320 research outputs found

    The Influence of Surgical Robotics

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    Over the past thirty years, the presence of surgical robotics has increased dramatically. This type of robot is projected to increased surgical dexterity, decreased recovery time, and overall fewer complications. While surgical robotics is only in its beginnings, it promises to change the medical landscape so that surgeries can be carried out with more precision and accuracy. Many in the medical field are excited by these new developments, as it would lead to better patient care and more successful surgeries. However, there are those who are not convinced that soft robotics is safe for widespread use, due to the current limitations of the technology and materials

    A preferred vision for administering secondary schools : a reflective essay

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    Monroe (1997) said, School should not reflect what society is, but rather school should model what society should be (p. 193). This statement summarizes my reasons for becoming an administrator. Iowa\u27s public schools are some of the finest learning institutions in the nation. These same schools, however, frequently reflect the negative characteristics of society. Lack of respect, segregation of students, and elitist attitudes are prevalent characteristics of today\u27s society and today\u27s schools. I want to be a leader who will make the necessary changes to maintain our high academic standards for all students and make our schools a welcoming place for all students, staff, families, and community members

    Advances in Retinal Tissue Engineering

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    Retinal degenerations cause permanent visual loss and affect millions world-wide. Current treatment strategies, such as gene therapy and anti-angiogenic drugs, merely delay disease progression. Research is underway which aims to regenerate the diseased retina by transplanting a variety of cell types, including embryonic stem cells, fetal cells, progenitor cells and induced pluripotent stem cells. Initial retinal transplantation studies injected stem and progenitor cells into the vitreous or subretinal space with the hope that these donor cells would migrate to the site of retinal degeneration, integrate within the host retina and restore functional vision. Despite promising outcomes, these studies showed that the bolus injection technique gave rise to poorly localized tissue grafts. Subsequently, retinal tissue engineers have drawn upon the success of bone, cartilage and vasculature tissue engineering by employing a polymeric tissue engineering approach. This review will describe the evolution of retinal tissue engineering to date, with particular emphasis on the types of polymers that have routinely been used in recent investigations. Further, this review will show that the field of retinal tissue engineering will require new types of materials and fabrication techniques that optimize the survival, differentiation and delivery of retinal transplant cells.Harvard Univ, Sch Med, Dept Ophthalmol, Schepens Eye Res Inst, Boston, MA 02114 USABoston Univ, Dept Grad Med Sci, Boston, MA 02215 USAUniversidade Federal de São Paulo, Dept Ophthalmol, BR-09210170 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, BR-09210170 São Paulo, BrazilWeb of Scienc

    Francis Thompson: A Metaphysical Poet

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    Ca\u3csup\u3e2+\u3c/sup\u3e Extrusion by NCX is Compromised in Olfactory Sensory Neurons of OMP\u3csup\u3e-/-\u3c/sup\u3e Mice

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    Background: The role of olfactory marker protein (OMP), a hallmark of mature olfactory sensory neurons (OSNs), has been poorly understood since its discovery. The electrophysiological and behavioral phenotypes of OMP knockout mice indicated that OMP influences olfactory signal transduction. However, the mechanism by which this occurs remained unknown. Principal Findings: We used intact olfactory epithelium obtained from WT and OMP-/- mice to monitor the Ca2+ dynamics induced by the activation of cyclic nucleotide-gated channels, voltage-operated Ca2+ channels, or Ca2+ stores in single dendritic knobs of OSNs. Our data suggested that OMP could act to modulate the Ca2+-homeostasis in these neurons by influencing the activity of the plasma membrane Na+/ Ca2+-exchanger (NCX). Immunohistochemistry verifies colocalization of NCX1 and OMP in the cilia and knobs of OSNs. To test the role of NCX activity, we compared the kinetics of Ca2+ elevation by stimulating the reverse mode of NCX in both WT and OMP2/2 mice. The resulting Ca2+ responses indicate that OMP facilitates NCX activity and allows rapid Ca2+ extrusion from OSN knobs. To address the mechanism by which OMP influences NCX activity in OSNs we studied protein-peptide interactions in real-time using surface plasmon resonance technology. We demonstrate the direct interaction of the XIP regulatory-peptide of NCX with calmodulin (CaM). Conclusions: Since CaM also binds to the Bex protein, an interacting protein partner of OMP, these observations strongly suggest that OMP can influence CaM efficacy and thus alters NCX activity by a series of protein-protein interactions. © 2009 Kwon et al

    Sensing and avoiding sick conspecifics requires Gαi2+ vomeronasal neurons

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    Rodents utilize chemical cues to recognize and avoid other conspecifics infected with pathogens. Infection with pathogens and acute inflammation alter the repertoire and signature of olfactory stimuli emitted by a sick individual. These cues are recognized by healthy conspecifics via the vomeronasal or accessory olfactory system, triggering an innate form of avoidance behavior. However, the molecular identity of the sensory neurons and the higher neural circuits involved in the detection of sick conspecifics remain poorly understood

    Chorioretinal Coloboma Complications: Retinal Detachment and Choroidal Neovascular Membrane

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    PURPOSE: To report the chorioretinal coloboma, and its association with increased risk of retinal detachment (RD) and choroidal neovascularization (CNV). METHODS: This retrospective case series included eyes with chorioretinal coloboma diagnosed between 1995 and 2014 with a focus on RD and CNV as related complications. Cases of CNV were managed with laser photocoagulation or intravitreal injection of bevacizumab. For eyes with CNV, therapeutic success was defined as resolution of the subretinal hemorrhage on fundus examination and resolution of the subretinal and intraretinal fluid on optical coherence tomography (OCT). For eyes with RD, anatomic success following surgical intervention was defined as attachment of the retina at the last follow-up visit. RESULTS: Fifty-one eyes of 31 patients with chorioretinal coloboma were identified for review. Bilateral chorioretinal coloboma was present in 64.5% of subjects. RD developed in 15 eyes (29.4%). Among 15 eyes with RD, 4 eyes (27%) had retinal breaks identified within the coloboma, 5 eyes (33%) had retinal breaks outside the coloboma, 2 eyes (13%) showed retinal breaks both inside and outside the coloboma, and in 4 eyes (27%) the causative retinal break was not localized. The overall rate of anatomic success after RD repair was 85.7%. CNV developed in 7 eyes (13.7%) and was located along the margin of the coloboma in all cases. CNV was bilateral in 2 of the 5 affected individuals (40%). CONCLUSION: RD and CNV were present in a high percentage of eyes with chorioretinal coloboma in these series. The frequent finding of retinal breaks outside the coloboma bed suggests that vitreoretinal interface abnormalities may play a role in development of RD in these eyes

    Lifespan extension in female mice by early, transient exposure to adult female olfactory cues

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    Several previous lines of research have suggested, indirectly, that mouse lifespan is particularly susceptible to endocrine or nutritional signals in the first few weeks of life, as tested by manipulations of litter size, growth hormone levels, or mutations with effects specifically on early-life growth rate. The pace of early development in mice can also be influenced by exposure of nursing and weanling mice to olfactory cues. In particular, odors of same-sex adult mice can in some circumstances delay maturation. We hypothesized that olfactory information might also have a sex-specific effect on lifespan, and we show here that the lifespan of female mice can be increased significantly by odors from adult females administered transiently, that is from 3 days until 60 days of age. Female lifespan was not modified by male odors, nor was male lifespan susceptible to odors from adults of either sex. Conditional deletion of the G protein Gαo in the olfactory system, which leads to impaired accessory olfactory system function and blunted reproductive priming responses to male odors in females, did not modify the effect of female odors on female lifespan. Our data provide support for the idea that very young mice are susceptible to influences that can have long-lasting effects on health maintenance in later life, and provide a potential example of lifespan extension by olfactory cues in mice

    BTDAzo: A Photoswitchable TRPC5 Channel Activator

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    Photoswitchable reagents can be powerful tools for high-precision biological control. TRPC5 is a Ca2+-permeable cation channel with distinct tissue-specific roles, from synaptic function to hormone regulation. Reagents giving spatiotemporally-resolved control over TRPC5 activity may be key to understanding and harnessing its biology. Here we develop the first photoswitchable TRPC5-modulator, BTDAzo, to address this goal. BTDAzo can photocontrol TRPC5 currents in cell culture, as well as controlling endogenous TRPC5-based neuronal Ca2+ responses in mouse brain slices. BTDAzos are also the first reported azo-benzothiadiazines, an accessible and conveniently derivatised azoheteroarene with strong two-colour photoswitching. BTDAzo ' s ability to control TRPC5 across relevant channel biology settings makes it suitable for a range of dynamically reversible photoswitching studies in TRP channel biology, with the aim to decipher the various biological roles of this centrally important ion channel

    Newborn Interneurons in the Accessory Olfactory Bulb Promote Mate Recognition in Female Mice

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    In the olfactory bulb of adult rodents, local interneurons are constantly replaced by immature precursors derived from the subventricular zone. Whether any olfactory sensory process specifically relies on this cell renewal remains largely unclear. By using the well known model of mating-induced imprinting to avoid pregnancy block, which requires accessory olfactory bulb (AOB) function, we demonstrate that this olfactory memory formation critically depends on the presence of newborn granule neurons in this brain region. We show that, in adult female mice, exposure to the male urine compounds involved in mate recognition increases the number of new granule cells surviving in the AOB. This process is modulated by male signals sensed through the vomeronasal organ and, in turn, changes the activity of the downstream amygdaloid and hypothalamic nuclei involved in the pregnancy block response. Chemical depletion of newly generated bulbar interneurons causes strong impairment in mate recognition, thus resulting in a high pregnancy failure rate to familiar mating male odors. Taken together, our results indicate that adult neurogenesis is essential for specific brain functions such as persistent odor learning and mate recognition
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