Influence of feeding on the circadian rhythm of digestive enzymes in cultivated juveniles of the freshwater crayfish Cherax quadricarinatus (Parastacidae)

Se analiza en juveniles en etapa de engorde (7 g) de Cherax quadricarinatus, el ritmo circadiano de los niveles de proteínas totales, la actividad de las proteasas, lipasas y amilasas, y su posible modificación en función del momento de alimentación matutino (8 h) y vespertino (17 h). En general, la actividad de las enzimas digestivas de los juveniles de C. quadricarinatus no mostró un patrón circadiano de secreción, a excepción de las lipasas, donde se observó un incremento de actividad hacia la tarde-noche y disminución hacia las primeras horas de la mañana. Los niveles de proteína total, la actividad de proteinasas y amilasas registradas en la glándula digestiva, permanecieron prácticamente inalterados en todos los experimentos. A pesar de ello, se observó tendencia a que los niveles de actividad de proteinasas disminuyan luego del pulso de alimentación, recuperando los niveles anteriores 3 h después, independientemente del horario de alimentación. En cambio la actividad de amilasa no mostró ninguna tendencia por efecto del horario de alimentación. El estudio de los patrones de secreción de las enzimas digestivas y sus posibles modificaciones, podría ser utilizado como una herramienta para establecer los momentos del día más propicios para la alimentación de los juveniles en cultivo.ABSTRACT. We analyze in juvenile Cherax quadricarinatus fattening stage, the circadian rhythm of total protein levels, activity of proteases, lipases and amylases, and their possible change as a function of morning (8 h) and evening (17 h) feeding. In general, the activity of digestive enzymes of juvenile C. quadricarinatus showed no circadian pattern of secretion of lipases except where there was an increase towards the evening-night and a decrease towards the early hours of the morning. The total protein levels, the activity of proteinases and amylases of juveniles of C. quadricarinatus registered in the midgut gland remained virtually unchanged in all experiments. However, a non-significant tendency to diminish the proteinase activity levels after the feeding pulse was observed, with a return to previous enzymatic levels after 3 h. In contrast, the amylase activity did not show an observable effect by the feeding schedule. The study of the patterns of the digestive enzyme secretion and their possible changes, could be used as a tool to establish the most favorable times of the day for juveniles feeding.Fil: Sacristán, Hernán Javier. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Biodiversidad y Biologia Experimental; Argentina; Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biologia Experimental y Aplicada; Argentina;Fil: Franco-Tadic, Luis M.. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Biodiversidad y Biologia Experimental. Laboratorio de Fisiologia de Crustáceos; Argentina;Fil: Lopez, Laura Susana. Universidad de Buenos Aires. Facultad de Cs.exactas y Naturales. Departamento de Biodiversidad y Biologia Experimental; Argentina; Consejo Nacional de Invest.cientif.y Tecnicas. Oficina de Coordinacion Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biologia Experimental y Aplicada; Argentina

Development and characterization of bioactive alginate microcapsules with cedarwood essential oil

In this work, sodium alginate microcapsules containing cedarwood essential oil (CWO) for uses in anti-acne tonic were prepared by ionic gelification of alginate with calcium chloride (CaCl2) and subsequent addition of glutaraldehyde to improve the crosslinking degree. Alginate microcapsules with cedarwood essential oil were obtained in an encapsulator with a 600 μm nozzle using different alginate concentrations (1, 3 and 4% w/v) , and different compositions of the coagulation solution with CaCl2 concentrations of 0.1, 0.25 and 0.5 M, and addition of glutaraldehyde at two concentrations: 12.5% and 50% (0.1 g L−1 and 10 g L−1, respectively). The effect of alginate concentration was followed by viscosimetry and the influence of the CaCl2 concentration and presence of glutaraldehyde on the microcapsules' shape as well as the total content on encapsulated cedarwood essential oil were evaluated by means of stereoscopic magnifying glass, scanning electron microscopy (SEM) and UV vis spectrophotometry. Results show that proper shape formation is obtained for an alginate concentration of 3% w/v. With regard to the total encapsulated cedarwood oil, as the CaCl2 concentration in the gelifying-coagulating solution increases the efficiency of the encapsulated oil. Best results in terms of micro-bead shape and total amount of encapsulated oil were obtained for a CaCl2 concentration of 0.5 M without glutaraldehyde with a maximum encapsulation of 177.2 mg per gram of microcapsule.Ferrandiz, M.; Lopez, A.; Franco, E.; Garcia-Garcia, D.; Fenollar, D.; Balart, R. (2017). Development and characterization of bioactive alginate microcapsules with cedarwood essential oil. Flavour and Fragrance Journal. 32(3):184-190. doi:10.1002/ffj.3373S18419032

Seasonal and Spatial Patterns in Salinity, Nutrients, and Chlorophyll α in the Alvarado Lagoonal System, Veracruz, Mexico

Ten monthly collections, distributed among three seasons, were taken from July 2000 to June 2001 in the Alvarado lagoonal system, Veracruz, Mexico. Variables measured in situ included dissolved oxygen, salinity, and water temperature. Water samples were collected to determine concentrations of ammonium, nitrates, nitrites, orthophosphates, total phosphorus and chlorophyll α. Collections representing the rainy season were taken in September and October, those for the nortes season were taken in November, December, and January, and dry season collections were taken during February, March, May June, and July. There was seasonal and spatial variation in nutrient concentrations, and they were related to the discharge of the rivers; concentrations increased during the rainy and nortes seasons. Other factors affecting water quality included the constant discharge of organic materials into the system, resuspension of sediments during the nortes season and the biological activity within the system that assimilated the nutrients in the water. The Alvarado lagoonal system has three separate zones based on physicochemical characteristics; Camaronera Lagoon, Buen Pais Lagoon and the urban zone of Alvarado Lagoon, and the river zone in Alvarado Lagoon

Selective oxidation of aromatic alcohols in the presence of C3N4 photocatalysts derived from the polycondensation of melamine, cyanuric and barbituric acids

A set of C3N4 samples has been prepared by using melamine, cyanuric acid and barbituric acid as the precursors. The materials were subjected both to physical and chemical characterization and were used as photocatalysts for the selective oxidation of aromatic alcohols in water suspension under UV and visible irradiation. The photoactivity of the materials versus the partial oxidation of four substituted benzyl alcohols was investigated. The type and position of the substituents in the aromatic molecule influenced conversion and selectivity to the corresponding aldehyde. The presence of barbituric and cyanuric acids in the preparation method has changed the graphitic-C3N4 structure, and therefore both the characteristics of the material and the ability of light to activate the surface of the photocatalyst. The most active material prepared in the presence of melamine and cyanuric acid showed a remarkable selectivity towards the aldehyde even under visible irradiation

Effects of Osteopathic Visceral Treatment in Patients with Gastroesophageal Reflux: A Randomized Controlled Trial

Osteopathic manual treatment has been recommended as a non-pharmacological therapy for Gastroesophageal Reflux Disease (GERD). However, to date, no study has supported the effectiveness of this intervention with respect to the symptoms of the disease. Our goal was to assess the effect of an osteopathic manual technique for the lower esophageal sphincter on GERD symptoms, cervical mobility and on the C4 spinous process pressure pain threshold (PPTs). Methods: A randomized, double-blind placebo-controlled trial was performed. Sixty subjects suffering from GERD participated in this study and were randomly assigned to either an experimental group (EG) (n = 29), who received the osteopathic technique for the lower esophageal sphincter, or to a control group (CG) (n = 31), who received a manual contact, which mimicked the osteopathic technique without exerting any therapeutic force. Randomization was computer-generated, with allocation concealed by sequentially numbered, opaque, sealed envelopes. The GerdQ questionnaire was used to assess symptom changes the week after intervention. Cervical Range of Motion (CROM) and algometer were used to evaluate cervical mobility and PPTs before and after both treatments. Before–after between groups comparison (t-test) was used for statistical analysis of the outcome, with two measurement points (GerdQ), while repeated-measures ANOVA was used for those outcomes with four measurement points (CROM and PPT). Results: The application of the osteopathic manual treatment in subjects with GERD produced a significant improvement in symptoms one week after the intervention (p = 0.005) with a between-groups difference of 1.49 points in GerdQ score (95% CI: 0.47–2.49). PPT C4 improved in the EG after the treatment (p = 0.034; η 2 = 0.048) (between-groups difference 8.78 Newton/cm2 ; 95% CI: 0.48–17.09). CROM also increased in the EG compared to the CG (p < 0.001; η 2 = 0.108) (between-groups difference 33.89 degrees; 95% CI: 15.17–52.61). Conclusions: The manual osteopathic technique produces an improvement in GERD symptoms one week after treatment, cervical mobility, and PPTs. This may mean that osteopathic treatment is useful for improving symptoms of GER

The April 16 2016 Mw7.8 Muisne Earthquake in Ecuador – Preliminary Observations from the EEFIT Reconnaissance Mission of May 24 - June 7

On April 16 2016 an Mw7.8 earthquake with epicentre 29km south-southeast of Muisne in northern Manabí caused around 700 fatalities, injured 30,000 and destroyed several sections of the towns of Pedernales, Portoviejo, Canoa, Bahía de Caráquez and Manta, most of them important centres of tourism on the coast of Ecuador. During May 24-June 7 a team was deployed by the Earthquake Engineering Field Investigation Team (EEFIT) with the objective of surveying the damage and recording observations that would help the scientific and professional community understand the event and its consequences. The team, all co-authors of this paper, investigated structural damage patterns, surveyed 1,332 buildings, validated landslide data obtained from satellite imagery for 30 sites, and interviewed 120 families at 3 shelters. The damage observed in low- and mid-rise buildings seems to correlate well with the spectral response measured in Manta, Portoviejo, and Pedernales. Satellite-based landslide identification proved effective in an 80-90% of the cases investigated. The immediate unemployment spike, based on our limited survey, seemed to reach about 50% in the affected population