615 research outputs found

    Meeting Forest Restoration Challenges: Using the Target Plant Concept

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    Meeting forest restoration challenges relies on successful establishment of plant materials (e.g., seeds, cuttings, rooted cuttings, or seedlings, etc.; hereafter simply “seedlingsâ€). The Target Plant Concept (TPC) provides a flexible framework that nursery managers and their clients can use to improve the survival and growth of these seedlings. The key tenets of the TPC are that (1) more emphasis is placed on how seedlings perform on the outplanting site rather than on nursery performance, (2) a partnership exists between the nursery manager and the client to determine the target plant based on site characteristics, and (3) that information gleaned from post-planting monitoring is used to improve subsequent plant materials. Through the nursery manager–client partnership, answers to a matrix of interrelated questions define a target plant to meet the reforestation or forest restoration objectives. These questions focus on project objectives; site characteristics, limiting factors, and possible mitigation efforts; species and genetic criteria; stocktype; outplanting tools and techniques; and outplanting window. We provide examples from the southeastern United States, Hawai‛i, and Lebanon on how the TPC process has improved performance of seedlings deployed for reforestation and forest restoration

    Diurnal patterns of soluble amyloid precursor protein metabolites in the human central nervous system

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    The amyloid-β (Aβ) protein is diurnally regulated in both the cerebrospinal fluid and blood in healthy adults; circadian amplitudes decrease with aging and the presence of cerebral Aβ deposits. The cause of the Aβ diurnal pattern is poorly understood. One hypothesis is that the Amyloid Precursor Protein (APP) is diurnally regulated, leading to APP product diurnal patterns. APP in the central nervous system is processed either via the β-pathway (amyloidogenic), generating soluble APP-β (sAPPβ) and Aβ, or the α-pathway (non-amyloidogenic), releasing soluble APP-α (sAPPα). To elucidate the potential contributions of APP to the Aβ diurnal pattern and the balance of the α- and β- pathways in APP processing, we measured APP proteolytic products over 36 hours in human cerebrospinal fluid from cognitively normal and Alzheimer's disease participants. We found diurnal patterns in sAPPα, sAPPβ, Aβ40, and Aβ42, which diminish with increased age, that support the hypothesis that APP is diurnally regulated in the human central nervous system and thus results in Aβ diurnal patterns. We also found that the four APP metabolites were positively correlated in all participants without cerebral Aβ deposits. This positive correlation suggests that the α- and β- APP pathways are non-competitive under normal physiologic conditions where APP availability may be the limiting factor that determines sAPPα and sAPPβ production. However, in participants with cerebral Aβ deposits, there was no correlation of Aβ to sAPP metabolites, suggesting that normal physiologic regulation of cerebrospinal fluid Aβ is impaired in the presence of amyloidosis. Lastly, we found that the ratio of sAPPβ to sAPPα was significantly higher in participants with cerebral Aβ deposits versus those without deposits. Therefore, the sAPPβ to sAPPα ratio may be a useful biomarker for cerebral amyloidosis

    Nerve Agent Hydrolysis Activity Designed into a Human Drug Metabolism Enzyme

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    Organophosphorus (OP) nerve agents are potent suicide inhibitors of the essential neurotransmitter-regulating enzyme acetylcholinesterase. Due to their acute toxicity, there is significant interest in developing effective countermeasures to OP poisoning. Here we impart nerve agent hydrolysis activity into the human drug metabolism enzyme carboxylesterase 1. Using crystal structures of the target enzyme in complex with nerve agent as a guide, a pair of histidine and glutamic acid residues were designed proximal to the enzyme's native catalytic triad. The resultant variant protein demonstrated significantly increased rates of reactivation following exposure to sarin, soman, and cyclosarin. Importantly, the addition of these residues did not alter the high affinity binding of nerve agents to this protein. Thus, using two amino acid substitutions, a novel enzyme was created that efficiently converted a group of hemisubstrates, compounds that can start but not complete a reaction cycle, into bona fide substrates. Such approaches may lead to novel countermeasures for nerve agent poisoning

    Preterm Infants’ Follow-Up Program at a Public Hospital in Buenos Aires: Two-Decade Study

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    Objectives: To analyze temporal trends of mortality, morbidity, growth and neurodevelopment until 2 years of corrected age (CA) of very low birth weight infants (VLBWI) born between 1986- 2005 in Ramon Sardá Maternal Infant Hospital (RSMIH). Methods: Descriptive temporal trend study divided in 5 quinquenniums.1255 VLBWI were born at RSMIH between 1986-2005; 46 were excluded (genetic syndromes, major congenital malformations, confirmed intrauterine infections), 84 were referred out and 1125 were studied. Birth weight (BW), gestational age (GA); morbidity; growth; neurodevelopment at 1 and 2 years of CA; neurological and sensorial disorders, antenatal steroids use, breastfeeding; rehospitalizations; mothers´ age and years of schooling and Unsatisfied Basic Needs Index (UBNI) were recorded. Results: Survival rates increased during the last two periods, especially in <1000g BW infants despite the decrease in GA and BW. Children receiving surfactant (Sf), parenteral nutrition (PN) and antenatal steroids (AS) in the last quinquennium obtained better results in growth (40 weeks GA and 1 CA). The use of these therapies increased greatly in the last decade. Also breastfeeding at 40 weeks GA and 4 months tended to be better. Bronchopulmonary dysplasia (BPD) increased. Rehospitalizations (majorly attributable to lower tract infections) and UBNI stayed equal all along. Mothers’ years of schooling increased a little in the last two quinquenniums. Conclusion: In the last quinquennium children tended to be smaller in GA and BW due to an increase in the survival rate as a result of higher technology and appropriate interventions such as AS, PN, Sf, etc

    Bartonella spp. isolated from wild and domestic ruminants in North America.

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    Bartonella species were isolated from 49% of 128 cattle from California and Oklahoma, 90% of 42 mule deer from California, and 15% of 100 elk from California and Oregon. Isolates from all 63 cattle, 14 deer, and 1 elk had the same polymerase chain reaction/restriction fragment length polymorphism profiles. Our findings indicate potential for inter- and intraspecies transmission among ruminants, as well as risk that these Bartonella spp. could act as zoonotic agents

    Early access schemes for innovative health technologies: the views of international stakeholders

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    This is the final version. Available on open access from Cambridge University Press via the DOI in this recordOBJECTIVES: Early access schemes (EASs) are approaches used by payers to balance and facilitate earlier patient access to innovative health technologies while evidence generation is ongoing. Schemes require investment from payers and are associated with significant risk since not all technologies will be routinely reimbursed. The purpose of this study was to gain the perspectives of policy experts about the key challenges for EASs and potential solutions for their optimal design and implementation. METHODS: Two virtual workshops were convened including (i) UK-based policy experts (England, Wales, and Scotland) and (ii) representatives from multiple healthcare systems (England, France, Sweden, Canada, Poland, and Norway). Participants were encouraged to share their experiences with EASs in their healthcare system and highlight key challenges for policy makers. Discussions were transcribed and analyzed using framework analysis. RESULTS: Participants agreed that EASs have value when targeted toward innovative technologies with the potential for significant clinical benefit in an area of high unmet need. Participants discussed potential solutions to the challenges faced by payers implementing EASs, including defining eligibility criteria, supporting evidence generation, and approaches to reimbursement. CONCLUSIONS: Participants agreed that EASs are one possible solution for their healthcare systems and have the potential to deliver significant clinical value to patients. However, widespread adoption of EASs is limited due to concerns about the risks for patients and healthcare budgets, further solutions are needed to deliver EASs for targeted therapies.NHS Englan

    Advanced optical imaging in living embryos

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    Developmental biology investigations have evolved from static studies of embryo anatomy and into dynamic studies of the genetic and cellular mechanisms responsible for shaping the embryo anatomy. With the advancement of fluorescent protein fusions, the ability to visualize and comprehend how thousands to millions of cells interact with one another to form tissues and organs in three dimensions (xyz) over time (t) is just beginning to be realized and exploited. In this review, we explore recent advances utilizing confocal and multi-photon time-lapse microscopy to capture gene expression, cell behavior, and embryo development. From choosing the appropriate fluorophore, to labeling strategy, to experimental set-up, and data pipeline handling, this review covers the various aspects related to acquiring and analyzing multi-dimensional data sets. These innovative techniques in multi-dimensional imaging and analysis can be applied across a number of fields in time and space including protein dynamics to cell biology to morphogenesis

    Recovery of visual fields in brain-lesioned patients by reaction perimetry treatment

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    <p>Abstract</p> <p>Background</p> <p>The efficacy of treatment in hemianopic patients to restore missing vision is controversial. So far, successful techniques require laborious stimulus presentation or restrict improvements to selected visual field areas. Due to the large number of brain-damaged patients suffering from visual field defects, there is a need for an efficient automated treatment of the total visual field.</p> <p>Methods</p> <p>A customized treatment was developed for the reaction perimeter, permitting a time-saving adaptive-stimulus presentation under conditions of maximum attention. Twenty hemianopic patients, without visual neglect, were treated twice weekly for an average of 8.2 months starting 24.2 months after the insult. Each treatment session averaged 45 min in duration.</p> <p>Results</p> <p>In 17 out of 20 patients a significant and stable increase of the visual field size (average 11.3° ± 8.1) was observed as well as improvement of the detection rate in the defective visual field (average 18.6% ± 13.5). A two-factor cluster analysis demonstrated that binocular treatment was in general more effective in augmenting the visual detection rate than monocular. Four out of five patients with a visual field increase larger than 10° suffered from hemorrhage, whereas all seven patients with an increase of 5° or less suffered from infarction. Most patients reported that visual field restoration correlated with improvement of visual-related activities of daily living.</p> <p>Conclusion</p> <p>Rehabilitation treatment with the Lubeck Reaction Perimeter is a new and efficient method to restore part of the visual field in hemianopia. Since successful transfer of treatment effects to the occluded eye is achieved under monocular treatment conditions, it is hypothesized that the damaged visual cortex itself is the structure in which recovery takes place.</p
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