Age-related cognitive impairment and dementia are an increasing societal burden. Epidemiological studies indicate that lifestyle factors, e.g. physical, cognitive and social activities, correlate with reduced dementia risk; moreover, positive effects on cognition of physical/cognitive training have been found in cognitively unimpaired elders. Less is known about effectiveness and action mechanisms of physical/cognitive training in elders already suffering from Mild Cognitive Impairment (MCI), a population at high risk for dementia. We assessed in 113 MCI subjects aged 65–89 years, the efficacy of combined physical-cognitive training on cognitive decline, Gray Matter (GM) volume loss and Cerebral Blood Flow (CBF) in hippocampus and parahippocampal areas, and on brain-blood-oxygenation-level-dependent (BOLD) activity elicited by a cognitive task, measured by ADAS-Cog scale, Magnetic Resonance Imaging (MRI), Arterial Spin Labeling (ASL) and fMRI, respectively, before and after 7 months of training vs. usual life. Cognitive status significantly decreased in MCI-no training and significantly increased in MCI-training subjects; training increased parahippocampal CBF, but no effect on GM volume loss was evident; BOLD activity increase, indicative of neural efficiency decline, was found only in MCI-no training subjects. These results show that a non pharmacological, multicomponent intervention improves cognitive status and indicators of brain health in MCI subjects.

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There is enough evidence that, nowadays, the sedentary lifestyle is one of the major health problems worldwide, linked to many chronic diseases, including mental comorbidities, systemic hypertension, metabolic dysregulation, and cancer. Although health societies recommend engagement to physical activities, there is an overwhelming number of people remaining sedentary, even knowing the health benefits of regular exercises. One of the main factors that justifies this scenario is the lack of motivation, which is a barrier to people intended to start new habits for health. Considering this previous information, new alternatives for exercises may help people engage in a healthier lifestyle. Technology has contributed to this with devices that allow movements based on virtual reality approaches, including the exergames. These are games available even in commercial devices, as video-games, that allow people to work with different physical components. Furthermore, exergames add cognitive gain through its dual-task characteristic. Moreover, due to the combination of these benefits, they are feasible to acquire, and easy to use. Exergames are not only a potential strategy to reduce sedentary lifestyle but also a good method to improve health gains and rehabilitation in different populations and pathological conditions: older adults, stroke survivors, and Parkinson’s disease. In this review, we aim to demonstrate some conditions that literature supports the intervention with exergames due to its physical and cognitive benefits. Furthermore, at the end of this review, we also explore the neurobiological mechanisms behind virtual-reality based exercises.

The genetic diversity of endophytic bacteria in banana ‘Prata Anã’ roots was characterized. Two hundred and one endophytic bacteria were isolated, 151 of which were classified as Gram-positive and 50 as Gram-negative. No hypersensitivity response was observed in any of the isolates. The rep-PCR technique generated different molecular profiles for each primer set (REP, ERIC and BOX). Fifty readable loci were obtained and all of the fragments were polymorphic. Amplified ribosomal DNA restriction analysis (ARDRA) of the isolates based on cleavage with four restriction enzymes yielded 45 polymorphic bands and no monomorphic bands. PCR amplified the nifH gene in 24 isolates. 16S rDNA sequencing of the 201 bacterial isolates yielded 102 high-quality sequences. Sequence analyses revealed that the isolates were distributed among ten bacterial genera (Agrobacterium, Aneurinibacillus, Bacillus, Enterobacter, Klebsiella, Lysinibacillus, Micrococcus, Paenibacillus, Rhizobium and Sporolactobacillus) and included 15 species. The greatest number of isolates belonged to the genus Bacillus. The bacteria identified in this study may be involved in promoting growth, phosphate solubilization, biological control and nitrogen fixation in bananas.

A total of 40 endophytic bacterial isolates obtained from banana tree roots were characterized for their biotechnological potential for promoting banana tree growth. All isolates had at least one positive feature. Twenty isolates were likely diazotrophs and formed pellicles in nitrogen-free culture medium, and 67% of these isolates belonged to the genus Bacillus sp. The isolates EB-04, EB-169, EB-64, and EB-144 had N fixation abilities as measured by the Kjeldahl method and by an acetylene reduction activity assay. Among the 40 isolates, 37.5% were capable of solubilizing inorganic phosphate and the isolates EB-47 and EB-64 showed the highest solubilization capacity. The isolate EB-53 (Lysinibacillus sp.) had a high solubilization index, whereas 73% of the isolates had low solubilization indices. The synthesis of indole-3-acetic acid (IAA) in the presence of L-tryptophan was detected in 40% of the isolates. The isolate EB-40 (Bacillus sp.) produced the highest amount of IAA (47.88 μg/ml) in medium supplemented with L-tryptophan and was able to synthesize IAA in the absence of L-tryptophan. The isolates EB-126 (Bacillus subtilis) and EB-47 (Bacillus sp.) were able to simultaneously fix nitrogen, solubilize phosphate and produce IAA in vitro. The results of this study demonstrated that the isolates analyzed here had diverse abilities and all have the potential to be used as growth-promoting microbial inoculants for banana trees.

The common bean is affected by several pathogens that can cause severe yield losses. Here we report the introgression of resistance genes to anthracnose, angular leaf spot and rust in the Ôcarioca-typeÕ bean cultivar ÔRuda´Õ. Initially, four backcross (BC) lines were obtained using ÔTOÕ, ÔAB 136¢, ÔOuro NegroÕ and ÔAND 277Õ as donor parents. Molecular fingerprinting was used to select the lines genetically closer to the recurrent parent. The relative genetic distances between ÔRuda´Õ and the BC lines varied between 0.0% and 1.99%. The BC lines were intercrossed and molecular markers linked to the resistance genes were used to identify the plants containing the genes of interest. These plants were selfed to obtain the F 2 , F 3 and F 4 plants which were selected based on the presence of the molecular markers mentioned and resistance was confirmed in the F 4 generation by inoculation. Four F 4:7 pyramid lines with all the resistance genes showed resistance spectra equivalent to those of their respective donor parents. Yield tests showed that these lines are as productive as the best Ôcarioca-typeÕ cultivars.

to multiple races of U. appendiculatus, indicating that they are organized in clusters of race-specific genes.Uromyces appendiculatus (Pers.) Unger, the causative fungus of DNA amplification of near isogenic lines (NILs) rust in common beans (Phaseolus vulgaris L.), consists of many patho- Martin et al., 1991) or of contrasting types or pathogenic races. Cultivar Ouro Negro is resistant to most DNA bulks from segregating populations (Michelmore pathotypes detected in Brazil in the last few decades. We attempted et al., 1991) can be used to detect RAPD (Williams et to identify molecular markers linked to a rust resistance gene block present in Ouro Negro. DNA samples extracted from homozygous al., 1990; Welsh and McClelland, 1990) markers in close near isogenic BC 3 F 2:3 lines derived from a cross between susceptible proximity to disease resistance genes. During the develcultivar US Pinto 111 and Ouro Negro were grouped, following greenopment of NILs, these two strategies can be combined house inoculations, into two contrasting bulks, one containing only by constructing DNA bulks from BC n F 2:3 individuals resistant and the other only susceptible plants. The bulks were amplifrom each of two contrasting NILs. This method infied with 605 random primers and two of them amplified bands which creases the chance that markers will be identified close were heteromorphic between the two bulks. These random amplified to the gene of interest (Michelmore et al., 1991; Haley polymorphic DNA (RAPD) bands were transformed into sequence Miklas et al., 1993). characterized amplified regions (SCARs) SCARBA08 and SCARF10. Several RAPD markers associated with genes confer-The rust resistance-susceptibility phenotypes and the molecular genoring resistance to rust in common bean have been identitypes with the two SCAR markers of 303 F 2:3 families from US Pinto fied Haley et al., 1993.; Johnson et 111 ϫ Ouro Negro were determined. SCARBA08 and SCARF10 were determined to be 4.3 Ϯ 1.2 and 6.0 Ϯ 1.3 centimorgans (cM) al., 1995). In some cases, the application of these markfrom the rust resistance locus, respectively. These markers are being ers has been restricted to the laboratories where they used in combination with other markers for resistance to rust, anthracwere identified because of reproducibility problems nose, and angular leaf spot previously identified in our laboratory to

Abstract