Motor, Cognitive, and Behavioral Impairment in TLR3 and TLR9 Deficient Male Mice: Insights into the Non-Immunological Roles of Toll-Like Receptors

BACKGROUND

Toll-like receptors (TLRs) play a critical role in initiating the innate immune response to infection or injury. Recent studies have uncovered their intriguing functions as moonlighting proteins involved in various biological processes, including development, learning, and memory. However, the specific functions of individual TLRs are still largely unknown.

AIMS

We investigated the effects of TLR3 and TLR9 receptor deficiency on motor, cognitive, and behavioral functions during development using genetically modified male mice of different ages.

METHODS

We evaluated the motor coordination, anxiety-like behavior, spatial learning, and working memory of male mice lacking the TLR3 and TLR9 genes at different ages (two, four, six, and eight months) using the rotarod, open field, water maze, and T-maze tests.

RESULTS

We observed that the deletion of either TLR3 or TLR9 resulted in impaired motor performance. Furthermore, young TLR3-deficient mice exhibited reduced anxiety-like behavior and spatial learning deficits; however, their working memory was unaffected. In contrast, young TLR9-knockout mice showed hyperactivity and a tendency toward decreased working memory.

CONCLUSIONS

These findings provide valuable insights into the broader roles of the TLR system beyond the innate immune response, revealing its involvement in pathways associated with the central nervous system. Importantly, our results establish a strong association between the endosomal receptors TLR3 and TLR9 and the performance of motor, cognitive, and behavioral tasks that change over time. This study contributes to the growing body of research on the multifaceted functions of TLRs and enhances our understanding of their participation in non-immune-related processes.

Effect of Propranolol on Motor Cortex Excitability in Essential Tremor: An Exploratory Study

Background

Essential tremor, the world's most prevalent movement disorder, lacks a clear understanding of its pathophysiology. Propranolol, a non-specific beta-blocker capable of crossing the blood-brain barrier, is a primary choice for essential tremor treatment. While its tremor-reducing effects are generally attributed to peripheral actions, various uses hint at central adrenergic effects. Nevertheless, propranolol's precise impact on the central nervous system in essential tremor subjects remains unexplored.

Methods

In this study, we employed transcranial magnetic stimulation to assess the influence of propranolol on the excitability of the primary motor cortex (M1) in patients with essential tremor, compared to an age- and sex-matched control group. Cortical excitability parameters were measured following placebo and propranolol administration, encompassing resting and active motor thresholds, motor evoked potential characteristics, cortical silent period, and the input/output curve.

Results

Distinct effects were observed across the two cortical hemispheres. Essential tremor patients displayed inhibition of the left M1 cortex and heightened excitability in the right M1 cortex four hours after propranolol administration, but not following placebo.

Conclusions

These findings suggest potential differential noradrenergic excitatory and inhibitory modulation. However, comprehensive understanding necessitates further investigations, including left-handed participants and more diverse essential tremor subpopulations. This study underscores the need for continued exploration to unravel propranolol's complex effects on motor cortex excitability in essential tremor.

[Guide to write a scientific article]

Publishing a scientific article is challenging for early-career researchers and clinicians. Success is not solely determined by robust research methods, but also by clear and logical presentation of results. Without clear communication, disruptive findings can be overlooked. A well-structured manuscript leads the reader logically from the introduction to the conclusion. Maintaining a consistent narrative ensures lasting impact. In this paper, we provide practical guidelines for drafting an effective scientific manuscript. Carefully crafted articles increase the chance of acceptance and improve comprehension among diverse specialists. We emphasize the importance of presenting a clear, relevant, and engaging story within a structured framework, highly valued by editors, reviewers, and readers.

Differential expression of PSMC4, SKP1, and HSPA8 in Parkinson's disease: insights from a Mexican mestizo population

Parkinson's disease (PD) is a complex neurodegenerative condition characterized by alpha-synuclein aggregation and dysfunctional protein degradation pathways. This study investigates the differential gene expression of pivotal components (UBE2K, PSMC4, SKP1, and HSPA8) within these pathways in a Mexican-Mestizo PD population compared to healthy controls. We enrolled 87 PD patients and 87 controls, assessing their gene expression levels via RT-qPCR. Our results reveal a significant downregulation of PSMC4, SKP1, and HSPA8 in the PD group (p = 0.033, p = 0.003, and p = 0.002, respectively). Logistic regression analyses establish a strong association between PD and reduced expression of PSMC4, SKP1, and HSPA8 (OR = 0.640, 95% CI = 0.415-0.987; OR = 0.000, 95% CI = 0.000-0.075; OR = 0.550, 95% CI = 0.368-0.823, respectively). Conversely, UBE2K exhibited no significant association or expression difference between the groups. Furthermore, we develop a gene expression model based on HSPA8, PSMC4, and SKP1, demonstrating robust discrimination between healthy controls and PD patients. Notably, the model's diagnostic efficacy is particularly pronounced in early-stage PD. In conclusion, our study provides compelling evidence linking decreased gene expression of PSMC4, SKP1, and HSPA8 to PD in the Mexican-Mestizo population. Additionally, our gene expression model exhibits promise as a diagnostic tool, particularly for early-stage PD diagnosis.

A comprehensive guide to BCI-based stroke neurorehabilitation interventions

Brain-Computer Interfaces (BCIs) offer the potential to facilitate neurorehabilitation in stroke patients by decoding user intentions from the central nervous system, thereby enabling control over external devices. Despite their promise, the diverse range of intervention parameters and technical challenges in clinical settings have hindered the accumulation of substantial evidence supporting the efficacy and effectiveness of BCIs in stroke rehabilitation. This article introduces a practical guide designed to navigate through these challenges in conducting BCI interventions for stroke rehabilitation. Applicable regardless of infrastructure and study design limitations, this guide acts as a comprehensive reference for executing BCI-based stroke interventions. Furthermore, it encapsulates insights gleaned from administering hundreds of BCI rehabilitation sessions to stroke patients.•Presents a comprehensive methodology for implementing BCI-based upper extremity therapy in stroke patients.•Provides detailed guidance on the number of sessions, trials, as well as the necessary hardware and software for effective intervention.

Methodological approach for assessing motor cortical excitability changes with single-pulse transcranial magnetic stimulation

Transcranial Magnetic Stimulation (TMS) serves as a crucial tool in evaluating motor cortex excitability by applying short magnetic pulses to the skull, inducing neuron depolarization in the cerebral cortex through electromagnetic induction. This technique leads to the activation of specific skeletal muscles recorded as Motor-Evoked Potentials (MEPs) through electromyography. Although various methodologies assess cortical excitability with TMS, measuring MEP amplitudes offers a straightforward approach, especially when comparing excitability states pre- and post-interventions designed to alter cortical excitability. Despite TMS's widespread use, the absence of a standardized procedure for such measurements in existing literature hinders the comparison of results across different studies. This paper proposes a standardized procedure for assessing changes in motor cortical excitability using single-pulse TMS pre- and post-intervention. The recommended approach utilizes an intensity equating to half of the MEP's maximum amplitude, thereby ensuring equal likelihood of amplitude increase or decrease, providing a consistent basis for future studies and facilitating meaningful comparisons of results.•A method for assessing changes in motor cortical excitability using single-pulse TMS before and after a specified intervention.•We recommend using an intensity equal to half of the MEP's maximum amplitude during evaluations to objectively assess motor cortical excitability changes post-intervention.

Remote Assessment of Parkinson's Disease Patients Amidst the COVID-19 Lockdown in Mexico

The COVID-19 pandemic introduced unprecedented challenges in managing patients with Parkinson's disease (PD) due to disruptions in healthcare services and the need for social distancing. Understanding the effects of COVID-19 on PD symptoms is crucial for optimizing patient care. We conducted a comprehensive analysis of the data obtained during the period of COVID-19 lockdown, comparing it with analogous timeframes in 2018 and 2019. Our objective was to examine the influence of this unique circumstance on both motor and non-motor symptoms in patients with PD. Telemedicine was employed to assess symptoms using the Movement Disorder Society-sponsored Unified Parkinson's Disease Rating Scale (MDS-UPDRS). Our findings revealed a notable worsening of symptoms, evidenced by a significant increase in the total MDS-UPDRS score. Specifically, there was an increase in Part III scores, reflecting changes in motor function. However, no differences were observed in Parts I or II, which pertain to non-motor symptoms. Additionally, patient satisfaction and the feasibility of telemedicine consultations were high, highlighting the efficacy of this alternative approach during the pandemic. The COVID-19 pandemic had a discernible impact on PD symptoms, with a significant worsening of motor symptoms observed during the lockdown period. Telemedicine was a valuable tool for remote assessment and follow-up, ensuring continuity of care for individuals with PD in the face of pandemic-related challenges.

Two-stage reinforcement learning task predicts psychological traits

External sources of information influence human actions. However, psychological traits (PTs), considered internal variables, also play a crucial role in decision making. PTs are stable across time and contexts and define the set of behavioral repertoires that individuals express. Here, we explored how multiple metrics of adaptive behavior under uncertainty related to several PTs. Participants solved a reversal-learning task with volatile contingencies, from which we characterized a detailed behavioral profile based on their response sequences. We then tested the relationship between this multimetric behavioral profile and scores obtained from self-report psychological questionnaires. The PT measurements were based on the Hierarchical Taxonomy Of Psychopathology (HiTOP) model. By using multiple linear regression models (MLRMs), we found that the learning curves predicted important differences in the PTs and task response times. We confirmed the significance of these relationships by using random permutations of the predictors of the MLRM. Therefore, the behavioral profile configurations predicted the PTs and served as a "fingerprint" to identify participants with a high certainty level. We discuss briefly how this characterization and approach could contribute to better nosological classifications.

Transcranial Focal Electrical Stimulation Modifies Biogenic Amines' Alterations Induced by 6-Hydroxydopamine in Rat Brain

Transcranial focal stimulation (TFS) is a non-invasive neuromodulation strategy with neuroprotective effects. On the other hand, 6-hidroxidopamine (6-OHDA) induces neurodegeneration of the nigrostriatal system producing modifications in the dopaminergic, serotoninergic, and histaminergic systems. The present study was conducted to test whether repetitive application of TFS avoids the biogenic amines' changes induced by the intrastriatal injection of 6-OHDA. Experiments were designed to determine the tissue content of dopamine, serotonin, and histamine in the brain of animals injected with 6-OHDA and then receiving daily TFS for 21 days. Tissue content of biogenic amines was evaluated in the cerebral cortex, hippocampus, amygdala, and striatum, ipsi- and contralateral to the side of 6-OHDA injection. Results obtained were compared to animals with 6-OHDA, TFS alone, and a Sham group. The present study revealed that TFS did not avoid the changes in the tissue content of dopamine in striatum. However, TFS was able to avoid several of the changes induced by 6-OHDA in the tissue content of dopamine, serotonin, and histamine in the different brain areas evaluated. Interestingly, TFS alone did not induce significant changes in the different brain areas evaluated. The present study showed that repetitive TFS avoids the biogenic amines' changes induced by 6-OHDA. TFS can represent a new therapeutic strategy to avoid the neurotoxicity induced by 6-OHDA.

Prognosis of stroke upper limb recovery with physiological variables using regression tree ensembles

Objective.This study assesses upper limb recovery prognosis after stroke with solely physiological information, which can provide an objective estimation of recovery.Approach.Clinical recovery was forecasted using EEG-derived Event-Related Desynchronization/Synchronization and coherence, in addition to Transcranial Magnetic Stimulation elicited motor-evoked potentials and upper limb grip and pinch strength. A Regression Tree Ensemble predicted clinical recovery of a stroke database (n= 10) measured after a two-month intervention with the Fugl-Meyer Assessment for the Upper Extremity (FMA-UE) and the Action Research Arm Test (ARAT).Main results.There were no significant differences between predicted and actual outcomes with FMA-UE (p= 0.29) and ARAT (p= 0.5). Median prediction error for FMA-UE and ARAT were of 0.3 (IQR = 6.2) and 3.4 (IQR = 9.4) points, respectively. Predictions with the most pronounced errors were due to an underestimation of high upper limb recovery. The best features for FMA-UE prediction included mostly beta activity over the sensorimotor cortex. Best ARAT prediction features were cortical beta activity, corticospinal tract integrity of the unaffected hemisphere, and upper limb strength.Significance.Results highlighted the importance of measuring cortical activity related to motor control processes, the unaffected hemisphere's integrity, and upper limb strength for prognosis. It was also implied that stroke upper limb recovery prediction is feasible using solely physiological variables with a Regression Tree Ensemble, which can also be used to analyze physiological relationships with recovery.

α-syn and SNP rs356219 as a potential biomarker in blood for Parkinson's disease in Mexican Mestizos

Clinical criteria diagnose Parkinson's disease (PD), therefore, it is crucial to find biological elements that could support diagnosis or even act as prognostic tools of PD. The SNCA gene codifies a protein called α - synuclein; several studies associate genetic and biochemical factors of SNCA with PD, including transcript and plasmatic protein levels, however, contradictory evidence indicates inconclusive results. We aim to compare SNCA mRNA expression, plasmatic α-syn protein and rs356219 SNP between PD cases and a control group, and to identify a potential biomarker in Mexican mestizos', focusing on these three components determined in blood. We included 88 PD patients and 88 age-matched controls. We observed higher α-syn protein and decreased SNCA mRNA levels in PD subjects, compared to control group (p = 0.044 and p < 0.001, respectively). A statistically significant difference was found in allelic and genotypic frequencies of SNP rs356219 between PD patients and normal subjects (p = 0.006 and p = 0.023, respectively). Logistic regression analysis determined as optimal predictors of PD the GG genotype of SNP rs356219 (OR 2.49; p = 0.006) in a recessive model and α-syn protein (OR 1.057; p = 0.033). Furthermore, the G allele of SNP rs356219 was associated with higher plasmatic α-syn and mRNA levels in PD subjects. The receiver operating curves (ROC) distinguished PD from healthy controls with good sensitivity and specificity considering the plasmatic α-syn protein (AUC = 0.693, Sensitivity = 66.7 %, Specificity = 63.9 %) or a predictive probability of plasmatic α-syn protein and SNP rs356219 in a single model (AUC = 0.692, Sensitivity = 62.3 %, Specificity = 62.5 %). The performance of this classifier model in PD at early stage (n = 31) increase the discriminant power in both, plasmatic α-syn protein (AUC = 0.779, Sensitivity = 72.7 %, Specificity = 73.9 %) and predictive probability (AUC = 0.707, Sensitivity = 63.6 %, Specificity = 62.5 %). We propose that α-syn protein and SNP rs356219 together may work as a good signature of PD, and they can be suggested as a non-invasive biomarker of PD risk.

Toxoplasma gondii infection and multiple sclerosis: An age- and a gender-matched case-control seroprevalence study

The link between Toxoplasma gondii infection and multiple sclerosis remains controversial. In the present study, we aimed to determine the association between T.gondii seropositivity and multiple sclerosis. Using an age- and gender-matched case-control study, we studied 45 patients who had multiple sclerosis attended in two public hospitals and 225 control subjects without this disease and other neurological disorders in Durango City, Mexico. Serum samples of cases and controls were analyzed for detection of anti-Toxoplasma IgG using a commercially available enzyme-linked immunoassay. One (2.22%) of the 45 patients with multiple sclerosis, and 15 (6.67%) of the 225 control subjects without this disease were seropositive for anti-T. gondii IgG antibodies. No statistically significant difference (OR = 0.31; 95% CI: 0.04–2.47; P = 0.48) in seroprevalence of anti-T. gondii IgG antibodies between cases and controls was found. The frequency of T. gondii seropositivity did not vary among cases and controls about sex or age groups. Results of this study do not support an association between seropositivity to T. gondii and multiple sclerosis. However, additional research with larger sample sizes to confirm this lack of association should be conducted.

Different Food Odors Control Brain Connectivity in Impulsive Children

BACKGROUND

Impulsivity is a complex multi-dimensional combination of behaviors which include: ineffective impulse control, premature decision-making and inability to delay gratification.

OBJECTIVE

The aim of this work was to explore how food odor perception and its emotional value is affected in impulsive children.

METHODS

Here we compared two cohorts of impulsive and control children with ages between 10 and 16 years. Both groups underwent a functional magnetic resonance imaging experiment, in which foodrelated odor-cues were presented to all of them.

RESULTS

Differences in regions of blood oxygen level dependent activation, as well as connectivity, were calculated. Activations were significant for all odors in the impulsive group in the temporal lobe, cerebellum, supplementary motor area, frontal cortex, medial cingulate cortex, insula, precuneus, precentral, para-hippocampal and calcarine cortices.

CONCLUSION

Connectivity results showed that the expected emotional reward, based on odor perceived and processed in temporal lobes, was the main cue driving responses of impulsive children. This was followed by self-consciousness, the sensation of interaction with the surroundings and feelings of comfort and happiness, modulated by the precuneus together with somatosensory cortex and cingulum. Furthermore, reduced connectivity to frontal areas as well as to other sensory integration areas (piriform cortex), combined to show different sensory processing strategies for olfactory emotional cues in impulsive children. Finally, we hypothesize that the cerebellum plays a pivotal role in modulating decision-making for impulsive children.

rs3764435 Associated With Parkinson's Disease in Mexican Mestizos: Case-Control Study Reveals Protective Effects Against Disease Development and Cognitive Impairment

Parkinson's disease (PD) is the second most common movement disorder. Genetic risk factors provide information about the pathophysiology of PD that could potentially be used as biomarkers. The ALDH1A1 gene encodes for the aldehyde dehydrogenase enzyme, which is involved in the disposal of toxic metabolites of dopamine. Due to the cytotoxic nature of aldehydes, their detoxification is essential for cellular homeostasis. It has been reported that ALDH1A1 expression levels and activity are decreased in PD patients. A deficit in ALDH1A1 activity in the substantia nigra, may lead to the accumulation of neurotoxic aldehydes and eventually the cell death seen in PD. One of the single nucleotide polymorphisms (SNP) that may modulate ALDH1A1 activity levels is rs3764435 (A/C). To investigate whether a statistical association exists between PD and the SNP rs3764435, we carried out a population-based Case-Control association study (120 PD patients and 178 non-PD subjects) in Mexican mestizos. DNA was extracted from blood samples and genotyped for rs3764435 using real-time PCR. A significant difference was found between PD cases and controls in both allelic and genotypic frequencies. The calculated OR showed that the C/C genotype is a protective factor under the codominant and recessive models of inheritance. However, after stratifying by sex, the protective role of this genotype is conserved only in men. Also, under the codominant and dominant models, rs3764435 appears to exert a protective effect against cognitive impairment in PD patients. Here for the first time, we show an association between PD and rs3764435 in a Mexican mestizo population, suggesting it confers neuroprotection for dementia in PD and is neuroprotective against developing PD in the males of this population. While analysis of the SNP looks favorable, replication of our study in cell lines or rs3764435 KO mice is required to validate these results.

Continuous Theta Burst Stimulation Over the Right Orbitofrontal Cortex Impairs Conscious Olfactory Perception

The right orbitofrontal cortex (rOFC) has been proposed as the region where conscious olfactory perception arises; however, evidence supporting this hypothesis has all been collected from neuroimaging and lesion studies in which only correlation and not a temporal pattern can be established. Continuous theta burst stimulation (cTBS) causes a reversible disruption of cortical activity and has been used successfully to disrupt orbitofrontal activity. To overcome intrinsic limitations of current experimental research, a crossover, double-blind, prospective and longitudinal study was carried out in which cTBS was applied over the rOFC to evaluate its effect on odorant stimuli detection. All subjects received real and sham cTBS. Experimental procedures were done in two different sessions with a separation of at least one week between them to avoid carryover and learning effects. A total of 15 subjects completed the experiment, and their data were included in the final analysis (10 women, 5 men, mean age 22.40 ± 3.41). Every session consisted of two different measures of the conscious olfactory perception task: A baseline measure and one 5 min after cTBS/sham. Compared to baseline, marks in the olfactory task during the sham cTBS session increased (p = 0.010), while marks during the real cTBS session decreased (p = 0.017). Our results support the hypothesis that rOFC is an important node of a complex network required for conscious olfactory perception to arise. However, the exact mechanism that explains our results is unclear and could be explained by the disruption of other cognitive functions related to the rOFC.

Neurophysiological changes after cognitive-motor tasks in Parkinson's disease patients with deep brain stimulation

Chronic deep brain stimulation (CDBS) is a surgical treatment that reduces the cardinal signs of Parkinson's disease (PD). Although CDBS has been in use for a long time, very little has been reported on its supposed effects on cognition, particularly in relation to implants in the subthalamic nucleus. The results of the rare studies that do exist are controversial, and in many cases the studies have several design flaws. The present study compared cortical activation during three tasks (action execution, action observation and motor imagery) in PD patients with and without subthalamic implants. The study sample consisted of 36 volunteers, divided into three groups: healthy controls, PD patients with CDBS of the subthalamic nucleus, and PD patients without CDBS. Through a quantitative electroencephalogram assessment, absolute beta power was examined to observe the interaction between group and cognitive motor tasks. The electrodes at sites Fp1, Fp2, F7, F8, F3, Fz and F4, located in the prefrontal and frontal regions, were analyzed and a Group x Task interaction (p < 0.05) was observed for all of them. These findings suggest that CDBS of the subthalamic nucleus is efficient in reducing some of the effects of PD in these study tasks. At the same time, the dysfunctions found in several cortical areas, characteristic of PD, limited the effects of the CDBS. The results of this study suggest that CDBS of the subthalamic nucleus can modulate cognitive-motor aspects of PD.

Responses of Endothelial Cells Towards Ischemic Conditioning Following Acute Myocardial Infarction

One of the primary therapeutic goals of modern cardiology is to design strategies aimed at minimizing myocardial infarct size and optimizing cardiac function following acute myocardial infarction (AMI). Patients with AMI who underwent reperfusion therapy display dysfunction of the coronary endothelium. Consequently, ischemic endothelial cells become more permeable and weaken their natural anti-thrombotic and anti-inflammatory potential. Ischemia-reperfusion injury (IRI) is associated with activation of the humoral and cellular components of the hemostatic and innate immune system, and also with excessive production of reactive oxygen species (ROS), the inhibition of nitric oxide synthase, and with inflammatory processes. Given its essential role in the regulation of vascular homeostasis, involving platelets and leukocytes among others, dysfunctional endothelium can lead to increased risk of coronary vasospasm and thrombosis. Endothelial dysfunction can be prevented by ischemic conditioning with a protective intervention based on limited intermittent periods of ischemia and reperfusion. The molecular mechanisms and signal transduction pathways underlying conditioning phenomena in the coronary endothelium have been described as involving less ROS production, reduced adhesion of neutrophils to endothelial cells and diminished inflammatory reactions. This review summarizes our current understanding of the cellular and molecular mechanisms regulating IRI-affected and -damaged coronary endothelium, and how ischemic conditioning may preserve its function.

Frontotemporal Lobe Degeneration as Origin of Scans Without Evidence of Dopaminergic Deficit

The term scans without evidence of dopaminergic deficit (SWEDD) can be associated with any patient diagnosed at first with Parkinson's disease but with a negative dopamine transporter-single photon emission computed tomography (DaTSPECT), which does not confirm the presynaptic dopaminergic deficiency. Therefore, an alternative diagnosis should be sought to support parkinsonism as a clinical diagnosis. Parkinsonism is a well-known manifestation of frontotemporal lobar degeneration (FTLD), particularly frequent in those with positive DaTSPECT. Here, we reinforce previous observations that parkinsonism can be present in FTLD patients with negative DaTSPECT and therefore, FTLD may account for a percentage of patients with SWEDD. We gather the clinical observations supporting this hypothesis and describe a case report illustrating this idea. Studies suggest the result of DaTSPECT in FTLD may depend on the neuropathology and clinical subtype. However, most studies do not provide a clinical description of the clinical subtype or pathological features making the association between subtypes of FTLD and DaTSPECT results impossible at the moment. Further studies correlating clinical, neuropsychological, neuroimaging, genetic, and pathology findings are needed to better understand parkinsonism in FTLD.

Hypocholesterolemia is an independent risk factor for depression disorder and suicide attempt in Northern Mexican population

BACKGROUND

Cholesterol has been associated as a risk factor for cardiovascular disease. Recently, however, there is growing evidence about crucial requirement of neuron membrane cholesterol in the organization and function of the 5-HT_1A serotonin receptor. For this, low cholesterol level has been reported to be associated with depression and suicidality. However there have been inconsistent reports about this finding and the exact relationship between these factors remains controversial. Therefore, we investigated the link between serum cholesterol and its fractions with depression disorder and suicide attempt in 467 adult subjects in Mexican mestizo population.

METHODS

Plasma levels of total cholesterol, triglycerides, and high-density lipoprotein cholesterol (HDL-c) and low density lipoprotein cholesterol (LDL-c) were determined in 261 MDD patients meeting the DSM-5 criteria for major depressive disorder (MDD), 59 of whom had undergone an episode of suicide attempt, and 206 healthy controls.

RESULTS

A significant decrease in total cholesterol, LDL-cholesterol, VLDL-cholesterol and triglyceride serum levels was observed in the groups of MDD patients and suicide attempt compared to those without suicidal behavior (p < 0.05). After adjusting for covariates, lower cholesterol levels were significantly associated with MDD (OR 4.229 CI 95% 2.555 - 7.000, p<.001) and suicide attempt (OR 5.540 CI 95% 2.825 - 10.866, p<.001) CONCLUSIONS: These results support the hypothesis that lower levels of cholesterol are associated with mood disorders like MDD and suicidal behavior. More mechanistic studies are needed to further explain this association.

Neurobiology of Bipolar Disorder: Abnormalities on Cognitive and Cortical Functioning and Biomarker Levels

Bipolar disorder (BD) affects 1 to 1.5% of the world population and consists of at least one manic episode (or hypomanic) associated with depressive episodes, interspersed with periods of euthymic mood. Recurrent crises lead to significant disability in BD patients, and correlates negatively to social and occupational adjustment. Such disability can be explained by a series of events, such as cortical and altered metabolic activity, impairments in cognitive functions, and in core anatomical structures involved in mood modulation. Therefore, our review aims to provide information on the current research related to the pathophysiology of BD. We will review the cognitive and brain functioning, and biomarkers of BD. The current literature shows that cognitive deficits are commonly observed in all phases in BD patients, independent of a remissive state. These deficits are assigned to functional, structural and metabolic changes, particularly in the pre-frontal cortex region, hippocampus and amygdala, along with the connections between them, as well as decreased baseline brain-derived neurotrophic factor levels or imbalance between pro- and anti-inflammatory cytokines, implying a lower physical ability to reestablish from a stressful stimulus. BD patients effectively present a differentiated pattern of cortical, neuroanatomical and functional responses. It is suggested that physiological processes occur differently in bipolar subjects compared to healthy individuals, affecting behavior and brain function in such patients. Future directions are yet necessary to establish the best way to neutralize or reverse these events.

Nanomaterials for Neurology: State-of-the-Art

Despite the numerous challenges associated with the application of nanotechnology in neuroscience, it promises to have a significant impact on our understanding of how the nervous system works, how it fails in disease, and the development of earlier and less-invasive diagnostic procedures so we can intervene in the pre-clinical stage of neurological disease before extensive neurological damage has taken place. Ultimately, both the challenges and opportunities that nanotechnology presents stem from the fact that this technology provides a way to interact with neural cells at the molecular level. In this review we provide a neurobiological overview of key neurological disorders, describe the different types of nanomaterials in use and discuss their current and potential uses in neuroscience. We also discuss the issue of toxicity in these nanomaterials. This review presents many of the different applications that advances in nanotechnology are having in the field of neurological sciences, especially the high impact they are having in the development of new treatment modalities for neurological disorders that will induce the expected physiological response while minimizing undesirable secondary effects. In conclusion, we weigh in on what the promises and challenges are for future development in this groundbreaking field.

Psychiatric comorbidities in movement disorders

Psychiatric comorbidities are common in movement disorders. This review provides a practical approach to help clinicians to recognize psychiatric disorders in the most frequent movement disorders. However, the extent of neurodegeneration, as well as the impact of medications with considerable CNS effects, influences the diverse psychiatric presentations that, in turn, are influenced by the stress of living with a movement disorder. Depression, anxiety, and psychosis are the most common psychiatric comorbidities in movement disorders and of the medications used to treat the motor disturbances. These psychiatric problems impair patients' functioning throughout the course of the chronic neurodegenerative diseases. Due to the direct connection between brain dysfunction and psychiatric symptoms, there is hope that understanding the psychiatric comorbidities in movement disorders will lead to a better quality-of-life.

Therapeutic Interventions for Vascular Parkinsonism: A Systematic Review and Meta-analysis

Background

Vascular parkinsonism (VP) is defined as the presence of parkinsonian syndrome, evidence of cerebrovascular disease, and an established relationship between the two disorders. However, the diagnosis of VP is problematic, particularly for the clinician confronted with moving from diagnosis to treatment. Given the different criteria used in the diagnosis of VP, the effectiveness of available therapeutic interventions for this disease are currently unknown.

Methods

To assess the clinical response of all published therapeutic interventions for VP that have been reported in the literature, we conducted a systematic review looking for VP subjects treated with any therapeutic intervention. To clarify the prevalence of responsiveness to levodopa among VP subjects, we conducted a meta-analysis of 17 observational studies retrieved with the search criteria of our review. Also, four studies were included in a second analysis to explore if nigrostriatal lesion affected the prevalence of levodopa response in VP subjects. Relevant articles were identified from MEDLINE, Scopus, and Web of Science published until June 2017.

Results

436 non-duplicate citations were identified for screening, 107 articles were assessed for eligibility, and only 23 observational studies were included in this review. No randomized clinical trials were found. Four different therapies were found in the literature; among them, levodopa was the only one repetitively reported. The calculated event rate of levodopa response in VP subjects was of 0.304 [95% confidence interval (CI) of 0.230–0.388]. The overall odds ratio for good response to levodopa in VP with lesion in the nigrostriatal pathway vs. no lesion in the nigrostriatal pathway was 15.15 (95% CI: 5.2–44.17).

Conclusion

Despite the lack of randomized controlled trials, results of this systematic review and meta-analysis show that VP subjects, as operationally defined here, have a low response rate to levodopa; nigrostriatal lesion could be used as a proxy predictor of levodopa response in VP subjects. Other therapies seem to be co-adjuvant. Randomized controlled trials with a clear definition of VP are necessary to be able to assign positive or negative predictive values to available treatments and to recommend any of the therapeutic interventions for these subjects.

Implications of DNA Methylation in Parkinson's Disease

It has been 200 years since Parkinson’s disease (PD) was first described, yet many aspects of its etiopathogenesis remain unclear. PD is a progressive and complex neurodegenerative disorder caused by genetic and environmental factors including aging, nutrition, pesticides and exposure to heavy metals. DNA methylation may be altered in response to some of these factors; therefore, it is proposed that epigenetic mechanisms, particularly DNA methylation, can have a fundamental role in gene–environment interactions that are related with PD. Epigenetic changes in PD-associated genes are now widely studied in different populations, to discover the mechanisms that contribute to disease development and identify novel biomarkers for early diagnosis and future pharmacological treatment. While initial studies sought to find associations between promoter DNA methylation and the regulation of associated genes in PD brain tissue, more recent studies have described concordant DNA methylation patterns between blood and brain tissue DNA. These data justify the use of peripheral blood samples instead of brain tissue for epigenetic studies. Here, we summarize the current data about DNA methylation changes in PD and discuss the potential of DNA methylation as a potential biomarker for PD. Additionally, we discuss environmental and nutritional factors that have been implicated in DNA methylation. Although the search for significant DNA methylation changes and gene expression analyses of PD-associated genes have yielded inconsistent and contradictory results, epigenetic modifications remain under investigation for their potential to reveal the link between environmental risk factors and the development of PD.

Role of N-Arachidonoyl-Serotonin (AA-5-HT) in Sleep-Wake Cycle Architecture, Sleep Homeostasis, and Neurotransmitters Regulation

The endocannabinoid system comprises several molecular entities such as endogenous ligands [anandamide (AEA) and 2-arachidonoylglycerol (2-AG)], receptors (CB₁ and CB₂), enzymes such as [fatty acid amide hydrolase (FAHH) and monoacylglycerol lipase (MAGL)], as well as the anandamide membrane transporter. Although the role of this complex neurobiological system in the sleep–wake cycle modulation has been studied, the contribution of the blocker of FAAH/transient receptor potential cation channel subfamily V member 1 (TRPV1), N-arachidonoyl-serotonin (AA-5-HT) in sleep has not been investigated. Thus, in the present study, varying doses of AA-5-HT (5, 10, or 20 mg/Kg, i.p.) injected at the beginning of the lights-on period of rats, caused no statistical changes in sleep patterns. However, similar pharmacological treatment given to animals at the beginning of the dark period decreased wakefulness (W) and increased slow wave sleep (SWS) as well as rapid eye movement sleep (REMS). Power spectra analysis of states of vigilance showed that injection of AA-5-HT during the lights-off period diminished alpha spectrum across alertness in a dose-dependent fashion. In opposition, delta power spectra was enhanced as well as theta spectrum, during SWS and REMS, respectively. Moreover, the highest dose of AA-5-HT decreased wake-related contents of neurotransmitters such as dopamine (DA), norepinephrine (NE), epinephrine (EP), serotonin (5-HT) whereas the levels of adenosine (AD) were enhanced. In addition, the sleep-inducing properties of AA-5-HT were confirmed since this compound blocked the increase in W caused by stimulants such as cannabidiol (CBD) or modafinil (MOD) during the lights-on period. Additionally, administration of AA-5-HT also prevented the enhancement in contents of DA, NE, EP, 5-HT and AD after CBD of MOD injection. Lastly, the role of AA-5-HT in sleep homeostasis was tested in animals that received either CBD or MOD after total sleep deprivation (TSD). The injection of CBD or MOD increased alertness during sleep rebound period after TSD. However, AA-5-HT blocked this effect by allowing animals to display an enhancement in sleep across sleep rebound period. Overall, our findings provide evidence that AA-5-HT is an important modulator of sleep, sleep homeostasis and neurotransmitter contents.

Auditory- and Vestibular-Evoked Potentials Correlate with Motor and Non-Motor Features of Parkinson's Disease

Degeneration of several brainstem nuclei has been long related to motor and non-motor symptoms (NMSs) of Parkinson's disease (PD). Nevertheless, due to technical issues, there are only a few studies that correlate that association. Brainstem auditory-evoked potential (BAEP) and vestibular-evoked myogenic potential (VEMP) responses represent a valuable tool for brainstem assessment. Here, we investigated the abnormalities of BAEPs, ocular VEMPs (oVEMPs), and cervical VEMPs (cVEMPs) in patients with PD and its correlation to the motor and NMSs. Fifteen patients diagnosed as idiopathic PD were evaluated by Unified Parkinson's Disease Rating Scale and its subscores, Hoehn and Yahr scale, Schwab and England scale, and Non-Motor Symptoms Scale. PD patients underwent pure-tone, speech audiometry, tympanometry, BAEP, oVEMPs, and cVEMPs, and compared to 15 age-matched control subjects. PD subjects showed abnormal BAEP wave morphology, prolonged absolute latencies of wave V and I-V interpeak latencies. Absent responses were the marked abnormality seen in oVEMP. Prolonged latencies with reduced amplitudes were seen in cVEMP responses. Rigidity and bradykinesia were correlated to the BAEP and cVEMP responses contralateral to the clinically more affected side. Contralateral and ipsilateral cVEMPs were significantly correlated to sleep (p = 0.03 and 0.001), perception (p = 0.03), memory/cognition (p = 0.025), and urinary scores (p = 0.03). The oVEMP responses showed significant correlations to cardiovascular (p = 0.01) and sexual dysfunctions (p = 0.013). PD is associated with BAEP and VEMP abnormalities that are correlated to the motor and some non-motor clinical characteristics. These abnormalities could be considered as potential electrophysiological biomarkers for brainstem dysfunction and its associated motor and non-motor features.

Relationship Among Body Image, Anthropometric Parameters and Mental Health in Physical Education Students

Background

The prevalence of body image dissatisfaction (BID) is currently high. Given that psychological well-being is associated with the body measurements imposed by esthetic standards, BID is an important risk factor for mental disorders.

Objective

Identify the prevalence of BID, and compare anthropometric and mental health parameters between individuals satisfied and dissatisfied with their body image.

Method

A total of 140 university students completed the silhouette scale to screen for BID. Anthropometric measures, body mass index (BMI), waist circumference (WC) and body fat percentage (BFP) were used. To investigate mental health, The State-Trait Anxiety Inventories (STAI-S and STAI-T), Profile of Mood States (POMS) scale and Quality of Life (QOL-36) questionnaire were used to investigate mental health. The Student’s t-test was applied to compare anthropometric and mental health parameters.

Results

67.1% of university students exhibited BID. There was a significant difference (p = 0.041) in BF and WC (p = 0.048) between dissatisfied and satisfied individuals. With respect to mood states, significant differences were observed for anger (p = 0.014), depression (p = 0.011), hostility (p = 0.006), fatigue (p = 0.013), mental confusion (p = 0.021) and total mood disturbance (TMD) (p = 0.001). The mental aspect of QOL was significantly higher (p = 0.001) in satisfied university students compared to their dissatisfied counterparts.

Conclusion

BID was high and it seems to be influenced by anthropometric measures related to the amount and distribution of body fat. This dissatisfaction may have a negative effect on the quality of life and mood state of young adults.

Toxoplasma gondii exposure and Parkinson's disease: a case-control study

OBJECTIVES

To determine the association between Toxoplasma gondii infection and Parkinson's disease and to investigate whether T. gondii seropositivity is associated with the general characteristics of patients with Parkinson's disease.

DESIGN

Case-control study.

SETTING

Cases and controls were enrolled in Durango City, Mexico.

PARTICIPANTS

65 patients with Parkinson's disease and 195 age- and gender-matched control subjects without Parkinson's disease.

PRIMARY AND SECONDARY OUTCOME MEASURES

Serum samples of participants were analysed for anti-T. gondii IgG and IgM antibodies by commercially available enzyme-linked immunoassays. Prevalence of T. gondii DNA was determined in seropositive subjects using PCR. The association between clinical data and infection was examined by bivariate analysis.

RESULTS

Anti-T. gondii IgG antibodies were found in 6/65 cases (9.2%) and in 21/195 controls (10.8%) (OR 0.84; 95% CI 0.32 to 2.18; p=0.81). The frequency of high (>150 IU/mL) antibody levels was similar among cases and controls (p=0.34). None of the anti-T. gondii IgG positive cases and four of the anti-T. gondii IgG positive controls had anti-T. gondii IgM antibodies (p=0.54). The prevalence of T. gondii DNA was comparable in seropositive cases and controls (16.7% and 25%, respectively; p=1.0). Seroprevalence of T. gondii infection was associated with a young age onset of disease (p=0.03), high Unified Parkinson Disease Rating Scale scores (p=0.04) and depression (p=0.02). Seropositivity to T. gondii infection was lower in patients treated with pramipexole than in patients without this treatment (p=0.01). However, none of the associations remained significant after Bonferroni correction.

CONCLUSIONS

The results do not support an association between T. gondii infection and Parkinson's disease. However, T. gondii infection might have an influence on certain symptoms of Parkinson's disease. Further research to elucidate the role of T. gondii exposure on Parkinson's disease is warranted.

Can Transcranial Direct Current Stimulation Improve the Resistance Strength and Decrease the Rating Perceived Scale in Recreational Weight-Training Experience?

Lattari, E, Andrade, ML, Filho, AS, Moura, AM, Neto, GM, Silva, JG, Rocha, NB, Yuan, T-F, Arias-Carrión, O, and Machado, S. Can transcranial direct current stimulation improve the resistance strength and decrease the rating perceived scale in recreational weight-training experience? J Strength Cond Res 30(12): 3381-3387, 2016-The goal of this study was to evaluate the acute efficacy of anodic transcranial direct current stimulation on the total volume of repetitions and perceived exertion in recreationally trained individuals in strength. The sample consisted of 10 participants trained in exercise against resistance for at least 3 months. Participants underwent elbow flexion exercise at barbell with a specific load of 10 repetition maximum (10RM), responded immediately after the OMNI-RES scale, and were stimulated for 20 minutes with a tDSC protocol (2 mA), depending on randomization. After applying the tDSC, subjects were again subjected to perform elbow flexion with 10RM load and, soon after, again responded to OMNI-RES scale. All subjects underwent the 3 experimental conditions of the study, c-tDSC, a-tDSC, and sham-tDSC, which were randomized. A range of 48-72 hours was allowed between each assessment visit. An interaction to condition and time (F = 52.395; p ≤ 0.001) has shown that repetitions completed after anodic condition were higher compared with the other conditions in the postsession. In relation to perceived exertion, verified by OMNI-RES scale, 2-way analysis of variance for repeated measures showed an interaction between condition and time (F = 28.445; p ≤ 0.001), where the perceived exertion was decreased after the a-tDSC condition and increased after the c-tDSC condition. In strict terms of performance, it seems to be beneficial to attend a session of 20 minutes a-tDSC, when strength training practitioners can no longer support high-volume training and have increased responses in the perceived exertion.

Acute Affective Responses and Frontal Electroencephalographic Asymmetry to Prescribed and Self-selected Exercise

Objective:

Our goal was to compare affective responses and frontal electroencephalographic alpha asymmetry induced by prescribed exercise (PE) and self-selected exercise (SS).

Method:

Twenty active participants underwent a submaximal exercise test to estimate maximal oxygen consumption (VO_2max). Participants enrolled a cross-over randomized study where each participant completed three conditions: PE (50%PVO_2max), SS and Control. The electroencephalography was performed before and after exercise. The feeling scale, felt arousal scale and heart rate were recorded before, during and after each condition. The ratings of perceived exertion were recorded during and after each condition.

Results:

The heart rate and ratings of perceived exertion showed higher values in the PE and SS conditions compared to controls, with no differences between the PE and SS conditions. For the feeling scale, the SS presented higher values compared to the PE and Control conditions. The felt arousal scale presented higher values in the PE and SS conditions compared to control. There was no interaction between condition and moment, or main effect for condition and moment for frontal alpha asymmetry (InF4-InF3).

Conclusion:

The SS provided better affective responses compared to PE, thus can consider self-selected intensity as an appropriate option. In general, no frontal alpha asymmetry was seen due to an exercise intervention.

Vagus nerve stimulation in treating depression: A tale of two stories

Vagus nerve stimulation (VNS) has been widely used to treat different neurological disorders, especially epilepsy. Accumulating evidence also suggests its potential application in antidepressive therapy, given that VNS has been confirmed by several clinical trials to exert long-term effects on mitigating depression and reducing the risk of relapse in depressed patients. Likewise, VNS has also proven to ameliorate the behavioral deficits in a rat model of depression. While the influences of VNS on monoamine metabolism and mood improvement are well-recognized, the underlying mechanisms mediating its antidepressive action remain poorly understood. Recent findings suggest that VNS-enhanced proliferation of hippocampal neural progenitor cells (NPCs) and synaptic transmission might serve as a monoamine-independent pathway contributive to the beneficial effects of VNS on depression. Here we briefly reviewed the recent progress in this field, based on which we propose that there might be, at least, two little-overlapped, and yet interactive pathways mediating the antidepressive action of VNS.

Neural Mechanisms of Exercise: Effects on Gut Miccrobiota and Depression

Microbiota is a set of microorganisms resident in gut ecosystem that reacts to psychological stressful stimuli, and is involved in depressed or anxious status in both animals and human being. Interestingly, a series of studies have shown the effects of physical exercise on gut microbiota dynamics, suggesting that gut microbiota regulation might act as one mediator for the effects of exercise on the brain. Recent studies found that gut microbiota dynamics are also regulated by metabolism changes, such as through physical exercise or diet change. Interestingly, physical exercise modulates different population of gut bacteria in compared to food restriction or rich diet, and alleviates gut syndromes to toxin intake. Gut microbiota could as well contribute to the beneficial effects of exercise on cognition and emotion, either directly through serotonin signaling or indirectly by modulating metabolism and exercise performance.

Neuroscience of Exercise: Association Among Neurobiological Mechanisms and Mental Health

Neuroscience is an emergent research field that comprises many multidisciplinary investigations, searches for explanations about the relationship between the body and the brain. Here, we will give a little summary of this field showing the main current findings. We discuss the lack of consistent data about the relationship among exercise for neurodegenerative diseases and psychiatric disorders, sports performance and rehabilitation, and therefore, the difficult to describe cause-effect associations or to describe in detail the neurobiological mechanisms underlying these associations.

From Mind to Body: Is Mental Practice Effective on Strength Gains? A Meta-Analysis

Mental practice is an internal reproduction of a motor act (whose intention is to promote learning and improving motor skills). Some studies have shown that other cognitive strategies also increase the strength and muscular resistance in healthy people by the enhancement of the performance during dynamic tasks. Mental training sessions may be primordial to improving muscle strength in different subjects. The aim of this study was to systematically review and meta-analiyze studies that assessed whether mental practice is effective in improving muscular strength. We conducted an electronic-computed search in Pub-Med/Medline and ISI Web of Knowledge, Scielo and manual searchs, searching papers written in English between 1991 and 2014. There were 44 studies in Pub-Med/Medline, 631 in ISI Web of Knowledge, 11 in Scielo and 3 in manual searchs databases. After exclusion of studies for duplicate, unrelated to the topic by title and summary, different samples and methodologies, a meta-analysis of 4 studies was carried out to identify the dose-response relationship. We did not find evidence that mental practice is effective in increasing strength in healthy individuals. There is no evidence that mental practice alone can be effective to induce strength gains or to optimize the training effects.

Comparison Among Aerobic Exercise and Other Types of Interventions to Treat Depression: A Systematic Review

Depression is a common and disabling disease that affects over 100 million people worldwide and can have a significant impact on physical and mental health, reducing their quality of life. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of chronic aerobic exercise compared with other types of interventions to treat depression, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. In this review, the data analyzed allows us to claim that alternative therapies, such as exercise, are effective on controlling and reducing symptoms. 69.3% of the studies that investigated the antidepressant effects of exercise on depressive were significant, and the other 30.7% of the studies improved only in general physiological aspects, such as increased oxygen uptake, increased use of blood glucose and decreased body fat percentage, with no improvement on symptoms of depression. From the sample analyzed, 71.4% was composed of women, and regarding the severity of symptoms, 85% had mild to moderate depression and only 15% had moderate to severe depression. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressants in symptomatology and cognitive function in depression, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.

Effects of Aerobic Exercise on Anxiety Disorders: A Systematic Review

Anxiety disorders are the most common psychiatric disorders observed currently. It is a normal adaptive response to stress that allows coping with adverse situations. Nevertheless, when anxiety becomes excessive or disproportional in relation to the situation that evokes it or when there is not any special object directed at it, such as an irrational dread of routine stimuli, it becomes a disabling disorder and is considered to be pathological. The traditional treatment used is medication and cognitive behavioral psychotherapy, however, last years the practice of physical exercise, specifically aerobic exercise, has been investigated as a new non-pharmacological therapy for anxiety disorders. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of aerobic exercise compared with other types of interventions to treat anxiety, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. The sample analyzed, 66.8% was composed of women and 80% with severity of symptoms anxiety as moderate to severe. The data analyzed in this review allows us to claim that alternative therapies like exercise are effective in controlling and reducing symptoms, as 91% of anxiety disorders surveys have shown effective results in treating. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressant symptoms and cognitive function in anxiety, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.

Structural Neuroimaging of the Medial Temporal Lobe in Alzheimer's Disease Clinical Trials

Atrophy in the medial temporal lobe (MTA) is being used as a criterion to support a diagnosis of Alzheimer's disease (AD). There are several structural neuroimaging approaches for quantifying MTA, including semiquantitative visual rating scales, volumetry (3D), planimetry (2D), and linear measures (1D). Current applications of structural neuroimaging in Alzheimer's disease clinical trials (ADCTs) incorporate it as a tool for improving the selection of subjects for enrollment or for stratification, for tracking disease progression, or providing evidence of target engagement for new therapeutic agents. It may also be used as a surrogate marker, providing evidence of disease-modifying effects. However, despite the widespread use of volumetric magnetic resonance imaging (MRI) in ADCTs, there are some important challenges and limitations, such as difficulties in the interpretation of results, limitations in translating results into clinical practice, and reproducibility issues, among others. Solutions to these issues may arise from other methodologies that are able to link the results of volumetric MRI from trials with conventional MRIs performed in routine clinical practice (linear or planimetric methods). Also of potential benefit are automated volumetry, using indices for comparing the relative rate of atrophy of different regions instead of absolute rates of atrophy, and combining structural neuroimaging with other biomarkers. In this review, authors present the existing structural neuroimaging approaches for MTA quantification. They then discuss solutions to the limitations of the different techniques as well as the current challenges of the field. Finally, they discuss how the current advances in AD neuroimaging can help AD diagnosis.

Oxidative Stress and Adult Neurogenesis

There is a growing evidence that adult neurogenesis is critical for brain function. The reactive oxygen species (ROS) is accumulated during adult neurogenesis as a physiological mechanism; while ROS overload impairs adult neurogenesis during ageing, neuroinflammation and neurodegeneration. Here we propose that targeting oxidative stress provides a novel way to regulate adult neurogenesis and manage different brain diseases.

Characterization of Mitogen-Activated Protein Kinase Expression in Nucleus Accumbens and Hippocampus of Rats Subjected to Food Selection in the Cafeteria Diet Protocol

Obesity is a world-wide health problem that requires different experimental perspectives to understand the onset of this disease, including the neurobiological basis of food selection. From a molecular perspective, obesity has been related with activity of several endogenous molecules, including the mitogenactivated protein kinases (MAP-K). The aim of this study was to characterize MAP-K expression in hedonic and learning and memory brain-associated areas such as nucleus accumbens (AcbC) and hippocampus (HIPP) after food selection. We show that animals fed with cafeteria diet during 14 days displayed an increase in p38 MAP-K activity in AcbC if chose cheese. Conversely, a diminution was observed in animals that preferred chocolate in AcbC. Also, a decrease of p38 MAP-K phosphorylation was found in HIPP in rats that selected either cheese or chocolate. Our data demonstrate a putative role of MAP-K expression in food selection. These findings advance our understanding of neuromolecular basis engaged in obesity.

Mental Practice Combined with Motor Rehabilitation to Treat Upper Limb Hemiparesis of Post-Stroke Patients: Clinical and Experimental Evidence

Stroke is one of the major causes of disability in the world. Due to the extended lifetime of the world's population, the number of people affected by stroke has increased substantially over the last years. Stroke may lead to sensorimotor deficits, usually causing hemiplegia or hemiparesia. In order to reduce motor deficits and accelerate functional recovery, MP combined with motor rehabilitation was introduced to the rehabilitation process of post-stroke patients. Evidence has shown that MP combining with motor rehabilitation based on activities of daily living was more effective than conventional motor rehabilitation used per se. This combination proved very useful and effective, with significant results in improvement of motor deficits in post-stroke patients. However, further studies must be conducted to determine specific parameters, such as type of imagery, frequency or duration.

Treatment of Cognitive Deficits in Alzheimer's disease: A psychopharmacological review

The growing and aging population has contributed to the increased prevalence of Alzheimer's disease (AD) and other types of dementia in the world. AD is a progressive and degenerative brain disease with an onset characterized by episodic memory impairments, although progressive deficits can be observed in several domains including language, executive functions, attention and working memory. The relationship between cognitive impairments and the topography and progression of brain neuropathology is well established. The pathophysiologic mechanisms and processes that underline the course of cognitive and clinical decline have been the theoretical support for the development of pharmacological treatments for AD. Cholinesterase inhibitors (ChEIs) and N-methyl-D-aspartate (NMDA) antagonists are the main drugs used in the management of global cognitive impairment and several studies also explore the effects of both in specific cognitive measures. Recent research trends also examine the effects of combination therapy using both compounds. This review aims to update practical recommendations for the treatment of global cognitive functioning and specific neurocognitive deficits in AD using ChEIs, NMDA antagonists and combination therapy with both drugs.

Is mental practice an effective adjunct therapeutic strategy for upper limb motor restoration after stroke? A systematic review and meta- analysis

Stroke is one of the most common conditions requiring rehabilitation, and its motor impairments are a major cause of permanent disability. Hemiparesis is observed by 80% of the patients after acute stroke. Neuroimaging studies showed that real and imagined movements have similarities regarding brain activation, supplying evidence that those similarities are based on the same process. Within this context, the combination of mental practice (MP) with physical and occupational therapy appears to be a natural complement based on neurorehabilitation concepts. Our study seeks to investigate if MP for stroke rehabilitation of upper limbs is an effective adjunct therapy. PubMed (Medline), ISI knowledge (Institute for Scientific Information) and SciELO (Scientific Electronic Library) were terminated on 20 February 2015. Data were collected on variables as follows: sample size, type of supervision, configuration of mental practice, setting the physical practice (intensity, number of sets and repetitions, duration of contractions, rest interval between sets, weekly and total duration), measures of sensorimotor deficits used in the main studies and significant results. Random effects models were used that take into account the variance within and between studies. Seven articles were selected. As there was no statistically significant difference between the two groups (MP vs control), showed a - 0.6 (95% CI: -1.27 to 0.04), for upper limb motor restoration after stroke. The present meta-analysis concluded that MP is not effective as adjunct therapeutic strategy for upper limb motor restoration after stroke.

Lower uric Acid linked with cognitive dysfunction in the elderly

Uric acid has been associated as a risk factor for cardiovascular disease. Recently, however, there is growing evidence that uric acid plays a role as antioxidant in the brain. In cognitive dysfunction, vascular and oxidative stress mechanisms play a role, but the link remains unknown. Therefore, we investigated the link between serum uric acid-levels and cognitive function in 62 elderly subjects. The statistical analysis was adjusted to age, sex and cardiovascular risk factors. Here, we found that lower serum uric acid levels are linked to cognitive dysfunction. In a Mexican population, higher levels of uric acid are associated with a decreased risk of dementia.

Commentary: the effects of psychological stress on microglial cells in the brain

Psychological stress leads to activation and proliferation of microglial cells in different brain regions. These effects are mediated by inflammatory cytokines, as well as stress hormones including glucocorticoids and norepinephrine. Eliminating microglia from the nervous system or blocking their activation prevented the stress-induced impairments on brain cognitive functions. We conclude that microglial cells are important meditators underlying anti-depression therapies.

Repetitive transcranial magnetic stimulation to treat substance use disorders and compulsive behavior

Compulsions, like pathological gambling, binge-eating disorder, alcohol, tobacco or cocaine abuse and compulsive shopping have similar neurophysiological processing. This study aimed to examine the efficacy of repetitive transcranial magnetic stimulation (rTMS) in improving patient control over compulsive behavior. The rTMS modulatory role in cortical mesolimbic pathways possibly implies improvement of the inhibitory control system and compulsive consumption drive. Thus, craving reduction would be a component for control achievement. Within this context, 17 studies were found. Most studies applied rTMS over the left dorsolateral prefrontal cortex. Craving reduction was observed in 10 studies and was associated with improved control of compulsion in two of them. In one study reduction in consumption was found without reduction in craving. In addition, improvement in decision making was found in one study.