Interactions of human serum albumin with phosphate and Tris buffers: impact on paclitaxel binding and nanoparticles self-assembly.

AIM: To investigate the conformational changes in human serum albumin (HSA) caused by chemical (CD) and thermal denaturation (TD) at pH 7.4 and 9.9, crucial for designing controlled drug delivery systems with paclitaxel (PTX). METHODS: Experimental and computational methods, including differential scanning calorimetry (DSC), UV-Vis and intrinsic fluorescence spectroscopy, mean diameter, polydispersity index (PDI), ζ-potential, encapsulation efficiency (EE), in vitro release and protein docking studies were conducted to study the HSA denaturation and nanoparticles (NPs) preparation. RESULTS: TD at pH 7.4 produced smaller NPs (287.1 ± 12.9 nm) than CD at pH 7.4 with NPs (584.2 ± 47.7 nm). TD at pH 9.9 exhibited high EE (97.3 ± 0.2%w/w) with rapid PTX release (50% within 1h), whereas at pH 7.4 (96.4 ± 2.1%w/w), release only 40%. ζ-potentials were around -30 mV. CONCLUSION: Buffer type and pH significantly influence NP properties. TD in PBS at pH 7.4, provided optimal conditions for a stable and efficient drug delivery system.

Impact of nanosilver surface electronic distributions on serum protein interactions and hemocompatibility.

The translation of silver-based nanotechnology 'from bench to bedside' requires a deep understanding of the molecular aspects of its biological action, which remains controversial at low concentrations and non-spherical morphologies. Here, we present a hemocompatibility approach based on the effect of the distinctive electronic charge distribution in silver nanoparticles (nanosilver) on blood components. According to spectroscopic, volumetric, microscopic, dynamic light scattering measurements, pro-coagulant activity tests, and cellular inspection, we determine that at extremely low nanosilver concentrations (0.125-2.5µg ml-1), there is a relevant interaction effect on the serum albumin and red blood cells (RBCs). This explanation has its origin in the surface charge distribution of nanosilver particles and their electron-mediated energy transfer mechanism. Prism-shaped nanoparticles, with anisotropic charge distributions, act at the surface level, generating a compaction of the native protein molecule. In contrast, the spherical nanosilver particle, by exhibiting isotropic surface charge, generates a polar environment comparable to the solvent. Both morphologies induce aggregation at NPs/bovine serum albumin ≈ 0.044 molar ratio values without altering the coagulation cascade tests; however, the spherical-shaped nanosilver exerts a negative impact on RBCs. Overall, our results suggest that the electron distributions of nanosilver particles, even at extremely low concentrations, are a critical factor influencing the molecular structure of blood proteins' and RBCs' membranes. Isotropic forms of nanosilver should be considered with caution, as they are not always the least harmful.

Clinical Characteristics of Genuine Acute Autoimmune Hepatitis.

Introduction: Autoimmune hepatitis (AIH) has a spectrum of symptoms ranging from asymptomatic disease to acute severe hepatitis, chronic hepatitis, and decompensated cirrhosis. The acute presentation is not rare and could represent genuine acute AIH (GAAIH) or acute exacerbation of chronic autoimmune hepatitis. We aimed to identify the prevalence, clinical features, and prognostic factors associated with GAAIH and compare these cases with acute exacerbation of chronic AIH. Methods: This cross-sectional observational study evaluated patients with acute AIH presentation, defined as total bilirubin >5 times the upper limit of normality (xULN) and/or alanine aminotransferase >10 xULN, and no prior history of liver disease. Histology findings of acute disease defined GAAIH. Bivariate analyses were performed to identify factors associated with the GAAIH, when compared with acute exacerbation of chronic AIH. Results: Seventy-two patients with acute presentation of AIH were included and six (8.3%) of them presented GAAIH. Comparative analysis between patients with GAAIH and patients with acute exacerbation of chronic AIH revealed that prothrombin activity (96% [74-100] vs. 61% [10-100]; p = 0.003) and albumin levels (3.9 ± 0.2 g/dL vs. 3.4 ± 0.5 g/dL; p < 0.001) were higher in patients with GAAIH. The International Autoimmune Hepatitis Group score was higher in patients with acute exacerbation of chronic AIH (18.5 [8-23] vs. 16.5 [15-17]; p = 0.010). Compared to 15.2% of acute exacerbation of chronic AIH, complete therapeutic response to treatment was achieved in 67.7% of cases with GAAIH (p = 0.018). Conclusions: GAAIH was rare (8.3%), and patients with this presentation exhibited more preserved liver function tests, suggesting that most cases presenting with loss of function are acute exacerbation of chronic AIH. Additionally, patients with GAAIH had a better complete therapeutic response, suggesting a more preserved liver function at presentation, and early diagnosis has a positive therapeutic implication.

Introdução: A hepatite autoimune (HAI) apresenta um espectro de sintomas que varia de doença assintomática a hepatite aguda grave, hepatite crónica e cirrose descompensada. A apresentação aguda não é rara e pode representar hepatite autoimune aguda genuína (HAIAG) ou exacerbação aguda de hepatite autoimune crónica (EAHAIC). O nosso objetivo foi identificar a prevalência, caraterísticas clínicas e fatores prognósticos associados à HAIAG, e comparar esses casos com EAHAIC. Métodos: Estudo observacional, transversal, incluindo doentes com apresentação aguda de HAI, definida como bilirrubina total > 5 vezes o limite superior da normalidade (xLSN) e/ou ALT > 10 xLSN, e sem história prévia de doença hepática. HAIAG foi definida pela presença de achados histológicos de doença aguda. Análises bivariadas foram realizadas para identificar fatores associados à HAIAG, quando comparado com o EAHAIC. Resultados: Foram incluídos setenta e dois doentes com apresentação aguda de HAI, dos quais seis (8.3%) com HAIAG. A análise comparativa entre doentes com HAIAG e doentes com EAHAIC mostrou que a atividade de protrombina (96% (74-100) versus 61% (10-100; p=0.003) e os níveis de albumina (3,9 ± 0,2 g/dL vs. 3,4 ± 0,5 g/dL; p < 0,001) foram significativamente mais elevados em pacientes com HAIAG. O score do Grupo Internacional de Hepatite Autoimune foi mais elevado em doentes com EAHAIC (18.5 (8-23) versus 16.5 (15-17); p=0.010). A resposta terapêutica completa ao tratamento foi alcançada em 66.7% dos casos de HAIAG (vs. 15,2% na EAHAIC, p=0,018). Conclusões: A HAIAG é rara (8.3%), e os doentes com esta apresentação mostraram testes de função hepática mais preservados, sugerindo que a maioria dos casos com perda de função são EAHAIC. Além disso, os doentes com HAIAG tiveram maior taxa de resposta terapêutica completa, sugerindo que uma função hepática mais preservada na apresentação e o diagnóstico precoce tem uma implicação terapêutica positiva.

Design and characterization of BSA-mycophenolic acid nanocomplexes: Antiviral activity exploration.

The interactions between bovine serum albumin (BSA) and mycophenolic acid (MPA) were investigated in silico through molecular docking and in vitro, using fluorescence spectroscopy. Dynamic light scattering and scanning electron microscopy were used to figure out the structure of MPA-Complex (MPA-C). The binding affinity between MPA and BSA was determined, yielding a Kd value of (12.0 ± 0.7) µM, and establishing a distance of 17 Å between the BSA and MPA molecules. The presence of MPA prompted protein aggregation, leading to the formation of MPA-C. The cytotoxicity of MPA-C and its ability to fight Junín virus (JUNV) were tested in A549 and Vero cell lines. It was found that treating infected cells with MPA-C decreased the JUNV yield and was more effective than free MPA in both cell line models for prolonged time treatments. Our results represent the first report of the antiviral activity of this type of BSA-MPA complex against JUNV, as assessed in cell culture model systems. MPA-C shows promise as a candidate for drug formulation against human pathogenic arenaviruses.

Chiral separation of propranolol by electrokinetic chromatography using nanodiamonds and human serum albumin as a pseudo-stationary phase in river water.

Propranolol is currently considered as an emerging contaminant in water bodies. In this study, R- and S-propranolol were determined in river samples by electrokinetic chromatography (EKC) using nanodiamonds (NDs) and human serum albumin (HSA) as a pseudo-stationary phase in order to achieve enantioseparation. Previously, river samples were preconcentrated using a column filled with Amberlite® IR-120 and Dowex® 50WX8 resins. The setting up of influential factors such as temperature, voltage, pH, and HSA and NDs concentration is accurately described along this manuscript. A multivariate study and optimization was carried out to obtain the enantioseparation of propranolol (Rs = 2.91), which was reached under the following experimental conditions: voltage of 16 kV, temperature of 16°C, phosphate buffer pH 9.5, NDs of 0.20%, and HSA of 15 µmol l-1 . The recoveries of analytes under optimal conditions were higher than 98%. The limits of detection were 0.85 µg l-1 for R- and S-propranolol. The method was applied to real samples, and the obtained results in three different water sources studied were 1.02, 0.59, and 0.30 µg l-1 for the R-enantiomer and 0.99, 0.54, and 0.28 µg l-1 for the S-enantiomer. The accuracy of the proposed methodology (including bias and precision) has allowed us to propose it as a successful tool for the control of water quality.

Albúmina en cirrosis: perspectiva inflamatoria / Albumin in cirrhosis: inflammatory perspective

La albúmina sérica humana es la proteína más abundante en el plasma, su estructura molecular le confiere estabilidad, pero también flexibilidad para ligar y transportar un amplio rango de moléculas. Su función oncótica es la propiedad más reconocida que la lleva a introducirse en la terapéutica médica como un expansor de volumen. Sin embargo, en los últimos años se le han adicionado funciones con carácter antioxidante, inmunomodulador y de estabilización endotelial, que hacen presumir que su impacto terapéutico está más allá de sus funciones volumétricas. En los últimos años, específicamente en la cirrosis y la falla hepática aguda sobre crónica, se ha tenido un cambio en el paradigma fisiológico, desde una perspectiva netamente hemodinámica hacia una perspectiva inflamatoria, en donde las funciones oncóticas y no oncóticas de la albúmina están alteradas y tienen un carácter pronóstico en estas entidades. Este conocimiento creciente, desde una perspectiva inflamatoria, hace que se fortalezca el uso terapéutico de la albúmina sérica humana desde las indicaciones tradicionales como prevención de la disfunción circulatoria posparacentesis, prevención y tratamiento de lesión renal aguda, hasta las discusiones para administración a largo plazo en pacientes cirróticos con ascitis.

Human serum albumin is the most abundant protein in plasma, with a molecular structure that provides stability while also allowing flexibility to bind and transport a wide range of molecules. Its oncotic function is the most recognized property, leading to its introduction in medical therapy as a volume expander. However, in recent years, additional functions with antioxidant, immunomodulatory, and endothelial stabilization properties have been identified, suggesting that its therapeutic impact extends beyond its volumetric functions. Specifically, in cirrhosis and acute-on-chronic liver failure, there has been a shift in the pathophysiological paradigm from a purely hemodynamic perspective to an inflammatory perspective, where both oncotic and non-oncotic functions of albumin are altered and have prognostic significance in these conditions. This growing understanding from an inflammatory perspective strengthens the therapeutic use of human serum albumin, not only for traditional indications such as the prevention of post-paracentesis circulatory disfunction, prevention and treatment of acute kidney injury, but also for discussions regarding long-term administration in cirrhotic patients with ascites.

Ordered mesoporous silicas for potential applications in solid vaccine formulations.

In an effort to develop efficient vaccine formulations, the use of ordered mesoporous silica (SBA-15) as an antigen carrier has been investigated. SBA-15 has required properties such as high surface area and pore volume, including narrow pore size distribution to protect antigens inside its matrix. This study aimed to examine the impact of solvent removal methods, specifically freeze-drying and evaporation on the intrinsic properties of an immunogenic complex. The immunogenic complexes, synthesized and incorporated with BSA, were characterized by various physicochemical techniques. Small Angle X-ray Scattering measurements revealed the characteristic reflections associated to pure SBA-15, indicating the preservation of the silica mesostructured following BSA incorporation and the formation of BSA aggregates within the macropore region. Nitrogen Adsorption Isotherm measurements demonstrated a decrease in surface area and pore volume for all samples, indicating that the BSA was incorporated into the SBA-15 matrix. Fluorescence spectroscopy evidenced that the tryptophan residues in BSA inside SBA-15 or in solution displayed similar spectra, showing the preservation of the aromatic residues' environment. The Circular Dichroism spectra of BSA in both conditions suggest the preservation of its native secondary structure after the encapsulation process. The immunogenic analysis with the detection of anti-BSA IgG did not give any significant difference between the non-dried, freeze-dried or evaporated groups. However, all groups containing BSA and SBA-15 showed results almost three times higher than the groups with pure BSA (control group). These facts indicate that none of the BSA incorporation methods interfered with the immunogenicity of the complex. In particular, the freeze-dried process is regularly used in the pharmaceutical industry, therefore its adequacy to produce immunogenic complexes was proved Furthermore, the results showed that SBA-15 increased the immunogenic activity of BSA.

Ordered mesoporous silicas for potential applications in solid vaccine formulations

In an effort to develop efficient vaccine formulations, the use of ordered mesoporous silica (SBA-15) as an antigen carrier has been investigated. SBA-15 has required properties such as high surface area and pore volume, including narrow pore size distribution to protect antigens inside its matrix. This study aimed to examine the impact of solvent removal methods, specifically freeze-drying and evaporation on the intrinsic properties of an immunogenic complex. The immunogenic complexes, synthesized and incorporated with BSA, were characterized by various physicochemical techniques. Small Angle X-ray Scattering measurements revealed the characteristic reflections associated to pure SBA-15, indicating the preservation of the silica mesostructured following BSA incorporation and the formation of BSA aggregates within the macropore region. Nitrogen Adsorption Isotherm measurements demonstrated a decrease in surface area and pore volume for all samples, indicating that the BSA was incorporated into the SBA-15 matrix. Fluorescence spectroscopy evidenced that the tryptophan residues in BSA inside SBA-15 or in solution displayed similar spectra, showing the preservation of the aromatic residues’ environment. The Circular Dichroism spectra of BSA in both conditions suggest the preservation of its native secondary structure after the encapsulation process. The immunogenic analysis with the detection of anti-BSA IgG did not give any significant difference between the non-dried, freeze-dried or evaporated groups. However, all groups containing BSA and SBA-15 showed results almost three times higher than the groups with pure BSA (control group). These facts indicate that none of the BSA incorporation methods interfered with the immunogenicity of the complex. In particular, the freeze-dried process is regularly used in the pharmaceutical industry, therefore its adequacy to produce immunogenic complexes was proved Furthermore, the results showed that SBA-15 increased the immunogenic activity of BSA.

Bi-coloured enhanced luminescence imaging by targeted switch on/off laser MEF coupling for synthetic biosensing of nanostructured human serum albumin.

In this communication luminescent bioconjugated human serum albumin nanostructures (HSA NPs) with tiny ultraluminescent gold core-shell silica nanoparticles (Au@SiO2-Fl) were designed with enhanced bi-coloured luminescence properties. The HSA NPs were obtained from Human Serum Albumin free (HSA free) through the desolvation method, and Au@SiO2-Fl, through modified Turkevich and Störber methods. In this manner, porous HSA Nanostructures of 150.0-200 nm and Au@SiO2-Fl 45.0 nm final diameters were obtained. Both methodologies and structures were conjugated to obtain modified Nanocomposites based on tiny gold cores of 15 nm surrounded with well spatial Nanostructured architectures of HSA (d15 Au@SiO2-Fl-HSA) that generated variable nanopatterns depending on the modified methodology of synthesis applied within colloidal dispersions. Therefore, three methodologies of non-covalent conjugation were developed. In optimal conditions, through Transmission Electronic Microscopy (TEM), well resolved multilayered nano-architectures with a size 190.0-200 nm in average with variable contrast depending of the focused nanomaterial within the nanocomposite were shown. Optimized nanoarchitecture was based on a template tiny gold core-shell surrounded by nanostructured HSA NPs (d15 Au@SiO2-Fl-HSA). In this manner, the NanoImaging generated by laser fluorescence microscopy permitted to record improved optical properties and functionalities, such as: (i) enhanced ultraluminescent d15 Au@SiO2-Fl-HSA composites in comparison to individual components based on Metal Enhanced Fluorescence (MEF); (ii) diminished photobleaching; (iii) higher dispersibility; (iv) higher resolution of single bright nano-emitters of 210.0 nm sizes; and (v) enhanced bi-coloured Bio-MEF coupling with potential non-classical light delivery towards other non-optical active biostructures for varied applications. The characterization of these nanocomposites allowed the comparison, evaluation and discussion focused on new properties generated and functionalities based on the incorporation of different types of tuneable materials. In this context, the biocompatibility, Cargo confined spaces, protein-based materials, optical transparent could be highlighted, as well as optical active materials. Thus, the potential applications of nanotechnology to both nanomedicine and nano-pharmaceutics were discussed.

DFT calculations of copper complexes mimicking superoxide dismutase and docking studies and molecular dynamics of the transition metal complex binding to serum albumin.

Superoxide dismutase (SOD) is a metalloenzyme whose antioxidant activity is mimicked by some transition metal complexes, and such ability can be added in proteins such as the bovine serum albumin (BSA), creating a hybrid protein. In this work, density functional theory (DFT) calculations of three Cu(II)-complexes of general formula [CuL2phen] (phen = phenanthroline; C1, L = mefenamate; C2, L = tolfenamate; C3, L = flufenamate) with SOD-like activity, and docking and molecular dynamics (MD) simulations of these complexes with the BSA were performed. The DFT calculations revealed that the complex reduction involves Cu(II) → Cu(I) reduction, the theoretical electron affinity (EA) correlated with the SOD-like activity (IC50), and the contribution of the phenanthroline ligand and the metal in LUMO it's related with the complex-protein interaction (KVS). The docking and MD simulations revealed the binding site of the complexes in BSA and the residues involved in the binding. The stability of the Cu(II) and Cu(I) forms of the complexes in the site indicated that the catalysis promoted by these complexes occurs in the same region of the BSA and that their mimetic activity can be incorporated into BSA, creating a hybrid protein (BSA with SOD activity)Communicated by Ramaswamy H. Sarma.

Análise de custos de pacientes cirróticos descompensados recebendo albumina a longo prazo versus tratamento médico padrão nos sistemas de saúde público e privado do Brasil / Albumin versus standard medical treatment in brazilian public and private healthcare systems

ABSTRACT Background: Cirrhosis is one of the final stages of chronic liver disease. Common causes of cirrhosis include alcoholism and viral hepatitis infections. Cirrhosis can progress from an asymptomatic, compensated phase to decompensation and the appearance of overt symptoms. There is no specific treatment for decompensated cirrhosis. The ANSWER trial positioned long-term albumin infusions as a potential treatment for patients with cirrhosis and uncomplicated ascites. Objective: This study assesses the economic impact of albumin infusions following the ANSWER trial regimen in Brazilian patients with decompensated cirrhosis from the public and private healthcare systems perspectives. Methods: The incremental cost per patient per year was calculated for standard medical treatment (SMT) plus long-term albumin infusions versus SMT alone. Costs of diuretics and albumin were obtained from Banco de Preços em Saúde and the Drug Market Regulation Chamber. Costs for complication and procedures were gathered from the published literature. Costs were transformed to 2021 Brazilian reals (BRL). Incidences of clinical complications and treatments were gathered from the ANSWER trial. Univariate sensitivity analysis was performed by increasing and decreasing all inputs by 20%. Results: The cost per patient per year was 118,759 BRL and 189,675 BRL lower for patients treated with SMT and albumin (compared to SMT only) for the public and private healthcare systems, respectively. The additional cost of albumin was offset by reduced complications and treatments (149,526 BRL and 249,572 BRL, respectively). The univariate sensitivity analysis showed cost savings for both healthcare systems in all the scenarios assessed. Conclusion: This economic analysis suggests that, if the ANSWER trial clinical outcomes translate into real-world effectiveness, addition of albumin infusions to SMT in patients with decompensated cirrhosis may lead to cost savings for the public and private healthcare systems in Brazil.

RESUMO Contexto: A cirrose representa o estágio final da doença hepática crônica. Causas comuns de cirrose incluem alcoolismo e infecções por hepatite viral. A cirrose pode progredir de uma fase compensada assintomática para descompensação e aparecimento de sintomas evidentes. Não há tratamento específico para cirrose descompensada. O estudo ANSWER demonstrou que a administração de albumina a longo prazo pode representar um potencial tratamento para pacientes com cirrose e ascite não complicada. Objetivo: Nosso estudo avalia o impacto econômico da administração de albumina a longo prazo seguindo o protocolo do estudo ANSWER em pacientes brasileiros com cirrose descompensada, sob a perspectiva dos sistemas de saúde público e privado. Métodos: O custo incremental por paciente por ano foi calculado para o tratamento médico padrão (SMT) associado a administração de albumina a longo prazo comparado a SMT apenas. Os custos de diuréticos e albumina foram obtidos no Banco de Preços em Saúde e na Câmara de Regulação do Mercado de Medicamentos. Os custos de complicações e procedimentos foram coletados da literatura publicada. Os custos foram transformados em Reais de 2021 (BRL). As incidências de complicações clínicas e tratamentos foram coletadas do estudo ANSWER. Uma análise de sensibilidade univariada foi realizada aumentando e diminuindo todas as variáveis em 20%. Resultados: O custo por paciente por ano foi de R$ 118.759 e R$ 189.675 menor para pacientes tratados com SMT e albumina (comparado apenas com SMT) para os sistemas de saúde público e privado, respectivamente. O custo adicional da albumina foi compensado pela redução de complicações e tratamentos (149.526 BRL e 249.572 BRL, respectivamente). A análise de sensibilidade univariada mostrou redução de custos para ambos os sistemas de saúde em todos os cenários avaliados. Conclusão: Esta análise econômica sugere que, se os resultados clínicos do estudo ANSWER se confirmarem no mundo real, a administração de albumina associada ao SMT em pacientes com cirrose descompensada pode levar a redução de custos para os sistemas de saúde público e privado no Brasil.

Night fasting as an alternative to improve nutritional support and glycaemic control in hospitalised patients with exclusive enteral nutrition.

BACKGROUND: Enteral nutrition (EN) assists in the nutritional status of hospitalised patients unable to feed orally. The aim of this study was to determine which method-continuous EN or discontinuous EN, a diet in which the infusion is discontinued for 4h during the night,-is more effective in meeting nutrient recommendations and improving glycaemic control and biochemical parameters related to protein anabolism. METHODS: Patients were divided into two groups: discontinuous (EN administered in mL/h, 18h/day, 4-h night fasting) and continuous (EN administered in mL/h, 22h/day). All patients with EN receive the diet over a 22-h daily period, in which the diet is suspended for two hours/day for daily hospital routines such as bathing, and physiotherapy, and followed for seven days. Evaluated data: prescribed and administered volume, calories, protein, and fibre; capillary blood glucose; erythrogram; serum albumin. RESULTS: 52 patients were followed-up, with 23 (44.2%) in the discontinuous group and 29 (55.8%) in the continuous group. Compared with the continuous group, the discontinuous group received volumes closer to those prescribed, equal or higher calories, and more protein. The capillary glucose values were within the reference range in the discontinuous group, while the continuous group presented elevated values. Both groups presented hypoalbuminaemia, haemoglobin, and haematocrit below the reference values; however, in the discontinuous group, the serum albumin values improved during hospitalisation relative to the continuous. CONCLUSIONS: The method involving discontinuation of EN for 4h was more effective in meeting nutrient recommendations compared with the continuous method. Additionally, in the discontinuous group, we observed a better control of glycaemia when compared to that of the continuous group.

Albúmina sérica predictor de resultados intrahospitalarios en pacientes admitidos a la UCIN del Hospital de la Mujer / Serum albumin predicator of intrahospital outcomes in patients admitted to the NICU of the women's hospital

INTRODUCCIÓN: En el estrés metabólico existe una sobreproducción proteica de reactantes positivos de la fase aguda y en el hígado, se frena la síntesis de otras proteínas, incluyendo la albúmina, denominadas Reactantes Negativos de la Fase Aguda. Los rangos de referencia precisos para la hipoalbuminemia patológica han resultado difíciles de determinar en los recién nacidos. MATERIAL Y MÉTODOS: Descriptivo de corte transversal en 494 recién nacidos. Se realizó un análisis exploratorio de los datos con estadística descriptiva mediante el paquete estadístico SPSS v.20. RESULTADOS: 494 neonatos fueron seleccionados, 39% fueron prematuros tardíos, 27% reportó hipoalbuminemia en sus diferentes grados que se correlacionaron con los días de internación en UCIN (p=0,0001), necesidad y tiempo en ventilador mecánico (p=0,001), con la mortalidad (p=0,001) y patología infecciosa (p=0,001). DISCUSIÓN: La incidencia acumulada de sepsis no confirmada por hemocultivo fue de 54%, La hipoalbuminemia tiene asociaciones importantes con la evolución y pronóstico en pacientes pediátricos. La PCR no tiene correlación en el estudio (p=0,232) y solo fue reactiva en 4 pacientes (0,8%). CONCLUSIONES: El nivel de albúmina sérica reportada en las primeras 24 horas de ingreso a la UCIN es un predictor para los resultados intrahospitalarios (tiempo y requerimiento de ventilación mecánica), mortalidad neonatal, sepsis neonatal y enfermedad de membrana hialina. Su determinación sérica debe ser incluida en la lista de exámenes de laboratorio solicitados a su admisión y la PCR al ingreso debe ser excluida por su pobre sensibilidad como sugiere la SIBEN.

INTRODUCTION: In metabolic stress, there is a protein overproduction of positive acute phase reactants and in the liver, the synthesis of other proteins, including albumin, called negative acute phase reactants is slowed down. Precise reference ranges for pathologic hypoalbuminemia have proven difficult to determine in neonates. MATERIAL AND METHODS: Descriptive cross section in 494 newborns. An exploratory analysis of the data with descriptive statistics was carried out using the statistical package SPSS v.20. RESULTS: 494 neonates were selected, 39% were late preterm, 27% reported hypoalbuminemia in its different degrees that correlated with the days of hospitalization in the NICU (p=0.0001), need and time on a mechanical ventilator (p=0.001), with mortality (p=0.001) and infectious pathology (p=0.001). DISCUSSION: The cumulative incidence of sepsis not confirmed by blood culture was 54%. Hypoalbuminemia has important associations with outcome and prognosis in pediatric patients. CRP does not correlate the study (p=0.232) and was only reactive in 4 patients (0.8%). CONCLUSIONS: Serum albumin level reported in the first 24 hours of NICU admission is a predictor for in-hospital outcomes (time and requirement of mechanical ventilation), neonatal mortality, neonatal sepsis, and hyaline membrane disease. Its serum determination should be included in the list of laboratory tests requested upon admission and the PCR upon admission should be excluded due to its poor sensitivity, as suggested by SIBEN.

Direct Oral FXa Inhibitors Binding to Human Serum Albumin: Spectroscopic, Calorimetric, and Computational Studies.

Direct FXa inhibitors are an important class of bioactive molecules (rivaroxaban, apixaban, edoxaban, and betrixaban) applied for thromboprophylaxis in diverse cardiovascular pathologies. The interaction of active compounds with human serum albumin (HSA), the most abundant protein in blood plasma, is a key research area and provides crucial information about drugs' pharmacokinetics and pharmacodynamic properties. This research focuses on the study of the interactions between HSA and four commercially available direct oral FXa inhibitors, applying methodologies including steady-state and time-resolved fluorescence, isothermal titration calorimetry (ITC), and molecular dynamics. The HSA complexation of FXa inhibitors was found to occur via static quenching, and the complex formation in the ground states affects the fluorescence of HSA, with a moderate binding constant of 104 M-1. However, the ITC studies reported significantly different binding constants (103 M-1) compared with the results obtained through spectrophotometric methods. The suspected binding mode is supported by molecular dynamics simulations, where the predominant interactions were hydrogen bonds and hydrophobic interactions (mainly π-π stacking interactions between the phenyl ring of FXa inhibitors and the indole moiety of Trp214). Finally, the possible implications of the obtained results regarding pathologies such as hypoalbuminemia are briefly discussed.

Pork-cat syndrome as cause of anaphylactic reaction to well-cooked meat / Síndrome gato-porco como causa de reação anafilática à carne cozida

Pork-cat syndrome is a rare clinical syndrome that can cause lifethreatening reactions. Occuring in patients allergic to cat dander, it involves cross-reactivity between cat and pig serum albumin. Cat allergy usually precedes food allergies, suggesting primary sensitization to cat serum albumin. Since these proteins are thermolabile, the reaction tends to be more severe in undercooked meat. A 27-year-old woman with persistent moderate-to-severe rhinoconjunctivitis since childhood reported 2 immediate mucocutaneous reactions after eating small amounts of pork. Skin prick tests with commercial extracts showed sensitization to pork, and prick-to-prick tests confirmed sensitization to raw pork and raw beef. Specific IgE was positive for pork, and ISAC microarray also showed sensitization to Fel d 2. SDS-PAGE and IgE immunoblotting assays were performed with raw and cooked pork extract and detected in a 60 kDa band. In the immunoblotting-inhibition assays, cat serum albumin completely inhibited IgE binding to pork extract. The patient underwent 2 oral food challenges with well-cooked pork and beef, both causing an anaphylactic reaction. The patient's history and in-vivo and in-vitro tests led to a diagnosis of pork-cat syndrome with clinical cross-reactivity to another mammalian serum albumin. This case should stimulate oral food challenges with other well-cooked mammalian meats in patients with this syndrome to establish a tolerance threshold and avoid possible unexpected anaphylactic reactions.

A síndrome gato-porco é rara e ocorre em doentes alérgicos ao pêlo de gato, envolvendo reatividade cruzada entre as albuminas séricas (AS) de gato e de porco. Normalmente, a doença respiratória a pêlo de gato precede a alergia alimentar, sugerindo uma sensibilização primária à albumina sérica de gato. Uma vez que estas proteínas são termolábeis, as reações tendem a ser mais graves com carnes menos cozidas. Mulher de 27 anos com rinoconjuntivite persistente moderada a grave desde a infância que refere duas reações imediatas mucocutâneas após ingestão de pequenas quantidades de carne de porco. Os testes cutâneos por picada com extratos comerciais mostraram sensibilização à carne de porco e os testes prick-to-prick confirmaram sensibilização à carne de porco e de vaca cruas. A IgE específica (sIgE) foi positiva para carne de porco, e o ensaio ISAC mostrou sensibilização a Fel d 2. Foram realizados ensaios de immunoblotting SDS-PAGE IgE com extratos de carne de porco crua e cozidas que detectaram uma banda de 60 kDA. Nos ensaios de inibição por immunoblotting a albumina sérica de gato produziu uma inibição total da ligação da IgE ao extrato de carne de porco. A doente realizou duas provas de provocação oral com carne de porco e de vaca cozidas, ambas positivas com desenvolvimento de reação anafilática. A história clínica, os testes in-vivo e in-vitro levaram ao diagnóstico de síndrome gato-porco com reatividade cruzada clínica a outras albuminas séricas de mamíferos. A síndrome gato-porco é rara e pode causar reações fatais. Este caso frisa a importância da realização de provas de provocação oral com outras carnes de mamíferos bem cozidas em doentes com esta síndrome, de forma a estabelecer um limiar de tolerância e evitar possíveis reações anafiláticas inesperadas.

Proteinuria y síndrome nefrótico / Proteinuria and Nephrotic Syndrome

Introducción: El síndrome nefrótico es una patología que afecta el complejo glomerular del riñón, se caracteriza por una proteinuria mayor 3500 mg/d. De acuerdo a la respuesta de los esteroides se puede clasificar en síndrome nefrótico en esteroide resistente o esteroide sensible. Objetivo: Determinar la relación que existe entre la proteinuria y las variantes del síndrome nefrótico en adultos. Métodos: Se realizó un estudio descriptivo, retrospectivo, tipo serie de casos, con una población de 28 pacientes. Se recolectaron y se procesaron los datos a través del software Epi-Info 7,2TM; la frecuencia simple, la media estadística, prueba t de Student, y el coeficiente de correlación de Pearson. Resultados: En el análisis combinatorio de los fármacos adyuvantes para síndrome nefrótico, el grupo que utilizó antiproteinúricos pero no estatinas, demostró una diferencia estadísticamente significativa entre la proteinuria postratamiento media del grupo de síndrome nefrótico esteroideo resistente (6202 mg/d) vs síndrome nefrótico esteroideo sensible (65,9 mg/d) (valor de p 0,418). Existe una correlación negativa entre los niveles proteinuria postratamiento y el nivel de albúmina sérica postratamiento (r = - 0,7 valor de p < 0,00001). Conclusiones: Se demostró la ausencia de asociación entre la proteinuria inicial y las variantes de síndrome nefrótico esteroide sensible y esteroide resistente (valor de p = 0,8)(AU)

Introduction: Nephrotic syndrome is a pathology that affects the glomerular complex of the kidney, characterized by proteinuria greater than 3500 mg/d. According to the response to steroids, nephrotic syndrome can be classified as steroid-resistant or steroid-sensitive. Objective: To determine the relationship between proteinuria and the variants of the nephrotic syndrome in adults. Methods: A descriptive, retrospective, case series type study was carried out with a population of 28 patients. The data was collected and processed through Epi-Info 7.2TM software; simple frequency, statistical mean, student's t-test, and Pearson's correlation coefficient. Results: The statistically significant difference was obtained in the antiproteinuric and non-statin group, between the mean post-treatment proteinuria of the steroid resistant nephrotic syndrome group (6202 mg/d) in comparison to steroid sensitive nephrotic syndrome (65.9 mg/d) (p value 0.0418). There is negative correlation between post-treatment proteinuria levels and post-treatment serum albumin level (r= -0.7 p value <0.00001). Conclusions: The absence of association between initial proteinuria and steroid-sensitive and steroid-resistant variants of nephrotic syndrome was demonstrated (p value=0.8)(AU)

A Synergistic pH-Responsive Serum Albumin-Based Drug Delivery System Loaded with Doxorubicin and Pentacyclic Triterpene Betulinic Acid for Potential Treatment of NSCLC.

Nanosized drug delivery systems (DDS) have been studied as a novel strategy against cancer due to their potential to simultaneously decrease drug inactivation and systemic toxicity and increase passive and/or active drug accumulation within the tumor(s). Triterpenes are plant-derived compounds with interesting therapeutic properties. Betulinic acid (BeA) is a pentacyclic triterpene that has great cytotoxic activity against different cancer types. Herein, we developed a nanosized protein-based DDS of bovine serum albumin (BSA) as the drug carrier combining two compounds, doxorubicin (Dox) and the triterpene BeA, using an oil-water-like micro-emulsion method. We used spectrophotometric assays to determine protein and drug concentrations in the DDS. The biophysical properties of these DDS were characterized using dynamic light scattering (DLS) and circular dichroism (CD) spectroscopy, confirming nanoparticle (NP) formation and drug loading into the protein structure, respectively. The encapsulation efficiency was 77% for Dox and 18% for BeA. More than 50% of both drugs were released within 24 h at pH 6.8, while less drug was released at pH 7.4 in this period. Co-incubation viability assays of Dox and BeA alone for 24 h demonstrated synergistic cytotoxic activity in the low µM range against non-small-cell lung carcinoma (NSCLC) A549 cells. Viability assays of the BSA-(Dox+BeA) DDS demonstrated a higher synergistic cytotoxic activity than the two drugs with no carrier. Moreover, confocal microscopy analysis confirmed the cellular internalization of the DDS and the accumulation of the Dox in the nucleus. We determined the mechanism of action of the BSA-(Dox+BeA) DDS, confirming S-phase cell cycle arrest, DNA damage, caspase cascade activation, and downregulation of epidermal growth factor receptor (EGFR) expression. This DDS has the potential to synergistically maximize the therapeutic effect of Dox and diminish chemoresistance induced by EGFR expression using a natural triterpene against NSCLC.

Donkey semen cryopreservation: Alternatives with permeable, non-permeable cryoprotectants and seminal plasma.

Cryopreservation of semen is an important technique to preserve genetic material. Yet, pregnancy rates in jennies after artificial insemination with frozen-thawed donkey semen are poor. This condition has been attributed to the impact of permeable cryoprotectants, that could cause high post-breeding endometritis. Removal of seminal plasma (SP) prior to semen freezing process is another contributing factor. SP is involved in a multitude of sperm functions and events preceding fertilization and has a mediating effect of sperm capacitation and postcoital uterine inflammatory response. The aim of this study was to evaluate different alternatives in donkey semen cryopreservation with permeable, non-permeable cryoprotectants, BSA and SP. Thirty ejaculates from 10 donkeys were cryopreserved with different combinations of dimethylformamide (DMF, 5%), sucrose (SUC, 200 mM) and homologous SP (10%): DMF (T1), DMF/SP (T2), SUC/BSA (T3), SUC/BSA/SP (T4), DMF/SUC/BSA (T5), DMF/SUC/BSA/SP (T6), DMF/BSA (T7) and DMF/BSA/SP (T8). After thawing, sperm motility and kinetics were assessed by computerized semen analysis. Sperm vitality (SV) was evaluated by fluorescence microscopy, functional membrane integrity (FMI) by the HOST test, abnormal morphology by eosin-nigrosin staining and sperm membrane stability by flow cytometry. For statistical analysis, sperm quality indexes (SQi) were obtained, general linear models were carried out and mean comparisons were made by the Tukey test. T1, T2, T5, T6, and T7 had higher and equivalent results for motility, most kinetic parameters and function membrane integrity. Cryopreservation of donkey semen without permeable cryoprotectant (T3 and T4) showed a reduction in motility, kinetics, SV, FMI and SQi. T5 showed a reduction in progressive motility, sperm velocities, IMF and SQi compared to other DMF treatments. T6 and T8 achieved higher SQi values compared to T1, but they were not different compared to T2 and T7. T1 had a smaller sperm population with low-M540 compared to T3. It is concluded that the use of permeable cryoprotectant is essential to achieve higher post-thaw quality of donkey semen. In addition, the combined use of BSA, SUC and/or PS may provide additional sperm protection compared to the individual use of DMF.

Protein source in maturation media affects gene expression in cumulus cells and embryo development in cattle.

We aimed to evaluate if protein source (PS) alterations during IVM affect embryo sex/development and gene expression profile in cumulus cells (CCs). Bovine oocytes were matured and cultured in the presence of FBS or BSA. Then, the PS effect during IVM on gene expression (GPC4, VCAN, GHR, PTGS2, and ALCAM) was determined. CC biopsy was removed before and after IVM treatments. After fertilization and cultured, CCs were grouped according to their fate into CCs from immature COCs, CCs from COCs that did or did not result in embryos (according to PS). Results showed that when the culture was performed in FBS presence, blastocyst rate was higher (p < 0.05) than BSA. However, when embryos were cultured with BSA, no effect (p > 0.05) of PS during IVM was observed. PS used during IVM did not affect embryos sex (p > 0.05) but changed VCAN, GHR, PTGS2, and ALCAM genes expression. No differences (p > 0.05) were observed between immature and mature CCs groups in gene expression, regardless of their fate. Only the GHR gene was related to embryo production but just with FBS on IVM. In conclusion, PS can affect embryo development when using the serum on IVM and IVC, influences CCs gene expression, and has to be considered when studying oocyte quality markers.