Sex and Gender-related Disparities in Clinical Characteristics and Outcomes in Heart Transplantation.

PURPOSE OF REVIEW: Limited research has been conducted on sex disparities in heart transplant (HT). The aim of this review is to analyse the available evidence on the influence of sex and gender-related determinants in the entire HT process, as well as to identify areas for further investigation. RECENT FINDINGS: Although women make up half of the population affected by heart failure and related mortality, they account for less than a third of HT recipients. Reasons for this inequality include differences in disease course, psychosocial factors, concerns about allosensitisation, and selection or referral bias in female patients. Women are more often listed for HT due to non-ischaemic cardiomyopathy and have a lower burden of cardiovascular risk factors. Although long-term prognosis appears to be similar for both sexes, there are significant disparities in post-HT morbidity and causes of mortality (noting a higher incidence of rejection in women and of malignancy and cardiac allograft vasculopathy in men). Additional research is required to gain a better understanding of the reasons behind gender disparities in eligibility and outcomes following HT. This would enable the fair allocation of resources and enhance patient care.

Biobased Composites of Poly(Lactic Acid) Melt Compounded with Bacterial and Vegetal Nanocelluloses Incorporated through Different Strategies.

In the current contribution, bacterial nanocellulose obtained from a by-product of Kombucha tea production and vegetal nanocellulose isolated from milled rice husks were employed as fillers of PLA-based composites prepared by intensive mixing followed by compression molding. Given the challenges associated with the incorporation of nanocelluloses-initially obtained as aqueous suspensions-into melt compounding processes, and also with achieving a proper dispersion of the hydrophilic nanofillers within PLA, three different nanofibrils incorporation strategies were studied: i.e., direct mixing of dried milled nanocelluloses and PLA; masterbatching by solvent casting of native nanocelluloses followed by melt compounding; and masterbatching by solvent casting of acetylated nanocelluloses followed by melt compounding. Composites with varying filler content (from 0.5 wt.% to 7 wt.%) were characterized in terms of morphology, optical properties, and mechanical performance. Results revealed the relative suitability of each strategy employed to promote nanocelluloses dispersion within the PLA matrix. PLA/nanocellulose masterbatches prepared by solvent casting proved to be particularly useful for feeding the nanocelluloses into the processing equipment in a dry state with limited hornification. Acetylation also contributed to a better dispersion of both nanocelluloses within the PLA matrix, although no clear positive impact on the mechanical properties of the films was observed. Finally, filler loading played an important role in the films' properties by increasing their stiffness while reducing their translucency.

De Novo Donor-Specific Antibodies after Heart Transplantation: A Comprehensive Guide for Clinicians.

Antibodies directed against donor-specific human leukocyte antigens (HLAs) can be detected de novo after heart transplantation and play a key role in long-term survival. De novo donor-specific antibodies (dnDSAs) have been associated with cardiac allograft vasculopathy, antibody-mediated rejection, and mortality. Advances in detection methods and international guideline recommendations have encouraged the adoption of screening protocols among heart transplant units. However, there is still a lack of consensus about the correct course of action after dnDSA detection. Treatment is usually started when antibody-mediated rejection is present; however, some dnDSAs appear years before graft failure is detected, and at this point, damage may be irreversible. In particular, class II, anti-HLA-DQ, complement binding, and persistent dnDSAs have been associated with worse outcomes. Growing evidence points towards a more aggressive management of dnDSA. For that purpose, better diagnostic tools are needed in order to identify subclinical graft injury. Cardiac magnetic resonance, strain techniques, or coronary physiology parameters could provide valuable information to identify patients at risk. Treatment of dnDSA usually involves plasmapheresis, intravenous immunoglobulin, immunoadsorption, and ritxumab, but the benefit of these therapies is still controversial. Future efforts should focus on establishing effective treatment protocols in order to improve long-term survival of heart transplant recipients.

Impacto de la fracción de eyección del ventrículo izquierdo en el consumo de recursos, los costes y el pronóstico en pacientes con insuficiencia cardiaca / Differences in clinical outcomes, health care resource utilization and costs in heart failure patients according to left ventricular ejection fraction

Introducción y objetivos: No se conoce bien el impacto de la fracción de eyección del ventrículo izquierdo (FEVI) en el coste y la utilización de recursos sanitarios (URS) en la insuficiencia cardiaca (IC). El objetivo de nuestro trabajo es comparar el consumo de costes, la URS y el pronóstico según grupos de FEVI. Métodos: Estudio observacional retrospectivo que incluyó a todos los pacientes con diagnóstico principal de IC en urgencias o en una hospitalización en un centro terciario español durante 2018. Se excluyó la IC de nuevo diagnóstico. Se compararon los resultados clínicos, los costes y la URS según la FEVI (reducida [IC-FEr], ligeramente reducida [IC-FElr] y conservada [IC-FEc]) a 1 año. Resultados: De 1.287 pacientes con diagnóstico de IC en urgencias, 365 (28,4%) fueron dados de alta (grupo de urgencias [GU]) y 919 (71,4%), hospitalizados (GH). En total, 190 pacientes (14,7%) tenían IC-FEr; 146 (11,4%), IC-FElr y 951 (73,9%), IC-FEc. La media de edad fue 80,1±10,7 años, y el 57,1% eran mujeres. La mediana [intervalo intercuartílico] del coste por paciente-año fue de 1.889 [259-6.269] euros en el GU y 5.008 [2.747-9.589] euros en el GH (p <0,001). Los pacientes con IC-FEr del GU sufrieron más hospitalizaciones. El coste de la IC-FEr por paciente-año fue superior en ambos grupos: en el GU, 4.763 [2.076-17.155] euros con IC-FEr frente a 3.900 [590-8.013] euros con IC-FElr frente a 3.812 [259-5.486] euros con IC-FEc; en el GH, 6.321 [3.335-796] frente a 6.170 [3.189-10.484] frente a 4.636 [2.609-8.977] euros respectivamente; todos, p <0,001). Esta diferencia se debió a que los pacientes con IC-FEr ingresaron con mayor frecuencia en unidades de cuidados críticos y recibieron más pruebas diagnóstico-terapéuticas. Conclusiones: La FEVI influye significativamente en los costes y URS en la IC. Los pacientes con IC-FEr, especialmente los hospitalizados, concentran un mayor coste que aquellos con IC-FEc.(AU)

Introduction and objectives: The impact of left ventricular ejection fraction (LVEF) on health care resource utilization (HCRU) and cost in heart failure (HF) patients is not well known. We aimed to compare outcomes, HCRUs and costs according to LVEF groups. Methods: Retrospective, observational study of all patients with an emergency department (ED) visit or admission to a tertiary hospital in Spain 2018 with a primary HF diagnosis. We excluded patients with newly diagnosed heart failure. One-year clinical outcomes, costs and HCRUs were compared according to LVEF (reduced [HFrEF], mildly reduced [HFmrEF], and preserved [HFpEF]). Results: Among 1287 patients with a primary diagnosis of HF in the ED, 365 (28.4%) were discharged to home (ED group), and 919 (71.4%) were hospitalized (hospital group [HG]). In total, 190 patients (14.7%) had HFrEF, 146 (11.4%) HFmrEF, and 951 (73.9%) HFpEF. The mean age was 80.1±10.7 years; 57.1% were female. The median [interquartile range] of costs per patient/y was €1889 [259-6269] in the ED group and €5008 [2747-9589] in the HG (P <.001). Hospitalization rates were higher in patients with HFrEF in the ED group. The median costs of HFrEF per patient/y were higher in patients in both groups: €4763 [2076-17 155] vs €3900 [590-8013] for HFmrEF vs €3812 [259-5486] for HFpEF in the ED group, and €6321 [3335-796] vs €6170 [3189-10484] vs €4636 [2609-8977], respectively, in the hospital group (all P <.001). This difference was driven by the more frequent admission to intensive care units, and greater use of diagnostic and therapeutic tests among HFrEF patients. Conclusions: In HF, LVEF significantly impacts costs and HCRU. Costs were higher in patients with HFrEF, especially those requiring hospitalization, than in those with HFpEF.(AU)

Differences in clinical outcomes, health care resource utilization and costs in heart failure patients according to left ventricular ejection fraction.

INTRODUCTION AND OBJECTIVES: The impact of left ventricular ejection fraction (LVEF) on health care resource utilization (HCRU) and cost in heart failure (HF) patients is not well known. We aimed to compare outcomes, HCRUs and costs according to LVEF groups. METHODS: Retrospective, observational study of all patients with an emergency department (ED) visit or admission to a tertiary hospital in Spain 2018 with a primary HF diagnosis. We excluded patients with newly diagnosed heart failure. One-year clinical outcomes, costs and HCRUs were compared according to LVEF (reduced [HFrEF], mildly reduced [HFmrEF], and preserved [HFpEF]). RESULTS: Among 1287 patients with a primary diagnosis of HF in the ED, 365 (28.4%) were discharged to home (ED group), and 919 (71.4%) were hospitalized (hospital group [HG]). In total, 190 patients (14.7%) had HFrEF, 146 (11.4%) HFmrEF, and 951 (73.9%) HFpEF. The mean age was 80.1±10.7 years; 57.1% were female. The median [interquartile range] of costs per patient/y was €1889 [259-6269] in the ED group and €5008 [2747-9589] in the HG (P <.001). Hospitalization rates were higher in patients with HFrEF in the ED group. The median costs of HFrEF per patient/y were higher in patients in both groups: €4763 [2076-17 155] vs €3900 [590-8013] for HFmrEF vs €3812 [259-5486] for HFpEF in the ED group, and €6321 [3335-796] vs €6170 [3189-10484] vs €4636 [2609-8977], respectively, in the hospital group (all P <.001). This difference was driven by the more frequent admission to intensive care units, and greater use of diagnostic and therapeutic tests among HFrEF patients. CONCLUSIONS: In HF, LVEF significantly impacts costs and HCRU. Costs were higher in patients with HFrEF, especially those requiring hospitalization, than in those with HFpEF.

Validation of N Protein Antibodies to Diagnose Previous SARS-CoV-2 Infection in a Large Cohort of Healthcare Workers: Use of Roche Elecsys® Immunoassay in the S Protein Vaccination Era.

The aim of this study was to validate the detection of anti-nucleocapsid protein (N protein) antibodies for the diagnosis of SARS-CoV-2 infection in light of the fact that most COVID-19 vaccines use the spike (S) protein as the antigen. Here, 3550 healthcare workers (HCWs) were enrolled from May 2020 (when no S protein vaccines were available). We defined SARS-CoV-2 infection if HCWs were found to be positive by RT-PCR or found to be positive in at least two different serological immunoassays. Serum samples from Biobanc I3PT-CERCA were analyzed by Roche Elecsys® (N protein) and Vircell IgG (N and S proteins) immunoassays. Discordant samples were reanalyzed with other commercial immunoassays. Roche Elecsys® showed the positivity of 539 (15.2%) HCWs, 664 (18.7%) were found to be positive by Vircell IgG immunoassays, and 164 samples (4.6%) showed discrepant results. According to our SARS-CoV-2 infection criteria, 563 HCWs had SARS-CoV-2 infection. The Roche Elecsys® immunoassay has a sensitivity, specificity, accuracy, and concordance with the presence of infection of 94.7%, 99.8%, 99.3%, and 0.96, respectively. Similar results were observed in a validation cohort of vaccinated HCWs. We conclude that the Roche Elecsys® SARS-CoV-2 N protein immunoassay demonstrated good performance in diagnosing previous SARS-CoV-2 infection in a large cohort of HCWs.

Biomarker candidates for progression and clinical management of COVID-19 associated pneumonia at time of admission.

COVID-19 pathophysiology is currently not fully understood, reliable prognostic factors remain elusive, and few specific therapeutic strategies have been proposed. In this scenario, availability of biomarkers is a priority. MS-based Proteomics techniques were used to profile the proteome of 81 plasma samples extracted in four consecutive days from 23 hospitalized COVID-19 associated pneumonia patients. Samples from 10 subjects that reached a critical condition during their hospital stay and 10 matched non-severe controls were drawn before the administration of any COVID-19 specific treatment and used to identify potential biomarkers of COVID-19 prognosis. Additionally, we compared the proteome of five patients before and after glucocorticoids and tocilizumab treatment, to assess the changes induced by the therapy on our selected candidates. Forty-two proteins were differentially expressed between patients' evolution groups at 10% FDR. Twelve proteins showed lower levels in critical patients (fold-changes 1.20-3.58), of which OAS3 and COG5 found their expression increased after COVID-19 specific therapy. Most of the 30 proteins over-expressed in critical patients (fold-changes 1.17-4.43) were linked to inflammation, coagulation, lipids metabolism, complement or immunoglobulins, and a third of them decreased their expression after treatment. We propose a set of candidate proteins for biomarkers of COVID-19 prognosis at the time of hospital admission. The study design employed is distinctive from previous works and aimed to optimize the chances of the candidates to be validated in confirmatory studies and, eventually, to play a useful role in the clinical practice.

The TELE-DD Randomised Controlled Trial on Treatment Adherence in Patients with Type 2 Diabetes and Comorbid Depression: Clinical Outcomes after 18-Month Follow-Up.

Clinical depression is associated with poorer adherence to hypoglycaemic medication in patients with diabetes mellitus, leading to poorer glycaemic control, diabetes management, and increased complications. The main aim of the TELE-DD trial was to demonstrate the efficacy of a proactive and psychoeducational telephonic intervention based on motivational interviewing and collaborative care to reduce nonadherence and improve prognosis in individuals with diabetes mellitus and concurrent depression. DESIGN: The TELE-DD project is a three-phased prospective study including a nested randomised controlled trial. METHODS: The baseline cohort included the entire population of adult patients diagnosed with type 2 diabetes and concurrent depression. A randomised controlled trial was conducted in a selection of patients from the baseline cohort, distributed into a control group (n = 192) and an intervention group (n = 192). Monthly telephonic interventions delivered by specifically trained research nurses were centred on a psychoeducational individualised monitoring protocol including motivational interviewing and collaborative care strategies. Clinical and patient-centred data were systematically collected during an 18-month follow-up including HbA1c, Patient Health Questionnaire, and the Diabetes Distress Scale. RESULTS: During the trial, 18-month follow-up HbA1C levels significantly (p < 0.001) decreased in the intervention group at every follow-up from an average of 8.72 (SD:1.49) to 7.03 (SD:1.09), but slightly increased in the control group from 8.65 (SD:1.40) to 8.84 (SD:1.38). Similar positive results were obtained in depression severity and diabetes distress, LDL-cholesterol, and systolic and diastolic blood pressure, but only at the 18-month follow-up in body mass index reduction. CONCLUSIONS: This is the first trial to concurrently decrease biological and psychological outcomes with a monthly brief telephonic intervention, pointing out that a combined biopsychosocial intervention and collaborative care strategy is essential for current world health challenges. CLINICALTRIALS: gov Identifier: NCT04097483. Patient or Public Contribution: Diabetic patients not belonging to the TELE-DD population or trial sample were consulted during the study design to review and guarantee the clarity and understanding of the trial psychoeducational materials.

Incidence, Risk Factors and Outcomes of Early Acute Kidney Injury After Heart Transplantation: An 18-year Experience.

BACKGROUND: Little is known about the incidence of acute kidney injury (AKI), as defined using the Kidney Disease Improving Global Outcome classification, after heart transplantation (HT). Our objective was to evaluate the impact of AKI in a cohort of HT recipients. (Setting: University Hospital.) METHODS: We studied 310 consecutive HT recipients from 1999 to 2017, with AKI being defined according to the Kidney Disease Improving Global Outcome criteria. Risk factors were analyzed by multivariable analyses, and survival by Kaplan-Meier curves and a risk-adjusted Cox proportional hazards regression model. RESULTS: One hundred twenty-five (40.3%) patients developed AKI, with 73 (23.5%), 18 (5.8%), and 34 (11%) patients having AKI stages 1, 2, and 3, respectively. Cardiac tamponade (odds ratio [OR], 16.82; 95% confidence interval [CI], 1.06-138), acute right ventricular failure (OR, 3.54; 95% CI, 1.82-6.88), and major bleeding (OR, 2.46; 95% CI, 1.18-5.1) were the principal risk factors for AKI. Patients with AKI had a greater hospital mortality (3.8% vs 16%, P < 0.05), especially those requiring renal replacement therapy (46.9% vs 5.4%, P = 0.006). Acute kidney injury requiring renal replacement therapy was independently associated with hospital mortality (OR, 11.03; 95% CI, 4.08-29.8). With a median follow-up after hospital discharge of 6.7 years (interquartile range, 2.4-11.6), overall survival at 1, 5, and 10 years was 95.4%, 85.1%, and 75.4% versus 85.2%, 69.8% and 63.5% among patients without AKI and with AKI stages 2 to 3, respectively (P = 0.08). CONCLUSIONS: The onset of AKI after HT is mainly associated with postoperative complications. Only severe AKI stage predicts worse short-term outcome, with this impact appearing to be lost at long-term follow-up.

Executive summary. Management of influenza infection in solid-organ transplant recipients: consensus statement of the Group for the Study of Infection in Transplant Recipients (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Network for Research in Infectious Diseases (REIPI).

Solid organ transplant (SOT) recipients are at greater risk than the general population for complications and mortality from influenza infection. We have conducted a systematic review to assess the management and prevention of influenza infection in SOT recipients. Recommendations are provided about the procurement of organs from donors with influenza infection. We highlight the importance of the possibility of influenza infection in any SOT recipient presenting upper or lower respiratory symptoms, including pneumonia. The importance of early antiviral treatment of SOT recipients with suspected or confirmed influenza infection and the necessity of annual influenza vaccination are emphasized. The microbiological techniques for diagnosis of influenza infection are reviewed. Guidelines for the use of antiviral prophylaxis are provided. Recommendations for household contacts of SOT recipients with influenza infection and health care workers are also included. Antiviral dose adjustment guidelines are presented for cases of impaired renal function and for pediatric populations.

Management of influenza infection in solid-organ transplant recipients: consensus statement of the Group for the Study of Infection in Transplant Recipients (GESITRA) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) and the Spanish Network for Research in Infectious Diseases (REIPI).

BACKGROUND: Solid organ transplant (SOT) recipients are at greater risk than the general population for complications and mortality from influenza infection. METHODS: Researchers and clinicians with experience in SOT infections have developed this consensus document in collaboration with several Spanish scientific societies and study networks related to transplant management. We conducted a systematic review to assess the management and prevention of influenza infection in SOT recipients. Evidence levels based on the available literature are given for each recommendation. This article was written in accordance with international recommendations on consensus statements and the recommendations of the Appraisal of Guidelines for Research and Evaluation II (AGREE II). RESULTS: Recommendations are provided on the procurement of organs from donors with suspected or confirmed influenza infection. We highlight the importance of the possibility of influenza infection in any SOT recipient presenting upper or lower respiratory symptoms, including pneumonia. The importance of early antiviral treatment of SOT recipients with suspected or confirmed influenza infection and the necessity of annual influenza vaccination are emphasized. The microbiological techniques for diagnosis of influenza infection are reviewed. Guidelines for the use of antiviral prophylaxis in inpatients and outpatients are provided. Recommendations for household contacts of SOT recipients with influenza infection and health care workers in close contact with transplant patients are also included. Finally antiviral dose adjustment guidelines are presented for cases of impaired renal function and for pediatric populations. CONCLUSIONS: The latest scientific information available regarding influenza infection in the context of SOT is incorporated into this document.

Withdrawal of proliferation signal inhibitors due to adverse events in the maintenance phase of heart transplantation.

BACKGROUND: The increasing use of proliferation signal inhibitors (PSIs) has raised the issue of their risk profile. We sought to determine the causes, incidence, risk factors, and consequences of withdrawal due to adverse events of PSIs in maintenance heart transplantation. METHODS: This was a retrospective study from 9 centers of the Spanish Registry for Heart Transplantation. Demographic, clinical, analytic, and evolution data were obtained for patients in whom a PSI (sirolimus or everolimus) was used between October 2001 and March 2009. RESULTS: In the first year, 16% of 548 patients could not tolerate PSIs. This incidence rate stabilized to 3% to 4% per year thereafter. The most frequent causes for discontinuation were edema (4.7%), gastrointestinal toxicity (3.8%), pneumonitis (3.3%), and hematologic toxicity (2.0%). In multivariate analysis, withdrawal of PSI was related to the absence of statin therapy (p = 0.006), concomitant treatment with anti-metabolites (p = 0.006), a poor baseline renal function (p = 0.026), and multiple indications for PSI use (p = 0.04). Drug discontinuation was associated with a decline in renal function (p = 0.045) but not with an excess in mortality (p = 0.42). CONCLUSIONS: In this large cohort of maintenance heart transplant recipients taking a PSI, 16% withdrew treatment in the first year, and 25% had stopped PSI due to severe adverse events by the fourth year. This high rate of toxicity-related PSI withdrawal could limit the clinical utility of this otherwise novel class of immunosuppressive agents.

Anti-cyclic citrullinated peptide and anti-keratin antibodies in patients with idiopathic inflammatory myopathy.

OBJECTIVE: To investigate the prevalence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin antibodies (AKAs) in a cohort of patients with idiopathic inflammatory myopathy. METHODS: In a cross-sectional study, we determined the presence of anti-CCP and AKAs by ELISA and IIF, respectively, in a cohort of 90 consecutive patients with idiopathic inflammatory myopathy. Associations between anti-CCP and clinical manifestations or other autoantibodies were determined with the chi-square and Mann-Whitney U-tests. Radiographs of hands were retrospectively evaluated. Serum autoantibody profile was determined in all patients. RESULTS: Twelve patients were positive to anti-CCP (13.3%); in eight cases values were moderate-high. AKAs were not detected in any patient. Comparison between patients positive and negative to anti-CCP did not show clinical or biological differences. Arthritis joint erosions or positive status to anti-synthetase antibodies were not more frequent in patients with anti-CCP antibodies. Prevalence of RF was the only variable significantly associated with the presence of these antibodies (P = 0.043). CONCLUSIONS: High titres of anti-CCP can occasionally be found in patients with inflammatory myopathy. Therefore, a possible diagnosis of RA should be considered with caution in these patients.

An unusual indication for cardiac transplantation: isolated myocardial tuberculosis.

We report a case of myocardial tuberculosis in an 18-year-old male. He had been diagnosed with isolated asymmetrical septal hypertrophy cardiomyopathy and presented severe congestive heart failure for 4 months. Echocardiography and magnetic resonance studies showed localized echodense shadows and cavities in the thickness of the left ventricle myocardium with severe myocardial dysfunction. No contraindications for cardiac transplantation were found and this was planned and performed. Histology of the myocardium was consistent with the diagnosis of myocardial tuberculosis. The patient's post-operative course was uneventful, and he was discharged with anti-tuberculosis medication.

Biological and theoretical relevance of some connectionist assumptions. The development of conceptual networks

For the study of psychological processes in cognitive science modelling two general approaches rule nowadays research: Artificial Intelligence (top-down) functional symbolic models, and Connectionist (bottom-up) neural networks modelling. Our goal in this paper is to show that analyzing the theoretical level of description and explanation of this models an important theoretical gap between both is found. Connectionist modelling through neural networks face at present several theoretical problems that have to be accounted in order to build realistic and feasible models of the brain. The lack of biological constraints, network stability or serial behaviour, for example, are relevant issues to bear in mind. Our proposed model, conceptual networks, can be located halfway between the traditional semantic networks and artificial neural networks modelling, and is presented as an attempt of building a necessary bridge between this levels of description, focussing on the correspondence between the functional level and the level that can be modelled by artificial neural networks. The elements and functioning of conceptual networks are based in biological and psychological constraints necessary to build realistic models of actual cognitive processes in brain functioning (AU)

Relevancia teórica y biológica de algunos postulados conexionistas. El desarrollo de redes conceptuales. En el estudio de los procesos psicológicos a través de modelamiento en ciencia cognitiva, dos aproximaciones generales se imponen actualmente en investigación: los modelos funcionales o simbólicos (descendientes), provenientes de la Inteligencia Artificial, y los modelos conexionistas (ascendentes) a través del modelamiento de redes neuronales artificiales. Nuestro objetivo en este trabajo es mostrar que a través del análisis del nivel teórico de descripción y explicación de estos modelos, encontramos una distancia importante de separación. El modelamiento conexionista a través de redes neuronales se enfrenta en la actualidad a numerosos problemas teóricos que deben ser superados con el fin de construir modelos admisibles y realistas de la estructura del cerebro. La carencia de restricciones biológicas, la estabilidad de la red o la conducta serial, por ejemplo, son aspectos importantes que deben ser tenidos en cuenta. Nuestro modelo propuesto, las redes conceptuales, puede ser enclavado entre las redes semánticas tradicionales y el modelamiento a través de redes neuronales artificiales, y es presentado como un intento de construir un puente entre los niveles de descripción del cerebro citados anteriormente, deteniéndonos en la correspondencia entre el nivel funcional y el nivel que puede ser modelado por las redes neuronales artificiales. Los elementos y el funcionamiento de las redes conceptuales están basados en restricciones biológicas y psicológicas necesarias para construir modelos realísticos de los procesos cognitivos auténticos del funcionamiento del cerebro (AU)