were associated with an increased plasma concentration of markers of oxidative stress, inflammation and fibrogenesis.</p> <p>Conclusion</p> <p>Abnormalities in the composition of lipids and proteins of HDL particles, including PON1 glycosylation, are associated with the decrease in serum PON1 activity in patients with liver disease. These alterations may adversely affect the protective role of HDL against oxidative stress and inflammation in these patients.</p