Neurons in the hilus region of the rat hippocampus are depleted in number by exposure to alcohol during early postnatal life

We have previously shown that exposing rats to a relatively high dose of ethanol during early postnatal life resulted in a deficit in spatial learning ability. This ability is controlled, at least in part, by the hippocampal formation. The purpose of the present study was to determine whether exposure of rats to ethanol during early postnatal life affected the number of specific neurons in the hippocampus. Wistar rats were exposed to a relatively high daily dose of ethanol between postnatal days 10 and 15 by placing them for 3 h each day in a chamber containing ethanol vapor. The blood ethanol concentration was about 430 mg/dl at the end of the exposure period. Groups of ethanol-treated (ET) rats, separation controls (SC), and mother-reared controls (MRC) were anesthetized and killed at 16 days of age by perfusion with phosphate-buffered glutaraldehyde (2.5%). The Cavalieri principle was used to determine the volume of various subdivisions of the hippocampal formation (CA1, CA2+CA3, hilus, and granule cell layer), and the physical disector method was used to estimate the numerical densities of neurons within each subdivision. The total number of neurons was calculated by multiplying estimates of the numerical density with the volume. There were, on average, about 441,000 granule cells in the granule cell layer and 153,000 to 177,000 pyramidal cells in both the CA1 and CA2+CA3 regions in all three treatment groups. In the hilus region, ET rats had about 27,000 neuronal cells. This was significantly fewer than the average of 38,000 such neurons estimated to be present in both MRC and SC animals. Thus, neurons in the hilus region may be particularly vulnerable to the effects of a high dose of ethanol exposure during early postnatal life. (C) 2000 Wiley-Liss, Inc.

Effects of age and alcohol exposure during early life on pyramidal cell numbers in the CA1-CA3 region of the rat hippocampus

We have previously shown that exposing rats to a relatively high dose of ethanol during early postnatal life can result in an alteration in spatial learning ability. The hippocampal formation is known to be involved in the control of this ability. The purpose of the present study was to determine whether exposure of rats to ethanol during early postnatal life had either immediate or delayed effects on the numbers of pyramidal cells in the CA1-CA3 subregion of the hippocampus. Wistar rats were exposed to a relatively high daily dose of ethanol at postnatal day 10-15 by placing them for 3 h/day in a chamber containing ethanol vapor. Groups of ethanol-treated (ET), separation control (SC), and mother-reared control (MRC) rats were anesthetized and killed at 16 and 30 days of age by perfusion with phosphate-buffered 2.5% glutaraldehyde. The Cavalieri principle was used to determine the volumes of the CA1 and CA2+CA3 regions. The physical disector method was used to estimate the numerical density of neurons in each of the subdivisions. The total number of pyramidal cells was calculated by multiplying the appropriate estimates of the numerical density by the volume. There were significant age-related reductions in the total numbers of pyramidal cells at 16-30 days of age irrespective of the groups examined. Ethanol treated rats were found to have slightly but significantly fewer pyramidal cell neurons than either the MRC or SC groups. These observations indicate that pyramidal cells in the hippocampus may be vulnerable to a relatively high dose of ethanol exposure during this short period of early postnatal life. (C) 2003 Wiley-Liss, Inc.

Effects of postnatal protein malnutrition on learning and memory procedures

Protein malnutrition induces structural, neurochemical and functional changes in the central nervous system leading to alterations in cognitive and behavioral development of rats. The aim of this work was to investigate the effects of postnatal protein malnutrition on learning and memory tasks. Previously malnourished (6% protein) and well-nourished rats (16% protein) were tested in three experiments: working memory tasks in the Morris water maze (Experiment I), recognition memory of objects (Experiment II), and working memory in the water T-maze (Experiment III). The results showed higher escape latencies in malnourished animals in Experiment I, lower recognition indexes of malnourished animals in Experiment II, and no differences due to diet in Experiment III. It is suggested that protein malnutrition imposed on early life of rats can produce impairments on both working memory in the Morris maze and recognition memory in the open field tests.

Effect of early malnutrition and environmental stimulation in the performance of rats in the elevated plus maze

Malnourished rats since birth (mothers fed on 6% of protein) or controlled ones (16% of protein), half of each group received environmental stimulation (ES) from the age of 0-35th day, were studied. The performance in the elevated plus maze (EPM) was assessed on the last day. ES increased time spent and also the entries into open arms of EPM, but malnourished non-stimulated rats visited more segments near the central area than the distant ones. Data suggests an anxiolytic effect of ES which is less evident in malnourished rats. (C) 2009 Elsevier B.V. All rights reserved.

Continence, potency and oncological outcomes after robotic-assisted radical prostatectomy: early trifecta results of a high-volume surgeon

OBJECTIVE center dot To evaluate early trifecta outcomes after robotic-assisted radical prostatectomy (RARP) performed by a high-volume surgeon. PATIENTS AND METHODS center dot We evaluated prospectively 1100 consecutive patients who underwent RARP performed by one surgeon. In all, 541 men were considered potent before RARP; of these 404 underwent bilateral full nerve sparing and were included in this analysis. center dot Baseline and postoperative urinary and sexual functions were assessed using self-administered validated questionnaires. center dot Postoperative continence was defined as the use of no pads; potency was defined as the ability to achieve and maintain satisfactory erections for sexual intercourse > 50% of times, with or without the use of oral phosphodiesterase type 5 inhibitors; Biochemical recurrence (BCR) was defined as two consecutive PSA levels of > 0.2 ng/mL after RARP. center dot Results were compared between three age groups: Group 1, < 55 years, Group 2, 56-65 years and Group 3, > 65 years. RESULTS center dot The trifecta rates at 6 weeks, 3, 6, 12, and 18 months after RARP were 42.8%, 65.3%, 80.3%, 86% and 91%, respectively. center dot There were no statistically significant differences in the continence and BCR-free rates between the three age groups at all postoperative intervals analysed. center dot Nevertheless, younger men had higher potency rates and shorter time to recovery of sexual function when compared with older men at 6 weeks, 3, 6 and 12 months after RARP (P < 0.01 at all time points). center dot Similarly, younger men also had a shorter time to achieving the trifecta and had higher trifecta rates at 6 weeks, 3 and 6 months after RARP compared with older men (P < 0.01 at all time points). CONCLUSION center dot RARP offers excellent short-term trifecta outcomes when performed by an experienced surgeon. center dot Younger men had a shorter time to achieving the trifecta and higher overall trifecta rates when compared with older men at 6 weeks, 3 and 6 months after RARP.

Single Intranasal Administration of 1-Methyl-4-Phenyl-1,2,3,6-Tetrahydropyridine in C57BL/6 Mice Models Early Preclinical Phase of Parkinson`s Disease

Many studies have shown that deficits in olfactory and cognitive functions precede the classical motor symptoms seen in Parkinson`s disease (PD) and that olfactory testing may contribute to the early diagnosis of this disorder. Although the primary cause of PD is still unknown, epidemiological studies have revealed that its incidence is increased in consequence of exposure to certain environmental toxins. In this study, most of the impairments presented by C57BL/6 mice infused with a single intranasal (i.n.) administration of the proneurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (1 mg/nostril) were similar to those observed during the early phase of PD, when a moderate loss of nigral dopamine neurons results in olfactory and memory deficits with no major motor impairments. Such infusion decreased the levels of the enzyme tyrosine hydroxylase in the olfactory bulb, striatum, and substantia nigra by means of apoptotic mechanisms, reducing dopamine concentration in different brain structures such as olfactory bulb, striatum, and prefrontal cortex, but not in the hippocampus. These findings reinforce the notion that the olfactory system represents a particularly sensitive route for the transport of neurotoxins into the central nervous system that may be related to the etiology of PD. These results also provide new insights in experimental models of PD, indicating that the i.n. administration of MPTP represents a valuable mouse model for the study of the early stages of PD and for testing new therapeutic strategies to restore sensorial and cognitive processes in PD.

Mice with genetic deletion of the heparin-binding growth factor midkine exhibit early preclinical features of Parkinson`s disease

There is considerable evidence showing that the neurodegenerative processes that lead to sporadic Parkinson`s disease (PD) begin many years before the appearance of the characteristic motor symptoms and that impairments in olfactory, cognitive and motor functions are associated with time-dependent disruption of dopaminergic neurotransmission in different brain areas. Midkine is a 13-kDa retinoic acid-induced heparin-binding growth factor involved in many biological processes in the central nervous system such as cell migration, neurogenesis and tissue repair. The abnormal midkine expression may be associated with neurochemical dysfunction in the dopaminergic system and cognitive impairments in rodents. Here, we employed adult midkine knockout mice (Mdk(-/-)) to further investigate the relevance of midkine in dopaminergic neurotransmission and in olfactory, cognitive and motor functions. Mdk(/-) mice displayed pronounced impairments in their olfactory discrimination ability and short-term social recognition memory with no gross motor alterations. Moreover, the genetic deletion of midkine decreased the expression of the enzyme tyrosine hydroxylase in the substantia nigra reducing partially the levels of dopamine and its metabolites in the olfactory bulb and striatum of mice. These findings indicate that the genetic deletion of midkine causes a partial loss of dopaminergic neurons and depletion of dopamine, resulting in olfactory and memory deficits with no major motor impairments. Therefore, Mdk(-/-) mice may represent a promising animal model for the study of the early stages of PD and for testing new therapeutic strategies to restore sensorial and cognitive processes in PD.

Implications of missed opportunities for learning and assessment in design and technology education

Supporting student learning can be difficult, especially within open-ended or loosely structured activities, often seen as valuable for promoting student autonomy in many curriculum areas and contexts. This paper reports an investigation into the experiences of three teachers who implemented design and technology education ideas in their primary school classrooms for the first time. The teachers did not capitalise upon many of the opportunities for scaffolding their students' learning within the open-ended activities they implemented. Limitations of the teachers' conceptual and procedural knowledge of design and technology were elements that influenced their early experiences. The study has implications for professional developers planning programs in newly introduced areas of the curriculum to support teachers in supporting learning within open-ended and loosely structured problem solving activities. (C) 2001 Elsevier Science Ltd. All rights reserved.

Reciprocal changes in forebrain contents of glycogen and of glutamate/glutamine during early memory consolidation in the day-old chick

Passive avoidance learning is with advantage studied in day-old chicks trained to distinguish between beads of two different colors, of which one at training was associated with aversive taste. During the first 30-min post-training, two periods of glutamate release occur in the forebrain. One period is immediately after the aversive experience, when glutamate release is confined to the left hemisphere. A second release, 30 min later, may be bilateral, perhaps with preponderance of the right hemisphere. The present study showed increased pool sizes of glutamate and glutamine, specifically in the left hemisphere, at the time when the first glutamate release occurs, indicating de novo synthesis of glutamate/glutamine from glucose or glycogen, which are the only possible substrates. Behavioral evidence that memory is extinguished by intracranial administration at this time of iodoacetate, an inhibitor of glycolysis and glycogenolysis, and that the extinction of memory is counteracted by injection of glutamine, supports this concept. A decrease in forebrain glycogen of similar magnitude and coinciding with the increase in glutamate and glutamine suggests that glycogen rather than glucose is the main source of newly synthesized glutamate/glutamine. The second activation of glutamatergic activity 30 min after training, when memory is consolidated into stable, long-term memory, is associated with a bilateral increase in pool size of glutamate/glutamine. No glycogenolysis was observed at this time, but again there is a temporal correlation with sensitivity to inhibition by iodoacetate and rescue by glutamine, indicating the importance of de novo synthesis of glutamate/glutamine from glucose or glycogen. (C) 2003 Elsevier B.V All rights reserved.

The emergence of a curriculum model for online learning in a context of late investment in distance education

ECER 2015 "Education and Transition - Contributions from Educational Research", Corvinus University of Budapest from 7 to 11 September 2015.

Learning with tangible interfaces

Trabalho apresentado no âmbito do Mestrado em Engenharia Informática, como requisito parcial para obtenção do grau de Mestre em Engenharia Informática

Math without stress – an open online learning project

MOOC (as an acronym for Massive Open Online Courses) are a quite new model for the delivery of online learning to students. As “Massive” and “Online”, these courses are proposed to be accessible to many more learners than would be possible through conventional teaching. As “Open” they are (frequently) free of charge and participation is not limited by the geographical situation of the learners, creating new learning opportunities in Higher Education Institutions (HEI). In this paper we describe a recently started project “Matemática 100 STRESS” (Math Without STRESS) integrated in the e-IPP project | e-Learning Unit of Porto’s Polytechnic Institute (IPP) which has created its own MOOC platform and launched its first course – Probabilities and Combinatorics – in early June/2014. In this MOOC development were involved several lecturers from four of the seven IPP schools.

Math without stress: an open online learning project

MOOC (as an acronym for Massive Open Online Courses) are a quite new model for the delivery of online learning to students. As “Massive” and “Online”, these courses are proposed to be accessible to many more learners than would be possible through conventional teaching. As “Open” they are (frequently) free of charge and participation is not limited by the geographical situation of the learners, creating new learning opportunities in Higher Education Institutions (HEI). In this paper we describe a recently started project “Matemática 100 STRESS” (Math Without STRESS) integrated in the e-IPP project | e-Learning Unit of Porto’s Polytechnic Institute (IPP) which has created its own MOOC platform and launched its first course – Probabilities and Combinatorics – in early June/2014. In this MOOC development were involved several lecturers from four of the seven IPP schools.

High-Content Analysis of Breast Cancer Using Single-Cell Deep Transfer Learning

High-content analysis has revolutionized cancer drug discovery by identifying substances that alter the phenotype of a cell, which prevents tumor growth and metastasis. The high-resolution biofluorescence images from assays allow precise quantitative measures enabling the distinction of small molecules of a host cell from a tumor. In this work, we are particularly interested in the application of deep neural networks (DNNs), a cutting-edge machine learning method, to the classification of compounds in chemical mechanisms of action (MOAs). Compound classification has been performed using image-based profiling methods sometimes combined with feature reduction methods such as principal component analysis or factor analysis. In this article, we map the input features of each cell to a particular MOA class without using any treatment-level profiles or feature reduction methods. To the best of our knowledge, this is the first application of DNN in this domain, leveraging single-cell information. Furthermore, we use deep transfer learning (DTL) to alleviate the intensive and computational demanding effort of searching the huge parameter's space of a DNN. Results show that using this approach, we obtain a 30% speedup and a 2% accuracy improvement.

Cross-language influences on new second language vocabulary acquisition: the effect of learning method

Dissertação de mestrado integrado em Psicologia