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Early implant failure and bone resorption may occur in load-bearing conditions as a result of stress shielding brought on by a mismatch in the bone-Ti-implant modulus. A review with a novel multidisciplinary perspective is proposed in this work, which considers recent developments of β-Titanium alloys and new trends in novel microstructures, processing techniques, properties of dense and porous substrates, as well as the relationship between all these aspects and performance in service, in terms of improved its biomechanical and bio-functional balance. In addition to highlighting several modern and historical uses for Ti alloys, this review covers many cutting-edge novel β-Ti alloys and uses that promise to exceed historical standards. Also, it deepens through several important properties of these alloys, including toxicity of alloying elements, phase stability, thermo-mechanical processing, heat treatment, surface, and stress-induced modifications. The stiffness, hardness, fatigue and wear resistance, corrosion behaviour, biocompatibility, and manufacturing and surface modification effects on these parameters are also emphasized. In-vitro and in-vivo assays have been added to highlight important aspects of bioactivity and antibacterial behaviour, and future significant research areas are suggested along with new techniques to ensure the successful clinical application of β-Ti alloys.

Addressing large bone segmental defects remains a profound challenge in orthopaedic surgery, demanding graft designs that mirror patient-specific defects while ensuring vascularization, osteoconduction, and structural integrity. Conventional approaches fall short in achieving this level of customization and functionality. This work leverages fuse filament fabrication (FFF) to fabricate innovative yttria stabilize zirconia graft designs that combine several strategies to tackle these multifaceted challenges. Graft designs ingeniously incorporate dense and porous structures mimicking the intricate architecture of natural bone for improved structural integrity and different ridges and protrusions to enhance the fixation. Additionally, these grafts undergo infiltration with PCL/PVA/AgNPs composite polymers, enriching biocompatibility, structural integrity, and antibacterial properties, fostering conducive conditions for optimal bone growth. Attaining printable filaments with YSZ powders below 50 nm and loads reaching 50 vol% marks a pioneering advancement in bone graft fabrication via Fused Filament Fabrication (FFF). This enabled high densification and low grain size at reduced sintering temperatures, imperative to achieve high mechanical performance. The biodegradation capacity of biopolymers in PBS and their role in the mechanical behaviour of grafts have been assessed, demonstrating the beneficial potential of the multicomponent graft proposed reaching strength values of 90–105 MPa.

We determined the effects of sodium propionate (SP) added to the diets of Atractosteus tropicus juveniles with respect to the growth, survival, digestive enzyme activity, and expression of genes that are associated with the immune system. Five treatments (0, 0.5, 1.0, 1.5, and 2.0%) were evaluated in triplicate on 180 fish (3.65 ± 0.12 g) distributed among 15 (70 L) tanks. The juveniles were fed five times a day with 5% feed in relation to the biomass of the organism. The treatment with 0.5% SP showed a final weight value of 25.7 ± 4.5 g, absolute weight of gain (AWG) of 21.93 ± 4.39 g, and specific growth rate (SGR) of 3.1 ± 0.26. Treatments with 1.5 and 2.0% SP showed the highest survival (91.6%). The control group (0%) showed a greater activity of lipases. There was a tendency that the highest activity of alkaline proteases and chymotrypsin occurred in the 0 and 0.5% treatments. The maximum relative expression of the genes ocln, muc2, and nod2 occurred in the 1.5% treatment. The inclusion of SP in the diet of A. tropicus juveniles could benefit the activity of some digestive enzymes as well as the expression of genes related to the function of the intestinal barrier, therefore benefitting the survival of the organisms.

En esta investigación se presenta el análisis y comparación de los resultados reportados en la literatura de 1987 al 2023 relacionados con la capacidad de absorción de energía específica de columnas tubulares de materiales compuestos, los cuales se clasificaron en tres categorías: a) laminados con fibras en orientación de [0,90], b) laminados con fibras unidireccionales, y 3) laminados con laminados multidireccionales. Se examinó la absorción de energía específica (SEA) y se realizaron comparaciones entre los estudios. Los resultados exhibieron una amplia dispersión en los datos, incluso para configuraciones aparentemente similares. Las diferencias se atribuyen a factores como dimensiones de probetas, materiales utilizados y técnicas de ensayo. Además, se observó la falta de normativas estandarizadas, lo que dificulta la comparación y la identificación de patrones consistentes. Se concluye que la implementación de estándares unificados mejoraría la coherencia y comparabilidad de los resultados, proporcionando una comprensión más profunda de estos materiales en aplicaciones futuras.

IntroductionCrohn’s disease (CD) involves activation of mast cells (MC) and NF-кB in parallel with the PPAR-α/NLRP3 inflammasome/IL-1β pathway in the inflamed colon. Whether polyphenols from maqui (Aristotelia chilensis) represent a natural alternative treatment for CD is unclear. Therefore, we used an animal model of 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced CD-like colitis to investigate protective effects of maqui extract through monitoring NLRP3 inflammasome and MC activation in colon tissue.MethodsMaqui extract was administered via orogastric route to mice after (post-Treatment group) or prior (pre-Treatment group) to TNBS-induction. Colon pathology was characterized by histoarchitectural imaging, disease activity index (DAI), and assessing NF-кB, p-NF-кB, PPAR-α/NLRP3 expression and IL-1β levels.ResultsCompared to mice treated with TNBS alone administration of anthocyanin-rich maqui extract improved the DAI, colon histoarchitecture and reduced both colon wet-weight and transmural inflammation. Induction with TNBS significantly increased colonic NLPR3 inflammasome activation, while co-treatment with maqui extract (either post- or pre-Treatment) significantly downregulated NLRP3, ASC and caspase-1 levels, which manifested as reduced colonic IL-1β levels. Supplemented maqui extract marginally diminished NF-кB activity in epithelial cells but reached statistical significance in immune cells (as judged by decreased NF-кB phosphorylation). PPAR-α signaling was largely unaffected by Maqui whereas MC infiltration into the colon mucosa and submucosa decreased and their level of degranulation was suppressed.ConclusionThese outcomes show the post- and pre- Treatment effect of a polyphenolic extract rich in anthocyanins from maqui the acute phase of TNBS- induced CD-like colitis is linked to suppression of the NLRP3 inflammasome and reduced MC responses. These data indicate that maqui extract represents a potential nutraceutical for the treatment of inflammatory bowel disease (IBD).

The use of β-Titanium alloys to fabricate metal implants with Young's modulus that resembles bone tissues is presented as an alternative to commercially pure titanium or α-Titanium alloys, although it is still necessary to introduce proper implant porosity to reach the Young's modulus of cortical bones. In this work, porous samples were fabricated by loose sintering (0 MPa) and compared to samples manufactured at 1000 MPa, both sintered under the same conditions. Raw powders and sintered samples of the β-Titanium alloy, Ti35Nb7Zr5Ta, were characterized in detail in terms of both physicochemical and microstructural properties. Moreover, the tribo-mechanical behavior of sintered samples was evaluated by performing ultrasound technique, instrumented micro-indentation (P-h curves), and scratch tests. The bio-functional behavior was studied by impedance spectroscopy and contact angle measurements. The results allowed the evaluation of the limits of conventional powder metallurgy (percentage of porosity, size, and morphology of pores), as well as the influence of the porosity and chemical composition to achieve a better biomechanical and bio-functional behavior that would guarantee bone requirements. The Ti35Nb7Zr5Ta alloy showed relatively high electrical impedance values compared to commercially pure titanium, indicating an improved bio-corrosion behavior. Furthermore, wettability measurements indicated that porous disks fabricated by loose sintering exhibit higher hydrophilicity, often associated with a better antibacterial response.

The effect of adding inulin to balanced diets for tropical gar (Atractosteus tropicus) larvae on growth, survival, digestive enzyme activity, and antioxidant activity was evaluated. The diets were supplemented with 0.5, 1.0, 1.5, 2.0, and 2.5% inulin in addition to a control diet (0% inulin). A total of 1800 larvae of A. tropicus distributed in 18 tanks were used; the larvae were fed five times a day (8:00, 11:00, 13:00, 15:00, and 18:00) with Artemia nauplii from the absorption of the yolk (from 3–7 days after hatching, DAH) up to 10 DAH, which was mixed with the experimental feeds from 8–11 DAH (co-feeding) and exclusively with the balanced diets from 12 DAH to 21 DAH. Larvae fed the control diet (0% inulin) had the highest growth in weight and length, followed by fish fed the 2.5 and 2.0% inulin inclusions. However, survival showed that the fish fed with the inclusion of 2.5% inulin had the highest percentage (34.7%) compared to the rest of the treatments. On the other hand, the highest digestive enzymatic activities (acid and alkaline proteases, amylase, and lipase) were recorded in the larvae fed with 2 and 2.5% inulin. Likewise, catalase (CAT) and superoxide dismutase (SOD) activities were higher in larvae fed the control diet with 0% inulin. Supplementation of 2.0% to 2.5% inulin in the diet is recommended for A. tropicus larvae as it improves survival and digestive enzyme activity during this early stage of life.

En este trabajo se presenta resultados sobre la evaluación de la resistencia/peso en una viga tipo I de material compuesto híbrido con fibras de algodón/vidrio (64% fibras de algodón y 36% fibras de vidrio). Se realizaron simulaciones numéricas a flexión a través del programa ANSYS y una prueba experimental a flexión en la máquina de ensayos Shimadzu AG-Xplus 100kN. Los resultados mostraron que es posible obtener una geometría optimizada dentro de la viga a través de la remoción estratégica de zonas de material sin comprometer la integridad estructural. Además, la prueba experimental a flexión en la viga de material compuesto mostró un valor superior en la relación de resistencia/peso (44) en comparación con la viga optimizada de aluminio 6061-T6 (39.65); este comportamiento se atribuye a que los materiales compuestos reforzados con fibras son generalmente menos densos en comparación con los metales, y a la distribución de las fibras de algodón y vidrio dentro de la viga.

Summary: Drought is a critical issue in modern agriculture; therefore, there is a need to create crops with drought resilience. The complexity of plant responses to abiotic stresses, particularly in the field of brassinosteroid (BR) signalling, has been the subject of extensive research. In this study, we unveil compelling insights indicating that the BRASSINOSTEROID‐INSENSITIVE 1 (BRI1) receptor in Arabidopsis and Sorghum plays a critical role as a negative regulator of drought responses. Introducing untargeted mutation in the sorghum BRI1 receptor (SbBRI1) effectively enhances the plant's ability to withstand osmotic and drought stress. Through DNA Affinity Purification sequencing (DAP‐seq), we show that the sorghum BRI1‐EMS‐SUPPRESSOR 1 (SbBES1) transcription factor, a downstream player of the BR signalling, binds to a conserved G‐box binding motif, and it is responsible for regulating BR homeostasis, as its Arabidopsis ortholog AtBES1. We further characterized the drought tolerance of sorghum bri1 mutants and decipher SbBES1‐mediated regulation of phenylpropanoid pathway. Our findings suggest that SbBRI1 signalling serves a dual purpose: under normal conditions, it regulates lignin biosynthesis by SbBES1, but during drought conditions, BES1 becomes less active, allowing the activation of the flavonoid pathway. This adaptive shift improves the photosynthetic rate and photoprotection, reinforcing crop adaptation to drought. [ABSTRACT FROM AUTHOR]

The intracohort cannibalism present in tropical gar larvae (A. tropicus) generates great problems in its culture, as in other fish species around the world. The addition of tryptophan (Trp) (10, 20, and 30 g/kg) and a control diet (CD) without Trp were evaluated in A. tropicus larvae regarding growth, survival, cannibalism, behavior, digestive enzymatic activity, and genes related to aggressiveness and/or cannibalism in two stages: 0–13 days after hatching (DAH); and only cannibals (14–24 DAH). In the first stage, no differences were observed in growth parameters; cannibalism was lower with the use of Trp, with the lowest percentage being the 10 g/kg Trp treatment (56.75 ± 2.47%) compared to CD (64.75 ± 1.76%). In the second stage, survival was greater in 10 g/kg Trp (75.00 ± 7.07%) than in CD (23.33 ± 5.77%). Thus, cannibalism was lower with 10 g/kg Trp (20.0 ± 10.0%) compared to CD (76.66 ± 5.77%). Cannibal larvae fed with 10 g/kg Trp had a greater enzymatic activity in acid and alkaline proteases and leucine aminopeptidase, as well as the overexpression of avpi1, crh, and htr1a and the subexpression of tph1, th, sstr1, and hdc (p < 0.05). No aggressive behaviors were recorded in the larvae fed with the 10 g/kg Trp treatment, unlike those fed with CD. The use of 10 g/kg Trp improves survival and reduces cannibalism in A. tropicus larvae.

Measurement(s) gene expression • metabolite Technology Type(s) gene expression detection method • gas chromatography time-of-flight mass spectrometry Factor Type(s) time • drought • genotype • plant tissue Sample Characteristic - Organism Arabidopsis thaliana Sample Characteristic - Environment greenhouse soil Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.17705021

Esta investigación pretende reflejar la etapa de florecimiento que vive la ficción sonora en España, un género que tuvo su época más esplendorosa en los años 50 y 60 del siglo pasado. Entonces, en una radio controlada por la censura, reinaba en las parrillas de programación. La llegada de la televisión, primero, y de la libertad informativa que trajo consigo la democracia, después, dieron lugar a su declive y a su práctica desaparición. Sin embargo, a partir de 2014, paralelamente al auge del podcast en EEUU, este formato de audio estaría convirtiéndose en un factor clave para su despertar tras cuatro décadas de letargo. Con la finalidad de investigar este fenómeno, se ha procedido, por un lado, a entrevistar a los productores de ficción de las cuatro emisoras generalistas de cobertura nacional: Cadena SER, COPE, Onda Cero y RNE, y, por otra parte, a analizar en profundidad las producciones de los últimos diez años. Entre las conclusiones, destaca el vínculo existente entre la recuperación de los dramáticos y el crecimiento del podcast, así como la preponderancia tanto de las adaptaciones de novelas y películas sobre las creaciones originales, como de las entregas únicas frente a las series. Además, se evidencia cómo el empeño de los profesionales suple las limitaciones empresariales que impiden que haya un mayor volumen de producción.

Aquaculture practices expose fish to several factors that may generate stress, modifying the balance between the production of reactive oxygen species (ROS) and the activity of antioxidant defenses that induce cell damage. Alpha-tocopherol (VE) improves the antioxidant capacity against ROS production in fish. A 50-day trial with longfin yellowtail (Seriola rivoliana) juveniles was conducted to compare the dietary supplementation of 500 mg/kg of VE against a control diet without VE supplementation on growth, lymphoid tissue enzymatic activity, immune-system-related gene expression, and the histology of the liver and spleen. Growth, weight gain, specific growth rate, feed conversion rate, and survival did not show significant differences (p > 0.05) among treatments. Fish fed with an α-tocopherol-enriched diet showed a higher enzymatic activity of superoxide dismutase in the liver (p < 0.05) and a lower percentage of melanomacrophage coverage area in the lymphoid organs (p < 0.05). Overexpression was observed of MyD88 and il-10 in the spleen, and il-1b in the liver in fish fed 500 mg/kg of VE, as well as overexpression of Toll-like 3 in the head kidney, spleen, and liver in fish fed the control diet. Dietary supplementation with VE reduces the effects of oxidative stress and improves lymphoid tissue defense and immune-related gene expression in S. rivoliana.

Tropical gar, Atractosteus tropicus Gill, 1863, is an ancient freshwater fish that is commercially cultivated in southern Mexico. Currently, there is a specific diet for its culture; however, the addition of probiotics has not been investigated. The objective of this study was to evaluate the supplementation of live yeast Debaryomyces hansenii for A. tropicus juveniles on growth, productive parameters, survival, somatic index, digestive enzyme activity, and immune system gene expressions (interleukin 10, il-10, Transforming growth factor β1, tgf-β1, and β2 microglobulin, b2m). Three experimental diets increased the dose of live yeast (0.5, 1.0, and 1.5%; 1014, 1015, and 1016 CFU g diet–1, respectively) and a control diet (CD; without yeast) were designed. Daily weight gain and specific growth rate were higher in fish fed with CD and 0.5% D. hansenii. High activities of trypsin, chymotrypsin LAP, and α-amylase, as well as overexpression of il-10 in the spleen, were detected in fish feed 0.5% D. hansenii. The inclusion of D. hansenii had no positive effect on aquaculture for A. tropicus, lower doses should be tested to optimize the diet.

Abstract Bay snook (Petenia splendida) is a carnivorous cichlid species with excellent economic value in Southeast Mexico. Although this species presents an excellent potential for commercial aquaculture, the information about its nutritional, physiological, and reproductive metabolic pathways is meager. The current study focuses on the expression of glucose transporter 2 (glut2) in embryos and larvae at 5, 10, 15-, 20-, 25-, and 30-days post-hatch (dph) and in the liver, intestine, kidney, muscle, heart, testicle, gill, stomach, pancreas, and brain of adult fish. The partial sequence of glut2 was obtained, and specific qPCR primers were designed. In embryos, the expression was lower compared to larvae at 5, 15, and 20 dph. The highest expression in larvae occurred at 20 dph and the lowest at 25 and 30 dph. Maximum expression levels in adults occurred in the liver and intestine. Our results show that glut2 is expressed differentially across tissues of adult bay snook, and it fluctuates during larval development.

Currently, the field of medicine is drastically advancing, mainly due to the progress in emerging areas such as nanomedicine, regenerative medicine, and personalized medicine. For example, the development of novel drug delivery systems in the form of nanoparticles is improving the liberation, absorption, distribution, metabolism, and excretion (LADME) properties of the derived formulations, with a consequent enhancement in the treatment efficacy, a reduction in the secondary effects, and an increase in compliance with the dosage guidelines. Additionally, the use of biocompatible scaffolds is translating into the possibility of regenerating biological tissues. Personalized medicine is also benefiting from the advantages offered by additive manufacturing. However, all these areas have in common the need to develop novel materials or composites that fulfill the requirements of each application. Therefore, the aim of this Special Issue was to identify novel materials/composites that have been developed with specific characteristics for the designed biomedical application.

This research provides a detailed analysis of the COVID-19 spread across 14 Latin American countries. Using time-series analysis and epidemic models, we identify diverse outbreak patterns, which seem not to be influenced by geographical location or country size, suggesting the influence of other determining factors. Our study uncovers significant discrepancies between the number recorded COVID-19 cases and the real epidemiological situation, emphasizing the crucial need for accurate data handling and continuous surveillance in managing epidemics. The absence of a clear correlation between the country size and the confirmed cases, as well as with the fatalities, further underscores the multifaceted influences on COVID-19 impact beyond population size. Despite the decreased real-time reproduction number indicating quarantine effectiveness in most countries, we note a resurgence in infection rates upon resumption of daily activities. These insights spotlight the challenge of balancing public health measures with economic and social activities. Our core findings provide novel insights, applicable to guiding epidemic control strategies and informing decision-making processes in combatting the pandemic.

Adolescence is a period during which body composition changes deeply. Selenium (Se) is an excellent antioxidant trace element related to cell growth and endocrine function. In adolescent rats, low Se supplementation affects adipocyte development differently depending on its form of administration (selenite or Se nanoparticles (SeNPs). Despite this effect being related to oxidative, insulin-signaling and autophagy processes, the whole mechanism is not elucidated. The microbiota–liver–bile salts secretion axis is related to lipid homeostasis and adipose tissue development. Therefore, the colonic microbiota and total bile salts homeostasis were explored in four experimental groups of male adolescent rats: control, low-sodium selenite supplementation, low SeNP supplementation and moderate SeNPs supplementation. SeNPs were obtained by reducing Se tetrachloride in the presence of ascorbic acid. Supplementation was received orally through water intake; low-Se rats received twice more Se than control animals and moderate-Se rats tenfold more. Supplementation with low doses of Se clearly affected anaerobic colonic microbiota profile and bile salts homeostasis. However, these effects were different depending on the Se administration form. Selenite supplementation primarily affected liver by decreasing farnesoid X receptor hepatic function, leading to the accumulation of hepatic bile salts together to increase in the ratio Firmicutes/Bacteroidetes and glucagon-like peptide-1 (GLP-1) secretion. In contrast, low SeNP levels mainly affected microbiota, moving them towards a more prominent Gram-negative profile in which the relative abundance of Akkermansia and Muribaculaceae was clearly enhanced and the Firmicutes/Bacteroidetes ratio decreased. This bacterial profile is directly related to lower adipose tissue mass. Moreover, low SeNP administration did not modify bile salts pool in serum circulation. In addition, specific gut microbiota was regulated upon administration of low levels of Se in the forms of selenite or SeNPs, which are properly discussed. On its side, moderate-SeNPs administration led to great dysbiosis and enhanced the abundance of pathogenic bacteria, being considered toxic. These results strongly correlate with the deep change in adipose mass previously found in these animals, indicating that the microbiota–liver–bile salts axis is also mechanistically involved in these changes.

The spread of antibiotic resistance among human and animal pathogens is one of the more significant public health concerns. Moreover, the restrictions on the use of particular antibiotics can limit the options for the treatment of infections in veterinary clinical practice. In this context, searching for alternative antimicrobial substances is crucial nowadays. In this study, 4,4′-dihydroxy-azobenzene (DHAB) was tested for its potential in vitro as an antimicrobial agent against two relevant human and animal pathogens, namely Staphylococcus aureus and Staphylococcus pseudintermedius. The values of minimal inhibitory concentration (MIC) were 64 and 32 mg/L respectively, and they comparable to other azo compounds of probed antimicrobial activity. In addition, the minimal bactericidal concentrations (MCB) were 256 and 64 mg/L. The mechanism by which DHAB produces toxicity in staphylococci has been investigated. DHAB caused membrane damage as revealed by the increase in thiobarbituric acid reactive substances (TBARS) such as malondialdehyde. Furthermore, differential induction of the enzymes peroxidases and superoxide dismutase in S. aureus and S. pseudintermedius suggested their prevalent role in ROS-scavenging due to the oxidative burst induced by this compound in either species. In addition, this substance was able to inhibit the formation of biofilms by both bacteria as observed by colorimetric tests and scanning electron microscopy. In order to assess the relevance of DHAB against clinical strains of MRSA, 10 clinical isolates resistant to either methicillin or daptomycin were assayed; 80% of them gave values of CMI and CMB similar to those of the control S. aureus strain. Finally, cutaneous plasters containing a composite formed by an agar base supplemented with DHAB were designed. These plasters were able to inhibit in vitro the growth of S. aureus and S. pseudintermedius, particularly the later, and this suggests that this substance could be a promising candidate as an alternative to antibiotics in the treatment of animal skin infections, as it has been proven that the toxicity of this substance is very low particularly at a dermal level.

Currently agriculture has difficulty keeping up with the demand for food around the world, which has generated a boom in the development of sustainable alternatives for producing food and caring for the environment. Therefore, the present study aims to show a backyard system comprising 50 cm × 50 cm pinewood boxes where maize and peanut were tested under control and compost conditions. The experiments were carried out for nine months starting from compost production and the sowing of the crops, which were irrigated with temporary rain. The compost was produced by converting ~213 kg of organic residues into ~300 kg of mature compost. The fertilizer treatment consisted of two doses of compost (1 kg doses). The developing plants were compared between conditions in both crops. In addition, the nutritional values of the compost and compost and soil were evaluated. Interestingly, the correlation analyses of the morphological properties of the soils showed that the effects of the nutrients were positively associated with the morphology of the crops studied. Finally, the yield produced for maize was 9 kg/m2 and 6.6 kg/m2 and that for peanuts was 184 g/m2 and 73 g/m2 under compost and control conditions, respectively. We consider that the development of new alternatives for producing food in times of crisis or situations of limited resources is necessary for the development of humanity and the care of the environment.

In current digital ecosystem, sound is gaining prominence through new formats such as podcasting, born in the era of mobility. Formats that can share elements, characteristics, dynamics of work and consumption with other traditional radio formats, such as reports, docudramas or the radio soap opera. This article aims to analyze whether the strength of human reach storytelling is a common starting point in analogic reports and in fictional and non-fiction podcasts, both on audio platforms and on conventional radio. For this, three podcast are proposed as case study: ‘Sin mi identidad’ (2018, COPE network), ‘Lo conocí en un Corpus’ (2017, Podium Podcast) and ‘Las tres muertes de mi padre’ (2017, Cuonda). The methodology is classified as descriptive and qualitative and includes semi-structured interviews with key subjects in the process of the three spaces considered as objects of study. In the analyzed cases it can be stated that, although reports and fiction and nonfiction podcasts are different products, they share similarities of production, documentation and recording. Also, all have as starting point a real story, even when podcasts are fiction.

Ficha técnica: Luis Miguel Pedrero Esteban y Ana Pérez Escoda (Editores) Editorial Civitas y Thomson Reuters ARANZADI (versión digital) 359 pp. ISBN 978-84-1345-825-0

ABSTRACT In the Southeast of Mexico, there are many native cichlids with commercial interest such as redhead cichlid (Vieja melanurus) and twoband cichlid (V. bifasciata), which have a great local demand and excellent meat quality. However, it is necessary to implement their culture based on nutrition studies and digestive biochemistry. This study’s objective was to characterize these two cichlids’ digestive proteases (pH, temperature, and inhibitors) through biochemistry techniques. Results showed that V. melanurus and V. bifasciata have a digestive capacity analogous to other omnivore fishes, where the optimal pH values of stomach proteases (4 and 2, respectively) and intestinal proteases (6 and 12, respectively), the optimal temperature of acid (35°C and 55°C, respectively) and alkaline proteases (45°C and 55°C, respectively) are quite similar. Both species presented high thermal and pH stabilities. Inhibition showed that V. melanurus is more sensitive to specific inhibitors for alkaline proteases than V. bifasciata. In conclusion, V. bisfasciata and V. melanurus have different digestive protease patterns. Both species can hydrolyze different protein ingredients to formulate a specific diet. Nevertheless, V. bifasciata is more resistant to the presence of inhibitors, which allow it to include vegetable proteins in its diet.

Marine organisms are a valuable source of new compounds, many of which have remarkable biotechnological properties, such as microalgae and cyanobacteria, which have attracted special attention to develop new industrial production routes. These organisms are a source of many biologically active molecules in nature, including antioxidants, immunostimulants, antivirals, antibiotics, hemagglutinates, polyunsaturated fatty acids, peptides, proteins, biofuels, and pigments. The use of several technologies to improve biomass production, in the first step, industrial processes schemes have been addressed with different accomplishments. It is critical to consider all steps involved in producing a bioactive valuable compound, such as species and strain selection, nutrient supply required to support productivity, type of photobioreactor, downstream processes, namely extraction, recovery, and purification. In general, two product production schemes can be mentioned; one for large amounts of product, such as biodiesel or any other biofuel and the biomass for feeding purposes; the other for when the product will be used in the human health domain, such as antivirals, antibiotics, antioxidants, etc. Several applications for microalgae have been documented. In general, the usefulness of an application for each species of microalgae is determined by growth and product production. Furthermore, the use of OMICS technologies enabled the development of a new design for human therapeutic recombinant proteins, including strain selection based on previous proteomic profiles, gene cloning, and the development of expression networks. Microalgal expression systems have an advantage over traditional microbial, plant, and mammalian expression systems for new and sustainable microalga applications, for responsible production and consumption.

This study was conducted to investigate the effects of dietary fructooligosaccharides (FOS) on the growth, survival rate, digestive enzyms activity, and the expression of intestinal barrier function genes in tropical gar (Atractosteus tropicus) larvae. A total of 960 larvae (0.030 ± 0.006 g) were fed three diets supplemented with increasing FOS concentrations (2.5, 5, and 7.5 g kg−1) and a control diet for 15 days. Results revealed that a 7.5 g kg−1 FOS supplementation improved weight gain, specific growth rate, and survival rate (p < 0.05). Furthermore, 5 g kg−1 FOS supplementation increased alkaline protease and amylase activities and induced an upregulation of the claudin-17 gene expression (p < 0.05). Meanwhile, the inclusion of 7.5 g kg−1 FOS induced the upregulation of mucin 2 (muc-2), and the tight junction genes zo-2 and claudin-3 (p < 0.05). In addition, 2.5, 5, and 7.5 g kg−1 FOS promoted the downregulation of the claudin-15 gene expression (p < 0.05). At the same time, FOS inclusion did not increase the pro-inflammatory cytokine il-8 expression. We can conclude that 7.5 g kg−1 FOS supplementation improves growth performance, survival rate, and digestive capacity, and could contribute to the reinforcement of the intestinal barrier function of Tropical gar larvae.

Despite the increasing progress achieved in the last 20 years in both the fabrication of porous dental implants and the development of new biopolymers for targeting drug therapy, there are important issues such as bone resorption, poor osseointegration, and bacterial infections that remain as critical challenges to avoid clinical failure problems. In this work, we present a novel microtechnology based on polycaprolactone microspheres that can adhere to porous titanium implant models obtained by the spacer holder technique to allow a custom biomechanical and biofunctional balance. For this purpose, a double emulsion solvent evaporation technique was successfully employed for the fabrication of the microparticles properly loaded with the antibacterial therapeutic agent, rose bengal. The resulting microspheres were infiltrated into porous titanium substrate and sintered at 60 °C for 1 h, obtaining a convenient prophylactic network. In fact, the sintered polymeric microparticles were demonstrated to be key to controlling the drug dissolution rate and favoring the early healing process as consequence of a better wettability of the porous titanium substrate to promote calcium phosphate nucleation. Thus, this joint technology proposes a suitable prophylactic tool to prevent both early-stage infection and late-stage osseointegration problems.

Background: Sugarcane and maize are two main crops in Mexico, and the soil characteristics are important for their proper grow. Soil suitability is assessed through indicators which are chemical, physical and biological. Objective: We compared physical, chemical and microbiological soil properties in two agroecosystems, one with sugarcane and one with maize, under irrigation and rainfed conditions, so as to detect soil quality changes in each condition. Methodology: Soil samples were evaluated for pH, N, P, K, Ca, Mg, Na, organic matter, cationic exchange and texture, based on the NOM-021-RECNAT-2000. The number of microorganisms was quantified in each agroecosystem, using four culture media. Data was examined with an analysis of variance and Tukey mean test (P ≤ 0.05). Results: Soil quality was low in localities with maize, and there were not statistical differences among them; but it was better in sugarcane under rainy season-based cropping system than under irrigation. More microorganism colonies were found in maize under irrigation and sugarcane under rainy season-based cropping system. Implications: It is important to establish conservation measures that allow buffering and preserving soil and nutrient losses to maintain their productive capacity, especially in soils with more years of production. Conclusions: Soils under rainy season-based cropping system, with both agroecosystems, presented better nutritional contents in comparison with those under irrigation. The largest number of microorganisms in corn under irrigation and sugarcane under rainfed conditions could be because the pH was higher than the other two agroecosystems.

En la actualidad se necesita contar con instrumentos que consideren el conocimiento local para la caracterización de agroecosistemas (AES). Ante tal contexto, la clasificación campesina de tierras de Ortiz-Solorio, Pájaro y Ordaz (1991), como parte de la disciplina etnoedafológica, complementa el conocimientolocal con el conocimiento técnico. Esta combinación suministra información detallada para la cartografía, clasificación, descripción de uso, manejo y aprovechamiento no solo de tierras sino de los componentes de cualquier AES. A partir de esto, se pueden obtener insumos para describir a nivel de ejido y de finca la estructura de AES con información actualizada y de primera mano. Se aplicó este método en el ejido Mafafas, ubicado en el municipio de Tepetlán, Veracruz, que presenta problemas de disminución de la productividad de café. Se realizó una clasificación campesina de tierras y también se empleó el método etnoedafológico para recopilar información y caracterizar la estructura de agroecosistemas cafetaleros. Se obtuvo un mapa a escala 1:10 000 y en total se representan ocho clases de tierra con cuatro tipos predominantes de uso del suelo. Además, se analizaron once fincas que mostraron distintas estructuras, aunque muestran patrones en común. Se mostrará una alternativa para caracterizar AES con un método sistémico que se vale del conocimiento local y que resulta de fácil aplicación. Los resultados obtenidos de este procedimiento respaldan la idea de que todos los ejidos requieren un estudio con este enfoque, que sirva como base para la planeación local y el desarrollo del campo mexicano.

Complexes {Ag[NHCMes,R]}n (R = H, 2a; Me, 2b and 2b’; iPr, 2c; iBu, 2d), were prepared by treatment of imidazolium precursor compounds [ImMes,R] (2-(3-mesityl-1H-imidazol-3-ium-1-yl)acetate, 1a, (S)-2-alkyl(3-mesityl-1H-imidazol-3-ium-1-yl)acetate, 1b–d, and (R)-2-methyl(3-mesityl-1H-imidazol-3-ium-1-yl)acetate, 1b’, with Ag2O under appropriate conditions. They were characterised by analytical, spectroscopic (IR, 1H, and 13C NMR and polarimetry), and X-ray methods (2a). In the solid state, 2a is a one-dimensional coordination polymer, in which the silver(I) cation is bonded to the carbene ligand and to the carboxylate group of a symmetry-related Ag[NHCMes,H] moiety. The coordination environment of the silver centre is well described by the DFT study of the dimeric model {Ag[NHCMes,H]}2. The antimicrobial properties of these complexes were evaluated versus Gram-negative bacteria E. coli and P. aeruginosa. From the observed MIC and MBC values (minimal inhibitory concentration and minimal bactericidal concentration, respectively), complex 2b’ showed the best antimicrobial properties (eutomer), which were significantly better than those of its enantiomeric derivative 2b (distomer). Additionally, analysis of MIC and MBC values of 2a–d reveal a clear structure–antimicrobial effect relationship. Antimicrobial activity decreases when the steric properties of the R alkyl group in {Ag[NHCMes,R]}n increase.