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The total synthesis of darobactin A, a recently isolated antibiotic that selectively targets Gram-negative bacteria, has been accomplished in a convergent fashion with a longest linear sequence of 16 steps from ᴅ-Garner’s aldehyde and ʟ-serine. Scalable routes towards three non-canonical amino acids were developed to enable the synthesis. The closure of the bismacrocycle was realized through sequential, halogen-selective Larock indole syntheses, where the proper order of cyclizations proved crucial for the formation of the desired atropisomer of the natural product.

Recent advances in the field of cancer biology have accelerated the discovery and development of novel biopharmaceuticals. At the forefront of these drug development efforts are high-throughput screening, compressed timelines, and limited sample quantities, all characteristic of the discovery space. To meet program targets, large numbers of protein variants must be produced, screened, and characterized, presenting a daunting analytical challenge. Additionally, the higher-order structure is paramount for protein function and must be monitored as a critical quality attribute. Matrix-assisted laser desorption/ionization mass spectrometry has been utilized as an ultra-fast, automatable, sample-sparing analytical tool for biomolecules. Our group has published applications integrating hydrogen-deuterium exchange mass spectrometry with matrix-assisted laser desorption/ionization mass spectrometry for the rapid conformational characterization of small proteins, the current work expands this application to monoclonal and bi-specific antibodies. This study demonstrates the ability of the methodology, matrix-assisted laser desorption/ionization hydrogen-deuterium exchange mass spectrometry, to detect conformational differences between bi-specific antibodies from different expression hosts. These conformational differences were validated by orthogonal techniques including circular dichroism, nuclear magnetic resonance, and size-exclusion chromatography hydrogen-deuterium exchange mass spectrometry. This work demonstrates the utility of applying the developed methodology as a rapid conformational screening tool to triage samples for further analytical characterization.

El texto analiza el modelo de protección de datos personales ante la ausencia de una autoridad de control. Se examina cómo se protegen los datos personales en sector público y en el sector privado. El artículo concluye que, a pesar de la inexistencia de una autoridad de control especializada, la garantía del derecho se da a través de competencias fragmentadas y sectoriales, en función de la agenda de cada entidad pública.

La producción equina tiene particularidades que dificultan su interpretación y análisis con los modelos industriales o agropecuarios tradicionales. La modelación en base económica o de resultados en las asignaturas productivas resulta esencial para manejar el enfoque, más aún en alumnos con fuerte formación clínica. En este trabajo presentamos una herramienta versátil de análisis, enfocada principalmente al veterinario zootecnista, de manera que éste a través de un pequeño formulario, encuentre los puntos principales a trabajar en el establecimiento, con el énfasis en poder proyectar mejoras y generar un negocio rentable, o que se auto sustente. Se propone análisis fragmentado y ponderado del sistema. Para lo cual dividimos para el análisis al establecimiento en 3 sectores: estructura no animal, manejo de animales y gestión económica. Esta herramienta se utiliza en la materia producción equina de la FCV-UNLP en las últimas 3 semanas de cursada integrando los conocimientos desarrollados en el cuatrimestre, trabajando en este caso con situaciones reales y ficticias desarrolladas por los docentes a modo de visualizar los problemas más frecuentemente encontrados en nuestro medio. Consideramos un aporte significativo en el marco docente y práctico para el perfil del veterinario zootecnista equino a partir del elemento de análisis aquí desarrollado., Equine production has particularities that make it difficult to interpret and analyze with traditional industrial or agricultural models. Modeling based on economics or results in productive subjects is essential to manage the approach, even more so in students with strong clinical training.In this paper we present a versatile analysis tool, focused mainly on the veterinary zootechnician, so that through a small form, find the main points to work on in the establishment, with the emphasis on being able to project improvements and generate a profitable business, or that is self-sustaining. Fragmented and weighted analysis of the system is proposed. For which we divide the establishment into 3 sectors: non-animal structure, animal management and economic management. This tool is used in the equine production subject of the FCV-UNLP in the last 3 weeks of the course integrating the knowledge developed in the semester, working in this case with real and fictitious situations developed by teachers in order to visualize the problems most frequently encountered in our environment.We consider a significant contribution in the teaching and practical framework for the profile of the equine veterinary zootechnician from the element of analysis developed here., Especialización en Docencia Universitaria, Facultad de Ciencias Veterinarias

El texto examina la inclusión del interés legítimo en la reforma a la legislación sobre protección de datos personales en Chile. Primero, describe los elementos básicos del interés legítimo como base de licitud para el tratamiento de datos personales. Luego, revisa cómo el proyecto de ley que reforma la Ley 19.628, Sobre Protección de la Vida Privada, busca incluir el interés legítimo. A partir de ello, se analizan cuatros factores relevantes que deben ser atendidos en la reforma de la ley, con el objeto de converger con los estándares internacionales en materia de interés legítimo. El texto concluye con recomendaciones para la regulación del interés legítimo en la tramitación legislativa de la reforma a la Ley 19.628.

Tightly regulated activity of the transcription factor MYC is essential for orderly cell proliferation. Upon deregulation, MYC elicits and promotes cancer progression. Proteasomal degradation is an essential element of MYC regulation, initiated by phosphorylation at Serine62 (Ser62) of the MB1 region. Here, we found that Ser62 phosphorylation peaks in mitosis, but that a fraction of nonphosphorylated MYC binds to the microtubules of the mitotic spindle. Consequently, the microtubule-destabilizing drug vincristine decreases wild-type MYC stability, whereas phosphorylation-deficient MYC is more stable, contributing to vincristine resistance and induction of polyploidy. PI3K inhibition attenuates postmitotic MYC formation and augments the cytotoxic effect of vincristine. Implications: The spindle's function as a docking site for MYC during mitosis may constitute a window of specific vulnerability to be exploited for cancer treatment.

Understanding the dissociation of molecules is the basis to modulate interactions of biomedical interest. Optimizing drugs for dissociation rates is found to be important for their efficacy, selectivity, and safety. Here, we show an application of the high-power relaxation dispersion (RD) method to the determination of the dissociation rates of weak binding ligands from receptors. The experiment probes proton RD on the ligand and, therefore, avoids the need for any isotopic labeling. The large ligand excess eases the detection significantly. Importantly, the use of large spin-lock fields allows the detection of faster dissociation rates than other relaxation approaches. Moreover, this experimental approach allows to access directly the off-rate of the binding process without the need for analyzing a series of samples with increasing ligand saturation. The validity of the method is shown with small molecule interactions using two macromolecules, bovine serum albumin and tubulin heterodimers.

Human guanylate kinase (hGMPK) is a critical enzyme that, in addition to phosphorylating its physiological substrate (d)GMP, catalyzes the second phosphorylation step in the conversion of anti-viral and anti-cancer nucleoside analogs to their corresponding active nucleoside analog triphosphates. Until now, a high-resolution structure of hGMPK is unavailable and thus, we studied free hGMPK by NMR and assigned the chemical shift resonances of backbone and side chain 1H, 13C, and 15N nuclei as a first step towards the enzyme’s structural and mechanistic analysis with atomic resolution.

Horses kept in stables may exhibit undesirable behaviours and stress during police service. The objective of this study was to evaluate the influence of confinement, i.e., time in stalls, on horse behaviour and welfare employed by mounted patrols in urban areas. Eight adult horses were subjected to one of two types of confinement during 16 days, namely: total confinement (TC – 24 h in a stall) and partial confinement (PC – 12 h in a stall and 12 h free in a paddock); then the treatments were reversed. Mounted patrols were conducted in pairs, with one animal from each treatment group, for six hours every other day in a scheme of five 40-min rides interspersed with four 20-min rest periods. Animal behaviour was evaluated by applying direct coded focal observations (SA – standing alert, SC – standing calm, M – movement, EF – eating forage, DW – drinking water, V – vocalizing, SI – positive or negative social interactions, S – stereotypies, and O – others) for three time periods on non-work days, and during rest periods of the last patrol day for each experimental stage. Behaviours were assessed through a questionnaire (A – alert, C – curious, D – distracted, Dr – drowsy, SI – socially interactive, F – fearful, and N – nervous), by the military personnel during patrols. Heart rate (HR), HR variability (SDNN, VLF, LF, HF, and LF/HF), blood count, and cortisol levels were determined on the first and last non-work day and on the first, third, and seventh day of patrolling. The experiment was performed under a randomized block design, and the data were compared by Tukey’s test using SAS statistical software (P

The dynamic nature of FRET sensor Twitch-2B, as probed by x-ray, NMR, and modeling, reveals key information on how to tune FRET., Förster resonance energy transfer (FRET) between mutants of green fluorescent protein is widely used to monitor protein-protein interactions and as a readout mode in fluorescent biosensors. Despite the fundamental importance of distance and molecular angles of fluorophores to each other, structural details on fluorescent protein FRET have been missing. Here, we report the high-resolution x-ray structure of the fluorescent proteins mCerulean3 and cpVenus within the biosensor Twitch-2B, as they undergo FRET and characterize the dynamics of this biosensor with B02-dependent paramagnetic nuclear magnetic resonance at 900 MHz and 1.1 GHz. These structural data provide the unprecedented opportunity to calculate FRET from the x-ray structure and to compare it to experimental data in solution. We find that interdomain dynamics limits the FRET effect and show that a rigidification of the sensor further enhances FRET.

Human guanylate kinase (hGMPK) is the only known enzyme responsible for cellular GDP production, making it essential for cellular viability and proliferation. Moreover, hGMPK has been assigned a critical role in metabolic activation of antiviral and antineoplastic nucleoside-analog prodrugs. Given that hGMPK is indispensable for producing the nucleotide building blocks of DNA, RNA, and cGMP and that cancer cells possess elevated GTP levels, it is surprising that a detailed structural and functional characterization of hGMPK is lacking. Here, we present the first high-resolution structure of hGMPK in the apo form, determined with NMR spectroscopy. The structure revealed that hGMPK consists of three distinct regions designated as the LID, GMP-binding (GMP-BD), and CORE domains and is in an open configuration that is nucleotide binding–competent. We also demonstrate that nonsynonymous single-nucleotide variants (nsSNVs) of the hGMPK CORE domain distant from the nucleotide-binding site of this domain modulate enzymatic activity without significantly affecting hGMPK's structure. Finally, we show that knocking down the hGMPK gene in lung adenocarcinoma cell lines decreases cellular viability, proliferation, and clonogenic potential while not altering the proliferation of immortalized, noncancerous human peripheral airway cells. Taken together, our results provide an important step toward establishing hGMPK as a potential biomolecular target, from both an orthosteric (ligand-binding sites) and allosteric (location of CORE domain-located nsSNVs) standpoint.

The article examines the concept of legitimate interest as a lawful basis for processing personal data. First, the concept of legitimate interest and its connection with the principle of lawfulness of processing personal data is developed. Second, the text examines the European and Spanish sources of the concept of legitimate interest. Finally, it analyzes the status of legitimate interest in Chilean legislation, both under Law 19.628, On the Protection of Privacy, and in banking legislation. The paper concludes that the concept of legitimate interest has been adequately developed in comparative law and that, in the event of amending Law 19.628, such standards should be considered in their general reception under Chilean law. © 2019 Universidad de Chile. All rights reserved.

Startle is a fast response elicited by sudden acoustic, tactile or visual stimuli in a variety of animal species and in humans. The magnitude of startle response can be modulated by external and internal variables and can be a useful tool to study the sensory-motor integration in animals. Different stimuli have been used to induce startle in horses, which makes it difficult to compare the responses to these different approaches. The present study uses ultra-short-term heart rate variability (HRV) analysis to characterize the cardiac autonomic modulation, reactivity assessment and blood cortisol measurements to describe the behavioural and endocrine responses to a simple, easy to replicate, effective and safe method of startle (an umbrella is abruptly opened near the horse). The ultra-short-term (64 s) heart rate (HR) series were interpolated (4 Hz) and divided into 256 points segments then the spectra calculated (Fast Fourier Transform). The spectra were then integrated into low (LF; 0.01–0.07 Hz; Index of Cardiac Sympathetic Modulation) and high (HF; 0.07–0.50 Hz; Index of Cardiac Parasympathetic Modulation) frequency bands. Following the startle test, the HR (p = 0.0101), the power of the LF band of the cardiac interval spectrum (p = 0.0002) and the LF/HF ratio (p = 0.0066) were found to be higher, whereas the power of the HF band of the cardiac interval spectrum was found to be lower (p = 0.0002). Also, the horses showed a noticeable escape response, with latency of reaction varying from 0.28 to 1.28 s, duration of reaction ranging from 1.52 to 7.92 s and escape distance covered varying from 3.43 to 9.97 m. However, the endocrine measurements failed to reveal significant changes in the cortisol levels after the startle test. We conclude that the startle test used in the current study was effective to produce changes in behavioural parameters and cardiac autonomic modulation of the horses and can therefore be an appropriate tool for neurobiological studies. Furthermore, the use of ultra-short segments (64 s) for HRV analysis appears to be effective and promising for the detection of mental stress in horses., Instituto de Genética Veterinaria

The Argentine Polo Horse (AP), an autochthonous breed officially created in Argentina in the early 1980s, is globally recognized as the best equid for playing polo. Their breeding is characterized by the use of cutting-edge assisted reproductive techniques such as large-scale embryo transfer (ET) programs and cloning. The aim of this study was to determine the impact of the use of those reproductive biotechnologies on the genetic structure, variability and reproductive parameters of the AP breed using genealogical data (81,633 pedigree records). In total, 18,077 animals drawn from the last generation (2006–2015) were employed as the reference population (WP), which was further divided into two subsets: animals produced (ET; n = 13,478) and not produced by ET (NOT-ET; n = 4,599). Horses produced by ET showed a significant decrease in generation interval compared with NOT-ET. On the other hand, the number of foals per stallion and broodmare as well as inbreeding (F = 0.89%) and average relatedness (AR=1%) were higher in ET compared with NOT-ET (F = 0.6%; AR = 0.54%), depicting an increased selective intensity. Our analysis also revealed that the effective number of founders and ancestors in ET showed a disproportionate gene contribution and a strong genetic bottleneck as well as the inter-herd fixation index (FST) revealed an increased genetic flow among herds and higher internal relatedness values within ET horses. In conclusion, the use of large-scale ET programs decreased genetic variability (lower effective population size and number of founders and ancestors and higher F, AR and coancestry), increased the genetic flow among herds and decreased the generation interval, contributing to the possibility of higher rates of genetic progress in the AP.

The objective of this work was to evaluate the effects of equine infectious anemia (EIA) on the physical performance of equines from the Brazilian Pantanal region. A total of 16 males were evaluated, divided into two groups: 8 seronegative (G1) and 8 seropositive (G2) for EIA. Two graded exercise tests were carried out before (T1) and after (T2) 42 days of training. Heart rate, lactate concentration, distance covered, and hematocrit level were recorded. In both tests, G1 covered a greater distance. In T2, G2 had lower hematocrit levels and lower speeds reached at different lactate concentrations and heart rates. The athletic performance of the evaluated equines is affected by equine infectious anemia., O objetivo deste trabalho foi avaliar o efeito da anemia infecciosa equina (AIE) no desempenho físico de equinos da região do Pantanal brasileiro. Foram avaliados 16 machos, divididos em dois grupos: 8 soronegativos (G1) e 8 soropositivos (G2) para AIE. Dois testes de esforço progressivo foram realizados, antes (T1) e após (T2) 42 dias de treinamento. Foram registrados frequência cardíaca, concentração de lactato, distância percorrida e níveis de hematócrito. Em ambos os testes, o G1 percorreu uma distância maior. No T2, o G2 apresentou menores níveis de hematócrito e menor velocidade obtida a diferentes concentrações de lactato e frequências cardíacas. O desempenho atlético dos equídeos avaliados é afetado pela anemia infecciosa equina., Instituto de Genética Veterinaria

This study aimed to assess the physical performance of Pantaneiro horses with and without equine infectious anemia (EIA) under functional conditions of cattle management. The horses were subjected to a performance test and split into two groups according to a completely randomized design: animals were chosen from populations testing positive and negative for EIA. Performance was measured as a function of a data envelopment analysis (DEA) model considering four outputs and one unitary input. The output measures were the distance achieved in the performance test, hematocrit as a weighted average over the test duration, respiratory rate as weighted average over the test duration, and the level of lactic acid at the test termination. Weights for the hematocrit and the respiratory rate output variables were determined by means of factor analysis. The performance score was a weighted average of the output variables with the weights defined by the averages of the optimum individual multipliers in the DEA analysis. Contextual variables of interest were age, horse weight, room temperature, and corporal temperature. Only groups and room temperature were statistically significant effects, as indicated by a bootstrap analysis. The performance of group positive for EIA is significantly lower than that of the group negative for EIA and room temperature has a negative effect., Instituto de Genética Veterinaria

A 10-year-old endurance horse was presented because of tiredness in training, inability to finish the races, and colic in competition. The horse was continuously supplemented with four different hematinic compounds for more than 8months. Physical examination showed mild hyperemia, and blood analysis revealed erythrocytosis, increased γ-glutamyl transferase (GGT), and bilirubin with normal total solids (TS) and albumin. Arterial blood gas analysis and ultrasonography were irrelevant. Serum testosterone was within reference range, and increased serum erythropoietin and cobalamin were found. The horse was subjected to a treadmill endurance exercise and after 20minutes of exercise, blood had a sticky and dark appearance. Exercise was stopped because the horse presented an episode of colic. Packed cell volume (PCV) of 58% and TS of 6.1g/dL were found at that moment. An inappropriate secondary erythrocytosis because of supplementation was diagnosed. Supplementation was suspended and in the reevaluation 3 months later, PCV reached 49% after 20minutes of exercise. Bilirubin, GGT, erythropoietin, and cobalamin values were normalized. Seven months later, resting PCV was 36%, and the horse was competing successfully in longer distances. It is concluded that erythrocytosis in an endurance horse might have detrimental effects on performance. Fil: Muñoz, Ana. Universidad de Córdoba; España Fil: Roldán, Juan. Universidad de Córdoba; España Fil: Trigo, Pablo Ignacio. Universidad de Córdoba; España. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gómez Díez, Manuel. Universidad de Córdoba; España Fil: Satué, Katy. Universidad de Córdoba; España Fil: Castejón Riber, Cristina. Universidad de Córdoba; España

The objective of this study was to assess the effects of supplementation with Saccharomyces cerevisiae on the performance of Mangalarga Marchador equines and to verify the effectiveness of the aerobic training protocol adopted. The study used 14 Mangalarga Marchador mares in a completely randomized split-plot design. The plots were made up of two treatments (groups Probiotic and Control) and the split plots comprised two maximal-effort physical tests applied both before and after the six weeks of training. The animals’ spirometric parameters, heart rate, and plasma lactate levels were assessed. No difference was found between the Probiotic and Control groups in any of the parameters assessed. A difference was found in the physical tests for time-to-fatigue, aerobic and anaerobic thresholds, speed at which plasma lactate levels reached 2 and 4 mmol/L, speed at which the heart rate reached 200 bpm, and the lactate level at 30 min of the recovery period. Supplementation with Saccharomyces cerevisiae has no effect on physical conditioning of Mangalarga Marchador mares and the aerobic training protocol adopted increases the animals’ aerobic and anaerobic capacity., Instituto de Genética Veterinaria

The Mangalarga Marchador breed is functionally evaluated through marcha contests. The present research aimed to verify the efficacy of a training protocol for conditioning Mangalarga Marchador horses for marcha contests. Eight mares were used in a completely randomized block split-plot design, where each animal was a block, the physical tests (T I, T II, T III, T IV and T V) every 21 days of training were the plots, and the time of evaluation and collection of samples inside each test were the split-plots. The mares were trained for 84 days for one hour a day, five days a week, with rest on Saturdays and Sundays. On Mondays, Wednesdays, and Fridays, the animals warmed up in an oval track by walking for 10 minutes and then marching for a period established individually through a marcha test. Next, the animals were led in walk gait until an hour of exercise was completed. On Tuesdays and Thursdays, the animals were trained outdoors for one hour only walking. The tests consisted of successive 10 minutes stages at marcha, which was interrupted when heart rate reached 150 beats per minute and lactate levels were greater than 4 mmol/L, or after 70 min of the test. Marcha duration, heart rate and blood concentrations of lactate were evaluated. The results were submitted to an analysis of variance and the averages were compared by Fisher’s test at 5% probability. From zero at nine weeks of training, marcha duration increased progressively (p < 0.05), but there was no difference (p >0.05) between nine and 12 weeks of training. The training protocol used was appropriate to condition Mangalarga Marchador equines to compete in marcha contests following the rules of Brazilian Association of Mangalarga Marchador Breeders. A raça Mangalarga Marchador é avaliada funcionalmente através das provas de marcha. O presente estudo objetivou verificar a eficácia de um protocolo de treinamento para condicionar equinos Mangalarga Marchador visando participação em provas de marcha. Foram utilizadas oito éguas em delineamento de blocos ao acaso com esquema de parcelas subdivididas, onde cada animal constituiu um bloco, as parcelas foram representadas pelos testes físicos (T I, T II, T III, T IV e T V) realizados a cada 21 dias do treinamento e as subparcelas foram constituídas pelos tempos de avaliação e coletas de amostras em cada teste. As éguas foram treinadas durante 84 dias, uma hora por dia, cinco dias por semana, com descanso aos sábados e domingos. Nas segundas, quartas e sextas-feiras, os animais realizavam 10 minutos de aquecimento ao passo em uma pista oval, em seguida marchavam por um tempo individual de marcha, estabelecido em um teste prévio. Depois, caminhavam até completar uma hora de exercício. Na terças e quintas-feiras eram montadas ao passo por uma hora. Os testes foram formados por etapas sucessivas de 10 minutos de marcha, sendo interrompido quando a frequência cardíaca atingia 150 batimentos por minuto e a concentração de lactato era maior que 4mmol/L ou a prova atingisse 70 minutos de duração. Avaliou-se o tempo de marcha, frequência cardíaca e concentração sanguínea de lactato. Os resultados foram submetidos à análise de variância e as médias comparadas pelo teste de Fisher a 5% de probabilidade. De zero a nove semanas de treinamento, o tempo de marcha aumentou progressivamente (p < 0,05), mas não houve diferença (p > 0,05) entre nove e doze semanas de treinamento. O protocolo de treinamento adotado foi adequado para condicionar equinos Mangalarga Marchador para competir em uma prova de marcha realizada de acordo com a regulamentação da Associação Brasileira de Criadores do Cavalo Mangalarga Marchador. Fil: Abrantes, Renata Guimarães Pequeno. Universidade Federal do Minas Gerais; Brasil Fil: Rezende, Adalgiza Souza Carneiro de . Universidade Federal do Minas Gerais; Brasil Fil: Santiago, Juliano Martins. Universidade Federal Rural Pernambuco; Brasil Fil: Trigo, Pablo Ignacio. Universidade Federal Rural do Rio de Janeiro; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Melo, Marília Martins. Universidade Federal do Minas Gerais; Brasil Fil: Fonseca, Mayara Gonçalves. Universidade Federal do Minas Gerais; Brasil Fil: Lage, Jéssica. Universidade Federal do Minas Gerais; Brasil Fil: Moreira, Dalton Colares de Araújo. Universidade Federal do Minas Gerais; Brasil

This study was designed to evaluate changes on variables in blood, urine and water balance in horses in response to a single dose of electrolyte supplementation. The essay was conducted on a randomised 3×3 Latin Square design repeated over time, with three animals and three treatments: Treatment 1: control group (without supplementation); Treatment 2: supplementation with a medium dose of electrolytes composed of: 0.25 g of NaCl + 0.125 g of KCl + 0.05 g of CaCl + 0.025 g of MgCl per kg of BW; Treatment 3: supplementation with a high dose of electrolytes composed of: 0.625 g of NaCl + 0.3125 g of KCl + 0.125 g of CaCl + 0.0625 g of MgCl per kg of BW, equivalent to 2.5 times the medium dose of supplementation. The electrolytes were supplied through a nasogastric tube 4 h after the morning meal. The diet provided had a forage:concentrate ratio of 70:30, composed of coastcross hay and commercial concentrate, with an estimated consumption of 2% of body weigth (BW). Horses received 116 mg/kg of BW of commercial mineral salt mixed in the concentrate. Samples of blood, urine and digesta were collected over a 12 h period after supplementation for analysis of sodium, potassium, chloride, calcium and magnesium concentration. Water intake and urine output were also measured. Electrolytic supplementation enhanced (P0.05). The supplementation also influenced the sodium and chloride excretion in urine (P

Deuterium NMR imaging was used to evaluate the spatial distribution of the degree of alignment in different types of alignment media by monitoring the deuterium quadrupolar splitting using spatially resolved NMR techniques in conventional liquid state NMR instruments. These images allow the unambiguous distinction of magnetic field and alignment inhomogeneities present in partially aligned samples, revealing the underlying reasons for linebroadening within an alignment medium that cannot be explained by the sole analysis of 1D (2)H NMR spectra. For example, alignment inhomogeneities due to broken gels or the presence of concentration gradients in liquid crystalline solutions are clearly detected by the imaging methods proposed in this work.

The dependence of molecular alignment with solvent nature and salt concentration has been investigated for mechanically stretched polyacrylamide copolymer gels. Residual dipolar couplings (RDCs) were recorded for D(2)O, DMSO-d(6), and DMSO-d(6)/D(2)O solutions containing different proportions of the solvents and different sodium chloride concentrations. Alignment tensors were determined by fitting the experimental RDCs to the DFT-computed structure of N-methylcodeinium ion. Analysis of the tensors shows that the degree of alignment decreases with the proportion of DMSO-d(6) as well as with the concentration of sodium chloride, most likely due to enhanced ion-pair aggregation. Furthermore, rotation of the alignment tensor is observed when increasing the salt concentration.

Equine neonatal septicemia could lead to the release of thrombus and heart valvular endocarditis. A relationship between activation of the renin-angiotensin-aldosterone-vasopressin (RAAV) axis and heart failure has been described in several species. This article describes the echocardiographic, electrocardiographic, and laboratory findings, including RAAV axis, in two Spanish foals with endocarditis after septicemia in comparison with two control groups matched by age and gender. Two Spanish foals (F1, 60-day-old colt; F2, 76-day-old filly) were presented with poor growth rate a month after being hospitalized because of septicemia. Colt F1 had hypercortisolemia and increased left ventricular internal dimensions in systole and diastole, increased left ventricular free wall thickness in diastole, interventricular septum thickness in diastole, and mitral valve thickness. Colt F1 also presented lower fractional shortening, ejection fraction, fractional wall thickness, and fractional septum thickness. Filly F2 showed hyperfibrinogenemia and increased values for aspartate aminotransferase, lactate dehydrogenase, creatin kinase, alkaline phosphatase, interventricular septum at systole, aorta diameter at the level of valve leaflets and sinotubular junction, and mitral and tricuspid valve thickness. The foals did not present systemic signs compatible with heart failure, heart arrhythmias were not found, and RAAV values were within the expected confidence limits. In conclusion, endocarditis without clinical signs of heart failure can appear shortly after septicemia in equine neonates. The measurement of the thickness of the valves by two-dimensional echocardiography is diagnostic. The lack of activation of RAAV in both foals might indicate that the severity of the heart problem was mild.

Show jumping is a century-old Olympic sport performed worldwide. However, despite the prominence of this sport, there is currently no satisfactory evaluation of the physical fitness of its horses. Our study compared two standardised exercise tests (specific and nonspecific for show jumpers) to determine the importance of a show jumping specific evaluation test. Sixteen horses were divided into two performance groups (high and low performance), and all horses performed standardised exercise tests without jumps (SET1) and with jumps (SET2). Heart rate, blood lactate, glucose, blood gas, haematological parameters, and plasma ions were measured before and after the tests, and performance indices were calculated. Both exercise tests (SET1 and SET2) resulted in changes in nearly all measured variables that were expected, based on other studies, for the duration and nature of the exercise performed. Differences between the two performance groups were observed for lactate and glucose, as well as some blood gas variables and performance indicators. These differences might have been the result of better cardiovascular and metabolic adaptation of the high performance group to the show jumping exercises. For the SET1, differences between groups were mainly noted for variables related to aerobic capacity, which suggests that this measurement is important for the evaluation of equine performance in show jumping. The SET2 was capable of detecting different horse performance levels that could not be detected by the SET1, which indicates that a specific test for show jumping (that includes jumping movements) could provide important information for the evaluation of show jumpers. Based on our findings, we recommend that the SET2 be included in future protocols for evaluating jumping horses Fil: Soares, O.A.B.. Universidade de Sao Paulo; Brasil. Agulhas Negras Military Academy; Brasil Fil: Ferraz, G.C.. Universidade de Sao Paulo; Brasil Fil: Trigo, Pablo Ignacio. Universidad Nacional de La Plata; Argentina Fil: D'Angelis, F.H.F.. Universidade de Sao Paulo; Brasil Fil: Feringer Júnior, W.H.. Universidade de Sao Paulo; Brasil Fil: Nardi, K.B.. Universidade de Sao Paulo; Brasil Fil: Almeida, F.Q.. Universidade Federal do Rio de Janeiro; Brasil Fil: Queiroz Neto, A.. Universidade de Sao Paulo; Brasil

In order to assess which laboratorial parameters need specific age- and/or gender-related reference values, hematological and biochemical profiles (including hormones) were performed in 205 Spanish foals of 5 groups: A (1-2 months; 20 fillies, 10 colts), B (2-3 months; 24 fillies, 18 colts), C (3-6 months; 25 fillies, 16 colts), D (6-9 months; 20 fillies, 23 colts) and E (9-12 months; 25 fillies, 15 colts). Additionally, 120 adult horses were sampled in order to establish baseline data for this breed in our laboratory. Group E had lower red blood cell number and mean cell volume than B, C and D, and neutrophil count was lower in A. Albumin was lower in A than in D, lactate was higher in B, C and D, CK, AST and K were higher in C. In D and E, cortisol was lower and adrenaline was higher. Urea progressively increases, whereas ALP decreases with age. Packed cell volume was higher in fillies of group A, creatinine was higher in colts of group E and fillies of groups B, C, and D had higher aldosterone than colts. In comparison to Spanish adult horses, mean cell volume, albumin, urea, CK, AST, LDH, and ALP requires specific ranges for foals.

This research analyses the yeast supplementation effect on the digestibility of nutrients and metabolic performance in training horses. Twelve horses were assigned into 2 groups: Pr (20 g of probiotics daily per horse) and control. The diet consisted of roughage (haylage) and commercial rations and all horses were trained for 6 weeks. LIPE® indicator was used during 7 days and feces collected for five days to determine nutrient digestibility. DM, CP, DE, P, NDF, ADF, HCEL and lignin were determined. All horses were subjected to incremental ergospirometry test before and at the end of training. Horses that received live yeast showed an increase (p

Significant differences exist in the respiratory adaptation to exercise in different equine breeds. This research describes the ergoespirometric response to exercise of Andalusian (AN) and Arabian (A) horses, both selected according to morphological criteria. Thirteen untrained male horses (6 AN and 7 A) performed a treadmill exercise test (TET) with a slope of 6%, with workloads starting from 5 m/s and increasing 1 m/s every 3 min until the horses were not able to keep the required velocity. Tidal volume (TV), respiratory rate, minute ventilation (VE), oxygen uptake (VO2), carbon dioxide production, peak oxygen uptake (VO2peak), respiratory exchange ratio (RER), exercise time to fatigue (ETF) and respiratory aerobic threshold (RAT) were determined. AN horses presented higher TV and VE, whereas respiratory rate, VO2 and VCO2 were lower at the same velocities. RER was similar between breeds. ETF was longer in A horses (556.7 ± 66.5 in AN vs. 607.1 ± 71.1 s in A) and no significant differences were found in RAT (5.50 ± 0.50 in AN vs. 5.86 ± 1.07 m/s in A). In summary, despite the more intense ventilatory response to exercise at the same velocity, AN horses had lower VO2. The AN horse develops a more intense ventilatory response to fixed velocities than the A horse and it could be interesting to clarify the role of the locomotion characteristics in this response.

Accurate measurement of long-range CH residual dipolar couplings (RDCs) (2DCH and 3DCH) by a new selective J-scaled HSQC experiment significantly improves the structural discrimination power of RDCs in small molecules with multiple stereocenters. The extraction of the long-range couplings is clean and straightforward, and in most cases yields the sign of the RDC too. The experiment is demonstrated with 10-epi-8-deoxycumambrin B, a tricyclic natural compound with five chiral centers.

This study investigated the effect of hypertonic dehydration on exercise in horses. Valencian draft horses (n=43) with hypertonic dehydration following water and food deprivation and competing in pulling events (COM), were compared to euhydrated horses (n=11) during a pulling exercise test (PET). Both groups were divided into bodyweight (BW) categories A (≤350 kg), B (351-450 kg), and C (≥451 kg), and pulled 2, 2.25, and 2.5 times BW, respectively. Exercise duration (ED) was 1.3±0.8 min. Heart rate, respiratory rate, rectal temperature and blood samples were taken at rest, after exercise, and during the first 30 min of passive recuperation. The only difference between BW categories was the packed cell volume (PCV), which was higher after exercise in COM horses in group A (52.7±2.3%) than in B (49.3±3.4%), so the data for the three BW categories were combined. The COM horses had higher levels of resting plasma proteins, albumin, urea, creatinine, sodium and arginine vasopressin (AVP) than PET horses. Exercise induced significantly greater (P0.05) increases in heart rate and lactate in the COM horses. AVP was negatively correlated with ED and positively with PCV, plasma proteins, albumin, urea, and sodium. Peak AVP concentrations did not differ in the two groups.

Growth rate, tissue repair and reproductive functions are mediated by the somatotrophic axis, the growth hormone (GH) being one of its main components. GH is released in a pulsatile manner and a single measurement does not provide accurate information on the activity of the somatotrophic axis. The actions of GH on tissues are mediated by insulin-like growth factor type 1 (IGF-1), mainly released by the liver, and thus, the measurement of IGF-1 could be considered a good indicator of the activity of GH and the somatotrophic axis. Serum IGF-1 concentrations are relatively stable due to its long biological half-life without obvious diurnal rhythm. Additionally, many diseases significantly alter circulating IGF-1 concentrations, leading to potential diagnostic and prognostic uses in veterinary medicine. However, serum IGF-1 concentrations are affected by many factors, such as breed, age and sex. The present study analyzes the influence of these factors on serum IGF-1 concentra - tions in a population of 255 Andalusian horses (141 females and 114 males), divided into age groups: 1-2, 2-3, 3-4, 4-5, 5-6 and 6-12 months and 1-2, 2-4, 4-6, 6-10 and 10-14 years. The animals belonged to six different farms located in the same geographic location and were subjected to similar feeding and management protocols. Two measurements of body size were made: height at the withers (HW) and diameter of the thorax (DTx). Blood samples were taken always in the morning, in the month of July and serum IGF-1 concentrations were measured with a sandwich ELISA after dissociation of IGF-1 from its binding proteins. It was found that age and sex signifi - cantly influenced serum IGF-1 concentrations, whereas the effects of the farm and the time of blood withdrawal were not significant. Mean serum concentrations for both males and females respectively were: 246.3 and 231.0 (1-2 months), 201.9 and 194.7 (2-3 months), 174.2 and 170.4 (3-4 months), 161.7 and 155.4 (4-5 months), 166.1 and 136.9 (5-6 months), 127.2-114.5 (6-12 months), 103.3 and 89.01 (1-2 years), 104.3 and 73.41 (2-4 years), 105.4 and 64.40 (4-6 years), 53.29 and 68.27 (6-10 years) and 59.56 and 65.53 ng/ml (10-14 years). A progressive decrease in serum IGF-1 concentrations with increased age was found for both sexes. Males aged between five and 12 months and between two and six years had significantly higher serum IGF-1 concentrations than females of the same age. Coefficients of correlation between the indicators of body size (HW and DTx) and IGF-1 were -0.800 and -0.690 for the whole population of Andalusian horses, -0.860 and -0.750 for the males and -0.740 and -630 for the females. It is concluded that serum IGF-1 concentrations in Andalusian horses are reduced with ageing, male horses of determined age groups had higher IGF-1 than the females and there are negative correla - tions between body size and IGF-1 concentrations. The knowledge of the normal serum IGF-1 concentrations will help us to understand the role of the somatotrophic axis in several diseases and physiological situations and will provide information for further research on this equine breed.

Summary Reasons for performing study: Endurance races are the competition with the biggest metabolic demands for the sport horse. During races, some horses show homeostasis alterations, having repercussions in diverse biochemical parameters and negative consequences on performance and health. Objectives: To evaluate the utility of biochemical analysis in the early diagnosis of metabolic stress and to determine cut-off values of biochemical parameters to assist in the prevention of metabolic alterations in endurance horses. Methods: This study involved 36 CEI races and 283 horses (41 eliminated because of metabolic disturbances). Blood samples were taken before competition, after the vet-gates and after finishing the race or veterinary disqualification. Packed cell volume (PCV), activities of CK, AST and LDH, and concentrations of total plasma proteins (PP), urea, creatinine (Cr), uric acid (UA) and plasma lactate were determined. Successful horses were compared with horses eliminated due to metabolic conditions in the values obtained in the phase prior to being removed from the competition. Factors associated with metabolic elimination were further analysed using multiple logistic regression analysis. Dichotomisation for each variable was made using the receiver-operating characteristic curve to enter into the model. Results: PCV>52%, PP>82 g/l, standardised Cr>30 mg/l 100 km, UA>72 mg/l, standardised CK>12.6 ui/l km and standardised AST>6.2 ui/l km were associated with the development of metabolic alterations. Of the horses with an imbalance between PCV and PP, 30% had metabolic elimination in the following phases. Muscle enzymes and Cr were directly related to the distance covered. Conclusions: Selected biochemical markers are evident in some endurance horses before their elimination. However, most horses developed metabolic disturbances without any important alterations in the variables determined in this study. Potential relevance: Analysis of selected plasma biochemical parameters could be useful in the prevention and early diagnosis of metabolic stress in endurance horses.

The renin–angiotensin–aldosterone–vasopressin axis (RAAV) is known to play significant roles in preserving hemodynamic stability in response to changes in blood volume, blood pressure, electrolytes, and water. In the previous years, some studies focused on RAAV in the horse, showing substantial future clinical and research applications. Early studies assessed the response of this axis to different types of exercise (increasing intensity exercise vs. endurance). Aldosterone and vasopressin concentrations were measured in horses with mild dehydration induced by endurance exercise in comparison with horses suffering from exhaustion and metabolic problems after prolonged exercise. More recently, the neurohumoral response to heart failure, mainly in congestive states, has received special attention. The activation of the RAAV in congestive heart failure has important prognosis applications and inhibitors of this axis have been clinically studied, as the angiotensin-converting enzyme inhibitors. However, inhibitors of renin, aldosterone, and vasopressin have not been studied in horses. Additionally, the investigation of the changes in blood pressure during dehydration, sepsis, and endotoxemia in foals and adult horses might show important applications in the treatment of states that induce modifications in blood pressure. Inappropriately low RAAV activity has been detected in human patients with prolonged vasodilatory shock, and exogenously administered vasopressin could be used as a potent vasopressor agent to stabilize cardio-circulatory function. Similarly, it might be administered to septic foals for similar purposes. Finally, the RAAV axis also has important implications in the development as well as in the treatment of the chronic renal failure, although it has not been investigated in horses.

Summary Reason for performing study: Limited information exists concerning the defence of homeostasis during endurance competitions and the relationship with performance. Objectives: This research analysed renin (REN), angiotensin II (ANG), aldosterone (ALD) and vasopressin (AVP) in horses covering different distances, assesses differences between successful and eliminated horses and evaluates correlations between hydration status, renal function, electrolytes, REN, ANG, ALD and AVP. Methods: Packed cell volume (PCV), velocity and serum concentrations of REN, ANG, ALD, AVP, Na, K, Cl, Ca, Mg, P, creatine kinase, aspartate aminotransferase, lactate dehydrogenase, total proteins (TSP), albumin (ALB), serum ureic nitrogen (SUN), creatinine (CREAT) and lactate were analysed in both successful horses (SH) and in horses eliminated due to metabolic problems (MH). Two types of competition were studied: 91 km in one day (Competition A: 20 SH, 9 MH) and 166 km in 2 days, 83 km/day (Competition B :1 0 SH and 5M H). Results: Research analysed renin was not affected by exercise, whereas ANG, ALD and AVP increased. In the SH group, resting ALD and AVP concentrations at the beginning of the second day of Competition B were higher than preride values. Vasopressin did not change during the second day of Competition B, whereas ALD progressively increased. Metabolic problems of both groups showed more evident dehydration (higher PCV, TSP, ALB, SUN and CREAT) and electrolyte alterations (more intense decreases of Na and Cl) than SH at the different sampling times. Metabolic problems presented higher ALD and AVP concentrations. Angiotensin II was higher at certain sampling times in the horses. Conclusions: Endurance horses with dehydration and electrolyte disturbances showed a more intense activation of the REN-ANG-ALD-AVP axis. Potential relevance: The study of the response of the REN- ANG-ALD-AVPaxis during prolonged exercise in horses with different performance will aid to minimise the risk of metabolic diseases during competitions.

Hematology and serum/plasma biochemistry are important diagnostic aids to assess metabolic status in starved horses and to rule out pathologic conditions that present as emaciation. This article reviews the interpretation of these parameters, using 10 chronically starved horses as examples. The study was conducted on these 10 neglected horses belonging to both sexes, aged between 4 and 25 years. The animals were divided into two groups according to their body condition scoring (BCS): A (n = 6; BCS of 3 or lower) and B (n = 4; BCS higher than 3). A complete clinical examination was carried out, and venous blood samples were taken to perform hematological, biochemical, and serological determinations. The findings indicated that the most emaciated horses (group A) presented normocytic normochromic anemia, with higher numbers of both immature and mature neutrophils, monocytes, and eosinophils, and lower number of lymphocytes. Furthermore, horses in group A showed lower serum concentrations of urea, triglycerides, bile acids, alkaline phosphatase, and a lower urea/creatinine ratio. Both groups of horses presented with hypomagnesemia. In conclusion, the knowledge of the laboratorial findings in emaciated horses is useful in scoring the intensity of the emaciation, and in establishing a prognosis and a plan to recover the health status of these animals.