Does APOE genotype moderate the relationship between physical activity, brain health and dementia risk? A systematic review.

INTRODUCTION: For decades, researchers have tried to understand the moderating effect of APOE ε4 carriage on the relationship between physical activity (PA), brain health and dementia risk. However, this field has produced inconsistent findings. METHOD: We conducted a systematic review of the literature, searching for observational and interventional studies examining the effect of APOE ε4 carriage on the relationships between PA, dementia risk and different markers of brain health. RESULTS: Observational studies using dementia risk as a primary outcome measure generally found that in shorter follow-up periods (up to 10 years) both APOE ε4 carriers and non-carriers benefit from PA, although longer follow-ups showed mixed results. In neuroimaging studies, mainly carriers or both groups showed benefits. Additionally, the association between PA and amyloid burden was more evident among carriers. Overall, studies with greater samples of active APOE ε4 carriers are more likely to report benefits within this group in terms of lower dementia risk and reduced brain pathology. DISCUSSION: Although we have identified some patterns for the modulating effect of APOE ε4 on PA and dementia or brain pathology, the available data is, overall, inconclusive. Heterogeneity in study design, methodology, and outcomes blur the ability to detect clear associations.

The relationship between physical activity, apolipoprotein E ε4 carriage, and brain health.

BACKGROUND: Neuronal hyperexcitability and hypersynchrony have been described as key features of neurophysiological dysfunctions in the Alzheimer's disease (AD) continuum. Conversely, physical activity (PA) has been associated with improved brain health and reduced AD risk. However, there is controversy regarding whether AD genetic risk (in terms of APOE ε4 carriage) modulates these relationships. The utilization of multiple outcome measures within one sample may strengthen our understanding of this complex phenomenon. METHOD: The relationship between PA and functional connectivity (FC) was examined in a sample of 107 healthy older adults using magnetoencephalography. Additionally, we explored whether ε4 carriage modulates this association. The correlation between FC and brain structural integrity, cognition, and mood was also investigated. RESULTS: A relationship between higher PA and decreased FC (hyposynchrony) in the left temporal lobe was observed among all individuals (across the whole sample, in ε4 carriers, and in ε4 non-carriers), but its effects manifest differently according to genetic risk. In ε4 carriers, we report an association between this region-specific FC profile and preserved brain structure (greater gray matter volumes and higher integrity of white matter tracts). In this group, decreased FC also correlated with reduced anxiety levels. In ε4 non-carriers, this profile is associated with improved cognition (working and episodic memory). CONCLUSIONS: PA could mitigate the increase in FC (hypersynchronization) that characterizes preclinical AD, being beneficial for all individuals, especially ε4 carriers.

A nutritional supplement containing lactoferrin stimulates the immune system, extends lifespan, and reduces amyloid ß peptide toxicity in Caenorhabditis elegans.

Lactoferrin is a highly multifunctional glycoprotein involved in many physiological functions, including regulation of iron absorption and immune responses. Moreover, there is increasing evidence for neuroprotective effects of lactoferrin. We used Caenorhabditis elegans as a model to test the protective effects, both on phenotype and transcriptome, of a nutraceutical product based on lactoferrin liposomes. In a dose-dependent manner, the lactoferrin-based product protected against acute oxidative stress and extended lifespan of C. elegans N2. Furthermore, Paralysis of the transgenic C. elegans strain CL4176, caused by Aß1-42 aggregates, was clearly ameliorated by treatment. Transcriptome analysis in treated nematodes indicated immune system stimulation, together with enhancement of processes involved in the oxidative stress response. The lactoferrin-based product also improved the protein homeostasis processes, cellular adhesion processes, and neurogenesis in the nematode. In summary, the tested product exerts protection against aging and neurodegeneration, modulating processes involved in oxidative stress response, protein homeostasis, synaptic function, and xenobiotic metabolism. This lactoferrin-based product is also able to stimulate the immune system, as well as improving reproductive status and energy metabolism. These findings suggest that oral supplementation with this lactoferrin-based product could improve the immune system and antioxidant capacity. Further studies to understand the molecular mechanisms related with neuronal function would be of interest.

Microneedling dilates the follicular infundibulum and increases transfollicular absorption of liposomal sepia melanin.

Encapsulation of chemicals in liposomes and microneedling are currently used techniques to enhance the penetration of several substances through skin and hair. In this study, we apply a liposomal melanin-fluorescein compound to an ex vivo model of human skin, using a new electrical microneedling device (Nanopore turbo roller). The product was applied by hand massage (A) or with the assistance of the electrical roller for 2 minutes (B). An additional test was performed free of product and with only the E-roller (C). Histological changes and product absorption were evaluated by optical and fluorescent microscopy 60 and 90 minutes after the treatment. Site B showed larger deposits of melanin-fluorescein at superficial and deep levels of hair structures in comparison to site A. Light, epidermal deposits of the melanin-fluorescein complex were also observed. Sites B and C showed a significant widening (47%) of the follicular infundibulum which could explain the increased penetration of the formulation. Microneedling also removed the scales and sebum residues in the neighborhood of the infundibulum. Targeting hair follicles with melanin may be useful to dye poorly pigmented hairs, improving laser hair removal. The procedure accelerates the delivery of melanin into hair structures allowing an even absorption, larger pigment deposits, and deeper penetration of the formulation into the hair.

Selective attention and facial expression recognition in patients with Parkinson's disease.

Parkinson's disease (PD) has been associated with facial expression recognition difficulties. However, this impairment could be secondary to the one produced in other cognitive processes involved in recognition, such as selective attention. This study investigates the influence of two selective attention components (inhibition and visual search) on facial expression recognition in PD. We compared facial expression and non-emotional stimuli recognition abilities of 51 patients and 51 healthy controls, by means of an adapted Stroop task, and by "The Face in the Crowd" paradigm, which assess Inhibition and Visual Search abilities, respectively. Patients scored worse than controls in both tasks with facial expressions, but not with the other nonemotional stimuli, indicating specific emotional recognition impairment, not dependent on selective attention abilities. This should be taken into account in patients' neuropsychological assessment given the relevance of emotional facial expression for social communication in everyday settings.

Discrimination and categorization of emotional facial expressions and faces in Parkinson's disease.

Our objective was to compare the ability to discriminate and categorize emotional facial expressions (EFEs) and facial identity characteristics (age and/or gender) in a group of 53 individuals with Parkinson's disease (PD) and another group of 53 healthy subjects. On the one hand, by means of discrimination and identification tasks, we compared two stages in the visual recognition process that could be selectively affected in individuals with PD. On the other hand, facial expression versus gender and age comparison permits us to contrast whether the emotional or non-emotional content influences the configural perception of faces. In Experiment I, we did not find differences between groups, either with facial expression or age, in discrimination tasks. Conversely, in Experiment II, we found differences between the groups, but only in the EFE identification task. Taken together, our results indicate that configural perception of faces does not seem to be globally impaired in PD. However, this ability is selectively altered when the categorization of emotional faces is required. A deeper assessment of the PD group indicated that decline in facial expression categorization is more evident in a subgroup of patients with higher global impairment (motor and cognitive). Taken together, these results suggest that the problems found in facial expression recognition may be associated with the progressive neuronal loss in frontostriatal and mesolimbic circuits, which characterizes PD.

Is a neutral expression also a neutral stimulus? A study with functional magnetic resonance.

Although neutral faces do not initially convey an explicit emotional message, it has been found that individuals tend to assign them an affective content. Moreover, previous research has shown that affective judgments are mediated by the task they have to perform. Using functional magnetic resonance imaging in 21 healthy participants, we focus this study on the cerebral activity patterns triggered by neutral and emotional faces in two different tasks (social or gender judgments). Results obtained, using conjunction analyses, indicated that viewing both emotional and neutral faces evokes activity in several similar brain areas indicating a common neural substrate. Moreover, neutral faces specifically elicit activation of cerebellum, frontal and temporal areas, while emotional faces involve the cuneus, anterior cingulated gyrus, medial orbitofrontal cortex, posterior superior temporal gyrus, precentral/postcentral gyrus and insula. The task selected was also found to influence brain activity, in that the social task recruited frontal areas while the gender task involved the posterior cingulated, inferior parietal lobule and middle temporal gyrus to a greater extent. Specifically, in the social task viewing neutral faces was associated with longer reaction times and increased activity of left dorsolateral frontal cortex compared with viewing facial expressions of emotions. In contrast, in the same task emotional expressions distinctively activated the left amygdale. The results are discussed taking into consideration the fact that, like other facial expressions, neutral expressions are usually assigned some emotional significance. However, neutral faces evoke a greater activation of circuits probably involved in more elaborate cognitive processing.

Perception and recall of faces and facial expressions following temporal lobectomy.

The perception of and memory for faces, with or without emotional content, were studied in 43 patients with temporal lobe epilepsy who had undergone unilateral resection of the hippocampus and the amygdala and in 43 healthy participants for comparison. Each participant performed four tasks from the Florida Affect Battery (Facial Discrimination, Affect Discrimination, Affect Naming, Affect Selection) and two memory tasks (in one case of a face and in the other of a facial expression). Findings indicated that, although patients with unilateral temporal lobectomy (right or left) showed no difficulty in discriminating faces, they were not as good at remembering faces. Also, patients who had had a left temporal lobectomy showed impairment in discriminating facial expressions, in the memory of a facial expression and/or in naming facial expressions.

Enfermedad de Bowen perianal / Bowen's disease of the anus

La Enfermedad de Bowen Perianal (EBP) es una entidad rara de curso crónico, poco agresiva, pero con un riesgo real aunque bajo de desarrollar cáncer escamoso invasor. Afecta predominante mujeres mayores de 50 años. Con mucha frecuencia se asocia con infección por papiloma virus en región anal y genital, lo que podría ser el factor de riesgo para el desarrollo de la neoplasia maligna. El tratamiento actualmente aceptado es la resección local amplia (RLA) con o sin injerto de piel

Cancer colorrectal temprano: enfoque y manejo / Early colorrectal cancer: approach and treatment

En la actualidad, el cáncer colorrectal temprano (CCT) constituye sólo el 10 por ciento del total de cánceres colorrectales diagnosticados, pero se espera que esta proporción aumente de manera importante con los programas de tamizaje en desarrollo además del perfeccionamiento en las técnicas de diagnóstico y tratamiento endoscópico. Comparando el espectro histopatológico del CCT desde la perspectiva occidental y oriental, se de.ne el enfoque anatomopatológico de estas lesiones, describiendo su historia natural y los nuevos sistemas de clasi.cación y estadi.cación, orientados todos a establecer el grado de invasión local y predecir la probabilidad de metástasis ganglionares. Es así como, con el conocimiento y el análisis integral de las variables biológicas, histológicas, endoscópicas y clínicas, se logra establecer un pronóstico que permite instaurar la estrategia terapéutica más adecuada para cada individuo