Structural and functional properties of a high moisture extruded mixture of pea proteins (Pisum sativum), amaranth flour (Amaranthus hypochondriacus), and oat flour (Avena sativa).

Textured vegetable proteins (TVP) are an alternative to meet the increasing demand for non-animal food. This study aimed to develop a TVP from mixtures with 45 % pea protein isolate (PPI) enriched with amaranth (AF) and oat (OF) flours using high-moisture extrusion technology (HME) varying the moisture (50-70 %) and the temperature in the second heating zone of the extruder (110-140 °C). After extrusion, all samples demonstrated higher values of water absorption capacity (WAC) than non-extruded mixtures. Mixture of AF:OF:PPI (40:15:45 %) extruded at 60 % moisture and 135 °C showed promising functional properties with WAC and WSI values of 3.2 ± 0.2 g H2O/g and 24.89 ± 2.31 %, respectively, and oil absorption capacity (OAC) of 1.3 g oil/g. The extrusion process altered the thermal and structural properties of proteins promoting a desirable fibrous structure. This confirms the feasibility of using HME to develop TVP based on PPI, AF, and OF.

Comparative Proteomic Analysis of Wild and Cultivated Amaranth Species Seeds by 2-DE and ESI-MS/MS.

Amaranth is a promising staple food that produces seeds with excellent nutritional quality. Although cultivated species intended for grain production have interesting agronomic traits, relatively little is known about wild species, which can prosper in diverse environments and could be a rich genetic source for crop improvement. This work focuses on the proteomic comparison between the seeds of wild and cultivated amaranth species using polarity-based protein extraction and two-dimensional gel electrophoresis. Differentially accumulated proteins (DAPs) showed changes in granule-bound starch synthases and a wide range of 11S globulin isoforms. The electrophoretic profile of these proteins suggests that they may contain significant phosphorylation as post-translational modifications (PTMs), which were confirmed via immunodetection. These PTMs may impact the physicochemical functionality of storage proteins, with potential implications for seed agronomic traits and food system applications. Low-abundant DAPs with highly variable accumulation patterns are also discussed; these were involved in diverse molecular processes, such as genic regulation, lipid storage, and stress response.

In silico and in vitro study of FLT3 inhibitors and their application in acute myeloid leukemia.

Acute myeloid leukemia (AML) is the most common hematological cancer in the adult population worldwide. Approximately 35% of patients with AML present internal tandem duplication (ITD) mutations in the FMS­like tyrosine kinase 3 (FLT3) receptor associated with poor prognosis, and thus, this receptor is a relevant target for potential therapeutics. Tyrosine kinase inhibitors (TKIs) are used to treat AML; however, their molecular interactions and effects on leukemic cells are poorly understood. The present study aimed to gain insights into the molecular interactions and affinity forces of four TKI drugs (sorafenib, midostaurin, gilteritinib and quizartinib) with the wild­type (WT)­FLT3 and ITD­mutated (ITD­FLT3) structural models of FLT3, in its inactive aspartic acid­phenylalanine­glycine motif (DFG­out) and active aspartic acid­phenylalanine­glycine motif (DFG­in) conformations. Furthermore, the present study evaluated the effects of the second­generation TKIs gilteritinib and quizartinib on cancer cell viability, apoptosis and proliferation in the MV4­11 (ITD­FLT3) and HL60 (WT­FLT3) AML cell lines. Peripheral blood mononuclear cells (PBMCs) from a healthy volunteer were included as an FLT3­negative group. Molecular docking analysis indicated higher affinities of second­generation TKIs for WT­FLT3/DFG­out and WT­FLT3/DFG­in compared with those of the first­generation TKIs. However, the ITD mutation changed the affinity of all TKIs. The in vitro data supported the in silico predictions: MV4­11 cells presented high selective sensibility to gilteritinib and quizartinib compared with the HL60 cells, whereas the drugs had no effect on PBMCs. Thus, the current study presented novel information about molecular interactions between the FLT3 receptors (WT or ITD­mutated) and some of their inhibitors. It also paves the way for the search for novel inhibitory molecules with potential use against AML.

Unraveling cell wall polysaccharides during blueberry ripening: insights into the roles of rhamnogalacturonan-I and arabinogalactan proteins in fruit firmness.

Blueberries (Vaccinium corymbosum) undergo significant texture changes during development and ripening, notably a consistent decrease in firmness, which affects fruit quality, consumer preference, transportability, and shelf life. This study examined the composition and structural modifications of the cell wall in five commercially available blueberry varieties with differing firmness levels at harvest. Our approach integrated various biochemical techniques for a comprehensive analysis of cell wall components to elucidate firmness differences at the harvest stage. One of the conclusions was the relationship between a low degree of pectin methylesterification and the presence of increased egg-box structures, which correlated with increased firmness. The data suggest that low-abundance pectins in blueberry cell walls, such as rhamnogalacturonan-I participate in firmness modulation through their side branches or by linking to arabinogalactan proteins. Additionally, the xyloglucan structure can be one of the determinants of fruit firmness. Although, this work provides a broad insight into the relationship between cell wall composition and firmness in blueberry, a more detailed analysis, specifically focusing on pectin and hemicelluloses, would be of significant value.

IMP3, CDK4, MDM2 and ß-catenin expression in Enchondroma and Central Chondrosarcoma: Diagnostic and prognostic utility.

INTRODUCTION: The role of IMP3, CDK4, MDM2 and ß-catenin proteins in Enchondroma and Central Chondrosarcoma is not totally understood. The aim of this study is to evaluate the immunoexpression of these proteins, associating histological grade, clinical data and prognosis to these tumors. METHODS: This is a retrospective-analytical study of 32 Enchondroma and 70 Central Chondrosarcoma. RESULTS: IMP3, CDK4, MDM2 and ß-catenin expression was observed in 22.82 %, 13.82 %, 17.17 % and in 8.8 % of cases, respectively. All Enchondromas positive for these immunomarkers were located in short tubular bones. The positivity for these antibodies is directly proportional to Chondrosarcoma's histological grade increase. No difference was found between Enchondroma and Chondrosarcoma, Grade 1 for IMP3, CDK4 and ß-catenin positivity. Significant metastasis outcome was observed for IMP3, CDK4, MDM2 and death for MDM2 expression. CONCLUSION: IMP3, CDK4, MDM2 and ß-catenin expression in Enchondromas of short bones phenotypically characterizes these tumors. Their expression has not proven to be useful either as diagnostic markers of these neoplasms or in distinguishing between Enchondroma and Chondrosarcoma, Grade 1. The significant immunoexpression of IMP3, CDK4 and MDM2 in metastatic Chondrosarcoma and the lower survival in those with positivity for MDM2 suggest a possible association of these proteins with tumor aggressiveness.

The Modulation of Septic Shock: A Proteomic Approach.

Sepsis poses a significant challenge due its lethality, involving multiple organ dysfunction and impaired immune responses. Among several factors affecting sepsis, monocytes play a crucial role; however, their phenotype, proteomic profile, and function in septic shock remain unclear. Our aim was to fully characterize the subpopulations and proteomic profiles of monocytes seen in septic shock cases and discuss their possible impact on the disease. Peripheral blood monocyte subpopulations were phenotype based on CD14/CD16 expression by flow cytometry, and proteins were extracted from the monocytes of individuals with septic shock and healthy controls to identify changes in the global protein expression in these cells. Analysis using 2D-nanoUPLC-UDMSE identified 67 differentially expressed proteins in shock patients compared to controls, in which 44 were upregulated and 23 downregulated. These proteins are involved in monocyte reprogramming, immune dysfunction, severe hypotension, hypo-responsiveness to vasoconstrictors, vasodilation, endothelial dysfunction, vascular injury, and blood clotting, elucidating the disease severity and therapeutic challenges of septic shock. This study identified critical biological targets in monocytes that could serve as potential biomarkers for the diagnosis, prognosis, and treatment of septic shock, providing new insights into the pathophysiology of the disease.

Codon Optimization is Required to Express Fluorogenic Reporter Proteins in Lactococcus lactis.

Lactococcus lactis is a Gram-positive bacterium used to produce fermented foods and heterologous proteins. Its Nisin-controlled gene expression system stands out for its versatility and safety. However, the lower GC content in its genome may lead to some limitations in protein production. In this study, we explored the importance and effect of codon optimization on fluorescent reporter protein expression in L. lactis. Three non-optimized fluorescent reporter genes (gfp, rfp, and mcherry) were compared to the codon-optimized variant (mcherry-O). Parameters such as Codon Adaptation Index (CAI), Effective Number of Codons (Enc) and Guanine-Cytosine percentage (% GC) were determined to assess their influence on gene expression and protein synthesis. The production of non-optimized fluorescent proteins does not correlate with their gene expression levels, except for the codon-optimized mCherry-O protein, which was detected in the SDS-PAGE gel and the extracted lysate (visually detected). Expression of the mcherry gene was similar to the mcherry-O gene, but protein was only detected with the optimized gene. The gfp gene showed the highest expression levels, but the quantity of protein was undetectable by SDS-PAGE. The rfp gene was revealed to be an optimized gene but not tailored for L. lactis. These findings underscore the necessity of comprehensive codon optimization for foreign genes in L. lactis and reveal intriguing complexities between expression levels, RNA stability and protein synthesis.

A contact-based analysis of local energetic frustration dynamics identifies key residues enabling RfaH fold-switch.

Fold-switching enables metamorphic proteins to reversibly interconvert between two highly dissimilar native states to regulate their protein functions. While about 100 proteins have been identified to undergo fold-switching, unveiling the key residues behind this mechanism for each protein remains challenging. Reasoning that fold-switching in proteins is driven by dynamic changes in local energetic frustration, we combined fold-switching simulations generated using simplified structure-based models with frustration analysis to identify key residues involved in this process based on the change in the density of minimally frustrated contacts during refolding. Using this approach to analyze the fold-switch of the bacterial transcription factor RfaH, we identified 20 residues that significantly change their frustration during its fold-switch, some of which have been experimentally and computationally reported in previous works. Our approach, which we developed as an additional module for the FrustratometeR package, highlights the role of local frustration dynamics in protein fold-switching and offers a robust tool to enhance our understanding of other proteins with significant conformational shifts.

Untangling Zebrafish Genetic Annotation: Addressing Complexities and Nomenclature Issues in Orthologous Evaluation of TCOF1 and NOLC1.

Treacher Collins syndrome (TCS) is a genetic disorder affecting facial development, primarily caused by mutations in the TCOF1 gene. TCOF1, along with NOLC1, play important roles in ribosomal RNA transcription and processing. Previously, a zebrafish model of TCS successfully recapitulated the main characteristics of the syndrome by knocking down the expression of a gene on chromosome 13 (coding for Uniprot ID B8JIY2), which was identified as the TCOF1 orthologue. However, database updates renamed this gene as nolc1 and the zebrafish database (ZFIN) identified a different gene on chromosome 14 as the TCOF1 orthologue (coding for Uniprot ID E7F9D9). NOLC1 and TCOF1 are large proteins with unstructured regions and repetitive sequences that complicate alignments and comparisons. Also, the additional whole genome duplication of teleosts sets further difficulty. In this study, we present evidence that endorses that NOLC1 and TCOF1 are paralogs, and that the zebrafish gene on chromosome 14 is a low-complexity LisH domain-containing factor that displays homology to NOLC1 but lacks essential sequence features to accomplish TCOF1 nucleolar functions. Our analysis also supports the idea that zebrafish, as has been suggested for other non-tetrapod vertebrates, lack the TCOF1 gene that is associated with tripartite nucleolus. Using BLAST searches in a group of teleost genomes, we identified fish-specific sequences similar to E7F9D9 zebrafish protein. We propose naming them "LisH-containing Low Complexity Proteins" (LLCP). Interestingly, the gene on chromosome 13 (nolc1) displays the sequence features, developmental expression patterns, and phenotypic impact of depletion that are characteristic of TCOF1 functions. These findings suggest that in teleost fish, the nucleolar functions described for both NOLC1 and TCOF1 mediated by their repeated motifs, are carried out by a single gene, nolc1. Our study, which is mainly based on computational tools available as free web-based algorithms, could help to solve similar conflicts regarding gene orthology in zebrafish.

The survivin/XIAP suppressant YM155 impairs clonal growth and induces apoptosis in JAK2V617F cells.

The central role of the control of apoptosis in the pathophysiology of Philadelphia chromosome-negative myeloproliferative neoplasms has recently been reinforced in genetic and pharmacological studies. The inhibitor of apoptosis protein family has eight members and plays an important role in apoptosis, with the most studied being survivin (BIRC5) and X-linked inhibitor of apoptosis (XIAP). YM155 is a small molecule with antineoplastic potential that has been described as a suppressant of survivin and XIAP. In the present study, BIRC5 expression was significantly increased in primary myelofibrosis patients compared to healthy donors. On the other hand, XIAP expression was reduced in myeloproliferative neoplasms patients. In JAK2V617F cells, YM155 reduces cell viability and autonomous clonal growth and induces apoptosis, cell cycle arrest, and autophagy. HEL cells that show greater malignancy are more sensitive to the drug than SET2 cells. In the molecular scenario, YM155 modulates apoptosis-, cell cycle-, DNA damage- and autophagy-related genes. Protein expression analysis corroborates the observed cellular phenotype and exploratory gene expression findings. In summary, our results indicate that survivin/BIRC5 and XIAP are differently expressed in myeloproliferative neoplasms and YM155 has multiple antineoplastic effects on JAK2V617F cells suggesting that inhibitor of apoptosis proteins may be a target for pharmacological interventions in the treatment of these diseases.

Plant Defensin PgD1 a Biotechnological Alternative Against Plant Pathogens.

Plant defensins are small antimicrobial proteins (AMP) that participate in the immune defense of plants through their antibacterial, antiviral and antifungal activities. PgD1 is a defensin from Picea glauca (Canadian Pine) and has antifungal activity against plant pathogens. This activity positions it as an alternative biotechnological agent to pesticides commonly used against these plant fungi diseases. The present study aimed to recombinantly produce PgD1 in Escherichia coli to characterize its in vitro antifungal potential against different phytopathogens. To achieve this, the coding gene was amplified and cloned into pET30a( +). Recombinant plasmid was subsequently introduced into E. coli for the soluble expression of defensin PgD1. To evaluate the antifungal activity of the expressed protein, the growth inhibition test was used in solid and liquid media for approximately 7 days against significant plant pathogens, that cause significant crop damage including: Botrytis cinerea, Colletotrichum gloeosporioides, Colletotrichum musae, Colletotrichum graminicola and Fusarium oxysporum. Additionally, stability assessments included temperature variation experiments and inhibition tests using dithiothreitol (DTT). The results showed that there was significant inhibition of the fungal species tested when in the presence of PgD1. Furthermore, defensin proved to be resistant to temperature variations and demonstrated that part of its stability is due to its primary structure rich in cysteine ​​residues through the denaturation test with dithiothreitol (DTT) where the antifungal activity of PgD1 defensin was inhibited. These data indicate that recombinant PgD1 could be utilized as a plant protection technology in agriculture.

In silico comparative analysis of cestode and human NPC1 provides insights for ezetimibe repurposing to visceral cestodiases treatment.

Visceral cestodiases, like cysticercoses and echinococcoses, are caused by cystic larvae from parasites of the Cestoda class and are endemic or hyperendemic in many areas of the world. Current therapeutic approaches for these diseases are complex and present limitations and risks. Therefore, new safer and more effective treatments are urgently needed. The Niemann-Pick C1 (NPC1) protein is a cholesterol transporter that, based on genomic data, would be the solely responsible for cholesterol uptake in cestodes. Considering that human NPC1L1 is a known target of ezetimibe, used in the treatment of hypercholesterolemia, it has the potential for repurposing for the treatment of visceral cestodiases. Here, phylogenetic, selective pressure and structural in silico analyses were carried out to assess NPC1 evolutive and structural conservation, especially between cestode and human orthologs. Two NPC1 orthologs were identified in cestode species (NPC1A and NPC1B), which likely underwent functional divergence, leading to the loss of cholesterol transport capacity in NPC1A. Comparative interaction analyses performed by molecular docking of ezetimibe with human NPC1L1 and cestode NPC1B pointed out to similarities that consolidate the idea of cestode NPC1B as a target for the repurposing of ezetimibe as a drug for the treatment of visceral cestodiases.

Physiology, Pathophysiology and Clinical Relevance of D-Amino Acids Dynamics: From Neurochemistry to Pharmacotherapy.

Over three decades ago, two independent groups of investigators identified free D-aspartic and later D-serine in specific brain nuclei and endocrine glands. This finding revealed a novel, non-proteinogenic role of these molecules. Moreover, the finding that aged proteins from the human eye crystallin, teeth, bone, blood vessels or the brain incorporate D-aspartic acids to specific primary protein sequences fostered the hypothesis that aging might be related to D-amino acid isomerization of body proteins. The experimental confirmation that schizophrenia and neurodegenerative diseases modify plasma free D-amino acids or tissue levelsnurtured the opportunity of using D-amino acids as therapeutic agents for several disease treatments, a strategy that prompted the successful current application of D-amino acids to human medicine.

Identification of dystrophin Dp71dΔ71-associated proteins in PC12 cells by quantitative proteomics.

Dystrophin Dp71 is essential for the development of the nervous system. Its alteration is associated with intellectual disability. Different Dp71 isoforms are generated by alternative splicing; however, their functions have not been fully described. Here, we identified Dp71dΔ71-associated proteins to understand the complex functions. PC12 cells, stably transfected with pTRE2pur-Myc/Dp71dΔ71 or pTRE2pur-Myc empty vector (EV), were analyzed by immunoprecipitation followed with quantitative proteomics with data-independent acquisition and ion mobility separation. We used the Top3 method to quantify absolutely every protein detected. A total of 106 proteins were quantified with Progenesis QI software and the database UP000002494. Seven new proteins associated with Dp71dΔ71 were selected with at least 2-fold quantity between immunoprecipitated proteins of PC12-Myc/Dp71dΔ71 versus PC12-EV cells. These results revealed new proteins that interact with Dp71dΔ71, including ß-Tubulin, S-adenosylmethionine synthase isoform type-2, adapter molecule crk, helicase with zinc finger 2, WD repeat domain 93, cyclin-L2 and myosin-10, which are related to cell migration and/or cell growth. The results lay the foundation for future research on the relationship between these proteins and Dp71 isoforms.

Identification of potential new T cell activation molecules: a Bioinformatic Approach.

T-cell activation is central for the initiation of T cell mediated adaptive immune response and is the result of the close communication between the Antigen Presenting Cell (APC) and the T lymphocyte. Although T-cell activation is currently well understood, and many intracellular pathways are well characterized, nevertheless new players are constantly identified, and this complements the known protein interactome. In this work we aimed to identify new proteins involved in T cell activation. We reviewed and analyzed results of microarray gene expression datasets reported in the public database GEO-NCBI. Using data from GSE136625, GSE50971, GSE13887, GSE11989 and GSE902 we performed different comparisons using R and other bioinformatic tools including GEO2R and we report here upregulated genes that have no previous reports in immune related functions and with potential participation upon T-cell activation. Our results indicate that RND3, SYT10, IgSF6 and PIN1 are potential new T-cell activation molecules.

Physiological Stimulus for the Synthesis of Basement Membrane Proteins Leading to Its Reconstruction.

The aim of the present study was to report the remodeling of the basement membrane through physiological stimulus during the treatment of fibrosis in a lower limb with lymphedema. A clinical trial was conducted involving the evaluation of the basement membrane in skin biopsies before and after treatment for clinical stage II lower limb lymphedema using the Godoy method for the reversal of lymphedema and skin fibrosis. The samples were stained with Gomori's reticulin stain and evaluated using Weibel's multipoint morphometric method at the Godoy Clinic. Prior to treatment for lymphedema, rupture and important discontinuity of the basement membrane was found. After treatment, structural continuity and thickness had returned to the regions of previous rupture. The difference was statistically significant (P < 0.05, paired t-test). The present study reports that physiological stimuli targeting the lymphatic system led to the clinical reversal of fibrosis, as well as stimulate the synthesis of extracellular matrix proteins and the reconstruction of the basal lamina of the skin.

Use of recombinant proteins for the diagnosis and prevention of Mycoplasma bovis: a systematic review.

Introduction: Mycoplasma bovis is a highly contagious pathogen that causes various diseases in herd animals, negatively impacting reproduction, production, and milk yield. Effective diagnostic methods and vaccine development are critical for controlling M. bovis outbreaks. This systematic review aimed to evaluate diagnostic alternatives and vaccine compounds based on recombinant proteins. Methods: Following the PRISMA protocol, a systematic search was conducted in the SciELO, PubMed, and CAPES Periodicals Portal databases. Inclusion criteria included studies published between 2008 and 2023 that involved (1) the use of recombinant proteins for M. bovis identification or vaccine production, (2) biological samples, (3) availability in the selected databases, (4) in vitro or in vivo experimental designs, and (5) English-language publications. Results: Ten of the initial 53 studies screened met the inclusion criteria. Of these, four studies focused on diagnostic approaches and six on vaccine development. Diagnostic studies predominantly used an indirect enzyme-linked immunosorbent assay (ELISA) with recombinant proteins, achieving over 90% sensitivity and specificity in detecting M. bovis infections. In contrast, the development of recombinant vaccines has shown limited success, with challenges in identifying effective adjuvants and optimizing conditions for protective immunity. Discussion: While recombinant protein-based diagnostics have proven effective, developing a successful vaccine against M. bovis remains elusive. Further research is necessary to refine vaccine formulations, including selecting suitable adjuvants and challenge models to enhance protective efficacy against M. bovis infections.

Effect of Integrated Extraction Techniques on the Technofunctional and Bioactive Properties of Brosimum alicastrum Swartz Proteins.

This study addresses the need for effective protein extraction and characterization to unlock the potential of underutilized plant resources like Brosimum alicastrum Swartz nuts, aiming to enhance their value as functional ingredients in food applications. Extraction methods, including pH modulation, ultrasound-assisted extraction, and enzymatic hydrolysis, are employed to enhance technofunctional and bioactive properties. The protein extracts are evaluated for solubility, emulsifying capacity, foaming properties, and water/oil-holding capacities to assess their technofunctional potential. Additionally, the bioactive properties, such as antioxidant and anti-inflammatory activities, are analyzed to explore potential health benefits. The results demonstrate that integrated extraction techniques significantly improve the yield and quality of Brosimum alicastrum Swartz nut proteins. Enzymatic hydrolysis, in particular, produces hydrolysates with superior bioactive properties. These findings highlight the potential of Brosimum alicastrum Swartz proteins as valuable ingredients for the food and pharmaceutical industries, promoting the utilization of underexploited plant resources for sustainable and health-promoting applications.

Exploration of the Binding Site of Arachidonic Acid in gp63 of Leishmania mexicana and in Orthologous Proteins in Clinically Important Parasites.

Recently, we published that the monoclonal antibody (D12 mAb) recognizes gp63 of L. mexicana, and it is responsible for COX activity. This D12 mAb exhibited cross-reactivity with Trypanosoma cruzi, Entamoeba histolytica, Acanthamoeba castellanii, and Naegleria fowleri. COX activity assays performed in these parasites suggested the potential presence of such enzymatic activity. In our investigation, we confirmed that wild-type recombinant gp63 exhibits COX-like activity, in contrast to a mutated recombinant gp63 variant. Consequently, our objective was to identify sequences orthologous to gp63 and subsequently analyze the binding of arachidonic acid (AA) to the putative active sites of these proteins. Given the absence of a crystallized structure for this protein in the Protein Data Bank (PDB), it was imperative to first obtain a three-dimensional structure by homology modeling, using leishmanolysin from Leishmania major (PDB ID: LML1) as a template in the Swiss model database. The results obtained through molecular docking simulations revealed the primary interactions of AA close to the Zinc atom present in the catalytic site of gp63-like molecules of several parasites, predominantly mediated by hydrogen bonds with HIS264, HIS268 and HIS334. Furthermore, COX activity was evaluated in commensal species such as E. dispar and during the encystment process of E. invadens.

Pérdida de proteínas en líquido peritoneal de pacientes críticos con abdomen abierto / Protein loss in peritoneal fluid of critically ill patients with open abdomen

Introducción. Los pacientes con patología abdominal quirúrgica que requieren manejo con abdomen abierto son susceptibles a la pérdida de proteínas desde la cavidad expuesta. El objetivo de este estudio fue caracterizar la pérdida proteica a través de dos tipos de cierre temporal abdominal. Métodos. Se realizó un estudio decohorte prospectivo, con pacientes críticos manejados durante el año 2021 con abdomen abierto mediante dos tipos de cierre temporal: bolsa de Bogotá y ABThera™. Se recolectaron muestras intraoperatorias seriadas de líquido peritoneal (días 1, 3 y 5). Se calcularon frecuencias y promedios, y se compararon con las pruebas de Chi cuadrado y t de Student. Resultados. Se incluyeron 25 pacientes. El promedio de pérdida de proteínas en líquido peritoneal fue mayor con el sistema ABThera™ (44,38 g/L) comparado con la bolsa de Bogotá (25,18 g/L; p=0,0185). Durante el seguimiento se observó la tendencia a la disminución del promedio de proteínas perdidas por ambos sistemas, pero con ABThera™ se perdieron en promedio 15,47 gr/L más de proteínas, independientemente del estado nutricional y del aporte proteico recibido (p=0,042). No hubo diferencias según la etiología que llevó al manejo con abdomen abierto, los procedimientos quirúrgicos realizados o el estado de infección por COVID-19. Conclusiones. El abdomen abierto representa una fuente importante de pérdida de proteínas, que es diferente según el tipo de cierre temporal usado. Estas pérdidas deberían considerarse en los cálculos de soporte nutricional en la unidad de cuidado intensivo.

Introduction. Patients with surgical abdominal pathology requiring management with an open abdomen are susceptible to protein loss from the exposed cavity. The objective of this study was to characterize protein loss through two types of temporary abdominal closure. Methods. A prospective cohort study was carried out with critically ill patients managed during 2021 with an open abdomen using two types of temporary closure: Bogota bag and ABThera™. Serial intraoperative peritoneal fluid samples were collected (days 1, 3, and 5). Frequencies and averages were calculated and compared with the Chi square and Student's t tests. Results. Twenty-five patients were included. The average protein loss in peritoneal fluid was higher with the ABThera™ system (44.38 g/L) compared to the Bogota bag (25.18 g/L; p-value=0.0185). During follow-up, a tendency to decrease the average protein lost by both systems was observed, but with ABThera™ an average of 15.47 gr/L more protein was lost, regardless of the nutritional status and protein intake received (p=0.042). There were no differences based on etiology leading to open abdomen management, surgical procedures performed, or Covid-19 infection status. Conclusions. The open abdomen represents an important source of protein loss, which is different depending on the type of temporary closure used. These losses should be considered in calculations of nutritional support in the intensive care unit.