Effects of beta-alanine supplementation on brain homocarnosine/carnosine signal and cognitive function: an exploratory study

Objectives: Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2). Methods: In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen trained male cyclists completed four 20-Km cycling time trials (two pre supplementation and two post supplementation), with a battery of cognitive function tests (Stroop test, Sternberg paradigm, Rapid Visual Information Processing task) being performed before and after exercise on each occasion. Results: In Study 1, there were no within-group effects of beta-alanine supplementation on brain homocarnosine/carnosine signal in either vegetarians (p = 0.99) or omnivores (p = 0.27); nor was there any effect when data from both groups were pooled (p = 0.19). Similarly, there was no group by time interaction for brain homocarnosine/carnosine signal (p = 0.27). In study 2, exercise improved cognitive function across all tests (P0.05) of beta-alanine supplementation on response times or accuracy for the Stroop test, Sternberg paradigm or RVIP task at rest or after exercise. Conclusion: 28 d of beta-alanine supplementation at 6.4g d-1 appeared not to influence brain homocarnosine/ carnosine signal in either omnivores or vegetarians; nor did it influence cognitive function before or after exercise in trained cyclists

Global and regional brain metabolic scaling and its functional consequences

Background: Information processing in the brain requires large amounts of metabolic energy, the spatial distribution of which is highly heterogeneous reflecting complex activity patterns in the mammalian brain. Results: Here, it is found based on empirical data that, despite this heterogeneity, the volume-specific cerebral glucose metabolic rate of many different brain structures scales with brain volume with almost the same exponent around -0.15. The exception is white matter, the metabolism of which seems to scale with a standard specific exponent -1/4. The scaling exponents for the total oxygen and glucose consumptions in the brain in relation to its volume are identical and equal to $0.86\pm 0.03$, which is significantly larger than the exponents 3/4 and 2/3 suggested for whole body basal metabolism on body mass. Conclusions: These findings show explicitly that in mammals (i) volume-specific scaling exponents of the cerebral energy expenditure in different brain parts are approximately constant (except brain stem structures), and (ii) the total cerebral metabolic exponent against brain volume is greater than the much-cited Kleiber's 3/4 exponent. The neurophysiological factors that might account for the regional uniformity of the exponents and for the excessive scaling of the total brain metabolism are discussed, along with the relationship between brain metabolic scaling and computation.Comment: Brain metabolism scales with its mass well above 3/4 exponen

Cellular Scaling Rules of Insectivore Brains

Insectivores represent extremes in mammalian body size and brain size, retaining various “primitive” morphological characteristics, and some species of Insectivora are thought to share similarities with small-bodied ancestral eutherians. This raises the possibility that insectivore brains differ from other taxa, including rodents and primates, in cellular scaling properties. Here we examine the cellular scaling rules for insectivore brains and demonstrate that insectivore scaling rules overlap somewhat with those for rodents and primates such that the insectivore cortex shares scaling rules with rodents (increasing faster in size than in numbers of neurons), but the insectivore cerebellum shares scaling rules with primates (increasing isometrically). Brain structures pooled as “remaining areas” appear to scale similarly across all three mammalian orders with respect to numbers of neurons, and the numbers of non-neurons appear to scale similarly across all brain structures for all three orders. Therefore, common scaling rules exist, to different extents, between insectivore, rodent, and primate brain regions, and it is hypothesized that insectivores represent the common aspects of each order. The olfactory bulbs of insectivores, however, offer a noteworthy exception in that neuronal density increases linearly with increasing structure mass. This implies that the average neuronal cell size decreases with increasing olfactory bulb mass in order to accommodate greater neuronal density, and represents the first documentation of a brain structure gaining neurons at a greater rate than mass. This might allow insectivore brains to concentrate more neurons within the olfactory bulbs without a prohibitively large and metabolically costly increase in structure mass

A framework for the first‑person internal sensation of visual perception in mammals and a comparable circuitry for olfactory perception in Drosophila

Perception is a first-person internal sensation induced within the nervous system at the time of arrival of sensory stimuli from objects in the environment. Lack of access to the first-person properties has limited viewing perception as an emergent property and it is currently being studied using third-person observed findings from various levels. One feasible approach to understand its mechanism is to build a hypothesis for the specific conditions and required circuit features of the nodal points where the mechanistic operation of perception take place for one type of sensation in one species and to verify it for the presence of comparable circuit properties for perceiving a different sensation in a different species. The present work explains visual perception in mammalian nervous system from a first-person frame of reference and provides explanations for the homogeneity of perception of visual stimuli above flicker fusion frequency, the perception of objects at locations different from their actual position, the smooth pursuit and saccadic eye movements, the perception of object borders, and perception of pressure phosphenes. Using results from temporal resolution studies and the known details of visual cortical circuitry, explanations are provided for (a) the perception of rapidly changing visual stimuli, (b) how the perception of objects occurs in the correct orientation even though, according to the third-person view, activity from the visual stimulus reaches the cortices in an inverted manner and (c) the functional significance of well-conserved columnar organization of the visual cortex. A comparable circuitry detected in a different nervous system in a remote species-the olfactory circuitry of the fruit fly Drosophila melanogaster-provides an opportunity to explore circuit functions using genetic manipulations, which, along with high-resolution microscopic techniques and lipid membrane interaction studies, will be able to verify the structure-function details of the presented mechanism of perception

Nitric oxide release using natural rubber latex as matrix

Nitric oxide (NO) is a diffusible messenger that has been involved in numerous physiological processes ranging from vasodilatation and antimicrobial properties to wound healing. The beneficial effects can be attributed to the role NO plays in angiogenesis, inflammation and tissue remodeling. In the present work, a polymeric device for the sustained site specific delivery of nitric oxide using a latex rubber matrix from Hevea brasiliensis which encapsulates the spin trap iron(II)- diethyldithiocarbamate complex (FeDETC) was developed. The release profiles of NO from latex rubber matrix were studied and stability studies were carried out. Electron Paramagnetic Resonance (EPR) signal of NO was detected in the membrane exposed to ambient atmosphere at room temperature (25 °C) even after 350 hours. FTIR spectroscopy data indicated that NO-FeDETC retained its structural and spectroscopic properties upon encapsulation in the latex matrix. The NO delivery system developed in this work as a membrane, presented high stability.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)UNESP Faculdade de Ciências e Letras de Assis Departamento de Ciências BiológicasUniversidade Sagrado CoraçãoUSP Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto Departamento de Física e MatemáticaUniversidade Federal de Itajubá Departamento de Física e QuímicaUNESP Faculdade de Ciências Departamento de FísicaUNESP Faculdade de Ciências e Letras de Assis Departamento de Ciências BiológicasUNESP Faculdade de Ciências Departamento de Físic

Co-evolution of cerebral and cerebellar expansion in cetaceans.

Cetaceans possess brains that rank among the largest to have ever evolved, either in terms of absolute mass or relative to body size. Cetaceans have evolved these huge brains under relatively unique environmental conditions, making them a fascinating case study to investigate the constraints and selection pressures that shape how brains evolve. Indeed, cetaceans have some unusual neuroanatomical features, including a thin but highly folded cerebrum with low cortical neuron density, as well as many structural adaptations associated with acoustic communication. Previous reports also suggest that at least some cetaceans have an expanded cerebellum, a brain structure with wide-ranging functions in adaptive filtering of sensory information, the control of motor actions, and cognition. Here, we report that, relative to the size of the rest of the brain, both the cerebrum and cerebellum are dramatically enlarged in cetaceans and show evidence of co-evolution, a pattern of brain evolution that is convergent with primates. However, we also highlight several branches where cortico-cerebellar co-evolution may be partially decoupled, suggesting these structures can respond to independent selection pressures. Across cetaceans, we find no evidence of a simple linear relationship between either cerebrum and cerebellum size and the complexity of social ecology or acoustic communication, but do find evidence that their expansion may be associated with dietary breadth. In addition, our results suggest that major increases in both cerebrum and cerebellum size occurred early in cetacean evolution, prior to the origin of the major extant clades, and predate the evolution of echolocation

Self-assembled gold nanoparticles and amphiphile peptides: a colorimetric probe for copper(ii) ion detection

Morphological, spectroscopic and scattering studies of the self-assembly and aggregation process of hybrids containing gold nanoparticles (AuNPs) and the amyloid peptides [RF]4 and P[RF]4 (where R = arginine; F = phenylalanine; P = proline) in aqueous solution were performed. Two methodologies were tested for the AuNP nucleation, using sodium borohydride (NaBH4) or epigallocatechin gallate (EGCG) as a reducing agent. This led to remarkable distinct modes of assembly, AuNP decorated fibrils with NaBH4 reduction or isolated AuNPs with EGCG reduction. For both methodologies, the presence of spherical AuNPs was observed by plasmonic resonance bands in absorption spectra at ∼520 nm. Zeta potential measurements confirmed stable systems, with a similar aggregation state. Circular dichroism spectra revealed an antiparallel β-sheet conformation of the peptides. The transmission electron microscopy (TEM) images showed the coexistence of nanometer fibers and globular nanoparticles with 20 nm size. The small-angle X-ray scattering (SAXS) results show that the NaBH4 systems presented large cylindrical structures, while with increasing P[RF]4 content, a decrease in radius was observed. However, the EGCG-AuNPs were characterized by spherical particles, with a radius of 10–20 nm. Also, the colorimetric efficiency of the hybrids in the capture of Cu2+ ions in solution was monitored. Raman spectroscopy data confirmed the conformation/structure of self-assembled samples. Moreover, there are indications for a surface-enhanced Raman spectroscopy (SERS) effect for Cu2+ sites. The set of results indicates that these systems could act as a promising sensitive metal concentration probes

Relato de caso clinico: Fratura do complexo zigomático orbitário

O osso zigomático é um osso craniano par, que se encontra no terço médio da face. Sua forma é achatada e quadrangular, possuindo três faces (malar, orbital e temporal) e três processos (frontal, maxilar e temporal). Em virtude da sua projeção na face, o complexo zigomático configura-se como uma das regiões de maior acometimento das fraturas faciais gerando complicações não apenas estéticas mas sobretudo funcionais. Deste modo, o objetivo deste trabalho é relatar o caso um paciente do sexo masculino, 42 anos de idade, que compareceu ao Hospital Universitário Maria Aparecida Pedrossian, relatando ser vítima de agressão física, recebendo contra a face objeto contundente. Apresentava assimetria facial às custas de edema em região zigomática a esquerda, equimose, relatando alteração de sensibilidade no trajeto do nervo infra-orbitário ipsilateral bem como desnivelamento ósseo na mesma região a palpação. Ao exame de imagem constatou-se presença de fraturas múltiplas em região de rebordo e parede lateral de órbita, pilares canino e zigomático-maxilar todos do lado esquerdo. Sendo assim, em virtude do quadro optou-se pelo tratamento cirúrgico sob anestesia geral para redução e fixação das fraturas acima. Em pós-operatório imediato o paciente apresentou tanto clinicamente como em exames de imagem bom nivelamento ósseo, dispositivos de fixação em posição e ausência de sinais e sintomas de infecção. O mesmo foi observado em pós-operatórios subsequentes configurando até o momento o resultado satisfatório da terapêutica empregada.  Palavras-chave: Fraturas ósseas. Traumatologia. Zigoma

Tratamento de extenso ferimento facial

Os ferimentos faciais são amplamente classificados de acordo com a sua apresentação e grau de complexidade. Dessa forma, o tratamento envolve a extensão, profundidade, grau de contaminação, o agente etiológico e tempo do trauma, fazendo-se necessária uma abordagem cuidadosa e precisa a fim de restituir a função e estética do paciente. Deste modo, é objetivo apresentar um caso de paciente de 36 anos de idade que procurou atendimento no Hospital Universitário “Maria Aparecida Pedrossian”, queixando-se de trauma em face em virtude de acidente motociclístico, em região rural sem o uso de capacete. Apresentou ferimento extenso em hemiface esquerda, fraturas de maxila, zigoma e mandíbula ipsilateral. Aos exames de imagem constatou-se as fraturas mencionadas no exame clínico. Em virtude da dificuldade do caso bem como a presença de inúmeros corpos estranhos intrabucais optou-se pelo tratamento cirúrgico sob anestesia geral com limpeza, desbridamento dos ferimentos, irrigação abundante com soro fisiológico e iodóforo, exodontia de elementos demasiadamente traumatizados, assim como sutura do extenso ferimento facial com posterior planejamento da osteossíntese das fraturas. Em pós-operatórios o paciente referiu ausência de queixas álgicas e foi orientado quanto à necessidade de cicatrização dos ferimentos, uso das medicações e a necessidade de procedimento cirúrgico para redução e fixação das fraturas. O caso apresentado configura-se como um desafio e a necessidade de postergar o tratamento das fraturas da face foi fundamental a fim de facilitar o melhor resultado estético e, sobretudo funcional.  Palavras-chave: Ferimentos e lesões. Diagnóstico. Terapêutica