Characterizing atherosclerotic tissues: in silico analysis of mechanical properties using intravascular ultrasound and inverse finite element methods.

Atherosclerosis is a prevalent cause of acute coronary syndromes that consists of lipid deposition inside the artery wall, creating an atherosclerotic plaque. Early detection may prevent the risk of plaque rupture. Nowadays, intravascular ultrasound (IVUS) is the most common medical imaging technology for atherosclerotic plaque detection. It provides an image of the section of the coronary wall and, in combination with new techniques, can estimate the displacement or strain fields. From these magnitudes and by inverse analysis, it is possible to estimate the mechanical properties of the plaque tissues and their stress distribution. In this paper, we presented a methodology based on two approaches to characterize the mechanical properties of atherosclerotic tissues. The first approach estimated the linear behavior under particular pressure. In contrast, the second technique yielded the non-linear hyperelastic material curves for the fibrotic tissues across the complete physiological pressure range. To establish and validate this method, the theoretical framework employed in silico models to simulate atherosclerotic plaques and their IVUS data. We analyzed different materials and real geometries with finite element (FE) models. After the segmentation of the fibrotic, calcification, and lipid tissues, an inverse FE analysis was performed to estimate the mechanical response of the tissues. Both approaches employed an optimization process to obtain the mechanical properties by minimizing the error between the radial strains obtained from the simulated IVUS and those achieved in each iteration. The second methodology was successfully applied to five distinct real geometries and four different fibrotic tissues, getting median R 2 of 0.97 and 0.92, respectively, when comparing the real and estimated behavior curves. In addition, the last technique reduced errors in the estimated plaque strain field by more than 20% during the optimization process, compared to the former approach. The findings enabled the estimation of the stress field over the hyperelastic plaque tissues, providing valuable insights into its risk of rupture.

Kraft lignin and its derivates - A study on the adsorption of mono and multielement metals, potential use for noble metal recycling and an alternative material for solid base catalyst.

Lignin is a natural polymer containing diverse functional groups and displaying an affinity for metals. Kraft lignin can be used as a carbon source, as a cleaving lignin structure for aromatic macromers or in the addition and modification of functional groups by the development of new active chemical sites. In this context, the aim of the present study is to investigate the adsorption of mono and multi-element metals solutions on lignin derivatives (unmodified Kraft lignin, acetylated Kraft lignin, charcoal Kraft lignin and activated carbon Kraft lignin). Parameters that affect adsorption processes, such as pH, contact time and adsorbent dose, were optimized in each case. The best adsorption condition was obtained at pH 7.00, a contact time of 120 min and with adsorbent dose of 30 mg. Also, unmodified Kraft lignin shows high adsorption selectivity (99%) for gold and palladium in acidic solutions. Acetylated and charcoal Kraft lignin resulted in lower adsorption levels in comparison with unmodified Kraft lignin. Activated carbon, however, reached adsorptions of over 86% for all metals. Finally, unmodified Kraft lignin impregnated with palladium presents a promising heterogeneous support in the Suzuki-Miyaura reaction.

Preservation of high pressure pasteurised milk by hyperbaric storage at room temperature versus refrigeration on inoculated microorganisms, fatty acids, volatile compounds and lipid oxidation.

High pressure pasteurised (HPP) milk was stored by hyperbaric storage at room temperature (HS/RT) (50-100 MPa at 20 °C) and compared with refrigeration (RF), to assess the effect on two pathogens surrogates and a pathogenic, up to 120 days, and on fatty acids, volatile organic compounds (VOCs) and secondary lipid oxidation over 60 days. HS/RT (75-100 MPa) was able to inactivate at least 6.68/6.31/6.03 log CFU/mL of Escherichia coli/Listeria innocua/Salmonella Senftenberg (to below the detection limit), while RF resulted only in minor changes. Overall, fatty acids profile remained stable under HS/RT, although secondary lipid oxidation showed slightly higher values. In addition, both HS/RT and RF showed stable and similar VOCs profiles and off-flavour indicative compounds were not detected, except for the lowest pressure (50 MPa) after 40 days. HS/RT preserved HPP milk with enhanced microbial safety, shelf-life and quality compared to RF, being in addition quasi-energetically costless and more sustainable than RF.

Low-pressure long-time or moderate pressure pasteurization at room temperature by hyperbaric inactivation as a new nonthermal preservation approach - A case study on milk.

A new nonthermal food pasteurization approach is here presented for the first time, proposed to be called low-pressure long-time (LPLT) pasteurization or moderate pressure pasteurization (MPP) by hyperbaric inactivation (HI). To test this novel pasteurization process on raw milk, MPP by HI was carried out at three different pressure levels (150, 200 and 250 MPa), over 24 h, at naturally variable uncontrolled room temperature (≈20 °C) and compared with high pressure processing (HPP) at 600 MPa (one cycle for 90 s and a second cycle of 120 s) followed by storage under refrigeration for 21 days. Based on the results obtained, MPP at 250 MPa over 24 h caused higher microbial inactivation on total aerobic mesophiles (TAM), lactic acid bacteria (LAB) and Enterobacteriaceae (ENT) (of at least 2.2, 1.7 and 1.3 log CFU/mL, respectively) than HPP (1.1, 1.0 and 1.2 log CFU/mL, for the same microorganisms). Moreover, MPP showed a clear reduction of inoculated microorganisms to below the detection limit, in only 16 h for all pressures with reductions of at least 5.7, 5.4 and 5.5 for Listeria innocua, Salmonella senftenberg, and Escherichia coli, respectively. Additionally, during preservation under refrigeration, MPP samples (200 MPa and 250 MPa), maintained lower TAM/LAB/ENT compared to HPP, being the counts below the quantification/detection limit for at least 21 days for MPP by HI. MPP (200 MPa and 250 MPa) resulted also in counts below the detection limit for the inoculated microorganisms up to at least 21 days under refrigeration. The results of MPP by HI are very promising as a new nonthermal food pasteurization, since over 5 log reduction of vegetative bacteria were achieved, with counts maintained below the quantification/detection limit for at least 21 days under refrigeration.

Hyperbaric storage at room like temperatures as a possible alternative to refrigeration: evolution and recent advances.

From 2012, the preservation of food products under pressure has been increasingly studied and the knowledge acquired has enlarged since several food products have been studied at different storage conditions. This new food preservation methodology concept called Hyperbaric Storage (HS) has gain relevance due to its potential as a replacement or an improvement to the conventional cold storage processes, such as the traditional refrigeration (RF), or even frosting, from the energetic savings to the reduction of the carbon foot-print. Briefly, HS is capable to inhibit the microbial proliferation or its inactivation which results in the extension of the shelf-life of several food products when compared to RF. Moreover, the overall quality parameters seem not to be affected by HS, being the differences detected on samples over storage similar to lower when compared to the ones stored at RF. This review paper aims to gather data from all studies carried out so far regarding HS performance, mainly at room temperature on fruit juices, meat and fisheries, as well on dairy products and ready-to-eat meals. The HS advantages as a new food preservation methodology are presented and explained, being also discussed the industrial viability and environmental impact of this methodology, as well its limitations.

Inmunoterapia con ácaros Valergen por vía sublingual y subcutánea en pacientes alérgicos. Cabaiguán 2010-2019 / Sublingual and subcutaneous Valergen mite immunotherapy in allergic patients in Cabaiguán 2010-2019

RESUMEN Fundamento: La inmunoterapia consiste en la administración de dosis crecientes del alérgeno para controlar la sensibilidad hacia este. Objetivo: Describir el comportamiento de la inmunoterapia por vía subcutánea o sublingual a ácaros. Metodología: Estudio retrospectivo realizado en Cabaiguán, periodo de 2010 a 2019, el universo de 267 pacientes con pruebas positivas a ácaros y la muestra de 53 pacientes. Los datos se obtuvieron del registro de datos. Resultados: Usó la vía sublingual el 60.4 %, predominó el grupo de edad entre 5-18 años (41.5 %), la vía subcutánea se utilizó en un 39.6 %, fue más frecuente en el sexo masculino (58.5 %). La vía subcutánea se indicó mayoritariamente en la rinitis alérgica (20.7 %) y la sublingual en el asma (32.1 %); para ambas, fue el Dermatofagoide pteronyssinus el ácaro de mayor sensibilidad y utilización (43.4 %), el tiempo de administración dominante fue de 3 años (67.9 %). El control de los síntomas se alcanzó con la vía sublingual (37.7 %). En la vía sublingual no se presentaron eventos adversos en el 43.3 %, con la vía subcutánea 11.3 % de los eventos adversos fueron locales y 7.6 % sistémicos leves. Conclusiones: La vía sublingual fue la más utilizada, la de mayor control de los síntomas y menos eventos adversos en el estudio.

ABSTRACT Background: Immunotherapy consists of the administration of the allergen increasing doses to control sensitivity towards it. Objective: To describe the behavior of subcutaneous or sublingual immunotherapy to mites. Methodology: Retrospective study carried out in Cabaiguán, from 2010 to 2019, the universe of 267 patients with positive tests to mites and the sample 53 patients. Data were obtained from the data record. Results: 60.4 % used sublingual, the age group between 5-18 years prevailed (41.5 %), the subcutaneous was used in 39.6 %, and it was more frequent in males (58.5 %). The subcutaneous was indicated mainly in allergic rhinitis (20.7 %) and sublingual in asthma (32.1 %); for both, Dermatofagoide pteronyssinus was the highest sensitivity and use mite (43.4 %) the dominant administration time was 3 years (67.9 %). Symptom control was achieved by sublingual (37.7 %). In sublingual, there were no adverse events in 43.3 %, with the subcutaneous, 11.3 % of the adverse events were local and 7.6 % were mild systemic. Conclusions: Sublingual was the most used, the one with the highest control of symptoms and the fewest adverse events in the study.

The Combined Effect of Pressure and Temperature on Kefir Production-A Case Study of Food Fermentation in Unconventional Conditions.

Food fermentation under pressure has been studied in recent years as a way to produce foods with novel properties. The purpose of this work was to study kefir production under pressure (7-50 MPa) at different temperatures (17-32 °C), as a case study of unconventional food fermentation. The fermentation time to produce kefir was similar at all temperatures (17, 25, and 32 °C) up to 15 MPa, compared to atmospheric pressure. At 50 MPa, the fermentation rate was slower, but the difference was reduced as temperature increased. During fermentation, lactic and acetic acid concentration increased while citric acid decreased. The positive activation volumes (Va) obtained indicate that pressure decreased the fermentation rate, while the temperature rise led to the attenuation of the pressure effect (lower Va). On the other hand, higher activation energies (Ea) were observed with pressure increase, indicating that fermentation became more sensitive to temperature. The condition that resulted in a faster fermentation, higher titratable acidity, and higher concentration of lactic acid was 15 MPa/32 °C. As the authors are aware, this is the second work in the literature to study the combined effect of pressure and temperature on a fermentative process.

Sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen / Skin sensitization in allergic patients, using Valergen mite extracts

RESUMEN Fundamento: Las enfermedades alérgicas constituyen un problema de salud mundial y los ácaros se encuentran entre sus principales agentes etiológicos. Objetivo: Describir el comportamiento de la sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen. Metodología: Se realizó una investigación observacional transversal con 488 pacientes alérgicos de edades entre 5 y 55 años, de ambos sexos; a los cuales se les realizaron pruebas cutáneas con extractos alergénicos de ácaros en el período 2010-2017. Resultados: El 90.8 % de los pacientes mostró sensibilización cutánea positiva a los extractos utilizados, el 58.4 % fue del grupo de edades entre 5 y 14 años, el 51.2 % pertenecía al sexo femenino, predominaron los pacientes con rinitis y asma; la sensibilización cutánea en los pacientes con estas patologías alcanzó una positividad del 90.1 % y 90.6 % respectivamente; un 38.5 % de los pacientes tuvo como ácaro con mayor positividad al VALERGEN-DP (Dermatophagoides pteronyssinus). Conclusiones: Los extractos de ácaros VALERGEN-DP (Dermatophagoides pteronyssinus) de producción nacional, mostraron alta sensibilización cutánea en los pacientes alérgicos objeto de estudio; el ácaro de mayor positividad fue el VALERGEN-DP (Dermatophagoides pteronyssinus), seguido del VALERGEN-BT (Blomia tropicalis).

ABSTRACT Background: Allergic diseases are a global health problem and mites are among its main etiological agents. Objective: To describe the behavior of skin sensitization in allergic patients, using Valergen mite extracts. Methodology: A cross-sectional observational investigation was carried out with 488 allergic patients being 5 and 55 years old, from both sexes; which were made skin tests with allergenic extracts of mites in the period 2010-2017. Results: 90.8 % of the patients showed positive skin sensitization to the extracts used, 58.4 % were from between the 5 and 14 age group, 51.2 % were female, patients with rhinitis and asthma predominated; skin sensitization in patients with these pathologies reached a positivity of 90.1 % and 90.6 % respectively; 38.5 % of patients had a mite with greater positivity to VALERGEN-DP (Dermatophagoides pteronyssinus). Conclusions: Nationally produced extracts of VALERGEN-DP mites (Dermatophagoides pteronyssinus) showed high skin sensitization in the allergic patients under study; the most positive mite was VALERGEN-DP (Dermatophagoides pteronyssinus), followed by VALERGEN-BT (Blomia tropicalis).

Sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen / Skin sensitization in allergic patients, using Valergen mite extracts

RESUMEN Fundamento: Las enfermedades alérgicas constituyen un problema de salud mundial y los ácaros se encuentran entre sus principales agentes etiológicos. Objetivo: Describir el comportamiento de la sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen. Metodología: Se realizó una investigación observacional transversal con 488 pacientes alérgicos de edades entre 5 y 55 años, de ambos sexos; a los cuales se les realizaron pruebas cutáneas con extractos alergénicos de ácaros en el período 2010-2017. Resultados: El 90.8 % de los pacientes mostró sensibilización cutánea positiva a los extractos utilizados, el 58.4 % fue del grupo de edades entre 5 y 14 años, el 51.2 % pertenecía al sexo femenino, predominaron los pacientes con rinitis y asma; la sensibilización cutánea en los pacientes con estas patologías alcanzó una positividad del 90.1 % y 90.6 % respectivamente; un 38.5 % de los pacientes tuvo como ácaro con mayor positividad al VALERGEN-DP (Dermatophagoides pteronyssinus). Conclusiones: Los extractos de ácaros VALERGEN-DP (Dermatophagoides pteronyssinus) de producción nacional, mostraron alta sensibilización cutánea en los pacientes alérgicos objeto de estudio; el ácaro de mayor positividad fue el VALERGEN-DP (Dermatophagoides pteronyssinus), seguido del VALERGEN-BT (Blomia tropicalis).

ABSTRACT Background: Allergic diseases are a global health problem and mites are among its main etiological agents. Objective: To describe the behavior of skin sensitization in allergic patients, using Valergen mite extracts. Methodology: A cross-sectional observational investigation was carried out with 488 allergic patients being 5 and 55 years old, from both sexes; which were made skin tests with allergenic extracts of mites in the period 2010-2017. Results: 90.8 % of the patients showed positive skin sensitization to the extracts used, 58.4 % were from between the 5 and 14 age group, 51.2 % were female, patients with rhinitis and asthma predominated; skin sensitization in patients with these pathologies reached a positivity of 90.1 % and 90.6 % respectively; 38.5 % of patients had a mite with greater positivity to VALERGEN-DP (Dermatophagoides pteronyssinus). Conclusions: Nationally produced extracts of VALERGEN-DP mites (Dermatophagoides pteronyssinus) showed high skin sensitization in the allergic patients under study; the most positive mite was VALERGEN-DP (Dermatophagoides pteronyssinus), followed by VALERGEN-BT (Blomia tropicalis).

Sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen / Skin sensitization in allergic patients, using Valergen mite extracts

Las enfermedades alérgicas constituyen un problema de salud mundial y los ácaros se encuentran entre sus principales agentes etiológicos. Describir el comportamiento de la sensibilización cutánea en pacientes alérgicos, utilizando extractos de ácaros Valergen. Se realizó una investigación observacional transversal con 488 pacientes alérgicos de edades entre 5 y 55 años, de ambos sexos; a los cuales se les realizaron pruebas cutáneas con extractos alergénicos de ácaros en el período 2010-2017(AU)

Allergic diseases are a global health problem and mites are among its main etiological agents. To describe the behavior of skin sensitization in allergic patients, using Valergen mite extracts. A cross-sectional observational investigation was carried out with 488 allergic patients being 5 and 55 years old, from both sexes; which were made skin tests with allergenic extracts of mites in the period 2010-2017(AU)

Development of a methodology for reversible chemical modification of silicon surfaces with application in nanomechanical biosensors.

Hypervalent tellurium compounds have a particular reactivity towards thiol compounds which are related to their biological properties. In this work, this property was assembled to tellurium-functionalized surfaces. These compounds were used as linkers in the immobilization process of thiolated biomolecules (such as DNA) on microcantilever surfaces. The telluride derivatives acted as reversible binding agents due to their redox properties, providing the regeneration of microcantilever surfaces and allowing their reuse for further biomolecules immobilizations, recycling the functional surface. Initially, we started from the synthesis of 4-((3-((4-methoxyphenyl) tellanyl) phenyl) amino)-4-oxobutanoic acid, a new compound, which was immobilized on a silicon surface. In nanomechanical systems, the detection involved a hybridization study of thiolated DNA sequences. Fluorescence microscopy technique was used to confirm the immobilization and removal of the telluride-DNA system and provided revealing results about the potentiality of applying redox properties to chalcogen derivatives at surfaces.

Antitumor effect of chiral organotelluranes elicited in a murine melanoma model.

Protease roles in cancer progression have been demonstrated and their inhibitors display antitumor effects. Cathepsins are lysosomal cysteine proteases that have increased expression in tumor cells, and tellurium compounds were described as potent cysteine protease inhibitors and also assayed in several animal models. In this work, the two enantiomeric forms of 1-[Butyl(dichloro)-λ4-tellanyl]-2-[1S-methoxyethyl]benzene (organotelluranes RF-13R and RF-13S) were evaluated as inhibitors of cathepsins B and L, showing significant enantiodiscrimination. We observed their cytotoxic effects on a murine melanoma model, effectively inhibiting tumor progression in vivo. The enantiomers were able to inhibit melanoma cell viability, migration and invasion in vitro. Besides, RF-13S and RF-13R were able to inhibit endothelial cell angiogenesis using a tube formation assay in vitro, in a stereodependent manner. These organotelluranes affected cell morphology, showing disassembling of the actin cytoskeleton. These results suggest organotelluranes as potential antitumor agents, acting directly on tumor cell proliferation, migration and invasion, and on endothelial cells, disrupting angiogenesis, showing low toxicity and high efficiency. Taken together our results suggest that this class of compounds should be further studied to reveal their potential as antitumoral agents.

1-Butyl-1-chloro-3-methyl-3H-2,1λ4-benzoxa-tellurole: crystal structure and Hirshfeld analysis.

Two independent mol-ecules comprise the asymmetric unit in the title benzoxatellurole compound, C12H17ClOTe. The mol-ecules, with the same chirality at the methine C atom, are connected into a loosely associated dimer by Te⋯O inter-actions, leading to a {⋯Te-O}2 core. The resultant C2ClO2 donor set approximates a square pyramid with the lone pair of electrons projected to occupy a position trans to the n-butyl substituent. Inter-estingly, the TeIV atoms exhibit opposite chirality. The major difference between the independent mol-ecules relates to the conformation of the five-membered chelate rings, which is an envelope with the O atom being the flap, in one mol-ecule and is twisted about the O-C(methine) bond in the other. No directional inter-molecular inter-actions are noted in the mol-ecular packing beyond the aforementioned Te⋯O secondary bonding. The analysis of the Hirshfeld surface reveals the dominance of H⋯H contacts, i.e. contributing about 70% to the overall surface, and clearly differentiates the immediate crystalline environments of the two independent mol-ecules in terms of both H⋯H and H⋯Cl/Cl⋯H contacts.

Extension of raw watermelon juice shelf-life up to 58days by hyperbaric storage.

Hyperbaric storage (HS) of raw watermelon juice, at 50, 62.5 and 75MPa, at temperatures of 10, 15 and ≈25°C (room temperature, RT), was studied to evaluate shelf-life comparatively to refrigeration (RF, 4°C). Generally, RF caused an increase of microbial loads to values ≥6.0logCFU/mL after 7days of storage. Contrarily, HS at 62.5/75MPa (15°C) showed a reduction of initial loads, by at least 2.5logCFU/mL, up to 58days, while pH and colour values did not changed under these HS conditions. Additionally, the combination of a lower temperature with HS has beneficial effects to control microbial development, particularly for the lower pressure studied (50MPa/10°C). In conclusion, HS increased watermelon juice shelf-life for at least 58days, indicating a great potential for future RF replacement.

Marine Biodiversity in Juan Fernández and Desventuradas Islands, Chile: Global Endemism Hotspots.

The Juan Fernández and Desventuradas islands are among the few oceanic islands belonging to Chile. They possess a unique mix of tropical, subtropical, and temperate marine species, and although close to continental South America, elements of the biota have greater affinities with the central and south Pacific owing to the Humboldt Current, which creates a strong biogeographic barrier between these islands and the continent. The Juan Fernández Archipelago has ~700 people, with the major industry being the fishery for the endemic lobster, Jasus frontalis. The Desventuradas Islands are uninhabited except for a small Chilean military garrison on San Félix Island. We compared the marine biodiversity of these islands across multiple taxonomic groups. At San Ambrosio Island (SA), in Desventuradas, the laminarian kelp (Eisenia cokeri), which is limited to Desventuradas in Chile, accounted for >50% of the benthic cover at wave exposed areas, while more sheltered sites were dominated by sea urchin barrens. The benthos at Robinson Crusoe Island (RC), in the Juan Fernández Archipelago, comprised a diverse mix of macroalgae and invertebrates, a number of which are endemic to the region. The biomass of commercially targeted fishes was >2 times higher in remote sites around RC compared to sheltered locations closest to port, and overall biomass was 35% higher around SA compared to RC, likely reflecting fishing effects around RC. The number of endemic fish species was extremely high at both islands, with 87.5% of the species surveyed at RC and 72% at SA consisting of regional endemics. Remarkably, endemics accounted for 99% of the numerical abundance of fishes surveyed at RC and 96% at SA, which is the highest assemblage-level endemism known for any individual marine ecosystem on earth. Our results highlight the uniqueness and global significance of these biodiversity hotspots exposed to very different fishing pressures.

Determination of lead in biomass and products of the pyrolysis process by direct solid or liquid sample analysis using HR-CS GF AAS.

A method has been developed for the determination of lead in biomass, bio-oil, pyrolysis aqueous phase, and biomass ashes by high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GF AAS) and direct solid or liquid sample analysis. All measurements were performed without chemical modifier and calibration could be carried out using aqueous standard solutions. A pyrolysis temperature of 800°C and an atomization temperature of 2200°C were applied. The limits of detection and quantification were, respectively, 0.5 µg kg(-1) and 2 µg kg(-1) using the analytical line at 217.001 nm and 6 µg kg(-1) and 19 µg kg(-1) at 283.306 nm. The precision, expressed as relative standard deviation, was between 3% and 10%, which is suitable for direct analysis. The lead concentrations found for the solid samples varied between 0.28 and 1.4 mg kg(-1) for biomass and between 0.25 and 2.3 mg kg(-1) for ashes, these values were much higher than those found for bio-oil (2.2-16.8 µg kg(-1)) and pyrolysis aqueous phase (3.2-18.5 µg kg(-1)). After the determination of lead in the samples, it was possible to estimate the relative distribution of this element in the fractions of the pyrolysis products, and it was observed that most of the lead present in the biomass was eliminated to the environment during the pyrolysis process, with a significant portion retained in the ashes.

Long-lasting concentrations of cefovecin after subcutaneous and intramuscular administration to Patagonian sea lions (Otaria flavescens).

Cefovecin is a third-generation cephalosporin developed as an aqueous solution for use by the subcutaneous route in dogs and cats. This study evaluated the duration of cefovecin plasma concentrations after single intramuscular (IM) or subcutaneous (SC) injection at different doses in 10 Patagonian sea lions (Otaria flavescens). Blood samples were collected serially from the day of the injection up to 60-90 days post-injection. Plasma drug concentrations were determined by high performance liquid chromatography-UV detection and pharmacokinetic parameters were calculated by non-compartmental analysis. No reactions or side effects associated with the drug were observed in any of the studied animals. Both routes showed very similar pharmacokinetic behaviour. Elimination half-life (11.3-21.6 days, SC; 13.1-15.9 days, IM) and mean residence time (17.6-36.8 days SC; 16.5-25.4 days IM) were, in all cases and doses, considerably longer than those previously reported for any other species. Based on these findings, and preliminary data on specific pathogen sensitivity, cefovecin was found to be a very promising antimicrobial for Patagonian sea lions, in particular those that are difficult to access or that are under certain rehabilitation conditions.

Photochemical and Photophysical Properties of Phthalocyanines Modified with Optically Active Alcohols.

Three phthalocyanine derivatives were synthesized and characterized: one modified with a racemic mixture of 1-(4-bromophenyl)ethanol and two other macrocycles modified with each one of the enantioenriched isomers (R)-1-(4-bromophenyl)ethanol and (S)-1-(4-bromophenyl)ethanol. The compounds were characterized by 1H-NMR spectroscopy, mass spectrometry, UV-Vis absorption, and excitation and emission spectra. Additionally, partition coefficient values and the quantum yield of the generation of oxygen reactive species were determined. Interestingly, the phthalocyanine containing a (R)-1-(4-bromophenyl)ethoxy moiety showed higher quantum yield of reactive oxygen species generation than other compounds under the same conditions. In addition, the obtained fluorescence microscopy and cell viability results have shown that these phthalocyanines have different interactions with mammary MCF-7 cells. Therefore, our results indicate that the photochemical and biological properties of phthalocyanines with chiral ligands should be evaluated separately for each enantiomeric species.

Biocatalysis for desymmetrization and resolution of stereocenters beyond the reactive center: How far is far enough?

The kinetic resolution of racemates and desymmetrization are the most common approaches to the preparation of enantiomerically enriched compounds. These procedures allow the access of high valuable, chiral building blocks for many purposes in academic or industrial R&D endeavors. Nevertheless, the scope of stereochemistry recognition in biotransformations usually occurs at the site of the transformation or when it is close to it (not more than 3 bonds). However, there are a growing number of enzymatic transformations which surpass the limits of stereorecognition of remote chiral (or prochiral) centers. In this account, we would like to present some aspects of biocatalyzed remote resolutions and remote desymmetrizations to call attention for these challenging transformations.