234 research outputs found

    Intraparenchymal Striatal Transplants Required for Maintenance of Behavioral Recovery in an Animal Model of Huntington's Disease

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    Rats which receive injections of kainic acid (KA) into the striatum show many of the anatomical, biochemical and behavioral abnormalities seen in patients with Huntington's disease. Recently, it has been reported that fetal striatal transplants into the lesioned striatum could normalize the neurological and behavioral abnormalities produced by the KA lesion. The present study examined the issue of transplant integration in producing behavioral recovery. In one experiment, lesioned animals with transplants located within the lateral ventricle were compared against parenchymally transplanted rats. It was found that unless the ventricular transplant grew into the lesioned striatum there was no recovery. The second experiment demonstrated that electrolytic destruction of a successful fetal striatal transplant could reverse the transplant-induced behavioral recovery. These results suggest that the integrity of the transplant is important in maintaining behavioral recovery. A continuing functional interaction between the host brain and transplanted tissue may be a vital element in the success of the fetal striatal transplant

    Peripheral injection of human umbilical cord blood stimulates neurogenesis in the aged rat brain

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    <p>Abstract</p> <p>Background</p> <p>Neurogenesis continues to occur throughout life but dramatically decreases with increasing age. This decrease is mostly related to a decline in proliferative activity as a result of an impoverishment of the microenvironment of the aged brain, including a reduction in trophic factors and increased inflammation.</p> <p>Results</p> <p>We determined that human umbilical cord blood mononuclear cells (UCBMC) given peripherally, by an intravenous injection, could rejuvenate the proliferative activity of the aged neural stem/progenitor cells. This increase in proliferation lasted for at least 15 days after the delivery of the UCBMC. Along with the increase in proliferation following UCBMC treatment, an increase in neurogenesis was also found in the aged animals. The increase in neurogenesis as a result of UCBMC treatment seemed to be due to a decrease in inflammation, as a decrease in the number of activated microglia was found and this decrease correlated with the increase in neurogenesis.</p> <p>Conclusion</p> <p>The results demonstrate that a single intravenous injection of UCBMC in aged rats can significantly improve the microenvironment of the aged hippocampus and rejuvenate the aged neural stem/progenitor cells. Our results raise the possibility of a peripherally administered cell therapy as an effective approach to improve the microenvironment of the aged brain.</p

    Human Umbilical Cord Blood Treatment in a Mouse Model of ALS: Optimization of Cell Dose

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    Amyotrophic Lateral Sclerosis (ALS) is a multicausal disease characterized by motor neuron degeneration in the spinal cord and brain. Cell therapy may be a promising new treatment for this devastating disorder. We recently showed that a single low dose (10(6) cells) of mononuclear human umbilical cord blood (MNC hUCB) cells administered intravenously to G93A mice delayed symptom progression and modestly prolonged lifespan. The aim of this pre-clinical translation study is to optimize the dose of MNC hUCB cells to retard disease progression in G93A mice. Three different doses of MNC hUCB cells, 10x10(6), 25x10(6) and 50x10(6), were administered intravenously into pre-symptomatic G93A mice. Motor function tests and various assays to determine cell effects were performed on these mice.Our results showed that a cell dose of 25x10(6) cells significantly increased lifespan of mice by 20-25% and delayed disease progression by 15%. The most beneficial effect on decreasing pro-inflammatory cytokines in the brain and spinal cord was found in this group of mice. Human Th2 cytokines were found in plasma of mice receiving 25x10(6) cells, although prevalent human Th1 cytokines were indicated in mice with 50x10(6) cells. High response of splenic cells to mitogen (PHA) was indicated in mice receiving 25x10(6) (mainly) and 10x10(6) cells. Significantly increased lymphocytes and decreased neutrophils in the peripheral blood were found only in animals receiving 25x10(6) cells. Stable reduction in microglia density in both cervical and lumbar spinal cords was also noted in mice administered with 25x10(6) cells.These results demonstrate that treatment for ALS with an appropriate dose of MNC hUCB cells may provide a neuroprotective effect for motor neurons through active involvement of these cells in modulating the host immune inflammatory system response

    Toward Personalized Cell Therapies: Autologous Menstrual Blood Cells for Stroke

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    Cell therapy has been established as an important field of research with considerable progress in the last years. At the same time, the progressive aging of the population has highlighted the importance of discovering therapeutic alternatives for diseases of high incidence and disability, such as stroke. Menstrual blood is a recently discovered source of stem cells with potential relevance for the treatment of stroke. Migration to the infarct site, modulation of the inflammatory reaction, secretion of neurotrophic factors, and possible differentiation warrant these cells as therapeutic tools. We here propose the use of autologous menstrual blood cells in the restorative treatment of the subacute phase of stroke. We highlight the availability, proliferative capacity, pluripotency, and angiogenic features of these cells and explore their mechanistic pathways of repair. Practical aspects of clinical application of menstrual blood cells for stroke will be discussed, from cell harvesting and cryopreservation to administration to the patient

    Aspectos Socioambientais da Produção Pecuária e Agrícola nas Bacias dos Rios do Peixe, Canoas e Pelotas - Santa Catarina.

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    Este trabalho busca caracterizar as principais formas de uso da terra nos 61 municípios compreendidos pelas Bacias do Rio do Peixe, Canoas e Pelotas/SC. Este diagnóstico teve como finalidade subsidiar um plano de gestão dos recursos hídricos superficiais das referidas bacias. A metodologia envolveu além da revisão bibliográfica, a utilização de imagens produto de sensoriamento remoto Landsat TM_05 e CBERS_2 e trabalhos de campo. Também foram resgatados dados sobre a população, produção pecuária, de suínos, bovinos e aves e, principais lavouras (permanentes e temporárias). Os resultados indicam para uso da terra, 34,80% de matas, 31,53% de campos e pastagens, 19,35% de cultivos, 12,53% de silvicultura, 1,15% de corpos d’água e 0,64% de áreas urbanas. A dispersão espacial da criação de suínos e aves concentra-se na Bacia do Rio do Peixe e a de bovinos está dispersa nas 3 bacias. Considerando a agricultura temporária, a cultura do milho acumula maior produção na bacia do Rio do Peixe e está associado à criação de suínos e aves. Com relação à agricultura permanente, destaca-se a produção de uva na Bacia do Rio do Peixe e de maçã nas Bacias dos Rios Canoas e Pelotas. Principalmente nestas, registrou-se um aumento da silvicultura do Pinus entre 1990 e 2010, quando a área total passou de 184.073 para 370.035 hectares. A gestão dos recursos hídricos superficiais e subterrâneos das bacias deverá considerar as áreas de ocorrência das respectivas produções

    Parametric amplification with weak-link nonlinearity in superconducting microresonators

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    Nonlinear kinetic inductance in a high Q superconducting coplanar waveguide microresonator can cause a bifurcation of the resonance curve. Near the critical pumping power and frequency for bifurcation, large parametric gain is observed for signals in the frequency band near resonance. We show experimental results on signal and intermodulation gain which are well described by a theory of the parametric amplification based on a Kerr nonlinearity. Phase dependent gain, or signal squeezing, is verified with a homodyne detection scheme.Comment: Submitted to Physica Scripta, topical issue: Nobel Symposium on Quantum Bits, 2009. 10 pages, 5 figures. Version 2 contains a few new sentences about the current-phase relation of weak link

    Colloids as Mobile Substrates for the Implantation and Integration of Differentiated Neurons into the Mammalian Brain

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    Neuronal degeneration and the deterioration of neuronal communication lie at the origin of many neuronal disorders, and there have been major efforts to develop cell replacement therapies for treating such diseases. One challenge, however, is that differentiated cells are challenging to transplant due to their sensitivity both to being uprooted from their cell culture growth support and to shear forces inherent in the implantation process. Here, we describe an approach to address these problems. We demonstrate that rat hippocampal neurons can be grown on colloidal particles or beads, matured and even transfected in vitro, and subsequently transplanted while adhered to the beads into the young adult rat hippocampus. The transplanted cells have a 76% cell survival rate one week post-surgery. At this time, most transplanted neurons have left their beads and elaborated long processes, similar to the host neurons. Additionally, the transplanted cells distribute uniformly across the host hippocampus. Expression of a fluorescent protein and the light-gated glutamate receptor in the transplanted neurons enabled them to be driven to fire by remote optical control. At 1-2 weeks after transplantation, calcium imaging of host brain slice shows that optical excitation of the transplanted neurons elicits activity in nearby host neurons, indicating the formation of functional transplant-host synaptic connections. After 6 months, the transplanted cell survival and overall cell distribution remained unchanged, suggesting that cells are functionally integrated. This approach, which could be extended to other cell classes such as neural stem cells and other regions of the brain, offers promising prospects for neuronal circuit repair via transplantation of in vitro differentiated, genetically engineered neurons
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