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Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues.  相似文献   
3.
Acute and chronic kidney injuries (AKI and CKI) constitute syndromes responsible for a large part of renal failures, and are today still associated with high mortality rates. Given the lack of more effective therapies, there has been intense focus on the use stem cells for organ protective and regenerative effects. Mesenchymal stem cells (MSCs) have shown great potential in the treatment of various diseases of immune character, although there is still debate on its mechanism of action. Thus, for a greater understanding of the role of MSCs, we evaluated the effect of adipose tissue-derived stem cells (AdSCs) in an experimental model of nephrotoxicity induced by folic acid (FA) in FVB mice. AdSC-treated animals displayed kidney functional improvement 24h after therapy, represented by reduced serum urea after FA. These data correlated with cell cycle regulation and immune response modulation via reduced chemokine expression and reduced neutrophil infiltrate. Long-term analyses, 4 weeks after FA, indicated that AdSC treatment reduced kidney fibrosis and chronic inflammation. These were demonstrated by reduced interstitial collagen deposition and tissue chemokine and cytokine expression. Thus, we concluded that AdSC treatment played a protective role in the framework of nephrotoxic injury via modulation of inflammation and cell cycle regulation, resulting in reduced kidney damage and functional improvement, inhibiting organ fibrosis and providing long-term immune regulation.  相似文献   
4.
The aim of this work was to analyse the ultrastructure of storage crypts and stored spermatozoa, and to describe changes during the annual reproductive cycle of the bluemouth Helicolenus dactylopterus dactylopterus , which has internal fertilization and a zygoparous mode of reproduction. Spermatozoa had elongated heads and long midpieces, two characteristics which are thought to be fairly advanced and correlated with internal fertilization, as is the case of the bluemouth. A remarkable spermatozoon feature was the retention of a significant quantity of cytoplasm around the head, a condition that appeared to be related to nourishment during the long storage period, up to 10 months in the intraovarian crystal structures of the female. Male sex cells' protection against the female immune system was ensured by junctional complexes between the crypt cells composed of tight junctions and desmosomes.  相似文献   
5.
Summary The most relevant properties of hypercycles were previously studied mainly from a theoretical point of view. We have developed a Monte Carlo method simulating hypercyclic organization to obtain information about the dynamics of this prebiotic organization. Nucleation, growth, and selective properties have been tested and the results obtained are in good agreement with those of the theoretical predictions. The influence of hypercyclic organization of the error threshold has also been studied. As a consequence of the emergence of a hypercycle, the value of this threshold decreases. The amount of this decrease depends on the population size. Moreover, for some interval of quality factor values, either the hypercycle organization or an error catastrophe can be produced, depending on the initial conditions. The influence of these phenomena on both the dynamic behavior and evolutionary advantages of the hypercycle, as well as their decisive roles on genome size, are discussed.Presented at the FEBS Symposium on Genome Organization and Evolution, held in Crete, Greece, September 1–5, 1986  相似文献   
6.
Two experiments were carried out to evaluate the effect of acidity on bean-Rhizobium competition for nodule sites. SevenPhaseolus vulgaris host cultivars differing in acid-pH tolerance were grown in sand culture, and irrigated using a sub-irrigation system and nutrient solutions of pH 4.5, 5.0, 5.5, and 6.0. A mixed inoculant of two antibiotically markedRhizobium leguminosarum bvphaseoli strains CIAT899 (acid-tolerant) and CIAT632 (acid-sensitive) was used. The acid-tolerant CIAT899 dominated CIAT632 in nodule occupancy across all cultivars and pH treatments. Although several of the varieties had previously been identified as PH-tolerant, and these cultivars performed better than those reported to be acid sensitive, all showed a marked increase in nodulation and plant development when the pH was raised from 4.5 to 6.0. The second experiment using a modified Leonard jar system varied the inoculation ratio between CIAT899 and UMR1116 (acid-sensitive, inefficient in N2-fixation) and contrasted nodulation response for the bean varieties Preto 143 (pH-tolerant) and Negro Argel (pH-sensitive) at 3 pH treatments (4.5, 5.5, 6.5). There was a significant effect of host cultivar, ratio of inoculation, and pH on the percentage of nodule occupancy by each strain. At low pH CIAT899 had higher nodule occupancy than UM1116 in the variety Negro Argel but had the same percentage of nodulation when the variety was Preto 143. Increasing the cell concentration of UMR1116 produced more inefficient nodules at all treatment combinations and reduced plant growth for both cultivars used.  相似文献   
7.
The effect of yeast hulls (yeast ghosts) on sluggish or stuck white wine fermentations was studied. The enhancing effect on yeast growth and fermentation rate displayed by the hulls was shown to be similar to the effect provided by lipid extract from the same hulls. Unsaturated fatty acids and sterols were incorporated into the yeast from lipid extracts during fermentation carried out under oxygen-limited conditions. Adsorption of toxic medium-chain fatty acid (decanoic acid) onto the yeast hulls took place through a dialysis membrane. However, when the hulls were placed inside a dialysis bag, the increase in yeast growth and fermentation rate seen when freely suspended hulls were used did not occur. Accordingly, the effect of yeast hulls in preventing stuck fermentations cannot be attributed only to the adsorption and consequent removal of medium-chain fatty acids from the juice.  相似文献   
8.
Previous work from our laboratory (Biochem. J. 219:689–697 (1984) had shown that hydrocortisone stimulated the net accumulation of the myelin-specific sulfolipid in cultures of cells dissociated from embryonic mouse cerebra. This accumulation caused by hydrocortisone was shown to be due to a decrease of sulfolipid degradation by arylsulfatase A (ASA) and not due to a stimulation of its synthesis by a sulfotransferase. Both ASA activity and the turnover of sulfolipid were decreased by hydrocortisone to 60–62% of untreated cells. In current work the same decrease in enzyme activity was obtained and enzyme linked immunosorbent assays demonstrate that hydrocortisone decreased the number of ASA protein molecules to 61% of untreated cells [(-)hydrocorcortisone 0.31±0.06 ng ASA/g protein; (+)hydrocortisone: 0.18±0.04 ng ASA/g protein]. This decrease in the number of ASA molecules correlates well with the decrease in both the enzyme activity and the sulfolipid turnover, which suggests that the major mode of inhibition of ASA activity by hydrocortisone involves a decrease in the concentration of ASA in the cells rather than some other mechanism of inhibition.The material in this paper has been included in a dissertation submitted by A.J.M. in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Temple University.  相似文献   
9.
Triethyltin intoxication induces, in vivo, a significant increase of malondialdehyde concentration in rat brain. After treatment with a Ginkgo biloba extract, an extract known to possess antiedematous and radical scavenging properties, the malondialdehyde level in the brain is significantly decreased. This suggests that a lipid peroxidation process is associated with cerebral oedema induced by triethyltin.  相似文献   
10.
Thirty litters of C57BL 6J mice were administered intraperitoneally one of four doses (0, 500, 750, and 1,000 mg/kg maternal weight) of acetazolamide on day 9 of gestation. The fetuses were removed on day 18 and fixed, stained, cleared, and examined for the pattern of malformations. The forelimb postaxial limb deficiency was the most common abnormality, but forelimb postaxial polydactyly and a postaxial deficiency in the hindlimb were also observed. Males were significantly more likely to be malformed than females at all doses, in contrast to the predominance of females observed in rat fetuses exposed to acetazolamide (Scott et al.: Teratology 6:239-240, '73). The occurrence of limb malformations did not correlate with maternal weight loss, the birth weight of the fetus, or the position of the fetus in the uterus. A "litter effect" was demonstrated in that there was a nonuniform distribution of litters with different proportions of malformed fetuses.  相似文献   
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