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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

American Journal of Neuroscience

Endogenous Calcitonin Gene-Related Peptide (CGRP) stored in perivascular nerve fibers around the cerebral arteries mediates vasodilation and regulates cerebral blood flow under physiological conditions. Increased levels of CGRP have been continually reported in patients with migraine, but the role of CGRP in the pathophysiology of Subarachnoid Hemorrhage (SAH) has not yet been sufficiently evaluated. Over 10 days, serum was prospectively collected from 33 consecutive patients (17 women, 16 men; mean age 52.8 years) with spontaneous non-traumatic SAH. All patients were graded III or IV according to the Fisher Score. CGRP levels were determined by means of an Enzyme-Immunosorbent Assay (EIA). CGRP concentrations were correlated to (1) the anatomical localization of the aneurysm (anterior circulation or posterior circulation), (2) the treatment modality (clipped group, coiled group, or untreated group) and (3) the rate of ischemia determined by computed tomography (ischemia group, non-ischemia group, or iatrogenic ischemia group). (1) Anatomical localization: CGRP levels were significantly higher in patients with a ruptured aneurysm of the anterior circulation (p<0.001). (2) Treatment modality: CGRP levels differed significantly between the groups (coil group, clip group, or untreated group; p<0.001). The highest levels of CGRP were detected in the coil group and the lowest levels in the untreated group. About (3) Ischemia: CGRP levels differed significantly between the three groups (ischemia group, non-ischemia group, or iatrogenic ischemia group; p = 0.038). The highest levels of CGRP were found in the ischemia group. The maximum levels of CGRP in serum were found for patients with a ruptured aneurysm of the anterior circulation and subsequent ischemia treated by endovascular coiling. These findings support the theory that CGRP is produced and excessively released to counteract cerebral vasospasm and subsequent ischemia. Presumably, the serum levels of CGRP are affected by the anatomical localization of the aneurysm and can be stimulated by any endoluminal manipulation of the parent artery.

http://www.thescipub.com/abstract/10.3844/amjnsp.2014.10.17 2014/06/29 - 18:49

Names function as sensory representations, but the relationship between names and sensory stimuli/responses remains unclear. This study proposes the existence of a class of stimulus-response pathways, the name pathway, where a name is a reproducible and communicable symbol and the name pathway is one where the same name is both the stimulus and the response. Once a stimulus-response “name” pathway is formed as a result of reinforcement-based learning and in concert with the formation of the associated stimulus-response “sensory” pathway for a named object, act or process, Hebbian cross-pathway connectivity between the sensory and name pathways allows each pathway’s stimulus to activate the other’s response. The model proposes that every higher-order cognitive function exists only because it was named and that each such function may be defined mechanistically to be the outcome of the “recognition,” “interpretation,” and “retrieval” of sensory experiences from networks of names for that function.

http://www.thescipub.com/abstract/10.3844/amjnsp.2014.1.9 2014/04/04 - 16:33

One of the most neurotransmission system consistently linked with fear response is GABAergic system. GABA through GABAB receptor can influence fear response. The aim of the present investigation was to examine the effect of IP injection of baclofen (GABAB agonist) and CGP35348 (GABAB antagonist) along with EMF exposure on frequency of fear response. Fifty adult male rats weighing 180-200 g were used. Animals were divided in ten groups, of which five groups were exposed to ELF-EMF for 30 days at 8 h day-1 in a solenoid, creating an electromagnetic field of 500 µT by a 50 Hz electrical current. Animals were then treated with various doses of baclofen and CGP35348 before being exposed to electrical shock. Each animal were received 100 electrical shocks every session. After shock induction, the fear response was determined by monitoring the reaction of shocked animals to a normal rat which was placed in the electroshock chamber. Data was analyzed by Mann-Whitney test. Significant level was considered to be p<0.05. It was shown that injection of baclofen and CGP35348 did not induce any significant change in fear response in without EMF groups, while both of baclofen and CGP35348 significantly increased frequency of fear response in EMF exposure male rats. Results indicated that GABAB receptors and EMF exposure possibly involved in the modulation of fear response.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.56.59 2013/06/09 - 16:31

Reversible protein phosphorylation is a common and important form of protein posttranslational modification which determines the proteins’ activities, substrate specificity and inhibitions or degradations, depending on the specific amino acid residue, or combination of residues, being targeted. While protein phosphorylations by kinases have been well studied, the importance of protein dephosphorylation by phosphatases has emerged over the past two decades in numerous cell functions, including cell cycle, development, regulation of signal transduction pathways, mitochondrial fussion and fission and disease states of cells. So far, there are five classes of phosphatases: tyrosine-specific phosphatases, serine/threonine specific phosphatases, dual specificity phosphatases, histidine phosphatase and lipid phosphatase. The subject of this review, Protein Phosphatase 2 (PP2, aka PP2A), is a member of the serine/threonine specific phosphatases which dephosphorylate a wide range of proteins including many of the phosphatases and kinases. In eukaryotic proteins, 86 and 12% are phosphorylated on Ser and Thr, respectively and the reversible phosphorylation of these proteins is key to their dynamic functions. The research done on PP2A has exploded in recent years and there are many excellent detail reviews each with a specific PP2A topic. This article presents a brief overview of PP2A functions in four aspects: Their substrate specificity, roles in Tau hyperphosphorylation, roles in mitochondria fusion and fission and nine examples of their roles in neuronal functions.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.46.55 2013/06/09 - 16:31

In neurophysiological studies on learning and memory, L-glutamate receptors especially N-Methyl, D-Aspartate glutamate (NMDA) receptors have a major role in different aspect of the learning and memory. Two sites of mammalian brain that show high density of these receptors are CA1 region of hippocampus and Purkinje cell layer of cerebellum. Twenty four Sprague-Dawley rats were used in 4 groups: control 1 (intact without learning); control 2 (intact with learning); experimental 1 (castration without learning) and experimental 2 (castration with learning). A shuttle box apparatus used for passive avoidance learning procedure. Immunohistochemical procedure was used for determination of NR1 subunit of NMDA receptor. Photoshop software was used for determination of color intensity. Data were analyzed by student t-test and one-way ANOVA, Tucky test as post-hoc test was used. The level of significant was considered P<0.05. Immunohistological finding of this experiment indicates that castration has a negative effect on density of NR1 subunit of NMDA receptors in two brain regions. Other finding of this study showed that passive avoidance learning significantly increased density of NR1 subunit of NMDA receptors in two brain regions. These results indicated that the sex hormone can modulate function and expression of the NR1 subunit of NMDA receptor in CA1 region of hippocampus and Purkinje cell layer of cerebellum.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.39.45 2013/06/09 - 16:31

Traumatic Spinal Cord Injury (SCI) results in both focal and diffuse spinal cord pathologies that are exacerbated by an inflammatory response after the initial injury. Resident and infiltrating immune cells contribute significantly to the growth-refractory environment near the lesion and can intensify damage to spared tissue, resulting in impaired spontaneous functional recovery. Numerous studies have demonstrated that several immunomodulatory therapies administered after experimental SCI may be beneficial in promoting functional recovery. In this review, we focus on the therapeutic potential of the most abundant immune-based therapies e.g., rolipram, liposomal clodronate and TNF-α based therapy including etanercept, thalidomide and adenosine A1 receptor therapy their contribution to eliminating secondary damage and promoting recovery after SCI.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.25.38 2013/06/09 - 16:31

Traumatic Brain Injury (TBI) is a devastating clinical condition that often causes permanent incapacity, especially in the younger population. The clinical relevant of TBI justifies the scientific interest in the pathophysiology of TBI, as well as in protective effects and development of treatment options. Stem cells have the ability to induce neuroprotection and neural repair inflammatory suppression, causing tissue reconstruction completely or partially damaged cells to preventing cell death to evolve. However the neurological improvement observed in preclinical studies and clinical tests based on neurological and behavioral disorders and the mechanism of action of stem cells remains unknown. In this study the authors discuss the current status of using stem cells to treat TBI, including the basic cell types and potential mechanisms of action, preclinical data and points out lack of studies and hurdles for clinical application. The authors also focusing on the recent demonstration that neurogenesis occurs in all mammals throughout adult life, although at a low rate, is possible to induce neurogenesis de novo in the adult mammalian brain, particularly in the neocortex where it does not normally occur and that it may become possible to manipulate endogenous multipotent precursors in situ to replace lost or damaged neurons. Elucidation of the relevant molecular controls may both allow control over transplanted precursor cells and potentially allow the development of neuronal replacement therapies for neurodegenerative disease and other central nervous system injuries that do not require transplantation of exogenous cells. Discuss strategies of enhance the neurogenesis (for example by exogenous tropics factor administration) and the transplantation of different types of neural progenitor cells after TBI. Each strategy is discussed with an emphasis on highlighting the progress and limiting factors relevant to the development of clinical trials of cellular replacement therapy for severe TBI in humans.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.13.24 2013/06/09 - 16:31

It is estimated that approximately 2.5 million people are affected by Spinal Cord Injury (SCI), with more than 130,000 new cases reported each year (International Campaign for Cures of Spinal Cord Injury Paralysis). Although there is currently no cure for SCI, various strategies including rehabilitative, cellular and molecular therapies have been tested in a variety of animal models. But questions remain as to the validity of animal models and whether they relate to the clinical conditions found in humans. This review aims to look at the different and most current models that are used to study SCI and their potential uses in mimicking the human condition. Several different animals models have been developed to study the problems of SCI, allowing exploration of mechanisms and properties of specific pathways such as; the MAPK pathway and spinal cord diseases such as; Syringomyelia and Central Cord Syndrome to name a few to be elucidated. SCI is complicated by cavitation and a glial scar that lines the cavity, reducing the possibility of axon regeneration. Mammalian models, particularly in mice and rats, have been used for many years to study the impact of SCI and potential therapies, however, questions remain as to the validity of these models and their potential usefulness.

http://www.thescipub.com/abstract/10.3844/amjnsp.2013.1.12 2013/03/28 - 11:14

Because of their ability to modulate the Gamma Aminobutyric Acid (GABA) a receptor complex, the principal aim of the current work is to assess two essential heavy metals: Iron (Fe) and zinc (Zn) by atomic absorption in different brain areas of stressed rats. To do so, we investigated the effect of acute immobilization stress (single 1-hour session) on the distribution and the densities of GABAA receptors as well as the concentrations of Zn and Fe in several rat brain regions of the stressed rats. Animals were randomly assigned to either control or stress conditions and changes in specific binding of the GABAA receptor as labelled with T-Butylbicyclophosphonothionate (TBPS) (ligand useful for GABAA receptor) were assessed by in vitro quantitative autoradiography with the aid of a computer-assisted image analysis system whereas the assessment of Fe and Zn concentrations was done by atomic absorption spectrophotometry. Exposure to 1h immobilization stress led to a significant increase in [35S]-TBPS binding site density in stressed rats compared to controls (30-40% increase in cortex, hypothalamus, hippocampus and substatntia nigra). In the other analyzed brain structures, specific binding of [35S]-TBPS remained unchanged in stressed rats. The spectrophotometer analysis showed significant decrease in Zn levels in the whole forebrain structures as well as the mesencephalon of stressed rats. The striking differences are noticed in hippocampus and mesencephalon. Furthermore, Fe endogenous concentrations display similar pattern following stress. The present study demonstrates that immobilization stress induces an increase in the density of GABAA receptors concomitant to a reduction of Zn and Fe content in the stress sensitive rat brain structures. Besides supporting the alteration of the modulatory function occurring at the GABAA receptor level after stress, our data also reveal that the measured brain concentrations of the investigated heavy metals remain not sufficient to efficiently modulate the activity of with efficacy such complex receptor. This could explain the higher densities of GABAA receptors observed after acute stress.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.79.86 2012/09/15 - 10:31

Somatostatin has been reported to modulate GABAA receptor complex in many brain structures. This study was conducted to investigate somatostatin modulation of the GABAA receptor binding in several rat diencephalic structures, focusing primarily on the thalamus, as this structure plays important roles. Animals were assigned to control conditions. Changes in specific binding of GABAA receptor as labelled with [35S]t-Butylbicyclophosphorothionate (TBPS) were assessed by in vitro quantitative autoradiography with the aid of a computer assisted image analysis system. Our results reveal the presence of higher densities in several thalamic structures located principally in the part of thalamus. We demonstrate for the first time the presence of a modulatory effect of somatostatin on the GABAA receptor complex in this brain region in rats. Indeed, the peptide affected in a concentration-dependent manner; the binding of [35S]-Tertiary Butylbicyclophosphorothionate (TBPS) to the convulsant site of the GABAA receptor complex in thalamic structures with an affinity in the micromolar range (10-3 to 3.10-6M). The inhibitory effect of somatostatin is observed in all thalamic structures analyzed. The absence of a specific region effect of somatostatin on the binding of [35S]-TBPS, suggests the presence of a homogenous subunit GABAA receptor composition. Furthermore, GABA and muscimol, a GABAA receptor agonist, enhanced the affinity of somatostatin effect on [35S]-TBPS. This suggests that somatostatin allosterically modifies [35S]-TBPS binding through a mechanism similar to that of GABA.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.71.78 2012/09/14 - 10:23

Animals have evolved several chemosensory systems for detecting potentially dangerous foods in the environment. Activation of specific sensory cells within these chemosensory systems usually elicits an aversive behavioral response, leading to avoidance of the noxious foods. Blowflies respond to sugars, salts and water through the activation of specific chemoreceptor neurons in the antennal, labellar and tarsal chemosensillae. These insects also detect deterrent stimuli with the so called fifth or deterrent cell. Using forensically important flies (blowflies) as a model organism, the question was if these flies have the ability to detect the nutritional value of corpses when injected with different doses of morphine. In the attempt to gain information on the mechanisms underlying reception of noxious and repellent compounds, electrophysiological and behavioral experiments have been performed to confirm the hypothesis that morphine sulfate has a repellent effect on fly attraction to corpse. Electrophysiological and behavioral results indicate that morphine sulfate activate the fifth cell in the chemosensillae. In field behavioral test, carrions injected with doses of morphine sulfate, are colonized later with flies than morphine-free carrions. This finding is in accordance with the spike frequency elevation observed for the fifth cell activity. The prevailing activation of the deterrent cell by morphine sulfate is directly coupled with a coherent behavioral output. Therefore, comparison of behavioral and electrophysiological data, affirm that blowfly identify morphine sulfate as a deterrent stimuli by activation of the fifth cell.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.63.70 2012/09/05 - 21:40

Fibroblast Growth Factors (FGFs) have been implicated in numerous cellular processes including proliferation, migration, differentiation and neuronal survival. One of these growth factors, Fibroblast Growth Factor 2 (FGF2), is apparently implicated in the ability of the adult salamander (Pleurodeles waltlii) to recover locomotion following complete transection of the spinal cord. In a previous study, we reported up regulation of FGF2 during regeneration of damaged axons and recovery of hind limb locomotion. In this study reported here, we investigated the spatial distribution of FGFR2-one of the receptors that mediate the effects of FGF2-using a variety of techniques, namely, western blot, immunohistochemistry and in situ hybridization. We find that in intact animals FGFR2 is mainly expressed in the most posterior part of body Spinal Cord (SC3) specifically in neurons. However, lesioning the spinal cord produces increased expression in Brainstem (BS) neurons and decreased expression in posterior parts of the spinal cord not only in neurons but also in the neuroglial ependymal cells lining the central canal. This suggests that FGF2 simultaneously activates FGFR1 and 2, perhaps at different points in the regeneration process and thus FGFR2 might play at least an indirect role in the spontaneous regeneration observed in this species and might be relevant to the treatment of spinal cord lesions in humans. Verification of this possibility will require studies of additional time points

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.41.53 2012/09/04 - 23:17

Alzheimer’s disease, the most prevalent type of dementia, affects the life of elderly, to such extent that it impairs the ability to perform routine functions as well. The impairment of normal functions not only affects the patients but the family members as well. It is difficult to make a definitive diagnosis; hence some clinical and psychological tools are used to diagnose the disease. MRI can be used effectively in this regard as well. However in the recent years, much work has been done to devise a biochemical marker which can be effective for definitive and early diagnosis. Amyloid beta and CSF tau proteins have been the most successful by far in confirming the Alzheimer’s disease pathology. Other biomarkers such as neuronal markers are also important as they particularly show the pathology in brain. It is recommended by National Institute on Aging to include amyloid beta and markers of neuronal pathology in tools for clinical diagnosis of the disease; even so, more work is required in this regard. It is expected that in future, these markers will be essential to diagnose the disease.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.54.62 2012/09/04 - 23:17

One neurochemical system most consistently linked with aggression is the GABAergic system. The aim of the present investigation was to examine the effect of injection of baclofen (GABAB agonist) and CGP35348 (GABAB antagonist) in the Central Amygdaloid (CA) and Medial Amygdaloid (MA) nuclei of the amygdala on offensive aggression behavior in the animal model. Sixty six adult male rats weighing 180-200g were used. Cannula was implanted into each ac and or am nuclei of amygdala using stereotaxic method. Each animal received 100 electrical shocks every session. After electrical shock, another rat was placed in the electroshock chamber and the animals were observed for various aggressive behaviors. Data were analyzed by Student’s T test and one way ANOVA and Tukey’s test as the post-hoc test. Significant level was considered to be p<0.05. It was shown that injection of baclofen into the am nucleus of amygdala led to a significant increase in offensive aggression behavior, whereas baclofen injection into the ac nucleus of amygdala led to a significant decrease in offensive aggression behavior. Injection of CGP35348 into the am nucleus of amygdala caused a significant decrease in aggressive behavior, but its injection into the ac nucleus of amygdala induced a significant increase in offensive aggression behavior. Results indicated that GABAB receptors in the ac and am nuclei of amygdala are possibly involved in the modulation of offensive aggression behavior.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.25.31 2012/09/03 - 21:28

Problem statement: Glia cells outnumber neurons but their role in synaptic transmission is still matter of debate. The recycling of Glutamate, the main excitatory neurotransmitter, carried out by the glutamate/glutamine shuttle, requires the involvement of glia, suggesting their involvement in neurotransmission. Approach: This review focuses on novel functions of glia proteins involved in this cycle. Results: An activity-dependent interaction of glial glutamate transporters, the Na+/K+ ATPase, the glutamine and glucose transporters might support glutamatergic neurotransmission. Conclusion: Glia cells that surround glutamatergic contacts, respond to synaptic activity and modify accordingly, the amount and function of the proteins involved in their interaction with neurons thus assuring a synaptic transmission.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.32.38 2012/09/03 - 21:28

Problem statement: At present, the novel agent that is effective, cheap and easy to approach for treating male sexual dysfunction is required due to the current poor therapeutic efficacy. Though Moringa oleifera is reputed for aphrodisiac activity in traditional folklore, no scientific evidence is available. Therefore, we aimed to determine the effect of M.oleifera leaves extract on male sexual behaviors in animal model of sexual dysfunction. Moreover, the possible underlying mechanisms were also investigated. Approach: Male Wistar rats, weighing 200-250 g, had been orally given M.oleifera leaves extract at doses of 10, 50 and 250 mg kg-1 BW once daily at 30 min before the exposure to 12-h immobilization stress for 14 days. They were assessed male sexual behaviors including mounting, intromission and ejaculation numbers and latencies after single administration and every 7 days until the end of experiment. To further investigate the possible mechanisms of action, we also determined serum testosterone level of all rats at the end of experiment together with the determination of suppression effect of the plant extract on MAOB and PDE-5 activities. Results: The results showed that after single administration, rats subjected to M.oleifera extract at dose of 10 mg kg-1 BW significantly enhanced mounting number. When the treatment was prolonged to 7 days rats subjected to the low dose of extract showed the enhanced intromission number whereas rats subjected to high dose of extract showed the enhanced mounting number. Our data also showed no significant change in serum testosterone level. However, the extract could also suppress MAOB and PDE-5 activities. Taken all together, the extract could enhance male sexual desire and performance via the suppression of MAOB and PDE-5 activities. Conclusion: M.oleifera can be the potential sexual enhancer particularly for acute and short term application. However, further researches are necessary.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.17.24 2012/09/01 - 20:56

Problem statement: Phonological awareness is a major contributor to reading development. While the literature has primarily focused on the segmental aspect of phonology, suprasegmental information, namely prosody, has been largely underexplored in comparison. Approach: This review focuses on recent behavioral and neuroimaging studies on the development of prosody sensitivity during early childhood and the influence of prosody on reading processes. Results: Overall, the literature highlights the importance of prosodic information, not only during reading acquisition in children, but also during silent reading in skilled readers. This contribution is independent of segmental phonology, but may influence the development of phonological awareness. Conclusion: The current findings open the door to the development of new reading assessment tools that can allow determining whether pre-literacy students are at risk for reading development difficulties.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.10.16 2012/03/19 - 17:34

Problem statement: Diphenylhydantoin (phenytoin) is an antiepileptic drug that generates hyperplasia in some tissue by stimulating Epidermal Growth Factor (EGFR) and Platelet-Derived Growth Factor beta (PDGFR-β) receptors and by increasing serum levels of basic fibroblast growth factor (bFGF, FGF2 or FGF-β). Neural stem cells in the adult brain have been isolated from three regions: the Subventricular Zone (SVZ) lining the lateral wall of the lateral ventricles, the Subgranular Zone (SGZ) in the dentate gyrus at the hippocampus and the Subgranular Zone (SZC) lining between the hippocampus and the corpus callosum. Neural stem cells actively respond to bFGF, PDGFR-β or EGF by increasing their proliferation, survival and differentiation. The aim of this study was to evaluate the effect of phenytoin on proliferation and apoptosis in the three neurogenic niches in the adult brain. Approach: We orally administrated phenytoin with an oropharyngeal cannula for 30 days: 0 mg kg-1 (controls), 1, 5, 10, 50 and 100 mg kg-1. To label proliferative cells, three injections of 100 mg kg-1 of BrdU was administrated every 12 h. Immunohistochemistry against BrdU or Caspase-3 active were performed to determine the number of proliferative or apoptotic cells. Results: Our results showed that phenytoin induces proliferation in the SVZ and the SGZ in a dose-dependent manner. No statistically significant effects on cell proliferation in the SCZ neither in the apoptosis rate at the SVZ, SGZ and SCZ were found. Conclusion: These data indicate that phenytoin promotes a dose-dependent proliferation in the SVZ and SGZ of the adult brain. The clinical relevance of these findings remain to be elucidated.

http://www.thescipub.com/abstract/10.3844/amjnsp.2012.1.9 2012/03/07 - 11:07

Problem statement: Diphenylhydantoin (phenytoin) is an antiepileptic drug that generates hyperplasia in some tissue by stimulating Epidermal Growth Factor (EGFR) and Platelet-Derived Growth Factor beta (PDGFR-β) receptors and by increasing serum levels of basic fibroblast growth factor (bFGF, FGF2 or FGF-β). Neural stem cells in the adult brain have been isolated from three regions: the Subventricular Zone (SVZ) lining the lateral wall of the lateral ventricles, the Subgranular Zone (SGZ) in the dentate gyrus at the hippocampus and the Subgranular Zone (SZC) lining between the hippocampus and the corpus callosum. Neural stem cells actively respond to bFGF, PDGFR-β or EGF by increasing their proliferation, survival and differentiation. The aim of this study was to evaluate the effect of phenytoin on proliferation and apoptosis in the three neurogenic niches in the adult brain. Approach: We orally administrated phenytoin with an oropharyngeal cannula for 30 days: 0 mg kg-1 (controls), 1, 5, 10, 50 and 100 mg kg-1. To label proliferative cells, three injections of 100 mg kg-1 of BrdU was administrated every 12 h. Immunohistochemistry against BrdU or Caspase-3 active were performed to determine the number of proliferative or apoptotic cells. Results: Our results showed that phenytoin induces proliferation in the SVZ and the SGZ in a dose-dependent manner. No statistically significant effects on cell proliferation in the SCZ neither in the apoptosis rate at the SVZ, SGZ and SCZ were found. Conclusion: These data indicate that phenytoin promotes a dose-dependent proliferation in the SVZ and SGZ of the adult brain. The clinical relevance of these findings remain to be elucidated.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.70.78 2012/02/29 - 17:12

Problem statement: Aluminium is presents in many manufactured foods, medicines and is also added to drinking water for purification purposes. It has the potential to be neurotoxic in human and animals but its contribution in Alzhemer’s disease remains contradictory. Anxiety affects one-eighth of the total population world-wide and has become an important area of research interest in psychopharmacology. Approach: The present study was aimed at evaluating the effects that Aluminium chloride could have on anxiety-related Behaviour of Adult wistar Rats. A total of Ten (10) Adult wistar rats were used for this experiment. The wistar rats were divided into five groups: Group I was the control that received distil water, Group II received 475 mg Kg-1, Group III received 950 mg kg-1, Group IV received 1,425 mg kg-1 and Group V received 1,900 mg kg-1 through oral intubation for duration of Eight weeks. Elevated plus maze was used to assay for anxiety-related behaviour of the wistar rats. The wistar rats were placed at the junction of the four arms of the maze, facing a closed arm, allowed to freely explore the maze and their behavior was recorded simultaneously for 5 m by means of a video camera. Results: Wistar rats treated with Aluminium Chloride had, increased faecal boli, increased number of time crossing close arm entries and increased average time spent in close arms; but decreased time (lesser time) spent in the open arm of the maze when compared with the control group. This in turn implies that the Aluminium treated groups were more anxious than the control groups in exploration of their activities on the Elevated plus maze. Conclusion: It was concluded that Aluminium Chloride exposure has negative effects on anxiety-related behaviour of wistar rats as indicated by increased rate of anxiety in aluminium treated rats.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.65.69 2012/02/28 - 16:00

Problem statement: Motor Imagery (MI), which corresponds to an active process during which the representation of a specific action is internally reproduced into working memory without any motor output. It represents the result of conscious access to the content of a movement intention, which is usually performed unconsciously during movement preparation. Approach: This review study aims to provide information on the current research and main findings related to the potential therapeutic effects of motor imagery on stroke neurorehabilitation. Results: Several studies demonstrate that conscious motor imagery and unconscious motor preparation share common mechanisms and are functionally equivalent, improving recovery of motor skills in stroke patients. Conclusion: In conclusion, motor imagery, proved very useful and effective, with significant results in improvement of motor deficits in post stroke patients. Thus, it is recommended that further studies must be conducted to determine specific parameters such as number and weekly frequency, duration (minutes per session), type (visual or kinesthetic) and the appropriate moment to apply mental practice (phases recovery of pathology), in order to create specific protocols for each treatment phase.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.59.64 2012/02/13 - 17:29

Problem statement: Idiopathic Parkinson's Disease (PD) has being increasingly seen as a neuropsychiatric entity and no longer purely neurological, given the frequency and exuberance with which the psychiatric manifestations occurs. Approach: This review will focus on the epidemiology, clinical aspects, differential diagnosis with Alzheimer's Disease (AD) associated with parkinsonism, Dementia with Lewy Bodies (LBD), Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), Multiple System Atrophy (MSA), Vascular Parkinsonism and Normal Pressure Hydrocephalus (NPN), underlying mechanisms and treatment of dementia in PD. A literature review of the studies that investigated the dementia in PD was performed. Results: The dementia in PD has being increasingly recognized as a distinct nosological entity. Although specific etiologies for cognitive impairment remain unknown, a symptomatic treatment has been approved and strategies for early intervention are envisioned. Conclusion: Larger scale, placebo controlled clinical trials are needed to be explored in future studies to provide an evidence base to guide the management in dementia associated with PD.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.35.47 2012/02/13 - 17:29

Problem statement: The structural and functional neuroimaging have much to contribute to the cognitive neuroscience. Approach: We describe a radiological review of the major dementia syndromes and Mild Cognitive Impairment (MCI), included Alzheimer's disease, Lewy body dementia, Vascular dementia, Front temporal Lobar degeneration, Dementia associated with parkinsonism and other amnesic syndromes. Results: The different syndromes and diseases presenting with dementia have different patterns of brain perfusion abnormalities, it is possible to distinguish them with good specificity with neuroimaging. Conclusion: New imaging techniques carry the hope of revolutionizing the diagnosis of dementia so as to obtain a complete molecular, structural and metabolic characterization, which could be used to improve diagnosis and to stage each patient and follow disease progression and response to treatment. Structural and functional imaging modalities contribute to the diagnosis and understanding of the different dementias.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.48.58 2012/02/13 - 17:29

Problem statement: The visual analysis of Electroencephalogram (EEG) activity has shown useful as a complementary tool in Alzheimer Disease (AD diagnosis) when the diagnosis remains uncertain, in addition to be used in some clinical protocols. However, this analysis is subject to the inherent equipment imprecision, biological artifact, electrical records, and subjective physician interpretation of the visual analysis variation. The Artificial Neural Network (ANN) could be a helpful tool, appropriate to address problems such as prediction and pattern recognition. Approach: In this study, it was used a new class of ANN, namely the Paraconsistent Artificial Neural Network (PANN), which is capable of handling uncertain, inconsistent, and paracomplete information, for recognizing predetermined patterns of EEG activity and to assess its value as a possible complementary method for AD diagnosis. Thirty three AD patients and thirty four controls patients of EEG records were obtained during relaxed wakefulness. It was considered as normal patient pattern, the background EEG activity between 8.0 Hz and 12.0 Hz (with an average frequency of 10.0 Hz), allowing a range of 0.5 Hz. Results: The PANN was able to recognize waves that belonging to their respective bands of clinical use (theta, delta, alpha, and beta), leading to an agreement with the clinical diagnosis at 80% of sensitivity and at 73% of specificity. Conclusion: Supported by results, the PANN could be a promising tool to manipulate EEG analysis, bearing in mind the following considerations: the growing interest of specialists in EEG visual analysis and the ability of the PANN to deal in directly imprecise, inconsistent and paracomplete data, providing an interesting quantitative and qualitative analysis.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.17.27 2012/02/13 - 17:29

Problem statement: Amyotrophic Lateral Sclerosis (ALS) is a progressive and degenerative disease that affects the anterior horn motor neurons of the spinal cord and pyramidal tracts. In Brazil, there are few epidemiological data on this disease. Recently, some important findings have been reported, allowing a better understanding on the underlying processes of neuronal death, as well as the characteristics of this population. To discuss the clinical and functional profile of a convenience sample of patients with ALS in Rio de Janeiro and Neurology Department-Federal Fluminense University to compare the data with studies of other regions and countries. Approach: We used the Severity and Functional Ability Scale (SFAS) as a clinical and functional indicator for ALS. The modified El Escorial criteria were used to establish the diagnosis. The participants underwent five quarterly assessments during the study period. The research took place at two University Hospitals (Hospital Universitario Antonio Pedro-Universidade Federal Fluminense and Instituto de Neurologia Deolindo Couto-Universidade Federal do Rio de Janeiro) from March 2007 to December 2009. Results: Of the 98 recruited subjects, only 24 have completed all phases of the study. The average age was 52.7±4.1 years. The time between the onset of first symptoms and seeking care services was 11.6±12.:4 months. The time between the first symptoms and the diagnosis was 20.5±8.4 months. Muscle weakness was identified as the initial symptom in most cases. Patients had impaired muscle strength, speech, swallowing, respiratory function and severity stages of SFAS. The disease had different forms of initial presentation (impaired speech, limbs strength, respiratory function or swallowing), time to progression and clinical characteristics in our population. Conclusion: The knowledge on the individual clinical evolution in ALS is of paramount importance for the healthcare team to provide a correct treatment during the decline of the disease and formulate theoretical and conceptual issues, aiming at solving problems in clinical practice.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.28.34 2012/02/13 - 17:29

Problem statement: Repetitive Transcranial Magnetic Stimulation (rTMS) is a noninvasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Dystonia is characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Approach: Consequently, more advanced non-invasive therapeutic methods were required. A possible method to modulate brain activity and potentially viable for use in clinical practice was rTMS. We focus on the basic foundation of rTMS, the effects of rTMS on neuroplasticity and sensorimotor integration and the experimental advances of rTMS that may become a viable clinical application to treat dystonia. Results: The findings showed that rTMS can improve some symptoms associated with dystonia and might be useful for promoting cortical plasticity in dystonic patients. These changes were transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has shown itself to be, potentially, a modulator of sensorimotor integration and neuroplasticity. Conclusion/Recommendations: Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. We recommend further studies to clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by their ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.5.16 2012/02/13 - 17:29

Problem statement: Peripheral neuropathy due to diabetes has been studied for several decades. Until recently, we associate the involvement of peripheral nerves with an inappropriate glycemic control in the most advanced stages of the disease. Currently, it is considered that the onset of the neural injury can occur in the initial phase of this metabolic abnormality, during the period of glucose intolerance. Approach: The clinical aspects of the sensory neuropathy associated to the impaired glucose tolerance were analyzed in 35 Brazilian patients. All patients met the American Diabetes Association (ADA) and the World Health Organization (WHO) criteria for glucose intolerance. Results: We studied 20 male and 15 female, with a mean age of 62.5, ranging from 30-83 years. A distal symmetrical lower limb involvement with positive (neuropathic pain) and/or negative (reduced temperature and pinprick sensations) symptoms and clinical signs of autonomic neuropathy were seen in most patients. The glycemic levels were not related to the severity of the symptoms or to the presence of any specific symptom. Conclusion: The Impaired Glucose Tolerance (IGT) neuropathy can be included in the chronic axonal polyneuropathy and usually the patients suffer from chronic pain and disability before the diagnosis. The determination of the prevalence of symptoms is essential to recognize this disease. The early diagnosis and the aggressive treatment can be crucial for the control, development and progression of the small fiber neuropathy in glucose intolerant patients.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.1.4 2012/02/13 - 17:29

Problem statement: Motor Imagery (MI), which corresponds to an active process during which the representation of a specific action is internally reproduced into working memory without any motor output. It represents the result of conscious access to the content of a movement intention, which is usually performed unconsciously during movement preparation. Approach: This review study aims to provide information on the current research and main findings related to the potential therapeutic effects of motor imagery on stroke neurorehabilitation. Results: Several studies demonstrate that conscious motor imagery and unconscious motor preparation share common mechanisms and are functionally equivalent, improving recovery of motor skills in stroke patients. Conclusion: In conclusion, motor imagery, proved very useful and effective, with significant results in improvement of motor deficits in post stroke patients. Thus, it is recommended that further studies must be conducted to determine specific parameters such as number and weekly frequency, duration (minutes per session), type (visual or kinesthetic) and the appropriate moment to apply mental practice (phases recovery of pathology), in order to create specific protocols for each treatment phase.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.96.101 2012/01/22 - 03:49

Problem statement: Idiopathic Parkinson’s Disease (PD) has being increasingly seen as a neuropsychiatric entity and no longer purely neurological, given the frequency and exuberance with which the psychiatric manifestations occurs. Approach: This review will focus on the epidemiology, clinical aspects, differential diagnosis with Alzheimer’s Disease (AD) associated with parkinsonism, Dementia with Lewy Bodies (LBD), Progressive Supranuclear Palsy (PSP), Corticobasal Degeneration (CBD), Multiple System Atrophy (MSA), Vascular Parkinsonism and normal pressure hydrocephalus (NPN), underlying mechanisms and treatment of dementia in PD. A literature review of the studies that investigated the dementia in PD was performed. Results: The dementia in PD has being increasingly recognized as a distinct nosological entity. Although specific etiologies for cognitive impairment remain unknown, a symptomatic treatment has been approved and strategies for early intervention are envisioned. Conclusion: Larger scale, placebo controlled clinical trials are needed to be explored in future studies to provide an evidence base to guide the management in dementia associated with PD.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.72.84 2011/11/26 - 14:20

Problem statement: The structural and functional neuroimaging have much to contribute to the cognitive neuroscience. Approach: We describe a radiological review of the major dementia syndromes and Mild Cognitive Impairment (MCI), included Alzheimer's disease, Lewy body dementia, Vascular dementia, Front temporal Lobar degeneration, Dementia associated with parkinsonism and other amnesic syndromes. Results: The different syndromes and diseases presenting with dementia have different patterns of brain perfusion abnormalities, it is possible to distinguish them with good specificity with neuroimaging. Conclusion: New imaging techniques carry the hope of revolutionizing the diagnosis of dementia so as to obtain a complete molecular, structural and metabolic characterization, which could be used to improve diagnosis and to stage each patient and follow disease progression and response to treatment. Structural and functional imaging modalities contribute to the diagnosis and understanding of the different dementias.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.85.95 2011/11/26 - 14:20

Problem statement: The visual analysis of Electroencephalogram (EEG) activity has shown useful as a complementary tool in Alzheimer Disease (AD diagnosis) when the diagnosis remains uncertain, in addition to be used in some clinical protocols. However, this analysis is subject to the inherent equipment imprecision, biological artifact, electrical records, and subjective physician interpretation of the visual analysis variation. The Artificial Neural Network (ANN) could be a helpful tool, appropriate to address problems such as prediction and pattern recognition. Approach: In this study, it was used a new class of ANN, namely the Paraconsistent Artificial Neural Network (PANN), which is capable of handling uncertain, inconsistent, and paracomplete information, for recognizing predetermined patterns of EEG activity and to assess its value as a possible complementary method for AD diagnosis. Thirty three AD patients and thirty four controls patients of EEG records were obtained during relaxed wakefulness. It was considered as normal patient pattern, the background EEG activity between 8.0 Hz and 12.0 Hz (with an average frequency of 10.0 Hz), allowing a range of 0.5 Hz. Results: The PANN was able to recognize waves that belonging to their respective bands of clinical use (theta, delta, alpha, and beta), leading to an agreement with the clinical diagnosis at 80% of sensitivity and at 73% of specificity. Conclusion: Supported by results, the PANN could be a promising tool to manipulate EEG analysis, bearing in mind the following considerations: the growing interest of specialists in EEG visual analysis and the ability of the PANN to deal in directly imprecise, inconsistent and paracomplete data, providing an interesting quantitative and qualitative analysis.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.54.64 2011/10/06 - 12:49

Problem statement: Amyotrophic Lateral Sclerosis (ALS) is a progressive and degenerative disease that affects the anterior horn motor neurons of the spinal cord and pyramidal tracts. In Brazil, there are few epidemiological data on this disease. Recently, some important findings have been reported, allowing a better understanding on the underlying processes of neuronal death, as well as the characteristics of this population. To discuss the clinical and functional profile of a convenience sample of patients with ALS in Rio de Janeiro and Neurology Department-Federal Fluminense University to compare the data with studies of other regions and countries. Approach: We used the Severity and Functional Ability Scale (SFAS) as a clinical and functional indicator for ALS. The modified El Escorial criteria were used to establish the diagnosis. The participants underwent five quarterly assessments during the study period. The research took place at two University Hospitals (Hospital Universitario Antonio Pedro-Universidade Federal Fluminense and Instituto de Neurologia Deolindo Couto-Universidade Federal do Rio de Janeiro) from March 2007 to December 2009. Results: Of the 98 recruited subjects, only 24 have completed all phases of the study. The average age was 52.7±4.1 years. The time between the onset of first symptoms and seeking care services was 11.6±12.:4 months. The time between the first symptoms and the diagnosis was 20.5±8.4 months. Muscle weakness was identified as the initial symptom in most cases. Patients had impaired muscle strength, speech, swallowing, respiratory function and severity stages of SFAS. The disease had different forms of initial presentation (impaired speech, limbs strength, respiratory function or swallowing), time to progression and clinical characteristics in our population. Conclusion: The knowledge on the individual clinical evolution in ALS is of paramount importance for the healthcare team to provide a correct treatment during the decline of the disease and formulate theoretical and conceptual issues, aiming at solving problems in clinical practice.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.65.71 2011/10/06 - 12:49

Problem statement: Repetitive Transcranial Magnetic Stimulation (rTMS) is a noninvasive procedure whereby a pulsed magnetic field stimulates electrical activity in the brain. Dystonia is characterized by several disabling symptoms for which effective, mechanism-based treatments remain elusive. Approach: Consequently, more advanced non-invasive therapeutic methods were required. A possible method to modulate brain activity and potentially viable for use in clinical practice was rTMS. We focus on the basic foundation of rTMS, the effects of rTMS on neuroplasticity and sensorimotor integration and the experimental advances of rTMS that may become a viable clinical application to treat dystonia. Results: The findings showed that rTMS can improve some symptoms associated with dystonia and might be useful for promoting cortical plasticity in dystonic patients. These changes were transient and it is premature to propose these applications as realistic therapeutic options, even though the rTMS technique has shown itself to be, potentially, a modulator of sensorimotor integration and neuroplasticity. Conclusion/Recommendations: Functional imaging of the region of interest could highlight the capacity of rTMS to bring about plastic changes of the cortical circuitry and hint at future novel clinical interventions. We recommend further studies to clearly determine the role of rTMS in the treatment of these conditions. Finally, we must remember that however exciting the neurobiological mechanisms might be, the clinical usefulness of rTMS will be determined by their ability to provide patients with neurological and psychiatric disorders with safe, long-lasting and substantial improvements in quality of life.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.42.53 2011/08/14 - 16:34

Problem statement: Peripheral neuropathy due to diabetes has been studied for several decades. Until recently, we associate the involvement of peripheral nerves with an inappropriate glycemic control in the most advanced stages of the disease. Currently, it is considered that the onset of the neural injury can occur in the initial phase of this metabolic abnormality, during the period of glucose intolerance. Approach: The clinical aspects of the sensory neuropathy associated to the impaired glucose tolerance were analyzed in 35 Brazilian patients. All patients met the American Diabetes Association (ADA) and the World Health Organization (WHO) criteria for glucose intolerance. Results: We studied 20 male and 15 female, with a mean age of 62.5, ranging from 30-83 years. A distal symmetrical lower limb involvement with positive (neuropathic pain) and/or negative (reduced temperature and pinprick sensations) symptoms and clinical signs of autonomic neuropathy were seen in most patients. The glycemic levels were not related to the severity of the symptoms or to the presence of any specific symptom. Conclusion: The Impaired Glucose Tolerance (IGT) neuropathy can be included in the chronic axonal polyneuropathy and usually the patients suffer from chronic pain and disability before the diagnosis. The determination of the prevalence of symptoms is essential to recognize this disease. The early diagnosis and the aggressive treatment can be crucial for the control, development and progression of the small fiber neuropathy in glucose intolerant patients.

http://www.thescipub.com/abstract/10.3844/amjnsp.2011.38.41 2011/08/14 - 16:34

Problem statement: Research has suggested that examining attentional demands during
functional tasks is an emergent area of study. Increased arousal may represent an attentional demand,
resulting in impaired motor functioning in tasks that require fast reaction and movement times.
Approach: This study examined the effects of a non-specific stressor and the resultant physiological
arousal on upper extremity functional measures of motor performance. Forty-four young adult
participants (X age = 20.6) were randomly assigned to either a stress/arousal group or non-stress
control group. Arousal was altered through the use of the Stroop Color Word Task and mental
subtraction tasks. Results: Paired-sample analyses revealed significant differences (p<.037) from pre
to post test for measures of reaction time in the stress group. No significant differences were seen for
measures of movement time (p<.095) in the stress group. Conclusion: These results suggest that
increased levels of physiological arousal may alter reaction time, movement time and resultant motor
functioning in healthy young adults. This increase in physiological arousal may be the result of nonspecific
external stressors and have significant implications for movement production accuracy in
multiple populations, including older adults. Further research examining this effect in older adults is
ongoing.

http://www.thescipub.com/abstract/10.3844/amjnsp.2010.28.33 2011/04/03 - 08:31

Problem statement: The definition of "symbolic species" used by Terrence W. Deacon
means more complete the process of monitoring the encounter between semiotics and cognitive
sciences neurosemiotics better defined. Approach: The mechanism of the symbolic threshold means
that it is put in place an approach to reality no longer seen as a representative of simple association, but
under a restructuring or a recombination, at least relatively stable, a number of different elements in a
hierarchical plan. Possible will be a channel for research that is based on the theoretical model called
"symbolic" and use the model interactive / cognitive develop through which different forms of
language, communication and supports the expression and actions of each of us. From the
neurobiological point of view, with regard to neuronal function, several theories are based on brain
function as a binder with extreme plasticity, consistent with fragments of information to higher levels
of the brain are organized and interact in order to acquire meaning. These transactions are done
through organizing maps consist of groups of neurons, synapses and neurotransmitters, continuous
regeneration to form categories of objects and events to recognize. Results: The most effective in
building a map of the difference of a traditional information technology, borrowed from the language
suggested by our mind, are much more spontaneous and direct .The study showed the effectiveness of
this tool as the construction of knowledge of the inexhaustible capacity of the mind during laboratory
work at the Degree of Education, University of Salerno (Italy), compared to affected users mainly
adopt systems, strategies and possible interventions for teaching in kindergartens and adolescence.
Conclusion: Applicability of the questionnaires were administered in teaching and scientific mind
map. The consequences of the administration of the questionnaire has far exceeded expectations and
led the students, the motivation to carry out projects to promote knowledge of the fundamentals of
experience in various fields and disciplines, through a system that is considered usable, functional,
from early childhood, particularly for people with disabilities.

http://www.thescipub.com/abstract/10.3844/amjnsp.2010.34.37 2011/04/03 - 08:31

Problem statement: Developmental Dyslexia (DD) or Reading Disability (RD) that was part of a larger heterogeneous group of learning disorders and characterized by unexpected problems in academic performance, despite average intelligence. Approach: Current opinions on the biological basis of dyslexia pointed to problems with phonological processing deficits with resulting poor phonemic awareness. Though there was much support for this hypothesis in the scientific literature, there remained an ongoing debate as to whether the core deficit was in fact a more general information processing problem that involves phonological awareness, phonological short-term memory, phonological re/de-coding Rapid Automatized Naming (RAN). Results: Also double deficit hypothesis proposed that the dyslexic children impaired in word-identification accuracy or exhibiting slowly word decoding profile. Conclusion/Recommendations: The aim of this review was to present some of the most exciting researches on DD in the domains of phonological deficit theory that those will help future studies to follow.

http://www.thescipub.com/abstract/10.3844/ajnsp.2010.1.12 2011/01/11 - 03:46

Problem statement: The aphasia is one of human language and action related brain associative diseases. The mechanisms of the diseases and the brain association are still unclear. In this study, we proposed our models of the neuronal signal processes, in a view of BioInforPhysics, to understand the mechanisms. Approach: Our models are based on today’s solidest Electromagnetic Fields (EMF) theoretic fundamentals: Maxwell EMF equations, Poynting theorem and vector, Lorentz law and other well known EMF principles, as well as published biomedical data. Methods cover the signal collections and analysis, correlations and synthesis; the correlations include functions derivatives as well as the functions. Results: (a) The signals have three attributes (or elements): the information, the energies and the matters; (b) the fields intensities are the Information Intensities (II), products of the II are the Information Response Intensities (IRI) of energies expressions, products of the II and the matters (charges) are the IRI of forces expressions; (c) the information can produce the new information; (d) the energies can carry or (and) transmit the information; (e) the matters (charges) can store and produce the information. The EMF information is not conservative in biological fluids because of the charges or the attenuation of the II. Our models in this study are the signals oriented and combine the information, the energies and the matters. Conclusion: Approximately, neurons work like microcomputers; the synapses work like signal input interfaces and perform the signal collections and analysis; the neuronal bodies work like microprocessors and execute the signal correlations and synthesis in parallel; DNA, RNA, proteins and other cellular components work like memories or circuits; the axons work like signal output interfaces and segregate the signal stream to other neurons. The all processes in the neurons and the nervous system are automatically completed by the natural laws. We intended to approach the natural laws with our models.

http://www.thescipub.com/abstract/10.3844/ajnsp.2010.13.20 2011/01/11 - 03:46

Problem statement: Oxidative stress is a major factor implicated in the degeneration of cholinergic neurons in Alzheimer’s Disease (AD). Several reports have indicated that antioxidant intake is beneficial to delay or inhibit the progression of this disease. Presently, Acetylcholinesterase (AChE) inhibitors are the mainstay of therapy for AD. Quercetin, one of the flavonoids in fruits and vegetables, has a powerful antioxidant activity both in vitro and in vivo. However, the potential of quercetin as Acetylcholinesterase (AChE) inhibitors, an important aspect for neuroprotection, has not been properly investigated. Approach: This study was designed to evaluate the anti-cholinesterase activity and improves cognitive function of quercetin liposomes via nasal administration in a rat AF64A injection model of AD. Male Wistar rats were pretreated with quercetin liposomes, containing 0.5 mg of quercetin in 20 μL via intranasal route once daily continually for 3 weeks. Learning and memory was evaluated using the Morris water maze test at 7 days after the lesioning and then the rats were sacrificed for determining the contents of Acetylcholinesterase (AChE), the activities of Superoxide Dismutase (SOD), Glutathione Peroxidase (GPx) and Malondialdehide (MDA), a lipid peroxidation product in the hippocampus. Results: AF64A with nasal administration of free liposomes showed the loss of cognitive performance in Morris water maze test, increase in the markers of oxidative damage (MDA, SOD and GPX) and the AChE activity in the hippocampus. However, AF64A with nasal administration of quercetin liposomes reversed all the parameters significantly. Conclusion: Our studies demonstrated that quercetin liposomes via nasal administration may have a therapeutic importance in the clinical management of Alzheimer’s disease.

http://www.thescipub.com/abstract/10.3844/ajnsp.2010.21.27 2011/01/11 - 03:46