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The conversion of bioethanol to ethylene in gas phase and atmospheric pressure was investigated over γ-Al2O3 supported copper and nickel catalysts. These catalysts were prepared by co-precipitation and pre-treated with hydrogen at 450 °C. Six catalysts were studied at 450 °C under a nitrogen atmosphere. It was found that the monometallic Cu/γ-Al2O3 catalyst exhibited the highest ethylene concentration, with a selectivity of around 90 %. The bioethanol conversion obtained was between 57 %-86 %. Another catalyst that exhibited high concentration values was the NiCu1 : 7 bimetallic catalyst. The catalysts were characterised using XRD, SEM, EDS, TEM, TGA, FTIR, Raman, and N2-physisoption techniques. Furthermore, the Cu/γ-Al2O3 catalyst was studied under different reduction temperatures and gas flow conditions. It was found that the catalysts reduced at 350 °C and 35 ml/min N2 flow presented ethylene concentrations between (0.18-0.21) g/L. Moreover, the catalyst deactivation was identified to be first order and the equation of the Cu/γ-Al2O3 catalyst deactivation model was determined. Carbonaceous deposits over the used sample were not detected by Raman and FTIR. It was determined that the Cu/γ-Al2O3 catalyst deactivation could be mainly attributed to the blocking of the catalytic sites by strongly adsorbed compounds and hydroxylation of the catalyst surface.

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This review presents an updated scenario of findings and evolutions of encapsulation of bioactive compounds for food and agricultural applications. Many polymers have been reported as encapsulated agents, such as sodium alginate, gum Arabic, chitosan, cellulose and carboxymethylcellulose, pectin, Shellac, xanthan gum, zein, pullulan, maltodextrin, whey protein, galactomannan, modified starch, polycaprolactone, and sodium caseinate. The main encapsulation methods investigated in the study include both physical and chemical ones, such as freeze-drying, spray-drying, extrusion, coacervation, complexation, and supercritical anti-solvent drying. Consequently, in the food area, bioactive peptides, vitamins, essential oils, caffeine, plant extracts, fatty acids, flavonoids, carotenoids, and terpenes are the main compounds encapsulated. In the agricultural area, essential oils, lipids, phytotoxins, medicines, vaccines, hemoglobin, and microbial metabolites are the main compounds encapsulated. Most scientific investigations have one or more objectives, such as to improve the stability of formulated systems, increase the release time, retain and protect active properties, reduce lipid oxidation, maintain organoleptic properties, and present bioactivities even in extreme thermal, radiation, and pH conditions. Considering the increasing worldwide interest for biomolecules in modern and sustainable agriculture, encapsulation can be efficient for the formulation of biofungicides, biopesticides, bioherbicides, and biofertilizers. With this review, it is inferred that the current scenario indicates evolutions in the production methods by increasing the scales and the techno-economic feasibilities. The Technology Readiness Level (TRL) for most of the encapsulation methods is going beyond TRL 6, in which the knowledge gathered allows for having a functional prototype or a representative model of the encapsulation technologies presented in this review.

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Background: This work studied the use of the organic fertilizers DTPA-Fe and EDDS-Fe as iron chelates for solar driven photo-Fenton process at natural pH. This process was proposed to investigate its performance on removing a mixture of agrochemicals (propiconazole, imidacloprid and diuron) from pineapple processing wastewater to obtain a suitable effluent to be reused in the agricultural sector. Methods: Experiments were carried out in a solar simulator with a stirred cylindric photoreactor, with a volume of 150 mL and controlled temperature (20°C). The first set of experiments was carried out with ultrapure water to determine optimal iron and H 2O 2 concentrations. The second was performed with simulated wastewater of pineapple processing. Results: The optimized operational conditions for both iron complexes were 10 mg L -1 of Fe (III) and 25 mg L -1 of H 2O 2, since more than 80% of micropollutants (MP) (at an initial concentration of 1 mg L -1 of each compound) were removed in only 20 min with both DTPA-Fe and EDDS-Fe. The effect of organic matter and inorganic salts on radicals scavenging and chelates stability was also investigated in the experiments performed with synthetic pineapple processing wastewater. The results disclosed differences depending on the iron complex. Nitrites were the principal component influencing the tests carried out with EDDS-Fe. While carbonates at low concentration only significantly affected the experiments performed with DTPA-Fe, they were the major influence on the MPs removal efficiency decrease. In contrast, the presence of Ca 2+ and Mg 2+ only influence on this last one. Finally, the results of phytotoxicity disclosed the suitability of treated effluent to be reused in the agricultural sector.  Conclusions: This work demonstrated that solar powered photo-Fenton catalysed by iron fertilizer EDDS is a suitable technology for depolluting water streams coming from pineapple processing plants at circumneutral pH, and its subsequent reuse for crop irrigation.

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Understanding the link between seamounts and large pelagic species (LPS) may provide important insights for the conservation of these species in open water ecosystems. The seamounts along the Cocos Ridge in the Eastern Tropical Pacific (ETP) ocean are thought to be ecologically important aggregation sites for LPS when moving between Cocos Island (Costa Rica) and Galapagos Islands (Ecuador). However, to date, research efforts to quantify the abundance and distribution patterns of LPS beyond the borders of these two oceanic Marine Protected Areas (MPAs) have been limited. This study used drifting-pelagic baited remote underwater video stations (BRUVS) to investigate the distribution and relative abundance of LPS at Cocos Ridge seamounts. Our drifting-pelagic BRUVS recorded a total of 21 species including elasmobranchs, small and large teleosts, dolphins and one sea turtle; of which four species are currently threatened. Depth of seamount summit was the most significant driver for LPS richness and abundance which were significantly higher at shallow seamounts (< 400 m) compared to deeper ones (> 400m). Distance to nearest MPA was also a significant predictor for LPS abundance, which increased at increasing distances from the nearest MPA. Our results suggest that the Cocos Ridge seamounts, specifically Paramount and West Cocos which had the highest LPS richness and abundance, are important aggregation sites for LPS in the ETP. However, further research is still needed to demonstrate a positive association between LPS and Cocos Ridge seamounts. Our findings showed that drifting pelagic BRUVS are an effective tool to survey LPS in fully pelagic ecosystems of the ETP. This study represents the first step towards the standardization of this technique throughout the region.

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RESUMEN La ontogenia humana está basada en fundamentos genéticos y epigenéticos. Con el objetivo de estructurar los referentes teóricos sobre el papel relevante de la epigenética en la ontogenianormal y defectuosa que contribuyan a la promoción de salud y prevención de enfermedad, se realizó la revisión de 37 referencias bibliográficas. La epigenética es el conjunto de procesos químicos dependientes del ambiente que modifican la expresión del ácido desoxirribonucleico, sin alterar su secuencia. Su acción está presente durante toda la vida, especialmente en la prenatal cuando, por modificaciones ambientales intraútero ocurre la programación epigenética que hace al humano susceptible a defectos en la ontogenia, incluso a padecer ulteriormente de enfermedades crónicas no transmisibles. Se han reportado factores ambientales inductores de marcas epigenéticas, entre ellos: alimentación, hábitos tóxicos, estrés, consumo inadecuado de ácido fólico y técnicas de reproducción asistida, todos modificables; su conocimiento constituye un baluarte inestimable en la promoción de salud y prevención de enfermedad (AU).

ABSTRACT Human ontogeny is based in genetic and epigenetic fundaments. 37 bibliographic references were reviewed with the objective of structuring the theoretical referents on the relevant role of epigenetics in normal and defective ontogeny to contribute to health promotion and disease prevention. Epigenetics is the whole of chemical processes depending from the environment that modify the deoxyribonucleic acid expression without modifying its sequence. Its action is present during all lifetime, especially at pre-natal times; when due to intrauterine environmental modifications the epigenetic programming takes place, making humans susceptible to defects in ontogeny, even to subsequently suffer non-communicable chronic diseases. Environmental factors inducing epigenetic marks have been reported: food, toxic habits, stress, folic acid inadequate intake and assisted reproduction techniques, all modifiable. Its knowledge is an invaluable bulkward in health promotion and disease prevention (AU).

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RESUMEN La ontogenia humana está basada en fundamentos genéticos y epigenéticos. Con el objetivo de estructurar los referentes teóricos sobre el papel relevante de la epigenética en la ontogenianormal y defectuosa que contribuyan a la promoción de salud y prevención de enfermedad, se realizó la revisión de 37 referencias bibliográficas. La epigenética es el conjunto de procesos químicos dependientes del ambiente que modifican la expresión del ácido desoxirribonucleico, sin alterar su secuencia. Su acción está presente durante toda la vida, especialmente en la prenatal cuando, por modificaciones ambientales intraútero ocurre la programación epigenética que hace al humano susceptible a defectos en la ontogenia, incluso a padecer ulteriormente de enfermedades crónicas no transmisibles. Se han reportado factores ambientales inductores de marcas epigenéticas, entre ellos: alimentación, hábitos tóxicos, estrés, consumo inadecuado de ácido fólico y técnicas de reproducción asistida, todos modificables; su conocimiento constituye un baluarte inestimable en la promoción de salud y prevención de enfermedad.

ABSTRACT Human ontogeny is based in genetic and epigenetic fundaments. 37 bibliographic references were reviewed with the objective of structuring the theoretical referents on the relevant role of epigenetics in normal and defective ontogeny to contribute to health promotion and disease prevention. Epigenetics is the whole of chemical processes depending from the environment that modify the deoxyribonucleic acid expression without modifying its sequence. Its action is present during all lifetime, especially at pre-natal times; when due to intrauterine environmental modifications the epigenetic programming takes place, making humans susceptible to defects in ontogeny, even to subsequently suffer non-communicable chronic diseases. Environmental factors inducing epigenetic marks have been reported: food, toxic habits, stress, folic acid inadequate intake and assisted reproduction techniques, all modifiable. Its knowledge is an invaluable bulkward in health promotion and disease prevention.

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OBJECTIVE: To describe the clinical and hormonal characteristics of patients with Sheehan syndrome. METHODS: We performed a 20-year cohort study (1969 to 1989) of patients with Sheehan syndrome who were cared for in the endocrinology unit of the México Hospital in San José, Costa Rica. Medical history, physical examination findings, and laboratory test results were documented and reviewed. RESULTS: Sixty patients with a diagnosis of Sheehan syndrome were identified. Mean age at diagnosis was 45.8 ± 10.6 years. The average time between the previous obstetric event and Sheehan syndrome diagnosis was 13 years. Thirteen patients (22%) had a home birth. The median parity was 7. The most frequent obstetric antecedents were history of obstetric hemorrhage in 49 (82%), shock in 28 (47%), blood transfusion in 26 (43%), and peripartum hysterectomy in 4 (7%). The most common symptoms included asthenia and adynamia in 51 (85%), amenorrhea in 44 (73%), loss of axillary or pubic hair in 40 (67%), and agalactia in 40 (67%). The most common findings on physical examination were absence of axillary hair in 56 (93%) and pubic hair in 56 (93%), dry skin in 49 (82%), and pallor in 42 (70%). When a combined pituitary test was performed, 38 of 38 patients (100%) had human growth hormone deficiency, 29 of 30 patients (97%) had adrenal insufficiency, 8 of 10 patients (80%) had hypothyroidism, 8 of 12 patients (67%) had hypogonadism, and 9 of 13 patients (69%) had prolactin deficiency. Despite early onset of symptoms, Sheehan syndrome was diagnosed relatively late in these 60 patients. Hemorrhage during the last delivery, especially if severe and/or associated with shock or transfusion, was the most important obstetric antecedent event. Absence of amenorrhea or presence of postpartum lactation did not exclude the diagnosis. Abnormal responses of human growth hormone to insulin tolerance testing and of prolactin to thyrotropin-releasing hormone confirm the diagnosis. CONCLUSIONS: Identification of patients affected with Sheehan syndrome is critical to avoid delays in diagnosis and treatment. Appropriate replacement therapy is capable of yielding complete remission of symptoms.

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El termino trombofilia se refiere a una predisposición a fenómenos troboembólicos y es causada por factores hereditarios y adquiridos. Nuestro entendimiento sobre la trombofilia hereditaria ha mejorado tremendamente en los últimos años. Con el descubrimiento de la resistencia a proteína C activada y la mutación en el gen de la protombrina, actualmente, se puede determinar una anormalidad hereditaria en muchos pacientes con trombosis venosa profunda. Los trastornos genéticos deben ser mejor considerados como factores de riesgo de TVP más que causas propiamente dichas, y se deben tener en cuenta que actúan en comunión con otros factores genéticos y circunstanciales.

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El término neumonía recurrente es un problema clínico importante que se define como la presencia de al menos dos episodios de infección pulmonar aguda durante el lapso de un año; o la presencia de tres o más sin límite de tiempo. Dicha patología se observa más frecuentemente en la población pediátrica y en pacientes inmunosuprimidos. La recurrencia de un proceso infeccioso a nivel pulmonar indudablemente nos debe orientar a hacia la búsqueda de una patología de fondo que facilite la ocurrencia del mismo. Presentamos el caso de una paciente de 21 años que presentó 3 cuadros bronconeumónicos con la misma localización radiológica en un lapso de 4 años documentándose finalmente la presencia de bronquiectasias como causa busyacente.

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La púrpura de Henoch-Schõnlein es una vasculitis de pequeños vasos que se presenta de predominio en niños. Es una enfermedad multisistémica que afecta principalmente la piel, el sistema articular, gastrointestinal y renal; requiriendo éste la mayor atención. Su etiopatogenia es aun desconocida, sin embargo presenta un fuerte componente inmunológico. Presentamos aquí el caso de un paciente de 18 años, quién previo buen estado general presenta rash petequial en miembros inferiores asociado a artralgias migratorias y edemas importantes, quién posteriormente inicia con dolor abodminal y vómitos volviéndose estos sus síntomas principales. En este artículo hacemos una revisión de las principales manifestaciones clínicas, diagnósticos diferenciales y hallazgos histopatológicos de esta enfermedad

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Analiza retrospectivamente a 100 pacientes ASA 1-2 (ASA-Clasificación del riesgo anestésico según la Sociedad Americana de Anestesiología), sometidas a operación Cesárea bajo anestesia conductiva en la Clínica Latacunga, localizada en la ciudad del mismo nombre, en el período de 1994 a 1996. De las 100 pacientes seleccionadas, 50 fueron intervenidas quirúrgicamente con anestesia peridural y 50 con anestesia raquídean. Se analizan una serie de variables como: paridad, causas de cesárea, complicaciones anestésicas, medicamentos complementarios de anestesia y APGAR del recién nacido. No hubo diferencia significativamente entre los dos tipos de anestesia, solamente la hipotensión producida por la Anestesia Raquídea fue ligeramente mayor que la producida por la Anestesia Peridural, además, la anestesia raquídea requirió de menos anestésicos y anelgésicos complementarios...

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