Bayesian hierarchical modelling of bacteria growth

Bacterial growth models are commonly used in food safety. Such models permit the prediction of microbial safety and the shelf life of perishable foods. In this paper, we study the problem of modelling bacterial growth when we observe multiple experimental results under identical environmental conditions. We develop a hierarchical version of the Gompertz equation to take into account the possibility of replicated experiments and we show how it can be fitted using a fully Bayesian approach. This approach is illustrated using experimental data from Listeria monocytogenes growth and the results are compared with alternative models. Model selection is undertaken throughout using an appropriate version of the deviance information criterion and the posterior predictive loss criterion. Models are fitted using WinBUGS via R2WinBUGS.Predictive microbiology, Growth models, Gompertz curve, Bayesian hierarchical modelling

A subordinated stochastic process model

We introduce a new stochastic model for non-decreasing processes which can be used to include stochastic variability into any deterministic growth function via subordination. This model is useful in many applications such as growth curves (children’s height, fish length, diameter of trees, etc.) and degradation processes (crack size, wheel degradation, laser light, etc.). One advantage of our approach is the ability to easily deal with data that are irregularly spaced in time or different curves that are observed at different moments of time. With the use of simulations and applications, we examine two approaches to Bayesian inference for our model: the first based on a Gibbs sampler and the second based on approximate Bayesian computation (ABC)

Bayesian modeling of bacterial growth for multiple populations

Bacterial growth models are commonly used for the prediction of microbial safety and the shelf life of perishable foods. Growth is affected by several environmental factors such as temperature, acidity level and salt concentration. In this study, we develop two models to describe bacterial growth for multiple populations under both equal and different environmental conditions. Firstly, a semi-parametric model based on the Gompertz equation is proposed. Assuming that the parameters of the Gompertz equation may vary in relation to the running conditions under which the experiment is performed, we use feed forward neural networks to model the influence of these environmental factors on the growth parameters. Secondly, we propose a more general model which does not assume any underlying parametric form for the growth function. Thus, we consider a neural network as a primary growth model which includes the influencing environmental factors as inputs to the network. One of the main disadvantages of neural networks models is that they are often very difficult to tune which complicates fitting procedures. Here, we show that a simple, Bayesian approach to fitting these models can be implemented via the software package WinBugs. Our approach is illustrated using real experimental Listeria Monocytogenes growth data

Depression, anxiety and delinquency: Results from the Pittsburgh Youth Study

Purpose: The main aim of this research is to investigate to what extent within-individual changes in anxiety and depression are related to within-individual changes in theft and violence. Methods: The youngest sample of the Pittsburgh Youth Study (PYS), a prospective longitudinal survey of 503 boys followed up from age 7 onwards, was analyzed. Depression and anxiety were measured for boys from ages 11 to 22 as were moderate and serious forms of self-reported theft and violence. A hierarchical linear random effects model was used to investigate anxiety and depression as potential causes or outcomes of these forms of delinquency. Results: The results showed that the between-individual correlations were consistently higher than the corresponding within-individual correlations, and provided little evidence to discern the directionality of the potential relationships between depression, anxiety and delinquency. Using a random effects approach, there was limited evidence that prior depression or anxiety was related to later offending, but there was evidence that offending (particularly theft and serious violence) was associated with later increases in anxiety, and to a lesser extent depression. Conclusions: This study indicates that depression and anxiety were outcomes of offending. If replicated, this would suggest that evidence-based interventions which reduced offending would have a desirable influence in reducing depression and anxiety. However, interventions for depression should still form part of responsive interventions. More research which explores within-individual changes in longitudinal studies with repeated measures is needed

Prevalencia de síntomas osteomusculares en trabajadores de un colegio privado de Cali, Colombia.

Work related Musculoskeletal disorders (MSD) are increasingly common worldwide and are the leading cause of occupational morbidity in Colombia. Determining the prevalence of musculoskeletal symptoms in workers is important in order to develop strategies that prevent and reduce their occurrence. Objective: Determine the prevalence of musculoskeletal symptoms (MES) among workers in a private school in Cali, Colombia. Methodology: A descriptive observational study was conducted in 114 workers of a private school in Cali. Sociodemographic data were collected. MES were surveyed with Nordic Questionnaire. Frequencies were compared with X2 test, considering a 0,05 alpha. Results: MES were detected in 73.7% of the participants and 66.7% reported MES in two or more areas with the highest prevalence in spine and lower limbs (39.3%). The prevalence of pain was significantly more frequent in women (P = 0.004). The work group that reported more MES was teachers followed by transportation, and maintenance workers. Conclusions: The prevalence of MES is high among teachers, especially in women. It is important to design strategies in order to reduce their frequency and determine the work related causes and those outside of work.Los desórdenes musculoesqueléticos (DME) relacionados con el trabajo son cada vez más frecuentes en el mundo y actualmente constituyen la primera causa de morbilidad profesional en Colombia. Es importante determinar la prevalencia de síntomas osteomusculares (SOM) en los trabajadores y desarrollar estrategias con el fin de prevenir su ocurrencia. Objetivo:  Determinar la prevalencia de SOM en los trabajadores de un Colegio privado de la ciudad de Cali, Colombia. Metodología: Estudio observacional, descriptivo, realizado en 114 trabajadores de una institución educativa privada. Se recolectaron datos sociodemográficos y laborales a través de una encuesta y se utilizó el Cuestionario Nórdico para el análisis de SOM. Se compararon frecuencias con el test de X2, considerando 0,05 como error alfa. Resultados: El 73.7% de los entrevistados refirieron SOM y de estos el 66.7% refirió dolor en dos o más zonas, con mayor prevalencia en columna y miembros inferiores (39.3%). La prevalencia de dolor fue más frecuente en mujeres que en hombres (P=0.004). El grupo que más reportó SOM fueron los docentes, seguidos por los empleados de transporte y de mantenimiento. Conclusiones: La prevalencia de SOM en docentes es alta, siendo las mujeres las más afectadas. Es importante implementar medidas para disminuir la aparición de SOM, particularmente en columna y miembros inferiores, así como determinar las causas laborales y extralaborales

Deletion of chromosome 11q predicts response to anthracycline-based chemotherapy in early breast cancer

Despite the recent consensus on the eligibility of adjuvant systemic therapy in patients with lymph node–negative breast cancer (NNBC) based on clinicopathologic criteria, specific biological markers are needed to predict sensitivity to the different available therapeutic options.W e examined the feasibility of developing a genomic predictor of chemotherapy response and recurrence risk in 185 patients with NNBC using assembled arrays containing 2,460 bacterial artificial chromosome clones for scanning the genome for DNA copy number changes.Aft er surgery, 90 patients received anthracyclinebased chemotherapy, whereas 95 did not.T amoxifen was administered to patients with hormone receptor–positive tumors. The association of genomic and clinicopathologic data and outcome was computed using Cox proportional hazard models and multiple testing adjustment procedures.Analysis of NNBC genomes revealed a common genomic signature.Specific DNA copy number aberrations were associated with hormonal receptor status, but not with other clinicopathologic variables. In patients treated with chemotherapy, none of the genomic changes were significantly correlated with recurrence.In patients not receiving chemotherapy, deletion of eight bacterial artificial chromosome clones clustered to chromosome 11q was independently associated with relapse (disease-free survival at 10 years F SE, 40% F 14% versus 86% F 6%; P < 0.0001). The 54 patients with deletion of 11q (29%) did not present more aggressive clinicopathologic features than those without 11q loss.The adverse influence of 11q deletion on clinical outcome was confirmed in an independent validation series of 88 patients with NNBC.Our data suggests that patients with NNBC with the 11q deletion might benefit from anthracycline-based chemotherapy despite other clinical, pathologic, or genetic features.However , these initial findings should be evaluated in randomized clinical trials

Evaluating a multicomponent program to improve hypertension control in Guatemala: Study protocol for an effectiveness-implementation cluster randomized trial

Background: Hypertension is a major risk factor for cardiovascular disease (CVD). Despite advances in hypertension prevention and treatment, the proportion of patients who are aware, treated and controlled is low, particularly in low-income and middle-income countries (LMICs). We will evaluate an adapted version of a multilevel and multicomponent hypertension control program in Guatemala, previously proven effective and feasible in Argentina. The program components are: protocol-based hypertension treatment using a standardized algorithm; team-based collaborative care; health provider education; health coaching sessions; home blood pressure monitoring; blood pressure audit; and feedback.Methods: Using a hybrid type 2 effectiveness-implementation design, we will evaluate clinical and implementation outcomes of the multicomponent program in Guatemala over an 18-month period. Through a cluster randomized trial, we will randomly assign 18 health districts to the intervention arm and 18 to enhanced usual care across five departments, enrolling 44 participants per health district and 1584 participants in total. The clinical outcomes are (1) the difference in the proportion of patients with controlled hypertension (< 130/80 mmHg) between the intervention and control groups at 18 months and (2) the net change in systolic and diastolic blood pressure from baseline to 18 months. The context-enhanced Reach, Efficacy, Adoption, Implementation, Maintenance (RE-AIM)/Practical Robust Implementation and Sustainability Model (PRISM) framework will guide the evaluation of the implementation at the level of the patient, provider, and health system. Using a mixed-methods approach, we will evaluate the following implementation outcomes: acceptability, adoption, feasibility, fidelity, adaptation, reach, sustainability, and cost-effectiveness.Discussion: We will disseminate the study findings, and promote scale up and scale out of the program, if proven effective. This study will generate urgently needed data on effective, adoptable, and sustainable interventions and implementation strategies to improve hypertension control in Guatemala and other LMICs.Fil: Paniagua Avila, Alejandra. Columbia University; Estados UnidosFil: Fort, Meredith P.. Institute Of Nutrition Of Central America And Panamá; GuatemalaFil: Glasgow, Russell E.. University of Colorado; Estados UnidosFil: Gulayin, Pablo Elías. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Hernández Galdamez, Diego. institute of Nutrition of Central America and Panamá; GuatemalaFil: Mansilla, Kristyne. institute of Nutrition of Central America and Panamá; GuatemalaFil: Palacios, Eduardo. Ministerio de Salud y Asistencia Social; GuatemalaFil: Peralta, Ana Lucia. Institute of Nutrition of Central America and Panamá ; GuatemalaFil: Roche, Dina. Institute of Nutrition of Central America and Panamá ; GuatemalaFil: Rubinstein, Adolfo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: He, Jiang. University Translational Science Institute; Estados UnidosFil: Ramirez Zea, Manuel. Institute of Nutrition of Central America and Panamá ; GuatemalaFil: Irazola, Vilma. Instituto de Efectividad Clínica y Sanitaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

NADPH Oxidase 5 Is a Pro‐Contractile Nox Isoform and a Point of Cross‐Talk for Calcium and Redox Signaling‐Implications in Vascular Function

Background NADPH Oxidase 5 (Nox5) is a calcium‐sensitive superoxide‐generating Nox. It is present in lower forms and higher mammals, but not in rodents. Nox5 is expressed in vascular cells, but the functional significance remains elusive. Given that contraction is controlled by calcium and reactive oxygen species, both associated with Nox5, we questioned the role of Nox5 in pro‐contractile signaling and vascular function. Methods and Results Transgenic mice expressing human Nox5 in a vascular smooth muscle cell–specific manner (Nox5 mice) and Rhodnius prolixus, an arthropod model that expresses Nox5 endogenoulsy, were studied. Reactive oxygen species generation was increased systemically and in the vasculature and heart in Nox5 mice. In Nox5‐expressing mice, agonist‐induced vasoconstriction was exaggerated and endothelium‐dependent vasorelaxation was impaired. Vascular structural and mechanical properties were not influenced by Nox5. Vascular contractile responses in Nox5 mice were normalized by N‐acetylcysteine and inhibitors of calcium channels, calmodulin, and endoplasmic reticulum ryanodine receptors, but not by GKT137831 (Nox1/4 inhibitor). At the cellular level, vascular changes in Nox5 mice were associated with increased vascular smooth muscle cell [Ca2+]i, increased reactive oxygen species and nitrotyrosine levels, and hyperphosphorylation of pro‐contractile signaling molecules MLC20 (myosin light chain 20) and MYPT1 (myosin phosphatase target subunit 1). Blood pressure was similar in wild‐type and Nox5 mice. Nox5 did not amplify angiotensin II effects. In R. prolixus, gastrointestinal smooth muscle contraction was blunted by Nox5 silencing, but not by VAS2870 (Nox1/2/4 inhibitor). Conclusions Nox5 is a pro‐contractile Nox isoform important in redox‐sensitive contraction. This involves calcium‐calmodulin and endoplasmic reticulum–regulated mechanisms. Our findings define a novel function for vascular Nox5, linking calcium and reactive oxygen species to the pro‐contractile molecular machinery in vascular smooth muscle cells

Estudio de cerámicas arqueológicas. Análisis de fragmentos cerámicos del asentamiento de "la isabela" Santo Domingo, República Dominicana

Se aplican diversas técnicas analíticas a diez fragmentos de cerámicas arqueológicas, para obtener datos sobre la temperatura y la atmósfera de cocción, la mineralogía presente y la deducción de la composición mineralógica de la materia prima y de los desgrasantes utilizados en su manufactura. Estos fragmentos han sido recogidos en el asentamiento de «La Isabela», en Santo Domingo, República Dominicana, llegándose a la conclusión de que cinco de ellas son cerámicos indígenas, otra es también precolombina, pero foránea, y las restantes son españolas o con influencia española.A study of ten fragments of prehistoric pottery retirement in "La Isabela", Republic Dominicana, has been carried out by X- ray diffraction, scanning, thermoqravimeter and differencial thermal analysis methods. The data obtained indicate on the mineralogy, temper and atmosphere of firing. It can also concluded that six the ancient potters were manufacture indigenous and the rest spanish

Hypertension in Guatemala’s Public Primary Care System: A Needs Assessment Using the Health System Building Blocks Framework

Background: Uncontrolled hypertension represents a substantial and growing burden in Guatemala and other low and middle-income countries. As a part of the formative phase of an implementation research study, we conducted a needs assessment to define short- and long-term needs and opportunities for hypertension services within the public health system. Methods: We conducted a multi-method, multi-level assessment of needs related to hypertension within Guatemala’s public system using the World Health Organization’s health system building blocks framework. We conducted semi-structured interviews with stakeholders at national (n = 17), departmental (n = 7), district (n = 25), and community (n = 30) levels and focus groups with patients (3) and frontline auxiliary nurses (3). We visited and captured data about infrastructure, accessibility, human resources, reporting, medications and supplies at 124 health posts and 53 health centers in five departments of Guatemala. We conducted a thematic analysis of transcribed interviews and focus group discussions supported by matrix analysis. We summarized quantitative data observed during visits to health posts and centers. Results: Major challenges for hypertension service delivery included: gaps in infrastructure, insufficient staffing and high turnover, limited training, inconsistent supply of medications, lack of reporting, low prioritization of hypertension, and a low level of funding in the public health system overall. Key opportunities included: prior experience caring for patients with chronic conditions, eagerness from providers to learn, and interest from patients to be involved in managing their health. The 5 departments differ in population served per health facility, accessibility, and staffing. All but 7 health posts had basic infrastructure in place. Enalapril was available in 74% of health posts whereas hydrochlorothiazide was available in only 1 of the 124 health posts. With the exception of one department, over 90% of health posts had a blood pressure monitor. Conclusions: This multi-level multi-method needs assessment using the building blocks framework highlights contextual factors in Guatemala’s public health system that have been important in informing the implementation of a hypertension control trial. Long-term needs that are not addressed within the scope of this study will be important to address to enable sustained implementation and scale-up of the hypertension control approach.Fil: Fort, Meredith P.. University of Colorado; Estados UnidosFil: Mundo, William. University of Colorado; Estados UnidosFil: Paniagua Avila, Alejandra. No especifíca;Fil: Cardona, Sayra. No especifíca;Fil: Figueroa, Juan Carlos. No especifíca;Fil: Hernández Galdamez, Diego. No especifíca;Fil: Mansilla, Kristyne. No especifíca;Fil: Peralta García, Ana. No especifíca;Fil: Roche, Dina. No especifíca;Fil: Palacios, Eduardo Alberto. No especifíca;Fil: Glasgow, Russell E.. University of Colorado; Estados UnidosFil: Gulayin, Pablo Elías. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Irazola, Vilma. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Centro de Investigaciones en Epidemiología y Salud Pública. Instituto de Efectividad Clínica y Sanitaria. Centro de Investigaciones en Epidemiología y Salud Pública; ArgentinaFil: He, Jiang. University of Tulane; Estados UnidosFil: Ramirez Zea, Manuel. No especifíca