A simple analytical method for simultaneous determination of phytosterols, cholesterol and squalene in lipid emulsions was developed owing to increased interest in their clinical effects. Method development was based on commonly used stationary (C , C and phenyl) and mobile phases (mixtures of acetonitrile, methanol and water) under isocratic conditions. Differences in stationary phases resulted in peak overlapping or coelution of different peaks. The best separation of all analyzed compounds was achieved on Zorbax Eclipse XDB C (150 × 4.6 mm, 5 μm; Agilent) and ACN-H O-MeOH, 80:19.5:0.5 (v/v/v). In order to achieve a shorter time of analysis, the method was further optimized and gradient separation was established. The optimized analytical method was validated and tested for routine use in lipid emulsion analyses.

Vegetable lipid emulsions (LE) contain non-declared phytosterols (PS). We aimed to determine PS content depending on the brand and LE batch, and in adult hospitalised patients treated with parenteral nutrition (PN), to establish the association between plasma and administered PS. Part I was the LE study: totals and fractions of PS in three to four non-consecutive batches from six LE were analysed. Part II was the patient study: patients with at least 7 previous days of PN with 0·8 g/kg per d of an olive/soyabean (O/S) LE were randomised (day 0) 1:1 to O/S or 100 % fish oil (FO) at a dose of 0·4 g/kg per d for 7 d (day 7). Plasma PS, its fractions, total cholesterol on days 0 and 7, their clearance and their association with PS administered by LE were studied. In part I, LE study: differences were found in the total PS, their fractions and cholesterol among different LE brands and batches. Exclusive soyabean LE had the highest content of PS (422·36 (sd 130·46) μg/ml). In part II, patient study: nineteen patients were included. In the O/S group, PS levels were maintained (1·11 (sd 6·98) μg/ml) from day 0 to 7, while in the FO group, significant decreases were seen in total PS (−6·21 (sd 4·73) μg/ml) and their fractions, except for campesterol and stigmasterol. Plasma PS on day 7 were significantly associated with PS administered (R2 0·443). PS content in different LE brands had great variability. PS administered during PN resulted in accumulation and could be prevented with the exclusive administration of FO LE.

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Introducción: El patrón de ácidos grasos (AG) de las emulsiones lipídicas (EL) utilizadas en Nutrición Parenteral (NP) condiciona diferentes respuestas fisiológicas.Objetivos: Valorar la adecuación de un protocolo clínico no restringido en la elección de EL mediante el estudio de parámetros bioquímicos y hematológicos específicos (PBHE) al inicio de la NP.Métodos: Estudio observacional retrospectivo de 4 años. Se recogieron variables demográficas, clínicas, nutricionales y analíticas al inicio de la NP. En pacientes con valores  iniciales de los PBHE, se hizo un análisis univariante y multivariante para estudiar la asociación entre sus valores iniciales y el patrón lipídico utilizado.Resultados: De los 1558 pacientes, 460 pacientes (29,5%) tenían PBHE al inicio de la NP y utilizaron mayoritariamente las combinaciones soja (AS)+triglicéridos de cadena media (MCT)+oliva (AO)+pescado (AP) (37,4%) y AS+MCT+AO (35,6%). Se encontraron diferencias estadísticamente significativas en el patrón EL utilizado entre los pacientes con y sin PBHE: patrón de AG  con AP 44,8% vs 39,5%, respectivamente.Las situaciones clínicas con proteína C-reactiva (PCR) elevada se asociaron con mayor uso de EL con AP: AS+AO+AP (OR:4,52 [IC 95%: 1,43-13,91] y AS+MCT+AO+AP (OR:3,34 [IC 95%: 2,10-5,33]). En situaciones clínicas complejas asociadas con paciente crítico se utilizaron EL con MCT: fracaso hepático (AS+MCT OR:2,42 [IC95%: 1,03-5,68]) y fracaso renal (AS+MCT+AP OR:3.34 [IC95%: 1,12-9.99]).Conclusiones: La inclusión protocolizada de PBHE al inicio de la NP permite complementar criterios clínicos y metabólicos en la elección de la EL.

Site-selective, dual-conjugation approaches for the incorporation of distinct payloads are key for the development of molecularly targeted biomolecules, such as antibody conjugates, endowed with better properties. Combinations of cytotoxic drugs, imaging probes, or pharmacokinetics modulators enabled for improved outcomes in both molecular imaging, and therapeutic settings. We have developed an efficacious dual-bioconjugation strategy to target the N-terminal cysteine of a chemically-synthesized, third-generation anti-HER2 affibody. Such two-step, one-purification approach can be carried out under mild conditions (without chaotropic agents, neutral pH) by means of a slight excess of commercially available N-hydroxysuccinimidyl esters and maleimido-functionalized payloads, to generate dual conjugates displaying drugs (DM1/MMAE) or probes (sulfo-Cy5/biotin) in high yield and purity. Remarkably, the double drug conjugate exhibited an exacerbated cytoxicity against HER2-expressing cell lines as compared to a combination of two monoconjugates, demonstrating a potent synergistic effect. Consistently, affibody-drug conjugates did not decrease the viability of HER2-negative cells, confirming their specificity for the target.