Colciencias

INTRODUCCIÓN El uso de cocaína puede generar alteraciones psicomotrices (1). Sin embargo, hay pocos estudios sobre el uso conjunto de cocaína-heroína (speedball) y las alteraciones psicomotrices inducidas de forma aguda en una sala de reducción de daños (2,3). OBJETIVOS Analizar las diferencias psicopatológicas psicomotrices entre el uso agudo de cocaína y de cocaína-heroína en una sala de venopunción. MÉTODOS Este es un estudio observacional realizado en una sala de venopunción entre el 01/01/2009 y 31/05/2021. Se analizaron las diferencias sociodemográficas básicas y variables psicomotrices en función del uso agudo de cocaína o cocaína-heroína intravenosa. Análisis univariantes y bivariantes fueron realizados por cada consumo y no por información individual. RESULTADOS De 3707 episodios de venopunción asistida en la sala, 1079 correspondían a uso de cocaína y 77 a cocaína –heroína (el resto eran usos de heroína). Hay diferencias sociodemográficas y psicopatológicas de carácter motriz entre el uso de cocaína y cocaína-heroína (Tabla 1). CONCLUSIONES El uso concomitante de heroína en usuarios de cocaína podría generar diferencias a nivel psicopatológico. REFERENCIAS 1. Maremmani AG et al. Substance abuse and psychosis. The strange case of opioids. Eur Rev Med Pharmacol Sci. 2014;18(3):287-302. 2. Leri F, Bruneau J, Stewart J. Understanding polydrug use: review of heroin and cocaine co-use. Addiction. 2003 Jan;98(1):7-22. doi: 10.1046/j.1360-0443.2003.00236.x. 3. Roncero C et al. Psychotic symptoms of cocaine self-injectors in a harm reduction program. Subst Abus. 2013;34(2):118-21. doi: 10.1080/08897077.2012.691446.

INTRODUCCION El pronóstico y evolución en el Trastorno por Uso de Alcohol (TUA) y Trastorno Mental (TM) está condicionada por la multifactorialidad: falta de adherencia, recaídas, y complicaciones orgánicas. OBJETIVOS Identificar patología psiquiátrica concomitante. Analizar las tasas de adherencia a consulta y tratamiento. Correlacionar patología psiquiátrica con índices de retención. METODO Estudio descriptivo observacional longitudinal. Referencia muestral: 77 pacientes con TUA de 472 incluidos en Plan de Microeliminación del VHC de San Miguel Adicciones (2017 a 2020). Variables de estudio: sociodemográficas, clínicas y de consumo e indicadores de cumplimiento y retención. RESULTADOS Muestra: 62% hombres y 38% mujeres (34 y 70 años). Inicio del consumo de alcohol entre 15 y 18 años. Presentan Patología Dual 69% mujeres y 42% hombres. 85% de pacientes con TUA presentan un solo TM concomitante (95% hombres, 80% mujeres). Patología psiquiátrica predominante: Trastorno Depresivo 22% (H:53%;M:47%), Trastorno de Ansiedad 7% (H:60%;M:40%), Trastorno Ansioso Depresivo 8% (H:34%;M:66%). Destacar la prevalencia de un 18% de mujeres con Trastorno Psicótico. El 58% de mujeres han realizado uno o más Gesto Autolítico. Acuden por Iniciativa Propia 49%, derivación MAP (25%), Especializada 9%. Trastorno Depresivo: 82% de adherencia a consulta, 47% de retención superior a 6 meses. Trastorno de Ansiedad (20%) y 60% de retención entre 6 y 12 meses. CONCLUSIONES Mujeres con TUA presentan más comorbilidad psiquiátrica. La prevalencia de más de un Trastorno Mental es superior en mujeres. El Trastorno Depresivo es el de mayor incidencia con TUA. Escasa derivación desde los Servicios Especializados. References 1. Corrêa Filho JM, Baltieri DA. Psychosocial and clinical predictors of retention in outpatient alcoholism treatment. Braz J Psychiatry. 2012 -12;34(4):413-21. 2. Graff FS, Morgan TJ, Epstein EE, McCrady BS, Cook SM, Jensen NK, et al. Engagement and retention in outpatient alcoholism treatment for women. Am J Addict. 2009 Jul-Aug;18(4):277-88.

Peroxynitrite is a powerful oxidant formed by the near-diffusion-limited reaction of nitric oxide with superoxide. Large doses of peroxynitrite (> 2 mM) resulted in rapid cell swelling and necrosis of undifferentiated PC12 cells. However, brief exposure to lower concentrations of peroxynitrite (EC50 = 850 microM) intially (3-4 h) caused minimal damage to low-density cultures. By 8 h, cytoplasmic shrinkage with nuclear condensation and fragmentation became increasingly evident. After 24 h, 36% of peroxynitrite-treated cells demonstrated these features associated with apoptosis. In addition, 46% of peroxynitrite-treated cells demonstrated DNA fragmentation (by terminal-deoxynucleotide transferase-mediated dUTP-digoxigenin nick end-labeling) after 7 h, which was inhibited by posttreatment with the endonuclease inhibitor aurintricarboxylic acid. Serum starvation also resulted in apoptosis in control cells (23%), the percentage of which was not altered significantly by peroxynitrite treatment. Although peroxynitrite is known to be toxic to cells, the present study provides a first indication that peroxynitrite induces apoptosis. Furthermore, pretreatment of cells with nerve growth factor or insulin, but not epidermal growth factor, was protective against peroxynitrite-induced apoptosis. However, both acidic and basic fibroblast growth factors greatly increased peroxynitrite-initiated apoptosis, to 63 and 70%, respectively. Thus, specific trophic factors demonstrate differential regulation of peroxynitrite-induced apoptosis in vitro.

The present study reports for the first time the distribution of androgen receptor immunoreactivity (AR-ir) in the human hypothalamus of ten human subjects (five men and five women) ranging in age between 20 years and 39 years using the antibody PG21. Prolonged postmortem delay (72:00 hours) or fixation time (100 days) did not influence the AR-ir. In men, intense nuclear AR-ir was found in neurons of the horizontal limb of the diagonal band of Broca, in neurons of the lateromamillary nucleus (LMN), and in the medial mamillary nucleus (MMN). An intermediate nuclear staining was found in the diagonal band of Broca, sexually dimorphic nucleus of the preoptic area, paraventricular nucleus, suprachiasmatic nucleus, ventromedial nucleus, and infundibular nucleus, whereas weaker labeling was found in the bed nucleus of the stria terminalis, medial preoptic area, dorsal and ventral zones of the periventricular nucleus, supraoptic nucleus, and nucleus basalis of Meynert. In most brain areas, women revealed less staining than men. In the LMN and the MMN, a strong sex difference was found. Cytoplasmic labeling was observed in neurons of both sexes, although women showed a higher variability in the intensity of such staining. However, no sex differences in AR-ir were observed in the bed nucleus of the stria terminalis, the nucleus basalis of Meynert, or the islands of Calleja. Species differences and similarities of the AR-ir distribution are discussed. The present results suggest the participation of androgens in the regulation of various hypothalamic processes that are sexually dimorphic.

OBJECTIVE: Previous studies have suggested that oxidative stress may play a role in the pathophysiology of bipolar disorder (BD). Moreover, recent studies indicate that lithium and valproate exert neuroprotective effects against oxidative stress. We studied the effects of the mood stabilizers lithium and valproate on amphetamine-induced oxidative stress in an animal model of mania. METHODS: In the first model (reversal treatment), adult male Wistar rats received d-amphetamine or saline for 14 days, and between the 8th and 14th days, they were treated with lithium, valproate or saline. In the second model (prevention treatment), rats were pretreated with lithium, valproate or saline, and between the 8th and 14th days, they received d-amphetamine or saline. We assessed locomotor activity with the open-field task. We measured thiobarbituric acid reactive substances (TBARS) and protein carbonyl formation, as parameters of oxidative stress, and superoxide dismutase (SOD) and catalase (CAT), the major antioxidant enzymes, in the prefrontal cortex and hippocampus. RESULTS: Lithium and valproate reversed (reversal treatment model) and prevented (prevention treatment model) amphetamine-induced hyperactivity and reversed and prevented amphetamine-induced TBARS formation in both experiments. However, the co-administration of lithium or valproate with amphetamine increased lipid peroxidation, depending on the brain region and treatment regimen. No changes in protein carbonyl formation were observed. SOD activity varied with different treatment regimens, and CAT activity increased when the index of lipid peroxidation was more robust. CONCLUSION: Our findings suggest that lithium and valproate exert protective effects against amphetamine-induced oxidative stress in vivo, further supporting the hypothesis that oxidative stress may be associated with the pathophysiology of BD.

Monkeys are able to discriminate the difference in frequency between two periodic mechanical vibrations applied sequentially to the fingertips. It has been proposed that this ability is mediated by the periodicity of the responses in the quickly adapting (QA) neurons of the primary somatosensory cortex (S1), instead of the average firing rates. We recorded from QA neurons of S1 while monkeys performed the vibrotactile discrimination task. We found that the periodic mechanical vibrations can be represented both in the periodicity and in the firing rate responses to varying degrees across the QA neuronal population. We then computed neurometric functions by using both the periodicity and the firing rate and sought to determine which of these two measures is associated with the psychophysical performance. We found that neurometric thresholds based on the firing rate are very similar to the animal's psychometric thresholds whereas neurometric thresholds based on periodicity are far lower than those thresholds. These results indicate that an observer could solve this task with a precision similar to that of the monkey, based only on the firing rate produced during the stimulus periods.

Seven methods of diagnosing leishmaniasis were compared in 177 patients presenting with lesions of the skin (165) or mucosa (12) in Tumaco and Cali, Colombia. The three methods of visualizing amastigotes in tissue samples (histological staining of tissue sections, impression smears of punch biopsies, and smears of dermal scraping from slits in the lesion margins) were less sensitive than the four Leishmania isolation methods (aspiration of lesion border cultured in biphasic media, aspirate inoculated into hamster nasal tissue, culture of punch biopsy macerate, and hamster inoculation of macerate). The aspirate-culture and biopsy-hamster methods employed in this study proved most sensitive of the four methods for the recovery of parasites. The combined overall sensitivity of the 7 methods was 67% for all enrolled patients and 75% for Montenegro skin test-positive patients. The individual sensitivities for the methods for all patients and Montenegro-positive positive, patients, respectively, were: histopathology 14% and 16%, impression smear 19% and 21%, dermal scraping 22% and 26%, aspirate-culture 58% and 64%, aspirate-hamster 38% and 41%, biopsy-culture 50% and 55%, and biopsy-hamster 52% and 57%. All methods were less sensitive in lesions of greater than 6 months duration than in lesions of more recent onset. Mucosal lesions were best diagnosed by the culture or hamster inoculation of a macerated mucosal biopsy. The diagnosis by inoculation of hamsters was achieved within 2 to 12 weeks, a mean of 34.5 days. Promastigotes were seen on Senekjie's medium within 3-8 days.(ABSTRACT TRUNCATED AT 250 WORDS)

One of the main focal points of aging research is the search for treatments that will prevent or ameliorate the learning and memory deficiencies associated with aging. Here we have examined the effects of maintaining mature mice on a long-term intermittent fasting diet (L-IFD). We found that L-IFD enhances learning and consolidation processes. We also assessed the long-term changes in synaptic efficiency in these animals. L-IFD mice showed an increase in low-theta-band oscillations, paired-pulse facilitation, and facilitation of long-term synaptic plasticity in the hippocampus with respect to mice fed ad libitum. In addition, we found an increase in the expression of the NMDA receptor subunit NR2B in some brain areas of L-IFD mice. Specific antagonism of this subunit in the hippocampus reversed the beneficial effects of L-IFD. These data provide a molecular and cellular mechanism by which L-IFD may enhance cognition, ameliorating some aging-associated cognitive deficits.

BACKGROUND: Controversy and a notable paucity of published clinical data best characterize the current knowledge of testosterone-replacement therapy (TRT) for hypogonadism after treatment for early, localized prostate cancer. The objective of this study was to assess the risk of biochemical failure with TRT after treatment of early prostate cancer with permanent transperineal brachytherapy with or without external beam therapy in patients with low serum levels of testosterone and clinical symptoms of hypogonadism. METHODS: Patients who underwent prostate brachytherapy from 1996 to 2004 and received subsequent TRT for symptomatic hypogonadism were reviewed to detail cancer characteristics and treatment as well as pre- and post-TRT serum testosterone and prostate-specific antigen (PSA) values. RESULTS: Thirty-one men received TRT after prostate brachytherapy for 0.5 to 8.5 years (median, 4.5 years), with a follow-up that ranged from 1.5 years to 9.0 years (median, 5.0 years) postbrachytherapy. TRT was started from 0.5 years to 4.5 years (median, 2.0 years) after brachytherapy. Serum total testosterone levels ranged from 30 ng/dL to 255 ng/dL (median, 188 ng/dL) before TRT and rose to 365 ng/dL to 1373 ng/dL (median, 498 ng/dL) on TRT. Transient rises in PSA were observed in 1 patient. The most recent PSA level was <0.1 ng/mL in 23 patients (74.2%), <0.5 ng/mL in 30 patients (96.7%), and <1 ng/mL in 31 patients (100%). No patients stopped TRT because of cancer recurrence or documented cancer progression. CONCLUSIONS: For patients with low serum testosterone levels and symptoms of hypogonadism, TRT may be used with caution and close follow-up after prostate brachytherapy.

In T cells, the PI3K pathway promotes proliferation and survival induced by Ag or growth factors, in part by inactivating the FOXO transcription factor 1. We now report that FOXO1 controls the expression of L-selectin, an essential homing molecule, in human T lymphocytes. This control is already operational in unprimed T cells and involves a transcriptional regulation process that requires the FOXO1 DNA-binding domain. Using transcriptional profiling, we demonstrate that FOXO1 also increases transcripts of EDG1 and EDG6, two sphingosine-1-phosphate receptors that regulate lymphocyte trafficking. Additionally, FOXO1 binds the promoter of the cell quiescence and homing regulator Krüppel-like factor 2 and regulates its expression. Together, these results reveal a new function of FOXO1 in the immune system and suggest that PI3K controls a coordinated network of transcription factors regulating both cell quiescence and homing of human T lymphocytes.

Food anticipatory behavior (FAA) is induced by limiting access to food for a few hours daily. Animals anticipate this scheduled meal event even without the suprachiasmatic nucleus (SCN), the biological clock. Consequently, a food-entrained oscillator has been proposed to be responsible for meal time estimation. Recent studies suggested the dorsomedial hypothalamus (DMH) as the site for this food-entrained oscillator, which has led to considerable controversy in the literature. Herein we demonstrate by means of c-Fos immunohistochemistry that the neuronal activity of the suprachiasmatic nucleus (SCN), which signals the rest phase in nocturnal animals, is reduced when animals anticipate the scheduled food and, simultaneously, neuronal activity within the DMH increases. Using retrograde tracing and confocal analysis, we show that inhibition of SCN neuronal activity is the consequence of activation of GABA-containing neurons in the DMH that project to the SCN. Next, we show that DMH lesions result in a loss or diminution of FAA, simultaneous with increased activity in the SCN. A subsequent lesion of the SCN restored FAA. We conclude that in intact animals, FAA may only occur when the DMH inhibits the activity of the SCN, thus permitting locomotor activity. As a result, FAA originates from a neuronal network comprising an interaction between the DMH and SCN. Moreover, this study shows that the DMH-SCN interaction may serve as an intrahypothalamic system to gate activity instead of rest overriding circadian predetermined temporal patterns.

The present series of investigations was aimed to disclose the possible sites of action of excitatory and inhibitory inputs on tho-interneuron pathway mediating the primary afferent depolarization (PAD) of group I afferents of extensor muscles in the cat spinal cord. To this end we compared the effects produced by stimulation of segmental and descending pathways on the PAD generated either by stimulation of group I fibers of flexor muscles or by intraspinal microstimulation. It was assumed that under the appropriate conditions the PAD produced by intraspinal microstimulation results from the activation of the last-order interneurons in the PAD pathway and may, therefore, allow detection pathway. The PAD of single group I afferent fibers was determined in barbiturate-anesthetized preparations by measuring the test stimulus current required to maintain a constant probability of antidromic firing. This was achieved by means of a feedback system that continuously adjusted the test stimulus current to the required values. The PAD of individual group Ia gastrocnemius soleus (GS) fibers that is produced by activation of the low-threshold afferents of the posterior biceps and semitendinosus nerve was found to be inhibited by conditioning stimulation of the relatively low-threshold cutaneous fibers and also by stimulation of supraspinal structures such as the ipsilateral brain stem reticular formation, the contralateral red nucleus, and the contralateral pyramidal tract. In contrast, the PAD of group Ia fibers produced by microstimulation applied in the intermediate nucleus could be inhibited only by stimulation of the brain stem reticular formation but not by stimulation of the other descending inputs presently tested or by stimulation of cutaneous nerves. PAD of group Ia fibers was produced also by microstimulation applied within the motor nucleus. However, in most fibers the resulting PAD could not be inhibited either by stimulation of the brain stem reticular formation, the red nucleus, the pyramidal tract, or cutaneous nerves. Stimulation of cutaneous and of flexor muscle nerves of the brain stem reticular formation, the red nucleus, and the pyramidal tract all produced PAD of the group Ib GS fibers.(ABSTRACT TRUNCATED AT 400 WORDS)

Written feedback on drafts of a thesis or dissertation is arguably the most important source of input on what is required or expected of thesis-writing students by the academic community. Despite its importance, relatively little is known about what type of information supervisors focus on when giving feedback. This article presents the findings of an exploratory, descriptive study that investigated what supervisors said they focused on when giving feedback. A total of 35 supervisors across three disciplines (Humanities, Sciences/ Mathematics, Commerce) at six New Zealand universities participated in the study. Data were sought from self –report data (written questionnaires and interviews) and samples of feedback given on thesis drafts. The study found that a wide range of beliefs concerning feedback are held by supervisors, that there is little difference in the type of feedback provided by supervisors in the different disciplines and that similar feedback tends to be given to both L1 and L2 students.

Huntington's disease (HD) is a neurodegenerative disorder that mainly affects the projection neurons of the striatum and cerebral cortex. Genetic mouse models of HD have shown that neurons susceptible to the mutation exhibit morphological and electrophysiological dysfunctions before and during development of the behavioral phenotype. We used HD transgenic mouse models to examine inwardly and outwardly rectifying K+ conductances, as well as expression of some related K+ channel subunits. Experiments were conducted in slices and dissociated cells from two mouse models, the R6/2 and TgCAG100, at the beginning and after full development of overt behavioral phenotypes. Striatal medium-sized spiny neurons (MSNs) from symptomatic transgenic mice had increased input resistances, depolarized resting membrane potentials, and reductions in both inwardly and outwardly rectifying K+ currents. These changes were more dramatic in the R6/2 model than in the TgCAG100. Parallel immunofluorescence studies detected decreases in the expression of K+ channel subunit proteins, Kir2.1, Kir2.3, and Kv2.1 in MSNs, which contribute to the formation of the channel ionophores for these currents. Attenuation in K+ conductances and channel subunit expression contribute to altered electrophysiological properties of MSNs and may partially account for selective cellular vulnerability in the striatum.

Spike-triggered averaging of dorsal and ventral root potentials was used in anesthetized cats to disclose possible synaptic connections of spinal interneurons in the intermediate nucleus with afferent fibers and/or motoneurons. With this method we have been able to document the existence of a distinct group of interneurons whose activity was associated with the recording of inhibitory potentials in the ventral roots (iVRPs), but not with negative dorsal root potentials (nDRPs). The iVRPs had mean durations of 60.8 +/- 22.1 ms and latencies between 1.7 and 5.1 ms relative to the onset of the interneuronal spikes. Within this group of neurons it was possible to characterize two categories depending on their responses to segmental inputs. Most type A interneurons were mono- or disynaptically activated by group I muscle afferents and polysynaptically by low threshold (1.08-1.69 X T) cutaneous fibers. Type B interneurons were instead polysynaptically activated by group II muscle and by cutaneous fibers with thresholds ranging from 1.02 to 3.1 X T. Whenever tested, both type A and B interneurons could be antidromically activated from Clarke's columns. There was a second group of interneurons whose activity was associated with the generation of both iVRPs and nDRPs. These potentials had mean durations of 107.5 +/- 35.6 and 131.5 +/- 32 ms, respectively, and onset latencies between 1.7 and 6.1 ms. The interneurons belonging to this group, which appear not to send axonal projections to Clarke's column, could be classified in three categories depending on their responses to peripheral inputs. Type C interneurons responded mono- or disynaptically to group I muscle volleys and polysynaptically to intermediate threshold (1.22-2.7 X T) cutaneous afferents. Type D interneurons were polysynaptically activated by group II muscle afferents (2.3-8.5 X T) and by intermediate threshold (1.4-3 X T) cutaneous fibers and type E interneurons only by group I muscle afferents with mono- or disynaptic latencies. A third group of interneurons produced nDRPs without iVRPs. The nDRPs had onset latencies varying from 1.9 to 6.2 ms and mean durations of 130.0 +/- 34.6 ms. These neurons (type F) showed spontaneous and evoked bursts of activity and were not antidromically activated from Clarke's column. They responded to stimulation of low- and intermediate-threshold cutaneous fibers (1.04-2.9 X T) with mono- and polysynaptic latencies, but not by group I muscle fibers. Type F interneurons appear to be located in more superficial layers than all the other interneurons.(ABSTRACT TRUNCATED AT 400 WORDS)

Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a "Green List of Species" (now the IUCN Green Status of Species). A draft Green Status framework for assessing species' progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement against benchmarks of species' viability, functionality, and preimpact distribution) to determine current species recovery status (herein species recovery score) and application of that method to estimate past and potential future impacts of conservation based on 4 metrics (conservation legacy, conservation dependence, conservation gain, and recovery potential). We tested the framework with 181 species representing diverse taxa, life histories, biomes, and IUCN Red List categories (extinction risk). Based on the observed distribution of species' recovery scores, we propose the following species recovery categories: fully recovered, slightly depleted, moderately depleted, largely depleted, critically depleted, extinct in the wild, and indeterminate. Fifty-nine percent of tested species were considered largely or critically depleted. Although there was a negative relationship between extinction risk and species recovery score, variation was considerable. Some species in lower risk categories were assessed as farther from recovery than those at higher risk. This emphasizes that species recovery is conceptually different from extinction risk and reinforces the utility of the IUCN Green Status of Species to more fully understand species conservation status. Although extinction risk did not predict conservation legacy, conservation dependence, or conservation gain, it was positively correlated with recovery potential. Only 1.7% of tested species were categorized as zero across all 4 of these conservation impact metrics, indicating that conservation has, or will, play a role in improving or maintaining species status for the vast majority of these species. Based on our results, we devised an updated assessment framework that introduces the option of using a dynamic baseline to assess future impacts of conservation over the short term to avoid misleading results which were generated in a small number of cases, and redefines short term as 10 years to better align with conservation planning. These changes are reflected in the IUCN Green Status of Species Standard.

Several studies have demonstrated that the soil of public parks presents an important source of infection which has a significant impact on public health. Children are the main group affected by accidentally ingestion of contaminated soil. This study was performed in order to identify the presence of zoonotic parasites in dog and cat faecal and soil samples from public parks of Madrid, Spain. Six hundred twenty-five and seventy-nine soil and faecal samples (presumably from dogs and cats) respectively were collected from 67 parks. Intestinal parasites were identified in 27 parks (40.3%), which were contamined with Giardia sp. (19.4%), microsporidia (19.4%), Toxocara spp. (16.4%), Cryptosporidium sp. (6%), Entamoeba histolytica (3%) and Ancylostomidae (3%). Combinations of two or more intestinal parasites were found in 11 parks, and it was common to find Giardia and microsporidia together in samples. Intestinal parasites were detected in 18% (112/625) of soil samples. The most frequent parasite species found in the examined soil samples were Toxocara spp. (16.4%), followed by Giardia sp. (4.5%) and Strongyloides sp. larvae (3%). The zoonotic parasites found in the 79 faecal samples were Giardia sp. (17.7%), Cryptosporidium sp. (9%), E. histolytica (2.5%), Trichuris vulpis (1.3%), Toxascaris leonina (1.3%) and microsporidia spores (28%). Microsporidia characterization by amplification of DNA confirmed 10 samples as positive, eight for E. bieneusi and two for E. hellem by PCR. The role of those parasites in the environment are discussed.

This panel had the objective of recommending evidence-based guidelines for the clinical diagnosis of Alzheimer's disease (AD) in Brazil. Guidelines from other countries and papers on the diagnosis of AD in Brazil were systematically evaluated in a thorough research of PUBMED and LILACS databases. The panel concluded that dementia diagnosis should be based on the DSM criteria and AD diagnosis, on the McKhann et al. criteria (NINCDS-ADRDA). The recommended auxiliary tests are: blood cell count, blood urea nitrogen, serum levels of creatinine, free-thyroxine, thyroid-stimulant hormone, albumin, hepatic enzymes, vitamin B12 and calcium, serological tests for syphilis and, for those aged less than 60 years, serological tests for HIV. Cerebrospinal fluid examination is recommended in special situations. Computed tomography (or preferentially magnetic resonance imaging, when available) is mandatory and has the main objective of excluding other diseases. SPECT and EEG are optional diagnostic methods.

Recent studies have shown that the epithelial sodium channel (ENaC) is expressed in vascular tissue. However, the role that ENaC may play in the responses to vasoconstrictors and NO production has yet to be addressed. In this study, the contractile responses of perfused pressurized small-diameter rat mesenteric arteries to phenylephrine and serotonin were reduced by ENaC blockade with amiloride (75.1+/-3.2% and 16.9+/-2.3% of control values, respectively; P<0.01) that was dose dependent (EC(50)=88.9+/-1.6 nmol/L). Incubation with benzamil, another ENaC blocker, had similar effects. alpha, beta, and gamma ENaC were identified in small-diameter rat mesenteric arteries using RT-PCR and Western blot with specific antibodies. In situ hybridization and immunohistochemistry localized ENaC expression to the tunica media and endothelium of small-diameter rat mesenteric arteries. Patch-clamp experiments demonstrated that primary cultures of mesenteric artery endothelial cells expressed amiloride-sensitive sodium currents. Mechanical ablation of the endothelium or inhibition of eNOS with N(omega)-nitro-L-arginine inhibited the reduction in contractility caused by ENaC blockers. ENaC inhibitors increased eNOS phosphorylation (Ser 1177) and Akt phosphorylation (Ser 473). The presence of the phosphoinositide 3-kinase inhibitor LY294002 blunted Akt phosphorylation and eNOS phosphorylation and the decrease in the response to phenylephrine caused by blockers of ENaC, indicating that the phosphoinositide 3-kinase/Akt pathway was activated after ENaC inhibition. Finally, we observed that the effects of blockers of ENaC were flow dependent and that the vasodilatory response to shear stress was enhanced by ENaC blockade. Our results identify a previously unappreciated role for ENaC as a negative modulator of eNOS and NO production in resistance arteries.

Este artículo se enfoca en una revisión tanto de literatura como de experiencias prácticas acerca de los MOOC. Los textos analizados fueron publicados en revistas entre los años 2007 y 2013. Se seleccionaron 268 artículos para este estudio, de los cuales 100 se analizaron en detalle. Los asuntos encontrados en la revisión se utilizaron posteriormente como criterios de análisis de 10 experiencias empíricas sobre MOOC. La literatura estudiada resalta el rápido crecimiento en el interés por comprender los MOOC, sus fundamentos pedagógicos así como la importancia del concepto de lo abierto que se encuentra en ellos. Un nuevo énfasis ha surgido recientemente en la literatura donde los factores institucionales, particularmente aquellos concernientes con la viabilidad financiera, la certificación y la deserción se encuentran resaltados. El análisis de la prácticas actuales muestra que muchos de los temas relevantes expresados en la literatura académica están ausentes no solo de las prácticas relacionadas con las experiencias de aprendizaje basadas en los MOOC sino que se han ignorado como sustento de la implementación de un modelo de enseñanza basada en ellos. Del análisis realizado se concluye que buena parte de la actual oferta de MOOC es tan solo un pálido reflejo de la conceptualización que les dio origen y que se muestra significativa en la literatura. En síntesis, la verdadera esencia del concepto de lo abierto se ha perdido en la práctica.