Decreased event-related theta power and phase-synchrony in young binge drinkers during target detection: An anatomically-constrained MEG approach.

BACKGROUND: The prevalence of binge drinking has risen in recent years. It is associated with a range of neurocognitive deficits among adolescents and young emerging adults who are especially vulnerable to alcohol use. Attention is an essential dimension of executive functioning and attentional disturbances may be associated with hazardous drinking. The aim of the study was to examine the oscillatory neural dynamics of attentional control during visual target detection in emerging young adults as a function of binge drinking. METHOD: In total, 51 first-year university students (18 ± 0.6 years) were assigned to light drinking ( n = 26), and binge drinking ( n = 25) groups based on their alcohol consumption patterns. A high-density magnetoencephalography signal was combined with structural magnetic resonance imaging in an anatomically constrained magnetoencephalography model to estimate event-related source power in a theta (4-7 Hz) frequency band. Phase-locked co-oscillations were further estimated between the principally activated regions during task performance. RESULTS: Overall, the greatest event-related theta power was elicited by targets in the right inferior frontal cortex and it correlated with performance accuracy and selective attention scores. Binge drinkers exhibited lower theta power and dysregulated oscillatory synchrony to targets in the right inferior frontal cortex, which correlated with higher levels of alcohol consumption. CONCLUSIONS: These results confirm that a highly interactive network in the right inferior frontal cortex subserves attentional control, revealing the importance of theta oscillations and neural synchrony for attentional capture and contextual maintenance. Attenuation of theta power and synchronous interactions in binge drinkers may indicate early stages of suboptimal integrative processing in young, highly functioning binge drinkers.

Functional and structural brain connectivity of young binge drinkers: a follow-up study.

Adolescence is a period of ongoing brain maturation characterized by hierarchical changes in the functional and structural networks. For this reason, the young brain is particularly vulnerable to the toxic effects of alcohol. Nowadays, binge drinking is a pattern of alcohol consumption increasingly prevalent among adolescents. The aim of the present study is to evaluate the evolution of the functional and anatomical connectivity of the Default Mode Network (DMN) in young binge drinkers along two years. Magnetoencephalography signal during eyes closed resting state as well as Diffusion Tensor Imaging (DTI) were acquired twice within a 2-year interval from 39 undergraduate students (22 controls, 17 binge drinkers) with neither personal nor family history of alcoholism. The group comparison showed that, after maintaining a binge drinking pattern along at least two years, binge drinkers displayed an increased brain connectivity of the DMN in comparison with the control group. On the other hand, the structural connectivity did not show significant differences neither between groups nor over the time. These findings point out that a continued pattern of binge drinking leads to functional alterations in the normal brain maturation process, even before anatomical changes can be detected.

Exploratory Analysis of Power Spectrum and Functional Connectivity During Resting State in Young Binge Drinkers: A MEG Study.

Binge Drinking (BD) is a pattern of intermittent intensive alcohol intake which has spread among young adults over the last decades. Adolescence constitutes a critical neuromaturation period in which the brain is particularly sensitive to the effects of alcohol. However, little is known about how BD affects the brain activity. This study aimed to characterize the brain's functional organization in BD and non-BD young population by means of analyzing functional connectivity (FC) and relative power spectra (PS) profiles measured with magnetoencephalography (MEG) during eyes-closed resting state. Our sample composed 73 first-year university students (35 BDs and 38 controls). Results showed that the BD subjects displayed a decreased alpha FC in frontal-parietal regions, and conversely, an enhanced FC in the delta, theta and beta bands in fronto-temporal networks. Besides the FC differences, the BD group showed a decreased PS within alpha range and an increased PS within theta range in the brain's occipital region. These differences in FC and PS measurements provide new evidence of the neurophysiological alterations related to the alcohol neurotoxicity and could represent an initial sign of an anomalous neural activity caused by a BD pattern of alcohol consumption during youth.

Evaluation of two experimental models of hepatic encephalopathy in rats.

The serious neuropsychological repercussions of hepatic encephalopathy have led to the creation of several experimental models in order to better understand the pathogenesis of the disease. In the present investigation, two possible causes of hepatic encephalopathy, cholestasis and portal hypertension, were chosen to study the behavioral impairments caused by the disease using an object recognition task. This working memory test is based on a paradigm of spontaneous delayed non-matching to sample and was performed 60 days after surgery. Male Wistar rats (225-250 g) were divided into three groups: two experimental groups, microsurgical cholestasis (N = 20) and extrahepatic portal hypertension (N = 20), and a control group (N = 20). A mild alteration of the recognition memory occurred in rats with cholestasis compared to control rats and portal hypertensive rats. The latter group showed the poorest performance on the basis of the behavioral indexes tested. In particular, only the control group spent significantly more time exploring novel objects compared to familiar ones (P < 0.001). In addition, the portal hypertension group spent the shortest time exploring both the novel and familiar objects (P < 0.001). These results suggest that the existence of portosystemic collateral circulation per se may be responsible for subclinical encephalopathy.

Evaluation of two experimental models of hepatic encephalopathy in rats

The serious neuropsychological repercussions of hepatic encephalopathy have led to the creation of several experimental models in order to better understand the pathogenesis of the disease. In the present investigation, two possible causes of hepatic encephalopathy, cholestasis and portal hypertension, were chosen to study the behavioral impairments caused by the disease using an object recognition task. This working memory test is based on a paradigm of spontaneous delayed non-matching to sample and was performed 60 days after surgery. Male Wistar rats (225-250 g) were divided into three groups: two experimental groups, microsurgical cholestasis (N = 20) and extrahepatic portal hypertension (N = 20), and a control group (N = 20). A mild alteration of the recognition memory occurred in rats with cholestasis compared to control rats and portal hypertensive rats. The latter group showed the poorest performance on the basis of the behavioral indexes tested. In particular, only the control group spent significantly more time exploring novel objects compared to familiar ones (P < 0.001). In addition, the portal hypertension group spent the shortest time exploring both the novel and familiar objects (P < 0.001). These results suggest that the existence of portosystemic collateral circulation per se may be responsible for subclinical encephalopathy.

Hippocampal AgNOR activity after chronic alcohol consumption and alcohol deprivation in rats.

Chronic alcohol consumption induces morphological changes in the central nervous system and withdrawal does not reverse these changes. It is well known that the hippocampal formation is one of the brain regions most sensitive to prolonged alcohol ingestion. The aim of our study was to evaluate the transcriptional neuronal activity by measuring the argyrophilic nucleolar organizer regions (AgNORs) in the dentate gyrus, CA3, and CA1 hippocampal areas from adult male rats receiving chronic administration of ethanol (ALC) and after withdrawal (WDL). The parameters evaluated were the number and area of AgNORs, together with the area of nucleus and the proportion between AgNOR and nuclear areas (ratio). The animals from ALC and WDL groups showed a reduction in the number of AgNOR per cell as compared to the control group. CA3 was the hippocampal area most affected by chronic alcohol intake. No improvement was observed in animals after withdrawal. Our data support the idea that the chronic intake of alcohol decreases protein synthesis in hippocampal neurons at an early age. This decrease may explain the memory impairment showed by rats receiving chronic treatment with alcohol because, both in humans and rats, it is associated with a reduction in the number of cholinergic neurons in the basal forebrain that would in turn affect the hippocampal function.

[An adrenaline-induced vasospasm as the form of presentation of variant angina]. / Vasoespasmo inducido por adrenalina como forma de presentación de una angina variante.

A 41-year-old-man without previous ischemic heart disease, developed a severe anaphylactic reaction. After administration of epinephrine (0.5 mg) the patient complained of chest pain. The electrocardiogram showed an elevation of ST segment in inferior leads. Myocardial necrosis was ruled out. Coronary arteriography disclosed normal coronary arteries. Eight months later, the patient developed severe chest pain during physical activity. ST elevation was again seen in inferior leads. ECG changes disappeared, when sublingual nitroglycerin was administered. A diagnosis of vasospastic angina was made. Exercise test was negative, during treatment with calcium-blocking agents. The patient subsequently remain free of symptoms taking medication. The physiological mechanisms of vasospastic angina and precipitating factors are discussed.

Sex-related differences in spatial learning during the early postnatal development of the rat.

Some authors have reported that male rats younger than 21 days old are unable to perform spatial learning correctly because they have still not developed the ability to use extra-maze cues. In experiment 1, we analyzed spatial learning in 14-, 21-, 30- and 42-day-old rats using the Morris water maze (MWM). According to our results, a good performance was observed in 30-day-old male rats whereas this was not observed in female rats until they were 42 days old. In experiment 2 we studied the role of sex hormones in this kind of learning using the MWM and 30-day-old rats (castrated male rats and female rats treated with testosterone propionate (TP) after birth). The latter group, the male control group and the castrated males all solved the task correctly. The objective of experiment 3 was to determine possible differences between the sexes in the use of taxon strategies in the T water maze. To summarize, sexual dimorphism was only observed in spatial learning during development.

[Hepatic alterations in a model of alcoholism in the rat]. / Alteraciones hepáticas en un modelo de alcoholismo en ratas.

Today, there are a great number of investigations about alcoholism. The effects of alcohol had been studied in Medicine, Psychology, Biology, Biochemistry, Physiology or Pharmacology. Many investigations are carried out with humans, however, in most experiments is necessary to use animal models. Many experimental models of alcoholism in animals are usually used in the laboratories and they present several differences among them. In our investigation we have studied the hepatic alterations in an experimental model of alcoholism in the rat because the liver is a very sensitive organ which suffers the effects of alcohol and its metabolites. We try to demonstrate that there are hepatic lesions which allows the use of this experimental in the study of the behavioral and neural parameters in the rat. The experimental model of alcoholism that we propose has been considered appropriate to study the behavioral effects of alcohol, not only because the animals show the characteristic hepatic lesions, but also because they do not suffer manipulations that could alter them and as a consequence bias the behavioral data.

NOR activity in hippocampal areas during the postnatal development and ageing.

The silver staining of the nucleolar organizer regions (Ag-NORs) was used in order to estimate the biosynthetic activity of three hippocampal areas (dentate gyrus, CA1 and CA3) during postnatal development and ageing. 32 Wistar rats were used and 4 groups were formed according to the age of the animals (14, 21, 90 days and 23 months). Several Ag-NOR parameters such as mean Ag-NOR area and the ratio between Ag-NOR and nuclear areas per neuronal cell were quantified using an image analysis system. High values of these parameters are associated with a high rate of rRNA transcription. In this way, the neural biosynthetic activity in all regions studied decreased as the older ages are reached. Differences between areas are shown with the dentate gyrus and CA1 areas decreasing faster. The different activity among these areas is discussed, taking into account the particular affect on these areas of some injuries and the ageing process. Our results support the hypothesis of NOR loss as a main cause of ageing as reported by other authors.

Glial and neuronal cell numbers and cytochrome oxidase activity in CA1 and CA3 during postnatal development and aging of the rat.

Stereological methods (neuron and glial cell numbers) and histochemical methods (cytochrome c oxidase) were used to study postnatal development and aging of the CA1 and CA3 hippocampal areas in male rats. No changes were observed in 10 microns sections in the neuronal population of areas CA1 and CA3 in any of the groups (14 days, 21 days, adult-90 days and elderly-22 months). Statistical differences were found in the number of glial cells in both the CA1 and CA3 areas. An increase was observed in cytochrome oxidase (CO) activity in the CA1 area in the 14 day old rats compared to the other groups while in area CA3 this parameter increased in the 14 and 21 day old groups and the group of adult rats. No significant changes in CO activity were found in the elderly rats in both areas. These results are discussed in the light of those recorded in other areas of the limbic system.

[Arterial hypertension unit in the health area]. / La consulta de hipertensión arterial en el área sanitaria.

For several decades the study of hypertension has been the subject of special attention in the arterial hypertension units and there has been a continuous search for different organizational models in order to improve diagnostic and therapeutic efficiency. The duty assigned to the cardiologist in each health area, according to the new model regulated by the Spanish health authority, and as a result of new scientific developments, convert him into a principal health agent in the fields of hypertension and risk factors. According to our organizational scheme the treatment of the hypertensive patient is undertaken in the preventive cardiology outpatient unit in conjunction with other hospital medical branches and the Family physician. This is backed up by a nursing team that selects the patients on entrance and carries out routine post-therapy.

[Heart effect of arterial hypertension. Heart hypertrophy as a risk factor. Study technics (electrocardiogram, echocardiography, exercise test and Holter]. / Repercusión cardíaca de la hipertensión arterial. Hipertrofia cardíaca como factor de riesgo. Técnicas de estudio (electrocardiograma, ecocardiografía, prueba de esfuerzo y Holter).

Left ventricular hypertrophy, a known consequence of hypertension, is associated with an excess mortality independent of other known cardiovascular risk factors. There are multiple mechanisms in which left ventricular hypertrophy may account for this excess mortality including increased incidence of arrhythmias, systolic an diastolic dysfunction, relative ischemia, and associated coronary artery disease. Diastolic dysfunction, manifested by reduced ventricular distensibility of the hypertrophic left ventricle, appears to be an early characteristic of the hypertensive heart since echocardiographic techniques have demonstrated diastolic filling abnormalities in untreated essential hypertensives even before significant left ventricular hypertrophy appears. The presence of left ventricular hypertrophy is difficult to detect by electrocardiography. Echocardiography seems to be the best non-invasive method for the detection of hypertensive heart disease: it shows early abnormalities of left ventricular compliance, frequently left ventricular hypertrophy and late abnormalities of myocardial contractility.

[Up-dated treatment of arterial hypertension: progressive and individualized. Reduction of the heart mass]. / Tratamiento actualizado de la hipertensión arterial: escalonado e individualizado. Reducción de la masa cardíaca.

The usefulness and limitations of the current medical treatment of high blood pressure are analysed. The latest strategies in the management of hypertension are presented, with emphasis on the treatment of all associated cardiovascular risk factors. This is and important therapeutic goal of Preventive Cardiology. The individualized treatment, that is to say, the selection of the antihypertensive therapy according to the characteristics of each patient, is discussed as an objective of the present therapy. Finally, the new drugs and the recent advances in the classic ones are examined with a special focus on their hemodynamic actions and on their role in left ventricular hypertrophy.

Isosorbide dinitrate sublingual therapy for inferior myocardial infarction: randomized trial to assess infarct size limitation.

To assess the potential of isosorbide dinitrate sublingual therapy for limiting myocardial infarct size, 41 patients with inferior acute myocardial infarction (AMI) were studied. Twenty patients were randomly assigned to the control group and 21 to the treatment group. Patients in the treatment group received 10 mg of isosorbide dinitrate every 2 hours for 72 hours. To estimate infarct size, QRS scoring, peak creatine kinase (CK) serum levels and CK curves were used. There were no significant differences between the 2 groups in maximal or cumulative activity of CK or QRS score (percent of left ventricle infarcted: 16% in the control group, 17% in the treatment group). In both groups the QRS score increased significantly by 13 hours after AMI, and the increase was highly significant by 19 to 23 hours. Thus, sublingual isosorbide dinitrate at the dosage given did not reduce infarct size in patients with inferior AMI.