TFP Bioeconomy Impact post Covid-19 on the agricultural economy.

BACKGROUND: This research was focused on measuring the TFP bioeconomy post-Covid-19 in six regions of the world. METHODS: The panel data was organized with FAO Statistics data. Linear programming with an enveloping data analysis (DEA) approach was used to measure the Malmquist TFP indices to determine the inter-annual productivity and technical efficiency changes by region. RESULTS: The results show that the effect of Covid-19 on the bioeconomy productivity during the period 2012-2021 on average decreased by 11.6%. This effect was explained by the decomposition of the productivity change into the changes in technical efficiency. The workers decreased their efficiency by 11.7%. In the Northern American region, it decreased by 21.6%, in the Southern European region by 10.1, and in Western Europe by 11.7%. CONCLUSION: The results show a downward trend that was affected in the year 2019 by Covid-19, however, it was possible to recover in the following year. One of the conclusions of these results is the effect of the immediate strategies that the governments of the region implemented. This effect was a little slower in the North American, Southeastern, and Eastern European regions. Finally, it is concluded that the measures implemented by the governments in the studied regions had an increasing effect in conditions of variable scale returns. In other words, the companies that remained on a constant scale decreased.

The effect of synthesis conditions and process parameters on aerogel properties.

Aerogels are remarkable nanoporous materials with unique properties such as low density, high porosity, high specific surface area, and interconnected pore networks. In addition, their ability to be synthesized from various precursors such as inorganics, organics, or hybrid, and the tunability of their properties make them very attractive for many applications such as adsorption, thermal insulation, catalysts, tissue engineering, and drug delivery. The physical and chemical properties and pore structure of aerogels are crucial in determining their application areas. Moreover, it is possible to tailor the aerogel properties to meet the specific requirements of each application. This review presents a comprehensive review of synthesis conditions and process parameters in tailoring aerogel properties. The effective parameters from the dissolution of the precursor step to the supercritical drying step, including the carbonization process for carbon aerogels, are investigated from the studies reported in the literature.

Addition of ß-glucans in diets for tropical gar (Atractosteus tropicus) larvae: effects on growth, digestive enzymes and gene expression of intestinal epithelial integrity and immune system.

The effect of ß-glucans 1,3/1,6 from Saccharomyces cerevisiae yeast at different inclusion percentages (0.0, 0.2, 0.4, 0.6, and 0.8%) in the diet for tropical gar (Atractosteus tropicus) larvae was evaluated on growth, digestive enzyme activity and, relative expression of the immune system genes. The bioassay started on the third day after hatching (DAH) and lasted 21 days, using a total of 1500 larvae of 0.055 ± 0.008 g and, a total length of 2.46 ± 0.26 cm. Larviculture was carried out in a recirculation system with 15 tanks of 70 L using a density of 100 organisms per experimental unit. No significant differences in larval growth were observed by the inclusion of ß-glucans (p > 0.05). Digestive enzymes showed changes in lipase and trypsin activities, presenting higher values in fish fed 0.6% and 0.8% ß-glucans diets compared to the other treatments (p < 0.05). Leucine-aminopeptidase, chymotrypsin, acid phosphatase, and alkaline phosphatase activity showed higher activities in larvae fed with a 0.4% ß-glucan diet compared to the control group. The relative expression of intestinal membrane integrity (mucin 2) muc-2, (occludins) occ, (nucleotide-binding oligomerization domain) nod-2, and immune system lys (lysosome) genes showed over-expression in larvae fed the 0.4% ß-glucan diet to the rest of the treatments (p < 0.05). The inclusion of ß-glucans at 0.4-0.6% in diets for A. tropicus larvae could improve larviculture, as effects on the increase in the activity of several digestive enzymes and the expression of genes of the immune system.

Hybrid Methacrylated Gelatin and Hyaluronic Acid Hydrogel Scaffolds. Preparation and Systematic Characterization for Prospective Tissue Engineering Applications.

Hyaluronic acid (HA) and gelatin (Gel) are major components of the extracellular matrix of different tissues, and thus are largely appealing for the construction of hybrid hydrogels to combine the favorable characteristics of each biopolymer, such as the gel adhesiveness of Gel and the better mechanical strength of HA, respectively. However, despite previous studies conducted so far, the relationship between composition and scaffold structure and physico-chemical properties has not been completely and systematically established. In this work, pure and hybrid hydrogels of methacroyl-modified HA (HAMA) and Gel (GelMA) were prepared by UV photopolymerization and an extensive characterization was done to elucidate such correlations. Methacrylation degrees of ca. 40% and 11% for GelMA and HAMA, respectively, were obtained, which allows to improve the hydrogels' mechanical properties. Hybrid GelMA/HAMA hydrogels were stiffer, with elastic modulus up to ca. 30 kPa, and porous (up to 91%) compared with pure GelMA ones at similar GelMA concentrations thanks to the interaction between HAMA and GelMA chains in the polymeric matrix. The progressive presence of HAMA gave rise to scaffolds with more disorganized, stiffer, and less porous structures owing to the net increase of mass in the hydrogel compositions. HAMA also made hybrid hydrogels more swellable and resistant to collagenase biodegradation. Hence, the suitable choice of polymeric composition allows to regulate the hydrogels´ physical properties to look for the most optimal characteristics required for the intended tissue engineering application.

[Outpatient treatment of acute injuries of upper extremities with axillary plexus anesthesia in the emergency department-Is that possible without continuous anesthesia attendance?] / Ambulante Versorgung akuter Verletzungen der oberen Extremität in der Notfallambulanz in axillärer Plexusanästhesie ­ Ist das ohne durchgehende Anästhesiebegleitung machbar?

BACKGROUND: The incorporation into the routine operating procedure of patients with small but acute hand and forearm injuries requiring surgery who present in the emergency admission department, represents a challenge due to limited resources. The prompt treatment in the emergency admission department represents an alternative. This article retrospectively reports the authors' experiences with a treatment algorithm in which emergency patients were treated by ultrasound-guided axillary brachial plexus blocks (ABPB) and surgery carried out in the emergency department without further anesthesia attendance. METHODS: Patients were preselected by the surgeon if they were suitable for a standardized treatment without anesthesia attendance during surgery. If there were no anesthesiological or surgical contraindications patients received an ABPB in the holding area of the operating room (OR) under standard monitoring. Blocks were performed as a multi-injection, ultrasound-guided technique which is anatomically described in detail. Patients >60 kg received a total volume of 30 ml of a mixture of 10 ml 1% ropivacaine (100 mg) and 20 ml 2% prilocaine (400 mg). Patients <60 kg received the same mixture with a reduced volume of 25 ml corresponding to 82.5 mg ropivacaine and 332.5 mg prilocaine. After controlling for block success patients were admitted to the emergency department and the surgical procedure was carried out under supervision by the surgeon without further anesthesia attendance. At discharge patients were explicitly instructed that in the case of any complications or a continuation of the block for more than 24 h they should contact the emergency department. RESULTS: Between January 2013 and November 2017 a total of 566 patients (46.4 years, range 11-88 years, 174.9 cm, range 140-211cm, 80.8 kg, range 42-178kg, ASA 1/2/3, 190/338/38, respectively) were treated according to a standardized protocol. The ABPBs were performed by 74 anesthetists. In 5% of the patients the initial block was incomplete and rescue blocks were performed with a maximum of 2­3ml 1% prilocaine per corresponding nerve. After completion the block was ensured and all patients underwent surgery without further analgesics or local anesthetic infiltration by the surgeon. Complications related to the ABPB and readmissions were not observed. CONCLUSION: It could be demonstrated that minor surgery could be carried out safely and effectively with a defined algorithm using ABPB in selected patients outside the OR without permanent anesthesia attendance: however, indispensable prerequisites for such procedures are careful patient selection, patient compliance, the safe and effective performance of the ABPB and reliable agreement with the surgeon.

Protein and lipid requirements of three-spot cichlid Cichlasoma trimaculatum larvae.

Determination of the main nutritional requirements at different developmental stages is a prerequisite in the formulation of feeds for newly cultured fish species. In the present study, the lipid and protein requirements of larvae of a native Mexican fish, the three-spot cichlid Cichlasoma trimaculatum, were assessed using a two-factor experimental design that considered four protein (35, 40, 45, and 50%) and two lipid levels (16 and 22%) on growth, survival, and digestive enzyme activities. The best growth and feed efficiency results were obtained when larvae were fed diets including 45% protein and 22% lipids. Comprehensive evaluation of the profile of digestive enzymes using multivariate analysis also demonstrated significant differences in nutritional condition generated by varying inclusion of nutrients. Thus, an increase in protein led to an increase in alkaline protease activity and a reduction in leucine aminopeptidase activity, and the reduction of dietary lipid content led to a significant increase in lipase and trypsin enzymatic activities. Based on our results, C. trimaculatum larvae have a high capacity to hydrolyze both nutrients (protein and lipids) for the high digestive enzyme activities and increase their growth, particularly with a diet containing 45% protein and 22% lipids.

[Schwannoma of the inferior gluteal nerve as a rare cause of gluteal radiating chronic low back pain]. / Schwannom des Nervus gluteus inferior als seltene Ursache von nach gluteal einstrahlenden chronischen Rückenschmerzen.

This is the first report of a schwannoma of the inferior gluteal nerve (IGN) as a cause of chronic low back pain in a 43-year-old man. The patient suffered from severe pain radiating to the gluteal region. He was treated for months without pain relief and was on long-term disability. Only a targeted sonographic exam revealed a hypoechoic intrapelvic mass along the course of the IGN. By tumor resection, a schwannoma was histologically confirmed. After tumor removal the patient is free of pain with all medication discontinued. He has been fully reintegrated into his professional life.

Exposure to Radioactive Emanations of Medical Personnel in Percutaneous Nephrolithotomy.

The use of radioactive emanations has been of great importance for the performance of endourology procedures, such as percutaneous nephrolithotomy (NLP). The damage to health caused by radiation has been a sensitive issue. The objective of this work was to determine the dose received by the surgeon during NLP and the total dose generated by the fluoroscope. A cross-sectional study was conducted with data from a cohort study with a duration of 18 months that included 101 patients. Radiation was measured with dosimeter during the last 6 months. During the last 6 months of the study, 34 patients were submitted to surgery. The average age was 47 years. Average fluoroscopy time was 58.3 second (24-122 seconds) in both male and female groups, with 57.16 seconds and 58.95 seconds per case, respectively (P = .6). Radiation emitted during 6 months for the 34 patients was 330.5 mGy. The total radiation measured by the dosimeter was 1 mSv, which is equivalent to 0.3% of the total radiation applied during the procedures. Doses measured by the dosimeter on the surgeon were within the recommended annual doses although dose received by the hands exceeds the authorized limits (500 mSv/y).

Digestive proteases and in vitro protein digestibility of feed ingredients for the Central American river turtle, Dermatemys mawii.

Functional characteristics of digestive proteases and in vitro digestibility of several protein sources were studied in hatchlings of Central American river turtles, Dermatemys mawii. Acidic and alkaline proteases from the stomach and intestines were used, and optimums for acidic proteases were registered at 55°C and pH 2, while alkaline proteases were found at 55°C and pH 9. Ten protein ingredients, both vegetable and animal sources, were explored by the pH-STAT method, only for alkaline proteases. The degree of hydrolysis was at its highest for squid meal and lowest for blood meal, while the total free amino acids level was at its highest for squid meal, and lowest for wheat gluten meal. Our results indicate that D. mawii has a broad capacity to digest both animal and vegetable sources, and suggests some ingredients more suitable to design artificial diets for this species.

[Meniscal transplant: clinical and functional experience at one year follow-up]. / Trasplante de menisco: experiencia con seguimiento clínico y funcional a un año.

INTRODUCTION: In Mexico, the first meniscus transplant was performed in 2002. The objective was to describe the clinical evolution of patients with pain associated with postmenisectomy syndrome, who underwent meniscal allograft transplantation (MAT), with bony blocks via arthroscopy, with follow-up to one year. MATERIAL AND METHODS: A retrospective cohort study with a one-year follow-up was conducted. We included patients with joint interlining pain secondary to partial or total menisectomy, between 15 and 55 years of age, of both sexes, who underwent MAT. The clinical evolution was evaluated with visual analogue scale (VAS), SF-36 and Lysholm scale; the results are described in frequencies, percentages and p value was significant at 0.05. RESULTS: We included nine patients; eight men and one woman with an age of 31.3 years (16-52), the follow-up was 16.6 months (12-23). The preoperative VAS was 8.5 (6-10) and, at one year of follow-up, the average of this scale was 1.25 (0-5) (p 0.001). In the follow-up one year after the MAT, the Lysholm scale was on average 91 (68-100) and the SF-36 was on average 79.17 (65-92.92); three patients returned to their sports practice prior to the injury. CONCLUSION: This is the first report in Mexico that describes the one year follow-up of the MAT; significant clinical improvement was demonstrated (p 0.001) with remission of pain in the knee with previous menisectomy and in some cases the return to sports practice.

INTRODUCCIÓN: En México se realizó el primer trasplante de menisco en 2002. El objetivo fue describir la evolución clínica de pacientes con dolor asociado al síndrome postmeniscectomía que fueron sometidos a trasplante de menisco alogénico (MAT), con bloques óseos vía artroscópica con seguimiento a un año. MATERIAL Y MÉTODOS: Se realizó un estudio de cohorte retrospectiva con seguimiento a un año; se incluyeron pacientes con dolor en interlínea articular secundario a meniscectomía parcial o total, entre 15 y 55 años de edad, de ambos sexos, que fueron sometidos a MAT. La evolución clínica se evaluó con EVA, SF-36 y escala de Lysholm; los resultados se describen en frecuencias, porcentajes y valor de p significativa 0.05. RESULTADOS: Se incluyeron nueve pacientes; ocho hombres y una mujer con edad de 31.3 años (16-52), el seguimiento fue de 16.6 meses (12-23). La EVA prequirúrgica fue de 8.5 (6-10) y al año de seguimiento el promedio de esta escala fue de 1.25 (0-5) (p 0.001). En el seguimiento a un año posterior al MAT, la escala de Lysholm fue en promedio de 91 (68-100) y la SF-36 fue en promedio de 79.17 (65-92.92); tres pacientes regresaron a su práctica deportiva previa a la lesión. CONCLUSIÓN: Éste es el primer reporte en México del seguimiento a un año del MAT; se demostró mejoría clínica significativa (p 0.001) con remisión del dolor en la rodilla con meniscectomía previa y en algunos casos el retorno a la práctica deportiva.

Recommendations for the prevention and diagnosis of asthma in children: Evidence from international guidelines adapted for Mexico.

BACKGROUND: With the availability of high-quality asthma guidelines worldwide, one possible approach of developing a valid guideline, without re-working the evidence, already analysed by major guidelines, is the ADAPTE approach, as was used for the development of National Guidelines on asthma. METHODS: The guidelines development group (GDG) covered a broad range of experts from medical specialities, primary care physicians and methodologists. The core group of the GDG searched the literature for asthma guidelines 2005 onward, and analysed the 11 best guidelines with AGREE-II to select three mother guidelines. Key clinical questions were formulated covering each step of the asthma management. RESULTS: The selected mother guidelines are British Thoracic Society (BTS), GINA and GEMA 2015. Responses to the questions were formulated according to the evidence in the mother guidelines. Recommendations or suggestions were made for asthma treatment in Mexico by the core group, and adjusted during several rounds of a Delphi process, taking into account: 1. Evidence; 2. Safety; 3. Cost; 4. Patient preference - all these set against the background of the local reality. Here the detailed analysis of the evidence present in BTS/GINA/GEMA sections on prevention and diagnosis in paediatric asthma are presented for three age-groups: children with asthma ≤5 years, 6-11 years and ≥12 years. CONCLUSIONS: For the prevention and diagnosis sections, applying the AGREE-II method is useful to develop a scientifically-sustained document, adjusted to the local reality per country, as is the Mexican Guideline on Asthma.

Apósitos de polímeros naturales para regeneración de piel / Natural polymers aposites for skin regeneration

Resumen El presente artículo es una amplia revisión bibliográfica de algunos de los polímeros naturales más utilizados en la fabricación de apósitos para curación de heridas cutáneas y regeneración de piel en los últimos años. Asimismo, se presenta un análisis descriptivo de los polímeros de origen natural más estudiados en la ingeniería de tejidos, remarcando sus propiedades físicas, químicas y biológicas. Encontrando que las investigaciones más recientes se han centrado en la exploración de apósitos a partir de biopolímeros como una alternativa a los materiales sintéticos derivados del petróleo, debido a las propiedades que poseen, como una mayor biodegradabilidad, biocompatibilidad y sostenibilidad por ser obtenidos naturalmente. Sin embargo, aún no existe un apósito ideal que pueda ser aplicado de manera eficiente en todos los tipos de heridas; por lo que los investigadores se han enfocado en el desarrollo y la optimización de apósitos que satisfagan la mayoría de las necesidades para una etapa en particular de la herida.

Abstract This review includes the bio-polymers most used in recent years for the manufacturing of materials used as dressings in cutaneous wound healing and skin regeneration. Also, the natural polymers most studied in tissue engineering are mentioned, highlighting their physical, chemical and biological properties for skin regeneration and wound healing. Through an extensive review of the clinical and research uses different types of natural polymers were compared, as well as the results of chemical and biological tests carried out during experimental research performed internationally.

Non-ionizing radiofrequency electromagnetic waves traversing the head can be used to detect cerebrovascular autoregulation responses.

Monitoring changes in non-ionizing radiofrequency electromagnetic waves as they traverse the brain can detect the effects of stimuli employed in cerebrovascular autoregulation (CVA) tests on the brain, without contact and in real time. CVA is a physiological phenomenon of importance to health, used for diagnosis of a number of diseases of the brain with a vascular component. The technology described here is being developed for use in diagnosis of injuries and diseases of the brain in rural and economically underdeveloped parts of the world. A group of nine subjects participated in this pilot clinical evaluation of the technology. Substantial research remains to be done on correlating the measurements with physiology and anatomy.

Using cornstarch in microparticulate diets for larvicultured tropical gar (Atractosteus tropicus).

Aquaculture in Mexico has been developed by the cultivation of commercial species. In Tabasco, the cultivation of native species is mainly limited by the lack of nutrition studies to support its crop profitability. Among these species is the tropical gar (Atractosteus tropicus), which has great potential for cultivation. However, the nutritional value of carbohydrates in diets for this species which contribute to improved growth and survival, have not been evalulated,. Thus, in the present investigation, isoprotein and isolipid diets have been designed based on the substitution of cellulose by corn starch (D1: 0% starch-15% cellulose, D2: 7.5% starch-7.5% cellulose and D3: 15% starch-0% cellulose) and compared with a commercial trout diet (45% protein and 16% lipids). A total of 1800 larvae (0.008 ± 0.002 g and 10.5 ± LT 0.126 mm) were used, distributed in a recirculation system in order to evaluate growth and survival for 30 days. The results show higher growth and survival of 97% of larvae fed the D3 diet, while cannibalism in the species was mitigated. Major digestive enzyme activities occurred (acid protease, alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, carboxypeptidase A, lipase, α-glucosidase and amylase) for larvae fed D3. It is concluded that the contribution of corn starch (15%) replacing cellulose in the diet improves growth and survival of this species.

Unprocessed red meat and processed meat consumption and risk of stroke in the Spanish cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC).

BACKGROUND/OBJECTIVES: High intakes of unprocessed red or processed meat may increase the risk of stroke. We aimed to examine the association between unprocessed red meat, processed meat and total red meat consumption and risk of total stroke and ischaemic stroke. SUBJECTS/METHODS: Cox proportional hazards regression analyses were conducted based on the data for 41,020 men and women aged 29-69 years at baseline. RESULTS: During a mean follow-up of 13.8 years, 674 incident cases of stroke (531 ischaemic strokes, 79 haemorrhagic strokes, 42 subarachnoid haemorrhages and 22 mixed or unspecified events) were identified. After multiple adjustment, unprocessed red meat, processed meat and total red meat consumption were not correlated with incidence of total stroke or ischaemic stroke in either men or women. The hazard ratios (HRs) for unprocessed red meat and processed meat and risk of total stroke comparing the highest with the lowest quintiles were, respectively, 0.81 (95% confidence interval (CI) 0.54-1.21; P-trend=0.15) and 0.92 (95% CI 0.64-1.32; P-trend=0.82) in men and 1.21 (95% CI 0.79-1.85; P-trend=0.10) and 0.81 (95% CI 0.51-1.27; P-trend=0.17) in women. The HRs for unprocessed red meat and processed meat and risk of ischaemic stroke were, respectively, 0.80 (95% CI 0.51-1.25; P-trend=0.51) and 0.86 (95% CI 0.57-1.29; P-trend=0.77) in men and 1.24 (95% CI 0.74-2.05; P-trend=0.13) and 0.82 (95% CI 0.47-1.42; P-trend=0.31) in women. CONCLUSIONS: In the Spanish European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, unprocessed red meat and processed meat consumption were not associated with risk of stroke in men or women.

Development of digestive tract and enzyme activities during the early ontogeny of the tropical gar Atractosteus tropicus.

Changes in digestive enzyme activity and histology were studied in Atractosteus tropicus embryos, larvae and juvenile periods. Alkaline protease, chymotrypsin, carboxypeptidase A, lipase and α-amylase were detected in all periods and gradually increased until reaching the maximum peak in juveniles; meanwhile, acid protease was first detected at 5 days after hatching (dah) when first feeding started and trypsin and leucine aminopeptidase activities were detected from 19 dah, their values being increased gradually until reaching a maximum value at 31 dah. Acid and alkaline phosphatase activities increased from yolk-sac absorption (3 dah) until day 31 after hatching. Zymogram for acid protease showed two bands in active forms (0.4 and 0.5 Rfs) from day 5 after hatching and a third protease form (0.3 Rf) that appears at 31 dah. Two active forms (26.3 and 24.9 kDa) were detected using SDS-PAGE alkaline proteases zymogram at 5 dah, and an additional active form (44.1 kDa) was detected at 7 dah. Regarding the histological development of the digestive system, the exocrine pancreas containing zymogen granules was already visible at 3 dah, whereas at 5 dah first gastric glands were already detected in the stomach. Between 7 and 9 dah, the digestive tract of A. tropicus resembled that of a juvenile specimen with a well-developed and short oesophagus, stomach divided into a glandular and non-glandular (pyloric) stomach, folded intestine with pyloric caeca and a well-developed spiral valve (posterior intestine). Considering this, larvae of A. tropicus are capable of digesting several foods from yolk absorption (3 dah), maximizing its activities at 15 dah, age at which the organisms maximize its capability to absorb nutrients from diets provided.

Healthy lifestyle index and risk of gastric adenocarcinoma in the EPIC cohort study.

Several modifiable lifestyle factors, including smoking, alcohol, certain dietary factors and weight are independently associated with gastric cancer (GC); however, their combined impact on GC risk is unknown. We constructed a healthy lifestyle index to investigate the joint influence of these behaviors on GC risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. The analysis included 461,550 participants (662 first incident GC cases) with a mean follow-up of 11.4 years. A healthy lifestyle index was constructed, assigning 1 point for each healthy behavior related to smoking status, alcohol consumption and diet quality (represented by the Mediterranean diet) for assessing overall GC and also body mass index for cardia GC and 0 points otherwise. Risk of GC was calculated using Cox proportional hazards regression models while adjusting for relevant confounders. The highest versus lowest score in the healthy lifestyle index was associated with a significant lower risk of GC, by 51% overall (HR 0.49 95% CI 0.35, 0.70), by 77% for cardia GC (HR 0.23 95% CI 0.08, 0.68) and by 47% for noncardia GC (HR 0.53 (95% CI 0.32, 0.87), p-trends<0.001. Population attributable risk calculations showed that 18.8% of all GC and 62.4% of cardia GC cases could have been prevented if participants in this population had followed the healthy lifestyle behaviors of this index. Adopting several healthy lifestyle behaviors including not smoking, limiting alcohol consumption, eating a healthy diet and maintaining a normal weight is associated with a large decreased risk of GC.

Polysaccharide-based aerogel microspheres for oral drug delivery.

Polysaccharide-based aerogels in the form of microspheres were investigated as carriers of poorly water soluble drugs for oral administration. These bio-based carriers may combine the biocompatibility of polysaccharides and the enhanced drug loading capacity of dry aerogels. Aerogel microspheres from starch, pectin and alginate were loaded with ketoprofen (anti-inflammatory drug) and benzoic acid (used in the management of urea cycle disorders) via supercritical CO2-assisted adsorption. Amount of drug loaded depended on the aerogel matrix structure and composition and reached values up to 1.0×10(-3) and 1.7×10(-3) g/m(2) for ketoprofen and benzoic acid in starch microspheres. After impregnation, drugs were in the amorphous state in the aerogel microspheres. Release behavior was evaluated in different pH media (pH 1.2 and 6.8). Controlled drug release from pectin and alginate aerogel microspheres fitted Gallagher-Corrigan release model (R(2)>0.99 in both cases), with different relative contribution of erosion and diffusion mechanisms depending on the matrix composition. Release from starch aerogel microspheres was driven by dissolution, fitting the first-order kinetics due to the rigid starch aerogel structure, and showed different release rate constant (k1) depending on the drug (0.075 and 0.160 min(-1) for ketoprofen and benzoic acid, respectively). Overall, the results point out the possibilities of tuning drug loading and release by carefully choosing the polysaccharide used to prepare the aerogels.

Changes on digestive enzymes during initial ontogeny in the three-spot cichlid Cichlasoma trimaculatum.

A study was performed in order to understand the development of digestive enzymes during initial ontogeny of Cichlasoma trimaculatum, for which the activity of acidic and alkaline proteases, lipases, amylases and phosphatases was determined by means of biochemical and electrophoretic analysis. Our results showed that the activity of alkaline proteases, trypsin and chymotrypsin is present from day 6 after hatching (dah) during exogenous feeding with Artemia nauplii. The activities of carboxypeptidase A and leucine aminopeptidase are present from the first days, increasing at 6 dah and reaching their maximum activity at 9 dah while acid protease activity started at 9 dah. Furthermore, the lipase activity is detected on 6 dah and keeps increasing and decreasing on 17 dah. Amylase activity is detected on 3 dah, presenting fluctuations until 45 dah, where it reaches its maximum activity. Acid and alkaline phosphatases are detected from 3 dah and reach a maximum activity between 13 and 19 dah. The SDS-PAGE electrophoresis revealed six types of bands in the alkaline proteases, with molecular weight between 113.4 and 20.4 kDa. First three bands appear on 6 dah, but it is until 11 dah when all isoforms appear. Based on these results, it is considered that this species completes its digestive enzymatic machinery from day 9 after hatching, therefore is recommended to perform the transition from live feed to inert feed at 15 dah.