What is the effect of vigorous exercise on the brain?

Abstract Aims: This study aimed to verify whether vigorous exercise is capable of generating mental fatigue. Methods: To do so, 16 young adult male (29.4 ± 5.2 years old) cyclists (5.4 ± 4.6 years of training) underwent three visits: 1) control session (rest); 2) session with cognitive demand (20 minutes of AX-CPT); 3) session with vigorous exercise (10km time trial). Mental fatigue was assessed using the visual analog scale of fatigue in the pre-and post-session moments. A two-way ANOVA of repeated measures followed by the Bonferroni posthoc was used to verify the effect of the condition (control, cognitive demand, and exercise) and time (pre and post) interaction. The paired "t" test was used to compare the delta of mental fatigue (post - pre) of the sessions. The partial eta squared was used to determine the effect size of the variance. The significance adopted was p < 0.05. Results: A condition x time interaction was observed (F (2.30) = 5.349, p = 0.010, partial η2 = 0.263). When comparing the deltas, a mean difference was found between the control and vigorous exercise (p = 0.033) conditions and cognitive demand and vigorous exercise (p = 0.017) conditions. Control and cognitive demand sessions showed no difference (p = 0.801). Conclusion: The findings suggest that intense physical exercise seems to cause mental fatigue after practice.

Regression and simulation models for human and baboon brain parameters / Modelo regresivo y simulación para los parámetros cerebrales humanos y del babuino

The variations in morphometric parameter of mammalian brains may be influenced by process of functional complexity, evolution and adaptation. Comparative analysis of linear measurements of cerebrum in the human and baboon has shown morphometric differences. In the present study linear measurements from human and baboon cerebrum (n=10 each) were used to predict various values for human and baboon brain and body parameters through multiple regression models. The average brain weights were found to be 2.08 percent and 0.84 percent of the body weights for humans and baboons respectively. The elasticity of regression models revealed that unit percentage increase in Occipital-Frontal (OF) distance would increase the human brain weight by 66.19 percent, while the baboon brain weight would increase by 7.63 percent. The unit percentage increase in the Height of Temporal Lobe (HTL) would increase the human brain weight by 16.28 percent, while the baboon brain weight would increase by only 0.28 percent. Unit percentage increase in Frontal-Temporal (FT) distance would decrease the human and baboon brain weights by 14.04 percent and 0.46 percent respectively. Inter-species values were also predicted through simulation techniques by using the ratios of model parameters with application of programming language Python. The OF, FT and HTL values for human were found to be 2.01 times, 1.55 times and 1.91 times respectively to that of baboon.

Las variaciones en los parámetros morfométricos del cerebro de los mamíferos pueden estar influenciadas por el proceso de complejidad funcional de la evolución y adaptación. Análisis comparativo de las mediciones lineales del cerebro en el humano y babuino han puesto de manifiesto las diferencias morfométricas. En este estudio las mediciones lineales del cerebro humano y babuinos (n = 10 cada uno) fueron utilizados para predecir los valores distintivos para el cerebro de humanos y monos babuinos y los parámetros del cuerpo a través de modelos de regresión múltiple. El peso medio del cerebro resultó ser 2,08 por ciento y 0,84 por ciento del peso corporal de los seres humanos y los babuinos, respectivamente. La elasticidad de los modelos de regresión reveló que el aumento de una unidad porcentual en la distancia occipital-frontal (DE) aumentaría el peso del cerebro humano en 66,19 por ciento, mientras que el peso del cerebro babuino se incrementaría en 7,63 por ciento. El porcentaje de aumento en la altura de lóbulo temporal (HTL) aumentaría el peso del cerebro humano en 16,28 por ciento, mientras que el peso del cerebro babuino aumentaría en sólo el 0,28 por ciento. Si aumenta la distancia frontal-temporal (FT) se reduciría el peso del cerebro humano y babuinos en 14,04 por ciento y 0,46 por ciento, respectivamente. También se prevéen valores entre las especies a través de técnicas de simulación, mediante el uso de proporciones de los parámetros del modelo con la aplicación del lenguaje de programación Python. Los valores humanos de DE, FT y HTL resultaron ser 2,01, 1,55 y 1,91 veces, respectivamente con respecto a la de los babuinos.

Dynamic change of parasites in the brains of BALB/c mice infected with Angiostrongylus cantonensis / 中国人兽共患病学报

To observe the dynamic change of parasites in the brains of BALB/c mice infected with Angiostrongylus cantonensis in order to explore its possible mechanism of pathogenesis', BALB/c mice infected with the III stage larvae of A.cantonensis were observed and killed in different times after infection. The number and distribution of parasites in the brains of the infected mice were observed microscopically and macroscopically. It was found that the larvae of A.cantonensis were distributed in the cerebrum and cerebellum of mice in accordance with the rule of parasitization of worms in the host, i.e.multiplication at first and then dropping in number. And the places where the parasites located were damaged due to mechanical action or inflammatory reactions. The time of onset of symptoms, such as ataxia and twitch was coincided with the dynamic changes in the brains of the infected mice.

Anatomopathological study in BALB/c mice brains experimentally infected with Toxoplasma gondii

Toxoplasmosis is one of the most important diseases of the nervous central system, leading to severe symptoms and, many times, irreversible sequelae. This work demonstrated the main anatomopathological lesions caused by Toxoplasma gondii in brains from experimentally infected BALB/c mice. We analyzed 51 cases of mice that developed toxoplasmosis after experimental infection by intraperitoneal inoculation of blood, amniotic liquid and cerebrospinal fluid from fetuses, newly born children and pregnant women with clinical and laboratory signals of toxoplasmosis. In all experiments where we detected the parasite in mice we also detected pathological lesions in the animal brains with great polymorphism between experiments. Edema was the most found lesion in all cases. Besides, it was possible to demonstrate the inflammatory process in 82.4 percent of cases and necrosis in 64.7 percent of cases, in agreement with the literature that describes severe neurological damage in its hosts.

The Principle of the Work of the Indraught of the Foreign Brains in the Higher Learning / 中华医学教育探索杂志

The principle of the indraught of the foreign brains in the higher learning includes six aspects: serving our development of the colleges and universities;retaining the foreign experts according to our demand;the professors being the principal part of the work;benefiting both sides from the work and avoiding the harm;digesting,absorbing,improving,and innovating;in pursuit of the efficiency of the work.

Effects of leukemia inhibitor factors on the proliferation and differentiation of cultured human neural stem cells(hNSC) derived from the fetal brains / 中国免疫学杂志

0.05) . No significant differences were observed between the expansion folds of hNSC derived from various fetal brain samples when cultured under the same conditions. LIF played great roles on cell proliferation,in LIF + groups, hNSC cell number increased ranging from 4 000-8 400 folds, no cell differentiation occurred; and in LIF" groups,only 43 to 96 folds.The differentiation phenomenons were watched when cultured more than two months. In the course of cell culturing, observed that the effects of LIF on hNSC expansion were obviously demonstrated 50-60 days after inoculation.The number of neurons and astrocytes differentiated from the cultured hNSC were respectively identified by means of Immuno-cytochemical fluorescent assay, and the percentages of neurons(as a proportion of neuron and astrocyte number) were calculated,which were ranging from 12% to 83% in LIF+ cultures, significantly higher than 8% to 23% in LIF- ones(P