Social communication uses verbal and nonverbal language. We examined the degree of trust and brain activity when verbal and facial expressions are incongruent. Fourteen healthy volunteers viewed photographs of 8 people with pleasant (smile) or unpleasant expressions (disgust) alone or combined with a verbal [positive/negative] expression. As an index for degree of trust, subjects were asked to offer a donation when told that the person in the photograph was troubled financially. Positive emotions and degree of trust were evaluated using the Visual Analogue Scale (VAS). Event-related potentials (ERPs) were obtained at 170–240 ms after viewing the photographs. Brain activity during incongruent conditions was localized using standardized Low Resolution Brain Electromagnetic Tomography (sLORETA). VAS scores for positive × smile condition were significantly higher than those for the other conditions (p<0.05). The donation offered was significantly lower for incongruence between verbal and facial expressions, particularly for negative × smile condition. EEG showed more activity in the parietal lobe with incongruent than with congruent conditions. Incongruence [negative × smile] elicited the least positive emotion, degree of trust, and amount of offer. Our results indicate that incongruent sensory information increased activity in the parietal lobe, which may be a basis of mentalizing.
Background.Muscle vibration has been shown to increase the corticospinal excitability assessed by transcranial magnetic stimulation (TMS) and to change voluntary force production in healthy subjects.Objectives.To evaluate the effect of vibration on corticospinal excitability using TMS and on maximal motor output using maximal voluntary contraction (MVC) in individuals with chronic hemiparesis.Methodology.Nineteen hemiparetic and 17 healthy control subjects participated in this study. Motor evoked potentials (MEPs) and MVC during lateral pinch grip were recorded at first dorsal interosseous muscle in a single session before, during, and after one-minute trials of 80 Hz vibration of the thenar eminence.Results.In hemiparetic subjects, vibration increased MEP amplitudes to a level comparable to that of control subjects and triggered a MEP response in 4 of 7 patients who did not have a MEP at rest. Also, vibration increased the maximal rate of force production (dF/dtmax) in both control and hemiparetic subjects but it did not increase MVC.Conclusion.Motor response generated with a descending cortical drive in chronic hemiparetic subjects can be increased during vibration. Vibration could be used when additional input is needed to reveal motor responses and to increase rate of force generation.
Introduction. Calabash chalk contains heavy metals, and this lead to this study on the effect of this chalk on the behavior and the histomorphology of the cerebral cortex of gestating rats. Material & Methods. 24 female rats were equally divided into 4 groups and were mated at preostrous with the males. The day after mating was designated as day 1 of gestation. On gestation days 7–20, groups 1, 2, 3, and 4 animals were treated with 1 mL of distilled water, and 1 mL (200 mg/kg), 2 mL (400 mg/kg), and 3 mL (600 mg/kg) of calabash chalk suspension, respectively. On pregnancy day 21, behavioral tests using the open field and the light/dark mazes were carried out and the animals subsequently euthanized and their brains were routinely processed. Results. There was no difference in ambulatory activities, but group 4 animals had more (P<0.05) transition frequency and were more averse to the dark in the light and dark field, while sections of the cerebral cortex showed a higher (P<0.05) cellular population, hypertrophied pyramidal cells, and vacuolations in the treatment groups. Conclusion. Calabash chalk may have anxiolytic effect especially at high dose in the light and dark field but not in the open field and can stimulate maternal cerebral cortical cellular changes.
The molecular chaperone heat shock protein 90 alpha (Hsp90α) has been recognized in various tumours including glioma. This pilot study using a proteomic approach analyses the downstream effects of Hsp90 inhibition using 17-allylamino-17-demethoxygeldanamycin (17AAG) and a short hairpin RNA (shRNA) oligonucleotide targetinghsp90α(shhsp90α) in the U87-MG glioma cell line. Preliminary data coupled with bioinformatic analysis identified several known and unknown Hsp90 client proteins that demonstrated a change in their protein expression after Hsp90 inhibition, signifying an alteration in the canonical pathways of cell cycle progression, apoptosis, cell invasion, angiogenesis, and metastasis. Members of the glycolysis pathway were upregulated, demonstrating increased dependency on glycolysis for energy source by the treated glioma cells. Upregulated proteins also include Hsp70 and members of its family such as Hsp27 and gp96, thereby suggesting the role of Hsp90 co-chaperones in compensating for Hsp90 function after Hsp90 inhibition. Considering Hsp70’s role in antiapoptosis, it was postulated that a combination therapy involving a multitarget approach could be carried out. Consequently inhibition of both Hsp90 and Hsp70 in U87-MG glioma cells resulted in 60% cell death indicating the importance of combination therapy for glioma therapeutics.
As the emergence of cancer is most frequent in proliferating tissues, replication errors are considered to be at the base of this disease. This review concentrates mainly on two neural cancers, neuroblastoma and glioma, with completely different backgrounds that are well documented with respect to their ontogeny. Although clinical data on other cancers of the nervous system are available, usually little can be said about their origins. Neuroblastoma is initiated in the embryo at a moment when the nervous system (NS) is in full expansion and occasionally genomic damage can lead to neoplasia. Glioma, to the contrary, occurs in the adult brain supposed to be mostly in a postmitotic state. According to current consensus, neural stem cells located in the subventricular zone (SVZ) in the adult are thought to accumulate enough genomic mutations to diverge on a carcinogenic course leading to diverse forms of glioma. After weighing the pros and cons of this current hypothesis in this review, it will be argued that this may be improbable, yielding to the original old concept of glial origin of glioma.
The objectives were to evaluate alterations in ischemic rat pups, from dams administered with curcumin (25 and 50 mg/kg). Ten-day-old male pups were subjected or not (SO) to brain ischemia and reperfusion, for 1, 7, and 14 days (this last group was submitted to behavioral evaluation). After that, pups were euthanized for determinations of striatal DA and DOPAC in SO, ischemic from untreated (ICUD) or curcumin treated (ICTD) dams, as well as hippocampal immunohistochemistry assays for iNOS and COX-2 and cresyl violet staining. At the 14th postischemia day, the ICUD group showed increased locomotor activity and rearing behavior, which were reversed in ICTD animals. ICUD pups presented decreased striatal DA and DOPAC levels, relatively to SO, mainly at the 1st postischemia day, but also at the 7th and 14th days which were partially reversed in ICTD pups. A greater number of viable neurons were observed in ICTD, as related to the ICUD group. Ischemia increased iNOS and COX-2 expressions, in CA1 and CA3 areas, at the 1st, 7th, and 14th postischemia days, and these effects were minimized in ICTD pups. In conclusion, the prenatal curcumin treatment was shown to be neuroprotective where the drug anti-inflammatory and antioxidant effects probably play a role.
It has been suggested that the left temporal pole (Brodmann area 38 (BA38)) participates in diverse language functions, including semantic processing, speech comprehension, and naming. Utilizing the activation likelihood estimation (ALE), a meta-analytic connectivity study was conducted to further our understanding on the role of BA38 in language. Departing from the BrainMap functional database, 11 papers corresponding to 12 paradigms including 201 participants were selected. Initially, P<0.01 was employed as the significance level, resulting in the presence of four different activation clusters. However, when the significance level was lowered to P<0.05, sixteen activation clusters appeared, including classical language areas such as Broca’s and Wernicke’s areas. It was concluded that (1) this meta-analytic connectivity study suggests the presence of two major connection circuits involving BA38; one is related to language, while the other may be involved in visuospatial and integrative audiovisual functions. Furthermore, (2) BA38 also contributes to various brain networks supporting linguistic processes related not only to language comprehension but also to language production.
Mefloquine and Artequin are two effective antimalarial drugs currently in use in the treatment of uncomplicated malaria. This study was to investigate the hippocampal glial degenerative potentials of these drugs in adult Wistar rats. Forty-nine adult Wistar rats weighing 200 g were divided into groups 1–7. Group 1 served as the control that received distilled water, while groups 2–7 received oral doses of 0.86/1.07 mg/kg, 1.71/2.14 mg/kg, and 3.24/4.28 mg/kg of Artequin and 1.07 mg/kg, 2.14 mg/kg, and 4.28 mg/kg of Mefloquine. The treatment lasted for three days, and on day 4 the animals were sacrificed. Their hippocampi were preserved in neutral formal saline and processed by silver impregnation method. The histomorphology of the hippocampal sections of rats in the groups treated with 2.14 mg/kg and 4.28 mg/kg of Mefloquine and 0.86/1.07 mg/kg, 1.71/2.14 mg/kg, and 3.24/4.28 mg/kg of Artequin showed large and dense populations of astrocytes and astrocytes’ processes, with either loss or reduction in the population of oligodendrocytes. There was also loss in the population of pyramidal neurons all compared with the control group. In conclusion, Mefloquine and Artequin administration induced dose-dependent reactive astrocytes and astrocytes’ processes formation in the hippocampus. This may impair the uptake of neurotransmitter and alter neuronal environment thus altering the hippocampal function.
This paper reports the discovery of a geometrical algorithm that provides a coherent step by step mechanical account of the structure of the nervous system, including the vertebrate brain, the spinal cord, the vertebral column, and the spinal nerves. The morphology of these organs and the observed steps of neural development are well described, consequent of centuries of study. But morphogenesis, the origin and cause of these forms, has not been studied since the last half of the nineteenth century. Neurology does not teach how the brain gained its shape, nor have any causative theories of brain formation been published in recent times. This paper proposes a hypothetical construction based on the discovery of a simple algorithm which generates topologically the form of the brain, the spinal cord, and the vertebral column by the deformation of a gridded segmented sphere by the inversion of its surface. The hypothetical model is in close analogy with nature: the blastula is a segmented gridded sphere which results from the subdivision of the egg. The first step of embryogenesis is gastrulation, where blastula is pressed to enter its own interior, pulling the surface inside out, forming the embryo.
