Artificial neural networks as alternative tool for minimizing error predictions in manufacturing ultradeformable nanoliposome formulations.

This work was aimed at determining the feasibility of artificial neural networks (ANN) by implementing backpropagation algorithms with default settings to generate better predictive models than multiple linear regression (MLR) analysis. The study was hypothesized on timolol-loaded liposomes. As tutorial data for ANN, causal factors were used, which were fed into the computer program. The number of training cycles has been identified in order to optimize the performance of the ANN. The optimization was performed by minimizing the error between the predicted and real response values in the training step. The results showed that training was stopped at 10 000 training cycles with 80% of the pattern values, because at this point the ANN generalizes better. Minimum validation error was achieved at 12 hidden neurons in a single layer. MLR has great prediction ability, with errors between predicted and real values lower than 1% in some of the parameters evaluated. Thus, the performance of this model was compared to that of the MLR using a factorial design. Optimal formulations were identified by minimizing the distance among measured and theoretical parameters, by estimating the prediction errors. Results indicate that the ANN shows much better predictive ability than the MLR model. These findings demonstrate the increased efficiency of the combination of ANN and design of experiments, compared to the conventional MLR modeling techniques.

The Compositional HJ-Biplot-A New Approach to Identifying the Links among Bioactive Compounds of Tomatoes.

Tomatoes have been described as a functional food because of their particular composition of different bioactive compounds. In this study, the proximate composition, minerals and trace elements, and antioxidant compounds were determined in two tomato cultivars (Mariana and Dunkan) that were grown in Gran Canaria (Spain) either conventionally or hydroponically. Although compositional data of this type require being subjected to the specific statistical techniques of compositional analysis, this approach has not usually been considered in this context. In the present case, a compositional Mann-Whitney U test of the data showed significant differences for each factor (cultivar and cultivation system) in several of the compositional variables studied. For the differences between cultivars, these parameters were the protein, Mg, lycopene, ascorbic acid, citric acid, and fumaric acid contents. For the differences between cultivation systems, they were mainly those of the mineral and trace elements group. Although one-year data are insufficient to make clear relationship among compounds because more repetitions in several localities and years are necessary, the compositional HJ-biplot (in which the links provide estimates of the linear relationship among variables) results agreed with other scientific results about linear relationship among some compounds analyzed.

[Faciobrachial dystonic seizures. Semiologic diagnosis in limbic encephalitis]. / Crisis distónicas faciobraquiales. Diagnóstico semiológico en la encefalitis límbica.

Limbic encephalitis (LE) associated with positive potassium channel complex antibodies often manifests with faciobrachial dystonic seizures (FBDS). We retrospectively analyze two cases, admitted to our video-EEG unit between 2006 and 2014. Both patients were males, aged 66 and 76 years respectively, presenting with brief, but very frequent uni/bilateral dystonic brachial movements, hand posturing and ipsilateral facial grimacing. Severe hyponatremia was found in both patients who went on to develop cognitive impairment. Immunosuppressive therapy improved both seizures and cognitive dysfunction. Serology testing confirmed anti VGKC antibody presence. FBDS are often the first manifestation of LE associated to positive anti VGKC antibodies, and are refractory to treatment with antiepileptic drugs. Early diagnosis and treatment of FBDS with immunosuppressive therapy is important, not only because of seizure suppression, but also because it may help limit the extent of the cognitive damage.

Serological survey suggests circulation of coronavirus on wild Suina from Argentina, 2014-2017.

Swine coronaviruses affecting pigs have been studied sporadically in wildlife. In Argentina, epidemiological surveillance of TGEV/PRCV is conducted only in domestic pigs. The aim was to assess the prevalence of TGEV/PRCV in wild Suina. Antibodies against these diseases in wild boar and captive collared peccary were surveyed by ELISA. Antibodies against TGEV were found in three collared peccaries (n = 87). No TGEV/PRCV antibodies were detected in wild boar (n = 160). Preventive measures should be conducted in contact nodes where the transmission of agents may increase. Epidemiological surveillance in wildlife populations and in captive animals before their reintroduction should be attempted.

Transient global amnesia: clinical features and prognostic factors suggesting recurrence.

OBJECTIVE: The risk of recurrence of new amnesia events in patients having previously experienced transient global amnesia (TGA) ranges between 2.9-23.8%. Our objective was to search for recurrence predictors in TGA patients. METHODS: Retrospective analysis to identify recurrence predictors in a cohort of 203 TGA patients from a single center in Buenos Aires, Argentina, diagnosed between January 2011 and March 2017 Clinical features and complementary studies (laboratory results, jugular vein Doppler ultrasound and brain MRI) were analyzed. Comparison between patients with recurrent versus single episode TGA was performed, applying a multivariate logistic regression model. RESULTS: Mean age at presentation was 65 years (20-84); 52% were female. Median time elapsed between symptom onset and ER visit was two hours, with the average episode duration lasting four hours. Mean follow-up was 22 months. Sixty-six percent of patients referred to an identifiable trigger. Jugular reflux was present in 66% of patients; and 22% showed images with hippocampus restriction on diffusion-weighted MRI. Eight percent of patients had TGA recurrence. Patients with recurrent TGA had a more frequent history of migraine than patients without recurrence (37.5% vs. 14%; p = 0.03). None of the other clinical characteristics and complementary studies were predictors of increased risk of recurrence. CONCLUSIONS: Patients with migraine may have a higher risk of recurrent TGA. None of the other clinical characteristics evaluated allowed us to predict an increased risk of recurrence. Although the complementary studies allowed us to guide the diagnosis, they did not appear to have a significant impact on the prediction of recurrence risk.

Identification of Relevant Phytochemical Constituents for Characterization and Authentication of Tomatoes by General Linear Model Linked to Automatic Interaction Detection (GLM-AID) and Artificial Neural Network Models (ANNs).

There are a large number of tomato cultivars with a wide range of morphological, chemical, nutritional and sensorial characteristics. Many factors are known to affect the nutrient content of tomato cultivars. A complete understanding of the effect of these factors would require an exhaustive experimental design, multidisciplinary scientific approach and a suitable statistical method. Some multivariate analytical techniques such as Principal Component Analysis (PCA) or Factor Analysis (FA) have been widely applied in order to search for patterns in the behaviour and reduce the dimensionality of a data set by a new set of uncorrelated latent variables. However, in some cases it is not useful to replace the original variables with these latent variables. In this study, Automatic Interaction Detection (AID) algorithm and Artificial Neural Network (ANN) models were applied as alternative to the PCA, AF and other multivariate analytical techniques in order to identify the relevant phytochemical constituents for characterization and authentication of tomatoes. To prove the feasibility of AID algorithm and ANN models to achieve the purpose of this study, both methods were applied on a data set with twenty five chemical parameters analysed on 167 tomato samples from Tenerife (Spain). Each tomato sample was defined by three factors: cultivar, agricultural practice and harvest date. General Linear Model linked to AID (GLM-AID) tree-structured was organized into 3 levels according to the number of factors. p-Coumaric acid was the compound the allowed to distinguish the tomato samples according to the day of harvest. More than one chemical parameter was necessary to distinguish among different agricultural practices and among the tomato cultivars. Several ANN models, with 25 and 10 input variables, for the prediction of cultivar, agricultural practice and harvest date, were developed. Finally, the models with 10 input variables were chosen with fit's goodness between 44 and 100%. The lowest fits were for the cultivar classification, this low percentage suggests that other kind of chemical parameter should be used to identify tomato cultivars.

Cognitive reserve and Aß1-42 in mild cognitive impairment (Argentina-Alzheimer's Disease Neuroimaging Initiative).

BACKGROUND: The purpose of this study was to investigate the relationship between cognitive reserve and concentration of Aß1-42 in the cerebrospinal fluid (CSF) of patients with mild cognitive impairment, those with Alzheimer's disease, and in control subjects. METHODS: Thirty-three participants from the Argentina-Alzheimer's Disease Neuroimaging Initiative database completed a cognitive battery, the Cognitive Reserve Questionnaire (CRQ), and an Argentinian accentuation reading test (TAP-BA) as a measure of premorbid intelligence, and underwent lumbar puncture for CSF biomarker quantification. RESULTS: The CRQ significantly correlated with TAP-BA, education, and Aß1-42. When considering Aß1-42 levels, significant differences were found in CRQ scores; higher levels of CSF Aß1-42 were associated with higher CRQ scores. CONCLUSION: Reduced Aß1-42 in CSF is considered as evidence of amyloid deposition in the brain. Previous results suggest that individuals with higher education, higher occupational attainment, and participation in leisure activities (cognitive reserve) have a reduced risk of developing Alzheimer's disease. Our results support the notion that enhanced neural activity has a protective role in mild cognitive impairment, as evidenced by higher CSF Aß1-42 levels in individuals with more cognitive reserve.

Sedoanalgesia para procedimientos en Unidad de Cuidados Intensivos Pediátricos (UCIP). Farmacología, efectos secundarios y control de calidad / Sedoanalgesia for procedures in Pediatric Intensive Care Unit (PICU). Pharmacology, side effects and quality control

OBJETIVOS: Analizar los fármacos más utilizados para sedoanalgesia en procedimientos realizados en una Unidad de Cuidados Intensivos Pediátricos (UCIP), medir su efectividad (nivel de sedación), efectos secundarios y control de calidad. MATERIAL Y MÉTODOS: Estudio prospectivo, observacional y descriptivo. Se recogieron datos epidemiológicos y clínicos, fármaco/s utilizado/s, nivel de sedación alcanzado, incidencias o efectos adversos y escalas de satisfacción, de pacientes de 0 a 18 años sometidos a procedimientos que precisaron sedoanalgesia. RESULTADOS: Se incluyeron 112 pacientes con una edad media de 8,3 años. El fármaco más utilizado fue el propofol (64,3%), seguido de la asociación de ketamina con midazolam (16,1%) y del sevofluorano (12,5%). En el 70,5% de los pacientes se alcanzó un nivel de sedación profunda, sin diferencias estadísticamente significativas entre los distintos fármacos. Se registraron efectos adversos en un 51,8% de pacientes, principalmente desaturación, con una frecuencia mayor al emplear propofol (p< 0,05). La puntuación en la satisfacción alcanzó el valor máximo en todos los padres encuestados, sin hallarse diferencias significativas en función del procedimiento, fármaco, nivel de sedación o efectos adversos. En el 80% de los profesionales la puntuación alcanzó ese mismo valor. CONCLUSIONES: El fármaco más utilizado y con mayor eficacia es el propofol, aunque se asocia más frecuentemente con efectos adversos. El nivel de sedoanalgesia fue adecuado en el momento de iniciar los procedimientos. El grado de satisfacción es óptimo en la mayor parte de los encuestados, aunque fue registrado en menos de la mitad de los procedimientos

OBJECTIVES: To analyze the drugs most used for sedoanalgesia in procedures performed in a Pediatric Intensive Care Unit (PICU), to measure their effectiveness (level of sedation achieved), the main side effects and to carry out a quality control. MATERIAL AND METHODS: Prospective, observational and descriptive study. Epidemiological and clinical data, drug (s) used, level of sedation achieved, incidences or adverse effects, and satisfaction scales were collected from patients from 0 to 18 years of age who underwent procedures that required sedation and analgesia. RESULTS: 112 patients with an average age of 8.3 years were included. The most widely used drug was propofol (64.3%), followed by the association of ketamine with midazolam (16.1%) and sevofluorane (12.5%). In 70.5% of the patients, a level of deep sedation was reached, with no statistically significant differences between the different drugs used. Adverse effects were recorded in 51.8% of patients, mainly desaturation, with a higher frequency when using propofol (p <0.05). Satisfaction score was maximal in all the parents surveyed, without finding significant differences based on the procedure, drug, level of sedation or adverse effects. In 80% of the professionals the score was also maximal. CONCLUSION: The most used and with the highest efficacy in absolute values drug was propofol, although it was more frequently associated with adverse effects. The level of sedoanalgesia was adequate at the time of initiating the procedures. The degree of satisfaction was optimal in most of the respondents, although it was registered in less than half of the procedures

Transient global amnesia: clinical features and prognostic factors suggesting recurrence / Amnesia global transitoria: características clínicas y factores pronósticos sugestivos de recurrencia

ABSTRACT The risk of recurrence of new amnesia events in patients having previously experienced transient global amnesia (TGA) ranges between 2.9-23.8%. Objective: Our objective was to search for recurrence predictors in TGA patients. Methods: Retrospective analysis to identify recurrence predictors in a cohort of 203 TGA patients from a single center in Buenos Aires, Argentina, diagnosed between January 2011 and March 2017 Clinical features and complementary studies (laboratory results, jugular vein Doppler ultrasound and brain MRI) were analyzed. Comparison between patients with recurrent versus single episode TGA was performed, applying a multivariate logistic regression model. Results: Mean age at presentation was 65 years (20-84); 52% were female. Median time elapsed between symptom onset and ER visit was two hours, with the average episode duration lasting four hours. Mean follow-up was 22 months. Sixty-six percent of patients referred to an identifiable trigger. Jugular reflux was present in 66% of patients; and 22% showed images with hippocampus restriction on diffusion-weighted MRI. Eight percent of patients had TGA recurrence. Patients with recurrent TGA had a more frequent history of migraine than patients without recurrence (37.5% vs. 14%; p = 0.03). None of the other clinical characteristics and complementary studies were predictors of increased risk of recurrence. Conclusions: Patients with migraine may have a higher risk of recurrent TGA. None of the other clinical characteristics evaluated allowed us to predict an increased risk of recurrence. Although the complementary studies allowed us to guide the diagnosis, they did not appear to have a significant impact on the prediction of recurrence risk.

RESUMEN El riesgo de recurrencia de nuevos eventos de amnesia en pacientes que han experimentado previamente Amnesia Global Transitoria (AGT) oscila entre el 2.9-23.8%. Objetivo: Nuestro objetivo fue buscar predictores de recurrencia en pacientes con AGT. Métodos: Análisis retrospectivo de una cohorte de 203 pacientes con AGT de un único centro en Buenos Aires, Argentina, diagnosticados entre enero-2011 y marzo-2017 Se analizaron las características clínicas y los estudios complementarios (laboratorio, Doppler de vena yugular y RM encéfalo). Se comparó el grupo de AGT recurrente versus episodio único, aplicando un modelo de regresión logística multivariada. Resultados: la edad promedio de presentación fue de 65 años (20-84); 52% mujeres. La mediana del tiempo transcurrido entre el inicio de los síntomas y la visita a la sala de emergencia fue de 2 horas, con una duración promedio del episodio de 4 horas. El seguimiento medio fue de 22 meses. 66% de los pacientes tuvieron un desencadenante identificable. El reflujo yugular estuvo presente en el 66% de los pacientes y el 22% mostró imágenes restrictivas en DWI a nivel hipocampal. 8% de los pacientes presentaron recurrencia. Los pacientes con AGT recurrente tuvieron un historial de migraña más frecuente (37.5% vs. 14%; p=0.03). Ninguna de las otras características clínicas y estudios complementarios fueron predictores de mayor riesgo de recurrencia. Conclusiones: los pacientes con migraña pueden tener un mayor riesgo de recurrencia de AGT. Ninguna de las otras características clínicas evaluadas nos permitió predecir un mayor riesgo de recurrencia. Aunque los estudios complementarios nos permitieron orientar el diagnóstico, no pareció tener un impacto significativo en la predicción del riesgo de recurrencia.

Utility of the Spanish version of the FTLD-modified CDR in the diagnosis and staging in frontotemporal lobar degeneration.

INTRODUCTION: The Clinical Dementia Rating Scale (CDR) is a tool designed to quantify the severity of dementia symptoms and is also useful to assess disease progression, in Alzheimer's disease (AD). A new version of the scale was developed by adding two extra domains that focused on the core aspects of frontotemporal dementia symptomatology, Language and Behavior/Comportment/Personality. OBJECTIVES: In this study, we adapted and validated the modified CDR scale in our setting and language (Rioplatense-Spanish). MATERIALS AND METHODS: 46 patients with probable AD, 27 behavioral variant of Frontotemporal Dementia (bvFTD), 18 Primary Progressive Aphasia (PPA) and 40 healthy participants were included. The adapted version of the scale was administered by a blind rater who interviewed patients together with patient's caregiver. RESULTS: Using ROC curves, the domain language and behavior were superior to the memory domain in accuracy for detecting PPA and bvFTD, respectively, but both of them had equivalent diagnostic accuracies for probable AD. Logistic regression analyses showed that either the LANG or BEHAV domains significantly improved the discrimination between probable AD, bvFTD and PPA. CONCLUSIONS: The Spanish version of the modified CDR adds value for the characterization of the non-amnestic symptoms in patients with neurodegenerative dementias.

Single-dose oral lacosamide in refractory simple partial status epilepticus: case report and review.

OBJECTIVES: This study aimed to present 2 patients with simple partial refractory status epilepticus (RSE) treated with a single oral lacosamide (LCM) dose and to review the literature on this topic. METHOD: A retrospective description of 2 patients with simple partial RSE treated with 300 mg of LCM per os (p.o.) and a literature review were done. RESULTS: Both patients responded to single-dose oral LCM treatment with seizure cessation after 30 minutes. CONCLUSIONS: This is the first report on successful treatment of simple partial RSE with a single-dose of LCM p.o.. Oral LCM might represent an option for treatment of patients presenting with simple partial RSE.

Análisis bibliométrico de la producción científica sobre cuidados paliativos en Scopus / Bibliometric analysis of the scientific production on palliative care in Scopus

Introducción y objetivo: Los cuidados paliativos son un enfoque que mejora la calidad de vida de los pacientes terminales. En los siguientes años habrá una gran necesidad de este servicio debido al aumento de la población de edad avanzada y de las enfermedades que afectan a este grupo. No todos los países de Latinoamérica y el Caribe tienen políticas nacionales de cuidados paliativos. El objetivo de este estudio es describir la producción científica sobre cuidados paliativos en Latinoamérica y el Caribe. Métodos: Se realizó un estudio bibliométrico sobre cuidados paliativos en la base de datos Scopus entre 1990 y 2019 cuyos autores tengan al menos una filiación de Latinoamérica y el Caribe. Resultados: Se obtuvo un total de 2030 documentos, observándose un crecimiento sostenido desde el año 2000. Los países con la mayor cantidad de artículos publicados fueron Brasil con 948 (45,65 %), México con 373 (18,36 %) y Argentina con 274 (13,48 %). El conglomerado por palabras clave nos mostró la formación de 3 grupos: terapia paliativa, terapia paliativa en cáncer y grupo etario. Discusión: Si bien en los últimos años ha habido un aumento en el número de artículos publicados, el aporte de cada país es desigual; los 3 primeros países aportan más del 75 % del total de las publicaciones. Se debe promover las políticas nacionales y la investigación en cuidados paliativos con el objetivo de encontrar otros enfoques y terapias para pacientes que requieran cuidados paliativos. (AU)

Introduction and objective: Palliative care is an approach that improves the quality of life in terminally ill patients. In the coming years, there will be a great need for this service due to an increase in the elderly population and in the diseases that affect this age group. Not all Latin American and Caribbean countries have national palliative care policies. The aim of this study was to describe the scientific production on palliative care in Latin America and the Caribbean. Methods: A bibliometric study on palliative care was conducted in the Scopus database between 1990 and 2019, focusing on papers whose authors had at least one affiliation from Latin America and the Caribbean. Results: A total of 2030 documents were obtained, showing a sustained growth since 2000. The countries with the highest number of published articles were Brazil with 948 (45.65 %), Mexico with 373 (18.36 %), and Argentina with 274 (13.48 %). Clustering by keywords showed the formation of 3 groups: palliative therapy, palliative therapy in cancer, and age group. Discussion: Although there has been an increase in the number of articles published in recent years, the contribution of each country is unequal, with the first 3 countries accounting for more than 75 % of the total number of publications. National policies and research in palliative care should be promoted with the aim of finding other approaches and therapies for patients requiring palliative care. (AU)

Evaluación de tres métodos para recolección de pupas de Aedes aegypti (Diptera: Culicidae) en criaderos artificiales / Evaluation of three methods for collecting pupae of Aedes aegypti (Diptera: Culicidae) in drums

La evaluación de la abundancia de pupas es una herramienta de gran importancia que nos da información en relación al criadero-riesgo, aportando estimaciones de poblaciones adultas de Ae.aegypti. Con miras a determinar la productividad de criaderos del vector, se evaluaron tres métodos de muestreo para la recolección de pupas en recipientes que almacenan agua (pipotes de 200 litros) para consumo humano. Los métodos: trampa embudo (TE), balón de vidrio (BV) y aro colador (AC), fueron replicados entre 10 y 5 pipotes por día, para un total de 6 días. La TE tuvo un período de observación de 24 horas/ pipote, mientras que un promedio de tres colectas/día/pipote fueron realizadas para el BV y AC. Fueron sembradas 100, 50 y 10 pupas en los pipotes y se evaluó su recuperación a través de los métodos descritos, los valores medios de recuperación y el porcentaje de efectividad fue medido. En la siembra de 100 pupas, los valores medios de recuperación fueron: TE= 17.5, BV= 86.6 y AC= 93.7. Para 50 y 10 pupas sembradas se obtuvieron valores de TE= 7.9 y 1.8, BV= 46.2 y 8.8, AC= 45.6 y 9.1, respectivamente. Diferencias significativas entre los métodos (p<0.0001) fueron observadas para cada una de las siembras evaluadas. El porcentaje de efectividad relacionado con el numero de pupas recuperadas fue: TE=17.5 por ciento, 15.9 por ciento y 18 por ciento, BV= 86.6 por ciento, 92.4 por ciento y 88.3 por ciento y AC=93.7 por ciento, 91.3 por ciento y 90.6 por ciento, para 100, 50 y 10 pupas sembradas, respectivamente. Se observó consistencia para cada método en los porcentajes de recuperación. El AC fue más efectivo en la recuperación con 100 pupas (93.7 por ciento) y 10 pupas (90.6 por ciento) al compararlo con el BV (86.6 por ciento y 88.3 por ciento), observándose consistencia en los valores para 50 pupas. A la luz de los resultados obtenidos, el método de AC se podría considerar como una herramienta útil para el muestreo de pupas a ser incorporada en la vigilancia entomológica de campo, facilitando la evaluación de los criaderos para optimizar las operaciones de control vectorial