The origin of 15R-prostaglandins in the Caribbean coral Plexaura homomalla: Molecular cloning and expression of a novel cyclooxygenase

The highest concentrations of prostaglandins in nature are found in the Caribbean gorgonian Plexaura homomalla. Depending on its geographical location, this coral contains prostaglandins with typical mammalian stereochemistry (15S-hydroxy) or the unusual 15R-prostaglandins. Their metabolic origin has remained the subject of mechanistic speculations for three decades. Here, we report the structure of a type of cyclooxygenase (COX) that catalyzes transformation of arachidonic acid into 15R-prostaglandins. Using a homology-based reverse transcriptase–PCR strategy, we cloned a cDNA corresponding to a COX protein from the R variety of P. homomalla. The deduced peptide sequence shows 80% identity with the 15S-specific coral COX from the Arctic soft coral Gersemia fruticosa and ≈50% identity to mammalian COX-1 and COX-2. The predicted tertiary structure shows high homology with mammalian COX isozymes having all of the characteristic structural units and the amino acid residues important in catalysis. Some structural differences are apparent around the peroxidase active site, in the membrane-binding domain, and in the pattern of glycosylation. When expressed in Sf9 cells, the P. homomalla enzyme forms a 15R-prostaglandin endoperoxide together with 11R-hydroxyeicosatetraenoic acid and 15R-hydroxyeicosatetraenoic acid as by-products. The endoperoxide gives rise to 15R-prostaglandins and 12R-hydroxyheptadecatrienoic acid, identified by comparison to authentic standards. Evaluation of the structural differences of this 15R-COX isozyme should provide new insights into the substrate binding and stereospecificity of the dioxygenation reaction of arachidonic acid in the cyclooxygenase active site.

Health reforms in Latin America: processes and results

Two types of health reforms in Latin America are analysed: one based on insurance and service commodification and the one referred to the unified public systems of progressive governments. Health insurance with explicit service packages has not fulfilled their purposes of universal coverage, equal access to necessary health services and improvement of health conditions but has opened health as a field of profit making for insurance companies and private health providers. The national health services as a state obligation have developed territorialized health services and widened substantially timely access to the majority of the population. The adoption of an integrated and wide social policy has an impact on population well fare. It faces some problems derived from the old health systems and the power of the insurance and medical complex.

INJURIES RELATED TO COMPETITIVE AND NONCOMPETITIVE SPORTS IN ELDERLY MEN

Objective: To verify the sociodemographic profile and the frequency of musculoskeletal injuries in elderly people who practice competitive and noncompetitive sports activities in the city of Pelotas, RS. Methods: Descriptive study, including 29 male subjects, aged 65 years or older, who practiced sports modalities in a competitive and noncompetitive way, in the city of Pelotas, in 2015. Data collection was performed through the application of a questionnaire with questions addressing economic, sociodemographic, nutritional and behavioral issues, and injuries sustained in sports activities. Statistical analysis was performed by calculating measures of central tendency for continuous variables and proportions for categorical variables. Results: The current practice of competitive sports was described by 58.6% (n=17) of the subjects, and the most practiced sports were 7-a-side football (53.0%, n=9), tennis (23.5%, n=4) and swimming (23.5%, n=4). Noncompetitive sports were practiced by 44.8% (n=13), and tennis was the most popular sport played (92.3%, n=12). The frequency of injuries among individuals practicing competitive and noncompetitive sports was, respectively, 35.3% (n=6), and 38.5% (n=5). The most frequent injuries were epicondylitis (50.0%, n=3) and meniscus injuries (60.0%, n=3), and the most affected body regions were knee (27.3%, n=3), elbow (27.3%, n=3), and shoulder (18.2%, n=2). The injuries occurred during the sports activities, and the dominant side was the one affected in 63.6% (n=7). Conclusion: This study verified that the occurrence of injuries in elderly individuals who practice sports is relevant, even among those who practice them noncompetitively, with epicondylitis as the most frequent among them, whereas meniscus injuries are the most frequent among those who practice competitive sports.

Chemical composition of Boletus pinophilus and Clitocybe subconnexa: preservation with gamma irradiation

The short shelf life of mushrooms is a barrier for their distribution and, therefore, there has been extensive research to find technologies that ensure the preservation of mushrooms, maintaining their organoleptic and nutritional properties (1]. Irradiation has proved its technological feasibility to be safely used in the reduction of food losses, being recognized by international organizations as a valid conservation alternative in extending shelflife of many foods. The aim of the present work was to validate the use of 2 kGy dose of gamma radiation to maintain chemical composition of wild mushrooms. Boletus pinophilus Pihit & Dermek and Clitocybe subconnexa Murrill wild samples were obtained in Tnis-os-Montes; subsequently, the samples were divided in two groups: control (non-irradiated, 0 kGy) and irradiated (2 kGy). The irradiation of the samples was performed in a 6°Co experimental chamber. Moisture, protein, fat, carbohydrates and ash were determined following the standard procedures [2]. Free sugars and tocopherols were determined by high performance liquid chromatography coupled to a refraction index detector (HPLC-RI) and a fluorescence detector, respectively; fatty acids were determined by gas-liquid chromatography with flame ionization detection (GC-FID) [3]. The protein and ash content was preserved in both groups, although the sugars and tocopherols decreased in the irradiated samples. Sugars and fatty acids showed significant changes after irradiation treatment, particularly in B. pinophillus, nevertheless, the magnitude of the obtained differences did not seem to be sufficient to affect the chemical profiles of the assayed mushrooms. Overall, the detected chemical changes might be considered as allowable, in view of the high advantages offered by gamma irradiation at decontamination and/or disinfestation level.

Effects of electron-beam irradiation on chemical and antioxidation parameters of wild Macrolepiota procera dried samples

Mushrooms are very perishable foods due to their high susceptibility to moisture loss, changes in color and texture, or microbiological spoilage. Drying is considered as the most appropriate method to prevent these alterations, but it has some limitations, such as shrinkage, enzymatic and non-enzymatic browning reactions, and oxidation of lipids and vitamins. Irradiation might effectively attenuate the undesirable changes caused by drying process, ensuring also higher shelf-life of mushrooms and their decontamination [I]. In the present work, the combined effects of electron-beam irradiation (at 0, 0.5, 1 and 6 kGy doses) and storage time (at 0, 6 and 12 months) were evaluated and compared. Macrolepiota procera (Scop.) Singer wild samples were obtained in Tnis-os-Montes, in the Northeast of Portugal, and dried at 30 •c in an oven. Subsequently, the samples were divided in four groups: control (non-irradiated, 0 kGy); sample 1 (0.5 kGy); sample 2 (1 kGy) and sample 3 (6 kGy). The irradiation was performed at the lNCTInstitute of Nuclear Chemistry and Technology (lNCT), in Warsaw, Poland. Moisture, protein, fat, carbohydrates and ash were determined following standard procedures. Free sugars and tocopherols were determined by high performance liquid chromatography coupled to a refraction index detector (HPLC-RI) and a fluorescence detector, respectively; fatty acids were determined by gas-liquid chromatography with flame ionization detection (GC-FID). Antioxidant activity was evaluated in the methanolic extracts by in vitro assays measuring DPPH (1,1-diphenyl-2- picrylhydrazyl) radical scavenging activity, reducing power, inhibition of ~-carotene bleaching and inhibition oflipid peroxidation using thiobarbituric acid reactive substances (TBARS) assay. Total phenolics were also determined by the Folin-Ciocalteu assay. All the parameters showed a decrease tendency with storage time. Trehalose and y-tocopherol were preserved with 1 kGy dose. Electron-beam irradiation did not impart additional changes to most of the chemical and antioxidant parameters of M. procera dried samples. This is a very promising result, since electron-beam irradiation might attenuate most unwanted changes caused by drying, maintaining its long-term effectiveness.

Estética e Desporto

Apesar de o desporto ter desempenhado desde sempre um papel importante na minha vida, quer como modesto jogador de ténis, quer como apaixonado adepto sobretudo de futebol e de rugby, a verdade é que apenas fiz dele assunto de estudo e de reflexão mais sistemática, quando comecei a leccionar na Universidade de Évora diversas disciplinas da área epistemológica da filosofia aos cursos de Educação Física e Desporto. Depressa se tornou claro para mim que a área da filosofia do desporto é um enorme campo de possibilidades de investigação que tenho procurado desenvolver desde então. Nesse quadro, a estética fenomenológica de Merleau-Ponty e de Dufrenne desempenham um papel decisivo na abordagem que procuro efectuar no presente volume. Por outro lado, desde que comecei a estudar e a ensinar filosofia do desporto, a obra de Sílvio Lima revelou-se um interlocutor privilegiado para esta componente da minha actividade académica, como se pode observar nos dois últimos capítulos de "Estética e Desporto".