Associations of the FTO rs9939609 and the MC4R rs17782313 polymorphisms with type 2 diabetes are modulated by diet, being higher when adherence to the Mediterranean diet pattern is low

[EN]Although the Fat Mass and Obesity (FTO) and Melanocortin-4 Receptor (MC4R) genes have been consistently associated with obesity risk, the association between the obesity-risk alleles with type 2 diabetes is still controversial. In some recent meta-analyses in which significant results have been reported, the associations disappeared after adjustment for body mass index (BMI). However gene-diet interactions with dietary patterns have not been investigated. Our main aim was to analyze whether these associations are modulated by the level of adherence to the Mediterranean Diet (MedDiet).

Knowledge of the patients regarding leprosy and adherence to treatment

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. It is known for its great disfiguring capacity and is considered an extremely serious disease to public health worldwide. The state of Ceará ranks 13th in number of cases of leprosy in Brazil, and fourth in Northeastern region, with an average of 2,149 new cases diagnosed every year. This study aimed to evaluate the knowledge of leprosy patients regarding treatment, and to assess the level of treatment adherence and its possible barriers. The study was conducted in the reference center for dermatology, from September 2010 to October 2010, in Fortaleza, Ceará. The study data were collected by means of a structured interview, along with the Morisky-Green test, in order to assess treatment adherence and barriers to adherence. A total of 70 patients were interviewed, out of whom 66 were new cases. The majority of patients were between 42 and 50 years old, and 37 (52.9%) were male. Most patients were clinically classified as presentingmultibacillary leprosy (80%), and 78.6% of them were from Fortaleza, Brazil. The Morisky-Green test indicated that 62.9% of patients presented a low level of adherence (p < 0.005), despite claiming to aware of the disease risks. However, it was observed that 57.1% of the patients had no difficulty adhering to treatment, while 38.6% reported little difficulty. This study shows that despite the patients claiming to be familiar with leprosy and its treatment, the Morisky-Green test clearly demonstrated that they actually were not aware of the principles of therapy, which is evidenced by the low degree of treatment adherence

Algorithme de reconstruction itératif pour tomographie optique diffuse avec mesures dans le domaine temporel

L'imagerie par tomographie optique diffuse requiert de modéliser la propagation de la lumière dans un tissu biologique pour une configuration optique et géométrique donnée. On appelle cela le problème direct. Une nouvelle approche basée sur la méthode des différences finies pour modéliser numériquement via l'équation de la diffusion (ED) la propagation de la lumière dans le domaine temporel dans un milieu inhomogène 3D avec frontières irrégulières est développée pour le cas de l'imagerie intrinsèque, c'est-à-dire l'imagerie des paramètres optiques d'absorption et de diffusion d'un tissu. Les éléments finis, lourds en calculs, car utilisant des maillages non structurés, sont généralement préférés, car les différences finies ne permettent pas de prendre en compte simplement des frontières irrégulières. L'utilisation de la méthode de blocking-off ainsi que d'un filtre de Sobel en 3D peuvent en principe permettre de surmonter ces difficultés et d'obtenir des équations rapides à résoudre numériquement avec les différences finies. Un algorithme est développé dans le présent ouvrage pour implanter cette approche et l'appliquer dans divers cas puis de la valider en comparant les résultats obtenus à ceux de simulations Monte-Carlo qui servent de référence. L'objectif ultime du projet est de pouvoir imager en trois dimensions un petit animal, c'est pourquoi le modèle de propagation est au coeur de l'algorithme de reconstruction d'images. L'obtention d'images requière la résolution d'un problème inverse de grandes dimensions et l'algorithme est basé sur une fonction objective que l'on minimise de façon itérative à l'aide d'une méthode basée sur le gradient. La fonction objective mesure l'écart entre les mesures expérimentales faites sur le sujet et les prédictions de celles-ci obtenues du modèle de propagation. Une des difficultés dans ce type d'algorithme est l'obtention du gradient. Ceci est fait à l'aide de variables auxiliaire (ou adjointes). Le but est de développer et de combiner des méthodes qui permettent à l'algorithme de converger le plus rapidement possible pour obtenir les propriétés optiques les plus fidèles possible à la réalité capable d'exploiter la dépendance temporelle des mesures résolues en temps, qui fournissent plus d'informations tout autre type de mesure en TOD. Des résultats illustrant la reconstruction d'un milieu complexe comme une souris sont présentés pour démontrer le potentiel de notre approche.

Statin Adherence, Utilisation, and Prescribing Patterns. Improving effectiveness of treatment

Statins are one of the most widely studied and evidence-based medications. Randomised controlled trials have provided convincing evidence on the benefits of statin therapy in preventing cardiovascular events. Despite proven benefits, low costs, and few adverse effects, everyday effectiveness of statins is limited, since adherence to statin therapy is poor. This thesis was conducted as four pharmacoepidemiological studies using register data on statin users in real clinical care. The main purpose of the study was to evaluate prescribing patterns and to discover the lifestyle factors predicting statin nonadherence and discontinuation. This knowledge is essential in order to help physicians to motivate the adherence of their patients to treatment. In Finland, from 1998 to 2004, the number of statin initiators nearly doubled. The discovered channelling of atorvastatin and simvastatin may have affected the treatment outcomes at the public health level. It is possible that money spent on statins in Finland in 1998‒2004 could have been used in a more cost-effective way. In 2015, the percentage of patients receiving reimbursement for statins was 12% of the total population. Thus, it is a major public health and economic challenge to improve statin effectiveness and allocate therapy correctly. Among the participants with cardiovascular comorbidities, risky alcohol use or clustering of lifestyle risks were predictors of nonadherence. In addition, the prevalence of nonadherence to statins increased after retirement among both men and women. This increase in post-retirement nonadherence was highest among those receiving statins for secondary prevention. Discontinuation of statin therapy was predicted by high patient co-payment, and in women, by risky alcohol use. Recognising the predictors of nonadherence to statins is important because nonadherence is associated with an increased risk of adverse cardiovascular outcomes and higher healthcare costs. In conclusion, optimal outcomes in medical therapy require both efficacious medications and adherence to those treatments. When prescribing statins to eligible patients, the physician’s clinical expertise in recognising patients at risk of statin discontinuation and nonadherence, as well as their ability to increase adherence, may have a great effect on public health.

Receptors, sparks and waves in a fire-diffuse-fire framework for calcium release

Calcium ions are an important second messenger in living cells. Indeed calcium signals in the form of waves have been the subject of much recent experimental interest. It is now well established that these waves are composed of elementary stochastic release events (calcium puffs or sparks) from spatially localised calcium stores. The aim of this paper is to analyse how the stochastic nature of individual receptors within these stores combines to create stochastic behaviour on long timescales that may ultimately lead to waves of activity in a spatially extended cell model. Techniques from asymptotic analysis and stochastic phase-plane analysis are used to show that a large cluster of receptor channels leads to a release probability with a sigmoidal dependence on calcium density. This release probability is incorporated into a computationally inexpensive model of calcium release based upon a stochastic generalization of the Fire-Diffuse-Fire (FDF) threshold model. Numerical simulations of the model in one and two dimensions (with stores arranged on both regular and disordered lattices) illustrate that stochastic calcium release leads to the spontaneous production of calcium sparks that may merge to form saltatory waves. Illustrations of spreading circular waves, spirals and more irregular waves are presented. Furthermore, receptor noise is shown to generate a form of array enhanced coherence resonance whereby all calcium stores release periodically and simultaneously.

Directed percolation in a two dimensional stochastic fire-diffuse-fire model

In this paper we establish, from extensive numerical experiments, that the two dimensional stochastic fire-diffuse-fire model belongs to the directed percolation universality class. This model is an idealized model of intracellular calcium release that retains the both the discrete nature of calcium stores and the stochastic nature of release. It is formed from an array of noisy threshold elements that are coupled only by a diffusing signal. The model supports spontaneous release events that can merge to form spreading circular and spiral waves of activity. The critical level of noise required for the system to exhibit a non-equilibrium phase-transition between propagating and non-propagating waves is obtained by an examination of the \textit{local slope} $\delta(t)$ of the survival probability, $\Pi(t) \propto \exp(- \delta(t))$, for a wave to propagate for a time $t$.

Dendritic cable with active spines: a modeling study in the spike-diffuse-spike framework

The spike-diffuse-spike (SDS) model describes a passive dendritic tree with active dendritic spines. Spine-head dynamics is modelled with a simple integrate-and-fire process, whilst communication between spines is mediated by the cable equation. Here we develop a computational framework that allows the study of multiple spiking events in a network of such spines embedded in a simple one-dimensional cable. This system is shown to support saltatory waves as a result of the discrete distribution of spines. Moreover, we demonstrate one of the ways to incorporate noise into the spine-head whilst retaining computational tractability of the model. The SDS model sustains a variety of propagating patterns.

Adherence to antiretroviral therapy and its determinants among persons living with HIV/AIDS in Bayelsa state, Nigeria

Background: A high level of adherence is required to achieve the desired outcomes of antiretroviral therapy. There is paucity of information about adherence to combined antiretroviral therapy in Bayelsa State of southern Nigeria. Objectives: The objectives of the study were to determine the level of adherence to combined antiretroviral therapy among the patients, evaluate the improvement in their immune status and identify reasons for sub-optimal adherence to therapy. Methods: The cross-sectional study involved administration of an adapted and pretested questionnaire to 601 consented patients attending the two tertiary health institutions in Bayesla State, Nigeria: The Federal Medical Centre, Yenagoa and the Niger-Delta University Teaching Hospital Okolobiri. The tool was divided into various sections such as socio-demographic data, HIV knowledge and adherence to combined antiretroviral therapy. Information on the patient's CD4+ T cells count was retrieved from their medical records. Adherence was assessed by asking patients to recall their intake of prescribed doses in the last fourteen days and subjects who had 95-100% of the prescribed antiretroviral drugs were considered adherent. Results: Three hundred and forty eight (57.9%) of the subjects were females and 253 (42.1%) were males. The majority of them, 557 (92.7%) have good knowledge of HIV and combined anti-retroviral therapy with a score of 70.0% and above. A larger proportion of the respondents, 441 (73.4%), had > 95% adherence. Some of the most important reasons giving for missing doses include, “simply forgot” 147 (24.5%), and “wanted to avoid the side-effects of drugs” 33(5.5%). There were remarkable improvements in the immune status of the subjects with an increment in the proportion of the subjects with CD4+ T cells count of greater than 350 cells/mm3 from 33 (5.5%) at therapy initiation to 338 (56.3%) at study period (p<0.0001). Conclusion: The adherence level of 73.4% was low which calls for intervention and improvement. The combined antiretroviral therapy has significantly improved the immune status of the majority of patients which must be sustained. “Simply forgot” was the most important reason for missing doses.

Associations between patient factors and medication adherence: a Jordanian experience

Objective: To explore the effect of patient characteristics and health beliefs on their medication adherence. Methods: Patients (n=167) with chronic conditions (mean age 58.9; SD=13.54, 53% males) were recruited from March 2009- to March 2010 using a cross sectional study design. Data collected included patients’ demographics, medical conditions, medications therapeutic regimen, frequency of physician visits and health beliefs. Patient self-reported adherence to medications was assessed by the researcher using a validated and published scale. Treatment related problems (TRPs) were evaluated for each patient by competent clinical pharmacists. Associations between patient characteristics/health beliefs with adherence were explored. Results: About half of the patients (46.1%) were non-adherent. A significant association was found between lower adherence and higher number of disease states (p<0.001), higher number of medications (p=0.001), and higher number of identified TRPs (p = 0.003). Patient adherence was positively affected by older age, higher educational level, and higher number of physician visits per month, while it was negatively affected by reporting difficulties with getting prescription refills on time. Conclusion: This study identified different factors that may negatively affect adherence, including higher number of medications and disease states, higher number of identified TRPs and inability to getting prescription refills on time. Hence, more care needs to be provided to patients with complex therapeutic regimens in order to enhance adherence.

Alcohol consumption and Mediterranean Diet adherence among health science students in Spain: the DiSA-UMH Study

Objective: To describe the association between consumption of different alcoholic beverages and adherence to the Mediterranean diet. Methods: A cross-sectional analysis was conducted of the baseline data of the DiSA-UMH study, an ongoing cohort study with Spanish health science students (n = 1098) aged 17-35 years. Dietary information was collected by a validated 84-item food frequency questionnaire. Participants were grouped into non-drinkers, exclusive beer and/or wine drinkers and drinkers of all types of alcoholic beverages. Mediterranean diet adherence was determined by using a modification of the relative Mediterranean Diet Score (rMED; score range: 0-16) according to consumption of 8 dietary components. We performed multiple linear and multinomial regression analyses. Results: The mean alcohol consumption was 4.3 g/day (SD: 6.1). A total of 19.5%, 18.9% and 61.6% of the participants were non-drinkers, exclusive beer and/or wine drinkers and drinkers of all types of alcoholic beverages, respectively. Participants who consumed beer and/or wine exclusively had higher rMED scores than non-drinkers (β: 0.76, 95%CI: 0.25-1.27). Drinkers of all types of alcoholic beverages had similar rMED scores to non-drinkers. Non-drinkers consumed less fish and more meat, whereas drinkers of all types of alcoholic beverages consumed fewer fruits, vegetables and more meat than exclusive beer and/or wine drinkers. Conclusions: The overall alcohol consumption among the students in our study was low-to-moderate. Exclusive beer and/or wine drinkers differed regarding the Mediterranean diet pattern from non-drinkers and drinkers of all types of alcohol. These results show the need to properly adjust for diet in studies of the effects of alcohol consumption.

Spatio-temporal filtering properties of a dendritic cable with active spines: a modeling study in the spike-diffuse-spike framework

The spike-diffuse-spike (SDS) model describes a passive dendritic tree with active dendritic spines. Spine-head dynamics is modeled with a simple integrate-and-fire process, whilst communication between spines is mediated by the cable equation. In this paper we develop a computational framework that allows the study of multiple spiking events in a network of such spines embedded on a simple one-dimensional cable. In the first instance this system is shown to support saltatory waves with the same qualitative features as those observed in a model with Hodgkin-Huxley kinetics in the spine-head. Moreover, there is excellent agreement with the analytically calculated speed for a solitary saltatory pulse. Upon driving the system with time varying external input we find that the distribution of spines can play a crucial role in determining spatio-temporal filtering properties. In particular, the SDS model in response to periodic pulse train shows a positive correlation between spine density and low-pass temporal filtering that is consistent with the experimental results of Rose and Fortune [1999, Mechanisms for generating temporal filters in the electrosensory system. The Journal of Experimental Biology 202, 1281-1289]. Further, we demonstrate the robustness of observed wave properties to natural sources of noise that arise both in the cable and the spine-head, and highlight the possibility of purely noise induced waves and coherent oscillations.

Barriers to and facilitators of older adult’s adherence to health recommendations: Towards an EngAging two-way health communication

Non-adherence to health recommendations (e.g. medical prescriptions) presents potential costs for healthcare, which could be prevented or mitigated. This is often attributed to a person’s rational choice, to not adhere. However, this may also be determined by individual and contextual factors implied in the recommendations communication process. In accordance, this chapter focuses specifically on barriers to and facilitators of adherence to recommendations and engagement with the healthcare process, particularly concerning the communication between health professionals and patients. For this, the authors present examples of engagement increment through different degrees of participation, from a one-way/directive towards a two-way/engaging communication process. This focuses specifically on a vulnerable population group with increasing healthcare needs: older adults. Future possibilities for two-way engaging communications are discussed, aimed at promoting increased adherence to health recommendations and people’s self-regulation of their own health.

Information and Communication Technologies (ICT) to Improve Prescription Appropriateness and Therapy Adherence in the Multi-morbid Elderly

Multimorbidity patients pose severe challenges to which information and communication technology (ICT) can help patients and doctors to answer with effective and efficient care.

Knowledge of the patients regarding leprosy and adherence to treatment

Leprosy is a chronic infectious disease caused by Mycobacterium leprae. It is known for its great disfiguring capacity and is considered an extremely serious disease to public health worldwide. The state of Ceará ranks 13th in number of cases of leprosy in Brazil, and fourth in Northeastern region, with an average of 2,149 new cases diagnosed every year. This study aimed to evaluate the knowledge of leprosy patients regarding treatment, and to assess the level of treatment adherence and its possible barriers. The study was conducted in the reference center for dermatology, from September 2010 to October 2010, in Fortaleza, Ceará. The study data were collected by means of a structured interview, along with the Morisky-Green test, in order to assess treatment adherence and barriers to adherence. A total of 70 patients were interviewed, out of whom 66 were new cases. The majority of patients were between 42 and 50 years old, and 37 (52.9%) were male. Most patients were clinically classified as presentingmultibacillary leprosy (80%), and 78.6% of them were from Fortaleza, Brazil. The Morisky-Green test indicated that 62.9% of patients presented a low level of adherence (p < 0.005), despite claiming to aware of the disease risks. However, it was observed that 57.1% of the patients had no difficulty adhering to treatment, while 38.6% reported little difficulty. This study shows that despite the patients claiming to be familiar with leprosy and its treatment, the Morisky-Green test clearly demonstrated that they actually were not aware of the principles of therapy, which is evidenced by the low degree of treatment adherence

A study of electrochemical transport and diffuse charge dynamics using a Langevin equation

This thesis aims to develop new numerical and computational tools to study electrochemical transport and diffuse charge dynamics at small scales. Previous efforts at modeling electrokinetic phenomena at scales where the noncontinuum effects become significant have included continuum models based on the Poisson-Nernst-Planck equations and atomic simulations using molecular dynamics algorithms. Neither of them is easy to use or conducive to electrokinetic transport modeling in strong confinement or over long time scales. This work introduces a new approach based on a Langevin equation for diffuse charge dynamics in nanofluidic devices, which incorporates features from both continuum and atomistic methods. The model is then extended to include steric effects resulting from finite ion size, and applied to the phenomenon of double layer charging in a symmetric binary electrolyte between parallel-plate blocking electrodes, between which a voltage is applied. Finally, the results of this approach are compared to those of the continuum model based on the Poisson-Nernst-Planck equations.