Tucker3-PCovR: The Tucker3 principal covariates regression model.

In behavioral research, it is very common to have manage multiple datasets containing information about the same set of individuals, in such a way that one dataset attempts to explain the others. To address this need, in this paper the Tucker3-PCovR model is proposed. This model is a particular case of PCovR models which focuses on the analysis of a three-way data array and a two-way data matrix where the latter plays the explanatory role. The Tucker3-PCovR model reduces the predictors to a few components and predicts the criterion by using these components and, at the same time, the three-way data is fitted by the Tucker3 model. Both the reduction of the predictors and the prediction of the criterion are done simultaneously. An alternating least squares algorithm is proposed to estimate the Tucker3-PCovR model. A biplot representation is presented to facilitate the interpretation of the results. Some applications are made to empirical datasets from the field of psychology.

Neuroendocrine Tumors: An Analysis of Prevalence, Incidence, and Survival in a Hospital-Based Study in Ecuador.

Neuroendocrine tumors (NETs) represent a heterogeneous malignancy group of neoplasms, with a limited amount of data from Latin America. Thus, this observational study aimed to provide data about the prevalence, incidence, and survival rates for NET in Ecuadorian hospitals. The study was conducted using data from the Society for the Fight Against Cancer (SOLCA). We evaluated patients with NETs (2000−2020) using the HJ-Biplot method and Cox proportional hazards. Annual age-adjusted incidence and limited-duration prevalence in multivariable analyses as well as hazard ratios (HRs) for mortality and survival were obtained. In the years 2000−2020, the age-adjusted incidence rate increased by 9-fold in the stomach and by 7-fold in the breast. The incidence rates were 1.38 per 100,000 persons in the lung and at 1.79 per 100,000 persons in gastroenteropancreatic sites (rectum, stomach, and pancreas). The prevalence increased from 0.0027% in 2000 to 0.0736% in 2019 and 0.0245% in 2020. Overall survival was worse for metastatic NETs (HR, 4.061; 95% CI, 1.932−8.540; p < 0.001) and advanced local NETs (HR, 2.348; 95% CI, 1.007−5.475 p < 0.048) than for localized NETs. In conclusion, the NET incidence increased in the last 20 years and survival decreased over time, especially for metastatic tumors in the pancreas and the nostril.

Clinical related factors to neuroendocrine tumors in Ecuadorian patients: a logistic biplot approach / Factores clínicos asociados a tumores neuroendocrinos en pacientes ecuatorianos: un análisis biplot logístico

Abstract Neuroendocrine tumors (NETs) are relative rare, affecting neuroendocrine cells throughout the body. Most tumors are diagnosed at advanced stages. NETs prevalence has increased in the last years but there is little data available in developing countries. The aim of this study was to describe symptoms associated with NETs in patients of the Society for the Fight Against Cancer (SOLCA) in Ecuador from 2005 to 2020; using logistic biplots, in a hospital database, generating binary responses (presence/absence) relevant to this study. The results showed that the mean age was 59 and the study showed no difference in prevalence between genders. NETs were mainly found in lungs (19%), followed by stomach (18%) and skin (9%). Most patients had pathological diagnosis G2 and G3 (30% and 70%, respectively). Symptoms as cough, dyspnea, weight loss, diarrhea, constipation, abdominal pain, dyspepsia, hypertensive crisis, distended abdomen and intestinal obstruction had p values <0.05. Additionally, the statistical analysis showed that cough and intestinal obstruction were also common, bearing in mind that patients had most frequent NETs in the lungs and skin. In summary, our results indicate that symptoms of NETs patients were positively associated with lung and skin. Further investigation is needed focusing on the type of NETs and their symptoms in order to establish an early marker for diagnosis.

Resumen Los tumores neuroendocrinos (TNE) son relativamente raros y afectan a las células neuroendocrinas de todo el cuerpo. La mayoría de los tumores se diagnostican en etapas avanzadas. La prevalencia de los TNE ha aumentado en los últimos años, pero hay pocos datos en los países en desarrollo. El objetivo de este estudio fue determinar los síntomas asociados a los TNE en pacientes de la Sociedad de Lucha contra el Cáncer (SOLCA) en Ecuador entre 2005 y 2020, utilizando biplots logísticos en una base de datos hospitalaria, generando respuestas binarias (presencia / ausencia) relevantes para este estudio. Los resultados mostraron que la edad promedio era de 59 años y el estudio no encontró diferencias en la prevalencia entre géneros. Los TNE se encontraron con mayor frecuencia en los pulmones (19%), seguidos del estómago (18%) y piel (9%). La mayoría de los pacientes tenían diagnóstico patológico G2 y G3 (30% y 70% respectivamente). Los síntomas como tos, disnea, pérdida de peso, diarrea, estreñimiento, dolor abdominal, dispepsia, crisis hipertensiva, abdomen distendido y obstrucción intestinal tuvieron valores de p <0,05. Además, el análisis estadístico mostró que la tos y la obstrucción intestinal también eran comunes, teniendo en cuenta que los pacientes tenían TNE más frecuentes en los pulmones y la piel. En resumen, nuestros resultados indican que los síntomas de los pacientes con TNE se asociaron positivamente con los pulmones y la piel. Se necesitan más investigaciones que se centren en el tipo de TNE y sus síntomas a fin de establecer un marcador más temprano para el diagnóstico.

Seroprevalence of SARS-CoV-2 Antibodies and Factors Associated with Seropositivity at the University of Salamanca: The DIANCUSAL Study.

BACKGROUND: Systematic screening for antibodies against SARS-CoV-2 is a crucial tool for surveillance of the COVID-19 pandemic. The University of Salamanca (USAL) in Spain designed a project called "DIANCUSAL" (Diagnosis of New Coronavirus, COVID-19, in University of Salamanca) to measure antibodies against SARS-CoV-2 among its ~34,000 students and academic staff, as the influence of the university community in the spread of the SARS-CoV-2 pandemic in the city of Salamanca and neighboring towns hosting USAL campuses could be substantial. OBJECTIVE: The aim of this study was to estimate the prevalence of SARS-CoV-2 antibodies among USAL students, professors and staff and to evaluate the demographic, academic, clinical and lifestyle and behavioral factors related to seropositivity. METHODOLOGY: The DIANCUSAL study is an ongoing university population-based cross-sectional study, with the work described herein conducted from July-October 2020. All USAL students, professors and staff were invited to complete an anonymized questionnaire. Seroprevalence of anti-SARS-CoV-2 antibodies was detected and quantified by using chemiluminescent assays for IgG and IgM. PRINCIPAL FINDINGS: A total of 8197 (24.71%) participants were included. The mean age was 31.4 (14.5 SD) years, and 66.0% of the participants were female. The seroprevalence was 8.25% overall and was highest for students from the education campus (12.5%) and professors from the biomedical campus (12.6%), with significant differences among faculties (p = 0.006). Based on the questionnaire, loss of smell and fever were the symptoms most strongly associated with seropositivity, and 22.6% of seropositive participants were asymptomatic. Social distancing was the most effective hygiene measure (p = 0.0007). There were significant differences in seroprevalence between participants with and without household exposure to SARS-CoV-2 (p = 0.0000), but not between students who lived in private homes and those who lived in dormitories. IgG antibodies decreased over time in the participants with confirmed self-reported COVID-19 diagnoses. CONCLUSIONS: The analysis revealed an overall 8.25% seroprevalence at the end of October 2020, with a higher seroprevalence in students than in staff. Thus, there is no need for tailored measures for the USAL community as the official average seroprevalence in the area was similar (7.8% at 22 June and 12.4 at 15 November of 2020). Instead, USAL members should comply with public health measures.

Análisis multivariado HJ-Biplot de la ocurrencia de Helicobacter pylori como riesgo para cáncer gástrico, en la ciudadela el Cristo de Consuelo, Milagro Ecuador / HJ-Biplot multivariate analysis of the occurrence of Helicobacter pylori as a risk for gastric cancer, in the citadel of El Cristo de Consuelo, Milagro Ecuador

El Helicobacter pylori, es el causante del mayor número de úlceras y cáncer gástrico a nivel mundial. Población de 15 a 20 años, de escasos recursos y con mayor precariedad en el funcionamiento de los servicios públicos como es el agua potable son altamente vulnerables. Por lo que se planteó como objetivo, realizar un análisis multivariado HJ-Biplot de la ocurrencia de H. pylori como riesgo para cáncer gástrico, en la ciudadela el Cristo de Consuelo, Milagro Ecuador. Estudio epidemiológico transversal, descriptiva y de tipo observacional, contó con una población finita de 230 personas. Técnicas de recolección de datos: la encuesta, la observación directa y la detección de H. pylori en las muestras de heces. El análisis de las muestras biológicas se realizó mediante el método de Elisa en muestras de suero y heces. A los datos obtenidos se les aplicó el método de análisis multivariado bidireccional llamado HJ-Biplot, reflejándose en las variables las relaciones de las composiciones químicas, físicas y biológicas. Los resultados conforman dos grupos de puntos de muestra que coinciden satisfactoriamente con las estaciones de la región. Con este estudio se demuestra que los métodos estadísticos multivariantes son valiosos para interpretar conjuntos de datos complejos, concretamente, para la red de prevalencia de cáncer gástrico causado por el bacilo H. pylori, ha ido en aumento en los últimos años tanto en el Ecuador como en el resto del mundo. Es necesario que se establezcan los mecanismos de control de los agentes causantes de la propagación de este bacilo lo que incidirá en la disminución en la tasa de crecimiento del cáncer gástrico(AU)

Helicobacter pylori is the cause of the highest number of ulcers and gastric cancer worldwide. Population aged 15 to 20 years, with limited resources and with greater precariousness in the operation of public services such as drinking water, are highly vulnerable. Therefore, the objective was to carry out a multivariate HJ-Biplot analysis of the occurrence of H. pylori as a risk for gastric cancer, in the citadel of Cristo de Consuelo, Milagro Ecuador. Cross-sectional, descriptive and observational epidemiological study, had a finite population of 230 people. Data collection techniques: survey, direct observation and detection of H. pylori in stool samples. Analysis of biological samples was performed using the Elisa method in samples of serum and feces. The obtained data were applied the method of bi-directional multivariate analysis called HJ-Biplot, reflecting in the variables the relationships of the chemical, physical and biological compositions. The results form two groups of sample points that successfully coincide with the stations in the region. This study shows that multivariate statistical methods are valuable for interpreting complex data sets, specifically for the prevalence network of gastric cancer caused by the H. pylori bacillus, which has been increasing in recent years both in Ecuador and in the rest of the world. it is necessary to establish the control mechanisms of the agents that cause the spread of this bacillus, which will affect the decrease in the growth rate of gastric cáncer(AU)

Early detection of black Sigatoka in banana leaves using hyperspectral images.

PREMISE: Black Sigatoka is one of the most severe banana (Musa spp.) diseases worldwide, but no methods for the rapid early detection of this disease have been reported. This paper assesses the use of hyperspectral images for the development of a partial-least-squares penalized-logistic-regression (PLS-PLR) model and a hyperspectral biplot (HS biplot) as a visual tool for detecting the early stages of black Sigatoka disease. METHODS: Young (three-month-old) banana plants were inoculated with a conidia suspension of the black Sigatoka fungus (Pseudocercospora fijiensis). Selected infected and control plants were evaluated using a hyperspectral imaging system at wavelengths in the range of 386-1019 nm. PLS-PLR models were run on the hyperspectral data set. The prediction power was assessed using leave-one-out cross-validation as well as external validation. RESULTS: The PLS-PLR model was able to predict the presence of the disease with a 98% accuracy. The wavelengths with the highest contribution to the classification ranged from 577 to 651 nm and from 700 to 1019 nm. DISCUSSION: PLS-PLR and HS biplot effectively estimated the presence of black Sigatoka disease at the early stages and can be used to graphically represent the relationship between groups of leaves and both visible and near-infrared wavelengths.

Memory and Executive Dysfunction Predict Complex Activities of Daily Living Impairment in Amnestic Multi-Domain Mild Cognitive Impairment.

BACKGROUND: Specific cognitive alterations could be one of the predictors that lead to the complex activities of daily living (CADL) impairment in mild cognitive impairment (MCI) and, hence, help to explain the continuum between MCI and dementia. OBJECTIVE: We aimed to reevaluate the existing uncertainty regarding the impact of memory and executive functions on CADL in patients with MCI. METHODS: Caregivers of 161 patients with amnestic multi-domain MCI and of 150 patients with incipient Alzheimer's disease as well as 100 age-, sex-, and education-matched controls, completed the Interview for Deterioration in Daily Living Activities in Dementia, a suitable instrument for the description and discrimination of CADL. In addition, all patients and controls were assessed with a neuropsychological battery to measure explicit memory and executive functions performance. RESULTS: Multiple regression analyses showed that in the group of patients with amnestic multi-domain MCI, 67.4% of the variability of the CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 41.8% by different explicit memory components impairment (p < 0.0001). Further, in patients with incipient AD, 44.0% of the variability of CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 39.9% by different explicit memory components worsening (p < 0.0001). CONCLUSIONS: Memory and executive functions alterations impact similarly on the CADL in both amnestic multi-domain MCI and incipient Alzheimer's disease. Given the continuum that exists between both conditions, we conclude that CADL impairment may be an important early step in the evolution towards Alzheimer's disease from amnestic multi-domain MCI.

Motor Improvement of Skilled Forelimb Use Induced by Treatment with Growth Hormone and Rehabilitation Is Dependent on the Onset of the Treatment after Cortical Ablation.

We previously demonstrated that the administration of GH immediately after severe motor cortex injury, in rats, followed by rehabilitation, improved the functionality of the affected limb and reexpressed nestin in the contralateral motor cortex. Here, we analyze whether these GH effects depend on a time window after the injury and on the reexpression of nestin and actin. Injured animals were treated with GH (0.15 mg/kg/day) or vehicle, at days 7, 14, and 35 after cortical ablation. Rehabilitation was applied at short and long term (LTR) after the lesion and then sacrificed. Nestin and actin were analyzed by immunoblotting in the contralateral motor cortex. Giving GH at days 7 or 35 after the lesion, but not 14 days after it, led to a remarkable improvement in the functionality of the affected paw. Contralateral nestin and actin reexpression was clearly higher in GH-treated animals, probably because compensatory brain plasticity was established. GH and immediate rehabilitation are key for repairing brain injuries, with the exception of a critical time period: GH treatment starting 14 days after the lesion. Our data also indicate that there is not a clear plateau in the recovery from a brain injury in agreement with our data in human patients.

Does the combination of the MMSE and clock drawing test (mini-clock) improve the detection of mild Alzheimer's disease and mild cognitive impairment?

There is currently a need to develop tools to identify patients with mild AD and mild cognitive impairment (MCI). We determined the validity and reliability of a brief, easily administered cognitive screening battery consisting of fusion of two well-known brief tests (Mini-Mental Status Examination [MMSE] and Clock Drawing Test [CDT]) (Mini-clock) to differentiate between patients with mild AD, MCI, and healthy control subjects. 66 consecutive patients with mild AD, 21 with MCI, and 66 healthy controls seen in a memory clinic setting were compared. Receiver operating characteristic (ROC) curve analysis was used to calculate the cut-off value permitting discrimination between mild AD, MCI, and healthy control subjects. Interrater and test-retest reliability were also assessed. Mean cognitive scores for patients with AD, MCI, and control subjects on all two individual tests were significantly different (for each, p < 0.001). The mean area under the ROC curve for Mini-clock was higher than that obtained with MMSE or CDT in differentiating mild AD from controls (0.973 vs. 0.952 and 0.881, respectively) and MCI from controls (0.855 vs. 0.821 and 0.779, respectively). Test-retest reliability for the Mini-clock was 0.99, meanwhile interrater reliability was 0.87. The mean time to complete the test for all subjects was 8 min and 50 s. The Mini-clock is highly sensitive and specific in the detection of mild AD and reasonably accurate when attempting to separate MCI from health controls. It has a high interrater and test-retest reliability, can be quickly administered, and does not require major training.

Marcador rapd asociado a la resistencia a Fusarium oxysporum en musa / Identification of rapd marker linked to resistance of Musa to Fusarium oxysporum

La marchitez por Fusarium constituye una de las enfermedades más destructivas en Musa, siendo causada por el hongo del suelo Fusarium oxysporum f. sp. cubense. No se cuenta con control químico disponible, siendo la única medida posible la utilización de genotipos resistentes/tolerantes al patógeno. El desarrollo de las técnicas moleculares ha permitido la determinación de marcadores asociados a determinadas condiciones de importancia económica, constituyendo una estrategia de selección rápida, confiable y reproducible que acelera el mejoramiento a través del conocimiento, en estadios tempranos, de la reacción a una característica dada y su interacción con el genotipo. En este estudio se determinó un marcador RAPD asociado a la resistencia de Musa a F. oxysporum utilizando ocho clones susceptibles y diez clones resistentes/tolerantes evaluados en el campo para la reacción a la enfermedad. Se encontró que el patrón obtenido con el iniciador OPK-03 produjo un fragmento de amplificación específico de 485pb presente en los clones susceptibles y ausente en los clones resistentes/tolerantes. El estudio de las relaciones genéticas entre genotipos susceptibles y los resistentes/tolerantes a F. oxysporum, empleando iniciadores RAPD, definió la existencia de un patrón polimorfo asociado a la resistencia a la enfermedad.