Implications of neurovascular uncoupling in functional magnetic resonance imaging (fMRI) of brain tumors.

PubMed

Pak, Rebecca W; Hadjiabadi, Darian H; Senarathna, Janaka; Agarwal, Shruti; Thakor, Nitish V; Pillai, Jay J; Pathak, Arvind P

2017-11-01

Functional magnetic resonance imaging (fMRI) serves as a critical tool for presurgical mapping of eloquent cortex and changes in neurological function in patients diagnosed with brain tumors. However, the blood-oxygen-level-dependent (BOLD) contrast mechanism underlying fMRI assumes that neurovascular coupling remains intact during brain tumor progression, and that measured changes in cerebral blood flow (CBF) are correlated with neuronal function. Recent preclinical and clinical studies have demonstrated that even low-grade brain tumors can exhibit neurovascular uncoupling (NVU), which can confound interpretation of fMRI data. Therefore, to avoid neurosurgical complications, it is crucial to understand the biophysical basis of NVU and its impact on fMRI. Here we review the physiology of the neurovascular unit, how it is remodeled, and functionally altered by brain cancer cells. We first discuss the latest findings about the components of the neurovascular unit. Next, we synthesize results from preclinical and clinical studies to illustrate how brain tumor induced NVU affects fMRI data interpretation. We examine advances in functional imaging methods that permit the clinical evaluation of brain tumors with NVU. Finally, we discuss how the suppression of anomalous tumor blood vessel formation with antiangiogenic therapies can "normalize" the brain tumor vasculature, and potentially restore neurovascular coupling.

Major neurovascular complications of clavicle fracture surgery

PubMed Central

Clitherow, Harry DS

2014-01-01

Clavicle fracture fixation is becoming an increasingly common operation, with good clinical outcomes and a low rate of significant complications. However, there are several reports of rare but potentially life or limb threatening, neurovascular complications. Arterial injuries are usually pseudoaneurysms associated with prominent screws. These may be clinically silent for several years before presenting as subcritical upper limb ischaemia. Venous injuries are a result of tearing of the vessel wall by fracture manipulation, drills or implants. This produces intra-operative haemorrhage and potentially air embolism, which can be fatal if not rapidly recognized and managed. Brachial plexopathy is the result of traction on adherent plexus or impingement by fracture fragments or callus. It presents as severe arm pain and paralysis immediately postoperatively. Neurovascular injuries can be avoided by a combination of pre-operative planning, communication with anaesthetic staff and strategic surgical technique. The plane of the surgical exposure, release of the soft tissues, drill direction and depth and screw length are all important factors. PMID:27582950

Osteosynthesis for clavicle fractures: How close are we to penetration of neurovascular structures?

PubMed

Stillwell, A; Ioannou, C; Daniele, L; Tan, S L E

2017-02-01

Risks associated with drill plunging are well recognised in clavicle osteosynthesis. To date no studies have described plunge depth associated with clavicle osteosynthesis. To determine whether plunge depth associated with clavicle osteosynthesis is great enough to penetrate neurovascular structures and whether surgical experience reduces the risk of neurovascular injury METHOD: Cadaveric clavicles were pressed into spongy phenolic foam to allow measurement of drill bit penetration beyond the far cortex (plunge depth). 15 surgeons grouped according to experience were asked to drill a single hole in the medial, middle and lateral clavicle in 2 specimens each. Each surgeon used fully a charged standard Stryker drill with a new 2.6mm drill bit and guide. Plunge depths were measured in 0.5mm increments. Depth measurements were compared amongst groups and to previously documented distances to neurovascular structures as outlined by Robinson et al. Kruskal-Wallis test was used for overall comparison and Mann-Whitney U test was used for comparing the groups individually. Mean plunge depth across all groups was 3.4mm, (0.5-6.5), 4.0mm (1mm-8.5mm) and 4.0mm (0.5mm-15mm) in the medial, middle and lateral clavicle. Plunge depths were greater than previously documented distances to the subclavian vein at the medial clavicle on nine occasions. Plunge depths in the middle and lateral clavicle were well within the previously documented distances from neurovascular structures. There was no correlation between level of experience and median plunge depth (p=0.18). However, inexperienced surgeons plunged 1mm greater than intermediate and experienced surgeons (p=0.026). There was one significant outlier; a 15mm plunge depth by an inexperienced surgeon in the lateral clavicle. Clavicle osteosynthesis has a relatively high risk of neurovascular injury. Plunge depths through the clavicle often exceed the distance of neurovascular structures, especially in the medial clavicle. A thorough

Dual energy CT at the synchrotron: a piglet model for neurovascular research.

PubMed

Schültke, Elisabeth; Kelly, Michael E; Nemoz, Christian; Fiedler, Stefan; Ogieglo, Lissa; Crawford, Paul; Paterson, Jessica; Beavis, Cole; Esteve, Francois; Brochard, Thierry; Renier, Michel; Requardt, Herwig; Dallery, Dominique; Le Duc, Geraldine; Meguro, Kotoo

2011-08-01

Although the quality of imaging techniques available for neurovascular angiography in the hospital environment has significantly improved over the last decades, the equipment used for clinical work is not always suited for neurovascular research in animal models. We have previously investigated the suitability of synchrotron-based K-edge digital subtraction angiography (KEDSA) after intravenous injection of iodinated contrast agent for neurovascular angiography in radiography mode in both rabbit and pig models. We now have used the KEDSA technique for the acquisition of three-dimensional images and dual energy CT. All experiments were conducted at the biomedical beamline ID 17 of the European Synchrotron Radiation Facility (ESRF). A solid state germanium (Ge) detector was used for the acquisition of image pairs at 33.0 and 33.3 keV. Three-dimensional images were reconstructed from an image series containing 60 single images taken throughout a full rotation of 360°. CT images were reconstructed from two half-acquisitions with 720 projections each. The small detector field of view was a limiting factor in our experiments. Nevertheless, we were able to show that dual energy CT using the KEDSA technique available at ID 17 is suitable for neurovascular research in animal models. Copyright © 2010. Published by Elsevier Ireland Ltd.

Non-Traumatic Anterior Dislocation of a Total Knee Replacement Associated with Neurovascular Injury

PubMed Central

Aderinto, Joseph; Gross, Allan E; Rittenhouse, Bryan

2009-01-01

Prosthetic total knee replacements rarely dislocate. When dislocation does occur, it is usually in a posterior direction in association with a posterior stabilised, cruciate-sacrificing prosthesis. Neurovascular injury is unusual. In this report, we describe a case of anterior dislocation of a cruciate-retaining total knee replacement in a 67-year-old woman. The dislocation occurred in the absence of overt trauma and resulted in severe neurovascular injury. PMID:19686618

Caloric restriction preserves memory and reduces anxiety of aging mice with early enhancement of neurovascular functions.

PubMed

Parikh, Ishita; Guo, Janet; Chuang, Kai-Hsiang; Zhong, Yu; Rempe, Ralf G; Hoffman, Jared D; Armstrong, Rachel; Bauer, Björn; Hartz, Anika M S; Lin, Ai-Ling

2016-11-08

Neurovascular integrity plays an important role in protecting cognitive and mental health in aging. Lifestyle interventions that sustain neurovascular integrity may thus be critical on preserving brain functions in aging and reducing the risk for age-related neurodegenerative disorders. Here we show that caloric restriction (CR) had an early effect on neurovascular enhancements, and played a critical role in preserving vascular, cognitive and mental health in aging. In particular, we found that CR significantly enhanced cerebral blood flow (CBF) and blood-brain barrier function in young mice at 5-6 months of age. The neurovascular enhancements were associated with reduced mammalian target of rapamycin expression, elevated endothelial nitric oxide synthase signaling, and increased ketone bodies utilization. With age, CR decelerated the rate of decline in CBF. The preserved CBF in hippocampus and frontal cortex were highly correlated with preserved memory and learning, and reduced anxiety, of the aging mice treated with CR (18-20 months of age). Our results suggest that dietary intervention started in the early stage (e.g., young adults) may benefit cognitive and mental reserve in aging. Understanding nutritional effects on neurovascular functions may have profound implications in human brain aging and age-related neurodegenerative disorders.

Transient ischemic attack: management in the emergency department and impact of an outpatient neurovascular clinic.

PubMed

Hosier, Gregory W; Phillips, Stephen J; Doucette, Steve P; Magee, Kirk D; Gubitz, Gordon J

2016-09-01

1) To evaluate whether transient ischemic attack (TIA) management in emergency departments (EDs) of the Nova Scotia Capital District Health Authority followed Canadian Best Practice Recommendations, and 2) to assess the impact of being followed up in a dedicated outpatient neurovascular clinic. Retrospective chart review of all patients discharged from EDs in our district from January 1, 2011 to December 31, 2012 with a diagnosis of TIA. Cox proportional hazards models, Kaplan-Meier survival curve, and propensity matched analyses were used to evaluate 90-day mortality and readmission. Of the 686 patients seen in the ED for TIA, 88.3% received computed tomography (CT) scanning, 86.3% received an electrocardiogram (ECG), 35% received vascular imaging within 24 hours of triage, 36% were seen in a neurovascular clinic, and 4.2% experienced stroke, myocardial infarction, or vascular death within 90 days. Rates of antithrombotic use were increased in patients seen in a neurovascular clinic compared to those who were not (94% v. 86.3%, p<0.0001). After adjustment for age, sex, vascular disease risk factors, and stroke symptoms, the risk of readmission for stroke, myocardial infarction, or vascular death was lower for those seen in a neurovascular clinic compared to those who were not (adjusted hazard ratio 0.28; 95% confidence interval 0.08-0.99, p=0.048). The majority of patients in our study were treated with antithrombotic agents in the ED and investigated with CT and ECG within 24 hours; however, vascular imaging and neurovascular clinic follow-up were underutilized. For those with neurovascular clinic follow-up, there was an association with reduced risk of subsequent stroke, myocardial infarction, or vascular death.

The neurovascular unit, matrix proteases, and innate inflammation.

PubMed

del Zoppo, Gregory J

2010-10-01

In the central nervous system, microvessel-neuron interactions appear highly coordinated. The rapid simultaneous responses of the microvasculature, neurons, and glia to focal ischemia in experimental ischemic stroke suggest that these responses could be viewed in a unitary fashion, rather than as individual components. The "neurovascular unit" consists of microvessels (endothelial cells-basal lamina matrix-astrocyte end-feet [and pericytes]), astrocytes, neurons and their axons, and other supporting cells that are likely to modulate the function of the "unit." Each cell component generates an inflammatory response to ischemia. Matrix metalloproteinase (MMP)-9 was first associated with hemorrhagic transformation following focal ischemia in an experimental model. A series of studies of ischemic stroke patients also suggests a relationship between MMP-9 levels and several consequences of ischemic injury, including hemorrhagic transformation. Recent experimental work suggests specific cell sources for MMP-9 generation and for matrix proteases from four distinct families that could impact neurovascular unit integrity. © 2010 New York Academy of Sciences.

Caloric restriction preserves memory and reduces anxiety of aging mice with early enhancement of neurovascular functions

PubMed Central

Parikh, Ishita; Guo, Janet; Chuang, Kai-Hsiang; Zhong, Yu; Rempe, Ralf G.; Hoffman, Jared D.; Armstrong, Rachel; Bauer, Björn; Hartz, Anika M.S.; Lin, Ai-Ling

2016-01-01

Neurovascular integrity plays an important role in protecting cognitive and mental health in aging. Lifestyle interventions that sustain neurovascular integrity may thus be critical on preserving brain functions in aging and reducing the risk for age-related neurodegenerative disorders. Here we show that caloric restriction (CR) had an early effect on neurovascular enhancements, and played a critical role in preserving vascular, cognitive and mental health in aging. In particular, we found that CR significantly enhanced cerebral blood flow (CBF) and blood-brain barrier function in young mice at 5-6 months of age. The neurovascular enhancements were associated with reduced mammalian target of rapamycin expression, elevated endothelial nitric oxide synthase signaling, and increased ketone bodies utilization. With age, CR decelerated the rate of decline in CBF. The preserved CBF in hippocampus and frontal cortex were highly correlated with preserved memory and learning, and reduced anxiety, of the aging mice treated with CR (18-20 months of age). Our results suggest that dietary intervention started in the early stage (e.g., young adults) may benefit cognitive and mental reserve in aging. Understanding nutritional effects on neurovascular functions may have profound implications in human brain aging and age-related neurodegenerative disorders. PMID:27829242

Relationship of Neurovascular Elements to Neuron Injury during Ischemia

PubMed Central

del Zoppo, Gregory J.

2009-01-01

Occlusion of flow to the brain regions identifies regions of vulnerability within the vascular territory at risk, which coalesce to become the mature ischemic lesion. A large number of unsuccessful clinical trials have focused on neuron and extravascular targets in humans that have shown apparent salvage in preclinical models. However, the observation that microvessel and neuron responses to ischemia occur simultaneously in these regions suggest that the responses could be coordinated. This presentation examines evidence in support of the conceptual ‘neurovascular unit’ and its application to the setting of acute intervention trials in ischemic stroke. There are no uniform reasons for which nonvascular interventions, as a class, have not been successful in clinical trials, but both the clinical observations and the hypothesis imply the need to understand interactions with the neurovascular unit as a prelude to further neuron protectant trials. PMID:19342834

In Vivo Analysis of the Neurovascular Niche in the Developing Xenopus Brain

PubMed Central

Li, Jianli

2017-01-01

Abstract The neurovascular niche is a specialized microenvironment formed by the interactions between neural progenitor cells (NPCs) and the vasculature. While it is thought to regulate adult neurogenesis by signaling through vascular-derived soluble cues or contacted-mediated cues, less is known about the neurovascular niche during development. In Xenopus laevis tadpole brain, NPCs line the ventricle and extend radial processes tipped with endfeet to the vascularized pial surface. Using in vivo labeling and time-lapse imaging in tadpoles, we find that intracardial injection of fluorescent tracers rapidly labels Sox2/3-expressing NPCs and that vascular-circulating molecules are endocytosed by NPC endfeet. Confocal imaging indicates that about half of the endfeet appear to appose the vasculature, and time-lapse analysis of NPC proliferation and endfeet-vascular interactions suggest that proliferative activity does not correlate with stable vascular apposition. Together, these findings characterize the neurovascular niche in the developing brain and suggest that, while signaling to NPCs may occur through vascular-derived soluble cues, stable contact between NPC endfeet and the vasculature is not required for developmental neurogenesis. PMID:28795134

Chronic stress induced disruption of the peri-infarct neurovascular unit following experimentally induced photothrombotic stroke.

PubMed

Zhao, Zidan; Ong, Lin Kooi; Johnson, Sarah; Nilsson, Michael; Walker, Frederick R

2017-12-01

How stress influences brain repair is an issue of considerable importance, as patients recovering from stroke are known to experience high and often unremitting levels of stress post-event. In the current study, we investigated how chronic stress modified the key cellular components of the neurovascular unit. Using an experimental model of focal cortical ischemia in male C57BL/6 mice, we examined how exposure to a persistently aversive environment, induced by the application of chronic restraint stress, altered the cortical remodeling post-stroke. We focused on systematically investigating changes in the key components of the neurovascular unit (i.e. neurons, microglia, astrocytes, and blood vessels) within the peri-infarct territories using both immunohistochemistry and Western blotting. The results from our study indicated that exposure to chronic stress exerted a significant suppressive effect on each of the key cellular components involved in neurovascular remodeling. Co-incident with these cellular changes, we observed that chronic stress was associated with an exacerbation of motor impairment 42 days post-event. Collectively, these results highlight the vulnerability of the peri-infarct neurovascular unit to the negative effects of chronic stress.

Purinergic signaling triggers endfoot high-amplitude Ca2+ signals and causes inversion of neurovascular coupling after subarachnoid hemorrhage

PubMed Central

Pappas, Anthony C; Koide, Masayo

2016-01-01

Neurovascular coupling supports brain metabolism by matching focal increases in neuronal activity with local arteriolar dilation. Previously, we demonstrated that an emergence of spontaneous endfoot high-amplitude Ca2+ signals (eHACSs) caused a pathologic shift in neurovascular coupling from vasodilation to vasoconstriction in brain slices obtained from subarachnoid hemorrhage model animals. Extracellular purine nucleotides (e.g., ATP) can trigger astrocyte Ca2+ oscillations and may be elevated following subarachnoid hemorrhage. Here, the role of purinergic signaling in subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling was examined by imaging parenchymal arteriolar diameter and astrocyte Ca2+ signals in rat brain slices using two-photon fluorescent and infrared-differential interference contrast microscopy. We report that broad-spectrum inhibition of purinergic (P2) receptors using suramin blocked eHACSs and restored vasodilatory neurovascular coupling after subarachnoid hemorrhage. Importantly, eHACSs were also abolished using a cocktail of inhibitors targeting Gq-coupled P2Y receptors. Further, activation of P2Y receptors in brain slices from un-operated animals triggered high-amplitude Ca2+ events resembling eHACSs and disrupted neurovascular coupling. Neither tetrodotoxin nor bafilomycin A1 affected eHACSs suggesting that purine nucleotides are not released by ongoing neurotransmission and/or vesicular release after subarachnoid hemorrhage. These results indicate that purinergic signaling via P2Y receptors contributes to subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling. PMID:27207166

Purinergic signaling triggers endfoot high-amplitude Ca2+ signals and causes inversion of neurovascular coupling after subarachnoid hemorrhage.

PubMed

Pappas, Anthony C; Koide, Masayo; Wellman, George C

2016-11-01

Neurovascular coupling supports brain metabolism by matching focal increases in neuronal activity with local arteriolar dilation. Previously, we demonstrated that an emergence of spontaneous endfoot high-amplitude Ca 2+ signals (eHACSs) caused a pathologic shift in neurovascular coupling from vasodilation to vasoconstriction in brain slices obtained from subarachnoid hemorrhage model animals. Extracellular purine nucleotides (e.g., ATP) can trigger astrocyte Ca 2+ oscillations and may be elevated following subarachnoid hemorrhage. Here, the role of purinergic signaling in subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling was examined by imaging parenchymal arteriolar diameter and astrocyte Ca 2+ signals in rat brain slices using two-photon fluorescent and infrared-differential interference contrast microscopy. We report that broad-spectrum inhibition of purinergic (P2) receptors using suramin blocked eHACSs and restored vasodilatory neurovascular coupling after subarachnoid hemorrhage. Importantly, eHACSs were also abolished using a cocktail of inhibitors targeting G q -coupled P2Y receptors. Further, activation of P2Y receptors in brain slices from un-operated animals triggered high-amplitude Ca 2+ events resembling eHACSs and disrupted neurovascular coupling. Neither tetrodotoxin nor bafilomycin A1 affected eHACSs suggesting that purine nucleotides are not released by ongoing neurotransmission and/or vesicular release after subarachnoid hemorrhage. These results indicate that purinergic signaling via P2Y receptors contributes to subarachnoid hemorrhage-induced eHACSs and inversion of neurovascular coupling. © The Author(s) 2016.

Hydrogen Sulfide Attenuates Neurodegeneration and Neurovascular Dysfunction Induced by Intracerebral Administered Homocysteine in Mice

PubMed Central

Kamat, Pradip K.; Kalani, Anuradha; Givvimani, Srikanth; Sathnur, PB; Tyagi, Suresh C.; Tyagi, Neetu

2014-01-01

High levels of homocysteine (Hcy), known as hyperhomocysteinemia (HHcy) are associated with neurovascular diseases. H2S, a metabolite of Hcy, has a potent anti-oxidant and anti-inflammatory activity; however, the effect of H2S has not been explored in Hcy (IC) induced neurodegeneration and neurovascular dysfunction in mice. Therefore, the present study was designed to explore the neuroprotective role of H2S on Hcy induced neurodegeneration and neurovascular dysfunction. To test this hypothesis we employed wild type (WT) males ages 8–10 weeks, WT+ artificial cerebrospinal fluid (aCSF), WT+ Hcy (0.5μmol/μl) intracerebral injection (I.C., one time only prior to NaHS treatment), WT+Hcy +NaHS (sodium hydrogen sulfide, precursor of H2S, 30 μmol/kg, body weight). NaHS was injected intra-peritoneally (I.P.) once daily for the period of 7 days after the Hcy (IC) injection. Hcy treatment significantly increased MDA, nitrite level, acetylcholinestrase activity, TNFα, IL1β, GFAP, iNOS, eNOS and decreased glutathione level indicating oxidative-nitrosative stress and neuroinflammation as compared to control and aCSF treated groups. Further, increased expression of NSE, S100B and decreased expression of (PSD95, SAP97) synaptic protein indicated neurodegeneration. Brain sections of Hcy treated mice showed damage in the cortical area and periventricular cells. TUNEL positive cells and Fluro Jade-C staining indicated apoptosis and neurodegeneration. The increased expression of MMP9, MMP2 and decreased expression of TIMP-1, TIMP-2, tight junction proteins (ZO1, Occuldin) in Hcy treated group indicate neurovascular remodeling. Interestingly, NaHS treatment significantly attenuated Hcy induced oxidative stress, memory deficit, neurodegeneration, neuroinflammation and cerebrovascular remodeling. The results indicate that H2S is effective in providing protection against neurodegeneration and neurovascular dysfunction. PMID:23912038

"In situ preparation": new surgical procedure indicated for soft-tissue sarcoma of a lower limb in close proximity to major neurovascular structures.

PubMed

Matsumoto, Seiichi; Kawaguchi, Noriyoshi; Manabe, Jun; Matsushita, Yasushi

2002-02-01

When soft-tissue sarcomas occur near neurovascular structures, preoperative images cannot always reveal the accurate relationship between the tumor and these structures. Therefore, in some patients, neurovascular structures are sacrificed unnecessarily. In other patients, neurovascular structures are preserved with an inappropriate margin, followed by local recurrence. The objective of this study was to evaluate a new surgical method, "in situ preparation" (ISP), which enables the preparation of neurovascular bundles and the intraoperative evaluation of the surgical margin without contamination by tumor cells. With this method, additional procedures, including pasteurization, alcohol soaking, and distilled water soaking of the preserved neurovascular bundle can also be performed to preserve the continuity of vessels. Between April 1992 and December 1998, 18 patients with soft-tissue sarcoma were operated on using ISP. The tumor and neurovascular structure were lifted en bloc from the surgical bed and separated from the field by the use of a vinyl sheet. The consistency of the neurovascular structures was preserved. The tissue block could be freely turned around and the neurovascular structure was separated from the block through the nearest approach. The margin between the tumor and neurovascular structure was evaluated, and an additional procedure, such as pasteurization, alcohol soaking or distilled water soaking, was performed, according to the safety of the surgical margin. Only one patient showed recurrence after ISP. Complications after ISP were arterial occlusion in two patients and nerve palsy in three patients. The main cause of these complications was the long period of pasteurization; modified additional procedures could prevent such complications. ISP is a useful method with which to ensure a safe surgical margin and good functional results.

Activation of TRPV4 channels does not mediate inversion of neurovascular coupling after SAH.

PubMed

Koide, Masayo; Wellman, George C

2015-01-01

Neurovascular coupling (NVC) allows increased blood flow to metabolically active neurons and involves the Ca²⁺ -dependent release of vasodilator influences by astrocyte endfeet that encase parenchymal arterioles. We previously reported inversion of NVC from dilation to constriction in brain slices from subarachnoid hemorrhage (SAH) model rats. Corresponding to NVC inversion, there was a marked increase in the amplitude of spontaneous Ca²⁺ oscillations in astrocyte endfeet. Calcium-permeable transient receptor potential vanilloid (TRPV)-4 channels have been reported in astrocyte endfeet, and activators of these channels enhance Ca²⁺ oscillations in healthy animals. Here, we examined the role of TRPV4 channels in the development of high-amplitude spontaneous Ca²⁺ oscillations in astrocyte endfeet and the inversion of neurovascular coupling after SAH. Treatment of brain slices with the TRPV4 channel antagonist, HC-067047 (10 μM), did not alter the amplitude of spontaneous Ca²⁺ oscillations after SAH. In addition, HC-067047 did not inhibit or change SAH-induced inversion of neurovascular coupling. In summary, TRPV4 channels do not appear to be involved in the inversion of neurovascular coupling after SAH. Further studies examining the impact of SAH on additional Ca²⁺ signaling pathways in astrocytes are likely to reveal valuable insights into new therapeutic strategies to advance SAH treatments.

Early neurovascular dysfunction in a transgenic rat model of Alzheimer's disease.

PubMed

Joo, Illsung L; Lai, Aaron Y; Bazzigaluppi, Paolo; Koletar, Margaret M; Dorr, Adrienne; Brown, Mary E; Thomason, Lynsie A M; Sled, John G; McLaurin, JoAnne; Stefanovic, Bojana

2017-04-12

Alzheimer's disease (AD), pathologically characterized by amyloid-β peptide (Aβ) accumulation, neurofibrillary tangle formation, and neurodegeneration, is thought to involve early-onset neurovascular abnormalities. Hitherto studies on AD-associated neurovascular injury have used animal models that exhibit only a subset of AD-like pathologies and demonstrated some Aβ-dependent vascular dysfunction and destabilization of neuronal network. The present work focuses on the early stage of disease progression and uses TgF344-AD rats that recapitulate a broader repertoire of AD-like pathologies to investigate the cerebrovascular and neuronal network functioning using in situ two-photon fluorescence microscopy and laminar array recordings of local field potentials, followed by pathological analyses of vascular wall morphology, tau hyperphosphorylation, and amyloid plaques. Concomitant to widespread amyloid deposition and tau hyperphosphorylation, cerebrovascular reactivity was strongly attenuated in cortical penetrating arterioles and venules of TgF344-AD rats in comparison to those in non-transgenic littermates. Blood flow elevation to hypercapnia was abolished in TgF344-AD rats. Concomitantly, the phase-amplitude coupling of the neuronal network was impaired, evidenced by decreased modulation of theta band phase on gamma band amplitude. These results demonstrate significant neurovascular network dysfunction at an early stage of AD-like pathology. Our study identifies early markers of pathology progression and call for development of combinatorial treatment plans.

Neurovascular abnormalities in brain disorders: highlights with angiogenesis and magnetic resonance imaging studies.

PubMed

Chen, Chiao-Chi V; Chen, Yu-Chen; Hsiao, Han-Yun; Chang, Chen; Chern, Yijuang

2013-07-05

The coupling between neuronal activity and vascular responses is controlled by the neurovascular unit (NVU), which comprises multiple cell types. Many different types of dysfunction in these cells may impair the proper control of vascular responses by the NVU. Magnetic resonance imaging, which is the most powerful tool available to investigate neurovascular structures or functions, will be discussed in the present article in relation to its applications and discoveries. Because aberrant angiogenesis and vascular remodeling have been increasingly reported as being implicated in brain pathogenesis, this review article will refer to this hallmark event when suitable.

Endothelial dysfunction and amyloid-β-induced neurovascular alterations

PubMed Central

Koizumi, Kenzo; Wang, Gang; Park, Laibaik

2015-01-01

Alzheimer's disease (AD) and cerebrovascular diseases share common vascular risk factors that have disastrous effects on cerebrovascular regulation. Endothelial cells, lining inner walls of cerebral blood vessels, form a dynamic interface between the blood and the brain and are critical for the maintenance of neurovascular homeostasis. Accordingly, injury in endothelial cells is regarded as one of the earliest symptoms of impaired vasoregulatory mechanisms. Extracellular buildup of amyloid-β (Aβ) is a central pathogenic factor in AD. Aβ exerts potent detrimental effects on cerebral blood vessels and impairs endothelial structure and function. Recent evidence implicates vascular oxidative stress and activation of the nonselective cationic channel transient receptor potential melastatin (TRPM)-2 on endothelial cells in the mechanisms of Aβ-induced neurovascular dysfunction. Thus, Aβ triggers opening of TRPM2 channels in endothelial cells leading to intracellular Ca2+ overload and vasomotor dysfunction. The cerebrovascular dysfunction may contribute to AD pathogenesis by reducing the cerebral blood supply, leading to increased susceptibility to vascular insufficiency, and by promoting Aβ accumulation. The recent realization that vascular factors contribute to AD pathobiology suggests new targets for the prevention and treatment of this devastating disease. PMID:26328781

Patterned optogenetic modulation of neurovascular and metabolic signals

PubMed Central

Richner, Thomas J; Baumgartner, Ryan; Brodnick, Sarah K; Azimipour, Mehdi; Krugner-Higby, Lisa A; Eliceiri, Kevin W; Williams, Justin C; Pashaie, Ramin

2015-01-01

The hemodynamic and metabolic response of the cortex depends spatially and temporally on the activity of multiple cell types. Optogenetics enables specific cell types to be modulated with high temporal precision and is therefore an emerging method for studying neurovascular and neurometabolic coupling. Going beyond temporal investigations, we developed a microprojection system to apply spatial photostimulus patterns in vivo. We monitored vascular and metabolic fluorescence signals after photostimulation in Thy1-channelrhodopsin-2 mice. Cerebral arteries increased in diameter rapidly after photostimulation, while nearby veins showed a slower smaller response. The amplitude of the arterial response was depended on the area of cortex stimulated. The fluorescence signal emitted at 450/100 nm and excited with ultraviolet is indicative of reduced nicotinamide adenine dinucleotide, an endogenous fluorescent enzyme involved in glycolysis and the citric acid cycle. This fluorescence signal decreased quickly and transiently after optogenetic stimulation, suggesting that glucose metabolism is tightly locked to optogenetic stimulation. To verify optogenetic stimulation of the cortex, we used a transparent substrate microelectrode array to map cortical potentials resulting from optogenetic stimulation. Spatial optogenetic stimulation is a new tool for studying neurovascular and neurometabolic coupling. PMID:25388678

Pericytes of the neurovascular unit: Key functions and signaling pathways

PubMed Central

Sweeney, Melanie D.; Ayyadurai, Shiva; Zlokovic, Berislav V.

2017-01-01

Pericytes are vascular mural cells embedded in the basement membrane of blood microvessels. They extend their processes along capillaries, pre-capillary arterioles, and post-capillary venules. The central nervous system (CNS) pericytes are uniquely positioned within the neurovascular unit between endothelial cells, astrocytes, and neurons. They integrate, coordinate, and process signals from their neighboring cells to generate diverse functional responses that are critical for CNS functions in health and disease including regulation of the blood-brain barrier permeability, angiogenesis, clearance of toxic metabolites, capillary hemodynamic responses, neuroinflammation, and stem cell activity. Here, we examine the key signaling pathways between pericytes and their neighboring endothelial cells, astrocytes, and neurons that control neurovascular functions. We also review the role of pericytes in different CNS disorders including rare monogenic diseases and complex neurological disorders such as Alzheimer's disease and brain tumors. Finally, we discuss directions for future studies. PMID:27227366

Discrete event simulation of patient admissions to a neurovascular unit.

PubMed

Hahn-Goldberg, S; Chow, E; Appel, E; Ko, F T F; Tan, P; Gavin, M B; Ng, T; Abrams, H B; Casaubon, L K; Carter, M W

2014-01-01

Evidence exists that clinical outcomes improve for stroke patients admitted to specialized Stroke Units. The Toronto Western Hospital created a Neurovascular Unit (NVU) using beds from general internal medicine, Neurology and Neurosurgery to care for patients with stroke and acute neurovascular conditions. Using patient-level data for NVU-eligible patients, a discrete event simulation was created to study changes in patient flow and length of stay pre- and post-NVU implementation. Varying patient volumes and resources were tested to determine the ideal number of beds under various conditions. In the first year of operation, the NVU admitted 507 patients, over 66% of NVU-eligible patient volumes. With the introduction of the NVU, length of stay decreased by around 8%. Scenario testing showed that the current level of 20 beds is sufficient for accommodating the current demand and would continue to be sufficient with an increase in demand of up to 20%.

Inherited neurovascular diseases affecting cerebral blood vessels and smooth muscle.

PubMed

Sam, Christine; Li, Fei-Feng; Liu, Shu-Lin

2015-10-01

Neurovascular diseases are among the leading causes of mortality and permanent disability due to stroke, aneurysm, and other cardiovascular complications. Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and Marfan syndrome are two neurovascular disorders that affect smooth muscle cells through accumulation of granule and osmiophilic materials and defective elastic fiber formations respectively. Moyamoya disease, hereditary hemorrhagic telangiectasia (HHT), microcephalic osteodysplastic primordial dwarfism type II (MOPD II), and Fabry's disease are disorders that affect the endothelium cells of blood vessels through occlusion or abnormal development. While much research has been done on mapping out mutations in these diseases, the exact mechanisms are still largely unknown. This paper briefly introduces the pathogenesis, genetics, clinical symptoms, and current methods of treatment of the diseases in the hope that it can help us better understand the mechanism of these diseases and work on ways to develop better diagnosis and treatment.

Control of the neurovascular coupling by nitric oxide-dependent regulation of astrocytic Ca2+ signaling

PubMed Central

Muñoz, Manuel F.; Puebla, Mariela; Figueroa, Xavier F.

2015-01-01

Neuronal activity must be tightly coordinated with blood flow to keep proper brain function, which is achieved by a mechanism known as neurovascular coupling. Then, an increase in synaptic activity leads to a dilation of local parenchymal arterioles that matches the enhanced metabolic demand. Neurovascular coupling is orchestrated by astrocytes. These glial cells are located between neurons and the microvasculature, with the astrocytic endfeet ensheathing the vessels, which allows fine intercellular communication. The neurotransmitters released during neuronal activity reach astrocytic receptors and trigger a Ca2+ signaling that propagates to the endfeet, activating the release of vasoactive factors and arteriolar dilation. The astrocyte Ca2+ signaling is coordinated by gap junction channels and hemichannels formed by connexins (Cx43 and Cx30) and channels formed by pannexins (Panx-1). The neuronal activity-initiated Ca2+ waves are propagated among neighboring astrocytes directly via gap junctions or through ATP release via connexin hemichannels or pannexin channels. In addition, Ca2+ entry via connexin hemichannels or pannexin channels may participate in the regulation of the astrocyte signaling-mediated neurovascular coupling. Interestingly, nitric oxide (NO) can activate connexin hemichannel by S-nitrosylation and the Ca2+-dependent NO-synthesizing enzymes endothelial NO synthase (eNOS) and neuronal NOS (nNOS) are expressed in astrocytes. Therefore, the astrocytic Ca2+ signaling triggered in neurovascular coupling may activate NO production, which, in turn, may lead to Ca2+ influx through hemichannel activation. Furthermore, NO release from the hemichannels located at astrocytic endfeet may contribute to the vasodilation of parenchymal arterioles. In this review, we discuss the mechanisms involved in the regulation of the astrocytic Ca2+ signaling that mediates neurovascular coupling, with a special emphasis in the possible participation of NO in this process

Low-energy Shock Wave Therapy Ameliorates Erectile Dysfunction in a Pelvic Neurovascular Injuries Rat Model.

PubMed

Li, Huixi; Matheu, Melanie P; Sun, Fionna; Wang, Lin; Sanford, Melissa T; Ning, Hongxiu; Banie, Lia; Lee, Yung-Chin; Xin, Zhongcheng; Guo, Yinglu; Lin, Guiting; Lue, Tom F

2016-01-01

Erectile dysfunction (ED) caused by pelvic injuries is a common complication of civil and battlefield trauma with multiple neurovascular factors involved, and no effective therapeutic approach is available. To test the effect and mechanisms of low-energy shock wave (LESW) therapy in a rat ED model induced by pelvic neurovascular injuries. Thirty-two male Sprague-Dawley rats injected with 5-ethynyl-2'-deoxyuridine (EdU) at newborn were divided into 4 groups: sham surgery (Sham), pelvic neurovascular injury by bilateral cavernous nerve injury and internal pudendal bundle injury (PVNI), PVNI treated with LESW at low energy (Low), and PVNI treated with LESW at high energy (High). After LESW treatment, rats underwent erectile function measurement and the tissues were harvested for histologic and molecular study. To examine the effect of LESW on Schwann cells, in vitro studies were conducted. The intracavernous pressure (ICP) measurement, histological examination, and Western blot (WB) were conducted. Cell cycle, Schwann cell activation-related markers were examined in in vitro experiments. LESW treatment improves erectile function in a rat model of pelvic neurovascular injury by leading to angiogenesis, tissue restoration, and nerve generation with more endogenous EdU(+) progenitor cells recruited to the damaged area and activation of Schwann cells. LESW facilitates more complete re-innervation of penile tissue with regeneration of neuronal nitric oxide synthase (nNOS)-positive nerves from the MPG to the penis. In vitro experiments demonstrated that LESW has a direct effect on Schwann cell proliferation. Schwann cell activation-related markers including p-Erk1/2 and p75 were upregulated after LESW treatment. LESW-induced endogenous progenitor cell recruitment and Schwann cell activation coincides with angiogenesis, tissue, and nerve generation in a rat model of pelvic neurovascular injuries. Copyright © 2016 International Society for Sexual Medicine. Published by

Persistent increase in oxygen consumption and impaired neurovascular coupling after spreading depression in rat neocortex.

PubMed

Piilgaard, Henning; Lauritzen, Martin

2009-09-01

Cortical spreading depression (CSD) is associated with a dramatic failure of brain ion homeostasis and increased energy metabolism. There is strong clinical and experimental evidence to suggest that CSD is the mechanism of migraine, and involved in progressive neuronal injury in stroke and head trauma. Here we tested the hypothesis that single episodes of CSD induced acute hypoxia, and prolonged impairment of neurovascular and neurometabolic coupling. Cortical spreading depression was induced in rat frontal cortex, whereas cortical electrical activity and local field potentials (LFPs) were recorded by glass microelectrodes, cerebral blood flow (CBF) by laser-Doppler flowmetry, and tissue oxygen tension (tpO(2)) with polarographic microelectrodes. Cortical spreading depression increased cerebral metabolic rate of oxygen (CMRO(2)) by 71%+/-6.7% and CBF by 238%+/-48.1% for 1 to 2 mins. For the following 2 h, basal tpO(2) and CBF were reduced whereas basal CMRO(2) was persistently elevated by 8.1%+/-2.9%. In addition, within first hour after CSD we found impaired neurovascular coupling (LFP versus CBF), whereas neurometabolic coupling (LFP versus CMRO(2)) remained unaffected. Impaired neurovascular coupling was explained by both reduced vascular reactivity and suppressed function of cortical inhibitory interneurons. The protracted effects of CSD on basal CMRO(2) and neurovascular coupling may contribute to cellular dysfunction in patients with migraine and acutely injured cerebral cortex.

Human Albumin Improves Long-Term Behavioral Sequelae After Subarachnoid Hemorrhage Through Neurovascular Remodeling.

PubMed

Xie, Yi; Liu, Wenhua; Zhang, Xiaohao; Wang, Liumin; Xu, Lili; Xiong, Yunyun; Yang, Lian; Sang, Hongfei; Ye, Ruidong; Liu, Xinfeng

2015-10-01

Subarachnoid hemorrhage results in significant long-lasting neurologic sequelae. Here, we investigated whether human albumin improves long-term outcomes in experimental subarachnoid hemorrhage and whether neurovascular remodeling is involved in the protection of albumin. Laboratory investigation. Hospital research laboratory. Male Sprague-Dawley rats. Rats underwent subarachnoid hemorrhage by endovascular perforation. Albumin of either 0.63 or 1.25 g/kg was injected IV immediately after the surgery. Modified Garcia test, beam-walking test, novel object recognition, and Morris water maze were employed to determine the behavioral deficits. The effects of albumin on early neurovascular dysfunction and chronic synaptic plasticity were also studied. Both doses of albumin significantly improved the sensorimotor scores (F = 31.277; p = 0.001) and cognitive performance (F = 7.982; p = 0.001 in novel object recognition test; and F = 3.431; p = 0.026 in the latency analysis of Morris water maze test) for at least 40 days after subarachnoid hemorrhage. There were remarkable microvasculature hypoperfusion, intracranial pressure rise, early vasoconstriction, neural apoptosis, and degeneration in subarachnoid hemorrhage rats, with albumin significantly attenuating such neurovascular dysfunction. Furthermore, albumin markedly prevented blood-brain barrier disruption, as indicated by less blood-brain barrier leakage, preserved blood-brain barrier-related proteins, and dampened gelatinase activities. The expressions of key synaptic elements were up-regulated with albumin supplementation in both acute and chronic phases. Accordingly, a higher dendritic spine density was observed in the prefrontal and hippocampal areas of albumin-treated subarachnoid hemorrhage animals. Albumin at low-to-moderate doses markedly improves long-term neurobehavioral sequelae after subarachnoid hemorrhage, which may involve an integrated process of neurovascular remodeling.

The hypothalamic neuropeptide oxytocin is required for formation of the neurovascular interface of the pituitary.

PubMed

Gutnick, Amos; Blechman, Janna; Kaslin, Jan; Herwig, Lukas; Belting, Heinz-Georg; Affolter, Markus; Bonkowsky, Joshua L; Levkowitz, Gil

2011-10-18

The hypothalamo-neurohypophyseal system (HNS) is the neurovascular structure through which the hypothalamic neuropeptides oxytocin and arginine-vasopressin exit the brain into the bloodstream, where they go on to affect peripheral physiology. Here, we investigate the molecular cues that regulate the neurovascular contact between hypothalamic axons and neurohypophyseal capillaries of the zebrafish. We developed a transgenic system in which both hypothalamic axons and neurohypophyseal vasculature can be analyzed in vivo. We identified the cellular organization of the zebrafish HNS as well as the dynamic processes that contribute to formation of the HNS neurovascular interface. We show that formation of this interface is regulated during development by local release of oxytocin, which affects endothelial morphogenesis. This cell communication process is essential for the establishment of a tight axovasal interface between the neurons and blood vessels of the HNS. We present a unique example of axons affecting endothelial morphogenesis through secretion of a neuropeptide. Copyright © 2011 Elsevier Inc. All rights reserved.

Neurovascular Alterations in Alzheimer's Disease: Transporter Expression Profiles and CNS Drug Access.

PubMed

McInerney, Mitchell P; Short, Jennifer L; Nicolazzo, Joseph A

2017-07-01

Despite a century of steady and incremental progress toward understanding the underlying biochemical mechanisms, Alzheimer's disease (AD) remains a complicated and enigmatic disease, and greater insight will be necessary before substantive clinical success is realised. Over the last decade in particular, a large body of work has highlighted the cerebral microvasculature as an anatomical region with an increasingly apparent role in the pathogenesis of AD. The causative interplay and temporal cascade that manifest between the brain vasculature and the wider disease progression of AD are not yet fully understood, and further inquiry is required to properly characterise these relationships. The purpose of this review is to highlight the recent advancements in research implicating neurovascular factors in AD, at both the molecular and anatomical levels. We begin with a brief introduction of the biochemical and genetic aspects of AD, before reviewing the essential concepts of the blood-brain barrier (BBB) and the neurovascular unit (NVU). In detail, we then examine the evidence demonstrating involvement of BBB dysfunction in AD pathogenesis, highlighting the importance of neurovascular components in AD. Lastly, we include within this review research that focuses on how altered properties of the BBB in AD impact upon CNS exposure of therapeutic agents and the potential clinical impact that this may have on people with this disease.

Early neurovascular dysfunction in a transgenic rat model of Alzheimer’s disease

PubMed Central

Joo, Illsung L.; Lai, Aaron Y.; Bazzigaluppi, Paolo; Koletar, Margaret M.; Dorr, Adrienne; Brown, Mary E.; Thomason, Lynsie A. M.; Sled, John G.; McLaurin, JoAnne; Stefanovic, Bojana

2017-01-01

Alzheimer’s disease (AD), pathologically characterized by amyloid-β peptide (Aβ) accumulation, neurofibrillary tangle formation, and neurodegeneration, is thought to involve early-onset neurovascular abnormalities. Hitherto studies on AD-associated neurovascular injury have used animal models that exhibit only a subset of AD-like pathologies and demonstrated some Aβ-dependent vascular dysfunction and destabilization of neuronal network. The present work focuses on the early stage of disease progression and uses TgF344-AD rats that recapitulate a broader repertoire of AD-like pathologies to investigate the cerebrovascular and neuronal network functioning using in situ two-photon fluorescence microscopy and laminar array recordings of local field potentials, followed by pathological analyses of vascular wall morphology, tau hyperphosphorylation, and amyloid plaques. Concomitant to widespread amyloid deposition and tau hyperphosphorylation, cerebrovascular reactivity was strongly attenuated in cortical penetrating arterioles and venules of TgF344-AD rats in comparison to those in non-transgenic littermates. Blood flow elevation to hypercapnia was abolished in TgF344-AD rats. Concomitantly, the phase-amplitude coupling of the neuronal network was impaired, evidenced by decreased modulation of theta band phase on gamma band amplitude. These results demonstrate significant neurovascular network dysfunction at an early stage of AD-like pathology. Our study identifies early markers of pathology progression and call for development of combinatorial treatment plans. PMID:28401931

Neurovascular and Immuno-Imaging: From Mechanisms to Therapies. Proceedings of the Inaugural Symposium

PubMed Central

Akassoglou, Katerina; Agalliu, Dritan; Chang, Christopher J.; Davalos, Dimitrios; Grutzendler, Jaime; Hillman, Elizabeth M. C.; Khakh, Baljit S.; Kleinfeld, David; McGavern, Dorian B.; Nelson, Sarah J.; Zlokovic, Berislav V.

2016-01-01

Breakthrough advances in intravital imaging have launched a new era for the study of dynamic interactions at the neurovascular interface in health and disease. The first Neurovascular and Immuno-Imaging Symposium was held at the Gladstone Institutes, University of California, San Francisco in March, 2015. This highly interactive symposium brought together a group of leading researchers who discussed how recent studies have unraveled fundamental biological mechanisms in diverse scientific fields such as neuroscience, immunology, and vascular biology, both under physiological and pathological conditions. These Proceedings highlight how advances in imaging technologies and their applications revolutionized our understanding of the communication between brain, immune, and vascular systems and identified novel targets for therapeutic intervention in neurological diseases. PMID:26941593

Early disrupted neurovascular coupling and changed event level hemodynamic response function in type 2 diabetes: an fMRI study.

PubMed

Duarte, João V; Pereira, João M S; Quendera, Bruno; Raimundo, Miguel; Moreno, Carolina; Gomes, Leonor; Carrilho, Francisco; Castelo-Branco, Miguel

2015-10-01

Type 2 diabetes (T2DM) patients develop vascular complications and have increased risk for neurophysiological impairment. Vascular pathophysiology may alter the blood flow regulation in cerebral microvasculature, affecting neurovascular coupling. Reduced fMRI signal can result from decreased neuronal activation or disrupted neurovascular coupling. The uncertainty about pathophysiological mechanisms (neurodegenerative, vascular, or both) underlying brain function impairments remains. In this cross-sectional study, we investigated if the hemodynamic response function (HRF) in lesion-free brains of patients is altered by measuring BOLD (Blood Oxygenation Level-Dependent) response to visual motion stimuli. We used a standard block design to examine the BOLD response and an event-related deconvolution approach. Importantly, the latter allowed for the first time to directly extract the true shape of HRF without any assumption and probe neurovascular coupling, using performance-matched stimuli. We discovered a change in HRF in early stages of diabetes. T2DM patients show significantly different fMRI response profiles. Our visual paradigm therefore demonstrated impaired neurovascular coupling in intact brain tissue. This implies that functional studies in T2DM require the definition of HRF, only achievable with deconvolution in event-related experiments. Further investigation of the mechanisms underlying impaired neurovascular coupling is needed to understand and potentially prevent the progression of brain function decrements in diabetes.

Simultaneous functional photoacoustic microscopy and electrocorticography reveal the impact of rtPA on dynamic neurovascular functions after cerebral ischemia.

PubMed

Bandla, Aishwarya; Liao, Lun-De; Chan, Su Jing; Ling, Ji Min; Liu, Yu-Hang; Shih, Yen-Yu Ian; Pan, Han-Chi; Wong, Peter Tsun-Hon; Lai, Hsin-Yi; King, Nicolas Kon Kam; Chen, You-Yin; Ng, Wai Hoe; Thakor, Nitish V

2018-06-01

The advance of thrombolytic therapy has been hampered by the lack of optimization of the therapy during the hyperacute phase of focal ischemia. Here, we investigate neurovascular dynamics using a custom-designed hybrid electrocorticography (ECoG)-functional photoacoustic microscopy (fPAM) imaging system during the hyperacute phase (first 6 h) of photothrombotic ischemia (PTI) in male Wistar rats following recombinant tissue plasminogen activator (rtPA)-mediated thrombolysis. We reported, for the first time, the changes in neural activity and cerebral hemodynamic responses following rtPA infusion at different time points post PTI. Interestingly, very early administration of rtPA (< 1 h post PTI) resulted in only partial recovery of neurovascular dynamics (specifically , neural activity recovered to 71 ± 3.5% of baseline and hemodynamics to only 52 ± 2.6% of baseline) and late administration of rtPA (> 4 h post PTI) resulted in the deterioration of neurovascular function. A therapeutic window between 1 and 3 h post PTI was found to improve recovery of neurovascular function (i.e. significant restoration of neural activity to 93 ± 4.2% of baseline and hemodynamics to 81 ± 2.1% of baseline, respectively). The novel combination of fPAM and ECoG enables direct mapping of neurovascular dynamics and serves as a platform to evaluate potential interventions for stroke.

Neurovascular compression of the trigeminal and glossopharyngeal nerve: three case reports

PubMed Central

Childs, A; Meaney, J; Ferrie, C; Holland, P

2000-01-01

Trigeminal neuralgia (TN) is a frequent cause of paroxysmal facial pain and headache in adults. Glossopharyngeal neuralgia (GPN) is less common, but can cause severe episodic pain in the ear and throat. Neurovascular compression of the appropriate cranial nerve as it leaves the brain stem is responsible for the symptoms in many patients, and neurosurgical decompression of the nerve is now a well accepted treatment in adults with both TN and GPN who fail to respond to drug therapy. Neither TN nor GPN are routinely considered in the differential diagnosis when assessing children with paroxysmal facial or head pain, as they are not reported to occur in childhood. Case reports of three children with documented neurovascular compression causing severe neuralgic pain and disability are presented. The fact that these conditions do occur in the paediatric population, albeit rarely, is highlighted, and appropriate investigation and management are discussed.

 PMID:10735840

New Wavelet Neurovascular Bundle for Bedside Evaluation of Cerebral Autoregulation and Neurovascular Coupling in Newborns with Hypoxic-Ischemic Encephalopathy.

PubMed

Chalak, Lina F; Zhang, Rong

2017-01-01

Neonatal encephalopathy (NE) resulting from birth asphyxia constitutes a major global public health burden for millions of infants every year, and despite therapeutic hypothermia, half of these neonates have poor neurological outcomes. As new neuroprotective interventions are being studied in clinical trials, there is a critical need to establish physiological surrogate markers of therapeutic efficacy, to guide patient selection and/or to modify the therapeutic intervention. The challenge in the field of neonatal brain injury has been the difficulty of clinically discerning NE severity within the short therapeutic window after birth or of analyzing the dynamic aspects of the cerebral circulation in sick NE newborns. To address this roadblock, we have recently developed a new "wavelet neurovascular bundle" analytical system that can measure cerebral autoregulation (CA) and neurovascular coupling (NVC) at multiple time scales under dynamic, nonstationary clinical conditions. This wavelet analysis may allow noninvasive quantification at the bedside of (1) CA (combining metrics of blood pressure and cerebral near-infrared spectroscopy, NIRS) and (2) NVC (combining metrics obtained from NIRS and EEG) in newborns with encephalopathy without mathematical assumptions of linear and stationary systems. In this concept paper, we present case examples of NE using the proposed physiological wavelet metrics of CA and NVC. The new approach, once validated in large NE studies, has the potential to optimize the selection of candidates for therapeutic decision-making, and the prediction of neurocognitive outcomes. © 2017 S. Karger AG, Basel.

New Wavelet Neurovascular Bundle for Bedside Evaluation of Cerebral Autoregulation and Neurovascular Coupling in Newborns with Hypoxic Ischemic Encephalopathy

PubMed Central

Chalak, Lina F; Zhang, Rong

2017-01-01

Neonatal encephalopathy (NE) resulting from birth asphyxia constitutes a major global public health burden for millions of infants every year, and despite therapeutic hypothermia, half of neonates have poor neurologic outcomes. As new neuroprotective interventions are being studied in clinical trials, there is a critical need to establish physiological surrogate markers of therapeutic efficacy, to guide patient selection and/or to modify the therapeutic intervention. The challenge in the field of neonatal brain injury has been the difficulty to clinically discern the NE severity within the short therapeutic window after birth, or to analyze the dynamic aspects of the cerebral circulation in the NE sick newborns. To address this road block, we have recently developed a new “wavelet neurovascular bundle” analytical system that can measure cerebral autoregulation (CA) and neurovascular coupling (NVC) at multiple time scales under dynamic, non-stationary clinical conditions. This wavelet analysis can enable non-invasive quantification at the bedside of 1) CA (combining metrics of blood pressure and cerebral NIRS), and 2) NVC (combining metrics obtained from NIRS and EEG) in newborns with encephalopathy without mathematical assumptions of linear and stationary systems. In this concept paper, we present case examples of NE using the proposed physiological wavelet metrics of CA and NVC. The new approach, once validated in large NE studies has the potential to optimize the selection of candidates for therapeutic decision making, and the prediction of neurocognitive outcomes. PMID:28355608

Ultrasonographic evaluation of displaced neurovascular bundle in Dupuytren disease.

PubMed

Uehara, Kosuke; Miura, Toshiki; Morizaki, Yutaka; Miyamoto, Hideaki; Ohe, Takashi; Tanaka, Sakae

2013-01-01

Neurovascular injury is a serious complication after surgery for Dupuytren disease. The purpose of this study was to evaluate the relationship between the cord and the neurovascular bundle ultrasonographically. We included 22 healthy volunteers and 14 Dupuytren disease patients (25 fingers) in this study. We evaluated the cord and the digital artery with high-resolution ultrasound. We first investigated the effect of the angle of metacarpophalangeal joint on the position of the radial and ulnar digital arteries in volunteers without evidence of Dupuytren disease. We compared 3 parameters of the radial and ulnar digital arteries, including differences in depth, differences in lateral shift, and the shape of the cross-section of the artery, between volunteers and patients with Dupuytren disease. None of these parameters changed with flexion of the metacarpophalangeal joint of 0°, 30°, and 60°. Digital arteries and cords could be identified ultrasonographically in all patients, and we confirmed ultrasonographic findings by operative findings in 13 fingers. We classified the fingers into 3 subgroups based on the ultrasonographic findings: type A (n = 13), in which the cord was above the artery; type B (n = 5), in which the cord was below the artery; and type C (n = 7), in which the cord was located between the radial and ulnar digital arteries. Types A, B, and C corresponded to natatory cord/abductor digiti minimi cord, spiral cord, and central cord, respectively. Comparisons among volunteers and patient subgroups showed that the difference in depth in type B patients was significantly larger than that of the other groups. When we set the cutoff point of the difference in depth to 3 mm, sensitivity and specificity to detect the spiral cord were 80% and 76%, respectively. The relationship between the neurovascular bundle and the type of Dupuytren disease cord can be evaluated by high-resolution ultrasound. Diagnostic III. Copyright © 2013 American Society for

Toward the Era of a One-Stop Imaging Service Using an Angiography Suite for Neurovascular Disorders

PubMed Central

Hung, Sheng-Che; Lin, Chung-Jung; Chang, Feng-Chi; Luo, Chao-Bao; Teng, Michael Mu-Huo; Chang, Cheng-Yen

2013-01-01

Transportation of patients requiring multiple diagnostic and imaging-guided therapeutic modalities is unavoidable in current radiological practice. This clinical scenario causes time delays and increased risk in the management of stroke and other neurovascular emergencies. Since the emergence of flat-detector technology in imaging practice in recent decades, studies have proven that flat-detector X-ray angiography in conjunction with contrast medium injection and specialized reconstruction algorithms can provide not only high-quality and high-resolution CT-like images but also functional information. This improvement in imaging technology allows quantitative assessment of intracranial hemodynamics and, subsequently in the same imaging session, provides treatment guidance for patients with neurovascular disorders by using only a flat-detector angiographic suite—a so-called one-stop quantitative imaging service (OSIS). In this paper, we review the recent developments in the field of flat-detector imaging and share our experience of applying this technology in neurovascular disorders such as acute ischemic stroke, cerebral aneurysm, and stenoocclusive carotid diseases. PMID:23762863

Anatomical Evaluation of the Proximity of Neurovascular Structures During Arthroscopically Assisted Acromioclavicular Joint Reconstruction: A Cadaveric Pilot Study.

PubMed

Banaszek, Daniel; Pickell, Michael; Wilson, Evan; Ducsharm, Melissa; Hesse, Daniel; Easteal, Ron; Bardana, Davide D

2017-01-01

The purpose of this study was to examine the safety of an arthroscopic technique for acromioclavicular joint (ACJ) reconstruction by investigating its proximity to important neurovascular structures. Six shoulders from 4 cadaveric specimens were used for ACJ reconstruction in this study. The procedure consists of performing an arthroscopic acromioclavicular (AC) reduction with a double button construct, followed by coracoclavicular ligament reconstruction without drilling clavicular tunnels. Shoulders were subsequently dissected in order to identify and measure distances to adjacent neurovascular structures. The suprascapular artery and nerve were the closest neurovascular structures to implanted materials. The mean distances were 8.2 (standard deviation [SD] = 3.6) mm to the suprascapular nerve and 5.6 (SD = 4.2) mm to the suprascapular artery. The mean distance of the suprascapular nerve from implants was found to be greater than 5 mm (P = .040), while the distance to the suprascapular artery was not (P > .5). Neither difference was statistically significant (P = .80 for artery; P = .08 for nerve). Mini-open, arthroscopically assisted ACJ reconstruction safely avoids the surrounding nerves, with no observed damage to any neurovascular structures including the suprascapular nerve and artery, and may be a viable alternative to open techniques. However, surgeons must remain cognizant of possible close proximity to the suprascapular artery. This study represents an evaluation of the safety and feasibility of a minimally invasive ACJ reconstruction as it relates to the proximity of neurovascular structures. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Neurovascular and Neuroimmune Aspects in the Pathophysiology of Rosacea

PubMed Central

Schwab, Verena D.; Sulk, Mathias; Seeliger, Stephan; Nowak, Pawel; Aubert, Jerome; Mess, Christian; Rivier, Michel; Carlavan, Isabelle; Rossio, Patricia; Metze, Dieter; Buddenkotte, Jörg; Cevikbas, Ferda; Voegel, Johannes J.; Steinhoff, Martin

2013-01-01

Rosacea is a common skin disease with a high impact on quality of life. Characterized by erythema, edema, burning pain, immune infiltration, and facial skin fibrosis, rosacea has all the characteristics of neurogenic inflammation, a condition induced by sensory nerves via antidromically released neuromediators. To investigate the hypothesis of a central role of neural interactions in the pathophysiology, we analyzed molecular and morphological characteristics in the different subtypes of rosacea by immunohistochemistry, double immunofluorescence, morphometry, real-time PCR, and gene array analysis, and compared the findings with those for lupus erythematosus or healthy skin. Our results showed significantly dilated blood and lymphatic vessels. Signs of angiogenesis were only evident in phymatous rosacea. The number of mast cells and fibroblasts was increased in rosacea, already in subtypes in which fibrosis is not clinically apparent, indicating early activation. Sensory nerves were closely associated with blood vessels and mast cells, and were increased in erythematous rosacea. Gene array studies and qRT-PCR confirmed upregulation of genes involved in vasoregulation and neurogenic inflammation. Thus, dysregulation of mediators and receptors implicated in neurovascular and neuroimmune communication may be crucial at early stages of rosacea. Drugs that function on neurovascular and/or neuroimmune communication may be beneficial for the treatment of rosacea. PMID:22076328

Microvascular decompression or neuromodulation in patients with SUNCT and trigeminal neurovascular conflict?

PubMed

Hassan, Samih; Lagrata, Susie; Levy, Andrew; Matharu, Manjit; Zrinzo, Ludvic

2018-02-01

Objectives To assess the effectiveness of neuromodulation and trigeminal microvascular decompression (MVD) in patients with medically-intractable short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT). Methods Two patients with medically refractory SUNCT underwent MVD following beneficial but incomplete response to neuromodulation (occipital nerve stimulation and deep brain stimulation). MRI confirmed neurovascular conflict with the ipsilateral trigeminal nerve in both patients. Results Although neuromodulation provided significant benefit, it did not deliver complete relief from pain and management required numerous postoperative visits with adjustment of medication and stimulation parameters. Conversely, MVD was successful in eliminating symptoms of SUNCT in both patients with no need for further medical treatment or neuromodulation. Conclusion Neuromodulation requires expensive hardware and lifelong follow-up and maintenance. These case reports highlight that microvascular decompression may be preferable to neuromodulation in the subset of SUNCT patients with ipsilateral neurovascular conflict.

MRI Markers of Neurodegenerative and Neurovascular Changes in Relation to Postoperative Delirium and Postoperative Cognitive Decline.

PubMed

Kant, Ilse M J; de Bresser, Jeroen; van Montfort, Simone J T; Slooter, Arjen J C; Hendrikse, Jeroen

2017-10-01

Postoperative delirium (POD) and postoperative cognitive decline (POCD) are common in elderly patients. The aim of the present review was to explore the association of neurodegenerative and neurovascular changes with the occurrence of POD and POCD. Fifteen MRI studies were identified by combining multiple search terms for POD, POCD, and brain imaging. These studies described a total of 1,422 patients and were all observational in design. Neurodegenerative changes (global and regional brain volumes) did not show a consistent association with the occurrence of POD (four studies) or POCD (two studies). In contrast, neurovascular changes (white matter hyperintensities and cerebral infarcts) were more consistently associated with the occurrence of POD (seven studies) and POCD (five studies). In conclusion, neurovascular changes appear to be consistently associated with the occurrence of POD and POCD, and may identify patients at increased risk of these conditions. Larger prospective studies are needed to study the consistency of these findings and to unravel the underlying pathophysiological mechanisms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

TRPV4 channels stimulate Ca2+-induced Ca2+ release in astrocytic endfeet and amplify neurovascular coupling responses.

PubMed

Dunn, Kathryn M; Hill-Eubanks, David C; Liedtke, Wolfgang B; Nelson, Mark T

2013-04-09

In the CNS, astrocytes are sensory and regulatory hubs that play important roles in cerebral homeostatic processes, including matching local cerebral blood flow to neuronal metabolism (neurovascular coupling). These cells possess a highly branched network of processes that project from the soma to neuronal synapses as well as to arterioles and capillaries, where they terminate in "endfeet" that encase the blood vessels. Ca(2+) signaling within the endfoot mediates neurovascular coupling; thus, these functional microdomains control vascular tone and local perfusion in the brain. Transient receptor potential vanilloid 4 (TRPV4) channels--nonselective cation channels with considerable Ca(2+) conductance--have been identified in astrocytes, but their function is largely unknown. We sought to characterize the influence of TRPV4 channels on Ca(2+) dynamics in the astrocytic endfoot microdomain and assess their role in neurovascular coupling. We identified local TRPV4-mediated Ca(2+) oscillations in endfeet and further found that TRPV4 Ca(2+) signals are amplified and propagated by Ca(2+)-induced Ca(2+) release from inositol trisphosphate receptors (IP3Rs). Moreover, TRPV4-mediated Ca(2+) influx contributes to the endfoot Ca(2+) response to neuronal activation, enhancing the accompanying vasodilation. Our results identify a dynamic synergy between TRPV4 channels and IP3Rs in astrocyte endfeet and demonstrate that TRPV4 channels are engaged in and contribute to neurovascular coupling.

Acute neurovascular events in cancer patients receiving anti-vascular endothelial growth factor agents: Clinical experience in Paris University Hospitals.

PubMed

Tlemsani, Camille; Mir, Olivier; Psimaras, Dimitri; Vano, Yann-Alexandre; Ducreux, Michel; Escudier, Bernard; Rousseau, Benoit; Loirat, Delphine; Ceccaldi, Bernard; André, Thierry; Goldwasser, François; Ricard, Damien

2016-10-01

Despite the increasing and broadening use of agents targeting the vascular endothelial growth factor (VEGF) pathway, little is known on their acute neurovascular toxicities. This retrospective, multi-centre study examined the characteristics of patients with solid tumours who experienced an ischaemic or haemorrhagic stroke, a transient ischaemic accident (TIA) or a posterior reversible encephalopathy syndrome (PRES) while under anti-VEGF and until 8 weeks after termination of treatment and evaluated their management in our institutions from 2004 to 2014. Patients with newly diagnosed or progressive cerebral metastases at the time of the acute neurovascular event were excluded. Thirty-four patients (55.9% men) were identified, and experienced either ischaemic stroke (n = 18), PRES (n = 9), TIA (n = 6) or haemorrhagic stroke (n = 1). At initiation of anti-VEGF agents, 64.7% of patients had previous cardiovascular risk factors, and 52.9% had hypertension. Eight patients (23.5%) had received cerebral radiotherapy, five of which concomitantly to anti-VEGF treatment. Six (17%) patients died in the 8 weeks following the acute neurovascular event, and only 55.9% recovered their initial neurological status. Overall, 1-year and 2-year survival rates after the acute neurovascular event were 67.9% and 50%, respectively. When anti-VEGF agents were reintroduced (n = 6), severe vascular toxicity recurred in two patients. Neurovascular events under VEGF treatments are potentially severe, and the management of comorbid conditions has to be improved. A prospective collection of data and standardised management of such events is therefore being structured in our institutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

The tissue-type plasminogen activator–plasminogen activator inhibitor 1 complex promotes neurovascular injury in brain trauma: evidence from mice and humans

PubMed Central

Sashindranath, Maithili; Sales, Eunice; Daglas, Maria; Freeman, Roxann; Samson, Andre L.; Cops, Elisa J.; Beckham, Simone; Galle, Adam; McLean, Catriona; Morganti-Kossmann, Cristina; Rosenfeld, Jeffrey V.; Madani, Rime; Vassalli, Jean-Dominique; Su, Enming J.; Lawrence, Daniel A.

2012-01-01

The neurovascular unit provides a dynamic interface between the circulation and central nervous system. Disruption of neurovascular integrity occurs in numerous brain pathologies including neurotrauma and ischaemic stroke. Tissue plasminogen activator is a serine protease that converts plasminogen to plasmin, a protease that dissolves blood clots. Besides its role in fibrinolysis, tissue plasminogen activator is abundantly expressed in the brain where it mediates extracellular proteolysis. However, proteolytically active tissue plasminogen activator also promotes neurovascular disruption after ischaemic stroke; the molecular mechanisms of this process are still unclear. Tissue plasminogen activator is naturally inhibited by serine protease inhibitors (serpins): plasminogen activator inhibitor-1, neuroserpin or protease nexin-1 that results in the formation of serpin:protease complexes. Proteases and serpin:protease complexes are cleared through high-affinity binding to low-density lipoprotein receptors, but their binding to these receptors can also transmit extracellular signals across the plasma membrane. The matrix metalloproteinases are the second major proteolytic system in the mammalian brain, and like tissue plasminogen activators are pivotal to neurological function but can also degrade structures of the neurovascular unit after injury. Herein, we show that tissue plasminogen activator potentiates neurovascular damage in a dose-dependent manner in a mouse model of neurotrauma. Surprisingly, inhibition of activity following administration of plasminogen activator inhibitor-1 significantly increased cerebrovascular permeability. This led to our finding that formation of complexes between tissue plasminogen activator and plasminogen activator inhibitor-1 in the brain parenchyma facilitates post-traumatic cerebrovascular damage. We demonstrate that following trauma, the complex binds to low-density lipoprotein receptors, triggering the induction of matrix

Neurovascular-neuroenergetic coupling axis in the brain: master regulation by nitric oxide and consequences in aging and neurodegeneration.

PubMed

Lourenço, Cátia F; Ledo, Ana; Barbosa, Rui M; Laranjinha, João

2017-07-01

The strict energetic demands of the brain require that nutrient supply and usage be fine-tuned in accordance with the specific temporal and spatial patterns of ever-changing levels of neuronal activity. This is achieved by adjusting local cerebral blood flow (CBF) as a function of activity level - neurovascular coupling - and by changing how energy substrates are metabolized and shuttled amongst astrocytes and neurons - neuroenergetic coupling. Both activity-dependent increase of CBF and O 2 and glucose utilization by active neural cells are inextricably linked, establishing a functional metabolic axis in the brain, the neurovascular-neuroenergetic coupling axis. This axis incorporates and links previously independent processes that need to be coordinated in the normal brain. We here review evidence supporting the role of neuronal-derived nitric oxide ( • NO) as the master regulator of this axis. Nitric oxide is produced in tight association with glutamatergic activation and, diffusing several cell diameters, may interact with different molecular targets within each cell type. Hemeproteins such as soluble guanylate cyclase, cytochrome c oxidase and hemoglobin, with which • NO reacts at relatively fast rates, are but a few of the key in determinants of the regulatory role of • NO in the neurovascular-neuroenergetic coupling axis. Accordingly, critical literature supporting this concept is discussed. Moreover, in view of the controversy regarding the regulation of catabolism of different neural cells, we further discuss key aspects of the pathways through which • NO specifically up-regulates glycolysis in astrocytes, supporting lactate shuttling to neurons for oxidative breakdown. From a biomedical viewpoint, derailment of neurovascular-neuroenergetic axis is precociously linked to aberrant brain aging, cognitive impairment and neurodegeneration. Thus, we summarize current knowledge of how both neurovascular and neuroenergetic coupling are compromised in

Neurophysiological, metabolic and cellular compartments that drive neurovascular coupling and neuroimaging signals

PubMed Central

Moreno, Andrea; Jego, Pierrick; de la Cruz, Feliberto; Canals, Santiago

2013-01-01

Complete understanding of the mechanisms that coordinate work and energy supply of the brain, the so called neurovascular coupling, is fundamental to interpreting brain energetics and their influence on neuronal coding strategies, but also to interpreting signals obtained from brain imaging techniques such as functional magnetic resonance imaging. Interactions between neuronal activity and cerebral blood flow regulation are largely compartmentalized. First, there exists a functional compartmentalization in which glutamatergic peri-synaptic activity and its electrophysiological events occur in close proximity to vascular responses. Second, the metabolic processes that fuel peri-synaptic activity are partially segregated between glycolytic and oxidative compartments. Finally, there is cellular segregation between astrocytic and neuronal compartments, which has potentially important implications on neurovascular coupling. Experimental data is progressively showing a tight interaction between the products of energy consumption and neurotransmission-driven signaling molecules that regulate blood flow. Here, we review some of these issues in light of recent findings with special attention to the neuron-glia interplay on the generation of neuroimaging signals. PMID:23543907

Role of pattern recognition receptors of the neurovascular unit in inflamm-aging.

PubMed

Wilhelm, Imola; Nyúl-Tóth, Ádám; Kozma, Mihály; Farkas, Attila E; Krizbai, István A

2017-11-01

Aging is associated with chronic inflammation partly mediated by increased levels of damage-associated molecular patterns, which activate pattern recognition receptors (PRRs) of the innate immune system. Furthermore, many aging-related disorders are associated with inflammation. PRRs, such as Toll-like receptors (TLRs) and nucleotide-binding oligomerization domain-like receptors (NLRs), are expressed not only in cells of the innate immune system but also in other cells, including cells of the neurovascular unit and cerebral vasculature forming the blood-brain barrier. In this review, we summarize our present knowledge about the relationship between activation of PRRs expressed by cells of the neurovascular unit-blood-brain barrier, chronic inflammation, and aging-related pathologies of the brain. The most important damage-associated molecular pattern-sensing PRRs in the brain are TLR2, TLR4, and NLR family pyrin domain-containing protein-1 and pyrin domain-containing protein-3, which are activated during physiological and pathological aging in microglia, neurons, astrocytes, and possibly endothelial cells and pericytes. Copyright © 2017 the American Physiological Society.

Pathophysiological implications of neurovascular P450 in brain disorders

PubMed Central

Ghosh, Chaitali; Hossain, Mohammed; Solanki, Jesal; Dadas, Aaron; Marchi, Nicola; Janigro, Damir

2016-01-01

Over the past decades, the significance of cytochrome P450 (CYP) enzymes has expanded beyond their role as peripheral drug metabolizers in the liver and gut. CYP enzymes are also functionally active at the neurovascular interface. CYP expression is modulated by disease states, impacting cellular functions, detoxification, and reactivity to toxic stimuli and brain drug biotransformation. Unveiling the physiological and molecular complexity of brain P450 enzymes will improve our understanding of the mechanisms underlying brain drug availability, pharmacological efficacy, and neurotoxic adverse effects from pharmacotherapy targeting brain disorders. PMID:27312874

Anatomy of Mandibular Vital Structures. Part I: Mandibular Canal and Inferior Alveolar Neurovascular Bundle in Relation with Dental Implantology

PubMed Central

Wang, Hom-Lay; Sabalys, Gintautas

2010-01-01

ABSTRACT Objectives It is critical to determine the location and configuration of the mandibular canal and related vital structures during the implant treatment. The purpose of the present study was to review the literature concerning the mandibular canal and inferior alveolar neurovascular bundle anatomical variations related to the implant surgery. Material and Methods Literature was selected through the search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular canal, inferior alveolar nerve, and inferior alveolar neurovascular bundle. The search was restricted to English language articles, published from 1973 to November 2009. Additionally, a manual search in the major anatomy, dental implant, prosthetic and periodontal journals and books were performed. Results In total, 46 literature sources were obtained and morphological aspects and variations of the anatomy related to implant treatment in posterior mandible were presented as two entities: intraosseous mandibular canal and associated inferior alveolar neurovascular bundle. Conclusions A review of morphological aspects and variations of the anatomy related to mandibular canal and mandibular vital structures are very important especially in implant therapy since inferior alveolar neurovascular bundle exists in different locations and possesses many variations. Individual, gender, age, race, assessing technique used and degree of edentulous alveolar bone atrophy largely influence these variations. It suggests that osteotomies in implant dentistry should not be developed in the posterior mandible until the position of the mandibular canal is established. PMID:24421958

Analysis and Visualization of Nerve Vessel Contacts for Neurovascular Decompression

NASA Astrophysics Data System (ADS)

Süßmuth, Jochen; Piazza, Alexander; Enders, Frank; Naraghi, Ramin; Greiner, Günther; Hastreiter, Peter

Neurovascular compression syndromes are caused by a pathological contact between cranial nerves and vascular structures at the surface of the brainstem. Aiming at improved pre-operative analysis of the target structures, we propose calculating distance fields to provide quantitative information of the important nerve-vessel contacts. Furthermore, we suggest reconstructing polygonal models for the nerves and vessels. Color-coding with the respective distance information is used for enhanced visualization. Overall, our new strategy contributes to a significantly improved clinical understanding.

Preoperative evaluation of neurovascular relationships for microvascular decompression in the cerebellopontine angle in a virtual reality environment.

PubMed

Du, Zhuo-Ying; Gao, Xiang; Zhang, Xiao-Luo; Wang, Zhi-Qiu; Tang, Wei-Jun

2010-09-01

In this paper the authors' goal was to evaluate the feasibility and efficacy of a virtual reality (VR) system in preoperative planning for microvascular decompression (MVD) procedures treating idiopathic trigeminal neuralgia and hemifacial spasm. The system's role in surgical simulation and training was also assessed. Between May 2008 and April 2009, the authors used the Dextroscope system to visualize the neurovascular complex and simulate MVD in the cerebellopontine angle in a VR environment in 16 patients (6 patients had trigeminal neuralgia and 10 had hemifacial spasm). Reconstructions were carried out 2-3 days before MVD. Images were printed in a red-blue stereoscopic format for teaching and discussion and were brought into the operating room to be compared with real-time intraoperative findings. The VR environment was a powerful aid for spatial understanding of the neurovascular relationship in MVD for operating surgeons and trainees. Through an initial series of comparison/confirmation experiences, the senior neurosurgeon became accustomed to the system. He could predict intraoperative problems and simulate surgical maneuvering, which increased his confidence in performing the procedure. The Dextroscope system is an easy and rapid method to create a stereoscopic neurovascular model for MVD that is highly concordant with intraoperative findings. It effectively shortens the learning curve and adds to the surgeon's confidence.

Whole-mount Confocal Microscopy for Adult Ear Skin: A Model System to Study Neuro-vascular Branching Morphogenesis and Immune Cell Distribution.

PubMed

Yamazaki, Tomoko; Li, Wenling; Mukouyama, Yoh-Suke

2018-03-29

Here, we present a protocol of a whole-mount adult ear skin imaging technique to study comprehensive three-dimensional neuro-vascular branching morphogenesis and patterning, as well as immune cell distribution at a cellular level. The analysis of peripheral nerve and blood vessel anatomical structures in adult tissues provides some insights into the understanding of functional neuro-vascular wiring and neuro-vascular degeneration in pathological conditions such as wound healing. As a highly informative model system, we have focused our studies on adult ear skin, which is readily accessible for dissection. Our simple and reproducible protocol provides an accurate depiction of the cellular components in the entire skin, such as peripheral nerves (sensory axons, sympathetic axons, and Schwann cells), blood vessels (endothelial cells and vascular smooth muscle cells), and inflammatory cells. We believe this protocol will pave the way to investigate morphological abnormalities in peripheral nerves and blood vessels as well as the inflammation in the adult ear skin under different pathological conditions.

Neurovascular and neuroimaging effects of the hallucinogenic serotonin receptor agonist psilocin in the rat brain

PubMed Central

Spain, Aisling; Howarth, Clare; Khrapitchev, Alexandre A.; Sharp, Trevor; Sibson, Nicola R.; Martin, Chris

2015-01-01

The development of pharmacological magnetic resonance imaging (phMRI) has presented the opportunity for investigation of the neurophysiological effects of drugs in vivo. Psilocin, a hallucinogen metabolised from psilocybin, was recently reported to evoke brain region-specific, phMRI signal changes in humans. The present study investigated the effects of psilocin in a rat model using phMRI and then probed the relationship between neuronal and haemodynamic responses using a multimodal measurement preparation. Psilocin (2 mg/kg or 0.03 mg/kg i.v.) or vehicle was administered to rats (N = 6/group) during either phMRI scanning or concurrent imaging of cortical blood flow and recording of local field potentials. Compared to vehicle controls psilocin (2 mg/kg) evoked phMRI signal increases in a number of regions including olfactory and limbic areas and elements of the visual system. PhMRI signal decreases were seen in other regions including somatosensory and motor cortices. Investigation of neurovascular coupling revealed that whilst neuronal responses (local field potentials) to sensory stimuli were decreased in amplitude by psilocin administration, concurrently measured haemodynamic responses (cerebral blood flow) were enhanced. The present findings show that psilocin evoked region-specific changes in phMRI signals in the rat, confirming recent human data. However, the results also suggest that the haemodynamic signal changes underlying phMRI responses reflect changes in both neuronal activity and neurovascular coupling. This highlights the importance of understanding the neurovascular effects of pharmacological manipulations for interpreting haemodynamic neuroimaging data. PMID:26192543

The Brain’s Heart – Therapeutic Opportunities for Patent Foramen Ovale (PFO) and Neurovascular Disease

PubMed Central

Ning, MingMing; Lo, Eng H.; Ning, Pei-Chen; Xu, Su-Yu; McMullin, David; Demirjian, Zareh; Inglessis, Ignacio; Dec, G William; Palacios, Igor; Buonanno, Ferdinando S.

2013-01-01

Patent foramen ovale (PFO), a common congenital cardiac abnormality, is a connection between the right and left atria in the heart. As a “back door to the brain”, PFO can serve as a conduit for paradoxical embolism, allowing venous thrombi to enter the arterial circulation, avoiding filtration by the lungs, and causing ischemic stroke. PFO-related strokes affect more than 150,000 people per year in the US, and PFO is present in up to 60% of migraine patients with aura, and in one out of four normal individuals. So, in such a highly prevalent condition, what are the best treatment and prevention strategies? Emerging studies show PFO-related neurovascular disease to be a multi-organ condition with varying individual risk factors that may require individualized therapeutic approaches – opening the field for new pharmacologic and therapeutic targets. The anatomy of PFO suggests that, in addition to thrombi, it can also allow harmful circulatory factors to travel directly from the venous to the arterial circulation, a concept important in finding novel therapeutic targets for PFO-related neurovascular injury. Here, we: 1) review emerging data on PFO-related injuries and clinical trials; 2) discuss potential mechanisms of PFO-related neurovascular disease in the context of multi-organ interaction and heart-brain signaling; and 3) discuss novel therapeutic targets and research frontiers. Clinical studies and molecular mapping of the circulatory landscape of this multi-organ disease will both be necessary in order to better individualize clinical treatment for a condition affecting more than a quarter of the world’s population. PMID:23528225

OCT/PS-OCT imaging of brachial plexus neurovascular structures

NASA Astrophysics Data System (ADS)

Raphael, David T.; Zhang, Jun; Zhang, Yaoping; Chen, Zhongping; Miller, Carol; Zhou, Li

2004-07-01

Introduction: Optical coherence tomography (OCT) allows high-resolution imaging (less than 10 microns) of tissue structures. A pilot study with OCT and polarization-sensitive OCT (PS-OCT) was undertaken to image ex-vivo neurovascular structures (vessels, nerves) of the canine brachial plexus. Methods: OCT is an interferometry-based optical analog of B-mode ultrasound, which can image through non-transparent biological tissues. With approval of the USC Animal Care and Use Committee, segments of the supra- and infraclavicular brachial plexus were excised from euthanized adult dogs, and the ex-vivo specimens were placed in cold pH-buffered physiologic solution. An OCT beam, in micrometer translational steps, scanned the fixed-position bisected specimens in transverse and longitudinal views. Two-dimensional images were obtained from identified arteries and nerves, with specific sections of interest stained with hematoxylin-eosin for later imaging through a surgical microscope. Results: with the beam scan direction transverse to arteries, the resulting OCT images showed an identifiable arterial lumen and arterial wall tissue layers. By comparison, transverse beam OCT images of nerves revealed a multitude of smaller nerve bundles contained within larger circular-shaped fascicles. PS-OCT imaging was helpful in showing the characteristic birefringence exhibited by arrayed neural structures. Discussion: High-resolution OCT imaging may be useful in the optical identification of neurovascular structures during attempted regional nerve blockade. If incorporated into a needle-shaped catheter endoscope, such a technology could prevent intraneural and intravascular injections immediately prior to local anesthetic injection. The major limitation of OCT is that it can form a coherent image of tissue structures only to a depth of 1.5 - 2 mm.

Deep brain stimulation does not change neurovascular coupling in non-motor visual cortex: an autonomic and visual evoked blood flow velocity response study.

PubMed

Azevedo, Elsa; Santos, Rosa; Freitas, João; Rosas, Maria-José; Gago, Miguel; Garrett, Carolina; Rosengarten, Bernhard

2010-11-01

In Parkinson's disease (PD) subthalamic nucleus deep brain stimulation (STN-DBS) improves motor function. Also an effect on the neurovascular coupling in motor cortex was reported due to a parallel activation of a subthalamic vasodilator area (SVA). To address this issue further we analysed neurovascular coupling in a non-motor area. Twenty PD patients selected for bilateral STN-DBS were investigated with functional transcranial Doppler (f-TCD) before and after surgery. Hemodynamic responses to visual stimulation were registered in left posterior cerebral artery (PCA) and analysed with a control-system approach (parameters gain, rate time, attenuation and natural frequency). To exclude autonomic effects of STN-DBS, we also addressed spectrum analysis of heart rate and of systolic arterial blood pressure variability, and baroreceptor gain. Findings in the PD group were compared with healthy age-matched controls. PD patients showed no neurovascular coupling changes in PCA territory, compared to controls, and STN-DBS changed neither blood flow regulatory parameters nor autonomic function. Improvement of vasoregulation in some motor cortical areas after STN-DBS might be related to an improved neuronal functional rather than indicating an effect on the neurovascular coupling or autonomic function. Copyright © 2010 Elsevier Ltd. All rights reserved.

Augmented reality in neurovascular surgery: feasibility and first uses in the operating room.

PubMed

Kersten-Oertel, Marta; Gerard, Ian; Drouin, Simon; Mok, Kelvin; Sirhan, Denis; Sinclair, David S; Collins, D Louis

2015-11-01

The aim of this report is to present a prototype augmented reality (AR) intra-operative brain imaging system. We present our experience of using this new neuronavigation system in neurovascular surgery and discuss the feasibility of this technology for aneurysms, arteriovenous malformations (AVMs), and arteriovenous fistulae (AVFs). We developed an augmented reality system that uses an external camera to capture the live view of the patient on the operating room table and to merge this view with pre-operative volume-rendered vessels. We have extensively tested the system in the laboratory and have used the system in four surgical cases: one aneurysm, two AVMs and one AVF case. The developed AR neuronavigation system allows for precise patient-to-image registration and calibration of the camera, resulting in a well-aligned augmented reality view. Initial results suggest that augmented reality is useful for tailoring craniotomies, localizing vessels of interest, and planning resection corridors. Augmented reality is a promising technology for neurovascular surgery. However, for more complex anomalies such as AVMs and AVFs, better visualization techniques that allow one to distinguish between arteries and veins and determine the absolute depth of a vessel of interest are needed.

Sustainable dual-use labs: neurovascular interventional capabilities within the cath lab.

PubMed

Lang, Stacey

2012-01-01

The inclusion of neurovascular interventional capabilities within the cath lab setting can be key to optimal utilization of resources, increased staff efficiency, and streamlined operations. When considering an expansion, look beyond the patient population traditionally associated with cardiac cath labs and consider the integration of programs outside cardiac alone--to create a true dual-use lab space. With proper planning, quality dual purpose equipment, appropriately trained staff, capable physicians, and strong leadership, an organization willing to embrace the challenge can build a truly extraordinary service.

Transection versus preservation of the neurovascular bundle of the lesser omentum in primary Roux-en-Y gastric bypass surgery.

PubMed

van Wezenbeek, Martin R; van Oudheusden, Thijs R; Smulders, J Frans; Nienhuijs, Simon W; Luyer, Misha D

2016-02-01

A gastric pouch in Roux-en-Y gastric bypass (RYGB) surgery can be created after transection of the perigastric neurovascular bundle or by preserving these structures. Some surgeons choose to transect the neurovascular bundle (NBT), containing branches of the vagus nerve, because this might be related to additional weight loss, whereas others advocate preservation (NBP) to reduce postoperative complications. This study assessed the effect of both techniques after primary RYGB. All patients undergoing primary RYGB in a large bariatric center in the Netherlands between January 2010 and December 2013 were included. Patient demographic characteristics, operative details, postoperative complications and weight loss after 1 year were retrospectively analyzed. A total of 773 consecutive patients were included (85.5% female). NBT was performed in 407 patients (52.7%), whereas NBP was performed in 366 patients. There were no missing data and 81.2% of patients completed the 1-year follow-up. Postoperative complications were found in 66 patients (8.5%). A total of 49 patients (6.3%) either had an anastomotic leakage, postoperative bleeding, or intraabdominal abscess (NBT 8.8% versus NBP 3.6%, P = .003). Percentage total weight loss (NBT 34.5%±6.9% versus NBP 33.4%±6.9%; P = .011) differed to a lesser extent between groups, although this was significant. Neurovascular bundle transection was identified as independent factor among others for occurrence of leakage, bleeding, and abscess development (OR 2.886; 95% CI [1.466-5.683]; P = .002). Transection of the neurovascular bundle in RYGB is associated with more complications. Furthermore, weight loss is not relevantly increased. Further research is necessitated to substantiate these findings. Copyright © 2016 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Vasoconstriction and Impairment of Neurovascular Coupling after Subarachnoid Hemorrhage: a Descriptive Analysis of Retinal Changes.

PubMed

Conzen, Catharina; Albanna, Walid; Weiss, Miriam; Kürten, David; Vilser, Walthard; Kotliar, Konstantin; Zäske, Charlotte; Clusmann, Hans; Schubert, Gerrit Alexander

2018-06-01

Impaired cerebral autoregulation and neurovascular coupling (NVC) contribute to delayed cerebral ischemia after subarachnoid hemorrhage (SAH). Retinal vessel analysis (RVA) allows non-invasive assessment of vessel dimension and NVC hereby demonstrating a predictive value in the context of various neurovascular diseases. Using RVA as a translational approach, we aimed to assess the retinal vessels in patients with SAH. RVA was performed prospectively in 24 patients with acute SAH (group A: day 5-14), in 11 patients 3 months after ictus (group B: day 90 ± 35), and in 35 age-matched healthy controls (group C). Data was acquired using a Retinal Vessel Analyzer (Imedos Systems UG, Jena) for examination of retinal vessel dimension and NVC using flicker-light excitation. Diameter of retinal vessels-central retinal arteriolar and venular equivalent-was significantly reduced in the acute phase (p < 0.001) with gradual improvement in group B (p < 0.05). Arterial NVC of group A was significantly impaired with diminished dilatation (p < 0.001) and reduced area under the curve (p < 0.01) when compared to group C. Group B showed persistent prolonged latency of arterial dilation (p < 0.05). Venous NVC was significantly delayed after SAH compared to group C (A p < 0.001; B p < 0.05). To our knowledge, this is the first clinical study to document retinal vasoconstriction and impairment of NVC in patients with SAH. Using non-invasive RVA as a translational approach, characteristic patterns of compromise were detected for the arterial and venous compartment of the neurovascular unit in a time-dependent fashion. Recruitment will continue to facilitate a correlation analysis with clinical course and outcome.

Neurovascular coupling in normal aging: a combined optical, ERP and fMRI study.

PubMed

Fabiani, Monica; Gordon, Brian A; Maclin, Edward L; Pearson, Melanie A; Brumback-Peltz, Carrie R; Low, Kathy A; McAuley, Edward; Sutton, Bradley P; Kramer, Arthur F; Gratton, Gabriele

2014-01-15

Brain aging is characterized by changes in both hemodynamic and neuronal responses, which may be influenced by the cardiorespiratory fitness of the individual. To investigate the relationship between neuronal and hemodynamic changes, we studied the brain activity elicited by visual stimulation (checkerboard reversals at different frequencies) in younger adults and in older adults varying in physical fitness. Four functional brain measures were used to compare neuronal and hemodynamic responses obtained from BA17: two reflecting neuronal activity (the event-related optical signal, EROS, and the C1 response of the ERP), and two reflecting functional hemodynamic changes (functional magnetic resonance imaging, fMRI, and near-infrared spectroscopy, NIRS). The results indicated that both younger and older adults exhibited a quadratic relationship between neuronal and hemodynamic effects, with reduced increases of the hemodynamic response at high levels of neuronal activity. Although older adults showed reduced activation, similar neurovascular coupling functions were observed in the two age groups when fMRI and deoxy-hemoglobin measures were used. However, the coupling between oxy- and deoxy-hemoglobin changes decreased with age and increased with increasing fitness. These data indicate that departures from linearity in neurovascular coupling may be present when using hemodynamic measures to study neuronal function. Copyright © 2013 Elsevier Inc. All rights reserved.

Structural and physiological neurovascular changes in idiopathic Parkinson's disease and its clinical phenotypes.

PubMed

Al-Bachari, Sarah; Vidyasagar, Rishma; Emsley, Hedley Ca; Parkes, Laura M

2017-10-01

Neurovascular changes are likely to interact importantly with the neurodegenerative process in idiopathic Parkinson's disease (IPD). Markers of neurovascular status (NVS) include white matter lesion (WML) burden and arterial spin labelling (ASL) measurements of cerebral blood flow (CBF) and arterial arrival time (AAT). We investigated NVS in IPD, including an analysis of IPD clinical phenotypes, by comparison with two control groups, one with a history of clinical cerebrovascular disease (CVD) (control positive, CP) and one without CVD (control negative, CN). Fifty-one patients with IPD (mean age 69.0 ± 7.7 years) (21 tremor dominant (TD), 24 postural instability and gait disorder (PIGD) and six intermediates), 18 CP (mean age 70.1 ± 8.0 years) and 34 CN subjects (mean age 67.4 ± 7.6 years) completed a 3T MRI scan protocol including T 2 -weighted fluid-attenuated inversion recovery (FLAIR) and ASL. IPD patients showed diffuse regions of significantly prolonged AAT, small regions of lower CBF and greater WML burden by comparison with CN subjects. TD patients showed lower WML volume by comparison with PIGD patients. These imaging data thus show altered NVS in IPD, with some evidence for IPD phenotype-specific differences.

Curcumin-loaded embryonic stem cell exosomes restored neurovascular unit following ischemia-reperfusion injury.

PubMed

Kalani, Anuradha; Chaturvedi, Pankaj; Kamat, Pradip K; Maldonado, Claudio; Bauer, Philip; Joshua, Irving G; Tyagi, Suresh C; Tyagi, Neetu

2016-10-01

We tested whether the combined nano-formulation, prepared with curcumin (anti-inflammatory and neuroprotective molecule) and embryonic stem cell exosomes (MESC-exo cur ), restored neurovascular loss following an ischemia reperfusion (IR) injury in mice. IR-injury was created in 8-10 weeks old mice and divided into two groups. Out of two IR-injured groups, one group received intranasal administration of MESC-exo cur for 7days. Similarly, two sham groups were made and one group received MESC-exo cur treatment. The study determined that MESC-exo cur treatment reduced neurological score, infarct volume and edema following IR-injury. As compared to untreated IR group, MESC-exo cur treated-IR group showed reduced inflammation and N-methyl-d-aspartate receptor expression. Treatment of MESC-exo cur also reduced astrocytic GFAP expression and alleviated the expression of NeuN positive neurons in IR-injured mice. In addition, MESC-exo cur treatment restored vascular endothelial tight (claudin-5 and occludin) and adherent (VE-cadherin) junction proteins in IR-injured mice as compared to untreated IR-injured mice. These results suggest that combining the potentials of embryonic stem cell exosomes and curcumin can help neurovascular restoration following ischemia-reperfusion injury in mice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Confrontando teorías físicas con la Cosmología

NASA Astrophysics Data System (ADS)

Vucetich, H.

Hay numerosas teorías físicas que no pueden contrastarse con el experimento en laboratorio y eso las hace poco interesantes como descripción de la naturaleza. Sin embargo, algunas de estas teorías tienen consecuencias cosmológicas observables y se abre la posibilidad de contrastación a través de la observación. Se discuten las observaciones capaces de poner a prueba tales teorías y se examinan ejemplos de teorías limitadas por la observación.

Computational modeling of the neurovascular unit to predict microglia mediated effects on blood-brain barrier formation (WC10)

EPA Science Inventory

Development of the neurovascular unit (NVU) involves interactions between endothelial cells, pericytes, neuroprogenitor cells, and microglia. We constructed an in silico model of the developing neuroepithelium in CompuCell3D which recapitulated a suite of critical signaling pathw...

Neurovascular structures of the mandibular angle and condyle: a comprehensive anatomical review.

PubMed

Yang, Hun-Mu; Won, Sung-Yoon; Kim, Hee-Jin; Hu, Kyung-Seok

2015-11-01

Various surgical interventions including esthetic surgery, salivary gland excision, and open reduction of fracture have been performed in the area around the mandibular angle and condyle. This study aimed to comprehensively review the anatomy of the neurovascular structures on the angle and condyle with recent anatomic and clinical research. We provide detailed information about the branching and distributing patterns of the neurovascular structures at the mandibular angle and condyle, with reported data of measurements and proportions from previous anatomical and clinical research. Our report should serve to help practitioners gain a better understanding of the area in order or reduce potential complications during local procedures. Reckless manipulation during mandibular angle reduction could mutilate arterial branches, not only from the facial artery, but also from the external carotid artery. The transverse facial artery and superficial temporal artery could be damaged during approach and incision in the condylar area. The marginal mandibular branch of the facial nerve can be easily damaged during submandibular gland excision or facial rejuvenation treatment. The main trunk of the facial nerve and its upper and lower distinct divisions have been damaged during parotidectomy, rhytidectomy, and open reductions of condylar fractures. By revisiting the information in the present study, surgeons will be able to more accurately prevent procedure-related complications, such as iatrogenic vascular accidents on the mandibular angle and condyle, complete and partial facial palsy, gustatory sweating (Frey syndrome), and traumatic neuroma after parotidectomy.

Skeletal Muscle Neurovascular Coupling, Oxidative Capacity, and Microvascular Function with 'One Stop Shop' Near-infrared Spectroscopy.

PubMed

Rosenberry, Ryan; Chung, Susie; Nelson, Michael D

2018-02-20

Exercise represents a major hemodynamic stress that demands a highly coordinated neurovascular response in order to match oxygen delivery to metabolic demand. Reactive hyperemia (in response to a brief period of tissue ischemia) is an independent predictor of cardiovascular events and provides important insight into vascular health and vasodilatory capacity. Skeletal muscle oxidative capacity is equally important in health and disease, as it determines the energy supply for myocellular processes. Here, we describe a simple, non-invasive approach using near-infrared spectroscopy to assess each of these major clinical endpoints (reactive hyperemia, neurovascular coupling, and muscle oxidative capacity) during a single clinic or laboratory visit. Unlike Doppler ultrasound, magnetic resonance images/spectroscopy, or invasive catheter-based flow measurements or muscle biopsies, our approach is less operator-dependent, low-cost, and completely non-invasive. Representative data from our lab taken together with summary data from previously published literature illustrate the utility of each of these end-points. Once this technique is mastered, application to clinical populations will provide important mechanistic insight into exercise intolerance and cardiovascular dysfunction.

Anatomy of Mandibular Vital Structures. Part II: Mandibular Incisive Canal, Mental Foramen and Associated Neurovascular Bundles in Relation with Dental Implantology

PubMed Central

Wang, Hom-Lay; Sabalys, Gintautas

2010-01-01

ABSTRACT Objectives The purpose of the present study was to review the literature of how to identify the mental foramen, mandibular incisive canal and associated neurovascular bundles during implant surgery and how to detect and avoid the damage of these vital structures during implant therapy. Material and Methods Literature was selected through a search of PubMed, Embase and Cochrane electronic databases. The keywords used for search were mandibular incisive canal, mental foramen, mental nerve, anterior mental loop. The search was restricted to English language articles, published from 1979 to November 2009. Additionally, a manual search in the major anatomy, dental implant, and periodontal journals and books was performed. Results In total, 47 literature sources were obtained and reviewed. The morphology and variations of the mandibular incisive canal, mental foramen and associated neurovascular bundles were presented as two entities. It suggested that clinicians should carefully assess these vital structures to avoid nerve/artery damage. Conclusions The mandibular incisive canal, mental foramen and associated neurovascular bundles exist in different locations and possess many variations. Individual, gender, age, race, assessing technique used and degree of edentulous alveolar bone atrophy largely influence these variations. It suggests that the clinicians should carefully identify these anatomical landmarks, by analyzing all influencing factors, prior to their implant surgical operation. PMID:24421959

Robot-assisted laparoscopic radical prostatectomy with early retrograde release of the neurovascular bundle and endopelvic fascia sparing

PubMed Central

de Albuquerque, George Augusto Monteiro Lins; Guglielmetti, Giuliano Betoni; Cordeiro, Maurício Dener; Nahas, William Carlos; Coelho, Rafael Ferreira

2017-01-01

ABSTRACT Introduction Robotic-assisted radical prostatectomy (RAP) is the dominant minimally invasive surgical treatment for patients with localized prostate cancer. The introduction of robotic assistance has the potential to improve surgical outcomes and reduce the steep learning curve associated with conventional laparoscopic radical prostatectomy. The purpose of this video is to demonstrate the early retrograde release of the neurovascular bundle without open the endopelvic fascia during RAP. Materials and Methods A 51-year old male, presenting histological diagnosis of prostate adenocarcinoma, Gleason 6 (3+3), in 4 cores of 12, with an initial PSA=3.41ng/dl and the digital rectal examination demonstrating a prostate with hardened nodule in the right lobe of the prostate base (clinical stage T2a). Surgical treatment with the robot-assisted technique was offered as initial therapeutic option and the critical technical point was the early retrograde release of the neurovascular bundle with endopelvic fascia preservation, during radical prostatectomy. Results The operative time was of 89 minutes, blood loss was 100ml. No drain was left in the peritoneal cavity. The patient was discharged within 24 hours. There were no intraoperative or immediate postoperative complications. The pathological evaluation revealed prostate adenocarcinoma, Gleason 6, with free surgical margins and seminal vesicles free of neoplastic involvement (pathologic stage T2a). At 3-month-follow-up, the patient lies with undetectable PSA, continent and potent. Conclusion This is a feasible technique combining the benefits of retrograde release of the neurovascular bundle, the preservation of the pubo-prostatic collar and the preservation of the antero-lateral cavernous nerves. PMID:27802002

Neurovascular Study of the Trigeminal Nerve at 3 T MRI

PubMed Central

Gonzalez, Nadia; Muñoz, Alexandra; Bravo, Fernando; Sarroca, Daniel; Morales, Carlos

2015-01-01

This study aimed to show a novel visualization method to investigate neurovascular compression of the trigeminal nerve (TN) using a volume-rendering fusion imaging technique of 3D fast imaging employing steady-state acquisition (3D FIESTA) and coregistered 3D time of flight MR angiography (3D TOF MRA) sequences, which we called “neurovascular study of the trigeminal nerve”. We prospectively studied 30 patients with unilateral trigeminal neuralgia (TN) and 50 subjects without symptoms of TN (control group), on a 3 Tesla scanner. All patients were assessed using 3D FIESTA and 3D TOF MRA sequences centered on the pons, as well as a standard brain protocol including axial T1, T2, FLAIR and GRE sequences to exclude other pathologies that could cause TN. Post-contrast T1-weighted sequences were also performed. All cases showing arterial imprinting on the trigeminal nerve (n = 11) were identified on the ipsilateral side of the pain. No significant relationship was found between the presence of an artery in contact with the trigeminal nerve and TN. Eight cases were found showing arterial contact on the ipsilateral side of the pain and five cases of arterial contact on the contralateral side. The fusion imaging technique of 3D FIESTA and 3D TOF MRA sequences, combining the high anatomical detail provided by the 3D FIESTA sequence with the 3D TOF MRA sequence and its capacity to depict arterial structures, results in a tool that enables quick and efficient visualization and assessment of the relationship between the trigeminal nerve and the neighboring vascular structures. PMID:25924169

Neurovascular unit dysfunction with blood-brain barrier hyperpermeability contributes to major depressive disorder: a review of clinical and experimental evidence

PubMed Central

2013-01-01

About one-third of people with major depressive disorder (MDD) fail at least two antidepressant drug trials at 1 year. Together with clinical and experimental evidence indicating that the pathophysiology of MDD is multifactorial, this observation underscores the importance of elucidating mechanisms beyond monoaminergic dysregulation that can contribute to the genesis and persistence of MDD. Oxidative stress and neuroinflammation are mechanistically linked to the presence of neurovascular dysfunction with blood-brain barrier (BBB) hyperpermeability in selected neurological disorders, such as stroke, epilepsy, multiple sclerosis, traumatic brain injury, and Alzheimer’s disease. In contrast to other major psychiatric disorders, MDD is frequently comorbid with such neurological disorders and constitutes an independent risk factor for morbidity and mortality in disorders characterized by vascular endothelial dysfunction (cardiovascular disease and diabetes mellitus). Oxidative stress and neuroinflammation are implicated in the neurobiology of MDD. More recent evidence links neurovascular dysfunction with BBB hyperpermeability to MDD without neurological comorbidity. We review this emerging literature and present a theoretical integration between these abnormalities to those involving oxidative stress and neuroinflammation in MDD. We discuss our hypothesis that alterations in endothelial nitric oxide levels and endothelial nitric oxide synthase uncoupling are central mechanistic links in this regard. Understanding the contribution of neurovascular dysfunction with BBB hyperpermeability to the pathophysiology of MDD may help to identify novel therapeutic and preventative approaches. PMID:24289502

The oxygen paradox of neurovascular coupling

PubMed Central

Leithner, Christoph; Royl, Georg

2014-01-01

The coupling of cerebral blood flow (CBF) to neuronal activity is well preserved during evolution. Upon changes in the neuronal activity, an incompletely understood coupling mechanism regulates diameter changes of supplying blood vessels, which adjust CBF within seconds. The physiologic brain tissue oxygen content would sustain unimpeded brain function for only 1 second if continuous oxygen supply would suddenly stop. This suggests that the CBF response has evolved to balance oxygen supply and demand. Surprisingly, CBF increases surpass the accompanying increases of cerebral metabolic rate of oxygen (CMRO2). However, a disproportionate CBF increase may be required to increase the concentration gradient from capillary to tissue that drives oxygen delivery. However, the brain tissue oxygen content is not zero, and tissue pO2 decreases could serve to increase oxygen delivery without a CBF increase. Experimental evidence suggests that CMRO2 can increase with constant CBF within limits and decreases of baseline CBF were observed with constant CMRO2. This conflicting evidence may be viewed as an oxygen paradox of neurovascular coupling. As a possible solution for this paradox, we hypothesize that the CBF response has evolved to safeguard brain function in situations of moderate pathophysiological interference with oxygen supply. PMID:24149931

A neurovascular perspective for long-term changes after brain trauma.

PubMed

Pop, V; Badaut, J

2011-12-01

Traumatic brain injury (TBI) affects all age groups in a population and is an injury generating scientific interest not only as an acute event, but also as a complex brain disease with several underlying neurobehavioral and neuropathological characteristics. We review early and long-term alterations after juvenile and adult TBI with a focus on changes in the neurovascular unit (NVU), including neuronal interactions with glia and blood vessels at the blood-brain barrier (BBB). Post-traumatic changes in cerebral blood-flow, BBB structures and function, as well as mechanistic pathways associated with brain aging and neurodegeneration are presented from clinical and experimental reports. Based on the literature, increased attention on BBB changes should be integrated in studies characterizing TBI outcome and may provide a meaningful therapeutic target to resolve detrimental post-traumatic dysfunction.

[Neurovascular compression of the medulla oblongata: a rare cause of secondary hypertension].

PubMed

Nádas, Judit; Czirják, Sándor; Igaz, Péter; Vörös, Erika; Jermendy, György; Rácz, Károly; Tóth, Miklós

2014-05-25

Compression of the rostral ventrolateral medulla oblongata is one of the rarely identified causes of refractory hypertension. In patients with severe, intractable hypertension caused by neurovascular compression, neurosurgical decompression should be considered. The authors present the history of a 20-year-old man with severe hypertension. After excluding other possible causes of secondary hypertension, the underlying cause of his high blood pressure was identified by the demonstration of neurovascular compression shown by magnetic resonance angiography and an increased sympathetic activity (sinus tachycardia) during the high blood pressure episodes. Due to frequent episodes of hypertensive crises, surgical decompression was recommended, which was performed with the placement of an isograft between the brainstem and the left vertebral artery. In the first six months after the operation, the patient's blood pressure could be kept in the normal range with significantly reduced doses of antihypertensive medication. Repeat magnetic resonance angiography confirmed the cessation of brainstem compression. After six months, increased blood pressure returned periodically, but to a smaller extent and less frequently. Based on the result of magnetic resonance angiography performed 22 months after surgery, re-operation was considered. According to previous literature data long-term success can only be achieved in one third of patients after surgical decompression. In the majority of patients surgery results in a significant decrease of blood pressure, an increased efficiency of antihypertensive therapy as well as a decrease in the frequency of highly increased blood pressure episodes. Thus, a significant improvement of the patient's quality of life can be achieved. The case of this patient is an example of the latter scenario.

3-D Imaging Reveals Participation of Donor Islet Schwann Cells and Pericytes in Islet Transplantation and Graft Neurovascular Regeneration.

PubMed

Juang, Jyuhn-Huarng; Kuo, Chien-Hung; Peng, Shih-Jung; Tang, Shiue-Cheng

2015-02-01

The primary cells that participate in islet transplantation are the endocrine cells. However, in the islet microenvironment, the endocrine cells are closely associated with the neurovascular tissues consisting of the Schwann cells and pericytes, which form sheaths/barriers at the islet exterior and interior borders. The two cell types have shown their plasticity in islet injury, but their roles in transplantation remain unclear. In this research, we applied 3-dimensional neurovascular histology with cell tracing to reveal the participation of Schwann cells and pericytes in mouse islet transplantation. Longitudinal studies of the grafts under the kidney capsule identify that the donor Schwann cells and pericytes re-associate with the engrafted islets at the peri-graft and perivascular domains, respectively, indicating their adaptability in transplantation. Based on the morphological proximity and cellular reactivity, we propose that the new islet microenvironment should include the peri-graft Schwann cell sheath and perivascular pericytes as an integral part of the new tissue.

Systematic review on randomized controlled clinical trials of acupuncture therapy for neurovascular headache.

PubMed

Zhao, Lei; Guo, Yi; Wang, Wei; Yan, Li-juan

2011-08-01

To evaluate the effectiveness of acupuncture as a treatment for neurovascular headache and to analyze the current situation related to acupuncture treatment. PubMed database (1966-2010), EMBASE database (1986-2010), Cochrane Library (Issue 1, 2010), Chinese Biomedical Literature Database (1979-2010), China HowNet Knowledge Database (1979-2010), VIP Journals Database (1989-2010), and Wanfang database (1998-2010) were retrieved. Randomized or quasi-randomized controlled studies were included. The priority was given to high-quality randomized, controlled trials. Statistical outcome indicators were measured using RevMan 5.0.20 software. A total of 16 articles and 1 535 cases were included. Meta-analysis showed a significant difference between the acupuncture therapy and Western medicine therapy [combined RR (random efficacy model)=1.46, 95% CI (1.21, 1.75), Z=3.96, P<0.0001], indicating an obvious superior effect of the acupuncture therapy; significant difference also existed between the comprehensive acupuncture therapy and acupuncture therapy alone [combined RR (fixed efficacy model)=3.35, 95% CI (1.92, 5.82), Z=4.28, P<0.0001], indicating that acupuncture combined with other therapies, such as points injection, scalp acupuncture, auricular acupuncture, etc., were superior to the conventional body acupuncture therapy alone. The inclusion of limited clinical studies had verified the efficacy of acupuncture in the treatment of neurovascular headache. Although acupuncture or its combined therapies provides certain advantages, most clinical studies are of small sample sizes. Large sample size, randomized, controlled trials are needed in the future for more definitive results.

Autonomic dysfunction affects cerebral neurovascular coupling.

PubMed

Azevedo, Elsa; Castro, Pedro; Santos, Rosa; Freitas, João; Coelho, Teresa; Rosengarten, Bernhard; Panerai, Ronney

2011-12-01

Autonomic failure (AF) affects the peripheral vascular system, but little is known about its influence on cerebrovascular regulation. Patients with familial amyloidotic polyneuropathy (FAP) were studied as a model for AF. Ten mild (FAPm), 10 severe (FAPs) autonomic dysfunction FAP patients, and 15 healthy controls were monitored in supine and sitting positions for arterial blood pressure (ABP) and heart rate (HR) with arterial volume clamping, and for blood flow velocity (BFV) in posterior (PCA) and contralateral middle cerebral arteries (MCA) with transcranial Doppler. Analysis included resting BFV, cerebrovascular resistance parameters (cerebrovascular resistance index, CVRi; resistance area product, RAP; and critical closing pressure, CrCP), and neurovascular coupling through visually evoked BFV responses in PCA (gain, rate time, attenuation, and natural frequency). In non-stimulation conditions, in each position, there were no significant differences between the groups, regarding HR, BP, resting BFV, and vascular resistance parameters. Sitting ABP was higher than in supine in the three groups, although only significantly in controls. Mean BFV was lower in sitting in all the groups, lacking statistical significance only in FAPs PCA. CVRi and CrCP increased with sitting in all the groups, while RAP increased in controls but decreased in FAPm and FAPs. In visual stimulation conditions, FAPs comparing to controls had a significant decrease of natural frequency, in supine and sitting, and of rate time and gain in sitting position. These results demonstrate that cerebrovascular regulation is affected in FAP subjects with AF, and that it worsens with orthostasis.

Dynamic Neurovascular Coupling and Uncoupling during Ictal Onset, Propagation, and Termination Revealed by Simultaneous In Vivo Optical Imaging of Neural Activity and Local Blood Volume

PubMed Central

Zhao, Mingrui; Schwartz, Theodore H.

2013-01-01

Traditional models of ictal propagation involve the concept of an initiation site and a progressive outward march of activation. The process of neurovascular coupling, whereby the brain supplies oxygenated blood to metabolically active neurons presumably results in a similar outward cascade of hyperemia. However, ictal neurovascular coupling has never been assessed in vivo using simultaneous measurements of membrane potential change and hyperemia with wide spatial sampling. In an acute rat ictal model, using simultaneous intrinsic optical signal (IOS) and voltage-sensitive dye (VSD) imaging of cerebral blood volume and membrane potential changes, we demonstrate that seizures consist of multiple dynamic multidirectional waves of membrane potential change with variable onset sites that spread through a widespread network. Local blood volume evolves on a much slower spatiotemporal scale. At seizure onset, the VSD waves extend beyond the IOS signal. During evolution, spatial correlation with hemodynamic signal only exists briefly at the maximal spread of the VSD signal. At termination, the IOS signal extends spatially and temporally beyond the VSD waves. Hence, vascular reactivity evolves in a separate but parallel fashion to membrane potential changes resulting in a mechanism of neurovascular coupling and uncoupling, which is as dynamic as the seizure itself. PMID:22499798

Ultrastructure of neurovascular changes in human diabetic retinopathy.

PubMed

Fehér, János; Taurone, Samanta; Spoletini, Marialuisa; Biró, Zsolt; Varsányi, Balázs; Scuderi, Gianluca; Orlando, Maria Patrizia; Turchetta, Rosaria; Micera, Alessandra; Artico, Marco

2018-01-01

The previous concept regarding diabetic retinopathy assigned a primary role to hyperglycemia-induced microvascular alterations, while neuronal and glial abnormalities were considered to be secondary to either ischemia or exudation. The aim of this study was to reveal the potential role of neuronal and glial cells in initial and advanced alterations of the retinopathy in human type 2 diabetes. Electron microscopy and histochemical studies were performed on 38 surgically removed human eyes (28 obtained from diabetic patients and 10 from non-diabetic patients). Morphometric analysis of basement membrane material and lipids was performed. An accumulation of metabolic by-products was found in the capillary wall with aging: this aspect was significantly more pronounced in diabetics. Müller glial cells were found to contribute to alterations of the capillary wall and to occlusion, as well as to the development of proliferative retinopathy and cystoid degeneration of the retina. Our results showed morphological evidence regarding the role of neuronal and glial cells in the pathology of diabetic retinopathy, prior and in addition to microangiopathy. These morphological findings support a neurovascular pathogenesis at the origin of diabetic retinopathy, thus the current treatment approach should be completed by neuroprotective measures.

Severity-dependent influence of isocapnic hypoxia on reaction time is independent of neurovascular coupling.

PubMed

Caldwell, Hannah G; Coombs, Geoff B; Tymko, Michael M; Nowak-Flück, Daniela; Ainslie, Philip N

2018-05-01

With exposure to acute normobaric hypoxia, global cerebral oxygen delivery is maintained via increases in cerebral blood flow (CBF); therefore, regional and localized changes in oxygen tension may explain neurocognitive impairment. Neurovascular coupling (NVC) is the close temporal and regional relationship of CBF to changes in neural activity and may aid in explaining the localized CBF response with cognitive activation. High-altitude related cognitive impairment is likely affected by hypocapnic cerebral vasoconstriction that may influence regional CBF regulation independent of hypoxia. We assessed neurocognition and NVC following 30 min of acute exposure to isocapnic hypoxia (decreased partial pressure of end-tidal oxygen; P ET O 2 ) during moderate hypoxia (MOD HX; 55 mm Hg P ET O 2 ), and severe hypoxia (SEV HX; 45 mm Hg P ET O 2 ) in 10 healthy individuals (25.5 ± 3.3 yrs). Transcranial Doppler ultrasound was used to assess mean posterior and middle cerebral blood velocity (PCAv and MCAv, respectively) and neurocognitive performance was assessed via validated computerized tests. The main finding was that reaction time (i.e., kinesthetic and visual-motor ability via Stroop test) was selectively impaired in SEV HX (-4.6 ± 5.2%, P = 0.04), but not MOD HX, while complex cognitive performance (e.g., psychomotor speed, cognitive flexibility, processing speed, executive function, and motor speed) was unaffected with hypoxia (P > 0.05). Additionally, severity of hypoxia had no effect on NVC (PCAv CON vs. SEV HX relative peak response 13.7 ± 6.4% vs. 16.2 ± 11.5%, P = 0.71, respectively). In summary, severe isocapnic hypoxia impaired reaction time, but not complex cognitive performance or NVC. These findings have implications for recreational and military personnel who may experience acute hypoxia. Copyright © 2018 Elsevier Inc. All rights reserved.

Targeting the neurovascular unit for treatment of neurological disorders.

PubMed

Vangilder, Reyna L; Rosen, Charles L; Barr, Taura L; Huber, Jason D

2011-06-01

Drug discovery for CNS disorders has been restricted by the inability for therapeutic agents to cross the blood-brain barrier (BBB). Moreover, current drugs aim to correct neuron cell signaling, thereby neglecting pathophysiological changes affecting other cell types of the neurovascular unit (NVU). Components of the NVU (pericytes, microglia, astrocytes, and neurons, and basal lamina) act as an intricate network to maintain the neuronal homeostatic microenvironment. Consequently, disruptions to this intricate cell network lead to neuron malfunction and symptoms characteristic of CNS diseases. A lack of understanding in NVU signaling cascades may explain why current treatments for CNS diseases are not curative. Current therapies treat symptoms by maintaining neuron function. Refocusing drug discovery to sustain NVU function may provide a better method of treatment by promoting neuron survival. In this review, we will examine current therapeutics for common CNS diseases, describe the importance of the NVU in cerebral homeostasis and discuss new possible drug targets and technologies that aim to improve treatment and drug delivery to the diseased brain. Copyright © 2011 Elsevier Inc. All rights reserved.

Visual cycle modulation in neurovascular retinopathy.

PubMed

Akula, James D; Hansen, Ronald M; Tzekov, Radouil; Favazza, Tara L; Vyhovsky, Tanya C; Benador, Ilan Y; Mocko, Julie A; McGee, David; Kubota, Ryo; Fulton, Anne B

2010-08-01

Rats with oxygen-induced retinopathy (OIR) model the pediatric retinal disease retinopathy of prematurity (ROP). Recent findings in OIR rats imply a causal role for the rods in the ROP disease process, although only experimental manipulation of rod function can establish this role conclusively. Accordingly, a visual cycle modulator (VCM) - with no known direct effect on retinal vasculature - was administered to "50/10 model" OIR Sprague-Dawley rats to test the hypotheses that it would 1) alter rod function and 2) consequently alter vascular outcome. Four litters of pups (N=46) were studied. For two weeks, beginning on postnatal day (P) 7, the first and fourth litters were administered 6 mg kg(-1) N-retinylacetamide (the VCM) intraperitoneally; the second and third litters received vehicle (DMSO) alone. Following a longitudinal design, retinal function was assessed by electroretinography (ERG) and the status of the retinal vessels was monitored using computerized fundus photograph analysis. Rod photoreceptor and post-receptor response amplitudes were significantly higher in VCM-treated than in vehicle-treated rats; deactivation of phototransduction was also significantly more rapid. Notably, the arterioles of VCM-treated rats showed significantly greater recovery from OIR. Presuming that the VCM did not directly affect the retinal vessels, a causal role for the neural retina - particularly the rod photoreceptors - in OIR was confirmed. There was no evidence of negative alteration of photoreceptor function consequent to VCM treatment. This finding implicates the rods as a possible therapeutic target in neurovascular diseases such as ROP. Copyright 2010 Elsevier Ltd. All rights reserved.

Neurovascular risks of sacral screws with bicortical purchase: an anatomical study.

PubMed

Ergur, Ipek; Akcali, Omer; Kiray, Amac; Kosay, Can; Tayefi, Hamid

2007-09-01

The aim of this cadaver study is to define the anatomic structures on anterior sacrum, which are under the risk of injury during bicortical screw application to the S1 and S2 pedicles. Thirty formaldehyde-preserved human male cadavers were studied. Posterior midline incision was performed, and soft tissues and muscles were dissected from the posterior part of the lumbosacral region. A 6 mm pedicle screw was inserted between the superior facet of S1 and the S1 foramen. The entry point of the S2 pedicle screw was located between S1 and S2 foramina. S1 and S2 screws were placed on both right and the left sides of all cadavers. Then, all cadavers were turned into supine position. All abdominal and pelvic organs were moved away and carefully observed for any injury. The tips of the sacral screws were marked and the relations with the anatomic structures were defined. The position of the sacral screws relative to the middle and lateral sacral arteries and veins, and the sacral sympathetic trunk were measured. There was no injury to the visceral organs. In four cases, S1 screw tip was in direct contact with middle sacral artery. In two cases, S1 screw tip was in direct contact with middle sacral vein. It was observed that the S1 screw tips were in close proximity to sacral sympathetic trunk on both right and the left sides. The tip of the S2 screw was in contact with middle sacral artery on the left side only in one case. It is found that the tip of the S2 screw was closely located with the middle sacral vein in two cases. The tip of the S2 pedicle screw was in contact with the sacral sympathetic trunk in eight cases on the right side and seven cases on the left side. Lateral sacral vein was also observed to be disturbed by the S1 and S2 screws. As a conclusion, anterior cortical penetration during sacral screw insertion carries a risk of neurovascular injury. The risk of sacral sympathetic trunk and minor vascular structures together with the major neurovascular

Prostate tissue ablation with MRI guided transurethral therapeutic ultrasound and intraoperative assessment of the integrity of the neurovascular bundle

NASA Astrophysics Data System (ADS)

Sammet, Steffen; Partanen, Ari; Yousuf, Ambereen; Wardrip, Craig; Niekrasz, Marek; Antic, Tatjana; Razmaria, Aria; Sokka, Sham; Karczmar, Gregory; Oto, Aytekin

2017-03-01

OBJECTIVES: Evaluation of the precision of prostate tissue ablation with MRI guided therapeuticultrasound by intraoperative objective assessment of the neurovascular bundle in canines in-vivo. METHODS: In this ongoing IACUC approved study, eight male canines were scanned in a clinical 3T Achieva MRI scanner (Philips) before, during, and after ultrasound therapy with a prototype MR-guided ultrasound therapy system (Philips). The system includes a therapy console to plan treatment, to calculate real-time temperature maps, and to control ultrasound exposures with temperature feedback. Atransurethral ultrasound applicator with eight transducer elements was used to ablate canine prostate tissue in-vivo. Ablated prostate tissue volumes were compared to the prescribed target volumes to evaluate technical effectiveness. The ablated volumes determined by MRI (T1, T2, diffusion, dynamic contrast enhanced and 240 CEM43 thermal dose maps) were compared to H&E stained histological slides afterprostatectomy. Potential nerve damage of the neurovascular bundle was objectively assessed intraoperativelyduring prostatectomy with a CaverMap Surgical Aid nerve stimulator (Blue Torch Medical Technologies). RESULTS: Transurethral MRI -guided ultrasound therapy can effectively ablate canine prostate tissue invivo. Coronal MR-imaging confirmed the correct placement of the HIFU transducer. MRI temperature maps were acquired during HIFU treatment, and subsequently used for calculating thermal dose. Prescribed target volumes corresponded to the 240 CEM43 thermal dose maps during HIFU treatment in all canines. Ablated volumes on high resolution anatomical, diffusion weighted, and contrast enhanced MR images matched corresponding histological slides after prostatectomy. MRI guidance with realtime temperature monitoring showed no damage to surrounding tissues, especially to the neurovascular bundle (assessed intra-operatively with a nerve stimulator) or to the rectum wall. CONCLUSIONS: Our study

Free Neurovascular Latissimus Dorsi Muscle Transplantation for Reconstruction of Hip Abductors.

PubMed

Barrera-Ochoa, Sergi; Collado-Delfa, Jose Manuel; Sallent, Andrea; Lluch, Alejandro; Velez, Roberto

2017-09-01

Resection of tumors affecting the hip abductors can cause significant decrease in muscle strength and may lead to abnormal gait and poor function. We present a case report showing full functional recovery after resection of a synovial sarcoma affecting the right gluteus medius and minimus muscles with reconstruction free neurovascular latissimus dorsi muscle transplantation. The latissimus dorsi muscle was harvested following standard technique and fixed to the ilium and the greater trochanter. Receptor vessels were end-to-end anastomosed to the subscapular vessels followed by an end-to-end epineural suture between the superior gluteal nerve and the thoracodorsal nerve. A year after surgery, there is no evidence of recurrent disease; electromyographic analysis shows complete reinnervation of the latissimus dorsi muscle flap, and the patient has achieved full functional recovery. Free functional latisimus dorsi transfer could be considered as a viable reconstruction technique after hip abductors resection in tumor surgery.

Prefrontal white matter pathology in air pollution exposed Mexico City young urbanites and their potential impact on neurovascular unit dysfunction and the development of Alzheimer's disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calderón-Garcidueñas, Lilian, E-mail: lilian.calderon-garciduenas@umontana.edu; Universidad del Valle de México, Mexico City 04850, México; Reynoso-Robles, Rafael

Millions of urban children are chronically exposed to high concentrations of air pollutants, i.e., fine particulate matter (PM{sub 2.5}) and ozone, associated with increased risk for Alzheimer's disease. Compared with children living with clear air those in Mexico City (MC) exhibit systemic, brain and intrathecal inflammation, low CSF Aβ{sub 42,} breakdown of the BBB, attention and short-term memory deficits, prefrontal white matter hyperintensities, damage to epithelial and endothelial barriers, tight junction and neural autoantibodies, and Alzheimer and Parkinson's hallmarks. The prefrontal white matter is a target of air pollution. We examined by light and electron microscopy the prefrontal white mattermore » of MC dogs (n: 15, age 3.17±0.74 years), children and teens (n: 34, age: 12.64±4.2 years) versus controls. Major findings in MC residents included leaking capillaries and small arterioles with extravascular lipids and erythrocytes, lipofuscin in pericytes, smooth muscle and endothelial cells (EC), thickening of cerebrovascular basement membranes with small deposits of amyloid, patchy absence of the perivascular glial sheet, enlarged Virchow–Robin spaces and nanosize particles (20–48 nm) in EC, basement membranes, axons and dendrites. Tight junctions, a key component of the neurovascular unit (NVU) were abnormal in MC versus control dogs (χ{sup 2}<0.0001), and white matter perivascular damage was significantly worse in MC dogs (p=0.002). The integrity of the NVU, an interactive network of vascular, glial and neuronal cells is compromised in MC young residents. Characterizing the early NVU damage and identifying biomarkers of neurovascular dysfunction may provide a fresh insight into Alzheimer pathogenesis and open opportunities for pediatric neuroprotection. - Highlights: • The prefrontal white matter is a target of air pollution. • Tight junctions, key neurovascular unit elements, are abnormal in young urbanites. • Identifying neurovascular

Upregulation of neurovascular communication through filamin abrogation promotes ectopic periventricular neurogenesis.

PubMed

Houlihan, Shauna L; Lanctot, Alison A; Guo, Yan; Feng, Yuanyi

2016-09-24

Neuronal fate-restricted intermediate progenitors (IPs) are derived from the multipotent radial glia (RGs) and serve as the direct precursors for cerebral cortical neurons, but factors that control their neurogenic plasticity remain elusive. Here we report that IPs' neuron production is enhanced by abrogating filamin function, leading to the generation of periventricular neurons independent of normal neocortical neurogenesis and neuronal migration. Loss of Flna in neural progenitor cells (NPCs) led RGs to undergo changes resembling epithelial-mesenchymal transition (EMT) along with exuberant angiogenesis that together changed the microenvironment and increased neurogenesis of IPs. We show that by collaborating with β-arrestin, Flna maintains the homeostatic signaling between the vasculature and NPCs, and loss of this function results in escalated Vegfa and Igf2 signaling, which exacerbates both EMT and angiogenesis to further potentiate IPs' neurogenesis. These results suggest that the neurogenic potential of IPs may be boosted in vivo by manipulating Flna-mediated neurovascular communication.

Advanced and standardized evaluation of neurovascular compression syndromes

NASA Astrophysics Data System (ADS)

Hastreiter, Peter; Vega Higuera, Fernando; Tomandl, Bernd; Fahlbusch, Rudolf; Naraghi, Ramin

2004-05-01

Caused by a contact between vascular structures and the root entry or exit zone of cranial nerves neurovascular compression syndromes are combined with different neurological diseases (trigeminal neurolagia, hemifacial spasm, vertigo, glossopharyngeal neuralgia) and show a relation with essential arterial hypertension. As presented previously, the semi-automatic segmentation and 3D visualization of strongly T2 weighted MR volumes has proven to be an effective strategy for a better spatial understanding prior to operative microvascular decompression. After explicit segmentation of coarse structures, the tiny target nerves and vessels contained in the area of cerebrospinal fluid are segmented implicitly using direct volume rendering. However, based on this strategy the delineation of vessels in the vicinity of the brainstem and those at the border of the segmented CSF subvolume are critical. Therefore, we suggest registration with MR angiography and introduce consecutive fusion after semi-automatic labeling of the vascular information. Additionally, we present an approach of automatic 3D visualization and video generation based on predefined flight paths. Thereby, a standardized evaluation of the fused image data is supported and the visualization results are optimally prepared for intraoperative application. Overall, our new strategy contributes to a significantly improved 3D representation and evaluation of vascular compression syndromes. Its value for diagnosis and surgery is demonstrated with various clinical examples.

Exploiting neurovascular coupling: a Bayesian sequential Monte Carlo approach applied to simulated EEG fNIRS data

NASA Astrophysics Data System (ADS)

Croce, Pierpaolo; Zappasodi, Filippo; Merla, Arcangelo; Chiarelli, Antonio Maria

2017-08-01

Objective. Electrical and hemodynamic brain activity are linked through the neurovascular coupling process and they can be simultaneously measured through integration of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS). Thanks to the lack of electro-optical interference, the two procedures can be easily combined and, whereas EEG provides electrophysiological information, fNIRS can provide measurements of two hemodynamic variables, such as oxygenated and deoxygenated hemoglobin. A Bayesian sequential Monte Carlo approach (particle filter, PF) was applied to simulated recordings of electrical and neurovascular mediated hemodynamic activity, and the advantages of a unified framework were shown. Approach. Multiple neural activities and hemodynamic responses were simulated in the primary motor cortex of a subject brain. EEG and fNIRS recordings were obtained by means of forward models of volume conduction and light propagation through the head. A state space model of combined EEG and fNIRS data was built and its dynamic evolution was estimated through a Bayesian sequential Monte Carlo approach (PF). Main results. We showed the feasibility of the procedure and the improvements in both electrical and hemodynamic brain activity reconstruction when using the PF on combined EEG and fNIRS measurements. Significance. The investigated procedure allows one to combine the information provided by the two methodologies, and, by taking advantage of a physical model of the coupling between electrical and hemodynamic response, to obtain a better estimate of brain activity evolution. Despite the high computational demand, application of such an approach to in vivo recordings could fully exploit the advantages of this combined brain imaging technology.

Testing the neurovascular hypothesis of Alzheimer's disease: LRP-1 antisense reduces blood-brain barrier clearance, increases brain levels of amyloid-beta protein, and impairs cognition.

PubMed

Jaeger, Laura B; Dohgu, Shinya; Hwang, Mark C; Farr, Susan A; Murphy, M Paul; Fleegal-DeMotta, Melissa A; Lynch, Jessica L; Robinson, Sandra M; Niehoff, Michael L; Johnson, Steven N; Kumar, Vijaya B; Banks, William A

2009-01-01

Decreased clearance is the main reason amyloid-beta protein (Abeta) is increased in the brains of patients with Alzheimer's disease (AD). The neurovascular hypothesis states that this decreased clearance is caused by impairment of low density lipoprotein receptor related protein-1 (LRP-1), the major brain-to-blood transporter of Abeta at the blood-brain barrier (BBB). As deletion of the LRP-1 gene is a lethal mutation, we tested the neurovascular hypothesis by developing a cocktail of phosphorothioate antisenses directed against LRP-1 mRNA. We found these antisenses in comparison to random antisense selectively decreased LRP-1 expression, reduced BBB clearance of Abeta42, increased brain levels of Abeta42, and impaired learning ability and recognition memory in mice. These results support dysfunction of LRP-1 at the BBB as a mechanism by which brain levels of Abeta could increase and AD would be promoted.

Cerebral Vascular Disease and Neurovascular Injury in Ischemic Stroke

PubMed Central

Hu, Xiaoming; De Silva, T. Michael; Chen, Jun; Faraci, Frank M.

2017-01-01

The consequences of cerebrovascular disease are among the leading health issues worldwide. Large and small cerebral vessel disease can trigger stroke and contribute to the vascular component of other forms of neurological dysfunction and degeneration. Both forms of vascular disease are driven by diverse risk factors, with hypertension as the leading contributor. Despite the importance of neurovascular disease and subsequent injury following ischemic events, fundamental knowledge in these areas lag behind our current understanding of neuroprotection and vascular biology in general. The goal of this review is to address select key structural and functional changes in the vasculature that promote hypoperfusion and ischemia, while also affecting the extent of injury and effectiveness of therapy. In addition, as damage to the blood-brain barrier (BBB) is one of the major consequences of ischemia, we discuss cellular and molecular mechanisms underlying ischemia-induced changes in BBB integrity and function, including alterations in endothelial cells and the contribution of pericytes, immune cells, and matrix metalloproteinases. Identification of cell types, pathways, and molecules that control vascular changes before and after ischemia may result in novel approaches to slow the progression of cerebrovascular disease and lessen both the frequency and impact of ischemic events. PMID:28154097

Microstructured Thin Film Nitinol for a Neurovascular Flow-Diverter

NASA Astrophysics Data System (ADS)

Chen, Yanfei; Howe, Connor; Lee, Yongkuk; Cheon, Seongsik; Yeo, Woon-Hong; Chun, Youngjae

2016-03-01

A cerebral aneurysm occurs as a result of a weakened blood vessel, which allows blood to flow into a sac or a ballooned section. Recent advancement shows that a new device, ‘flow-diverter’, can divert blood flow away from the aneurysm sac. People found that a flow-diverter based on thin film nitinol (TFN), works very effectively, however there are no studies proving the mechanical safety in irregular, curved blood vessels. Here, we study the mechanical behaviors and structural safety of a novel microstructured TFN membrane through the computational and experimental studies, which establish the fundamental aspects of stretching and bending mechanics of the structure. The result shows a hyper-elastic behavior of the TFN with a negligible strain change up to 180° in bending and over 500% in radial stretching, which is ideal in the use in neurovascular curved arteries. The simulation determines the optimal joint locations between the TFN and stent frame. In vitro experimental test qualitatively demonstrates the mechanical flexibility of the flow-diverter with multi-modal bending. In vivo micro X-ray and histopathology study demonstrate that the TFN can be conformally deployed in the curved blood vessel of a swine model without any significant complications or abnormalities.

Cerebral Vascular Disease and Neurovascular Injury in Ischemic Stroke.

PubMed

Hu, Xiaoming; De Silva, T Michael; Chen, Jun; Faraci, Frank M

2017-02-03

The consequences of cerebrovascular disease are among the leading health issues worldwide. Large and small cerebral vessel disease can trigger stroke and contribute to the vascular component of other forms of neurological dysfunction and degeneration. Both forms of vascular disease are driven by diverse risk factors, with hypertension as the leading contributor. Despite the importance of neurovascular disease and subsequent injury after ischemic events, fundamental knowledge in these areas lag behind our current understanding of neuroprotection and vascular biology in general. The goal of this review is to address select key structural and functional changes in the vasculature that promote hypoperfusion and ischemia, while also affecting the extent of injury and effectiveness of therapy. In addition, as damage to the blood-brain barrier is one of the major consequences of ischemia, we discuss cellular and molecular mechanisms underlying ischemia-induced changes in blood-brain barrier integrity and function, including alterations in endothelial cells and the contribution of pericytes, immune cells, and matrix metalloproteinases. Identification of cell types, pathways, and molecules that control vascular changes before and after ischemia may result in novel approaches to slow the progression of cerebrovascular disease and lessen both the frequency and impact of ischemic events. © 2017 American Heart Association, Inc.

Microstructured Thin Film Nitinol for a Neurovascular Flow-Diverter

PubMed Central

Chen, Yanfei; Howe, Connor; Lee, Yongkuk; Cheon, Seongsik; Yeo, Woon-Hong; Chun, Youngjae

2016-01-01

A cerebral aneurysm occurs as a result of a weakened blood vessel, which allows blood to flow into a sac or a ballooned section. Recent advancement shows that a new device, ‘flow-diverter’, can divert blood flow away from the aneurysm sac. People found that a flow-diverter based on thin film nitinol (TFN), works very effectively, however there are no studies proving the mechanical safety in irregular, curved blood vessels. Here, we study the mechanical behaviors and structural safety of a novel microstructured TFN membrane through the computational and experimental studies, which establish the fundamental aspects of stretching and bending mechanics of the structure. The result shows a hyper-elastic behavior of the TFN with a negligible strain change up to 180° in bending and over 500% in radial stretching, which is ideal in the use in neurovascular curved arteries. The simulation determines the optimal joint locations between the TFN and stent frame. In vitro experimental test qualitatively demonstrates the mechanical flexibility of the flow-diverter with multi-modal bending. In vivo micro X-ray and histopathology study demonstrate that the TFN can be conformally deployed in the curved blood vessel of a swine model without any significant complications or abnormalities. PMID:27009500

Long-Term Outcomes of Using Hyaluronic Acid-Carboxymethylcellulose Adhesion Barrier Film on the Neurovascular Bundle.

PubMed

Patel, Rutveej; Modi, Parth K; Elsamra, Sammy E; Kim, Isaac Yi

2016-06-01

We hypothesize that the use of hyaluronic acid-carboxymethylcellulose (HACM) adhesion barrier at the neurovascular bundle may hasten the return of erectile function after robot-assisted laparoscopic prostatectomy. A retrospective review identified 462 consecutive patients who underwent a nerve-sparing prostatectomy between 2009 and 2012. The first 246 patients were administered the barrier film, while the next 216 patients, the control group, did not receive HACM. Postoperative erectile function and oncologic outcomes were compared. Independent t-test and Kaplan-Meier analysis were conducted, p < 0.05 was considered significant. The two groups were well matched, without significant differences in age, weight, operative time, prostate size, preoperative prostate-specific antigen, sexual health inventory for men (SHIM), or AUA symptom scores. The mean SHIM was significantly higher for the experimental group at 6 months (6.39 vs 4.75, p = 0.008), 9 months (7.32 vs 5.44, p = 0.006), 1 year (8.52 vs 6.90, p = 0.049), and 18 months (10.01 vs 7.60, p = 0.018). This effect was not noted beyond 18 months. A subgroup analysis of patients with initial SHIM scores 22 or greater demonstrated a higher rate of return to the preoperative SHIM score for the barrier film group, 23% vs 12% (p = 0.046). There was no significant difference in biochemical recurrence between groups, with a median follow-up duration of 18 months. HACM application at the neurovascular bundle during prostatectomy may decrease the time to return of erectile function, with improved SHIM at 6 to 18 months after surgery. This effect is more pronounced in patients with better baseline erectile function. There is no significant effect on biochemical recurrence.

A Working Module for the Neurovascular Unit in the Sexually Dimorphic Nucleus of the Preoptic Area.

PubMed

He, Zhen; Cui, Li; Ferguson, Sherry A; Paule, Merle G

2018-01-01

The neurovascular unit (NVU) can be conceptualized as a functional entity consisting of neurons, astrocytes, pericytes, and endothelial and smooth muscle cells that operate in concert to affect blood flow to a very circumscribed area. Although we are currently in a "golden era" of bioengineering, there are, as yet, no living NVUs-on-a-chip modules available and the development of a neural chip that would mimic NVUs is a seemingly lofty goal. The sexually dimorphic nucleus of the preoptic area (SDN-POA) is a tiny brain structure (between 0.001~0.007 mm 3 in rats) with an assessable biological function (i.e., male sexual behavior). The present effort was undertaken to determine whether there are identifiable NVUs in the SDN-POA by assessing its vasculature relative to its known neural components. First, a thorough and systematic review of thousands of histologic and immunofluorescent images from 201 weanling and adult rats was undertaken to define the characteristics of the vessels supplying the SDN-POA: its primary supply artery/arteriole and capillaries are physically inseparable from their neural elements. A subsequent immunofluorescent study targeting α-smooth muscle actin confirmed the identity of an artery/arteriole supplying the SDN-POA. In reality, the predominant components of the SDN-POA are calbindin D28k-positive neurons that are comingled with tyrosine hydroxylase-positive projections. Finally, a schematic of an SDN-POA NVU is proposed as a working model of the basic building block of the CNS. Such modules could serve the study of neurovascular mechanisms and potentially inform the development of next generation bioengineered neural transplants, i.e., the construct of an NVU neural chip.

Computational and Pharmacological Target of Neurovascular Unit for Drug Design and Delivery

PubMed Central

2015-01-01

The blood-brain barrier (BBB) is a dynamic and highly selective permeable interface between central nervous system (CNS) and periphery that regulates the brain homeostasis. Increasing evidences of neurological disorders and restricted drug delivery process in brain make BBB as special target for further study. At present, neurovascular unit (NVU) is a great interest and highlighted topic of pharmaceutical companies for CNS drug design and delivery approaches. Some recent advancement of pharmacology and computational biology makes it convenient to develop drugs within limited time and affordable cost. In this review, we briefly introduce current understanding of the NVU, including molecular and cellular composition, physiology, and regulatory function. We also discuss the recent technology and interaction of pharmacogenomics and bioinformatics for drug design and step towards personalized medicine. Additionally, we develop gene network due to understand NVU associated transporter proteins interactions that might be effective for understanding aetiology of neurological disorders and new target base protective therapies development and delivery. PMID:26579539

Comparison between whole-body and head and neck neurovascular coils for 3-T magnetic resonance proton resonance frequency shift thermography guidance in the head and neck region.

PubMed

Ginat, Daniel Thomas; Anthony, Gregory J; Christoforidis, Gregory; Oto, Aytekin; Dalag, Leonard; Sammet, Steffen

2018-02-01

The purpose of this study is to compare the image quality of magnetic resonance (MR) treatment planning images and proton resonance frequency (PRF) shift thermography images and inform coil selection for MR-guided laser ablation of tumors in the head and neck region. Laser ablation was performed on an agar phantom and monitored via MR PRF shift thermography on a 3-T scanner, following acquisition of T1-weighted (T1W) planning images. PRF shift thermography images and T2-weighted (T2W) planning images were also performed in the neck region of five normal human volunteers. Signal-to-noise ratios (SNR) and temperature uncertainty were calculated and compared between scans acquired with the quadrature mode body integrated coil and a head and neck neurovascular coil. T1W planning images of the agar phantom produced SNRs of 4.0 and 12.2 for the quadrature mode body integrated coil and head and neck neurovascular coil, respectively. The SNR of the phantom MR thermography magnitude images obtained using the quadrature mode body integrated coil was 14.4 versus 59.6 using the head and neck coil. The average temperature uncertainty for MR thermography performed on the phantom with the quadrature mode body integrated coil was 1.1 versus 0.3 °C with the head and neck coil. T2W planning images of the neck in five human volunteers produced SNRs of 28.3 and 91.0 for the quadrature mode body integrated coil and head and neck coil, respectively. MR thermography magnitude images of the neck in the volunteers obtained using the quadrature mode body integrated coil had a signal-to-noise ratio of 8.3, while the SNR using the head and neck coil was 16.1. The average temperature uncertainty for MR thermography performed on the volunteers with the body coil was 2.5 versus 1.6 °C with the head and neck neurovascular coil. The quadrature mode body integrated coil provides inferior image quality for both basic treatment planning sequences and MR PRF shift thermography compared with a

Interventional Radiology Clinical Practice Guideline Recommendations for Neurovascular Disorders Are Not Based on High-Quality Systematic Reviews.

PubMed

Chong, A B; Taylor, M; Schubert, G; Vassar, M

2017-04-01

In recent years, clinical practice guidelines have been criticized for biased interpretations of research evidence, and interventional radiology is no exception. Our aim was to evaluate the methodologic quality and transparency of reporting in systematic reviews used as evidence in interventional radiology clinical practice guidelines for neurovascular disorders from the Society of Interventional Radiology. Our sources were 9 neurovascular disorder clinical practice guidelines from the Society of Interventional Radiology. We selected 65 systematic reviews and meta-analyses. A Measurement Tool to Assess Systematic Reviews (AMSTAR) and Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) tools were used to assess the methodologic quality and reporting transparency of systematic reviews. Radial plots were created on the basis of average scores for PRISMA and AMSTAR items. On the basis of AMSTAR scores, 3 (4.62%) reviews were high-quality, 28 reviews (43.08%) were moderate-quality, and 34 reviews (52.31%) were low-quality, with an average quality score of 3.66 (34.32%; minimum, 0%; maximum, 81.82%). The average PRISMA score was 18.18 (69.41%). We were unable to obtain previous versions for 8 reviews, 7 of which were from the Cochrane Database of Systematic Reviews. The methodologic quality of systematic reviews needs to be improved. Although reporting clarity was much better than the methodologic quality, it still has room for improvement. The methodologic quality and transparency of reporting did not vary much among clinical practice guidelines. This study can also be applied to other medical specialties to examine the quality of studies used as evidence in their own clinical practice guidelines. © 2017 by American Journal of Neuroradiology.

Imaging the Perivascular Space as a Potential Biomarker of Neurovascular and Neurodegenerative Diseases.

PubMed

Ramirez, Joel; Berezuk, Courtney; McNeely, Alicia A; Gao, Fuqiang; McLaurin, JoAnne; Black, Sandra E

2016-03-01

Although the brain lacks conventional lymphatic vessels found in peripheral tissue, evidence suggests that the space surrounding the vasculature serves a similar role in the clearance of fluid and metabolic waste from the brain. With aging, neurodegeneration, and cerebrovascular disease, these microscopic perivascular spaces can become enlarged, allowing for visualization and quantification on structural MRI. The purpose of this review is to: (i) describe some of the recent pre-clinical findings from basic science that shed light on the potential neurophysiological mechanisms driving glymphatic and perivascular waste clearance, (ii) review some of the pathobiological etiologies that may lead to MRI-visible enlarged perivascular spaces (ePVS), (iii) describe the possible clinical implications of ePVS, (iv) evaluate existing qualitative and quantitative techniques used for measuring ePVS burden, and (v) propose future avenues of research that may improve our understanding of this potential clinical neuroimaging biomarker for fluid and metabolic waste clearance dysfunction in neurodegenerative and neurovascular diseases.

Regulation of cerebrospinal fluid (CSF) flow in neurodegenerative, neurovascular and neuroinflammatory disease

PubMed Central

Simon, Matthew J.; Iliff, Jeffrey J.

2015-01-01

Cerebrospinal fluid (CSF) circulation and turnover provides a sink for the elimination of solutes from the brain interstitium, serving an important homeostatic role for the function of the central nervous system. Disruption of normal CSF circulation and turnover is believed to contribute to the development of many diseases, including neurodegenerative conditions such as Alzheimer’s disease, ischemic and traumatic brain injury, and neuroinflammatory conditions such as multiple sclerosis. Recent insights into CSF biology suggesting that CSF and interstitial fluid exchange along a brain-wide network of perivascular spaces termed the ‘glymphatic’ system suggest that CSF circulation may interact intimately with glial and vascular function to regulate basic aspects of brain function. Dysfunction within this glial vascular network, which is a feature of the aging and injured brain, is a potentially critical link between brain injury, neuroinflammation and the development of chronic neurodegeneration. Ongoing research within this field may provide a powerful new framework for understanding the common links between neurodegenerative, neurovascular and neuroinflammatory disease, in addition to providing potentially novel therapeutic targets for these conditions. PMID:26499397

EEG-NIRS based assessment of neurovascular coupling during anodal transcranial direct current stimulation--a stroke case series.

PubMed

Dutta, Anirban; Jacob, Athira; Chowdhury, Shubhajit Roy; Das, Abhijit; Nitsche, Michael A

2015-04-01

A method for electroencephalography (EEG) - near-infrared spectroscopy (NIRS) based assessment of neurovascular coupling (NVC) during anodal transcranial direct current stimulation (tDCS). Anodal tDCS modulates cortical neural activity leading to a hemodynamic response, which was used to identify impaired NVC functionality. In this study, the hemodynamic response was estimated with NIRS. NIRS recorded changes in oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) concentrations during anodal tDCS-induced activation of the cortical region located under the electrode and in-between the light sources and detectors. Anodal tDCS-induced alterations in the underlying neuronal current generators were also captured with EEG. Then, a method for the assessment of NVC underlying the site of anodal tDCS was proposed that leverages the Hilbert-Huang Transform. The case series including four chronic (>6 months) ischemic stroke survivors (3 males, 1 female from age 31 to 76) showed non-stationary effects of anodal tDCS on EEG that correlated with the HbO2 response. Here, the initial dip in HbO2 at the beginning of anodal tDCS corresponded with an increase in the log-transformed mean-power of EEG within 0.5Hz-11.25Hz frequency band. The cross-correlation coefficient changed signs but was comparable across subjects during and after anodal tDCS. The log-transformed mean-power of EEG lagged HbO2 response during tDCS but then led post-tDCS. This case series demonstrated changes in the degree of neurovascular coupling to a 0.526 A/m(2) square-pulse (0-30 s) of anodal tDCS. The initial dip in HbO2 needs to be carefully investigated in a larger cohort, for example in patients with small vessel disease.

Foe or friend? Janus-faces of the neurovascular unit in the formation of brain metastases.

PubMed

Wilhelm, Imola; Fazakas, Csilla; Molnár, Kinga; Végh, Attila G; Haskó, János; Krizbai, István A

2018-04-01

Despite the potential obstacle represented by the blood-brain barrier for extravasating malignant cells, metastases are more frequent than primary tumors in the central nervous system. Not only tightly interconnected endothelial cells can hinder metastasis formation, other cells of the brain microenvironment (like astrocytes and microglia) can also be very hostile, destroying the large majority of metastatic cells. However, malignant cells that are able to overcome these harmful mechanisms may benefit from the shielding and even support provided by cerebral endothelial cells, astrocytes and microglia, rendering the brain a sanctuary site against anti-tumor strategies. Thus, cells of the neurovascular unit have a Janus-faced attitude towards brain metastatic cells, being both destructive and protective. In this review, we present the main mechanisms of brain metastasis formation, including those involved in extravasation through the brain vasculature and survival in the cerebral environment.

Stability in neurovascular function at 3800m.

PubMed

Caldwell, Hannah G; Ainslie, Philip N; Ellis, Lindsay A; Phillips, Aaron A; Flück, Daniela

2017-12-01

Hypoxia-induced neurocognitive impairments have been of clinical interest for centuries. The mechanisms responsible for these neurocognitive impairments at altitude are unclear, but may relate to the uncoupling of local neural activity with appropriate changes in cerebral blood flow (CBF; i.e., functional hyperemia). At both sea level and following 3 and 7days at 3800m (Barcroft Research Lab, White Mountain, CA, USA), transcranial Doppler was used to index CBF during three separate tasks designed to evoke cerebral functional hyperemia in 11 healthy individuals (26.6±5.5yrs, 2 females). The tasks were: 1) Visual stimulation (VS), with measurement of anterior and posterior CBF; 2) Verbal fluency (VF), with measurement of bilateral CBF; and 3) Visuospatial task (VST), with measurement of bilateral CBF. The VS evoked an increase from baseline to percent peak response in both the posterior (15.2±7.7%, P<0.01) and anterior (7.6±3.5%, P<0.01) cerebral hemispheres; however, the percent peak response was higher in the posterior brain, where visual regions are localized (P=0.01). The left-sided task, VF, resulted in an increase in both the left (12.2±4.0%, P<0.01) and right (9.0±4.4%, P<0.01) cerebral hemispheres; however, the percent peak response was higher in the left brain, where language centers are located (P<0.01). The right-sided task, VST, evoked an increase in both the left (13.9±7.1%, P<0.01) and right (16.8±6.7%, P<0.01) cerebral hemispheres; however, the percent peak response was higher in the right brain, where visuospatial regions are located (P<0.01). Each cerebral functional hyperemia response for all three tasks was unaffected by high altitude exposure (P>0.05). Overall, at least at 3800m, neurovascular function is intact with exposure to 3 and 7days of high altitude and likely does not explain the previous reports of neurocognitive impairment. Copyright © 2017 Elsevier Inc. All rights reserved.

The neurovascular relation in oxygen-induced retinopathy.

PubMed

Akula, James D; Mocko, Julie A; Benador, Ilan Y; Hansen, Ronald M; Favazza, Tara L; Vyhovsky, Tanya C; Fulton, Anne B

2008-01-01

Longitudinal studies in rat models of retinopathy of prematurity (ROP) have demonstrated that abnormalities of retinal vasculature and function change hand-in-hand. In the developing retina, vascular and neural structures are under cooperative molecular control. In this study of rats with oxygen-induced retinopathy (OIR) models of ROP, mRNA expression of vascular endothelial growth factor (VEGF), semaphorin (Sema), and their neuropilin receptor (NRP) were examined during the course of retinopathy to evaluate their roles in the observed neurovascular congruency. Oxygen exposures designed to induce retinopathy were delivered to Sprague-Dawley rat pups (n=36) from postnatal day (P) 0 to P14 or from P7 to P14. Room-air-reared controls (n=18) were also studied. Sensitivities of the rod photoreceptors (S(rod)) and the postreceptor cells (Sm) were derived from electroretinographic (ERG) records. Arteriolar tortuosity, T(A), was derived from digital fundus images using Retinal Image multi-Scale Analysis (RISA) image analysis software. mRNA expression of VEGF(164), semaphorin IIIA (Sema3A), and neuropilin-1 (NRP-1) was evaluated by RT-PCR of retinal extracts. Tests were performed at P15-P16, P18-P19, and P25-P26. Relations among ERG, RISA, and PCR parameters were evaluated using linear regression on log transformed data. Sm was low and T(A) was high at young ages, then both resolved by P25-P26. VEGF(164) and Sema3A mRNA expression were also elevated early and decreased with age. Low Sm was significantly associated with high VEGF(164) and Sema3A expression. Low S(rod) was also significantly associated with high VEGF(164). S(rod) and Sm were both correlated with T(A). NRP-1 expression was little affected by OIR. The postreceptor retina appears to mediate the vascular abnormalities that characterize OIR. Because of the relationships revealed by these data, early treatment that targets the neural retina may mitigate the effects of ROP.

The neurovascular relation in oxygen-induced retinopathy

PubMed Central

Akula, James D.; Mocko, Julie A.; Benador, Ilan Y.; Hansen, Ronald M.; Favazza, Tara L.; Vyhovsky, Tanya C.

2008-01-01

Purpose Longitudinal studies in rat models of retinopathy of prematurity (ROP) have demonstrated that abnormalities of retinal vasculature and function change hand-in-hand. In the developing retina, vascular and neural structures are under cooperative molecular control. In this study of rats with oxygen-induced retinopathy (OIR) models of ROP, mRNA expression of vascular endothelial growth factor (VEGF), semaphorin (Sema), and their neuropilin receptor (NRP) were examined during the course of retinopathy to evaluate their roles in the observed neurovascular congruency. Methods Oxygen exposures designed to induce retinopathy were delivered to Sprague-Dawley rat pups (n=36) from postnatal day (P) 0 to P14 or from P7 to P14. Room-air-reared controls (n=18) were also studied. Sensitivities of the rod photoreceptors (Srod) and the postreceptor cells (Sm) were derived from electroretinographic (ERG) records. Arteriolar tortuosity, TA, was derived from digital fundus images using Retinal Image multi-Scale Analysis (RISA) image analysis software. mRNA expression of VEGF164, semaphorin IIIA (Sema3A), and neuropilin-1 (NRP-1) was evaluated by RT–PCR of retinal extracts. Tests were performed at P15–P16, P18–P19, and P25–P26. Relations among ERG, RISA, and PCR parameters were evaluated using linear regression on log transformed data. Results Sm was low and TA was high at young ages, then both resolved by P25–P26. VEGF164 and Sema3A mRNA expression were also elevated early and decreased with age. Low Sm was significantly associated with high VEGF164 and Sema3A expression. Low Srod was also significantly associated with high VEGF164. Srod and Sm were both correlated with TA. NRP-1 expression was little affected by OIR. Conclusions The postreceptor retina appears to mediate the vascular abnormalities that characterize OIR. Because of the relationships revealed by these data, early treatment that targets the neural retina may mitigate the effects of ROP. PMID:19112532

Measurement of neurovascular coupling in human motor cortex using simultaneous transcranial doppler (TCD) and electroencephalography (EEG).

PubMed

Alam, Monzurul; Ahmed, Ghazanfar; Ling, Yan To; Zheng, Yong-Ping

2018-05-25

Event-related desynchronization (ERD) is a relative power decrease of electroencephalogram (EEG) signals in a specific frequency band during physical motor execution, while transcranial Doppler (TCD) measures cerebral blood flow velocity. The objective of this study was to investigate the neurovascular coupling in the motor cortex by using an integrated EEG and TCD system, and to find any difference in hemodynamic responses in healthy young male and female adults. Approach: 30 healthy volunteers, aged 20-30 years were recruited for this study. The subjects were asked to perform a motor task for the duration of a provided visual cue. Simultaneous EEG and TCD recording was carried out using a new integrated system to detect the ERD arising from the EEG signals, and to measure the mean blood flow velocity of the left and right middle cerebral arteries from bilateral TCD signals. Main Results: The results showed a significant decrease in EEG power in mu band (7.5-12.5 Hz) during the motor task compared to the resting phase. It showed significant increase in desynchronization on the contralateral side of the motor task compared to the ipsilateral side. Mean blood flow velocity during the task phase was significantly higher in comparison with the resting phase at the contralateral side. The results also showed a significantly higher increase in the percentage of mean blood flow velocity in the contralateral side of motor task compared to the ipsilateral side. However, no significant difference in desynchronization, or change of mean blood flow velocity was found between males and females. Significance: A combined TCD-EEG system successfully detects ERD and blood flow velocity in cerebral arteries, and can be used as a useful tool to study neurovascular coupling in the brain. There is no significant difference in the hemodynamic responses in healthy young males and females. © 2018 Institute of Physics and Engineering in Medicine.

Regulation of Neurovascular Coupling in Autoimmunity to Water and Ion Channels

PubMed Central

Jukkola, Peter; Gu, Chen

2014-01-01

Much progress has been made in understanding autoimmune channelopathies, but the underlying pathogenic mechanisms are not always clear due to broad expression of some channel proteins. Recent studies show that autoimmune conditions that interfere with neurovascular coupling in the central nervous system (CNS) can lead to neurodegeneration. Cerebral blood flow that meets neuronal activity and metabolic demand is tightly regulated by local neural activity. This process of reciprocal regulation involves coordinated actions of a number of cell types, including neurons, glia, and vascular cells. In particular, astrocytic endfeet cover more than 90% of brain capillaries to assist blood-brain barrier (BBB) function, and wrap around synapses and nodes of Ranvier to communicate with neuronal activity. In this review, we highlight four types of channel proteins that are expressed in astrocytes, regarding their structures, biophysical properties, expression and distribution patterns, and related diseases including autoimmune disorders. Water channel aquaporin 4 (AQP4) and inwardly-rectifying potassium (Kir4.1) channels are concentrated in astrocytic endfeet, whereas some voltage-gated Ca2+ and two-pore-domain K+ channels are expressed throughout the cell body of reactive astrocytes. More channel proteins are found in astrocytes under normal and abnormal conditions. This research field will contribute to a better understanding of pathogenic mechanisms underlying autoimmune disorders. PMID:25462580

Model of the transient neurovascular response based on prompt arterial dilation

PubMed Central

Kim, Jung Hwan; Khan, Reswanul; Thompson, Jeffrey K; Ress, David

2013-01-01

Brief neural stimulation results in a stereotypical pattern of vascular and metabolic response that is the basis for popular brain-imaging methods such as functional magnetic resonance imagine. However, the mechanisms of transient oxygen transport and its coupling to cerebral blood flow (CBF) and oxygen metabolism (CMRO2) are poorly understood. Recent experiments show that brief stimulation produces prompt arterial vasodilation rather than venous vasodilation. This work provides a neurovascular response model for brief stimulation based on transient arterial effects using one-dimensional convection–diffusion transport. Hemoglobin oxygen dissociation is included to enable predictions of absolute oxygen concentrations. Arterial CBF response is modeled using a lumped linear flow model, and CMRO2 response is modeled using a gamma function. Using six parameters, the model successfully fit 161/166 measured extravascular oxygen time courses obtained for brief visual stimulation in cat cerebral cortex. Results show how CBF and CMRO2 responses compete to produce the observed features of the hemodynamic response: initial dip, hyperoxic peak, undershoot, and ringing. Predicted CBF and CMRO2 response amplitudes are consistent with experimental measurements. This model provides a powerful framework to quantitatively interpret oxygen transport in the brain; in particular, its intravascular oxygen concentration predictions provide a new model for fMRI responses. PMID:23756690

Proposal of landmarks for clamping neurovascular elements during endoscopic surgery of the supraglottic region.

PubMed

Souvirón, R; Maranillo, E; Vázquez, T; Patel, N; McHanwell, S; Cobeta, I; Scola, B; Sañudo, J

2013-01-01

Bleeding within the supraglottic region can be a lethal complication after CO(2) laser microsurgery. Our aim was to propose endoluminal anatomical landmarks to locate the superior laryngeal vessels resulting in a safer microsurgery. Endoluminal dissections were made in 22 larynges without laryngeal disease. The neurovascular structures were in the superior third of a triangle defined by the vocal process, the anterior commissure, and the epiglottic attachment of the aryepiglottic fold. They overlapped in 4 different ways: pattern I (70.4%): superior laryngeal vein (SLV), superior laryngeal artery (SLA), and internal laryngeal nerve (ILN); pattern II (13.6%): SLA, SLV, ILN; pattern III (4.6%): SLV, ILN, and SLA; pattern IV (4.6%): SLA, ILN, and SLV. Microsurgery in the supraglottic region may be safer if surgeons are aware of the superior third of the above-defined triangle, "danger area", where the vascular elements of this region are located. Copyright © 2012 Wiley Periodicals, Inc.

CD44 expression in endothelial colony-forming cells regulates neurovascular trophic effect

PubMed Central

Sakimoto, Susumu; Marchetti, Valentina; Aguilar, Edith; Lee, Kelsey; Usui, Yoshihiko; Bucher, Felicitas; Trombley, Jennifer K.; Fallon, Regis; Wagey, Ravenska; Peters, Carrie; Scheppke, Elizabeth L.; Westenskow, Peter D.

2017-01-01

Vascular abnormalities are a common component of eye diseases that often lead to vision loss. Vaso-obliteration is associated with inherited retinal degenerations, since photoreceptor atrophy lowers local metabolic demands and vascular support to those regions is no longer required. Given the degree of neurovascular crosstalk in the retina, it may be possible to use one cell type to rescue another cell type in the face of severe stress, such as hypoxia or genetically encoded cell-specific degenerations. Here, we show that intravitreally injected human endothelial colony-forming cells (ECFCs) that can be isolated and differentiated from cord blood in xeno-free media collect in the vitreous cavity and rescue vaso-obliteration and neurodegeneration in animal models of retinal disease. Furthermore, we determined that a subset of the ECFCs was more effective at anatomically and functionally preventing retinopathy; these cells expressed high levels of CD44, the hyaluronic acid receptor, and IGFBPs (insulin-like growth factor–binding proteins). Injection of cultured media from ECFCs or only recombinant human IGFBPs also rescued the ischemia phenotype. These results help us to understand the mechanism of ECFC-based therapies for ischemic insults and retinal neurodegenerative diseases. PMID:28138561

Pathobiology of tobacco smoking and neurovascular disorders: untied strings and alternative products.

PubMed

Naik, Pooja; Cucullo, Luca

2015-10-31

Tobacco smoke (TS) is the leading cause of preventable deaths worldwide. In addition to a host of well characterized diseases including chronic obstructive pulmonary disease, oral and peripheral cancers and cardiovascular complications, epidemiological evidence suggests that chronic smokers are at equal risk to develop neurological and neurovascular complications such as multiple sclerosis, Alzheimer's disease, stroke, vascular dementia and small vessel ischemic disease (SVID). Unfortunately, few direct neurotoxicology studies of tobacco smoking and its pathogenic pathways have been produced so far. A major link between TS and CNS disorders is the blood-brain barrier (BBB). In this review article, we summarize the current understanding of the toxicological impact of TS on BBB physiology and function and major compensatory mechanisms such as nrf2- ARE signaling and anti-inflammatory pathways activated by TS. In the same context, we discuss the controversial role of antioxidant supplementation as a prophylactic and/or therapeutic approach in delaying or decreasing the disease complications in smokers. Further, we cover a number of toxicological studies associated with "reduced exposure" cigarette products including electronic cigarettes. Finally, we provide insights on possible avenues for future research including mechanistic studies using direct inhalation rodent models.

Comparison between cone-beam and multislice computed tomography depicting mandibular neurovascular canal structures.

PubMed

Naitoh, Munetaka; Nakahara, Kino; Suenaga, Yutaka; Gotoh, Kenichi; Kondo, Shintaro; Ariji, Eiichiro

2010-01-01

The most common diagnostic imaging modalities for cross-sectional imaging in dental implant planning are currently cone-beam computed tomography (CBCT) and multislice CT (MSCT). However, clinical differences between CBCT and MSCT in this task have not been fully clarified. In this investigation, the detection of fine anatomical structures in the mandible was assessed and compared between CBCT and MSCT images. The sample consisted of 28 patients who had undergone CBCT and MSCT. The bifid mandibular canal in the mandibular ramus, accessory mental and buccal foramina, and median and lateral lingual bony canals were observed in 2-D images, and the findings were compared between CBCT and MSCT. Four of 19 canals observed in CBCT were not observed in MSCT images. Three accessory mental foramina in 2 patients and 28 lateral lingual bony canals in 18 patients were observed consistently using the two methods. Depiction of fine anatomic features in the mandible associated with neurovascular structures is consistent between CBCT and MSCT images. Copyright 2010 Mosby, Inc. All rights reserved.

Neurovascular stent artifacts in 3D-TOF and 3D-PCMRI: Influence of stent design on flow measurement.

PubMed

Bouillot, Pierre; Brina, Olivier; Delattre, Bénédicte M A; Ouared, Rafik; Pellaton, Alain; Yilmaz, Hasan; Machi, Paolo; Lovblad, Karl-Olof; Farhat, Mohamed; Pereira, Vitor Mendes; Vargas, Maria Isabel

2018-06-12

The morphological and hemodynamic evaluations of neurovascular diseases treated with stents would benefit from noninvasive imaging techniques such as 3D time-of-flight MRI (3D-TOF) and 3D phase contrast MRI (3D-PCMRI). For this purpose, a comprehensive evaluation of the stent artifacts and their impact on the flow measurement is critical. The artifacts of a representative sample of neurovascular stents were evaluated in vitro with 3D-TOF and 3D-PCMRI sequences. The dependency of the artifacts with respect to the orientation was analyzed for each stent design as well as the impact on the flow measurement accuracy. Furthermore, the 3D-PCMRI data of four patients carrying intracranial aneurysms treated with flow diverter stents were analyzed as illustrative examples. The stent artifacts were mainly confined to the stent lumen therefore indicating the leading role of shielding effect. The influence of the stent design and its orientation with respect to the transmitting MR coils were highlighted. The artifacts impacted the 3D-PCMRI velocities mainly in the low magnitude domains, which were discarded from the analysis ensuring reliable near-stent velocities. The feasibility of in-stent flow measurements was confirmed in vivo on two patients who showed strong correlation between flow and geometric features. In two other patients, the consistency of out-of-stent velocities was verified qualitatively through intra-aneurysmal streamlines except when susceptibility artifacts occurred. The present results motivate the conception of low inductance or nonconductive stent design. Furthermore, the feasibility of near-stent 3D-PCMRI measurements opens the door to clinical applications like the post-treatment follow-up of stenoses or intracranial aneurysms. © 2018 International Society for Magnetic Resonance in Medicine.

Neurovascular Network Explorer 2.0: A Simple Tool for Exploring and Sharing a Database of Optogenetically-evoked Vasomotion in Mouse Cortex In Vivo.

PubMed

Uhlirova, Hana; Tian, Peifang; Kılıç, Kıvılcım; Thunemann, Martin; Sridhar, Vishnu B; Chmelik, Radim; Bartsch, Hauke; Dale, Anders M; Devor, Anna; Saisan, Payam A

2018-05-04

The importance of sharing experimental data in neuroscience grows with the amount and complexity of data acquired and various techniques used to obtain and process these data. However, the majority of experimental data, especially from individual studies of regular-sized laboratories never reach wider research community. A graphical user interface (GUI) engine called Neurovascular Network Explorer 2.0 (NNE 2.0) has been created as a tool for simple and low-cost sharing and exploring of vascular imaging data. NNE 2.0 interacts with a database containing optogenetically-evoked dilation/constriction time-courses of individual vessels measured in mice somatosensory cortex in vivo by 2-photon microscopy. NNE 2.0 enables selection and display of the time-courses based on different criteria (subject, branching order, cortical depth, vessel diameter, arteriolar tree) as well as simple mathematical manipulation (e.g. averaging, peak-normalization) and data export. It supports visualization of the vascular network in 3D and enables localization of the individual functional vessel diameter measurements within vascular trees. NNE 2.0, its source code, and the corresponding database are freely downloadable from UCSD Neurovascular Imaging Laboratory website 1 . The source code can be utilized by the users to explore the associated database or as a template for databasing and sharing their own experimental results provided the appropriate format.

Dexamethasone Rescues Neurovascular Unit Integrity from Cell Damage Caused by Systemic Administration of Shiga Toxin 2 and Lipopolysaccharide in Mice Motor Cortex

PubMed Central

Pinto, Alipio; Jacobsen, Mariana; Geoghegan, Patricia A.; Cangelosi, Adriana; Cejudo, María Laura; Tironi-Farinati, Carla; Goldstein, Jorge

2013-01-01

Shiga toxin 2 (Stx2)-producing Escherichia coli (STEC) causes hemorrhagic colitis and hemolytic uremic syndrome (HUS) that can lead to fatal encephalopathies. Neurological abnormalities may occur before or after the onset of systemic pathological symptoms and motor disorders are frequently observed in affected patients and in studies with animal models. As Stx2 succeeds in crossing the blood-brain barrier (BBB) and invading the brain parenchyma, it is highly probable that the observed neurological alterations are based on the possibility that the toxin may trigger the impairment of the neurovascular unit and/or cell damage in the parenchyma. Also, lipopolysaccharide (LPS) produced and secreted by enterohemorrhagic Escherichia coli (EHEC) may aggravate the deleterious effects of Stx2 in the brain. Therefore, this study aimed to determine (i) whether Stx2 affects the neurovascular unit and parenchymal cells, (ii) whether the contribution of LPS aggravates these effects, and (iii) whether an inflammatory event underlies the pathophysiological mechanisms that lead to the observed injury. The administration of a sub-lethal dose of Stx2 was employed to study in detail the motor cortex obtained from a translational murine model of encephalopathy. In the present paper we report that Stx2 damaged microvasculature, caused astrocyte reaction and neuronal degeneration, and that this was aggravated by LPS. Dexamethasone, an anti-inflammatory, reversed the pathologic effects and proved to be an important drug in the treatment of acute encephalopathies. PMID:23894578

Distribution of temperature changes and neurovascular coupling in rat brain following 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") exposure.

PubMed

Coman, Daniel; Sanganahalli, Basavaraju G; Jiang, Lihong; Hyder, Fahmeed; Behar, Kevin L

2015-10-01

(+/-)3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") is an abused psychostimulant that produces strong monoaminergic stimulation and whole-body hyperthermia. MDMA-induced thermogenesis involves activation of uncoupling proteins (UCPs), primarily a type specific to skeletal muscle (UCP-3) and absent from the brain, although other UCP types are expressed in the brain (e.g. thalamus) and might contribute to thermogenesis. Since neuroimaging of brain temperature could provide insights into MDMA action, we measured spatial distributions of systemically administered MDMA-induced temperature changes and dynamics in rat cortex and subcortex using a novel magnetic resonance method, Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), with an exogenous temperature-sensitive probe (thulium ion and macrocyclic chelate 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethyl-1,4,7,10-tetraacetate (DOTMA(4-))). The MDMA-induced temperature rise was greater in the cortex than in the subcortex (1.6 ± 0.4 °C versus 1.3 ± 0.4 °C) and occurred more rapidly (2.0 ± 0.2 °C/h versus 1.5 ± 0.2 °C/h). MDMA-induced temperature changes and dynamics in the cortex and body were correlated, although the body temperature exceeded the cortex temperature before and after MDMA. Temperature, neuronal activity, and blood flow (CBF) were measured simultaneously in the cortex and subcortex (i.e. thalamus) to investigate possible differences of MDMA-induced warming across brain regions. MDMA-induced warming correlated with increases in neuronal activity and blood flow in the cortex, suggesting that the normal neurovascular response to increased neural activity was maintained. In contrast to the cortex, a biphasic relationship was seen in the subcortex (i.e. thalamus), with a decline in CBF as temperature and neural activity rose, transitioning to a rise in CBF for temperature above 37 °C, suggesting that MDMA affected CBF and neurovascular coupling differently in subcortical regions

Regulation of cerebrospinal fluid (CSF) flow in neurodegenerative, neurovascular and neuroinflammatory disease.

PubMed

Simon, Matthew J; Iliff, Jeffrey J

2016-03-01

Cerebrospinal fluid (CSF) circulation and turnover provides a sink for the elimination of solutes from the brain interstitium, serving an important homeostatic role for the function of the central nervous system. Disruption of normal CSF circulation and turnover is believed to contribute to the development of many diseases, including neurodegenerative conditions such as Alzheimer's disease, ischemic and traumatic brain injury, and neuroinflammatory conditions such as multiple sclerosis. Recent insights into CSF biology suggesting that CSF and interstitial fluid exchange along a brain-wide network of perivascular spaces termed the 'glymphatic' system suggest that CSF circulation may interact intimately with glial and vascular function to regulate basic aspects of brain function. Dysfunction within this glial vascular network, which is a feature of the aging and injured brain, is a potentially critical link between brain injury, neuroinflammation and the development of chronic neurodegeneration. Ongoing research within this field may provide a powerful new framework for understanding the common links between neurodegenerative, neurovascular and neuroinflammatory disease, in addition to providing potentially novel therapeutic targets for these conditions. This article is part of a Special Issue entitled: Neuro Inflammation edited by Helga E. de Vries and Markus Schwaninger. Copyright © 2015 Elsevier B.V. All rights reserved.

Iron transport across the blood-brain barrier; Development, neurovascular regulation and cerebral amyloid angiopathy

PubMed Central

McCarthy, Ryan C; Kosman, Daniel J

2014-01-01

There are two barriers for iron entry into the brain: 1) the brain-cerebrospinal fluid (CSF) barrier and 2) the blood-brain barrier (BBB). Here, we review the literature on developmental iron accumulation by the brain, focusing on the transport of iron through the brain microvascular endothelial cells (BMVEC) of the BBB. We review the iron trafficking proteins which may be involved in the iron flux across BMVEC and discuss the plausible mechanisms of BMVEC iron uptake and efflux. We suggest a model for how BMVEC iron uptake and efflux are regulated and a mechanism by which the majority of iron is trafficked across the developing BBB under the direct guidance of neighboring astrocytes. Thus, we place brain iron uptake in the context of the neurovascular unit of the adult brain. Last, we propose that BMVEC iron is involved in the aggregation of amyloid-β peptides leading to the progression of cerebral amyloid angiopathy which often occurs prior to dementia and the onset of Alzheimer's disease. PMID:25355056

Three-Dimensional Blood-Brain Barrier Model for in vitro Studies of Neurovascular Pathology

NASA Astrophysics Data System (ADS)

Cho, Hansang; Seo, Ji Hae; Wong, Keith H. K.; Terasaki, Yasukazu; Park, Joseph; Bong, Kiwan; Arai, Ken; Lo, Eng H.; Irimia, Daniel

2015-10-01

Blood-brain barrier (BBB) pathology leads to neurovascular disorders and is an important target for therapies. However, the study of BBB pathology is difficult in the absence of models that are simple and relevant. In vivo animal models are highly relevant, however they are hampered by complex, multi-cellular interactions that are difficult to decouple. In vitro models of BBB are simpler, however they have limited functionality and relevance to disease processes. To address these limitations, we developed a 3-dimensional (3D) model of BBB on a microfluidic platform. We verified the tightness of the BBB by showing its ability to reduce the leakage of dyes and to block the transmigration of immune cells towards chemoattractants. Moreover, we verified the localization at endothelial cell boundaries of ZO-1 and VE-Cadherin, two components of tight and adherens junctions. To validate the functionality of the BBB model, we probed its disruption by neuro-inflammation mediators and ischemic conditions and measured the protective function of antioxidant and ROCK-inhibitor treatments. Overall, our 3D BBB model provides a robust platform, adequate for detailed functional studies of BBB and for the screening of BBB-targeting drugs in neurological diseases.

[The importance of the thermometric method for assessing the function of mucoperiosteal flaps in uranostaphyloplasty with/without transection of the neurovascular bundles in the rehabilitation of patients with congenital cleft palate].

PubMed

Bernadskiĭ, Iu I; Khar'kov, L V; Prudnikov, V M

1990-01-01

The nature and degree of reflow to the mucoperiosteal flaps was evaluated using a distant thermometry of the cleft palate in 67 children under uranostaphyloplasty and in early postsurgical period. In extracting the neurovascular bundles from their channels heat reflow to the palate was more fast and pronounced than with the bundles sectioned.

Distribution of temperature changes and neurovascular coupling in rat brain following 3,4-methylenedioxymethamphetamine (MDMA,‘ecstasy’) exposure

PubMed Central

Coman, Daniel; Sanganahalli, Basavaraju G.; Jiang, Lihong; Hyder, Fahmeed; Behar, Kevin L.

2015-01-01

(+/−)3,4-methylenedioxymethamphetamine (MDMA, ‘ecstasy’) is an abused psychostimulant producing strong monoaminergic stimulation and whole-body hyperthermia. MDMA-induced thermogenesis involves activation of uncoupling proteins (UCP), primarily a type specific to skeletal muscle (UCP-3) and which is absent in brain, although other UCP types are expressed in brain (e.g., thalamus) and might contribute to thermogenesis. Since neuroimaging of brain temperature could provide insights of MDMA action, we measured spatial distributions of systemically-administered MDMA-induced temperature changes and dynamics in rat cortex and subcortex using a novel magnetic resonance method, Biosensor Imaging of Redundant Deviation of Shifts (BIRDS), with an exogenous temperature-sensitive probe (thulium ion and macrocyclic chelate 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethyl-1,4,7,10-tetraacetate (DOTMA4−)). The MDMA-induced temperature rise in cortex was greater than in subcortex (1.6±0.4°C vs. 1.3±0.4°C) and occurred more rapidly (2.0±0.2°C/h vs. 1.5±0.2°C/h). MDMA-induced temperature changes and dynamics in cortex and body were correlated, although body temperature exceeded cortex before and after MDMA. Temperature, neuronal activity, and blood flow (CBF) were measured simultaneously in cortex and subcortex (i.e., thalamus) to investigate possible differences of MDMA-induced warming across brain regions. MDMA-induced warming correlated with increases in neuronal activity and blood flow in cortex, suggesting that the normal neurovascular response to increased neural activity was maintained. In contrast to cortex, a biphasic relationship was seen in subcortex (i.e., thalamus), with a decline in CBF as temperature and neural activity rose, transitioning to a rise in CBF for temperature >37°C, suggesting that MDMA affected CBF and neurovascular coupling differently in subcortical regions. Considering that MDMA effects on CBF and heat dissipation (as well as

Use of patient specific 3D printed neurovascular phantoms to evaluate the clinical utility of a high resolution x-ray imager

NASA Astrophysics Data System (ADS)

Setlur Nagesh, S. V.; Russ, M.; Ionita, C. N.; Bednarek, D.; Rudin, S.

2017-03-01

Modern 3D printing technology can fabricate vascular phantoms based on an actual human patient with a high degree of precision facilitating a realistic simulation environment for an intervention. We present two experimental setups using 3D printed patient-specific neurovasculature to simulate different disease anatomies. To simulate the human neurovasculature in the Circle of Willis, patient-based phantoms with aneurysms were 3D printed using a Objet Eden 260V printer. Anthropomorphic head phantoms and a human skull combined with acrylic plates simulated human head bone anatomy and x-ray attenuation. For dynamic studies the 3D printed phantom was connected to a pulsatile flow loop with the anthropomorphic phantom underneath. By combining different 3D printed phantoms and the anthropomorphic phantoms, different patient pathologies can be simulated. For static studies a 3D printed neurovascular phantom was embedded inside a human skull and used as a positional reference for treatment devices such as stents. To simulate tissue attenuation acrylic layers were added. Different combinations can simulate different patient treatment procedures. The Complementary-Metal-Oxide-Semiconductor (CMOS) based High Resolution Fluoroscope (HRF) with 75μm pixels offers an advantage over the state-of-the-art 200 μm pixel Flat Panel Detector (FPD) due to higher Nyquist frequency and better DQE performance. Whether this advantage is clinically useful during an actual clinical neurovascular intervention can be addressed by qualitatively evaluating images from a cohort of various cases performed using both detectors. The above-mentioned method can offer a realistic substitute for an actual clinical procedure. Also a large cohort of cases can be generated and used for a HRF clinical utility determination study.

Delayed Docosahexaenoic Acid Treatment Combined with Dietary Supplementation of Omega-3 Fatty Acids Promotes Long-Term Neurovascular Restoration After Ischemic Stroke.

PubMed

Pu, Hongjian; Jiang, Xiaoyan; Hu, Xiaoming; Xia, Jinchao; Hong, Dandan; Zhang, Wenting; Gao, Yanqin; Chen, Jun; Shi, Yejie

2016-12-01

Prophylactic dietary intake of omega-3 polyunsaturated fatty acids (n-3 PUFAs) has been shown to remarkably ameliorate ischemic brain injury. However, the therapeutic efficacy of n-3 PUFA administration post-stroke, especially its impact on neurovascular remodeling and long-term neurological recovery, has not been fully characterized thus far. In this study, we investigated the effect of n-3 PUFA supplementation, as well as in combination with docosahexaenoic acid (DHA) injections, on long-term stroke outcomes. Mice were subjected to transient middle cerebral artery occlusion (MCAO) before randomly assigned to four groups to receive the following: (1) low dose of n-3 PUFAs as the vehicle control, (2) intraperitoneal DHA injections, (3) n-3 PUFA dietary supplement, or (4) combined treatment of (2) and (3). Neurological deficits and brain atrophy, neurogenesis, angiogenesis, and glial scar formation were assessed up to 28 days after MCAO. Results revealed that groups 2 and 3 showed only marginal reduction in post-stroke tissue loss and attenuation of cognitive deficits. Interestingly, group 4 exhibited significantly reduced tissue atrophy and improved cognitive functions compared to groups 2 and 3 with just a single treatment. Mechanistically, the combined treatment promoted post-stroke neurogenesis and angiogenesis, as well as reduced glial scar formation, all of which significantly correlated with the improved spatial memory in the Morris water maze. These results demonstrate an effective therapeutic regimen to enhance neurovascular restoration and long-term cognitive recovery in the mouse model of MCAO. Combined post-stroke DHA treatment and n-3 PUFA dietary supplementation thus may be a potential clinically translatable therapy for stroke or related brain disorders.

NADPH-diaphorase activity and neurovascular coupling in the rat cerebral cortex.

PubMed

Vlasenko, O V; Maisky, V A; Maznychenko, A V; Pilyavskii, A I

2008-01-01

The distribution of NADPH-diaphorase-reactive (NADPH-dr) neurons and neuronal processes in the cerebral cortex and basal forebrain and their association with parenchymal vessels were studied in normal adult rats using NADPH-d histochemical protocol. The intensely stained cortical interneurons and reactive subcortically originating afferents, and stained microvessels were examined through a light microscope at law (x250) and high (x630) magnifications. NADPH-dr interneurons were concentrated in layers 2-6 of the M1 and M2 areas. However, clear predominance in their concentration (14 +/- 0.8 P < 0.05 per section) was found in layer 6. A mean number of labeled neurons in auditory (AuV), granular and agranular (GI, AIP) areas of the insular cortex was calculated to reach 12.3 +/- 0.7, 18.5 +/- 1.0 and 23.3 +/- 1.7 units per section, respectively (P < 0.05). The distinct apposition of labelled neurons to intracortical vessels was found in the M1, M2. The order of frequency of neurovascular coupling in different zones of the cerebral cortex was as following sequence: AuV (31.2%, n = 1040) > GI (18.0%, n = 640) > S1 (13.3%, n = 720) > M1 (6.3%, n = 1360). A large number of structural associations between labeled cells and vessels in the temporal and insular cortex indicate that NADPH-d-reactive interneurons can contribute to regulation of the cerebral regional blood flow in these areas.

The role of neuroinflammation and neurovascular dysfunction in major depressive disorder.

PubMed

Jeon, Sang Won; Kim, Yong-Ku

2018-01-01

Although depression has generally been explained with monoamine theory, it is far more multifactorial, and therapies that address the disease's pathway have not been developed. In this context, an understanding of neuroinflammation and neurovascular dysfunction would enable a more comprehensive approach to depression. Inflammation is in a sense a type of allostatic load involving the immune, endocrine, and nervous systems. Neuroinflammation is involved in the pathophysiology of depression by increasing proinflammatory cytokines, activating the hypothalamus-pituitary-adrenal axis, increasing glucocorticoid resistance, and affecting serotonin synthesis and metabolism, neuronal apoptosis and neurogenesis, and neuroplasticity. In future, identifying the subtypes of depression with increased vulnerability to inflammation and testing the effects of inflammatory modulating agents in these patient groups through clinical trials will lead to more concrete conclusions on the matter. The vascular depression hypothesis is supported by evidence for the association between vascular disease and late-onset depression and between ischemic brain lesions and distinctive depressive symptoms. Vascular depression may be the entity most suitable for studies of the mechanisms of depression. Pharmacotherapies used in the prevention and treatment of cerebrovascular disease may help prevent vascular depression. In future, developments in structural and functional imaging, electrophysiology, chronobiology, and genetics will reveal the association between depression and brain lesions. This article aims to give a general review of the existing issues examined in the literature pertaining to depression-related neuroinflammatory and vascular functions, related pathophysiology, applicability to depression treatment, and directions for future research.

The role of neuroinflammation and neurovascular dysfunction in major depressive disorder

PubMed Central

Jeon, Sang Won; Kim, Yong-Ku

2018-01-01

Although depression has generally been explained with monoamine theory, it is far more multifactorial, and therapies that address the disease’s pathway have not been developed. In this context, an understanding of neuroinflammation and neurovascular dysfunction would enable a more comprehensive approach to depression. Inflammation is in a sense a type of allostatic load involving the immune, endocrine, and nervous systems. Neuroinflammation is involved in the pathophysiology of depression by increasing proinflammatory cytokines, activating the hypothalamus–pituitary–adrenal axis, increasing glucocorticoid resistance, and affecting serotonin synthesis and metabolism, neuronal apoptosis and neurogenesis, and neuroplasticity. In future, identifying the subtypes of depression with increased vulnerability to inflammation and testing the effects of inflammatory modulating agents in these patient groups through clinical trials will lead to more concrete conclusions on the matter. The vascular depression hypothesis is supported by evidence for the association between vascular disease and late-onset depression and between ischemic brain lesions and distinctive depressive symptoms. Vascular depression may be the entity most suitable for studies of the mechanisms of depression. Pharmacotherapies used in the prevention and treatment of cerebrovascular disease may help prevent vascular depression. In future, developments in structural and functional imaging, electrophysiology, chronobiology, and genetics will reveal the association between depression and brain lesions. This article aims to give a general review of the existing issues examined in the literature pertaining to depression-related neuroinflammatory and vascular functions, related pathophysiology, applicability to depression treatment, and directions for future research. PMID:29773951

Cerebrovascular reactivity and neurovascular coupling in patients with obstructive sleep apnea.

PubMed

Tekgol Uzuner, G; Uzuner, N

2017-01-01

Obstructive sleep apnea syndrome (OSAS) has been implicated as an independent risk factor for stroke. There are data suggesting the presence of lower cerebrovascular reactivity (CVR) as determined by transcranial Doppler (TCD) in patients with OSAS. We concurrently investigated neurovascular coupling (NVC) with visual stimulation, and CVR using breath-holding (BH) test on TCD in patients with OSAS. Data were collected in 49 patients with moderate to severe OSAS, and compared to 15 healthy subjects matched for age and risk factors. The CVR to hypercapnia was measured by BH test, and the NVC was performed with visual stimulation. There were no significant differences in baseline characteristics of patients and controls, except for BMI, which was significantly higher in patients with OSAS (p = 0.036). OSAS patients showed significantly lower reactivity during BH in comparison to controls (36.9% ± 14.0% vs. 46.6% ± 20.1%; p = 0.019). The reactivity time was also significantly shorter in the OSAS group (8.0 ± 4.2 s) when compared to controls (10.1 ± 4.3 s; p = 0.015). The visual stimulation produced similar reactivity in patients (27.7% ± 9.4%) and controls (29.1 ± 13.9; p > 0.05). Our data demonstrate a diminished vasodilator response capacity only to a strong stimulator such as hypercapnia in OSAS patients. However, the NVC, as shown by the TCD, is quite normal, suggesting that a weak or mild stimulation produces a proper reactivity among OSAS patients.

Use of patient specific 3D printed (3DP) neurovascular phantoms for mechanical assessment of devices used in image guided minimally invasive procedures

NASA Astrophysics Data System (ADS)

Tabaczynski, Janelle R.; Stoll, Thomas; Shepard, Lauren; Siddiqui, Mohamed I. G.; Karkhanis, Nitant V.; Sommer, Kelsey; Siddiqui, Adnan H.; Ionita, Ciprian N.

2018-03-01

Patient-specific 3D printed phantoms (3DP) can reproduce accurate patient geometry and provide precise tools for Endovascular Image Guided Interventions (EIGI) simulations. We propose to build and test 3DP phantoms which mimic the arterial wall elasticity and surface properties and demonstrate their utility in comprehensive EIGI simulations. 3DP idealized and patient specific vascular phantoms were manufactured using Stratasys Objet 500 Connex 3. The idealized phantoms were created using a sine wave shape, patient specific phantoms were based on CT- angiography volumes. The phantoms were coated with a hydrophilic material to mimic vascular surface properties. We tested various endovascular procedures using an Interventional Device Testing Equipment (IDTE) 2000 and measured push/pull force used to actuate endovascular devices during EIGIs. The force needed to advance devices in neurovascular phantoms varied based on tortuosity, material and coating, ranging from -3 to 21 grams-force. Hydrophilic coating reduced maximum force from 21 to 4.8 grams-force in the same model. IDTE 2000 results of neurovascular models were compared to hand manipulation of guidewire access using a six-axis force sensor with forces ranging from -50 to 440 grams. The clot retriever tested in carotid models experienced most friction around tortuous bends ranging from -65 to -90 grams-force, with increasing rigidity of materials creating increased friction. Sine wave model forces varied from -2 to 105 grams. 3DP allows manufacturing of vascular phantoms with precise mechanical and surface properties which can be used for EIGI simulations for imaging protocol optimization and device behavior assessment.

Aquaporin-4 Functionality and Virchow-Robin Space Water Dynamics: Physiological Model for Neurovascular Coupling and Glymphatic Flow

PubMed Central

Kwee, Ingrid L.

2017-01-01

The unique properties of brain capillary endothelium, critical in maintaining the blood-brain barrier (BBB) and restricting water permeability across the BBB, have important consequences on fluid hydrodynamics inside the BBB hereto inadequately recognized. Recent studies indicate that the mechanisms underlying brain water dynamics are distinct from systemic tissue water dynamics. Hydrostatic pressure created by the systolic force of the heart, essential for interstitial circulation and lymphatic flow in systemic circulation, is effectively impeded from propagating into the interstitial fluid inside the BBB by the tightly sealed endothelium of brain capillaries. Instead, fluid dynamics inside the BBB is realized by aquaporin-4 (AQP-4), the water channel that connects astrocyte cytoplasm and extracellular (interstitial) fluid. Brain interstitial fluid dynamics, and therefore AQP-4, are now recognized as essential for two unique functions, namely, neurovascular coupling and glymphatic flow, the brain equivalent of systemic lymphatics. PMID:28820467

Aquaporin-4 Functionality and Virchow-Robin Space Water Dynamics: Physiological Model for Neurovascular Coupling and Glymphatic Flow.

PubMed

Nakada, Tsutomu; Kwee, Ingrid L; Igarashi, Hironaka; Suzuki, Yuji

2017-08-18

The unique properties of brain capillary endothelium, critical in maintaining the blood-brain barrier (BBB) and restricting water permeability across the BBB, have important consequences on fluid hydrodynamics inside the BBB hereto inadequately recognized. Recent studies indicate that the mechanisms underlying brain water dynamics are distinct from systemic tissue water dynamics. Hydrostatic pressure created by the systolic force of the heart, essential for interstitial circulation and lymphatic flow in systemic circulation, is effectively impeded from propagating into the interstitial fluid inside the BBB by the tightly sealed endothelium of brain capillaries. Instead, fluid dynamics inside the BBB is realized by aquaporin-4 (AQP-4), the water channel that connects astrocyte cytoplasm and extracellular (interstitial) fluid. Brain interstitial fluid dynamics, and therefore AQP-4, are now recognized as essential for two unique functions, namely, neurovascular coupling and glymphatic flow, the brain equivalent of systemic lymphatics.

A three-dimensional study of the musculotendinous and neurovascular architecture of the gracilis muscle: application to functional muscle transfer.

PubMed

Fattah, A Y; Ravichandiran, K; Zuker, R M; Agur, A M R

2013-09-01

Muscle transfer is used to restore function typically using a single vector of contraction. Although its use with two independently functional muscular units has been employed, in order to refine this concept we endeavoured to detail the intramuscular anatomy of gracilis, a muscle commonly used for transfer. A novel method to capture intramuscular fibre bundle and neurovascular arrangement was used to create a three-dimensional (3D) digital model that allowed for accurate representation of the relationships between all the intramuscular structures to facilitate flap planning. Twenty gracilis muscles were harvested from 15 cadavers. All components of the muscle were digitised using a Microscribe G2 Digitiser. The data were exported to the 3D animation software Autodesk(®) Maya(®) 2012 whereupon it was rendered into a 3D model that can be exported as static images or videos. Neurovascular anatomy and muscle architecture were analysed from these models, and fibre bundle length, pennation angle and physiological cross-sectional area were calculated from digitised data. The muscle is composed of a variable number of distinct longitudinal segments with muscle fibres spiralling onto the tendon. The main artery to the muscle has three main intramuscular patterns of distribution. The venae comitantes drain discrete zones without intramuscular macroscopic anastomoses. The minor pedicles form an anastomotic chain along the anterior border of the muscle and all vessels were biased to the deep surface. The nerve is related to the vessels in a variable manner and both run between longitudinal muscular compartments. The digitisation technique may be used to advance knowledge of intramuscular architecture and it demonstrated that the gracilis muscle is comprised of four to seven muscular compartments, each representing a functional unit that may theoretically be differentially activated and could be harnessed for more sophisticated muscle transfers. Copyright © 2013 British

Nrf2 Deficiency Exacerbates Obesity-Induced Oxidative Stress, Neurovascular Dysfunction, Blood-Brain Barrier Disruption, Neuroinflammation, Amyloidogenic Gene Expression, and Cognitive Decline in Mice, Mimicking the Aging Phenotype.

PubMed

Tarantini, Stefano; Valcarcel-Ares, M Noa; Yabluchanskiy, Andriy; Tucsek, Zsuzsanna; Hertelendy, Peter; Kiss, Tamas; Gautam, Tripti; Zhang, Xin A; Sonntag, William E; de Cabo, Rafael; Farkas, Eszter; Elliott, Michael H; Kinter, Michael T; Deak, Ferenc; Ungvari, Zoltan; Csiszar, Anna

2018-06-14

Obesity has deleterious effects on cognitive function in the elderly adults. In mice, aging exacerbates obesity-induced oxidative stress, microvascular dysfunction, blood-brain barrier (BBB) disruption, and neuroinflammation, which compromise cognitive health. However, the specific mechanisms through which aging and obesity interact to remain elusive. Previously, we have shown that Nrf2 signaling plays a critical role in microvascular resilience to obesity and that aging is associated with progressive Nrf2 dysfunction, promoting microvascular impairment. To test the hypothesis that Nrf2 deficiency exacerbates cerebromicrovascular dysfunction induced by obesity Nrf2+/+ and Nrf2-/-, mice were fed an adipogenic high-fat diet (HFD). Nrf2 deficiency significantly exacerbated HFD-induced oxidative stress and cellular senescence, impairment of neurovascular coupling responses, BBB disruption, and microglia activation, mimicking the aging phenotype. Obesity in Nrf2-/- mice elicited complex alterations in the amyloidogenic gene expression profile, including upregulation of amyloid precursor protein. Nrf2 deficiency and obesity additively reduced long-term potentiation in the CA1 area of the hippocampus. Collectively, Nrf2 dysfunction exacerbates the deleterious effects of obesity, compromising cerebromicrovascular and brain health by impairing neurovascular coupling mechanisms, BBB integrity and synaptic function and promoting neuroinflammation. These results support a possible role for age-related Nrf2 dysfunction in the pathogenesis of vascular cognitive impairment and Alzheimer's disease.

Foucher first dorsal metacarpal artery flap versus littler heterodigital neurovascular flap in resurfacing thumb pulp loss defects.

PubMed

Delikonstantinou, Iraklis P; Gravvanis, Andreas I; Dimitriou, Vasilios; Zogogiannis, Ioannis; Douma, Amalia; Tsoutsos, Dimosthenis A

2011-08-01

Our study aims to illustrate the advantages and disadvantages of Foucher's first dorsal metacarpal artery flap and Littler's heterodigital neurovascular flap in thumb pulp reconstruction, by assessing wound healing of donor and recipient sites, sensibility, and functional outcome of the reconstructed thumb. Fourteen male patients were reconstructed either with Foucher (n = 8) or Littler flap (n = 6). Dissection of Foucher's flap was faster than that of Littler's flap. All Littler flaps survived completely, but we experienced 1 partial Foucher flap necrosis. Thumb motility and stability was optimal in all patients. Wound healing of donor sites was achieved in both groups. Two patients reconstructed with Littler flap developed scar contractures and presented a reduced range of motion of donor finger and first webspace, respectively. Although Littler flap resulted in better sensibility and tactile gnosis of the reconstructed thumb-pulp, Foucher flap ensured negligible donor site morbidity, complete cortical reorientation, and better overall hand function.

Effects of dominant and non-dominant passive arm manoeuvres on the neurovascular coupling response.

PubMed

Llwyd, Osian; Panerai, Ronney B; Robinson, Thompson G

2017-11-01

Models designed to study neurovascular coupling (NVC) describe a possible cerebral hemisphere dominance dependent on task completed and preference in handedness. We investigated whether passive arm manoeuvre performed with dominant (Dom-Arm) or non-dominant arm (ND-Arm) stimulated haemodynamic differences in either contralateral (Cont-H) or ipsilateral (Ipsil-H) cerebral hemisphere. Healthy individuals lying in supine position, had measurements of beat-to-beat blood pressure (BP, mmHg), electrocardiogram (HR, bpm), end-tidal CO 2 (etCO 2 , mmHg), and bilateral insonation of the middle cerebral arteries (MCA, cm s -1 ). Arm movement was performed for 60 s with passive flexion and extension of the elbow (1 Hz), before manoeuvre was repeated on other arm. Data were normalised and effect of treatment was analysed for differences between manoeuvres and within each time period. Seventeen (eight males) healthy volunteers, aged 56 ± 7 years, were studied. Dom-Arm and ND-Arm manoeuvres stimulated a comparable temporal response in peripheral and cerebral haemodynamic parameters between Cont-H and Ipsil-H. Both manoeuvres can be used to evoke similar bilateral MCA responses in assessing NVC. This finding should lead to more efficient protocols when using passive arm movement for NVC studies in healthy subjects.

Aging Exacerbates Obesity-induced Cerebromicrovascular Rarefaction, Neurovascular Uncoupling, and Cognitive Decline in Mice

PubMed Central

Tucsek, Zsuzsanna; Toth, Peter; Tarantini, Stefano; Sosnowska, Danuta; Gautam, Tripti; Warrington, Junie P.; Giles, Cory B.; Wren, Jonathan D.; Koller, Akos; Ballabh, Praveen; Sonntag, William E.; Csiszar, Anna

2014-01-01

Epidemiological studies show that obesity has deleterious effects on the brain and cognitive function in the elderly population. However, the specific mechanisms through which aging and obesity interact to promote cognitive decline remain unclear. To test the hypothesis that aging exacerbates obesity-induced cerebromicrovascular impairment, we compared young (7 months) and aged (24 months) high-fat diet–fed obese C57BL/6 mice. We found that aging exacerbates the obesity-induced decline in microvascular density both in the hippocampus and in the cortex. The extent of hippocampal microvascular rarefaction and the extent of impairment of hippocampal-dependent cognitive function positively correlate. Aging exacerbates obesity-induced loss of pericyte coverage on cerebral microvessels and alters hippocampal angiogenic gene expression signature, which likely contributes to microvascular rarefaction. Aging also exacerbates obesity-induced oxidative stress and induction of NADPH oxidase and impairs cerebral blood flow responses to whisker stimulation. Collectively, obesity exerts deleterious cerebrovascular effects in aged mice, promoting cerebromicrovascular rarefaction and neurovascular uncoupling. The morphological and functional impairment of the cerebral microvasculature in association with increased blood–brain barrier disruption and neuroinflammation (Tucsek Z, Toth P, Sosnowsk D, et al. Obesity in aging exacerbates blood–brain barrier disruption, neuroinflammation and oxidative stress in the mouse hippocampus: effects on expression of genes involved in beta-amyloid generation and Alzheimer’s disease. J Gerontol Biol Med Sci. 2013. In press, PMID: 24269929) likely contribute to obesity-induced cognitive decline in aging. PMID:24895269

Neurovascular Response during Exercise and Mental Stress in Anabolic Steroid Users.

PubMed

Porello, Rafael Armani; Dos Santos, Marcelo Rodrigues; DE Souza, Francis Ribeiro; DA Fonseca, Guilherme Wesley Peixoto; Sayegh, Ana Luiza Carrari; DE Oliveira, Tiago Franco; Akiho, César Abreu; Yonamine, Maurício; Pereira, Rosa Maria Rodrigues; Negrão, Carlos Eduardo; Alves, Maria-Janieire DE Nazaré Nunes

2018-03-01

Increased resting muscle sympathetic nerve activity (MSNA) and lower forearm blood flow (FBF) were observed in young men who use anabolic androgenic steroids (AAS). However, the response of MSNA and FBF in AAS users triggered by muscle mechanoreflex and central command has never been tested. In addition, we evaluated the blood pressure (BP) and heart rate (HR) responses during these maneuvers. Nineteen AAS users (AASU) 31 ± 6 yr of age and 18 AAS nonusers (AASNU) 29 ± 4 yr of age were recruited. All participants were involved in strength training. AAS use was determined using a urine test (liquid chromatography with tandem mass spectrometry). MSNA was measured using the microneurography technique. FBF was measured by using venous occlusion plethysmography. BP was measured using an automatic oscillometric device. HR was recorded continuously through ECG. Isometric handgrip exercise was performed at 30% of the maximal voluntary contraction for 3 min, and mental stress was elicited by the Stroop color-word test for 4 min. The MSNA and FBF responses during exercise were similar between AASU and AASNU, with a trend toward higher MSNA (bursts per minute; P = 0.084) and lower forearm vascular conductance (FVC; units; P = 0.084) in AASU than in AASNU. During mental stress, AASU showed a significantly higher MSNA (P < 0.05) and lower FBF (P < 0.05) compared with AASNU. During both maneuvers, HR and BP increased linearly in both groups; however, AASU showed a significantly higher HR compared with AASNU. During muscle mechanoreflex activation (isometric exercise), AASU have normal MSNA and FBF responses, whereas during central command (mental stress) stimulation, AASU have exacerbated MSNA and blunted vasodilation. Therefore, mental stress seems to exacerbate neurovascular control throughout stress reaction situations in AASU.

Synchronized Astrocytic Ca2+ Responses in Neurovascular Coupling during Somatosensory Stimulation and for the Resting State.

PubMed

Gu, Xiaochun; Chen, Wei; Volkow, Nora D; Koretsky, Alan P; Du, Congwu; Pan, Yingtian

2018-06-26

The role of astrocytes in neurovascular coupling (NVC) is unclear. Here, we applied a multimodality imaging approach to concomitantly measure synchronized neuronal or astrocytic Ca 2+ and hemodynamic changes in the mouse somatosensory cortex at rest and during sensory electrical stimulation. Strikingly, we found that low-frequency stimulation (0.3-1 Hz), which consistently evokes fast neuronal Ca 2+ transients (6.0 ± 2.7 ms latency) that always precede vascular responses, does not always elicit astrocytic Ca 2+ transients (313 ± 65 ms latency). However, the magnitude of the hemodynamic response is increased when astrocytic transients occur, suggesting a facilitatory role of astrocytes in NVC. High-frequency stimulation (5-10 Hz) consistently evokes a large, delayed astrocytic Ca 2+ accumulation (3.48 ± 0.09 s latency) that is temporarily associated with vasoconstriction, suggesting a role for astrocytes in resetting NVC. At rest, neuronal, but not astrocytic, Ca 2+ fluctuations correlate with hemodynamic low-frequency oscillations. Taken together, these results support a role for astrocytes in modulating, but not triggering, NVC. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Improving neurovascular outcomes with bilateral forepaw stimulation in a rat photothrombotic ischemic stroke model

PubMed Central

Liao, Lun-De; Bandla, Aishwarya; Ling, Ji Min; Liu, Yu-Hang; Kuo, Li-Wei; Chen, You-Yin; King, Nicolas KK; Lai, Hsin-Yi; Lin, Yan-Ren; Thakor, Nitish V.

2014-01-01

Abstract. Restoring perfusion to the penumbra during the hyperacute phase of ischemic stroke is a key goal of neuroprotection. Thrombolysis is currently the only approved treatment for ischemic stroke. However, its use is limited by the narrow therapeutic window and side effect of bleeding. Therefore, other interventions are desired that could potentially increase the perfusion of the penumbra. Here, we hypothesized that bilateral peripheral electrical stimulation will improve cerebral perfusion and restore cortical neurovascular response. We assess the outcomes of bilateral forepaw electrical stimulation at intensities of 2 and 4 mA, administered either unilaterally or bilaterally. We developed a combined electrocorticogram (ECoG)-functional photoacoustic microscopy (fPAM) system to evaluate the relative changes in cerebral hemodynamic function and electrophysiologic response to acute, focal stroke. The fPAM system is used for cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) and the ECoG for neural activity, namely somatosensory-evoked potential (SSEP), interhemispheric coherence, and alpha-delta ratio (ADR) in response to forepaw stimulation. Our results confirmed the neuroprotective effect of bilateral forepaw stimulation at 2 mA as indicated by the 82% recovery of ADR and 95% improvement in perfusion into the region of penumbra. This experimental model can be used to study other potential interventions such as therapeutic hypertension and hypercarbia. PMID:26157965

Active, passive, and motor imagery paradigms: component analysis to assess neurovascular coupling.

PubMed

Salinet, Angela S M; Robinson, Thompson G; Panerai, Ronney B

2013-05-15

The association between neural activity and cerebral blood flow (CBF) has been used to assess neurovascular coupling (NVC) in health and diseases states, but little attention has been given to the contribution of simultaneous changes in peripheral covariates. We used an innovative approach to assess the contributions of arterial blood pressure (BP), PaCO2, and the stimulus itself to changes in CBF velocities (CBFv) during active (MA), passive (MP), and motor imagery (MI) paradigms. Continuous recordings of CBFv, beat-to-beat BP, heart rate, and breath-by-breath end-tidal CO2 (EtCO2) were performed in 17 right-handed subjects before, during, and after motor-cognitive paradigms performed with the right arm. A multivariate autoregressive-moving average model was used to calculate the separate contributions of BP, EtCO2, and the neural activation stimulus (represented by a metronome on-off signal) to the CBFv response during paradigms. Differences were found in the bilateral CBFv responses to MI compared with MA and MP, due to the contributions of stimulation (P < 0.05). BP was the dominant contributor to the initial peaked CBFv response in all paradigms with no significant differences between paradigms, while the contribution of the stimulus explained the plateau phase and extended duration of the CBFv responses. Separating the neural activation contribution from the influences of other covariates, it was possible to detect differences between three paradigms often used to assess disease-related NVC. Apparently similar CBFv responses to different motor-cognitive paradigms can be misleading due to the contributions from peripheral covariates and could lead to inaccurate assessment of NVC, particularly during MI.

Prefrontal white matter pathology in air pollution exposed Mexico City young urbanites and their potential impact on neurovascular unit dysfunction and the development of Alzheimer's disease.

PubMed

Calderón-Garcidueñas, Lilian; Reynoso-Robles, Rafael; Vargas-Martínez, Javier; Gómez-Maqueo-Chew, Aline; Pérez-Guillé, Beatriz; Mukherjee, Partha S; Torres-Jardón, Ricardo; Perry, George; Gónzalez-Maciel, Angélica

2016-04-01

Millions of urban children are chronically exposed to high concentrations of air pollutants, i.e., fine particulate matter (PM2.5) and ozone, associated with increased risk for Alzheimer's disease. Compared with children living with clear air those in Mexico City (MC) exhibit systemic, brain and intrathecal inflammation, low CSF Aβ42, breakdown of the BBB, attention and short-term memory deficits, prefrontal white matter hyperintensities, damage to epithelial and endothelial barriers, tight junction and neural autoantibodies, and Alzheimer and Parkinson's hallmarks. The prefrontal white matter is a target of air pollution. We examined by light and electron microscopy the prefrontal white matter of MC dogs (n: 15, age 3.17±0.74 years), children and teens (n: 34, age: 12.64±4.2 years) versus controls. Major findings in MC residents included leaking capillaries and small arterioles with extravascular lipids and erythrocytes, lipofuscin in pericytes, smooth muscle and endothelial cells (EC), thickening of cerebrovascular basement membranes with small deposits of amyloid, patchy absence of the perivascular glial sheet, enlarged Virchow-Robin spaces and nanosize particles (20-48nm) in EC, basement membranes, axons and dendrites. Tight junctions, a key component of the neurovascular unit (NVU) were abnormal in MC versus control dogs (χ(2)<0.0001), and white matter perivascular damage was significantly worse in MC dogs (p=0.002). The integrity of the NVU, an interactive network of vascular, glial and neuronal cells is compromised in MC young residents. Characterizing the early NVU damage and identifying biomarkers of neurovascular dysfunction may provide a fresh insight into Alzheimer pathogenesis and open opportunities for pediatric neuroprotection. Copyright © 2015 Elsevier Inc. All rights reserved.

Advancing Cardiovascular, Neurovascular, and Renal Magnetic Resonance Imaging in Small Rodents Using Cryogenic Radiofrequency Coil Technology

PubMed Central

Niendorf, Thoralf; Pohlmann, Andreas; Reimann, Henning M.; Waiczies, Helmar; Peper, Eva; Huelnhagen, Till; Seeliger, Erdmann; Schreiber, Adrian; Kettritz, Ralph; Strobel, Klaus; Ku, Min-Chi; Waiczies, Sonia

2015-01-01

Research in pathologies of the brain, heart and kidney have gained immensely from the plethora of studies that have helped shape new methods in magnetic resonance (MR) for characterizing preclinical disease models. Methodical probing into preclinical animal models by MR is invaluable since it allows a careful interpretation and extrapolation of data derived from these models to human disease. In this review we will focus on the applications of cryogenic radiofrequency (RF) coils in small animal MR as a means of boosting image quality (e.g., by supporting MR microscopy) and making data acquisition more efficient (e.g., by reducing measuring time); both being important constituents for thorough investigational studies on animal models of disease. This review attempts to make the (bio)medical imaging, molecular medicine, and pharmaceutical communities aware of this productive ferment and its outstanding significance for anatomical and functional MR in small rodents. The goal is to inspire a more intense interdisciplinary collaboration across the fields to further advance and progress non-invasive MR methods that ultimately support thorough (patho)physiological characterization of animal disease models. In this review, current and potential future applications for the RF coil technology in cardiovascular, neurovascular, and renal disease will be discussed. PMID:26617515

Neuronal networks and mediators of cortical neurovascular coupling responses in normal and altered brain states.

PubMed

Lecrux, C; Hamel, E

2016-10-05

Brain imaging techniques that use vascular signals to map changes in neuronal activity, such as blood oxygenation level-dependent functional magnetic resonance imaging, rely on the spatial and temporal coupling between changes in neurophysiology and haemodynamics, known as 'neurovascular coupling (NVC)'. Accordingly, NVC responses, mapped by changes in brain haemodynamics, have been validated for different stimuli under physiological conditions. In the cerebral cortex, the networks of excitatory pyramidal cells and inhibitory interneurons generating the changes in neural activity and the key mediators that signal to the vascular unit have been identified for some incoming afferent pathways. The neural circuits recruited by whisker glutamatergic-, basal forebrain cholinergic- or locus coeruleus noradrenergic pathway stimulation were found to be highly specific and discriminative, particularly when comparing the two modulatory systems to the sensory response. However, it is largely unknown whether or not NVC is still reliable when brain states are altered or in disease conditions. This lack of knowledge is surprising since brain imaging is broadly used in humans and, ultimately, in conditions that deviate from baseline brain function. Using the whisker-to-barrel pathway as a model of NVC, we can interrogate the reliability of NVC under enhanced cholinergic or noradrenergic modulation of cortical circuits that alters brain states.This article is part of the themed issue 'Interpreting BOLD: a dialogue between cognitive and cellular neuroscience'. © 2016 The Author(s).

Recreating blood-brain barrier physiology and structure on chip: A novel neurovascular microfluidic bioreactor.

PubMed

Brown, Jacquelyn A; Pensabene, Virginia; Markov, Dmitry A; Allwardt, Vanessa; Neely, M Diana; Shi, Mingjian; Britt, Clayton M; Hoilett, Orlando S; Yang, Qing; Brewer, Bryson M; Samson, Philip C; McCawley, Lisa J; May, James M; Webb, Donna J; Li, Deyu; Bowman, Aaron B; Reiserer, Ronald S; Wikswo, John P

2015-09-01

The blood-brain barrier (BBB) is a critical structure that serves as the gatekeeper between the central nervous system and the rest of the body. It is the responsibility of the BBB to facilitate the entry of required nutrients into the brain and to exclude potentially harmful compounds; however, this complex structure has remained difficult to model faithfully in vitro. Accurate in vitro models are necessary for understanding how the BBB forms and functions, as well as for evaluating drug and toxin penetration across the barrier. Many previous models have failed to support all the cell types involved in the BBB formation and/or lacked the flow-created shear forces needed for mature tight junction formation. To address these issues and to help establish a more faithful in vitro model of the BBB, we have designed and fabricated a microfluidic device that is comprised of both a vascular chamber and a brain chamber separated by a porous membrane. This design allows for cell-to-cell communication between endothelial cells, astrocytes, and pericytes and independent perfusion of both compartments separated by the membrane. This NeuroVascular Unit (NVU) represents approximately one-millionth of the human brain, and hence, has sufficient cell mass to support a breadth of analytical measurements. The NVU has been validated with both fluorescein isothiocyanate (FITC)-dextran diffusion and transendothelial electrical resistance. The NVU has enabled in vitro modeling of the BBB using all human cell types and sampling effluent from both sides of the barrier.

Memantine mediates neuroprotection via regulating neurovascular unit in a mouse model of focal cerebral ischemia.

PubMed

Chen, Zheng-Zhen; Yang, Dan-Dan; Zhao, Zhan; Yan, Hui; Ji, Juan; Sun, Xiu-Lan

2016-04-01

Memantine is a low-moderate affinity and uncompetitive N-methyl-d-aspartate receptor (NMDAR) antagonist, which is also a potential neuroprotectant in acute ischemic stroke for its particular action profiles. The present study was to reveal the mechanisms involved in the neuroprotection of memantine. We used a mouse model of permanent focal cerebral ischemia via middle cerebral artery occlusion to verify our hypothesis. 2,3,5-Triphenyltetrazolium chloride staining was used to compare infarct size. The amount of astrocytes and the somal volume of the microglia cell body were analyzed by immunohistochemistry and stereological estimates. Western blotting was used to determine the protein expressions. Memantine prevented cerebral ischemia-induced brain infarct and neuronal injury, and reduced oxygen-glucose deprivation-induced cortical neuronal apoptosis. Moreover, memantine reduced the amount of the damaged astrocytes and over activated microglia after 24h of ischemia. In the early phase of ischemia, higher production of MMP-9 was observed, and thereby collagen IV was dramatically disrupted. Meanwhile, the post-synaptic density protein 95(PSD-95) was also severely cleavaged. Memantine decreased MMP-9 secretion, prevented the degradation of collagen IV in mouse brain. PSD-95 cleavage was also inhibited by memantine. These results suggested that memantine exerted neuroprotection effects in acute ischemic brain damage, partially via improving the functions of neurovascular unit. Taking all these findings together, we consider that memantine might be a promising protective agent against ischemic stroke. Copyright © 2016 Elsevier Inc. All rights reserved.

Cholesterol as a modifying agent of the neurovascular unit structure and function under physiological and pathological conditions.

PubMed

Czuba, Ewelina; Steliga, Aleksandra; Lietzau, Grażyna; Kowiański, Przemysław

2017-08-01

The brain, demanding constant level of cholesterol, precisely controls its synthesis and homeostasis. The brain cholesterol pool is almost completely separated from the rest of the body by the functional blood-brain barrier (BBB). Only a part of cholesterol pool can be exchanged with the blood circulation in the form of the oxysterol metabolites such, as 27-hydroxycholesterol (27-OHC) and 24S-hydroxycholesterol (24S-OHC). Not only neurons but also blood vessels and neuroglia, constituting neurovascular unit (NVU), are crucial for the brain cholesterol metabolism and undergo precise regulation by numerous modulators, metabolites and signal molecules. In physiological conditions maintaining the optimal cholesterol concentration is important for the energetic metabolism, composition of cell membranes and myelination. However, a growing body of evidence indicates the consequences of the cholesterol homeostasis dysregulation in several pathophysiological processes. There is a causal relationship between hypercholesterolemia and 1) development of type 2 diabetes due to long-term high-fat diet consumption, 2) significance of the oxidative stress consequences for cerebral amyloid angiopathy and neurodegenerative diseases, 3) insulin resistance on progression of the neurodegenerative brain diseases. In this review, we summarize the current state of knowledge concerning the cholesterol influence upon functioning of the NVU under physiological and pathological conditions.

Dissociation of metabolic and neurovascular responses to levodopa in the treatment of Parkinson's disease.

PubMed

Hirano, Shigeki; Asanuma, Kotaro; Ma, Yilong; Tang, Chengke; Feigin, Andrew; Dhawan, Vijay; Carbon, Maren; Eidelberg, David

2008-04-16

We compared the metabolic and neurovascular effects of levodopa (LD) therapy for Parkinson's disease (PD). Eleven PD patients were scanned with both [15O]-H2O and [18F]-fluorodeoxyglucose positron emission tomography in the unmedicated state and during intravenous LD infusion. Images were used to quantify LD-mediated changes in the expression of motor- and cognition-related PD covariance patterns in scans of cerebral blood flow (CBF) and cerebral metabolic rate for glucose (CMR). These changes in network activity were compared with those occurring during subthalamic nucleus (STN) deep brain stimulation (DBS), and those observed in a test-retest PD control group. Separate voxel-based searches were conducted to identify individual regions with dissociated treatment-mediated changes in local cerebral blood flow and metabolism. We found a significant dissociation between CBF and CMR in the modulation of the PD motor-related network by LD treatment (p < 0.001). This dissociation was characterized by reductions in network activity in the CMR scans (p < 0.003) occurring concurrently with increases in the CBF scans (p < 0.01). Flow-metabolism dissociation was also evident at the regional level, with LD-mediated reductions in CMR and increases in CBF in the putamen/globus pallidus, dorsal midbrain/pons, STN, and ventral thalamus. CBF responses to LD in the putamen and pons were relatively greater in patients exhibiting drug-induced dyskinesia. In contrast, flow-metabolism dissociation was not present in the STN DBS treatment group or in the PD control group. These findings suggest that flow-metabolism dissociation is a distinctive feature of LD treatment. This phenomenon may be especially pronounced in patients with LD-induced dyskinesia.

[Medical movement in Mexico. To 50 years. Open file].

PubMed

Sandoval-Gutiérrez, José Luis

2017-01-01

Gutiérrez-Samperio hace una excelente narrativa del movimiento denominado «blanco» hace medio siglo, encabezado por médicos y otros trabajadores de salud, principalmente enfermeras. Es importante revisar los logros y limitaciones que dicho fenómeno alcanzó. Por ejemplo, actualmente el residente que cursa una especialidad cuenta con un reconocimiento institucional, universitario y de profesiones al término de su formación, además de tener una beca económica (probablemente insuficiente) y días de vacaciones programados.

Neurovascular Network Explorer 1.0: a database of 2-photon single-vessel diameter measurements with MATLAB(®) graphical user interface.

PubMed

Sridhar, Vishnu B; Tian, Peifang; Dale, Anders M; Devor, Anna; Saisan, Payam A

2014-01-01

We present a database client software-Neurovascular Network Explorer 1.0 (NNE 1.0)-that uses MATLAB(®) based Graphical User Interface (GUI) for interaction with a database of 2-photon single-vessel diameter measurements from our previous publication (Tian et al., 2010). These data are of particular interest for modeling the hemodynamic response. NNE 1.0 is downloaded by the user and then runs either as a MATLAB script or as a standalone program on a Windows platform. The GUI allows browsing the database according to parameters specified by the user, simple manipulation and visualization of the retrieved records (such as averaging and peak-normalization), and export of the results. Further, we provide NNE 1.0 source code. With this source code, the user can database their own experimental results, given the appropriate data structure and naming conventions, and thus share their data in a user-friendly format with other investigators. NNE 1.0 provides an example of seamless and low-cost solution for sharing of experimental data by a regular size neuroscience laboratory and may serve as a general template, facilitating dissemination of biological results and accelerating data-driven modeling approaches.

Blood–Brain Barrier Leakage during Early Epileptogenesis Is Associated with Rapid Remodeling of the Neurovascular Unit

PubMed Central

Breuer, Heike; Leiter, Ina; Märkel, Martin; Bascuñana, Pablo; Michalski, Dominik; Bengel, Frank M.; Löscher, Wolfgang; Meier, Martin; Bankstahl, Jens P.; Härtig, Wolfgang

2018-01-01

Abstract Increased permeability of the blood–brain barrier (BBB) following cerebral injury results in regional extravasation of plasma proteins and can critically contribute to the pathogenesis of epilepsy. Here, we comprehensively explore the spatiotemporal evolution of a main extravasation component, albumin, and illuminate associated responses of the neurovascular unit (NVU) contributing to early epileptogenic neuropathology. We applied translational in vivo MR imaging and complementary immunohistochemical analyses in the widely used rat pilocarpine post–status epilepticus (SE) model. The observed rapid BBB leakage affected major epileptogenesis-associated brain regions, peaked between 1 and 2 d post-SE, and rapidly declined thereafter, accompanied by cerebral edema generally following the same time course. At peak of BBB leakage, serum albumin colocalized with NVU constituents, such as vascular components, neurons, and brain immune cells. Surprisingly, astroglial markers did not colocalize with albumin, and aquaporin-4 (AQP4) was clearly reduced in areas of leaky BBB, indicating a severe disturbance of astrocyte-mediated endothelial-neuronal coupling. In addition, a distinct adaptive reorganization process of the NVU vasculature apparently takes place at sites of albumin presence, substantiated by reduced immunoreactivity of endothelial and changes in vascular basement membrane markers. Taken together, degenerative events at the level of the NVU, affecting vessels, astrocytes, and neurons, seem to outweigh reconstructive processes. Considering the rapidly occurring BBB leakage and subsequent impairment of the NVU, our data support the necessity of a prompt BBB-restoring treatment as one component of rational therapeutic intervention to prevent epileptogenesis and the development of other detrimental sequelae of SE. PMID:29854942

Baroreflex and neurovascular responses to skeletal muscle mechanoreflex activation in humans: an exercise in integrative physiology.

PubMed

Drew, Rachel C

2017-12-01

Cardiovascular adjustments to exercise resulting in increased blood pressure (BP) and heart rate (HR) occur in response to activation of several neural mechanisms: the exercise pressor reflex, central command, and the arterial baroreflex. Neural inputs from these feedback and feedforward mechanisms integrate in the cardiovascular control centers in the brain stem and modulate sympathetic and parasympathetic neural outflow, resulting in the increased BP and HR observed during exercise. Another specific consequence of the central neural integration of these inputs during exercise is increased sympathetic neural outflow directed to the kidneys, causing renal vasoconstriction, a key reflex mechanism involved in blood flow redistribution during increased skeletal muscle work. Studies in humans have shown that muscle mechanoreflex activation inhibits cardiac vagal outflow, decreasing the sensitivity of baroreflex control of HR. Metabolite sensitization of muscle mechanoreceptors can lead to reduced sensitivity of baroreflex control of HR, with thromboxane being one of the metabolites involved, via greater inhibition of cardiac vagal outflow without affecting baroreflex control of BP or baroreflex resetting. Muscle mechanoreflex activation appears to play a predominant role in causing renal vasoconstriction, both in isolation and in the presence of local metabolites. Limited investigations in older adults and patients with cardiovascular-related disease have provided some insight into how the influence of muscle mechanoreflex activation on baroreflex function and renal vasoconstriction is altered in these populations. However, future research is warranted to better elucidate the specific effect of muscle mechanoreflex activation on baroreflex and neurovascular responses with aging and cardiovascular-related disease. Copyright © 2017 the American Physiological Society.

Presurgical visualization of the neurovascular relationship in trigeminal neuralgia with 3D modeling using free Slicer software.

PubMed

Han, Kai-Wei; Zhang, Dan-Feng; Chen, Ji-Gang; Hou, Li-Jun

2016-11-01

To explore whether segmentation and 3D modeling are more accurate in the preoperative detection of the neurovascular relationship (NVR) in patients with trigeminal neuralgia (TN) compared to MRI fast imaging employing steady-state acquisition (FIESTA). Segmentation and 3D modeling using 3D Slicer were conducted for 40 patients undergoing MRI FIESTA and microsurgical vascular decompression (MVD). The NVR, as well as the offending vessel determined by MRI FIESTA and 3D Slicer, was reviewed and compared with intraoperative manifestations using SPSS. The k agreement between the MRI FIESTA and operation in determining the NVR was 0.232 and that between the 3D modeling and operation was 0.6333. There was no significant difference between these two procedures (χ 2  = 8.09, P = 0.088). The k agreement between the MRI FIESTA and operation in determining the offending vessel was 0.373, and that between the 3D modeling and operation was 0.922. There were significant differences between two of them (χ 2  = 82.01, P = 0.000). The sensitivity and specificity for MRI FIESTA in determining the NVR were 87.2 % and 100 %, respectively, and for 3D modeling were both 100 %. The segmentation and 3D modeling were more accurate than MRI FIESTA in preoperative verification of the NVR and offending vessel. This was consistent with surgical manifestations and was more helpful for the preoperative decision and surgical plan.

The neurovascular complexity index as a potential indicator of traumatic brain injury severity: A case-series study.

PubMed

Howard, Jeffrey T; Janak, Jud C; Bukhman, Vladislav; Robertson, Claudia; Frolov, Iurii; Nawn, Corinne D; Schiller, Alicia M; Convertino, Victor A

2017-07-01

Multimodal monitoring of brain physiology following a traumatic brain injury (TBI) shows promise as a strategy to improve management and outcomes of TBI patients within civilian and military trauma. Valid and reliable measures of different aspects of brain physiology following a TBI could prove critical to accurately capturing these changes. Using a case-series design with a control subject group comparison, we evaluated a new proprietary algorithm called the Neurovascular Complexity Index (NCI) using transcranial Doppler to noninvasively obtain measures of cerebral blood flow variability. Baseline NCI data from 169 control subjects were compared with 12 patients with moderate to severe TBI. Patients with TBI exhibited significantly greater mean and variability in NCI scores compared with control subjects (F = 195.48; p < 0.001). The mean absolute deviation (MAD) of NCI scores increased significantly and in a monotonic fashion with severity of injury, where control subjects exhibited a small MAD of 0.44, patients with moderate TBI had a higher MAD of 4.20, and patients with severe TBI had an MAD of 6.51 (p < 0.001). Advancement in multimodal monitoring of TBI patients is important in reducing the potential risk of secondary injury. This study reports results indicating that a new noninvasive quantifiable assessment of TBI based on a noninvasive measure of cerebral blood flow variability shows potential for continuous monitoring and early identification of brain-injured patients, deployable in far-forward military environments, to better inform individualized management. Case series, level IV.

The Pros and Cons of Army Automation

DTIC Science & Technology

2007-11-13

The Pros and Cons of Army Automation 1 Running Head: THE PROS AND CONS OF ARMY AUTOMATION The Pros and Cons of Army Automation SGM...TITLE AND SUBTITLE The Pros and Cons of Army Automation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...Prescribed by ANSI Std Z39-18 The Pros and Cons of Army Automation 2 Outline I. Introduction (MSG (P) Dostie) II. Manual skills (MSG (P

Experimental and Computational Studies of Carbonyl Diazide (CON6) as a Precursor to Diazirinone (CON2)

NASA Astrophysics Data System (ADS)

Esselman, Brian J.; Amberger, Brent K.; Nolan, Alex M.; Woods, R. Claude; McMahon, R. J.

2011-10-01

Intrigued by the reported 2005 synthesis of diazirinone (1), we carried out further experimental and theoretical studies aimed at the detailed matrix-isolation and millimeter-wave spectroscopic characterizations of 1. Diazirinone (1) is a peculiar isoconjugate of two very stable molecules and may be of astrochemical interest. Unfortunately, the original reported methods of diazirinone (1) generation did not yield this species, rather its decomposition products. Inspired by a more recent gas phase pyrolysis of CON6 (2) to yield CON2 (1), we proposed a new method of generating CON6 (2) in solution as a precursor of diazirinone (1). This new synthesis may allow us to generate larger quantities of both CON6 and CON2 for investigation by millimeter-wave spectroscopy. We are able to safely generate carbonyl diazide (2) in sufficient yield from the reaction of triphosgene (3) and tetrabutylammonium azide in diethyl ether. This has allowed us to obtain both matrix-isolation and gas phase IR spectra of carbonyl diazide (2). After purification, it has a gas-phase lifetime that allows samples to be useable for up to several weeks. However, it is a shock-sensitive material that must be handled with care to prevent violent decomposition. In order to provide better mechanistic insight into the decomposition of carbonyl diazide (2) to diazirinone (1), we have engaged in a DFT and ab initio computational study. We have found a pathway between the two species via the triplet acylnitrene, CON4, and an oxaziridine CON2 species, but not at sufficiently low energies to allow for the trapping and detection of diazirinone (1). Preliminary millimeter-wave spectra have been obtained from several synthesized and purified samples of CON6 (2). However, the assignment of the spectra lines has been unexpectedly problematic. We have placed several CON6 (2) samples, confirmed by IR spectroscopy at the time of sample loading, into our instrument and obtained two different sets of rotational lines

Neurovascular bundle–sparing radiotherapy for prostate cancer using MRI-CT registration: A dosimetric feasibility study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cassidy, R.J., E-mail: richardjcassidy@emory.edu; Yang, X.; Liu, T.

Purpose: Sexual dysfunction after radiotherapy for prostate cancer remains an important late adverse toxicity. The neurovascular bundles (NVB) that lie posterolaterally to the prostate are typically spared during prostatectomy, but in traditional radiotherapy planning they are not contoured as an organ-at-risk with dose constraints. Our goal was to determine the dosimetric feasibility of “NVB-sparing” prostate radiotherapy while still delivering adequate dose to the prostate. Methods: Twenty-five consecutive patients with prostate cancer (with no extraprostatic disease on pelvic magnetic resonance imaging [MRI]) who that were treated with external beam radiotherapy, with the same primary planning target volume margins, to a dosemore » of 79.2 Gy were evaluated. Pelvic MRI and simulation computed tomography scans were registered using dedicated software to allow for bilateral NVB target delineation on T2-weighted MRI. A volumetric modulated arc therapy plan was generated using the NVB bilaterally with 2 mm margin as an organ to spare and compared to the patient’s previously delivered plan. Dose-volume histogram endpoints for NVB, rectum, bladder, and planning target volume 79.2 were compared between the 2 plans using a 2-tailed paired t-test. Results: The V70 for the NVB was significantly lower on the NVB-sparing plan (p <0.01), while rectum and bladder endpoints were similar. Target V100% was similar but V{sub 105%} was higher for the NVB-sparing plans (p <0.01). Conclusions: “NVB-sparing” radiotherapy is dosimetrically feasible using CT-MRI registration, and for volumetric modulated arc therapy technology — target coverage is acceptable without increased dose to other normal structures, but with higher target dose inhomogeneity. The clinical impact of “NVB-sparing” radiotherapy is currently under study at our institution.« less

Rescue of cortical neurovascular functions during the hyperacute phase of ischemia by peripheral sensory stimulation.

PubMed

Liao, Lun-De; Liu, Yu-Hang; Lai, Hsin-Yi; Bandla, Aishwarya; Shih, Yen-Yu Ian; Chen, You-Yin; Thakor, Nitish V

2015-03-01

To investigate the potential therapeutic effects of peripheral sensory stimulation during the hyperacute phase of stroke, the present study utilized electrophysiology and photoacoustic imaging techniques to evaluate neural and vascular responses of the rat cortex following ischemic insult. We employed a rat model of photothrombotic ischemia (PTI), which targeted the forelimb region of the primary somatosensory cortex (S1FL), due to its high reproducibility in creating localized ischemic injury. We also established a hybrid, dual-modality system, including six-channel electrocorticography (ECoG) and functional photoacoustic microscopy (fPAM), termed ECoG-fPAM, to image brain functional responses to peripheral sensory stimulation during the hyperacute phase of PTI. Our results showed that the evoked cerebral blood volume (CBV) and hemoglobin oxygen saturation (SO2) recovered to 84±7.4% and 79±6.2% of the baseline, respectively, when stimulation was delivered within 2.5 h following PTI induction. Moreover, neural activity significantly recovered, with 77±8.6%, 76±5.3% and 89±8.2% recovery for the resting-state inter-hemispheric coherence, alpha-to-delta ratio (ADR) and somatosensory evoked potential (SSEP), respectively. Additionally, we integrated the CBV or SO2 with ADR values as a recovery indicator (RI) to assess functional recovery after PTI. The RI indicated that 80±4.2% of neurovascular function was preserved when stimulation was delivered within 2.5h. Additionally, stimulation treatment within this optimal time window resulted in a minimal infarct volume in the ischemic hemisphere (4.6±2.1%). In contrast, the infarct volume comprised 13.7±1.7% of the ischemic hemisphere when no stimulation treatment was applied. Copyright © 2014. Published by Elsevier Inc.

Whole-Mount Adult Ear Skin Imaging Reveals Defective Neuro-Vascular Branching Morphogenesis in Obese and Type 2 Diabetic Mouse Models.

PubMed

Yamazaki, Tomoko; Li, Wenling; Yang, Ling; Li, Ping; Cao, Haiming; Motegi, Sei-Ichiro; Udey, Mark C; Bernhard, Elise; Nakamura, Takahisa; Mukouyama, Yoh-Suke

2018-01-11

Obesity and type 2 diabetes are frequently associated with peripheral neuropathy. Though there are multiple methods for diagnosis and analysis of morphological changes of peripheral nerves and blood vessels, three-dimensional high-resolution imaging is necessary to appreciate the pathogenesis with an anatomically recognizable branching morphogenesis and patterning. Here we established a novel technique for whole-mount imaging of adult mouse ear skin to visualize branching morphogenesis and patterning of peripheral nerves and blood vessels. Whole-mount immunostaining of adult mouse ear skin showed that peripheral sensory and sympathetic nerves align with large-diameter blood vessels. Diet-induced obesity (DIO) mice exhibit defective vascular smooth muscle cells (VSMCs) coverage, while there is no significant change in the amount of peripheral nerves. The leptin receptor-deficient db/db mice, a severe obese and type 2 diabetic mouse model, exhibit defective VSMC coverage and a large increase in the amount of smaller-diameter nerve bundles with myelin sheath and unmyelinated nerve fibers. Interestingly, an increase in the amount of myeloid immune cells was observed in the DIO but not db/db mouse skin. These data suggest that our whole-mount imaging method enables us to investigate the neuro-vascular and neuro-immune phenotypes in the animal models of obesity and diabetes.

Endovascular Treatment of Wide-Necked Visceral Artery Aneurysms Using the Neurovascular Comaneci Neck-Bridging Device: A Technical Report.

PubMed

Maingard, Julian; Kok, Hong Kuan; Phelan, Emma; Logan, Caitriona; Ranatunga, Dinesh; Brooks, Duncan Mark; Chandra, Ronil V; Lee, Michael J; Asadi, Hamed

2017-11-01

Visceral and renal artery aneurysms (VRAAs) are an uncommon clinical entity but carry a risk of rupture with associated morbidity and mortality. The rupture risk is particularly high when the aneurysms are large, of unfavourable morphology or in the setting of pregnancy and perioperative period. Endovascular approaches are now first line in the treatment of VRAA, but conventional techniques may be ineffective in excluding aneurysms with unfavourable anatomy such as those with wide necks or at arterial bifurcation points. The neurovascular Comaneci neck-bridging device is used to temporarily cover the neck of intracranial aneurysms without occluding forward arterial flow during endovascular coiling. We report the novel use of the Comaneci neck-bridging device for the treatment of complex peripheral VRAAs. We describe the treatment of two patients with renal and splenic artery aneurysms demonstrating unfavourable anatomic morphology for conventional endovascular approaches. In the first patient, the renal artery aneurysm was situated at the intrarenal bifurcation of the main renal artery in the setting of a solitary kidney. In the second patient, the splenic artery aneurysm was situated close to the splenic hilum at the distal splenic arterial bifurcation. The Comaneci neck-bridging device was successfully used in both cases to assist coil embolisation with visceral preservation. The Comaneci neck-bridging device is potentially safe and effective for the treatment of peripheral VRAA with unfavourable anatomic characteristics that would have been deemed unsuitable for treatment using conventional techniques. Level 4, Technical Report.

Predictive value of magnetic resonance for identifying neurovascular compressions in trigeminal neuralgia.

PubMed

Ruiz-Juretschke, F; Guzmán-de-Villoria, J G; García-Leal, R; Sañudo, J R

2017-05-23

Microvascular decompression (MVD) is accepted as the only aetiological surgical treatment for refractory classic trigeminal neuralgia (TN). There is therefore increasing interest in establishing the diagnostic and prognostic value of identifying neurovascular compressions (NVC) using preoperative high-resolution three-dimensional magnetic resonance (MRI) in patients with classic TN who are candidates for surgery. This observational study includes a series of 74 consecutive patients with classic TN treated with MVD. All patients underwent a preoperative three-dimensional high-resolution MRI with DRIVE sequences to diagnose presence of NVC, as well as the degree, cause, and location of compressions. MRI results were analysed by doctors blinded to surgical findings and subsequently compared to those findings. After a minimum follow-up time of six months, we assessed the surgical outcome and graded it on the Barrow Neurological Institute pain intensity score (BNI score). The prognostic value of the preoperative MRI was estimated using binary logistic regression. Preoperative DRIVE MRI sequences showed a sensitivity of 95% and a specificity of 87%, with a 98% positive predictive value and a 70% negative predictive value. Moreover, Cohen's kappa (CK) indicated a good level of agreement between radiological and surgical findings regarding presence of NVC (CK 0.75), type of compression (CK 0.74) and the site of compression (CK 0.72), with only moderate agreement as to the degree of compression (CK 0.48). After a mean follow-up of 29 months (range 6-100 months), 81% of the patients reported pain control with or without medication (BNI score i-iiiI). Patients with an excellent surgical outcome, i.e. without pain and off medication (BNI score i), made up 66% of the total at the end of follow-up. Univariate analysis using binary logistic regression showed that a diagnosis of NVC on the preoperative MRI was a favorable prognostic factor that significantly increased the odds of

9 CFR 319.300 - Chili con carne.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Chili con carne. 319.300 Section 319.300 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... Products § 319.300 Chili con carne. “Chili con carne” shall contain not less than 40 percent of meat...

Design of catheter radio frequency coils using coaxial transmission line resonators for interventional neurovascular MR imaging.

PubMed

Zhang, Xiaoliang; Martin, Alastair; Jordan, Caroline; Lillaney, Prasheel; Losey, Aaron; Pang, Yong; Hu, Jeffrey; Wilson, Mark; Cooke, Daniel; Hetts, Steven W

2017-04-01

It is technically challenging to design compact yet sensitive miniature catheter radio frequency (RF) coils for endovascular interventional MR imaging. In this work, a new design method for catheter RF coils is proposed based on the coaxial transmission line resonator (TLR) technique. Due to its distributed circuit, the TLR catheter coil does not need any lumped capacitors to support its resonance, which simplifies the practical design and construction and provides a straightforward technique for designing miniature catheter-mounted imaging coils that are appropriate for interventional neurovascular procedures. The outer conductor of the TLR serves as an RF shield, which prevents electromagnetic energy loss, and improves coil Q factors. It also minimizes interaction with surrounding tissues and signal losses along the catheter coil. To investigate the technique, a prototype catheter coil was built using the proposed coaxial TLR technique and evaluated with standard RF testing and measurement methods and MR imaging experiments. Numerical simulation was carried out to assess the RF electromagnetic field behavior of the proposed TLR catheter coil and the conventional lumped-element catheter coil. The proposed TLR catheter coil was successfully tuned to 64 MHz for proton imaging at 1.5 T. B 1 fields were numerically calculated, showing improved magnetic field intensity of the TLR catheter coil over the conventional lumped-element catheter coil. MR images were acquired from a dedicated vascular phantom using the TLR catheter coil and also the system body coil. The TLR catheter coil is able to provide a significant signal-to-noise ratio (SNR) increase (a factor of 200 to 300) over its imaging volume relative to the body coil. Catheter imaging RF coil design using the proposed coaxial TLR technique is feasible and advantageous in endovascular interventional MR imaging applications.

Mincle Signaling Promotes Con-A Hepatitis

PubMed Central

Greco, Stephanie H.; Torres-Hernandez, Alejandro; Kalabin, Aleksandr; Whiteman, Clint; Rokosh, Rae; Ravirala, Sushma; Ochi, Atsuo; Gutierrez, Johana; Salyana, Muhammad Atif; Mani, Vishnu R.; Nagaraj, Savitha V.; Deutsch, Michael; Seifert, Lena; Daley, Donnele; Barilla, Rocky; Hundeyin, Mautin; Nikifrov, Yuriy; Tejada, Karla; Gelb, Bruce E.; Katz, Steven C.; Miller, George

2016-01-01

Concanavalin-A (Con-A) hepatitis is regarded as a T cell-mediated model of acute liver injury. Mincle is a C-type lectin receptor (CLR) that is critical in the immune response to mycobacteria and fungi, but does not have a well-defined role in pre-clinical models of non-pathogen mediated inflammation. Since Mincle can ligate the cell death ligand SAP130, we postulated that Mincle signaling drives intrahepatic inflammation and liver injury in Con-A hepatitis. Acute liver injury was assessed in the murine Con-A hepatitis model using C57BL/6, Mincle−/−, and Dectin-1−/− mice. The role of C/EBPβ and HIF-1α signaling was assessed using selective inhibitors. We found that Mincle was highly expressed in hepatic innate inflammatory cells and endothelial cells in both mice and humans. Furthermore, sterile Mincle ligands and Mincle signaling intermediates were increased in the murine liver in Con-A hepatitis. Most significantly, Mincle deletion or blockade protected against Con-A hepatitis whereas Mincle ligation exacerbated disease. Bone marrow chimeric and adoptive transfer experiments suggested that Mincle signaling in infiltrating myeloid cells dictates disease phenotype. Conversely, signaling via other CLRs did not alter disease course. Mechanistically, we found that Mincle blockade decreased the NF-κβ related signaling intermediates, C/EBPβ and HIF-1α, both of which are necessary in macrophage-mediated inflammatory responses. Accordingly, Mincle deletion lowered production of nitrites in Con-A hepatitis and inhibition of both C/EBPβ and HIF1-α reduced the severity of liver disease. Our work implicates a novel innate immune driver of Con-A hepatitis and, more broadly, suggests a potential role for Mincle in diseases governed by sterile inflammation. PMID:27559045

Mincle Signaling Promotes Con A Hepatitis.

PubMed

Greco, Stephanie H; Torres-Hernandez, Alejandro; Kalabin, Aleksandr; Whiteman, Clint; Rokosh, Rae; Ravirala, Sushma; Ochi, Atsuo; Gutierrez, Johana; Salyana, Muhammad Atif; Mani, Vishnu R; Nagaraj, Savitha V; Deutsch, Michael; Seifert, Lena; Daley, Donnele; Barilla, Rocky; Hundeyin, Mautin; Nikifrov, Yuriy; Tejada, Karla; Gelb, Bruce E; Katz, Steven C; Miller, George

2016-10-01

Con A hepatitis is regarded as a T cell-mediated model of acute liver injury. Mincle is a C-type lectin receptor that is critical in the immune response to mycobacteria and fungi but does not have a well-defined role in preclinical models of non-pathogen-mediated inflammation. Because Mincle can ligate the cell death ligand SAP130, we postulated that Mincle signaling drives intrahepatic inflammation and liver injury in Con A hepatitis. Acute liver injury was assessed in the murine Con A hepatitis model using C57BL/6, Mincle(-/-), and Dectin-1(-/-) mice. The role of C/EBPβ and hypoxia-inducible factor-1α (HIF-1α) signaling was assessed using selective inhibitors. We found that Mincle was highly expressed in hepatic innate inflammatory cells and endothelial cells in both mice and humans. Furthermore, sterile Mincle ligands and Mincle signaling intermediates were increased in the murine liver in Con A hepatitis. Most significantly, Mincle deletion or blockade protected against Con A hepatitis, whereas Mincle ligation exacerbated disease. Bone marrow chimeric and adoptive transfer experiments suggested that Mincle signaling in infiltrating myeloid cells dictates disease phenotype. Conversely, signaling via other C-type lectin receptors did not alter disease course. Mechanistically, we found that Mincle blockade decreased the NF-κβ-related signaling intermediates C/EBPβ and HIF-1α, both of which are necessary in macrophage-mediated inflammatory responses. Accordingly, Mincle deletion lowered production of nitrites in Con A hepatitis and inhibition of both C/EBPβ and HIF-1α reduced the severity of liver disease. Our work implicates a novel innate immune driver of Con A hepatitis and, more broadly, suggests a potential role for Mincle in diseases governed by sterile inflammation. Copyright © 2016 by The American Association of Immunologists, Inc.

The potential complications of open carpal tunnel release surgery to the ulnar neurovascular bundle and its branches: A cadaveric study.

PubMed

Boughton, O; Adds, P J; Jayasinghe, J A P

2010-07-01

This study investigated the ulnar artery and the ulnar nerve and its branches in the palm to assess how frequently they may be at risk of damage during open carpal tunnel release surgery. Twenty-one formalin-embalmed cadaveric hands were dissected, and the proximity of the ulnar neurovascular bundle to two different lines of incision, the 3rd and 4th interdigital web space axis and the ring finger axis, was assessed and compared. It was found that an incision in the latter (ring finger) axis put the ulnar artery at risk in 12 of 21 specimens, whereas an incision in the former axis (3rd/4th interdigital web space) put the ulnar artery at risk in only two specimens. In 15 hands at least one structure (the ulnar artery or a branch of the ulnar nerve) was at risk in the ring finger axis compared to only seven hands in the axis of the 3rd/4th interdigital web space. We conclude that the ulnar artery and branches of the ulnar nerve are at increased risk of damage with an incision in the axis of the ring finger. The importance of using a blunt dissection technique under direct vision during surgery to identify and preserve these structures and median nerve branches is emphasized. (c) 2010 Wiley-Liss, Inc.

Functional Polarity of Microvascular Brain Endothelial Cells Supported by Neurovascular Unit Computational Model of Large Neutral Amino Acid Homeostasis

PubMed Central

Taslimifar, Mehdi; Buoso, Stefano; Verrey, Francois; Kurtcuoglu, Vartan

2018-01-01

The homeostatic regulation of large neutral amino acid (LNAA) concentration in the brain interstitial fluid (ISF) is essential for proper brain function. LNAA passage into the brain is primarily mediated by the complex and dynamic interactions between various solute carrier (SLC) transporters expressed in the neurovascular unit (NVU), among which SLC7A5/LAT1 is considered to be the major contributor in microvascular brain endothelial cells (MBEC). The LAT1-mediated trans-endothelial transport of LNAAs, however, could not be characterized precisely by available in vitro and in vivo standard methods so far. To circumvent these limitations, we have incorporated published in vivo data of rat brain into a robust computational model of NVU-LNAA homeostasis, allowing us to evaluate hypotheses concerning LAT1-mediated trans-endothelial transport of LNAAs across the blood brain barrier (BBB). We show that accounting for functional polarity of MBECs with either asymmetric LAT1 distribution between membranes and/or intrinsic LAT1 asymmetry with low intraendothelial binding affinity is required to reproduce the experimentally measured brain ISF response to intraperitoneal (IP) L-tyrosine and L-phenylalanine injection. On the basis of these findings, we have also investigated the effect of IP administrated L-tyrosine and L-phenylalanine on the dynamics of LNAAs in MBECs, astrocytes and neurons. Finally, the computational model was shown to explain the trans-stimulation of LNAA uptake across the BBB observed upon ISF perfusion with a competitive LAT1 inhibitor. PMID:29593549

Women in Combat Pros and Cons

DTIC Science & Technology

1988-04-01

and Cons . Major Thomas H. Cecil 88-0490 "--"insights into tomorrou,"’ ..v- A A 0 PtY-i f(.> i’I,-:::x:’~ --pcr~ j.~ ~~* --. -- iiV • DISCLAIMER The...k. r- r,’ I’. REPORT NUMBER 88-0490 TITLE WOMEN IN COMBAT-PROS AND CONS AUTHOR(S) MAJOR THOMAS H. CEC-IL, USAF -% FACULTY ADVISOR CH, LT COL DAVID W...NUMBERS 11 TITLE (include Security Classification) WOMEN IN COMBAT--PROS AND CONS 12. PERSON4AL AUTHOR(S) Cecil, Thomas H1., Major, USAF 9a YýOF REPORT

Functional vascular contributions to cognitive impairment and dementia: mechanisms and consequences of cerebral autoregulatory dysfunction, endothelial impairment, and neurovascular uncoupling in aging

PubMed Central

Toth, Peter; Tarantini, Stefano; Csiszar, Anna

2017-01-01

Increasing evidence from epidemiological, clinical and experimental studies indicate that age-related cerebromicrovascular dysfunction and microcirculatory damage play critical roles in the pathogenesis of many types of dementia in the elderly, including Alzheimer’s disease. Understanding and targeting the age-related pathophysiological mechanisms that underlie vascular contributions to cognitive impairment and dementia (VCID) are expected to have a major role in preserving brain health in older individuals. Maintenance of cerebral perfusion, protecting the microcirculation from high pressure-induced damage and moment-to-moment adjustment of regional oxygen and nutrient supply to changes in demand are prerequisites for the prevention of cerebral ischemia and neuronal dysfunction. This overview discusses age-related alterations in three main regulatory paradigms involved in the regulation of cerebral blood flow (CBF): cerebral autoregulation/myogenic constriction, endothelium-dependent vasomotor function, and neurovascular coupling responses responsible for functional hyperemia. The pathophysiological consequences of cerebral microvascular dysregulation in aging are explored, including blood-brain barrier disruption, neuroinflammation, exacerbation of neurodegeneration, development of cerebral microhemorrhages, microvascular rarefaction, and ischemic neuronal dysfunction and damage. Due to the widespread attention that VCID has captured in recent years, the evidence for the causal role of cerebral microvascular dysregulation in cognitive decline is critically examined. PMID:27793855

Delayed histochemical alterations within the neurovascular unit due to transient focal cerebral ischemia and experimental treatment with neurotrophic factors.

PubMed

Michalski, Dominik; Pitsch, Roman; Pillai, Deepu R; Mages, Bianca; Aleithe, Susanne; Grosche, Jens; Martens, Henrik; Schlachetzki, Felix; Härtig, Wolfgang

2017-01-01

Current stroke therapy is focused on recanalizing strategies, but neuroprotective co-treatments are still lacking. Modern concepts of the ischemia-affected neurovascular unit (NVU) and surrounding penumbra emphasize the complexity during the transition from initial damaging to regenerative processes. While early treatment with neurotrophic factors was shown to result in lesion size reduction and blood-brain barrier (BBB) stabilization, cellular consequences from these treatments are poorly understood. This study explored delayed cellular responses not only to ischemic stroke, but also to an early treatment with neurotrophic factors. Rats underwent 60 minutes of focal cerebral ischemia. Fluorescence labeling was applied to sections from brains perfused 7 days after ischemia. Analyses focused on NVU constituents including the vasculature, astrocytes and microglia in the ischemic striatum, the border zone and the contralateral hemisphere. In addition to histochemical signs of BBB breakdown, a strong up-regulation of collagen IV and microglia activation occurred within the ischemic core with simultaneous degradation of astrocytes and their endfeet. Activated astroglia were mainly depicted at the border zone in terms of a glial scar formation. Early treatment with pigment epithelium-derived factor (PEDF) resulted in an attenuation of the usually up-regulated collagen IV-immunoreactivity. However, glial activation was not influenced by treatment with PEDF or the epidermal growth factor (EGF). In conclusion, these data on ischemia-induced cellular reactions within the NVU might help to develop treatments addressing the transition from injury towards regeneration. Thereby, the integrity of the vasculature in close relation to neighboring structures like astrocytes appears as a promising target.

Ependimoma myxopapilar sacro gigante con osteolisis

PubMed Central

Ajler, Pablo; Landriel, Federico; Goldschmidt, Ezequiel; Campero, Álvaro; Yampolsky, Claudio

2014-01-01

Objetivo: la presentación de un caso de una paciente con un ependimoma sacro con extensa infiltración y destrucción ósea local. Descripción del caso: una mujer de 53 años acudió a la consulta por dolor lumbosacro y alteraciones sensitivas perineales y esfinterianas. La imágenes por Resonancia Magnética (IRM) y la Tomografía Axial Computada (TAC) mostraron una lesión expansiva gigante a nivel S2-S4 con extensa osteólisis e invasión de tejidos adyacentes. Se realizó una exéresis tumoral completa con mejoría del estatus funcional. La anatomía patológica informó ependimoma mixopapilar. Discusión: la extensión de la resección quirúrgica es el mejor predictor de buen pronóstico. El tratamiento radiante se reserva como opción adyuvante para las resecciones incompletas y recidiva tumoral. La quimioterapia sólo debería utilizarse en casos en que la cirugía y la radioterapia estén contraindicadas. Conclusión: Los ependimomas mixopapilares sacros con destrucción ósea y presentación intra y extradural son muy infrecuentes y deben ser tenidos en cuenta entre los diagnósticos diferenciales preoperatorios. Su resección total, siempre que sea posible, es la mejor alternativa terapéutica. PMID:25165615

Planificación Neuroquirúrgica con Software Osirix

PubMed Central

Jaimovich, Sebastián Gastón; Guevara, Martin; Pampin, Sergio; Jaimovich, Roberto; Gardella, Javier Luis

2014-01-01

Introducción: La individualidad anatómica es clave para reducir el trauma quirúrgico y obtener un mejor resultado. Actualmente, el avance en las neuroimágenes ha permitido objetivar esa individualidad anatómica, permitiendo planificar la intervención quirúrgica. Con este objetivo, presentamos nuestra experiencia con el software Osirix. Descripción de la técnica: Se presentan 3 casos ejemplificadores de 40 realizados. Caso 1: Paciente con meningioma de la convexidad parasagital izquierda en área premotora; Caso 2: Paciente con macroadenoma hipofisario, operada previamente por vía transeptoesfenoidal en otra institución con una resección parcial; Caso 3: Paciente con lesiones en pedúnculo cerebeloso medio bilateral. Se realizó la planificación prequirúrgica con el software OsiriX, fusionando y reconstruyendo en 3D las imágenes de TC e IRM, para analizar relaciones anatómicas, medir distancias, coordenadas y trayectorias, entre otras funciones. Discusión: El software OsiriX de acceso libre y gratuito permite al cirujano, mediante la fusión y reconstrucción en 3D de imágenes, analizar la anatomía individual del paciente y planificar de forma rápida, simple, segura y económica cirugías de alta complejidad. En el Caso 1 se pudo analizar las relaciones del tumor con las estructuras adyacentes para minimizar el abordaje. En el Caso 2 permitió comprender la anatomía post-operatoria previa del paciente, para determinar la trayectoria del abordaje transnasal endoscópico y la necesidad de ampliar su exposición, logrando la resección tumoral completa. En el Caso 3 permitió obtener las coordenadas estereotáxicas y trayectoria de una lesión sin representación tomográfica. Conclusión: En casos de no contar con costosos sistemas de neuronavegación o estereotáxia el software OsiriX es una alternativa a la hora de planificar la cirugía, con el objetivo de disminuir el trauma y la morbilidad operatoria. PMID:25165617

Pros and Cons of International Weapons Procurement Collaboration.

DTIC Science & Technology

1995-01-01

ad- vanced U.S. industry. Greater risk of cost growth and schedule slippage. Pro: U.S. and partners share common equip- ment. Con : U.S. require...Mark A., 1947- Pros and cons of international weapons procurement collaboration / Mark Lorell, Julia Lowell, p. cm "Prepared for the Office...one/ Cons of International Weapons Procurement Collaboration Mark Lorell Julia Lowell National Defense Research Institute Prepared for the

The human brain pacemaker: Synchronized infra-slow neurovascular coupling in patients undergoing non-pulsatile cardiopulmonary bypass.

PubMed

Zanatta, Paolo; Toffolo, Gianna Maria; Sartori, Elisa; Bet, Anna; Baldanzi, Fabrizio; Agarwal, Nivedita; Golanov, Eugene

2013-05-15

-slow oscillations in the brain is proposed. These findings allow to suggest an original hypothesis explaining the mechanism underlying infra-slow neurovascular coupling. Copyright © 2013 Elsevier Inc. All rights reserved.

Inversor Resonante de Tres Elementos L-LC con Caracteristica Cortocircuitable para Aplicaciones de Calentamiento por Induccion

NASA Astrophysics Data System (ADS)

Espi Huerta, Jose Miguel

Los generadores de calentamiento por induccion son puentes inversores con carga resonante, cuya mision es basicamente crear una corriente sinusoidal de gran amplitud sobre la "bobina de caldeo", que forma parte del tanque resonante. En el interior de esta bobina se introduce la pieza que se desea calentar. EI campo magnetico creado induce corrientes superficiales (corrientes de Foucault) sobre la pieza, que producen su calentamiento. Los tanques resonantes (tambien llamados osciladores) utilizados en la actualidad son el resonante serie y el resonante paralelo. Aunque ya desde hace algun tiempo se vienen construyendo generadores de alta potencia basados en estos dos osciladores, el exito nunca ha. sido completo en ninguno de los dos casos. Tal y como se explica en la introduccion de esta memoria, los puentes inversores utilizados deben operar sobre una carga inductiva (corriente retrasada) para evitar el fenomeno de la recuperacion inversa de sus diodos y la consiguiente ruptura de los transistores. De la restriccion topologica anterior se deduce que el generador paralelo debe conmutar a frecuencias inferiores a la resonancia, y el serie a frecuencias superiores. A esta restriccion topologica hay que unir otra que es exclusiva del calentamiento por induccion: La corriente por la bobina de caldeo debe ser sinusoidal. De no ser asi, resultaria imposible disponer toda la potencia de calentamiento sobre la pieza en el espesor requerido por la aplicacion. Como consecuencia, los inversores no pueden operar por debajo de la frecuencia de resonancia del oscilador, pues en ese caso se amplifican los armonicos de orden superior de la tension/corriente de entrada situados sobre la resonancia, con la consiguiente distorsion de la corriente de salida. La conjuncion de las dos restricciones anteriores obligan al inversor paralelo a funcionar a la frecuencia de resonancia del oscilador. Esto imposibilita un control por variacion de frecuencia, regulandose la potencia desde la

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

9 CFR 319.301 - Chili con carne with beans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Chili con carne with beans. 319.301 Section 319.301 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE... Dehydrated Meat Food Products § 319.301 Chili con carne with beans. Chili con carne with beans shall contain...

Galaxias australes con núcleo doble

NASA Astrophysics Data System (ADS)

Gimeno, G.; Díaz, R.; Carranza, G.

Se estudia una muestra de galaxias australes con núcleo doble a partir de una búsqueda extensiva en la literatura. Se analizan las características morfológicas, fotométricas y espectroscópicas de la muestra. Para algunas galaxias se han realizado observaciones con el espectrógrafo multifunción (EMF) de la Estación Astrofísica de Bosque Alegre a partir de las cuales se determinaron parámetros cinemáticos.

Expression of Iron-Related Proteins at the Neurovascular Unit Supports Reduction and Reoxidation of Iron for Transport Through the Blood-Brain Barrier.

PubMed

Burkhart, Annette; Skjørringe, Tina; Johnsen, Kasper Bendix; Siupka, Piotr; Thomsen, Louiza Bohn; Nielsen, Morten Schallburg; Thomsen, Lars Lykke; Moos, Torben

2016-12-01

The mechanisms for iron transport through the blood-brain barrier (BBB) remain a controversy. We analyzed for expression of mRNA and proteins involved in oxidation and transport of iron in isolated brain capillaries from dietary normal, iron-deficient, and iron-reverted rats. The expression was also investigated in isolated rat brain endothelial cells (RBECs) and in immortalized rat brain endothelial (RBE4) cells grown as monoculture or in hanging culture inserts with defined BBB properties. Transferrin receptor 1, ferrireductases Steap 2 and 3, divalent metal transporter 1 (DMT1), ferroportin, soluble and glycosylphosphatidylinositol (GPI)-anchored ceruloplasmin, and hephaestin were all expressed in brain capillaries in vivo and in isolated RBECs and RBE4 cells. Gene expression of DMT1, ferroportin, and soluble and GPI-anchored ceruloplasmin were significantly higher in isolated RBECs with induced BBB properties. Primary pericytes and astrocytes both expressed ceruloplasmin and hephaestin, and RBECs, pericytes, and astrocytes all exhibited ferrous oxidase activity. The coherent protein expression of these genes was demonstrated by immunocytochemistry. The data show that brain endothelial cells provide the machinery for receptor-mediated uptake of ferric iron-containing transferrin. Ferric iron can then undergo reduction to ferrous iron by ferrireductases inside endosomes followed by DMT1-mediated pumping into the cytosol and subsequently cellular export by ferroportin. The expression of soluble ceruloplasmin by brain endothelial cells, pericytes, and astrocytes that together form the neurovascular unit (NVU) provides the ferroxidase activity necessary to reoxidize ferrous iron once released inside the brain.

Assessment of Dual-Antiplatelet Regimen for Pipeline Embolization Device Placement: A Survey of Major Academic Neurovascular Centers in the United States.

PubMed

Gupta, Raghav; Moore, Justin M; Griessenauer, Christoph J; Adeeb, Nimer; Patel, Apar S; Youn, Roy; Poliskey, Karen; Thomas, Ajith J; Ogilvy, Christopher S

2016-12-01

Flow diversion with the Pipeline Embolization Device (PED) currently is adopted for treatment of a variety of intracranial aneurysms. The elevated risk of thromboembolic complications associated with the device necessitates the need for administration of antiplatelet agents. We sought to assess current dual-antiplatelet therapy practices patterns and their associated costs after PED placement. An online questionnaire that assessed dual-antiplatelet regimens after flow diversion for treatment of intracranial aneurysms was developed and disseminated to 80 neurosurgeons at major academic cerebrovascular centers. Pricing information from 2 of the largest prescription payers in Massachusetts was used to calculate the monthly cost of these agents. Twenty-six responses (32.5%) were received. All respondents (100%) affirmed using clopidogrel and aspirin dual-antiplatelet therapy as a first-line regimen. Twenty-three (88.5%) routinely use platelet function testing. Eleven respondents (42.3%) each identified that they administer aspirin/ticagrelor and aspirin/prasugrel to clopidogrel hypo- or nonresponders. For uninsured patients, prasugrel was found to have the highest cumulative monthly cost ($471), followed by ticagrelor ($396), clopidogrel ($149), and ticlopidine ($110). Significant heterogeneity in dual-antiplatelet regimens after PED placement and associated costs exists at major academic neurovascular centers. The most commonly used first-line dual-antiplatelet regimen consists of aspirin and clopidogrel. Two major alternate protocols involving ticagrelor and prasugrel are administered to clopidogrel hyporesponders. The optimal dual-antiplatelet regimen for patients with cerebrovascular conditions has not been established, given limited prospective data within the neurointerventional literature. Copyright © 2016 Elsevier Inc. All rights reserved.

Expansions of the Neurovascular Scleral Canal and Contained Optic Nerve Occur Early in the Hypertonic Saline Rat Experimental Glaucoma Model

PubMed Central

Pazos, Marta; Yang, Hongli; Gardiner, Stuart K.; Cepurna, W.O.; Johnson, E.C.; Morrison, J.C.; Burgoyne, Claude F.

2015-01-01

Purpose To characterize early optic nerve head (ONH) structural change in rat experimental glaucoma (EG). Methods Unilateral intraocular pressure (IOP) elevation was induced in Brown Norway rats by hypertonic saline injection into the episcleral veins and animals were sacrificed 4 weeks later by perfusion fixation. Optic nerve cross-sections were graded from 1 (normal) to 5 (extensive injury) by 5 masked observers. ONH’s with peripapillary retina and sclera were embedded, serial sectioned, 3-D reconstructed, delineated, and quantified. Overall and animal-specific EG versus Control eye ONH parameter differences were assessed globally and regionally by linear mixed effect models with significance criteria adjusted for multiple comparisons. Results Expansions of the optic nerve and surrounding anterior scleral canal opening achieved statistical significance overall (p<.0022), and in 7 of 8 EG eyes (p<.005). In at least 5 EG eyes, significant expansions (p<.005) in Bruch’s membrane opening (range 3–10%), the anterior and posterior scleral canal openings (8–21% and 5–21%, respectively), and the optic nerve at the anterior and posterior scleral canal openings (11–30% and 8–41%, respectively) were detected. Optic nerve expansion was greatest within the superior and inferior quadrants. Optic nerve expansion at the posterior scleral canal opening was significantly correlated to optic nerve damage (R= 0.768, P=.042). Conclusion In the rat ONH, the optic nerve and surrounding Bruch’s membrane opening and neurovascular scleral canal expand early in their response to chronic experimental IOP elevation. These findings provide phenotypic landmarks and imaging targets for detecting the development of experimental glaucomatous optic neuropathy in the rat eye. PMID:26500195

Expansions of the neurovascular scleral canal and contained optic nerve occur early in the hypertonic saline rat experimental glaucoma model.

PubMed

Pazos, Marta; Yang, Hongli; Gardiner, Stuart K; Cepurna, William O; Johnson, Elaine C; Morrison, John C; Burgoyne, Claude F

2016-04-01

To characterize early optic nerve head (ONH) structural change in rat experimental glaucoma (EG). Unilateral intraocular pressure (IOP) elevation was induced in Brown Norway rats by hypertonic saline injection into the episcleral veins and animals were sacrificed 4 weeks later by perfusion fixation. Optic nerve cross-sections were graded from 1 (normal) to 5 (extensive injury) by 5 masked observers. ONHs with peripapillary retina and sclera were embedded, serial sectioned, 3-D reconstructed, delineated, and quantified. Overall and animal-specific EG versus Control eye ONH parameter differences were assessed globally and regionally by linear mixed effect models with significance criteria adjusted for multiple comparisons. Expansions of the optic nerve and surrounding anterior scleral canal opening achieved statistical significance overall (p < 0.0022), and in 7 of 8 EG eyes (p < 0.005). In at least 5 EG eyes, significant expansions (p < 0.005) in Bruch's membrane opening (BMO) (range 3-10%), the anterior and posterior scleral canal openings (8-21% and 5-21%, respectively), and the optic nerve at the anterior and posterior scleral canal openings (11-30% and 8-41%, respectively) were detected. Optic nerve expansion was greatest within the superior and inferior quadrants. Optic nerve expansion at the posterior scleral canal opening was significantly correlated to optic nerve damage (R = 0.768, p = 0.042). In the rat ONH, the optic nerve and surrounding BMO and neurovascular scleral canal expand early in their response to chronic experimental IOP elevation. These findings provide phenotypic landmarks and imaging targets for detecting the development of experimental glaucomatous optic neuropathy in the rat eye. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Procurement of Non Developmental Items: Pros and Cons

DTIC Science & Technology

1994-09-01

commercial way of procurement will bring more advantages than disadvantages to DOD. The list of the pros greatly outweighs the cons . There is practically...AD-A285 009 MH PROCUREMENT OF NON DEVELOPMENTAL ITEMS: PROS AND CONS THES IS Giorgio Scappaticci. Lt. Col., Italian Air Force AFIT/GLMILALj94S-3 I...PROS AND CONS U;narmou,.ced 0 Justification THESIS Giorgio Scappaticci, Lt. Col., Italian Air Force Dist’ibution f Availability Codes AFIT/GLM/LAL

ConKit: a python interface to contact predictions.

PubMed

Simkovic, Felix; Thomas, Jens M H; Rigden, Daniel J

2017-07-15

Recent advances in protein residue contact prediction algorithms have led to the emergence of many new methods and a variety of file formats. We present ConKit , an open source, modular and extensible Python interface which allows facile conversion between formats and provides an interface to analyses of sequence alignments and sets of contact predictions. ConKit is available via the Python Package Index. The documentation can be found at http://www.conkit.org . ConKit is licensed under the BSD 3-Clause. hlfsimko@liverpool.ac.uk or drigden@liverpool.ac.uk. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

ComSciCon: The Communicating Science Workshop for Graduate Students

NASA Astrophysics Data System (ADS)

Sanders, Nathan; Drout, Maria; Kohler, Susanna; Cook, Ben; ComSciCon Leadership Team

2018-01-01

ComSciCon (comscicon.com) is a national workshop series organized by graduate students, for graduate students, focused on leadership and training in science communication. Our goal is to empower young scientists to become leaders in their field, propagating appreciation and understanding of research results to broad and diverse audiences. ComSciCon attendees meet and interact with professional communicators, build lasting networks with graduate students in all fields of science and engineering from around the country, and write and publish original works. ComSciCon consists of both a flagship national conference series run annually for future leaders in science communication, and a series of regional and specialized workshops organized by ComSciCon alumni nationwide. We routinely receive over 1000 applications for 50 spots in our national workshop. Since its founding in 2012, over 300 STEM graduate students have participated in the national workshop, and 23 local spin-off workshops have been organized in 10 different locations throughout the country. This year, ComSciCon is working to grow as a self-sustaining organization by launching as an independent 501(c)(3) non-profit. In this poster we will discuss the ComSciCon program and methods, our results to date, potential future collaborations between ComSciCon and AAS, and how you can become involved.

Trazando la materia oscura con cúmulos globulares

NASA Astrophysics Data System (ADS)

Forte, J. C.

Se describe la estrategia adoptada para mapear la distribución de materia oscura y bariónica en galaxias elípticas cuyos cúmulos globulares están siendo observados con los telescopios VLT y Gemini. Se ejemplifican los resultados con los datos obtenidos en el cúmulo de Fornax.

Protein Supplements: Pros and Cons.

PubMed

Samal, Jay Rabindra Kumar; Samal, Indira R

2018-05-04

To provide a comprehensive analysis of the literature examining the pros and cons of protein supplementation, various articles on protein supplementation were obtained from Google Scholar, PubMed, and National Center for Biotechnology Information. Over the past few years, protein supplementation has become commonplace for gym-goers as well as for the public. A large segment of the general population relies on protein supplementation for meal replacement, weight reduction, and purported health benefits. These protein supplements have varying pros and cons associated with them, which are often overlooked by the public. This review aims to assimilate existing studies and form a consensus regarding the benefits and disadvantages of protein supplementation. The purported health benefits of protein supplementation have led to overuse by both adults and adolescents. Although the pros and cons of protein supplementation is a widely debated topic, not many studies have been conducted regarding the same. The few studies that exist either provide insufficient evidence or have not employed proper conditions for the conduct of the tests. It should be considered that protein supplements are processed materials and often do not contain other essential nutrients required for the sustenance of a healthy lifestyle. It is suggested that the required protein intake should be obtained from natural food sources and protein supplementation should be resorted to only if sufficient protein is not available in the normal diet.

ConSpeciFix: Classifying prokaryotic species based on gene flow.

PubMed

Bobay, Louis-Marie; Ellis, Brian Shin-Hua; Ochman, Howard

2018-05-16

Classification of prokaryotic species is usually based on sequence similarity thresholds, which are easy to apply but lack a biologically-relevant foundation. Here, we present ConSpeciFix, a program that classifies prokaryotes into species using criteria set forth by the Biological Species Concept, thereby unifying species definition in all domains of life. ConSpeciFix's webserver is freely available at www.conspecifix.com. The local version of the program can be freely downloaded from https://github.com/Bobay-Ochman/ConSpeciFix. ConSpeciFix is written in Python 2.7 and requires the following dependencies: Usearch, MCL, MAFFT and RAxML. ljbobay@uncg.edu.

Neurovascular coupling protects neurons against hypoxic injury via inhibition of potassium currents by generation of nitric oxide in direct neuron and endothelium cocultures.

PubMed

Wu, Kun-Wei; Kou, Zeng-Wei; Mo, Jia-Lin; Deng, Xu-Xu; Sun, Feng-Yan

2016-10-15

This study examined the effect of neuron-endothelial coupling on the survival of neurons after ischemia and the possible mechanism underlying that effect. Whole-cell patch-clamp experiments were performed on cortical neurons cultured alone or directly cocultured with brain microvascular endothelial cells (BMEC). Propidium iodide (PI) and NeuN staining were performed to examine neuronal death following oxygen and glucose deprivation (OGD). We found that the neuronal transient outward potassium currents (I A ) decreased in the coculture system, whereas the outward delayed-rectifier potassium currents (I K ) did not. Sodium nitroprusside, a NO donor, enhanced BMEC-induced I A inhibition and nitro-l-arginine methylester, a NOS inhibitor, partially prevented this inhibition. Moreover, the neurons directly cocultured with BMEC showed more resistance to OGD-induced injury compared with the neurons cultured alone, and that neuroprotective effect was abolished by treatment with NS5806, an activator of the I A . These results indicate that vascular endothelial cells assist neurons to prevent hypoxic injury via inhibiting neuronal I A by production of NO in the direct neuron-BMEC coculture system. These results further provide direct evidence of functional coupling between neurons and vascular endothelial cells. This study clearly demonstrates that vascular endothelial cells play beneficial roles in the pathophysiological processes of neurons after hypoxic injury, suggesting that the improvement of neurovascular coupling or functional remodeling may become an important therapeutic target for preventing brain injury. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Games Con Men Play: The Semiosis of Deceptive Interaction.

ERIC Educational Resources Information Center

Hankiss, Agnes

1980-01-01

Analyzes some of the most frequent deceptive interactions as rendered through case histories of male con artists and their victims taken from police records. Discusses the recurrent elements in both the con-games strategies and victims' way of interpreting those strategies. (JMF)

Breath Analysis Science at PittCon 2012, Orlando, Florida

EPA Science Inventory

Breath analysis science was featured in three organized sessions at this year’s Pittsburgh Conference and Exposition, or ‘PittCon 2012’ (http://www.pittcon.org/). As described in previous meeting reports, PittCon is one of the largest international conferences for analytical chem...

Rapid Postnatal Expansion of Neural Networks Occurs in an Environment of Altered Neurovascular and Neurometabolic Coupling.

PubMed

Kozberg, Mariel G; Ma, Ying; Shaik, Mohammed A; Kim, Sharon H; Hillman, Elizabeth M C

2016-06-22

In the adult brain, increases in neural activity lead to increases in local blood flow. However, many prior measurements of functional hemodynamics in the neonatal brain, including functional magnetic resonance imaging (fMRI) in human infants, have noted altered and even inverted hemodynamic responses to stimuli. Here, we demonstrate that localized neural activity in early postnatal mice does not evoke blood flow increases as in the adult brain, and elucidate the neural and metabolic correlates of these altered functional hemodynamics as a function of developmental age. Using wide-field GCaMP imaging, the development of neural responses to somatosensory stimulus is visualized over the entire bilaterally exposed cortex. Neural responses are observed to progress from tightly localized, unilateral maps to bilateral responses as interhemispheric connectivity becomes established. Simultaneous hemodynamic imaging confirms that spatiotemporally coupled functional hyperemia is not present during these early stages of postnatal brain development, and develops gradually as cortical connectivity is established. Exploring the consequences of this lack of functional hyperemia, measurements of oxidative metabolism via flavoprotein fluorescence suggest that neural activity depletes local oxygen to below baseline levels at early developmental stages. Analysis of hemoglobin oxygenation dynamics at the same age confirms oxygen depletion for both stimulus-evoked and resting-state neural activity. This state of unmet metabolic demand during neural network development poses new questions about the mechanisms of neurovascular development and its role in both normal and abnormal brain development. These results also provide important insights for the interpretation of fMRI studies of the developing brain. This work demonstrates that the postnatal development of neuronal connectivity is accompanied by development of the mechanisms that regulate local blood flow in response to neural

PubMed

Soriguer, Federico

2016-11-29

Desde hace algún tiempo sabemos que la talla de las poblaciones es un buen instrumento para analizar la evolución socioeconómica, habiendo dejado de ser motivo de estudio solo por la biomedicina para serlo también por los economistas y sociólogos. Es lo que han hecho Martínez Carrión y cols., con el trabajo que aparece en este número de Nutrición Hospitalaria.

Functional outcomes of Gartland III supracondylar humerus fractures with early neurovascular complications in children: A retrospective observational study.

PubMed

Wang, Sung Il; Kwon, Tae Young; Hwang, Hong Pil; Kim, Jung Ryul

2017-06-01

This was a retrospective observational study. The aim of this study was to evaluate functional outcomes in children treated for Gartland III supracondylar humerus (SCH) fracture with neurovascular (NV) injuries using validated outcome measures. A secondary goal was to determine whether clinical parameters such as age at injury, sex, weight, fracture site, and/or direction of displacement could predict NV injury at the time of fracture or long-term functional outcomes in these patients.One hundred fifty-four patients of Gartland III SCH fractures between March 2004 and May 2013 were studied retrospectively. The patients were divided into 2 groups according to the presence of NV injury. Medical records and radiographs were reviewed to assess several parameters, including age, sex, weight, treatment intervention, the extremity involved, direction of fracture displacement, and NV injury. Functional outcome was assessed on final follow-up using the Pediatric Outcomes Data Collection Instrument (PODCI) and Quick Disabilities of the Arm, Shoulder, and Hand (Quick DASH) outcome measures. Statistical analysis was used to determine the relationship between NV injury and functional outcomes.There were 33 cases with Gartland III SCH fracture associated with NV injuries (10 cases of vascular compromise, 14 cases of neural injury, and 9 cases involving both vascular compromise and neural injury). There were significant differences between the 2 groups in age (P  =  .048), weight (P  =  .009), and direction of displacement (P  =  .004). Vascular compromise and median nerve injury were most common in fractures with posterolateral displacement, and radial nerve injuries were common in fractures with posteromedial displacement. The mean global function score in the PODCI was 91.4 points, and the mean Quick DASH score was 11.7 points, with excellent functional outcomes. No differences in outcomes were identified based upon age, fracture site, sex, weight, direction of

Calcaneal traction pin placement simplified: a cadaveric study.

PubMed

Kwon, John Y; Ellington, J Kent; Marsland, Daniel; Gupta, Sanjeev

2011-06-01

The tibial neurovascular bundle and sural nerve are at risk with errant pin placement during transcalcaneal pin placement. The purpose of this study was to determine a relative safe zone using a single osseous landmark to establish a technique applicable in the presence of trauma. We describe the neural anatomy anatomically and radiographically, giving surgeons a reliable and relatively safe technique for transcalcaneal pin placement. Twenty-four cadavers were dissected for the major medial neurovascular structures and the sural nerve. The closest distance from the neurovascular structures to the posterior inferior calcaneus was measured. The mean distance from the posterior inferior calcaneus to the closest major medial neurovascular structure was 3.4 cm (SD ± 0.36; range, 2.6 to 4.1 cm). The mean distance to the sural nerve was 3.4 cm (SD ± 0.54; range, 2.3 to 4.6 cm). According to the 95% confidence intervals, a relative safe zone of 3.1 cm as a radius from the posterior inferior calcaneus was determined. A relatively safe zone of 3.1 cm based on 95% confidence intervals as described as a radius from the posterior inferior calcaneus can be used for transcalcaneal pin placement in most cases without injury to the medial neurovascular bundle or sural nerve. However anatomic variation may result in the neurovascular bundle being within this zone. We describe a surgical technique for reliable placement of a transcalcaneal pin within this relative safe zone and a safe distance from the closest neurovascular structure.

High-resolution STIR for 3-T MRI of the posterior fossa: visualization of the lower cranial nerves and arteriovenous structures related to neurovascular compression.

PubMed

Hiwatashi, Akio; Yoshiura, Takashi; Yamashita, Koji; Kamano, Hironori; Honda, Hiroshi

2012-09-01

Preoperative evaluation of small vessels without contrast material is sometimes difficult in patients with neurovascular compression disease. The purpose of this retrospective study was to evaluate whether 3D STIR MRI could simultaneously depict the lower cranial nerves--fifth through twelfth--and the blood vessels in the posterior fossa. The posterior fossae of 47 adults (26 women, 21 men) without gross pathologic changes were imaged with 3D STIR and turbo spin-echo heavily T2-weighted MRI sequences and with contrast-enhanced turbo field-echo MR angiography (MRA). Visualization of the cranial nerves on STIR images was graded on a 4-point scale and compared with visualization on T2-weighted images. Visualization of the arteries on STIR images was evaluated according to the segments in each artery and compared with that on MRA images. Visualization of the veins on STIR images was also compared with that on MRA images. Statistical analysis was performed with the Mann-Whitney U test. There were no significant differences between STIR and T2-weighted images with respect to visualization of the cranial nerves (p > 0.05). Identified on STIR and MRA images were 94 superior cerebellar arteries, 81 anteroinferior cerebellar arteries, and 79 posteroinferior cerebellar arteries. All veins evaluated were seen on STIR and MRA images. There were no significant differences between STIR and MRA images with respect to visualization of arteries and veins (p > 0.05). High-resolution STIR is a feasible method for simultaneous evaluation of the lower cranial nerves and the vessels in the posterior fossa without the use of contrast material.

2D and 3D T2-weighted MR sequences for the assessment of neurovascular bundle changes after nerve-sparing radical retropubic prostatectomy with erectile function correlation.

PubMed

Panebianco, Valeria; Sciarra, Alessandro; Osimani, Marcello; Lisi, Danilo; Ciccariello, Mauro; Salciccia, Stefano; Gentile, Vincenzo; Di Silverio, Franco; Passariello, Roberto

2009-01-01

The aim of this study was to assess the capability of a 3D isotropic MRI T2-weighted sequence (3D T2 ISO) in the depiction of changes of neurovascular bundles (NVBs) after bilateral nerve-sparing radical retropubic prostatectomy (RRP). Furthermore, our aim was also to introduce a new MRI classification score of the NVB alteration patterns using the International Index Erectile Function Five-Item (IIEF-5) score as standard of reference. Fifty-three consecutive patients were postoperatively submitted to two MR examinations, including both 2D TSE T2-weighted (2D T2) and 3D T2 ISO sequences. Image findings were scored using a relative five-point classification and correlated with the postoperative IIEF-5 score. Radiologists attributed 13.2% of patients to class 0, 11.3% to class I, 34% to class II, 24.5% to class III, and 16.9% to class IV. With 3D T2 ISO images, the same radiologists determined 43.3% class 0, 32% class I, 11.4% class II, 7.5% class III, and 5.7% class IV. In all cases, the correlation and regression analysis between the 3D T2 ISO and IIEF-5 score resulted in higher coefficients values. The 3D sequence correlated most closely with patients' grading of erectile function.

Neurovascular control during exercise in acute coronary syndrome patients with Gln27Glu polymorphism of β2-adrenergic receptor

PubMed Central

Ferreira-Santos, Larissa; Martinez, Daniel G.; Nicolau, José Carlos; Moreira, Humberto G.; Alves, Maria Janieire; Pereira, Alexandre C.; Trombetta, Ivani C.; Negrão, Carlos Eduardo

2017-01-01

Background Gln27Glu (rs1042714) polymorphism of the β2-adrenergic receptor (ADRB2) has been association with cardiovascular functionality in healthy subjects. However, it is unknown whether the presence of the ADRB2 Gln27Glu polymorphism influences neurovascular responses during exercise in patients with acute coronary syndromes (ACS). We tested the hypothesis that patients with ACS homozygous for the Gln allele would have increased muscle sympathetic nerve activity (MSNA) responses and decreased forearm vascular conductance (FVC) responses during exercise compared with patients carrying the Glu allele (Gln27Glu and Glu27Glu). In addition, exercise training would restore these responses in Gln27Gln patients. Methods and results Thirty-days after an ischemic event, 61 patients with ACS without ventricular dysfunction were divided into 2 groups: (1) Gln27Gln (n = 35, 53±1years) and (2) Gln27Glu+Glu27Glu (n = 26, 52±2years). MSNA was directly measured using the microneurography technique, blood pressure (BP) was measured with an automatic oscillometric device, and blood flow was measured using venous occlusion plethysmography. MSNA, mean BP, and FVC were evaluated at rest and during a 3-min handgrip exercise. The MSNA (P = 0.02) and mean BP (P = 0.04) responses during exercise were higher in the Gln27Gln patients compared with that in the Gln27Glu+Glu27Glu patients. No differences were found in FVC. Two months of exercise training significantly decreased the MSNA levels at baseline (P = 0.001) and in their response during exercise (P = 0.02) in Gln27Gln patients, but caused no changes in Gln27Glu+Glu27Glu patients. Exercise training increased FVC responses in Gln27Glu+Glu27Glu patients (P = 0.03), but not in Gln27Gln patients. Conclusion The exaggerated MSNA and mean BP responses during exercise suggest an increased cardiovascular risk in patients with ACS and Gln27Gln polymorphism. Exercise training emerges as an important strategy for restoring this reflex

Spatial scale and distribution of neurovascular signals underlying decoding of orientation and eye of origin from fMRI data

PubMed Central

Harrison, Charlotte; Jackson, Jade; Oh, Seung-Mock; Zeringyte, Vaida

2016-01-01

Multivariate pattern analysis of functional magnetic resonance imaging (fMRI) data is widely used, yet the spatial scales and origin of neurovascular signals underlying such analyses remain unclear. We compared decoding performance for stimulus orientation and eye of origin from fMRI measurements in human visual cortex with predictions based on the columnar organization of each feature and estimated the spatial scales of patterns driving decoding. Both orientation and eye of origin could be decoded significantly above chance in early visual areas (V1–V3). Contrary to predictions based on a columnar origin of response biases, decoding performance for eye of origin in V2 and V3 was not significantly lower than that in V1, nor did decoding performance for orientation and eye of origin differ significantly. Instead, response biases for both features showed large-scale organization, evident as a radial bias for orientation, and a nasotemporal bias for eye preference. To determine whether these patterns could drive classification, we quantified the effect on classification performance of binning voxels according to visual field position. Consistent with large-scale biases driving classification, binning by polar angle yielded significantly better decoding performance for orientation than random binning in V1–V3. Similarly, binning by hemifield significantly improved decoding performance for eye of origin. Patterns of orientation and eye preference bias in V2 and V3 showed a substantial degree of spatial correlation with the corresponding patterns in V1, suggesting that response biases in these areas originate in V1. Together, these findings indicate that multivariate classification results need not reflect the underlying columnar organization of neuronal response selectivities in early visual areas. NEW & NOTEWORTHY Large-scale response biases can account for decoding of orientation and eye of origin in human early visual areas V1–V3. For eye of origin this pattern

Neurovascular control during exercise in acute coronary syndrome patients with Gln27Glu polymorphism of β2-adrenergic receptor.

PubMed

Ferreira-Santos, Larissa; Martinez, Daniel G; Nicolau, José Carlos; Moreira, Humberto G; Alves, Maria Janieire; Pereira, Alexandre C; Trombetta, Ivani C; Negrão, Carlos Eduardo; Rondon, Maria Urbana P B

2017-01-01

Gln27Glu (rs1042714) polymorphism of the β2-adrenergic receptor (ADRB2) has been association with cardiovascular functionality in healthy subjects. However, it is unknown whether the presence of the ADRB2 Gln27Glu polymorphism influences neurovascular responses during exercise in patients with acute coronary syndromes (ACS). We tested the hypothesis that patients with ACS homozygous for the Gln allele would have increased muscle sympathetic nerve activity (MSNA) responses and decreased forearm vascular conductance (FVC) responses during exercise compared with patients carrying the Glu allele (Gln27Glu and Glu27Glu). In addition, exercise training would restore these responses in Gln27Gln patients. Thirty-days after an ischemic event, 61 patients with ACS without ventricular dysfunction were divided into 2 groups: (1) Gln27Gln (n = 35, 53±1years) and (2) Gln27Glu+Glu27Glu (n = 26, 52±2years). MSNA was directly measured using the microneurography technique, blood pressure (BP) was measured with an automatic oscillometric device, and blood flow was measured using venous occlusion plethysmography. MSNA, mean BP, and FVC were evaluated at rest and during a 3-min handgrip exercise. The MSNA (P = 0.02) and mean BP (P = 0.04) responses during exercise were higher in the Gln27Gln patients compared with that in the Gln27Glu+Glu27Glu patients. No differences were found in FVC. Two months of exercise training significantly decreased the MSNA levels at baseline (P = 0.001) and in their response during exercise (P = 0.02) in Gln27Gln patients, but caused no changes in Gln27Glu+Glu27Glu patients. Exercise training increased FVC responses in Gln27Glu+Glu27Glu patients (P = 0.03), but not in Gln27Gln patients. The exaggerated MSNA and mean BP responses during exercise suggest an increased cardiovascular risk in patients with ACS and Gln27Gln polymorphism. Exercise training emerges as an important strategy for restoring this reflex control. Gln27Glu polymorphism of ADRB2

2-(2-Benzofuranyl)-2-Imidazoline Mediates Neuroprotection by Regulating the Neurovascular Unit Integrity in a Rat Model of Focal Cerebral Ischemia.

PubMed

Zhang, Zheng; Zhang, Linlei; Chen, Jiaou; Cao, Yungang; Qu, Man; Lin, Xinda; Han, Zhao; Ji, Xunming

2018-06-01

We showed previously that 2-(2-benzofuranyl)-2-imidazoline (2-BFI), a ligand to type 2 imidazoline receptor (I2R) exerts neuroprotective effects in ischemia stroke via an unknown mechanism. The present study was to investigate whether 2-BFI can protect the neurovascular unit (NVU) using a rat model of 90 min focal cerebral ischemia. Rats were randomly divided into three groups: thesham-operated group; the vehicle control group and the 2-BFI group which received 2-BFI (3 mg/kg) immediately after the start of middle cerebralartery occlusion (MCAO). Neurological deficit score, infarct size, apoptosis level, brain water content and Evans Blue extravasation were assessed at 24 h after stroke. Expressions of occludin and zonula occludens 1 (ZO-1), collagen IV, aquaporin-4 (AQP-4), matrix metalloproteinase-9 (MMP-9) and MMP-2 were assessed by Western blotting. 2-BFI treatment was associated with significant improvement of neurological performance and decreased infarct volume at 24 h after stroke. Apoptosis level reduced significantly by 2-BFI compared to the vehicle group (34.3 ± 5.4% vs 56.1 ± 7.9%, p < 0.05). Significant decreased of brain water content (79.5 ± 2.6% vs 84.62 ± 2%, p < 0.05) and Evans Blue extravasation (1.2 ± 0.5 vs 2.5 ± 0.41 µg/g, p < 0.05) of ipsilateral hemisphere was observed in 2-BFI group compared to vehicle group. Expressions of occludin, ZO-1 and collagen IV were significantly higher while MMP-9 level significantly lower in 2-BFI group. AQP-4 and MMP-2 showed no difference between 2-BFI and the vehicle groups. These results suggest that the neuroprotective effects of 2-BFI in acute ischemic brain damage are at least partly due to the drug's ability to improve the functions of NVU. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

ConsPred: a rule-based (re-)annotation framework for prokaryotic genomes.

PubMed

Weinmaier, Thomas; Platzer, Alexander; Frank, Jeroen; Hellinger, Hans-Jörg; Tischler, Patrick; Rattei, Thomas

2016-11-01

The rapidly growing number of available prokaryotic genome sequences requires fully automated and high-quality software solutions for their initial and re-annotation. Here we present ConsPred, a prokaryotic genome annotation framework that performs intrinsic gene predictions, homology searches, predictions of non-coding genes as well as CRISPR repeats and integrates all evidence into a consensus annotation. ConsPred achieves comprehensive, high-quality annotations based on rules and priorities, similar to decision-making in manual curation and avoids conflicting predictions. Parameters controlling the annotation process are configurable by the user. ConsPred has been used in the institutions of the authors for longer than 5 years and can easily be extended and adapted to specific needs. The ConsPred algorithm for producing a consensus from the varying scores of multiple gene prediction programs approaches manual curation in accuracy. Its rule-based approach for choosing final predictions avoids overriding previous manual curations. ConsPred is implemented in Java, Perl and Shell and is freely available under the Creative Commons license as a stand-alone in-house pipeline or as an Amazon Machine Image for cloud computing, see https://sourceforge.net/projects/conspred/. thomas.rattei@univie.ac.atSupplementary information: Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

InterCon Travel Health: Case B

ERIC Educational Resources Information Center

Truman, Gregory E.; Pachamanova, Dessislava A.; Goldstein, Michael A.

2010-01-01

InterCon provides services to health insurers of foreign tourists who travel to the United States and Canada. Management wants to implement a new information system that will deal with several operational problems, but it is having difficulty securing the capital resources to fund the system's development. After an initial failure, the chief…

Impact of the ConRed program on different cyberbulling roles.

PubMed

Del Rey, Rosario; Casas, José A; Ortega, Rosario

2016-01-01

This article presents results from an evaluation of the ConRed cyberbullying intervention program. The program's impacts were separately determined for the different roles within cyberbullying that students can take, i.e., cyber-victims, cyber-bullies, cyber-bully/victims, and bystanders. The ConRed program is a theory-driven program designed to prevent cyberbullying and improve cyberbullying coping skills. It involves students, teachers, and families. During a 3-month period, external experts conducted eight training sessions with students, two with teachers and one with families. ConRed was evaluated through a quasi-experimental design, in which students from three secondary schools were separated into experimental and control groups. The sample comprised 875 students, aged between 11 and 19 years. More students (n = 586) were allocated to the experimental groups at the specific insistence of the management of all schools; the remainder (n = 289) formed the control. Repeated measures MANOVA showed that cyber victims, cyber aggressors and cyberbully/victims reduced their involvement in cyberbullying. Moreover, cyber-victims and bystanders adjusted their perceptions about their control of personal information on the Internet, and cyber aggressors and bystanders reduced their Internet dependence. The ConRed program had stronger effects on male participants, especially in heightening their affective empathy. © 2015 Wiley Periodicals, Inc.

El efecto de la panfotocoagulación con láser en edema macular diabético con el fotocoagulador Pascal® versus el láser de argón convencional.

PubMed

Mahgoub, Mohamed M; Macky, Tamer A

2017-07-11

Objetivo: El objetivo de este estudio fue comparar el efecto de la panfotocoagulación (PFC) en el edema macular diabético (EMD) en pacientes con retinopatía diabética proliferativa (RDP) con el fotocoagulador Pascal® (FP) vs. un fotocoagulador con láser de argón convencional (FLAC). Métodos: Se aleatorizó el uso de FP o FLAC en ochenta ojos con RDP y EMD con afectación central de la mácula. Ambos grupos tuvieron una evaluación de base de mejor agudeza visual corregida y fueron examinados con tomografía de coherencia óptica y angiografía con fluoresceína. Resultados: El número medio de disparos de láser en los grupos de FP y FLAC fue 1.726,10 y 752,00 en la sesión 1 y 1.589,00 y 830,00 (p < 0,001) en la sesión 2, respectivamente. El grosor foveal central (GFC) medio antes de comenzar el estudio fue 306 ± 100 y 314 ± 98 en los grupos de FP y FLAC, respectivamente. A las 8 semanas, el GFC medio fue 332 ± 116 y 347 ± 111 en los grupos de FP y FLAC, respectivamente (p > 0,05). La MAVC media fue similar durante el periodo de estudio y no hubo ninguna diferencia significativa entre los grupos (p > 0,05). Conclusiones: El FP y el FLAC mostraron efectos similares en el EMD en ojos con RDP y fueron igualmente seguros sin un aumento significativo del GFC. © 2017 S. Karger AG, Basel.

Meeting Report: Breath Biomarkers Networking Sessions at PittCon 2010, Orlando, Florida

EPA Science Inventory

The Pittsburgh Conference and Exposition, or "PittCon" (www.pittcon.org/), is one of the largest international conferences for analytical chemistry and instrumentation typically attracting about 25,000 attendees and 1,000 commercial exhibitors. PittCon began in 1950 as a small sp...

ConA-based glucose sensing using the long-lifetime azadioxatriangulenium fluorophore

NASA Astrophysics Data System (ADS)

Cummins, Brian; Simpson, Jonathan; Gryczynski, Zygmunt; Sørensen, Thomas Just; Laursen, Bo W.; Graham, Duncan; Birch, David; Coté, Gerard

2014-02-01

Fluorescent glucose sensing technologies have been identified as possible alternatives to current continuous glucose monitoring approaches. We have recently introduced a new, smart fluorescent ligand to overcome the traditional problems of ConA-based glucose sensors. For this assay to be translated into a continuous glucose monitoring device where both components are free in solution, the molecular weight of the smart fluorescent ligand must be increased. We have identified ovalbumin as a naturally-occurring glycoprotein that could serve as the core-component of a 2nd generation smart fluorescent ligand. It has a single asparagine residue that is capable of displaying an N-linked glycan and a similar isoelectric point to ConA. Thus, binding between ConA and ovalbumin can potentially be monovalent and sugar specific. This work is the preliminary implementation of fluorescently-labeled ovalbumin in the ConA-based assay. We conjugate the red-emitting, long-lifetime azadioxatriangulenium (ADOTA+) dye to ovalbumin, as ADOTA have many advantageous properties to track the equilibrium binding of the assay. The ADOTA-labeled ovalbumin is paired with Alexa Fluor 647-labeled ConA to create a Förster Resonance Energy Transfer (FRET) assay that is glucose dependent. The assay responds across the physiologically relevant glucose range (0-500 mg/dL) with increasing intensity from the ADOTA-ovalbumin, showing that the strategy may allow for the translation of the smart fluorescent ligand concept into a continuous glucose monitoring device.

ConTour: Data-Driven Exploration of Multi-Relational Datasets for Drug Discovery.

PubMed

Partl, Christian; Lex, Alexander; Streit, Marc; Strobelt, Hendrik; Wassermann, Anne-Mai; Pfister, Hanspeter; Schmalstieg, Dieter

2014-12-01

Large scale data analysis is nowadays a crucial part of drug discovery. Biologists and chemists need to quickly explore and evaluate potentially effective yet safe compounds based on many datasets that are in relationship with each other. However, there is a lack of tools that support them in these processes. To remedy this, we developed ConTour, an interactive visual analytics technique that enables the exploration of these complex, multi-relational datasets. At its core ConTour lists all items of each dataset in a column. Relationships between the columns are revealed through interaction: selecting one or multiple items in one column highlights and re-sorts the items in other columns. Filters based on relationships enable drilling down into the large data space. To identify interesting items in the first place, ConTour employs advanced sorting strategies, including strategies based on connectivity strength and uniqueness, as well as sorting based on item attributes. ConTour also introduces interactive nesting of columns, a powerful method to show the related items of a child column for each item in the parent column. Within the columns, ConTour shows rich attribute data about the items as well as information about the connection strengths to other datasets. Finally, ConTour provides a number of detail views, which can show items from multiple datasets and their associated data at the same time. We demonstrate the utility of our system in case studies conducted with a team of chemical biologists, who investigate the effects of chemical compounds on cells and need to understand the underlying mechanisms.

SLUDGE PARTICLE SEPAPATION EFFICIENCIES DURING SETTLER TANK RETRIEVAL INTO SCS-CON-230

DOE Office of Scientific and Technical Information (OSTI.GOV)

DEARING JI; EPSTEIN M; PLYS MG

2009-07-16

The purpose of this document is to release, into the Hanford Document Control System, FA1/0991, Sludge Particle Separation Efficiencies for the Rectangular SCS-CON-230 Container, by M. Epstein and M. G. Plys, Fauske & Associates, LLC, June 2009. The Sludge Treatment Project (STP) will retrieve sludge from the 105-K West Integrated Water Treatment System (IWTS) Settler Tanks and transfer it to container SCS-CON-230 using the Settler Tank Retrieval System (STRS). The sludge will enter the container through two distributors. The container will have a filtration system that is designed to minimize the overflow of sludge fines from the container to themore » basin. FAI/09-91 was performed to quantify the effect of the STRS on sludge distribution inside of and overflow out of SCS-CON-230. Selected results of the analysis and a system description are discussed. The principal result of the analysis is that the STRS filtration system reduces the overflow of sludge from SCS-CON-230 to the basin by roughly a factor of 10. Some turbidity can be expected in the center bay where the container is located. The exact amount of overflow and subsequent turbidity is dependent on the density of the sludge (which will vary with location in the Settler Tanks) and the thermal gradient between the SCS-CON-230 and the basin. Attachment A presents the full analytical results. These results are applicable specifically to SCS-CON-230 and the STRS filtration system's expected operating duty cycles.« less

Virulence, Speciation and Antibiotic Susceptibility of Ocular Coagualase Negative Staphylococci (CoNS)

PubMed Central

Priya, Ravindran; Mythili, Arumugam; Singh, Yendremban Randhir Babu; Sreekumar, Haridas; Manikandan, Palanisamy; Panneerselvam, Kanesan

2014-01-01

Background: Coagulase negative Staphylococci (CoNS) are common inhabitants of human skin and mucous membranes. With the emergence of these organisms as prominent pathogens in patients with ocular infections, investigation has intensified in an effort to identify important virulence factors and to inform new approaches to treatment and prevention. Aim: To isolate CoNS from ocular specimens; to study the possible virulence factors; speciation of coagulase negative staphylococci (CoNS) which were isolated from ocular complications; antibiotic susceptibility testing of ocular CoNS. Materials and Methods: The specimens were collected from the target patients who attended the Microbiology Laboratory of a tertiary care eye hospital in Coimbatore, Tamilnadu state, India. The isolates were subjected to tube and slide coagulase tests for the identification of CoNS. All the isolates were subjected to screening for lipase and protease activities. Screening for other virulence factors viz., slime production on Congo red agar medium and haemagglutination assay with use of 96-well microtitre plates. These isolates were identified upto species level by performing biochemical tests such as phosphatase test, arginine test, maltose and trehalose fermentation tests and novobiocin sensitivity test. The isolates were subjected to antibiotic susceptibility studies, based on the revised standards of Clinical and Laboratory Standards Institutes (CLSI). Results: During the one year of study, among the total 260 individuals who were screened, 100 isolates of CoNS were obtained. Lipolytic activity was seen in all the isolates, whereas 38 isolates showed a positive result for protease. A total of 63 isolates showed slime production. Of 100 isolates, 30 isolates were analyzed for haemagglutination, where 4 isolates showed the capacity to agglutinate the erythrocytes. The results of the biochemical analysis revealed that of the 100 isolates of CoNS, 43% were Staphylococcus epidermidis. The other

Spanish Summary (Nuevos meteoritos encountrados en lmilac)

NASA Astrophysics Data System (ADS)

1987-03-01

Desde tiempos prehistoricos han sido coleccionadas piedras que caen dei cielo. Hasta hace poco eran la unica fuente para hacer estudios de laboratorio de la materia extragal, ktica, e incluso en nuestra era espacial, siguen siendo una valiosa fuente de investigacion de la temprana historia dei sistema solar. Se estima que como termine medio cada kilometro cuadrado de la superficie terrestre es golpeada cada millon de aiios por un meteorito con un pese superior a 500 gramos. La mayoria se pierden en los oceanos 0 caen en regiones con escasa poblacion. Como resultado, los museos en el munda reciben anualmente tan solo alrededor de 6 meteoritos cuya caida fuera atestiguada. Otros llegan por hallazgos casuales que en la mayoria de los casos son meteoritos que han cardo en tiempos prehistoricos.

Association between silent embolic cerebral infarction and continuous increase of P2Y12 reaction units after neurovascular stenting.

PubMed

Kim, Bum Joon; Kwon, Joo Y; Jung, Jin-Man; Lee, Deok Hee; Kang, Dong-Wha; Kim, Jong S; Kwon, Sun U

2014-10-01

Endovascular procedures are one of the important treatment options for steno-occlusive arteries in ischemic stroke patients. However, embolic complications after such procedures are always a concern. The authors investigated the association between serial change of residual platelet reactivity and silent embolic cerebral infarction (SECI) after endovascular treatment. Ischemic stroke patients undergoing stenting of intra- or extracranial arteries were recruited prospectively. Residual platelet reactivity, represented by aspirin reaction units (ARUs) and P2Y12 reaction units (PRUs), was measured serially (6 hours before, immediately after, and 24 hours after the procedure). A loading dosage of aspirin (500 mg) and/or clopidogrel (300 mg) was given 24 hours before the procedure to patients naïve to antiplatelet agents, whereas the usual dosage (aspirin 100 mg and clopidogrel 75 mg) was continued for patients who had previously been taking these agents for more than a week. Diffusion-weighted MRI was performed before and 24 hours after the procedure to detect new SECIs. Clinical characteristics, baseline ARU and PRU values, and the change in ARU and PRU values after stenting were compared between patients with and without SECIs. Among 69 consecutive patients who underwent neurovascular stent insertion, 41 patients (59.4%) had poststenting SECIs. The lesion was located only at the vascular territory of the stented vessel in 21 patients (51.2%), outside the stented vessel territory in 8 patients (19.5%), and both inside and outside in 12 patients (29.3%). The occurrence of SECIs was not associated with the baseline ARU or PRU value, but was associated with PRU increase after stenting (36 ± 73 vs -12 ± 59, p = 0.007), deployment of a longer stent (31.1 ± 16.5 mm vs 21.8 ± 9.9 mm, p = 0.01), and stent insertion in extracranial arteries (78.1% vs 45.2%, p = 0.008). Stent length (OR 1.066, p = 0.01) and PRU change (OR 1.009, p = 0.04) were independently associated with

Anatomical feasibility study of flexor hallucis longus transfer in treatment of Achilles tendon and posteromedial portal of ankle arthroscopy.

PubMed

Mao, Haijiao; Wang, Linger; Dong, Wenwei; Liu, Zhenxin; Yin, Weigang; Xu, Dachuan; Wapner, Keith L

2018-04-16

The aim of this study was to evaluate the occurrence of anatomical variations of the musculotendinous junction of the flexor hallucis longus (FHL) muscle, the relationship between FHL tendon or muscle and the tibial neurovascular bundle at the level of the posterior ankle joint in human cadavers. Seventy embalmed feet from 20 male and 15 female cadavers, the cadavers' mean age was 65.4 (range from 14 to 82) years, were dissected and anatomically classified to observe FHL muscle morphology define the relationship between FHL tendon or muscle and the tibial neurovascular bundle. The distance between the musculotendinous junction and the relationship between FHL tendon or muscle and the tibial neurovascular bundle was determined. Three morphology types of FHL muscle were identified: a long lateral and shorter medial muscle belly, which was observed in 63 specimens (90%); equal length medial and lateral muscle bellies, this variant was only observed in five specimens (7.1%); one lateral and no medial muscle belly, which was observed in two specimens (2.9%). No statistically significant difference was observed according to gender or side (p > 0.05). Two patterns were identified and described between FHL tendon or muscle and the tibial neurovascular bundle. Pattern 1, the distance between the neurovascular bundle and FHL tendon was 3.46 mm (range 2.34-8.84, SD = 2.12) which was observed in 66 specimens (94.3%); Pattern 2, there was no distance which was observed in four specimens (5.7%). Knowing FHL muscle morphology, variations provide new important insights into secure planning and execution of a FHL transfer for Achilles tendon defect as well as for the interpretation of ultrasound and magnetic resonance images. With posterior arthroscopic for the treatment of various ankle pathologies, posteromedial portal may be introduced into the posterior aspect of the ankle without gross injury to the tibial neurovascular structures because of the gap between the

Sistemas de cúmulos globulares extragalácticos

NASA Astrophysics Data System (ADS)

Forte, J. C.

Se describen las características de los sistemas de cúmulos globulares asociados a galaxias elípticas en una variedad de medios y, en particular, aquellas vinculadas con la distribución espacial, frecuencia específica y composición química. Esta discusión se hace dentro de un conjunto de esquemas orientados a explicar las primeras fases de la formación de las galaxias dominantes en cúmulos y del rol de los sistemas de cúmulos globulares en esos procesos.

Enrichment of Glycoproteins using Nano-scale Chelating Con A Monolithic Capillary Chromatography

PubMed Central

Feng, Shun; Yang, Na; Pennathur, Subramaniam; Goodison, Steve; Lubman, David M.

2009-01-01

Immobilized lectin chromatography can be employed for glycoprotein enrichment, but commonly used columns have limitations of yield and resolution. In order to improve efficiency and to make the technique applicable to minimal sample material, we have developed a nano-scale chelating Concanavalin A (Con A) monolithic capillary prepared using GMA-EDMA (glycidyl methacrylate–co-ethylene dimethacrylate) as polymeric support. Con A was immobilized on Cu(II)-charged iminodiacetic acid (IDA) regenerable sorbents by forming a IDA:Cu(II):Con A sandwich affinity structure that has high column capacity as well as stability. When compared with conventional Con A lectin chromatography, the monolithic capillary enabled the better reproducible detection of over double the number of unique N-glycoproteins in human urine samples. Utility for analysis of minimal biological samples was confirmed by the successful elucidation of glycoprotein profiles in mouse urine samples at the microliter scale. The improved efficiency of the nano-scale monolithic capillary will impact the analysis of glycoproteins in complex biological samples, especially where only limited material may be available. PMID:19366252

9 CFR 319.300 - Chili con carne.

Code of Federal Regulations, 2011 CFR

2011-01-01

... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Canned, Frozen, or Dehydrated Meat Food... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Chili con carne. 319.300 Section 319.300 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY...

9 CFR 319.300 - Chili con carne.

Code of Federal Regulations, 2010 CFR

2010-01-01

... CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Canned, Frozen, or Dehydrated Meat Food... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Chili con carne. 319.300 Section 319.300 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY...

Optimizing Electrospray Interfaces Using Slowly Diverging Conical Duct (ConDuct) Electrodes

PubMed Central

Krutchinsky, Andrew N.; Padovan, Júlio C.; Cohen, Herbert; Chait, Brian T.

2015-01-01

We demonstrate that the efficiency of ion transmission from atmosphere to vacuum through stainless steel electrodes that contain slowly divergent conical duct (ConDuct) channels can be close to 100%. Here, we explore the properties of 2.5 cm long electrodes with angles of divergence of 0°, 1°, 2°, 3°, 5°, 8°, 13°, and 21°, respectively. The ion transmission efficiency was observed to jump from 10–20% for the 0° (straight) channels to 90–95% for channels with an angle of divergence as small as 1°. Furthermore, the 2–3° ConDuct electrodes produced extraordinarily low divergence ion beams that propagated in a laser-like fashion over long distances in vacuum. To take advantage of these newly discovered properties, we constructed a novel atmosphere-to-vacuum ion interface utilizing a 2° ConDuct as an inlet electrode and compared its ion transmission efficiency with that of the interface used in the commercial (Thermo) Velos Orbitrap and Q Exactive mass spectrometers. We observed that the ConDuct interface transmitted up to 17 times more ions than the commercial reference interface and also yielded improved signal-to-noise mass spectra of peptides. We infer from these results that the performance of many current atmosphere-tovacuum interfaces utilizing metal capillaries can be substantially improved by replacing them with 1° or 2° metal ConDuct electrodes, which should preserve the convenience of supplying ion desolvation energy by heating the electrode while greatly increasing the efficiency of ion transmission into the mass spectrometer. PMID:25667060

Optimizing Electrospray Interfaces Using Slowly Diverging Conical Duct (ConDuct) Electrodes

NASA Astrophysics Data System (ADS)

Krutchinsky, Andrew N.; Padovan, Júlio C.; Cohen, Herbert; Chait, Brian T.

2015-04-01

We demonstrate that the efficiency of ion transmission from atmosphere to vacuum through stainless steel electrodes that contain slowly divergent conical duct (ConDuct) channels can be close to 100%. Here, we explore the properties of 2.5-cm-long electrodes with angles of divergence of 0°, 1°, 2°, 3°, 5°, 8°, 13°, and 21°, respectively. The ion transmission efficiency was observed to jump from 10-20% for the 0° (straight) channels to 90-95% for channels with an angle of divergence as small as 1°. Furthermore, the 2-3° ConDuct electrodes produced extraordinarily low divergence ion beams that propagated in a laser-like fashion over long distances in vacuum. To take advantage of these newly discovered properties, we constructed a novel atmosphere-to-vacuum ion interface utilizing a 2° ConDuct as an inlet electrode and compared its ion transmission efficiency with that of the interface used in the commercial (Thermo Fisher Scientific, San Jose, CA, USA) Velos Orbitrap and Q Exactive mass spectrometers. We observed that the ConDuct interface transmitted up to 17 times more ions than the commercial reference interface and also yielded improved signal-to-noise mass spectra of peptides. We infer from these results that the performance of many current atmosphere-to-vacuum interfaces utilizing metal capillaries can be substantially improved by replacing them with 1° or 2° metal ConDuct electrodes, which should preserve the convenience of supplying ion desolvation energy by heating the electrode while greatly increasing the efficiency of ion transmission into the mass spectrometer.

SeleCon: Scalable IoT Device Selection and Control Using Hand Gestures.

PubMed

Alanwar, Amr; Alzantot, Moustafa; Ho, Bo-Jhang; Martin, Paul; Srivastava, Mani

2017-04-01

Although different interaction modalities have been proposed in the field of human-computer interface (HCI), only a few of these techniques could reach the end users because of scalability and usability issues. Given the popularity and the growing number of IoT devices, selecting one out of many devices becomes a hurdle in a typical smarthome environment. Therefore, an easy-to-learn, scalable, and non-intrusive interaction modality has to be explored. In this paper, we propose a pointing approach to interact with devices, as pointing is arguably a natural way for device selection. We introduce SeleCon for device selection and control which uses an ultra-wideband (UWB) equipped smartwatch. To interact with a device in our system, people can point to the device to select it then draw a hand gesture in the air to specify a control action. To this end, SeleCon employs inertial sensors for pointing gesture detection and a UWB transceiver for identifying the selected device from ranging measurements. Furthermore, SeleCon supports an alphabet of gestures that can be used for controlling the selected devices. We performed our experiment in a 9 m -by-10 m lab space with eight deployed devices. The results demonstrate that SeleCon can achieve 84.5% accuracy for device selection and 97% accuracy for hand gesture recognition. We also show that SeleCon is power efficient to sustain daily use by turning off the UWB transceiver, when a user's wrist is stationary.

Propiedades biomecánicas de la membrana limitante interna tras recibir tratamiento intravítreo con ocriplasmina.

PubMed

Vielmuth, Franziska; Schumann, Ricarda G; Spindler, Volker; Wolf, Armin; Scheler, Renate; Mayer, Wolfgang J; Henrich, Paul B; Haritoglou, Christos

2017-01-01

Objetivo: Evaluar la rigidez de la membrana limitante interna (MLI) humana y evaluar los posibles cambios de las propiedades mecánicas tras administrar una inyección intravítrea de ocriplasmina para tratar la tracción vitreomacular. Métodos: Este estudio se compone de una serie de casos intervencionales y comparativos de 12 muestras de MLI extraídas mediante cirugía y obtenidas de forma consecutiva de 9 ojos de 9 pacientes después de someterse sin éxito a vitreólisis farmacológica con ocriplasmina. Durante el mismo periodo de tiempo, 16 muestras de otros 13 ojos sin tratamiento con ocriplasmina se obtuvieron mediante vitrectomía y sirvieron como controles. Todos los pacientes presentaron agujeros maculares o tracción vitreomacular y se sometieron a vitrectomía con disección de la MLI tanto con tinción con azul brillante (AB) como sin ella. Todas las muestras se analizaron con un microscopio de fuerza atómica con imágenes de las regiones de 25 × 25 μm. En todas las muestras, se analizaron tanto la parte de la retina como la del vítreo de la MLI. Resultados: La microscopia de fuerza atómica no reveló diferencias significativas en cuanto a elasticidad de las muestras de MLI extraídas de ojos con o sin tratamiento con ocriplasmina. Las áreas onduladas de la parte de la retina presentaron una mayor rigidez que la parte del vítreo de la MLI. La cartografía topográfica tanto de la parte del vítreo como de la retina de la MLI no mostró ninguna alteración aparente de la morfología en ojos tratados con ocriplasmina en comparación con los ojos no tratados. La tinción con azul brillante conllevó un aumento de la rigidez tisular. Conclusiones: Las inyecciones intravítreas de ocriplasmina no varían las propiedades biomecánicas de la MLI humana. No existen pruebas de un posible efecto enzimático que interfiera con la rigidez de esta membrana basal. © 2017 S. Karger AG, Basel.

B cells as accessory cells in a Con A response of a T cell clone.

PubMed

Takeuchi, M; Kakiuchi, T; Taira, S; Nariuchi, H

1987-12-01

Accessory cell (AC) function of B cells was examined in Con A response of a cloned T cell line, 22-9D, which is Thy 1+,L3T4+,Lyt2-,H-2KbDb+ and I-Ab-.22-9D cells produced IL 2 in the presence of Con A without participation of AC. For the initiation of a proliferative response to Con A, the addition of spleen cells or spleen adherent cells was required. B cells as AC were unable to induce the proliferative response. In the presence of culture supernatant of spleen cells stimulated with Con A (CAS), 22-9D cells showed proliferative response to Con A with B cell AC. The response was inhibited by a relevant monoclonal anti-I-A antibody. Although irradiated spleen cells as AC induced IL 2 receptor expression of 22-9D cells in the presence of Con A, B cells were shown to require the addition of unknown factor(s) in CAS, which was suggested to be different from IL 1, IL 2, IL 3, or IFN-gamma, for the induction of the receptor expression on 22-9D cells.

Wildland Fire Induced Heating of Dome 375 Perma-Con®

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flores, Eugene Michael

AET-1 was tasked by ADEM with determining the temperature rise in the drum contents of drums stored in the Dome 375 Perma-Con® at TA-54 given a wildland fire. The wildland fire causes radiative and convective heating on the Perma-Con® exterior. The wildland fire time histories for the radiative and convective heating environment were provided to AET-1 by EES-16. If the calculated temperature rise results in a drum content temperature over 40 °C, then ADEM desires a design solution to ensure the peak temperature remains below 40 °C. An axi-symmetric FE simulation was completed to determine the peak temperature of themore » contents of a drum stored in the Dome 375 Perma-Con® during a wildland fire event. Three wildland fire time histories for the radiative and convective heat transfer were provided by EES-16 and were inputs for the FE simulation. The maximum drum content temperature reached was found to be 110 °C while using inputs from the SiteG_2ms_4ign_wind_from_west.xlsx time history input and not including the SWB in the model. Including the SWB in the results in a peak drum content temperature of 61 °C for the SiteG_2ms_4ign_wind_from_west.xlsx inputs. EES-16 decided that by using fuel mitigation efforts, such as mowing the grass and shrubs near the Perma-Con® they could reduce the shrub/grass fuel loading near the Perma-Con® from 1.46 kg/m 2 to 0.146 kg/m 2 and by using a less conservative fuel loading for the debris field inside the Dome 375 perimeter, reducing it from 0.58 kg/m2 to 0.058 kg/m 2 in their model. They also greatly increased the resolution of their radiation model and increased the accuracy of their model’s required convergence value. Using this refined input the maximum drum content temperature was found to be 28 °C with no SWB present in the model. Additionally, this refined input model was modified to include worst case emissivity values for the concrete, drum and Perma-Con® interior, along with adding a 91 second long

There Is No Correlation Between Erectile Dysfunction and Dose to Penile Bulb and Neurovascular Bundles Following Real-Time Low-Dose-Rate Prostate Brachytherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Solan, Amy N.; Cesaretti, Jamie A.; Stone, Nelson N.

2009-04-01

Purpose: We evaluated the relationship between the onset of erectile dysfunction and dose to the penile bulb and neurovascular bundles (NVBs) after real-time ultrasound-guided prostate brachytherapy. Methods and Materials: One hundred forty-seven patients who underwent prostate brachytherapy met the following eligibility criteria: (1) treatment with {sup 125}I brachytherapy to a prescribed dose of 160 Gy with or without hormones without supplemental external beam radiation therapy, (2) identification as potent before the time of implantation based on a score of 2 or higher on the physician-assigned Mount Sinai Erectile Function Score and a score of 16 or higher on the abbreviatedmore » International Index of Erectile Function patient assessment, and (3) minimum follow-up of 12 months. Median follow-up was 25.7 months (range, 12-47 months). Results: The 3-year actuarial rate of impotence was 23% (34 of 147 patients). An additional 43% of potent patients (49 of 113 patients) were using a potency aid at last follow-up. The penile bulb volume receiving 100% of the prescription dose (V{sub 100}) ranged from 0-0.05 cc (median, 0 cc), with a dose to the hottest 5% (D{sub 5}) range of 12.5-97.9 Gy (median, 40.8 Gy). There was no correlation between penile bulb D{sub 5} or V{sub 100} and postimplantation impotency on actuarial analysis. For the combined right and left NVB structures, V{sub 100} range was 0.3-5.1 cc (median, 1.8 cc), and V{sub 150} range was 0-1.5 cc (median, 0.31 cc). There was no association between NVB V{sub 100} or V{sub 150} and postimplantation impotency on actuarial analysis. Conclusion: Penile bulb doses are low after real-time ultrasound-guided prostate brachytherapy. We found no correlation between dose to either the penile bulb or NVBs and the development of postimplantation impotency.« less

Cálculos ab initio con correlación electrónica

NASA Astrophysics Data System (ADS)

Merchán Bonete, M.

Estamos entrando en una era donde la ortogonalidad entre las investigaciones de carácter experimental y de naturaleza teórica se irá difuminando progresivamente y la problemática a resolver quedará en escena como el único actor principal de la obra. Como premisa para una cooperación teórico-experimental de igual a igual, la metodología químico-cuántica utilizada debe ser capaz de ofrecer resultados de carácter predictivo. Sin duda, esta madurez en la metodología químico-cuántica ya la hemos alcanzado hace algunos años, tal y como muestra entre otras muchas, la labor que nuestro grupo ha realizado en el transcurso de la última década, dentro del campo de la Espectroscopía Teórica. Los estudios realizados comprenden una amplia gama de sistemas, variando tanto en tamaño como en complejidad, abordando problemáticas espectroscópicas consideradas tradicionalmente como especialmente controvertidas. Nuestra contribución científica más relevante reside en el carácter cuantitativo de las asignaciones espectroscópicas que hemos propuesto en base a resultados ab initio. Recordemos que en los años noventa los resultados ab initio solían presentar para las energías de excitación de sistemas de tamaño molecular moderado, como el benceno, errores de más de 1 eV. En comparación con el éxito relativo de los métodos semiempíricos, la frustración de la metodología ab initio quedaba todavía más patente. Los estudios que hemos presentado representan una comprensión profunda de los espectros electrónicos en sistemas orgánicos claves, mostrando el camino a seguir para obtener asignaciones espectroscópicas precisas (entre 0.1-0.2 eV). La naturaleza del método CASPT2 junto al diseño de estrategias computacionales nos ha permitido alcanzar el carácter cuantitativo con el que se caracterizan nuestras contribuciones[1,2]. Por todo ello, algunos de los trabajos publicados se consideran clásicos dentro del campo, pues en cierto modo definen el

La salud en personas con discapacidad intelectual en España: estudio europeo POMONA-II

PubMed Central

Martínez-Leal, Rafael; Salvador-Carulla, Luis; Gutiérrez-Colosía, Mencía Ruiz; Nadal, Margarida; Novell-Alsina, Ramón; Martorell, Almudena; González-Gordón, Rodrigo G.; Mérida-Gutiérrez, M. Reyes; Ángel, Silvia; Milagrosa-Tejonero, Luisa; Rodríguez, Alicia; García-Gutiérrez, Juan C.; Pérez-Vicente, Amado; García-Ibáñez, José; Aguilera-Inés, Francisco

2011-01-01

Introducción Estudios internacionales demuestran que existe un patrón diferenciado de salud y una disparidad en la atención sanitaria entre personas con discapacidad intelectual (DI) y población general. Objetivo Obtener datos sobre el estado de salud de las personas con DI y compararlos con datos de población general. Pacientes y métodos Se utilizó el conjunto de indicadores de salud P15 en una muestra de 111 sujetos con DI. Los datos de salud encontrados se compararon según el tipo de residencia de los sujetos y se utilizó la Encuesta Nacional de Salud 2006 para comparar estos datos con los de la población general. Resultados La muestra con DI presentó 25 veces más casos de epilepsia y el doble de obesidad. Un 20% presentó dolor bucal, y existió una alta presencia de problemas sensoriales, de movilidad y psicosis. Sin embargo, encontramos una baja presencia de patologías como la diabetes, la hipertensión, la osteoartritis y la osteoporosis. También presentaron una menor participación en programas de prevención y promoción de la salud, un mayor número de ingresos hospitalarios y un uso menor de los servicios de urgencia. Conclusiones El patrón de salud de las personas con DI difiere del de la población general, y éstas realizan un uso distinto de los servicios sanitarios. Es importante el desarrollo de programas de promoción de salud y de formación profesional específicamente diseñados para la atención de personas con DI, así como la implementación de encuestas de salud que incluyan datos sobre esta población. PMID:21948011

Energy Star program benefits Con Edison

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

Impressed with savings in energy costs achieved after upgrading the lighting and air conditioning systems at its Manhattan headquarters, Home Box Office (HBO) wanted to do more, James Flock, vice president for computer and office systems, contacted Con Edison Co. of New York in March 1991 to determine what the company could do to save money by reducing energy consumed by personal computers. Arthur Kressner, Con Edison Research and Development manager contacted industry organizations and manufacturers for advice, but was told only to shut off computers at night and on weekends. Kressner arranged a series of meetings with IBM andmore » the Electric Power Research Institute (EPRI) to discuss the issue, then approached the U.S. Environmental Protection Agency (EPA), which was designing a program to promote the introduction and use of energy-efficient office equipment. In 1992, the EPA announced the Energy Star program for PCs, enabling manufacturers to display the Energy Star logo on machines meeting program criteria, including the ability to enter a sleep mode in which neither the computer nor monitor consume more than 30 W or electricity. Industry experts estimate national energy consumption by office equipment could double by the year 2000, but Energy Star equipment is expected to improve efficiency and help maintain electric loads.« less

SeleCon: Scalable IoT Device Selection and Control Using Hand Gestures

PubMed Central

Alanwar, Amr; Alzantot, Moustafa; Ho, Bo-Jhang; Martin, Paul; Srivastava, Mani

2018-01-01

Although different interaction modalities have been proposed in the field of human-computer interface (HCI), only a few of these techniques could reach the end users because of scalability and usability issues. Given the popularity and the growing number of IoT devices, selecting one out of many devices becomes a hurdle in a typical smarthome environment. Therefore, an easy-to-learn, scalable, and non-intrusive interaction modality has to be explored. In this paper, we propose a pointing approach to interact with devices, as pointing is arguably a natural way for device selection. We introduce SeleCon for device selection and control which uses an ultra-wideband (UWB) equipped smartwatch. To interact with a device in our system, people can point to the device to select it then draw a hand gesture in the air to specify a control action. To this end, SeleCon employs inertial sensors for pointing gesture detection and a UWB transceiver for identifying the selected device from ranging measurements. Furthermore, SeleCon supports an alphabet of gestures that can be used for controlling the selected devices. We performed our experiment in a 9m-by-10m lab space with eight deployed devices. The results demonstrate that SeleCon can achieve 84.5% accuracy for device selection and 97% accuracy for hand gesture recognition. We also show that SeleCon is power efficient to sustain daily use by turning off the UWB transceiver, when a user’s wrist is stationary. PMID:29683151

Sport Concussion Management Using Facebook: A Feasibility Study of an Innovative Adjunct "iCon".

PubMed

Ahmed, Osman Hassan; Schneiders, Anthony G; McCrory, Paul R; Sullivan, S John

2017-04-01

  Sport concussion is currently the focus of much international attention. Innovative methods to assist athletic trainers in facilitating management after this injury need to be investigated.   To investigate the feasibility of using a Facebook concussion-management program termed iCon (interactive concussion management) to facilitate the safe return to play (RTP) of young persons after sport concussion.   Observational study.   Facebook group containing interactive elements, with moderation and support from trained health care professionals.   Eleven participants (n = 9 men, n = 2 women; range, 18 to 28 years old) completed the study.   The study was conducted over a 3-month period, with participant questionnaires administered preintervention and postintervention. The primary focus was on the qualitative experiences of the participants and the effect of iCon on their RTP. Usage data were also collected.   At the completion of the study, all participants (100%) stated that they would recommend an intervention such as iCon to others. Their supporting quotes all indicated that iCon has the potential to improve the management of concussion among this cohort. Most participants (n = 9, 82%) stated they were better informed with regard to their RTP due to participating in iCon.   This interactive adjunct to traditional concussion management was appreciated among this participant group, which indicates the feasibility of a future, larger study of iCon. Athletic trainers should consider the role that multimedia technologies may play in assisting with the management of sport concussion.

Influence of protic ionic liquids on the structure and stability of succinylated Con A.

PubMed

Attri, Pankaj; Venkatesu, Pannuru

2012-01-01

We report the synthesis of a series of ionic liquids (ILs) from various ions having different kosmotropicity including dihydrogen phosphate (H(2)PO(4)(-)), hydrogen sulfate (HSO(4)(-)) and acetate (CH(3)COO(-)) as anions and chaotropic cation such as trialkylammonium cation. To characterize the biomolecular interactions of ILs with protein, we have explored the stability of succinylated Con A (S Con A) in the presence of these aqueous ILs, which are varied combinations of kosmotropic anion with chaotropic cation such as triethylammonium dihydrogen phosphate [(CH(3)CH(2))(3)NH][H(2)PO(4)] (TEAP), trimethylammonium acetate [(CH(3))(3)NH][CH(3)COO] (TMAA), trimethylammonium dihydrogen phosphate [(CH(3))(3)NH][H(2)PO(4)] (TMAP) and trimethylammonium hydrogen sulfate [(CH(3))(3)NH][HSO(4)] (TMAS). Circular dichroism (CD) and fluorescence experiments have been used to characterize the stability of S Con A by ILs. Our data distinctly demonstrate that the long alkyl chain IL TEAP is a strong stabilizer for S Con A. Further, our experimental results reveal that TEAP is an effective refolding enhancer for S Con A from a thermally denatured protein structure. Copyright © 2012 Elsevier B.V. All rights reserved.

Apoyo a Estudios Geodinamicos con GPS en Guatemala

NASA Astrophysics Data System (ADS)

Robles, V. R.

2013-05-01

El Instituto Geografico Nacional de Guatemala implemento 17 estaciones GNSS en el año 2009, como un proyecto de credito mixto de donacion de equipamiento del Gobierno de Suiza, el cual, este equipamiento de estaciones CORS GNSS es un sistema de recepción y transmisión de datos crudos GPS RInex que utiliza la tecnologia Spider Web de Leica, asi mismo este sistema esta sirviendo para el espablecimiento de un marco geodesico nacional de coordenadas geodesicas oficiales, el cual se calculan u obtienen las velocidades en tiempos temporales programados de las 17 Estaciones CORS. La infraestructura del marco geodesico de Guatemala esta sirviendo de base para las aplicaciones de estudios geodinamicos como el monitoreo de del desplazamiento de las placas tectonicas por medio de un estudio que se inicio en el año de 1999, llamado medicion con GPS el sistema de Fallas de los rios Polochic Motagua de Guatemala, tambien para un estudio que se implemento para deformación de corteza terrestre local en un Volcan Activo de Guatemala llamado Pacaya. Para el estudio de medicion con GPS en el sistema de falla de los Rios del polochic Motagua se implementaron 16 puntos para medir con GPS de dos frecuencias en el año de 1999, el cual, tres puntos son estaciones geodesicas CORS IGS llamados GUAT, ELEN y HUEH, despues en el año de 2003 se hizo otra medicion en un total de 20 puntos, que permitió calcular las velocidades de desplazamieinto de los puntos en mención, usando como referencia el modelo NUVEL 1A de DeMets de la placa de Norteamerica. Este estudio fue en cooperación internacional por la universidad de Nice de Francia y el IGNde Francia. Para el estudio del monitoreo con GPS del volcan activo de Guatemala, se implementaron cuatro puntos al rededor del volcan, el cual, se realizan cuatro mediciones al año, que permiten determinar axialmente la distancias entre los puntos, y rebisar estadisticamente cual es el comportamiento de las distancias en funcion del tiempo, si

Physician training protocol within the WEB Intrasaccular Therapy (WEB-IT) study.

PubMed

Arthur, Adam; Hoit, Daniel; Coon, Alexander; Delgado Almandoz, Josser E; Elijovich, Lucas; Cekirge, Saruhan; Fiorella, David

2018-05-01

The WEB Intra-saccular Therapy (WEB-IT) trial is an investigational device exemption study to demonstrate the safety and effectiveness of the WEB device for the treatment of wide-neck bifurcation aneurysms. The neurovascular replicator (Vascular Simulations, Stony Brook, New York, USA) creates a physical environment that replicates patient-specific neurovascular anatomy and hemodynamic physiology, and allows devices to be implanted under fluoroscopic guidance. To report the results of a unique neurovascular replicator-based training program, which was incorporated into the WEB-IT study to optimize technical performance and patient safety. US investigators participated in a new training program that incorporated full surgical rehearsals on a neurovascular replicator. No roll-in cases were permitted within the trial. Custom replicas of patient-specific neurovascular anatomy were created for the initial cases treated at each center, as well as for cases expected to be challenging. On-site surgical rehearsals were performed before these procedures. A total of 48 participating investigators at 25 US centers trained using the replicator. Sessions included centralized introductory training, on-site training, and patient-specific full surgical rehearsal. Fluoroscopy and procedure times in the WEB-IT study were not significantly different from those seen in two European trials where participating physicians had significant WEB procedure experience before study initiation. A new program of neurovascular-replicator-based physician training was employed within the WEB-IT study. This represents a new methodology for education and training that may be an effective means to optimize technical success and patient safety during the introduction of a new technology. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Venous compressions of the nerves in the lower limbs.

PubMed

Artico, M; Stevanato, G; Ionta, B; Cesaroni, A; Bianchi, E; Morselli, C; Grippaudo, F R

2012-06-01

The lower limbs are frequently involved in neurovascular compression syndromes, owing to their anatomical, vascular and muscular characteristics and to the orthostatic position. These syndromes were identified by exclusion, using neuroimaging techniques and treated by microsurgical techniques. Eight patients with a neurovascular compression syndrome due to venous vascular lesions in the lower limbs (popliteal fossa, proximal and medial third of the inferior limb, tarsal tunnel) were selected. The symptomatology was characterized by pain, Tinel's sign, hyperalgesia, allodynia, numbness along the nerve course and foot weakness: all were exacerbated by the standing position, thus suggesting a neurovascular compression syndrome. Diagnostic tools comprised Doppler ultrasonography, Electromyography, CT 3D and MRI. Treatment consisted of microsurgery with neurovascular dissection. Following surgical treatment, rapid pain relief and a partial recovery of neurological deficits (including the ability to walk) was observed within 8-10 months. An early diagnosis of NCS using various neuroimaging techniques and prompt treatment may improve the response to surgical therapy. The aim of the case studies described is to improve understanding of these pathologies thus enabling correct clinical decisions.

Patterns of relapse in primary central nervous system lymphoma: inferences regarding the role of the neuro-vascular unit and monoclonal antibodies in treating occult CNS disease.

PubMed

Ambady, Prakash; Fu, Rongwei; Netto, Joao Prola; Kersch, Cymon; Firkins, Jenny; Doolittle, Nancy D; Neuwelt, Edward A

2017-06-02

The radiologic features and patterns of primary central nervous system lymphoma (PCNSL) at initial presentation are well described. High response rates can be achieved with first-line high-dose methotrexate (HD-MTX) based regimens, yet many relapse within 2 years of diagnosis. We describe the pattern of relapse and review the potential mechanisms involved in relapse. We identified 78 consecutive patients who attained complete radiographic response (CR) during or after first-line treatment for newly diagnosed PCNSL (CD20+, diffuse large B cell type). Patients were treated with HD-MTX based regimen in conjunction with blood-brain barrier disruption (HD-MTX/BBBD); 44 subsequently relapsed. Images and medical records of these 44 consecutive patients were retrospectively reviewed. The anatomical location of enhancing lesions at initial diagnosis and at the time of relapse were identified and compared. 37/44 patients fulfilled inclusion criteria and had new measureable enhancing lesions at relapse; the pattern and location of relapse of these 37 patients were identified. At relapse, the new enhancement was at a spatially distinct site in 30 of 37 patients. Local relapse was found only in seven patients. Unlike gliomas, the majority of PCNSL had radiographic relapse at spatially distinct anatomical locations within the brain behind a previously intact neurovascular unit (NVU), and in few cases outside, the central nervous system (CNS). This may suggest either (1) reactivation of occult reservoirs behind an intact NVU in the CNS (or ocular) or (2) seeding from bone marrow or other extra CNS sites. Recognizing patterns of relapse is key for early detection and may provide insight into potential mechanisms of relapse as well as help develop strategies to extend duration of complete response.

A Review of Staphylococcal Cassette Chromosome mec (SCCmec) Types in Coagulase-Negative Staphylococci (CoNS) Species.

PubMed

Saber, Huda; Jasni, Azmiza Syawani; Jamaluddin, Tengku Zetty Maztura Tengku; Ibrahim, Rosni

2017-10-01

Coagulase-negative staphylococci (CoNS) are considered low pathogenic organisms. However, they are progressively causing more serious infections with time because they have adapted well to various antibiotics owing to their ability to form biofilms. Few studies have been conducted on CoNS in both, hospital and community-acquired settings, especially in Malaysia. Thus, it is important to study their species and gene distributions. A mobile genetic element, staphylococcal cassette chromosome mec (SCC mec ), plays an important role in staphylococci pathogenesis. Among CoNS, SCC mec has been studied less frequently than Staphylococcus aureus (coagulase-positive staphylococci). A recent study (8) conducted in Malaysia successfully detected SCC mec type I to VIII as well as several new combination patterns in CoNS species, particularly Staphylococcus epidermidis . However, data are still limited, and further research is warranted. This paper provides a review on SCC mec types among CoNS species.

Connected vehicle pilot deployment program phase 1, concept of operations (ConOps) – Tampa (THEA).

DOT National Transportation Integrated Search

2016-02-01

This document describes the Concept of Operations (ConOps) for the Tampa Hillsborough Expressway Authority (THEA) Connected Vehicle (CV) Pilot Deployment. This ConOps describes the current state of operations, establishes the reasons for change, and ...

Connected vehicle pilot deployment program phase 1, concept of operations (ConOps) - New York City.

DOT National Transportation Integrated Search

2016-04-08

This document describes the Concept of Operations (ConOps) for the New York City Department of Transportation (NYC) Connected Vehicle Pilot Deployment (CVPD) Project. This ConOps describes the current state of operations, establishes the reasons for ...

Inclusion: The Pros and Cons--A Critical Review

ERIC Educational Resources Information Center

Savich, Carl

2008-01-01

The purpose of this paper was to review, analyze, and critique the pros and cons, the advantages and disadvantages, of inclusion. The methodology consisted in analyzing and comparing research findings on the benefits and costs of inclusion. Federal legislation and regulations on inclusion were examined, analyzed, and discussed. The results showed…

Precisión de las velocidades radiales obtenidas con el REOSC

NASA Astrophysics Data System (ADS)

González, J. F.; Lapasset, E.

Complementando una línea de trabajo iniciada con anterioridad discutimos la estabilidad del espectrógrafo REOSC de CASLEO en DC para la medición de velocidades radiales en base al análisis de observaciones realizadas en enero y abril de 1997. En esas oportunidades obtuvimos 26 espectros de estrellas patrones y 27 espectros de 3 estrellas usadas como estrellas de referencia en nuestro programa de cúmulos abiertos. Además tomamos 26 espectros de crepúsculo con el telescopio en posiciones cubriendo el rango H=-4,+4 y δ =-90,+30. Mediante correlaciones cruzadas derivamos la velocidad de 19 órdenes en cada uno de estos espectros. En base a un análisis estadístico de los datos obtenidos discutimos la contribución de los distintos factores que afectan a la dispersión de lectura observada. En particular, la flexión del instrumento no introduciría errores significativos cuando se observa con masas de aire menores que 2.0. La dispersión de los valores de velocidad medidos para espectros de alta relación S/N de una misma estrella resultó del orden de 0.5 km/s. La comparación con los valores de velocidad publicados por distintos autores para las estrellas patrones no permite distinguir ninguna diferencia sistemática apreciable de las velocidades de CASLEO, siendo la media cuadrática de los residuos del orden de 1.0 km/s.

Tailoring a ConOps for NASA LSP Integrated Operations

NASA Technical Reports Server (NTRS)

Owens, Skip Clark V., III

2017-01-01

An integral part of the Systems Engineering process is the creation of a Concept of Operations (ConOps) for a given system, with the ConOps initially established early in the system design process and evolved as the system definition and design matures. As Integration Engineers in NASA's Launch Services Program (LSP) at Kennedy Space Center (KSC), our job is to manage the interface requirements for all the robotic space missions that come to our Program for a Launch Service. LSP procures and manages a launch service from one of our many commercial Launch Vehicle Contractors (LVCs) and these commercial companies are then responsible for developing the Interface Control Document (ICD), the verification of the requirements in that document, and all the services pertaining to integrating the spacecraft and launching it into orbit. However, one of the systems engineering tools that have not been employed within LSP to date is a Concept of Operations. The goal of this paper is to research the format and content that goes into these various aerospace industry ConOps and tailor the format and content into template form, so the template may be used as an engineering tool for spacecraft integration with future LSP procured launch services. This tailoring effort was performed as the authors final Masters Project in the Spring of 2016 for the Stevens Institute of Technology and modified for publication with INCOSE (Owens, 2016).

Canceling Some d-CON Mouse and Rat Control Products

EPA Pesticide Factsheets

EPA has reached agreement with the manufacturer, to cancel 12 d-CON products that do not meet our testing protocols that better protect children, pets and non-target wildlife from accidental exposure to the pesticide. These products will be phased out.

The ConSurf-DB: pre-calculated evolutionary conservation profiles of protein structures.

PubMed

Goldenberg, Ofir; Erez, Elana; Nimrod, Guy; Ben-Tal, Nir

2009-01-01

ConSurf-DB is a repository for evolutionary conservation analysis of the proteins of known structures in the Protein Data Bank (PDB). Sequence homologues of each of the PDB entries were collected and aligned using standard methods. The evolutionary conservation of each amino acid position in the alignment was calculated using the Rate4Site algorithm, implemented in the ConSurf web server. The algorithm takes into account the phylogenetic relations between the aligned proteins and the stochastic nature of the evolutionary process explicitly. Rate4Site assigns a conservation level for each position in the multiple sequence alignment using an empirical Bayesian inference. Visual inspection of the conservation patterns on the 3D structure often enables the identification of key residues that comprise the functionally important regions of the protein. The repository is updated with the latest PDB entries on a monthly basis and will be rebuilt annually. ConSurf-DB is available online at http://consurfdb.tau.ac.il/

The ConSurf-DB: pre-calculated evolutionary conservation profiles of protein structures

PubMed Central

Goldenberg, Ofir; Erez, Elana; Nimrod, Guy; Ben-Tal, Nir

2009-01-01

ConSurf-DB is a repository for evolutionary conservation analysis of the proteins of known structures in the Protein Data Bank (PDB). Sequence homologues of each of the PDB entries were collected and aligned using standard methods. The evolutionary conservation of each amino acid position in the alignment was calculated using the Rate4Site algorithm, implemented in the ConSurf web server. The algorithm takes into account the phylogenetic relations between the aligned proteins and the stochastic nature of the evolutionary process explicitly. Rate4Site assigns a conservation level for each position in the multiple sequence alignment using an empirical Bayesian inference. Visual inspection of the conservation patterns on the 3D structure often enables the identification of key residues that comprise the functionally important regions of the protein. The repository is updated with the latest PDB entries on a monthly basis and will be rebuilt annually. ConSurf-DB is available online at http://consurfdb.tau.ac.il/ PMID:18971256

A Randomized Phase 2 Study of Long-Acting TransCon GH vs Daily GH in Childhood GH Deficiency.

PubMed

Chatelain, Pierre; Malievskiy, Oleg; Radziuk, Klaudziya; Senatorova, Ganna; Abdou, Magdy O; Vlachopapadopoulou, Elpis; Skorodok, Yulia; Peterkova, Valentina; Leff, Jonathan A; Beckert, Michael

2017-05-01

TransCon Growth Hormone (GH) (Ascendis Pharma) is a long-acting recombinant sustained-release human GH prodrug in development for children with GH deficiency (GHD). To compare the pharmacokinetics, pharmacodynamics, safety, and efficacy of weekly TransCon GH to that of daily GH in prepubertal children with GHD. Randomized, open-label, active-controlled study of three doses of weekly TransCon GH versus daily Genotropin (Pfizer). Thirty-eight centers in 14 European countries and Egypt. Prepubertal male and female treatment-naïve children with GHD (n = 53). Subjects received one of three TransCon GH doses (0.14, 0.21, or 0.30 mg GH/kg/wk) or Genotropin 0.03 mg GH/kg/d for 26 weeks. GH and insulinlike growth factor-1 (IGF-1) levels, growth, adverse events, and immunogenicity. Both GH maximum concentration and area under the curve were similar following TransCon GH or Genotropin administration at comparable doses. A dose response was observed, with IGF-1 standard deviation scores increasing into the normal range for all three TransCon GH doses. Annualized mean height velocity for the three TransCon GH doses ranged from 11.9 cm to 13.9 cm, which was not statistically different from 11.6 cm for Genotropin. Adverse events were mild to moderate, and most were unrelated to the study drug. Injection site tolerance was good. One TransCon GH subject developed a low-titer, nonneutralizing antibody response to GH. The results suggest that long-acting TransCon GH is comparable to daily Genotropin for GH (pharmacokinetics) and IGF-1 (pharmacodynamics) levels, safety, and efficacy and support advancement into phase 3 development. Copyright © 2017 Endocrine Society

Teaching after Retirement: The Pros and the Cons

ERIC Educational Resources Information Center

Sommer, Robert

2014-01-01

Having enjoyed teaching during my active career, I continued to teach summer school following retirement. Self-observed sensory and cognitive impairments, although not mentioned by students in their evaluations, induced me to consider the pros and cons of continuing to teach. My hope is that this list of benefits and problems will be of assistance…

40 CFR 180.1213 - Coniothyrium minitans strain CON/M/91-08; exemption from the requirement of a tolerance.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Coniothyrium minitans strain CON/M/91... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1213 Coniothyrium minitans strain CON/M... tolerance is established for residues of the microbial pesticide Coniothyrium minitans strain CON/M/91-08...

40 CFR 180.1213 - Coniothyrium minitans strain CON/M/91-08; exemption from the requirement of a tolerance.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Coniothyrium minitans strain CON/M/91... PESTICIDE CHEMICAL RESIDUES IN FOOD Exemptions From Tolerances § 180.1213 Coniothyrium minitans strain CON/M... tolerance is established for residues of the microbial pesticide Coniothyrium minitans strain CON/M/91-08...

Distal Extension of the Direct Anterior Approach to the Hip: A Cadaveric Feasibility Study.

PubMed

Ghijselings, Stijn G M; Driesen, Ronald; Simon, Jean-Pierre; Corten, Kristoff

2017-01-01

The direct anterior approach (DAA) is becoming more popular as the standard surgical approach for primary total hip arthroplasty. However, femoral complications of up to 2.8% have been reported. Therefore, it is important for surgeons to understand the periarticular neurovascular anatomy in order to safely deal with intraoperative complications. Anatomic dissections were performed on 20 cadaveric hips. The neurovascular structures anterior to the femur and distal to the intertrochanteric line were dissected and its position was described in relation to anatomic landmarks easily identified through the DAA: anterior superior iliac spine (ASIS), the insertion of the gluteus minimus (GM), and the lesser trochanter (LT). Two clearly distinguishable neurovascular bundles running to the vastus lateralis were seen in 17 of 20 specimens. The average distances to the landmarks were as follows: ASIS-1st bundle = 12.3 cm (range, 9.7-14.5); GM-1st bundle = 3.2 cm (range, 2.2-4); LT-1st bundle = 1.6 cm (range, 0.7-2.8); 1st bundle-2nd bundle = 3.3 cm (range, 1.8-6.1). A consistent pattern of 2 clearly distinguishable neurovascular bundles was seen in 85% of the specimens. Knowledge of the position of these neurovascular bundles in relation to the anatomic landmarks makes distal femoral extension of the DAA feasible. Further clinical studies are needed to confirm the safety of the extensile anterior approach. Copyright © 2016 Elsevier Inc. All rights reserved.

The estimation of hemodynamic signals measured by fNIRS response to cold pressor test

NASA Astrophysics Data System (ADS)

Ansari, M. A.; Fazliazar, E.

2018-04-01

The estimation of cerebral hemodynamic signals has an important role for monitoring the stage of neurological diseases. Functional Near-Infrared Spectroscopy (fNIRS) can be used for monitoring of brain activities. fNIRS utilizes light in the near-infrared spectrum (650-1000 nm) to study the response of the brain vasculature to the changes in neural activities, called neurovascular coupling, within the cortex when cognitive activation occurs. The neurovascular coupling may be disrupted in the brain pathological condition. Therefore, we can also use fNIRS to diagnosis brain pathological conditions or to monitor the efficacy of related treatments. The Cold pressor test (CPT), followed by immersion of dominant hand or foot in the ice water, can induce cortical activities. The perception of pain induced by CPT can be related to cortical neurovascular coupling. Hence, the variation of cortical hemodynamic signals during CPT can be an indicator for studying neurovascular coupling. Here, we study the effect of pain induced by CPT on the temporal variation of concentration of oxyhemoglobin [HbO2] and deoxyhemoglobin [Hb] in the healthy brains. We use fNIRS data collected on forehead during a CPT from 11 healthy subjects, and the average data are compared with post-stimulus pain rating scores. The results show that the variation of [Hb] and [HbO2] are positively correlated with self-reported scores during the CPT. These results depict that fNIRS can be potentially applied to study the decoupling of neurovascular process in brain pathological conditions.

The Effect of Knee Flexion Angle on the Neurovascular Safety of All-Inside Lateral Meniscus Repair: A Cadaveric Study.

PubMed

Cuéllar, Adrián; Cuéllar, Ricardo; Cuéllar, Asier; Garcia-Alonso, Ignacio; Ruiz-Ibán, Miguel Angel

2015-11-01

To evaluate if different knee flexion angles can modify the neurovascular injury risk during lateral meniscus repair. Twenty cadaveric knees were studied. An all-inside suture device (FasT-Fix; Smith & Nephew, Andover, MA) was placed at the posterior horn and at the medial and lateral limits of the popliteal hiatus. The minimal distances between the device and the popliteal artery and peroneal nerve were measured with the knee at 90°, 45°, and 0° of flexion through a limited posterolateral arthrotomy. The distance between the device when inserted at the lateral edge of the popliteal hiatus and the peroneal nerve decreased from a median of 26 mm (interquartile range [IQR], 3.5 mm; range, 19 to 29 mm) at 90° to 21.5 mm (IQR, 4.5 mm; range, 14 to 25 mm) at 45° and 15.5 mm (IQR, 6.5 mm; range, 4 to 20 mm) at 0° (significant differences, P < .001). The distance between the device when inserted at the medial edge of the popliteal hiatus and the peroneal nerve decreased from 16 mm (IQR, 3.3 mm; range, 9 to 21 mm) at 90° to 12 mm (IQR, 4.3 mm; range, 9 to 16 mm) at 45° and 7 mm (IQR, 4.0; range, 4 to 15 mm) at 0° (significant differences, P < .001). The distance between the device when inserted at the medial edge of the popliteal hiatus and the popliteal artery decreased from 21 mm (IQR, 5.0 mm; range, 11 to 27 mm) at 90° to 19 mm (IQR, 5.0 mm; range, 10 to 23 mm) at 45° and 16 mm (IQR, 7.5 mm; range, 10 to 23 mm) at 0° (significant differences, P < .001). The distance between the device when inserted 5 mm lateral to the posterior root of the lateral meniscus and the popliteal artery decreased from 13 mm (IQR, 4.3 mm; range, 7 to 27 mm) at 90° to 10.5 mm (IQR, 4.3 mm; range, 4 to 19 mm) at 45° and 5.5 mm (IQR, 4.0 mm; range, 0 to 14 mm) at 0° (significant differences, P < .001). The risk of injury to the popliteal artery or to the peroneal nerve during all-inside repair of the posterior half of the lateral meniscus is lower at 90° of flexion and increases

The SubCons webserver: A user friendly web interface for state-of-the-art subcellular localization prediction.

PubMed

Salvatore, M; Shu, N; Elofsson, A

2018-01-01

SubCons is a recently developed method that predicts the subcellular localization of a protein. It combines predictions from four predictors using a Random Forest classifier. Here, we present the user-friendly web-interface implementation of SubCons. Starting from a protein sequence, the server rapidly predicts the subcellular localizations of an individual protein. In addition, the server accepts the submission of sets of proteins either by uploading the files or programmatically by using command line WSDL API scripts. This makes SubCons ideal for proteome wide analyses allowing the user to scan a whole proteome in few days. From the web page, it is also possible to download precalculated predictions for several eukaryotic organisms. To evaluate the performance of SubCons we present a benchmark of LocTree3 and SubCons using two recent mass-spectrometry based datasets of mouse and drosophila proteins. The server is available at http://subcons.bioinfo.se/. © 2017 The Protein Society.

Somatic cell nuclear transfer: pros and cons.

PubMed

Sumer, Huseyin; Liu, Jun; Tat, Pollyanna; Heffernan, Corey; Jones, Karen L; Verma, Paul J

2009-01-01

Even though the technique of mammalian SCNT is just over a decade old it has already resulted in numerous significant advances. Despite the recent advances in the reprogramming field, SCNT remains the bench-mark for the generation of both genetically unmodified autologous pluripotent stem cells for transplantation and for the production of cloned animals. In this review we will discuss the pros and cons of SCNT, drawing comparisons with other reprogramming methods.

Conserva a Puerto Rico con bosques maderables

Treesearch

Frank H. Wadsworth

2009-01-01

[article in Spanish] Puerto Rico consume muchos productos forestales costosos de importar. También tiene bosques extensos con maderas explotables. Además, existen condiciones físicas favorables para la producción de madera útil. No obstante, hoy día no se utiliza la madera de los bosques actuales ocurre la deforestación para cualquier fin. Los Bosques productivos de...

DESAFÍOS ÉTICOS DE LA INVESTIGACIÓN CON ANIMALES, MANIPULACIÓN GENÉTICA

PubMed Central

Yunta, Eduardo Rodríguez

2012-01-01

En la investigación con animales existen cuestionamientos éticos tanto en el uso como modelos de enfermedades humanas y requisito previo para ensayos en humanos como en la introducción de modificaciones genéticas. Algunos de estos cuestionamientos son: no representar exactamente la condición humana como modelos, realizar pruebas de toxicidad con grave daño para los animales, alterar su naturaleza mediante modificaciones genéticas, riesgos de la introducción de organismos genéticamente modificados. El uso de animales en investigación para beneficio humano, impone al ser humano la responsabilidad moral de respetarlo, no haciéndoles sufrir innecesariamente, al estar trabajando con seres vivientes y sentientes. PMID:23338641

Con Edison power failure of July 13 and 14, 1977. Final staff report

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1978-06-01

On July 13, 1977 the entire electric load of the Con Edison system was lost, plunging New York City and Westchester County into darkness. The collapse resulted from a combination of natural events, equipment malfunctions, questionable system-design features, and operating errors. An attempt is made in this report to answer the following: what were the specific causes of the failure; if equipment malfunctions and operator errors contributed, could they have been prevented; to what extent was Con Edison prepared to handle such an emergency; and did Con Edison plan prudently reserve generation, for reserve transmission capability, for automatic equipment tomore » protect its system, and for proper operator response to a critical situation. Following the introductory and summary section, additional sections include: the Consolidated Edison system; prevention of bulk power-supply interruptions; the sequence of failure and restoration; analysis of the July 1977 power failure; restoration sequence and equipment damage assessment; and other investigations of the blackout. (MCW)« less

Providers debate pros and cons of pneumonia vaccination at discharge.

PubMed

2001-02-01

When to vaccinate against pneumonia? Does it makes sense when patients are in the hospital? Or should patients wait for the first post-op visit with the PCP? Office-based and hospital-based physicians weigh the pros and cons of each.

[Trampoline accident with anterior knee dislocation caused popliteal artery disruption].

PubMed

Pedersen, Peter Heide; Høgh, Annette Langager

2011-10-17

Only a few reports describe the risk of neurovascular damage following knee dislocation while trampolining. A 16 year-old male in a trampoline accident, sustained multi-ligament damage and occlusion of the popliteal artery. The occlusion did not show clinically until 24 hours after the trauma. He underwent vascular surgery (short saphenous bypass). We recommend implementing algorithms, for the management of suspected knee dislocation and possible accompanying neurovascular injuries in all trauma centers.

Cue-based assertion classification for Swedish clinical text – developing a lexicon for pyConTextSwe

PubMed Central

Velupillai, Sumithra; Skeppstedt, Maria; Kvist, Maria; Mowery, Danielle; Chapman, Brian E.; Dalianis, Hercules; Chapman, Wendy W.

2014-01-01

Objective The ability of a cue-based system to accurately assert whether a disorder is affirmed, negated, or uncertain is dependent, in part, on its cue lexicon. In this paper, we continue our study of porting an assertion system (pyConTextNLP) from English to Swedish (pyConTextSwe) by creating an optimized assertion lexicon for clinical Swedish. Methods and material We integrated cues from four external lexicons, along with generated inflections and combinations. We used subsets of a clinical corpus in Swedish. We applied four assertion classes (definite existence, probable existence, probable negated existence and definite negated existence) and two binary classes (existence yes/no and uncertainty yes/no) to pyConTextSwe. We compared pyConTextSwe’s performance with and without the added cues on a development set, and improved the lexicon further after an error analysis. On a separate evaluation set, we calculated the system’s final performance. Results Following integration steps, we added 454 cues to pyConTextSwe. The optimized lexicon developed after an error analysis resulted in statistically significant improvements on the development set (83% F-score, overall). The system’s final F-scores on an evaluation set were 81% (overall). For the individual assertion classes, F-score results were 88% (definite existence), 81% (probable existence), 55% (probable negated existence), and 63% (definite negated existence). For the binary classifications existence yes/no and uncertainty yes/no, final system performance was 97%/87% and 78%/86% F-score, respectively. Conclusions We have successfully ported pyConTextNLP to Swedish (pyConTextSwe). We have created an extensive and useful assertion lexicon for Swedish clinical text, which could form a valuable resource for similar studies, and which is publicly available. PMID:24556644

An Application of Con-Resistant Trust to Improve the Reliability of Special Protection Systems within the Smart Grid

DTIC Science & Technology

2012-06-01

in an effort to be more reliable and efficient. However, with the benefits of this new technology comes added risk . This research utilizes a con ...AN APPLICATION OF CON -RESISTANT TRUST TO IMPROVE THE RELIABILITY OF SPECIAL PROTECTION SYSTEMS WITHIN THE SMART GRID THESIS Crystal M. Shipman...Government and is not subject to copyright protection in the United States AFIT/GCO/ENG/12-22 AN APPLICATION OF CON -RESISTANT TRUST TO IMPROVE THE

Gestational surrogacy: could be a way to be a way to reproduction? Pros and cons.

PubMed

Clementina, Peris

2011-06-01

The aim of this article was to address pros and cons of gestational surrogacy, the social and psychological issues involved in surrogate motherhood triads. Pros and cons of surrogacy, the possible insurgence of a hematologic disease in the fetus, hemolytic disease of the newborn, naturally acquired microchimerism in surrogacy cases, ethical, medical, psychologic, legal and religious issues of a problem are discussed.

Young women's perspective of the pros and cons to seeking screening for chlamydia and gonorrhea: an exploratory study.

PubMed

Chacko, Mariam R; von Sternberg, Kirk; Velasquez, Mary M; Wiemann, Constance M; Smith, Peggy B; DiClemente, Ralph

2008-08-01

To identify young women's pros and cons (decisional balance) to seeking chlamydia (CT) and gonorrhea (NGC) screening. Prospective, cross sectional study Community-based reproductive health clinic 192 young women (66% African American; mean age 18.9 years). Content analysis of responses obtained during a decisional balance exercise (pros and cons) promoting CT and NGC screening was conducted. Thematic categories were developed through a coding process, and each response was assigned to one thematic category. The frequency of pros and cons responses for each category and the frequency of participants endorsing each category were calculated. Ten thematic categories in relation to pros and cons of seeking CT and NGC screening were: being healthy; awareness of the body; systemic factors around the clinic visit and testing procedures; benefits and aversions around treatment; partner trust issues; confidentiality; prevention of long term adverse effects, protection of the body; concern for others; fear of results/aversion to testing; and logistical barriers. The three most often cited pros were awareness of the body, being healthy and treatment issues; and the three most often cited cons were logistical barriers (time/transportation), fear/aversion to testing, and systemic factors. A variety of pros and cons to seeking CT and NGC screening were identified at a community-based clinic. Providers in clinical settings can utilize this information when encouraging patients to seek regular STI screening by elucidating and emphasizing those pros and cons that have the most influence on a young woman's decision-making to seek screening.

Utilice en forma segura los productos con cebo para roedores

EPA Pesticide Factsheets

Si se usan de manera inadecuada, los productos con veneno para ratas y ratones podrían hacerle daño a usted, a sus hijos o a sus mascotas. Siempre que use pesticidas lea la etiqueta del producto y siga todas las indicaciones.

Single step purification of concanavalin A (Con A) and bio-sugar production from jack bean using glucosylated magnetic nano matrix.

PubMed

Kim, Ho Myeong; Cho, Eun Jin; Bae, Hyeun-Jong

2016-08-01

Jack bean (JB, Canavalia ensiformis) is the source of bio-based products, such as proteins and bio-sugars that contribute to modern molecular biology and biomedical research. In this study, the use of jack bean was evaluated as a source for concanavalin A (Con A) and bio-sugar production. A novel method for purifying Con A from JBs was successfully developed using a glucosylated magnetic nano matrix (GMNM) as a physical support, which facilitated easy separation and purification of Con A. In addition, the enzymatic conversion rate of 2% (w/v) Con A extracted residue to bio-sugar was 98.4%. Therefore, this new approach for the production of Con A and bio-sugar is potentially useful for obtaining bio-based products from jack bean. Copyright © 2016 Elsevier Ltd. All rights reserved.

The role of the 2H4 molecule in the generation of suppressor function in Con A-activated T cells.

PubMed

Morimoto, C; Letvin, N L; Rudd, C E; Hagan, M; Takeuchi, T; Schlossman, S F

1986-11-15

The molecular basis for the suppression generated in a concanavalin A (Con A)-activated T cell culture remains unknown. In this study, we have attempted to determine whether the 2H4 and 4B4 molecules on Con A-activated T cells play some role in the generation of suppression by such cells. We have shown that Con A-activated suppressor cells belong to the 2H4+ subset of T cells but not the 4B4+ (2H4-) subset. Con A-activated T cells exerted their optimal suppressor function on day 2 in culture, a time at which the expression of 2H4 on such cells was maximal and 4B4 was minimal. Furthermore, the stimulation of T cells with the higher concentration of Con A generated the stronger suppressor function. At the same time, both 2H4 expression and density were increased and 4B4 expression and density were decreased on such Con A-activated T cells. More importantly, the treatment of Con A-activated T cells with anti-2H4 antibody but not with anti-4B4, anti-TQ1, or anti-T4 antibodies can block the suppressor function of such cells. Taken together, the above results strongly suggest that the 2H4 molecule itself may be involved in the generation of suppressor function in Con A-activated T cells. The 2H4 antigen on such cells was shown to be comprised of 220,000 and 200,000 m.w. glycoproteins. Thus this study indicates that the 220,000 and 200,000 m.w. structure of the 2H4 molecule may itself play a crucial role in the generation of suppressor signals of Con A-activated cells.

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed

de Leeuw, Peter A J; Golanó, Pau; Clavero, Joan A; van Dijk, C Niek

2010-05-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7-1.5) and 0.7 cm (range 0.5-0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy.

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed Central

Golanó, Pau; Clavero, Joan A.; van Dijk, C. Niek

2010-01-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7–1.5) and 0.7 cm (range 0.5–0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy. PMID:20217392

Hacia el consumo informado de tabaco en México: efecto de las advertencias con pictogramas en población fumadora

PubMed Central

Thrasher, James F; Pérez-Hernández, Rosaura; Arillo-Santillán, Edna; Barrientos-Gutiérrez, Inti

2015-01-01

Resumen Objetivo Evaluar el efecto de las advertencias sanitarias (AS) con pictogramas en las cajetillas de tabaco en adultos fumadores. Material y métodos Cohorte de fumadores con representatividad poblacional de siete ciudades mexi canas, antes (2010) y después (2011) de la implementación de AS con pictogramas (ASP). Para determinar el cambio en las variables sobre el impacto cognitivo y conductual de las advertencias, se estimaron modelos bivariados y ajustados de ecuaciones de estimación generalizada. En el Segundo levantamiento (2011), se estimaron modelos para determiner los factores que se asocian con el reporte de recordar cada advertencia que había entrado al mercado, además de los factores asociados con el autorreporte del impacto de cada advertencia vigente. Resultados Se observaron incrementos importantes de 2010 a 2011 en los conocimientos sobre los riesgos de fumar, los componentes tóxicos del tabaco y el número telefónico para recibir consejos sobre dejar de fumar. La recordación e impacto de las primeras advertencias con pictogramas parecen ser amplios y equitativos a través de la población fumadora. En comparación con 2010, un mayor nivel de ex fumadores entrevistados en 2011 reportaron que las advertencias habían influido mucho en dejar de fumar (RM=2.44, 95% IC 1.27–4.72). Conclusiones Las AS con pictogramas han logrado un impacto importante en el conocimiento y conducta, información relevante para la población y en tomadores de decisiones. PMID:22689162

Self-efficacy, pros, and cons as variables associated with adjacent stages of change for regular exercise in Japanese college students.

PubMed

Horiuchi, Satoshi; Tsuda, Akira; Kobayashi, Hisanori; Fallon, Elizabeth A; Sakano, Yuji

2017-07-01

This study examined self-efficacy (confidence to exercise), pros (exercise's advantages), and cons (exercise's disadvantages) as variables associated across the transtheoretical model's six stages of change in 403 Japanese college students. A series of logistic regression analyses were conducted. Results showed that higher pros and lower cons were associated with being in contemplation compared to precontemplation. Lower cons were associated with being in preparation compared to contemplation. Higher self-efficacy was associated with being in action compared to preparation as well as being in maintenance compared to action. Lower cons were associated with being in termination compared to maintenance.

Changes to perceptions of the pros and cons of genetic susceptibility testing after APOE genotyping for Alzheimer disease risk

PubMed Central

Christensen, Kurt D.; Roberts, J. Scott; Uhlmann, Wendy R.; Green, Robert C.

2011-01-01

Purpose Perceptions about the pros and cons of genetic susceptibility testing are among the best predictors of test utilization. How actual testing changes such perceptions has yet to be examined. Methods In a clinical trial, first-degree relatives of patients with Alzheimer disease received genetic risk assessments for Alzheimer disease including APOE disclosure. Participants rated 11 possible benefits associated with genetic testing (pros) and 10 risks or limitations (cons) before genetic risk disclosure and again 12 months afterward. Results Pros were rated higher than cons at baseline (3.53 vs. 1.83, P < 0.001) and at 12 months after risk disclosure (3.33 vs. 1.88, P < 0.001). Ratings of pros decreased during the 12-month period (3.33 vs. 3.53, P < 0.001). Ratings of cons did not change (1.88 vs. 1.83, P = 0.199) except for a three-item discrimination subscale which increased (2.07 vs. 1.92, P = 0.012). Among specific pros and cons, three items related to prevention and treatment changed the most. Conclusion The process of APOE genetic risk assessment for Alzheimer disease sensitizes some to its limitations and the risks of discrimination; however, 1-year after disclosure, test recipients still consider the pros to strongly outweigh the cons. PMID:21270636

Perceived pros and cons of smoking and quitting in hard-core smokers: a focus group study

PubMed Central

2014-01-01

Background In the last decade, so-called hard-core smokers have received increasing interest in research literature. For smokers in general, the study of perceived costs and benefits (or ‘pros and cons’) of smoking and quitting is of particular importance in predicting motivation to quit and actual quitting attempts. Therefore, this study aims to gain insight into the perceived pros and cons of smoking and quitting in hard-core smokers. Methods We conducted 11 focus group interviews among current hard-core smokers (n = 32) and former hard-core smokers (n = 31) in the Netherlands. Subsequently, each participant listed his or her main pros and cons in a questionnaire. We used a structural procedure to analyse the data obtained from the group interviews and from the questionnaires. Results Using the qualitative data of both the questionnaires and the transcripts, the perceived pros and cons of smoking and smoking cessation were grouped into 6 main categories: Finance, Health, Intrapersonal Processes, Social Environment, Physical Environment and Food and Weight. Conclusions Although the perceived pros and cons of smoking in hard-core smokers largely mirror the perceived pros and cons of quitting, there are some major differences with respect to weight, social integration, health of children and stress reduction, that should be taken into account in clinical settings and when developing interventions. Based on these findings we propose the ‘Distorted Mirror Hypothesis’. PMID:24548463

YOUNG WOMEN’S PERSPECTIVE OF THE PROS AND CONS TO SEEKING SCREENING FOR CHLAMYDIA AND GONORRHEA: AN EXPLORATORY STUDY

PubMed Central

Chacko, Mariam R.; von Sternberg, Kirk; Velasquez, Mary M.; Wiemann, Constance M.; Smith, Peggy B.; DiClemente, Ralph

2008-01-01

Study Objective To identify young women’s pros and cons (decisional balance) to seeking chlamydia (CT) and gonorrhea (NGC) screening. Design Prospective, cross sectional study Setting Community-based reproductive health clinic Participants 192 young women (66% African American; mean age 18.9 years). Main Outcome Measure(s) Content analysis of responses obtained during a decisional balance exercise (pros and cons) promoting CT and NGC screening was conducted. Thematic categories were developed through a coding process, and each response was assigned to one thematic category. The frequency of pros and cons responses for each category and the frequency of participants endorsing each category were calculated. Results Ten thematic categories in relation to pros and cons of seeking CT and NGC screening were: being healthy; awareness of knowing the body; systemic factors around the clinic visit and testing procedures; benefits and aversions around treatment; partner relationship issues; confidentiality; prevention of long term adverse effects, protection of the body; concern for others; fear of results/aversion to testing; and logistical barriers. The three most often cited pros were awareness, healthy and treatment issues; and the three most often cited cons were logistical barriers (time/transportation), fear/aversion to testing, and systemic issues. Conclusions A variety of pros and cons to seeking CT and NGC screening were identified at a community-based clinic. Providers in clinical settings can utilize this information when encouraging patients to seek regular STI screening by elucidating and emphasizing those pros and cons that have the most influence on a young woman’s decision-making to seek screening. PMID:18656072

CHILES Con Pol: An ultra-deep JVLA survey probing galaxy evolution and cosmic magnetism

NASA Astrophysics Data System (ADS)

Hales, Christopher A.; Momjian, Emmanuel; van Gorkom, Jacqueline; Rupen, Michael P.; Greiner, Maksim; Ensslin, Torsten A.; Bonzini, Margherita; Padovani, Paolo; Harrison, Ian; Brown, Michael L.; Gim, Hansung; Yun, Min S.; Maddox, Natasha; Stewart, Adam; Fender, Rob P.; Tremou, Evangelia; Chomiuk, Laura; Peters, Charee; Wilcots, Eric M.; Lazio, Joseph

2015-08-01

We are undertaking a 1000 hour campaign with the Karl G. Jansky VLA to survey 0.2 square degrees of the COSMOS field in full polarization continuum at 1.4 GHz. Our observations are part of a joint program with the spectral line COSMOS HI Large Extragalactic Survey (CHILES). When complete, we expect our CHILES Continuum Polarization (CHILES Con Pol) survey to reach an SKA-era sensitivity of 500 nJy per 4 arcsecond resolving beam, the deepest view of the radio sky yet. CHILES Con Pol will open new and fertile parameter space, with sensitivity to star formation rates of 10 Msun per year out to an unprecedented redshift of z=2, and ultra-luminous infrared galaxies and sub-millimeter galaxies out to redshifts of z=8 and beyond. This rich resource will extend the utility of radio band studies beyond the usual radio quasar and radio galaxy populations, opening sensitivity to the starforming and radio-quiet AGN populations that form the bulk of extragalactic sources detected in the optical, X-ray, and infrared bands. In this talk I will outline the key science of CHILES Con Pol, including galaxy evolution and novel measurements of intergalactic magnetic fields. I will present initial results from the first 180 hours of the survey and describe our forthcoming Data Release 1. I invite the astronomical community to consider unique science that can be pursued with CHILES Con Pol radio data.

Hemifacial Spasm and Neurovascular Compression

PubMed Central

Lu, Alex Y.; Yeung, Jacky T.; Gerrard, Jason L.; Michaelides, Elias M.; Sekula, Raymond F.; Bulsara, Ketan R.

2014-01-01

Hemifacial spasm (HFS) is characterized by involuntary unilateral contractions of the muscles innervated by the ipsilateral facial nerve, usually starting around the eyes before progressing inferiorly to the cheek, mouth, and neck. Its prevalence is 9.8 per 100,000 persons with an average age of onset of 44 years. The accepted pathophysiology of HFS suggests that it is a disease process of the nerve root entry zone of the facial nerve. HFS can be divided into two types: primary and secondary. Primary HFS is triggered by vascular compression whereas secondary HFS comprises all other causes of facial nerve damage. Clinical examination and imaging modalities such as electromyography (EMG) and magnetic resonance imaging (MRI) are useful to differentiate HFS from other facial movement disorders and for intraoperative planning. The standard medical management for HFS is botulinum neurotoxin (BoNT) injections, which provides low-risk but limited symptomatic relief. The only curative treatment for HFS is microvascular decompression (MVD), a surgical intervention that provides lasting symptomatic relief by reducing compression of the facial nerve root. With a low rate of complications such as hearing loss, MVD remains the treatment of choice for HFS patients as intraoperative technique and monitoring continue to improve. PMID:25405219

NREL, NYSERDA, and Con Edison Partner on Home Energy Management Systems |

Science.gov Websites

at large scale, the overall impact could be a win-win for both homeowners and utilities, which could sources. Founded in 1823, Con Edison provides electric, gas, and steam service to 10 million people who

Angio-OCT de la zona avascular foveal en ojos con oclusión venosa de la retina.

PubMed

Wons, Juliana; Pfau, Maximilian; Wirth, Magdalena A; Freiberg, Florentina J; Becker, Matthias D; Michels, Stephan

2017-07-11

Objetivo: El objetivo del estudio comprendía visualizar y cuantificar las alteraciones patológicas de la zona avascular foveal (ZAF) mediante angio-OCT en ojos con oclusión venosa de la retina (OVR) en comparación con el ojo contralateral sano. Procedimientos: La angio-OCT se llevó a cabo mediante el sistema Avanti® RTVue 100 XR (Optovue Inc., Fremont, Calif., EE. UU.). Los bordes de la capa vascular superficial (CVS) se definieron como 3 μm por debajo de la membrana limitante interna y 15 μm por debajo de la capa plexiforme interna y, para la capa vascular profunda (CVP), como 15 y 70 μm por debajo de la membrana limitante interna y de la capa plexiforme interna, respectivamente. La longitud de la ZAF horizontal, vertical y máxima de la CVS y la CVP en cada ojo se midió de forma manual. Además, se midió el ángulo entre el diámetro máximo de la ZAF y el plano papilomacular. Resultados: La angio-OCT representó los defectos dentro de la vasculatura en el área perifoveal en ojos con oclusión de rama venosa de la retina (ORVR; n = 11) y con oclusión de la vena central de la retina (OVCR; n = 8). Esto resultó en un crecimiento del diámetro máximo de la ZAF en ojos con OVR (n = 19) en comparación con el ojo contralateral (n = 19; 921 ± 213 frente a 724 ± 145 µm; p = 0,008). Además, se observó una correlación significativa entre la mejor agudeza visual corregida (MAVC) y el diámetro máximo de la ZAF en la CVP (ρ de Spearman = -0,423, p < 0,01). Por último, en los ojos con OVR, el ángulo entre el plano papilomacular y el diámetro máximo de la ZAF se dio tan solo en el 21,05% (CVS) y en el 15,79% (CVP) de los casos a 0 ± 15 ó 90 ± 15°, respectivamente. En ojos sanos, estos ángulos (que supuestamente representan una configuración de la ZAF regular) fueron más prevalentes (CVS 68,42 frente a 21,05%, p = 0,003; CVP 73,68 frente a 15,79%, p < 0,001). Conclusiones: La angio-OCT muestra alteraciones morfológicas de la ZAF en ojos con

The International Consortium for the Investigation of Renal Malignancies (I-ConFIRM)

Cancer.gov

The International Consortium for the Investigation of Renal Malignancies (I-ConFIRM) was formed to promote international, multidisciplinary collaborations to advance our understanding of the etiology and outcomes of kidney cancer.

Detail of conning tower atop the submarine. Note the wire ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of conning tower atop the submarine. Note the wire rope wrapped around the base of the tower, which may have been used in an attempt to pull the submarine offshore. - Sub Marine Explorer, Located along the beach of Isla San Telmo, Pearl Islands, Isla San Telmo, Former Panama Canal Zone, CZ

Estudio de los Efectos Gravitomagnéticos en Cuerpos Masivos Rotantes

NASA Astrophysics Data System (ADS)

Velandia Heredia, N.; Tejeiro, J. M.

2008-03-01

A partir del estudio de los Efectos Gravitomagnéticos en cuerpos masivos rotantes, planteamos la expresión para medir el desfase en el tiempo, para diferentes observadores, que se dan cuando viajan dos rayos de luz por una guía de onda o de manera libre (geodésicas), en el plano azimutal y en el plano polar. Con lo anterior queremos abordar el experimento tipo Michelson y Morley, de forma que podamos involucrar el valor de la densidad del momento angular (a) en el retraso temporal para los dos haces de luz que viajan por los brazos del interferómetro, cuando este último es ubicado en el plano ecuatorial.

End-User Use of Data Base Query Language: Pros and Cons.

ERIC Educational Resources Information Center

Nicholes, Walter

1988-01-01

Man-machine interface, the concept of a computer "query," a review of database technology, and a description of the use of query languages at Brigham Young University are discussed. The pros and cons of end-user use of database query languages are explored. (Author/MLW)

Papiloma invertido sinunasal con invasión intracraneal: Reporte de caso y revisión bibliográfica

PubMed Central

Di Pietrantonio, Andrés; Asmus, Humberto; Ingratta, Christian; Brennan, Walter; Schulz, Javier; Carballo, Leandro

2018-01-01

Resumen IntroducciÓn: El papiloma invertido es una neoplasia benigna de los senos paranasales localmente agresiva con alto potencial de recurrencia y de malignización. La extensión intracraneal es infrecuente y más aún, la penetración dural, asociándose a menudo a la recurrencia de la enfermedad o a su degeneración en carcinoma de células escamosas. Caso clínico: Presentamos el caso de una paciente de 32 años que consultó por lesión exofítica en fosa nasal derecha y exoftalmos, asociada a cefalea, anosmia y disgeusia. Se estudió con TC cerebro, macizo facial y RM de encéfalo que evidencian lesión en fosa nasal derecha con ocupación de senos aéreos, osteólisis de pared medial orbitaria y base de cráneo anterior e invasión intracraneal frontal derecha, con efecto de masa y compresión del parénquima encefálico adyacente. Intervención: Se realizó una nasofibroscopía en primer tiempo con diagnóstico anatomopatológico de papiloma invertido y posteriormente resección de la lesión mediante doble abordaje más reconstrucción de la fosa craneal anterior. Se obtuvo diagnóstico definitivo de papiloma invertido de tipo Schneideriano con áreas de transformación atípica in situ. La paciente evolucionó de forma favorable y sin complicaciones, con permeabilidad de vía aérea superior, sin signos de recidiva lesional luego de 4 años de seguimiento. Conclusión: La invasión intracraneal de esta patología es sumamente infrecuente. Cuando existe, es indicador de agresividad y potencial recidiva, por lo que la exéresis completa de la misma define el pronóstico de la enfermedad. PMID:29430328

Prevalencia y tamizaje del Trastorno por Déficit de Atención con Hiperactividad en Costa Rica

PubMed Central

Weiss, Nicholas T.; Schuler, Jovita; Monge, Silvia; McGough, James J.; Chavira, Denise; Bagnarello, Monica; Herrera, Luis Diego; Mathews, Carol A.

2015-01-01

Resumen La investigación tuvo como propósito estimar la prevalencia del Trastorno por Déficit de Atención con Hiperactividad (TDAH) en Costa Rica y determinar si la versión en español del cuestionario Swanson Nolan and Pelham Scale IV (SNAP-IV) es un instrumento de tamizaje útil en una población de niños y niñas escolares costarricenses. El instrumento fue entregado a padres y maestros de 425 niños entre 5 y 13 años de edad (promedio = 8.8). Todos fueron evaluados con el instrumento Swanson, Kotkin, Agler, M-Flynn and Pelham Scale (SKAMP). Su diagnóstico fue confirmado con una entrevista clínica. La sensibilidad y la especificidad del SNAP-IV fueron evaluadas como predictores de criterios de diagnóstico según el DSM-IV. La prevalencia puntual en la muestra del TDAH fue del 5%. El tamizaje más preciso lo hizo el SNAP-IV completado por el maestro en un corte de 20%, con una sensibilidad de 96% y una especificidad de un 82%. La sensibilidad de los instrumentos completados por los padres fue más baja que aquella de los maestros. El SNAP-IV completado por las maestras con un corte aislando el 20% de los mayores puntajes categorizó correctamente a un 87% de los sujetos. PMID:22432094

Nuevas observaciones de 3C10 con el VLA*: estudio de la expansión

NASA Astrophysics Data System (ADS)

Reynoso, E. M.; Moffett, D. A.:; Dubner, G. M.; Giacani, E. B.; Reynolds, S. P.; Goss, W. M.; Dickel, J.

Se presentan nuevos resultados sobre la expansión del remanente de la supernova de Tycho a lo largo de un intervalo de 10.9 años, comparando nuevas observaciones tomadas con el VLA a 1375 y 1635 MHz durante 1994 y 1995, con observaciones previas realizadas entre 1983 y 1984 (Dickel y col. ~1991 AJ 101, 2151), usando las mismas configuraciones, anchos de banda, calibradores y tiempos de integración. El coeficiente de expansión se calcula para sectores radiales de 4o de ancho cada uno, ajustando la correlación cruzada de las derivadas de los perfiles promedio para cada época. A partir de la expansión medida, se estima el índice (parámetro de expansión) de la ley potencial R∝ tm como m≡ d ln R/d ln t . Este valor se compara con coeficientes teóricos para diferentes fases evolutivas de remanentes de supernova.

Soluciones analiticas AL problema de jets con velocidad de eyeccion variable EN EL tiempo.

NASA Astrophysics Data System (ADS)

Canto, J.; Raga, A. C.; D'Alessio, P.

1998-11-01

Se presenta un nuevo metodo que permite resolver de manera exacta y analitica las ecuaciones que describen un jet hipersonico con velocidad de eyeccion variable en el tiempo. El metodo se basa en consideraciones sencillas de conservacion de momento para las superficies de trabajo que se forman en el interior del jet. Como ejemplo, se presentan soluciones para jets con variacion sinusoidal en la velocidad de eyeccion, y tambien para el caso de un incremento lineal en el tiempo. Estas soluciones analiticas tienen una clara aplicacion en la interpretacion de las observaciones de jets asociados a objetos Herbig-Haro.

Air Traffic Management Technology Demonstration-1 Concept of Operations (ATD-1 ConOps)

NASA Technical Reports Server (NTRS)

Baxley, Brian T.; Johnson, William C.; Swenson, Harry; Robinson, John E.; Prevot, Thomas; Callantine, Todd; Scardina, John; Greene, Michael

2012-01-01

The operational goal of the ATD-1 ConOps is to enable aircraft, using their onboard FMS capabilities, to fly Optimized Profile Descents (OPDs) from cruise to the runway threshold at a high-density airport, at a high throughput rate, using primarily speed control to maintain in-trail separation and the arrival schedule. The three technologies in the ATD-1 ConOps achieve this by calculating a precise arrival schedule, using controller decision support tools to provide terminal controllers with speeds for aircraft to fly to meet times at a particular meter points, and onboard software providing flight crews with speeds for the aircraft to fly to achieve a particular spacing behind preceding aircraft.

Existing con el Lobo, Traversing la Frontera con Mis Nepantla Coyotes, y Buscando la Vida del Zorro: An Autoethnographic Exploration of a Chicano in Academia

ERIC Educational Resources Information Center

Ramirez, Ernesto Fidel

2017-01-01

This dissertation is the experience of my life, an evolution of platicas I have had con mis coyotes, my Nepantlero guides. I am one Chicano navigating through the mechanisms of a coercive and hegemonic system which limits our advancement in the academy. My ontology, epistemology, and axiology stem from my cultural and family foundations which I…

Thymic lymphocytes. III. Cooperative phenomenon in the proliferation of thymocytes under Con A stimulation.

PubMed

Papiernik, M; Jacobson, J B

1986-01-01

In the present paper, the response of thymocytes to Con A is analyzed in terms of a cooperative phenomenon between medullary thymocytes, cortical thymocytes, thymic accessory cells, and interleukin 2. Medullary thymocytes respond spontaneously to Con A and produce IL-2. The addition of exogenously produced IL-2 enhances their proliferation. Small numbers of cortical (PNA+) thymocytes do not respond to Con A, even in the presence of IL-2-containing supernatant. By increasing the number of PNA+ cells per well, sensitivity to Con A and IL-2 appears. This response may be linked either to the increase in a minor PNA+-responding population and/or to the enhanced contamination by medullary thymocytes and macrophages in non-responding PNA+ thymocyte population. In this hypothesis, either the contaminating cells respond by themselves and/or cooperate with PNA+ cells to induce their proliferation. Coculture of non-responding low numbers of PNA+ thymocytes with Con A- and IL-2-containing supernatant in the presence of PNA- cells containing thymic medullary thymocytes and macrophages always produces a higher response than that of each individual population. These results show that a cooperative phenomenon occurs in the cocultures of PNA+ and PNA- thymic cells. We can show using PNA+ and PNA- thymocytes with different Thy 1 alleles, that indeed both PNA+ and populations participate PNA-thymocytes with different Thy 1 alleles, that indeed both PNA+ and PNA- populations participate in the generation of proliferating cells. We can demonstrate, by lysis experiments with monoclonal antibodies and complement that at the end of coculture, most of the proliferating cells are Lyt 1+, and part are Lyt 2+ or L3T4+. We discuss the fact that the phenotype of the cells after activation does not allow us to deduce the phenotype of their precursors. Lysis of Ia+ cells prior to coculture, reduces the level of the proliferative response but does not modify the percentage of cooperation produced

TU-H-CAMPUS-IeP3-02: Neurovascular 4D Parametric Imaging Using Co-Registration of Biplane DSA Sequences with 3D Vascular Geometry Obtained From Cone Beam CT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balasubramoniam, A; Bednarek, D; Rudin, S

Purpose: To create 4D parametric images using biplane Digital Subtraction Angiography (DSA) sequences co-registered with the 3D vascular geometry obtained from Cone Beam-CT (CBCT). Methods: We investigated a method to derive multiple 4D Parametric Imaging (PI) maps using only one CBCT acquisition. During this procedure a 3D-DSA geometry is stored and used subsequently for all 4D images. Each time a biplane DSA is acquired, we calculate 2D parametric maps of Bolus Arrival Time (BAT), Mean Transit Time (MTT) and Time to Peak (TTP). Arterial segments which are nearly parallel with one of the biplane imaging planes in the 2D parametricmore » maps are co-registered with the 3D geometry. The values in the remaining vascular network are found using spline interpolation since the points chosen for co-registration on the vasculature are discrete and remaining regions need to be interpolated. To evaluate the method we used a patient CT volume data set for 3D printing a neurovascular phantom containing a complete Circle of Willis. We connected the phantom to a flow loop with a peristaltic pump, simulating physiological flow conditions. Contrast media was injected with an automatic injector at 10 ml/sec. Images were acquired with a Toshiba Infinix C-arm and 4D parametric image maps of the vasculature were calculated. Results: 4D BAT, MTT, and TTP parametric image maps of the Circle of Willis were derived. We generated color-coded 3D geometries which avoided artifacts due to vessel overlap or foreshortening in the projection direction. Conclusion: The software was tested successfully and multiple 4D parametric images were obtained from biplane DSA sequences without the need to acquire additional 3D-DSA runs. This can benefit the patient by reducing the contrast media and the radiation dose normally associated with these procedures. Partial support from NIH Grant R01-EB002873 and Toshiba Medical Systems Corp.« less

El proyecto AUGER

NASA Astrophysics Data System (ADS)

Etchegoyen, A.

Hace ya más de 30 años en Volcano Ranch, EE.UU., un extenso chubasco cósmico (ECC) fue detectado con energía en exceso de 1020 eV. Desde entonces, observatorios ubicados en Haverah Park del Reino Unido, Yakutsk de Rusia, AGASA de Japón y Dugway de EE.UU. también han observado ECC con energías mayores que 1020 eV. Poco se sabe de dichos rayos, y en particular cuál es la naturaleza del primario, de dónde provienen, y cómo son acelerados, pero su naturaleza ultrarelativista excluye la mayoría de las respuestas dejando sólo algunas plausibles de ser investigadas experimentalmente. Grupos de científicos de 20 países están trabajando con el fin de construir dos arreglos de detectores gigantes, uno en cada hemisferio a lo largo de 3000 km2 c/u. Dichas dimensiones son necesarias debido al flujo estimado de 1 rayo cósmico/centuria/km2/sr. La sede del Observatorio del Sur es la Argentina. El proyecto fue nombrado Pierre Auger en conmemoración del célebre físico francés que detectó por primera vez chubascos cósmicos en 1938. El proyecto focaliza su interés en rayos cósmicos con energías mayores que 1020 eV.

The physiological functions of central nervous system pericytes and a potential role in pain

PubMed Central

Beazley-Long, Nicholas; Durrant, Alexandra M; Swift, Matthew N; Donaldson, Lucy F

2018-01-01

Central nervous system (CNS) pericytes regulate critical functions of the neurovascular unit in health and disease. CNS pericytes are an attractive pharmacological target for their position within the neurovasculature and for their role in neuroinflammation. Whether the function of CNS pericytes also affects pain states and nociceptive mechanisms is currently not understood. Could it be that pericytes hold the key to pain associated with CNS blood vessel dysfunction? This article reviews recent findings on the important physiological functions of CNS pericytes and highlights how these neurovascular functions could be linked to pain states. PMID:29623199

Genealogy of training in vascular neurosurgery.

PubMed

Chowdhry, Shakeel A; Spetzler, Robert F

2014-02-01

Remarkable advances and changes in the landscape of neurovascular disease have occurred recently. Concurrently, a paradigm shift in training and resident education is underway. This crossroad of unique opportunities and pressures necessitates creative change in the training of future vascular neurosurgeons to allow incorporation of surgical advances, new technology, and supplementary treatment modalities in a setting of reduced work hours and increased public scrutiny. This article discusses the changing landscape in neurovascular disease treatment, followed by the recent changes in resident training, and concludes with our view of the future of training in vascular neurosurgery.

Oxacilin-resistant Coagulase-negative staphylococci (CoNS) bacteremia in a general hospital at São Paulo city, Brasil

PubMed Central

d’Azevedo, P.A.; Secchi, C.; Antunes, A.L.S.; Sales, T.; Silva, F.M.; Tranchesi, R.; Pignatari, A.C.C.

2008-01-01

In the last decades, coagulase-negative staphylococci (CoNS), especially Staphylococcus epidermidis have become an important cause of bloodstream infections. In addition, rates of methicillin-resistance among CoNS have increased substantially, leading to the use of glicopeptides for therapy. The objective of this study was to evaluate eleven consecutives clinically relevant cases of oxacillin-resistant CoNS bacteremia in a general hospital localized in São Paulo city, Brazil. Five different species were identified by different phenotypic methods, including S. epidermidis (5), S. haemolyticus (3), S. hominis (1), S. warneri (1) and S. cohnii subsp urealyticus (1). A variety of Pulsed Field Gel Electrophoresis profiles was observed by macrorestriction DNA analysis in S. epidermidis isolates, but two of three S. haemolyticus isolates presented the same profile. These data indicated the heterogeneity of the CoNS isolates, suggesting that horizontal dissemination of these microorganisms in the investigated hospital was not frequent. One S. epidermidis and one S. haemolyticus isolates were resistant to teicoplanin and susceptible to vancomycin. The selective pressure due to the use of teicoplanin in this hospital is relevant. PMID:24031279

40 CFR 227.27 - Limiting permissible con-cen-tra-tion (LPC).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Limiting permissible con-cen-tra-tion... scientific literature or accepted by EPA as being reliable test organisms to determine the anticipated impact... for each type they represent, and that are documented in the scientific literature and accepted by EPA...

Value of Frequency Domain Resting-State Functional Magnetic Resonance Imaging Metrics Amplitude of Low-Frequency Fluctuation and Fractional Amplitude of Low-Frequency Fluctuation in the Assessment of Brain Tumor-Induced Neurovascular Uncoupling.

PubMed

Agarwal, Shruti; Lu, Hanzhang; Pillai, Jay J

2017-08-01

The aim of this study was to explore whether the phenomenon of brain tumor-related neurovascular uncoupling (NVU) in resting-state blood oxygen level-dependent functional magnetic resonance imaging (BOLD fMRI) (rsfMRI) may also affect the resting-state fMRI (rsfMRI) frequency domain metrics the amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF). Twelve de novo brain tumor patients, who underwent clinical fMRI examinations, including task-based fMRI (tbfMRI) and rsfMRI, were included in this Institutional Review Board-approved study. Each patient displayed decreased/absent tbfMRI activation in the primary ipsilesional (IL) sensorimotor cortex in the absence of a corresponding motor deficit or suboptimal task performance, consistent with NVU. Z-score maps for the motor tasks were obtained from general linear model analysis (reflecting motor activation vs. rest). Seed-based correlation analysis (SCA) maps of sensorimotor network, ALFF, and fALFF were calculated from rsfMRI data. Precentral and postcentral gyri in contralesional (CL) and IL hemispheres were parcellated using an automated anatomical labeling template for each patient. Region of interest (ROI) analysis was performed on four maps: tbfMRI, SCA, ALFF, and fALFF. Voxel values in the CL and IL ROIs of each map were divided by the corresponding global mean of ALFF and fALFF in the cortical brain tissue. Group analysis revealed significantly decreased IL ALFF (p = 0.02) and fALFF (p = 0.03) metrics compared with CL ROIs, consistent with similar findings of significantly decreased IL BOLD signal for tbfMRI (p = 0.0005) and SCA maps (p = 0.0004). The frequency domain metrics ALFF and fALFF may be markers of lesion-induced NVU in rsfMRI similar to previously reported alterations in tbfMRI activation and SCA-derived resting-state functional connectivity maps.

Salud mental en desastres naturales: estrategias interventivas con adultos mayores en sectores rurales de Chile.

PubMed

Osorio-Parraguez, Paulina; Espinoza, Adriana

2016-06-01

En el presente artículo se da a conocer una estrategia de intervención llevada a cabo con adultos mayores en la comuna de Paredones, sexta región de Chile, con posterioridad al terremoto y tsunami del 27 de febrero 2010 en Chile, en el contexto de una investigación sobre fortalezas y vulnerabilidades desplegadas por este grupo etario, con posterioridad a un desastre natural. Se presenta una descripción del desarrollo metodológico de la intervención y de los sustentos teóricos y conceptuales en los que se basa. Como resultado de este proceso, se propone una estrategia que trabaje a través de la identificación de las propias experiencias y fortalezas de los sujetos. De tal forma se minimizan los efectos negativos de los determinantes sociales de la salud (como la edad y el lugar de residencia) en contexto de crisis; permitiendo a los adultos mayores fortalecer sus recursos individuales y colectivos, en pro de su bienestar psicosocial. © The Author(s) 2015.

Talonavicular joint arthroscopic portals: A cadaveric study of feasibility and safety.

PubMed

Xavier, Gabriel; Oliva, Xavier Martin; Rotinen, Mauri; Monzo, Mariano

2016-09-01

The objectives of the study were to evaluate the safety of hypothetical arthroscopic portals from talonavicular joint and to evaluate their reproducibility and enforceability. 19 cadaveric feet were marked and four arthroscopic portals were made (medial, dorsomedial, dorsolateral and lateral). The specimens were dissected in layers and the distances between neurovascular structures and the trocars were measured. Medial and dorsomedial portals were in average 8.3 and 8.7, respectively, to the saphenous vein and nerve. Dorsolateral portal was in average 8.1mm to the deep peroneal nerve and dorsalis pedis artery, and 9.1mm to the medial dorsal cutaneous branch of the superficial peroneal nerve. Lateral portal was in average 12.3mm to the intermediate dorsal cutaneous branch of the superficial peroneal nerve. Tested portals shown to have a good safety margin for the foot neurovascular deep dorsal structures and an acceptable safety margin for the superficial neurovascular structures. Copyright © 2015 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Structure and vascular function of MEKK3–cerebral cavernous malformations 2 complex

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fisher, Oriana S.; Deng, Hanqiang; Liu, Dou

Cerebral cavernous malformations 2 (CCM2) loss is associated with the familial form of CCM disease. The protein kinase MEKK3 (MAP3K3) is essential for embryonic angiogenesis in mice and interacts physically with CCM2, but how this interaction is mediated and its relevance to cerebral vasculature are unknown. Here we report that Mekk3 plays an intrinsic role in embryonic vascular development. Inducible endothelial Mekk3 knockout in neonatal mice is lethal due to multiple intracranial haemorrhages and brain blood vessels leakage. We discover direct interaction between CCM2 harmonin homology domain (HHD) and the N terminus of MEKK3, and determine a 2.35 Å cocrystalmore » structure. We find Mekk3 deficiency impairs neurovascular integrity, which is partially dependent on Rho–ROCK signalling, and that disruption of MEKK3:CCM2 interaction leads to similar neurovascular leakage. We conclude that CCM2:MEKK3-mediated regulation of Rho signalling is required for maintenance of neurovascular integrity, unravelling a mechanism by which CCM2 loss leads to disease.« less

Invasive macrodystrophia lipomatosa of the hand.

PubMed

Colonna, M R; Guarneri, C; do Stagno d'Alcontres, F; Risitano, G; Cavallari, V; Ribuffo, D

2014-01-01

The Authors point out the interest of differential diagnosis and conservative surgical treatment of a rare case of digital and ulnar side of the hand gigantism, with massive fatty infiltration of soft tissues and a neurovascular bundle, to be included into Macrodystrophia Lipomatosa with fibrolipomatous hamartomata. Excision of the mass included 4th ray disarticulation (the fifth had been amputated several years ago) as well as microsurgical external and internal neurolysis of the ulnar nerve, the ulnar neurovascular bundle being exposed and covered with dermal substitute INTEGRATM, with a good result both from a cosmetic and functional point of view at three year follow up. This is the first report of INTEGRATM covering of a neurovascular bundle. Samples taken from the dermal substitute matrix interface at day 6 and day 25 were examined with transmission Electron Microscopy: a newly formed tissue, rich in precursor cells, was detected. Conservative surgery, requiring particular microsurgical skills and use of dermal templates, plays an outstanding role in treatment of these rare but aggressive soft tissues masses of the upper limb.

Catálogo de Radio-Fuentes Opticas con Astrolabio Fotoeléctrico PAII

NASA Astrophysics Data System (ADS)

Manrique, W. T.; Podestá, R. C.; Alonso, E.; Actis, E. V.; Pacheco, A. M.; Bustos, G.; Lizhi, L.; Zezhi, W.; Fanmiao, Z.; Hongqi, W.; Perdomo, R.

Usando los datos observados en San Juan con el Astrolabio Fotoeléctrico PAII desde Febrero de 1992 hasta Marzo de 1997, se ha realizado el Catálogo de Radio-Fuentes Opticas de San Juan conteniendo 69 estrellas. Las observaciones de las posiciones de las radio-fuentes están realizadas para la época y equinoccio J2000,0 y en un sistema cercano al del FK5. Las precisiones medias son ± 2,2 ms y ± 0,"035 en ascensión recta y declinación respectivamente. Las magnitudes de las estrellas son desde 0,9 a 10,7 . Las declinaciones son desde --2,5 grados a --60 grados. La época media es 1995,1. Se muestran también los resultados comparados con el Catálogo Hiparcos.

[Not Available].

PubMed

Pérez-Flores, Juan Emmanuel; Chávez-Tostado, Mariana; Larios-Del-Toro, Youné Elizabeth; García-Rentería, Jesús; Rendrón-Félix, Jorge; Salazar-Parra, Marcela; Irusteta-Jiménez, Leire; Michel-Espinoza, Luis Rodrigo; Márquez-Valdez, Aída Rebeca; Cuesta-Márquez, Lisbeth; Álvarez-Villaseñor, Andrea Socorro; Fuentes-Orozco, Clotilde; González Ojeda, Alejandro

2016-07-19

Introducción: la desnutrición intrahospitalaria se ha descrito hace más de 70 años como un problema frecuente. En México se reportan cifras de entre el 20% al 50%; sin embargo no se ha estudiado su prevalencia ni su asociación con la morbilidad y mortalidad hospitalaria.Objetivos: evaluar el estado nutricional y su relación con la morbimortalidad hospitalaria en pacientes mexicanos.Métodos: cohorte prospectiva de pacientes que ingresaron en un hospital de referencia para una estancia hospitalaria mayor de 5 días. Se capturó peso, talla, índice de masa corporal (IMC), estado nutricional de acuerdo con la valoración global subjetiva (VGS) a su ingreso y egreso hospitalario, así como diagnóstico médico, complicaciones y mortalidad. Los datos fueron analizados mediante la prueba T de Student, prueba Chi-cuadrado y prueba Exacta de Fisher.Resultados: se incluyeron 610 pacientes en total, con un promedio de edad de 50,8 ± 17,32 años, 267 mujeres (43,8%) y 343 hombres (56,2%). Del total, 154 fueron catalogados con sospecha de desnutrición o desnutrición (pacientes expuestos, 25,2%) y 456 bien nutridos (pacientes no expuestos, 74,8%), con una relación de 1 a 3. La morbilidad total de la cohorte tuvo un RR = 2,70, IC 95 % (2,06-3,55) y la mortalidad con un RR = 2,64, IC 95% (1,74-4,0), siendo ambas estadísticamente significativas (p = 0,001).Conclusiones: el diagnóstico de desnutrición al ingreso hospitalario constituye un factor de riesgo para el desarrollo de complicaciones y mortalidad. Este padecimiento al ingreso en comparación con el paciente que no presenta desnutrición incrementó el riesgo de mortalidad hasta en 2.64 veces.

ConSurf 2016: an improved methodology to estimate and visualize evolutionary conservation in macromolecules

PubMed Central

Ashkenazy, Haim; Abadi, Shiran; Martz, Eric; Chay, Ofer; Mayrose, Itay; Pupko, Tal; Ben-Tal, Nir

2016-01-01

The degree of evolutionary conservation of an amino acid in a protein or a nucleic acid in DNA/RNA reflects a balance between its natural tendency to mutate and the overall need to retain the structural integrity and function of the macromolecule. The ConSurf web server (http://consurf.tau.ac.il), established over 15 years ago, analyses the evolutionary pattern of the amino/nucleic acids of the macromolecule to reveal regions that are important for structure and/or function. Starting from a query sequence or structure, the server automatically collects homologues, infers their multiple sequence alignment and reconstructs a phylogenetic tree that reflects their evolutionary relations. These data are then used, within a probabilistic framework, to estimate the evolutionary rates of each sequence position. Here we introduce several new features into ConSurf, including automatic selection of the best evolutionary model used to infer the rates, the ability to homology-model query proteins, prediction of the secondary structure of query RNA molecules from sequence, the ability to view the biological assembly of a query (in addition to the single chain), mapping of the conservation grades onto 2D RNA models and an advanced view of the phylogenetic tree that enables interactively rerunning ConSurf with the taxa of a sub-tree. PMID:27166375

A National Look at Postmodernism's Pros and Cons in Educational Leadership

ERIC Educational Resources Information Center

Townsell, Rhodena

2007-01-01

The purpose of this article is to take a look at the pros and cons of postmodernism. It is imperative for administrators to closely examine educational theories and practices prior to instituting changes. The ability to read and digest challenging material keeps one informed and prepared to lead effectively. This paper will list the pros and cons…

Cervical disc arthroplasty: Pros and cons

PubMed Central

Moatz, Bradley; Tortolani, P. Justin

2012-01-01

Background: Cervical disc arthroplasty has emerged as a promising potential alternative to anterior cervical discectomy and fusion (ACDF) in appropriately selected patients. Despite a history of excellent outcomes after ACDF, the question as to whether a fusion leads to adjacent segment degeneration remains unanswered. Numerous US investigational device exemption trials comparing cervical arthroplasty to fusion have been conducted to answer this question. Methods: This study reviews the current research regarding cervical athroplasty, and emphasizes both the pros and cons of arthroplasty as compared with ACDF. Results: Early clinical outcomes show that cervical arthroplasty is as effective as the standard ACDF. However, this new technology is also associated with an expanding list of novel complications. Conclusion: Although there is no definitive evidence that cervical disc replacement reduces the incidence of adjacent segment degeneration, it does show other advantages; for example, faster return to work, and reduced need for postoperative bracing. PMID:22905327

Cervical disc arthroplasty: Pros and cons.

PubMed

Moatz, Bradley; Tortolani, P Justin

2012-01-01

Cervical disc arthroplasty has emerged as a promising potential alternative to anterior cervical discectomy and fusion (ACDF) in appropriately selected patients. Despite a history of excellent outcomes after ACDF, the question as to whether a fusion leads to adjacent segment degeneration remains unanswered. Numerous US investigational device exemption trials comparing cervical arthroplasty to fusion have been conducted to answer this question. This study reviews the current research regarding cervical athroplasty, and emphasizes both the pros and cons of arthroplasty as compared with ACDF. Early clinical outcomes show that cervical arthroplasty is as effective as the standard ACDF. However, this new technology is also associated with an expanding list of novel complications. Although there is no definitive evidence that cervical disc replacement reduces the incidence of adjacent segment degeneration, it does show other advantages; for example, faster return to work, and reduced need for postoperative bracing.

Safe Corridor to Access Clivus for Endoscopic Trans-Sphenoidal Surgery: A Radiological and Anatomical Study

PubMed Central

Cheng, Ye; Zhang, Siwen; Chen, Yong; Zhao, Gang

2015-01-01

Purpose Penetration of the clivus is required for surgical access of the brain stem. The endoscopic transclivus approach is a difficult procedure with high risk of injury to important neurovascular structures. We undertook a novel anatomical and radiological investigation to understand the structure of the clivus and neurovascular structures relevant to the extended trans-nasal trans-sphenoid procedure and determine a safe corridor for the penetration of the clivus. Method We examined the clivus region in the computed tomographic angiography (CTA) images of 220 adults, magnetic resonance (MR) images of 50 adults, and dry skull specimens of 10 adults. Multiplanar reconstruction (MPR) of the CT images was performed, and the anatomical features of the clivus were studied in the coronal, sagittal, and axial planes. The data from the images were used to determine the anatomical parameters of the clivus and neurovascular structures, such as the internal carotid artery and inferior petrosal sinus. Results The examination of the CTA and MR images of the enrolled subjects revealed that the thickness of the clivus helped determine the depth of the penetration, while the distance from the sagittal midline to the important neurovascular structures determined the width of the penetration. Further, data from the CTA and MR images were consistent with those retrieved from the examination of the cadaveric specimens. Conclusion Our findings provided certain pointers that may be useful in guiding the surgery such that inadvertent injury to vital structures is avoided and also provided supportive information for the choice of the appropriate endoscopic equipment. PMID:26368821

Conning the conmen: Intelligence and female desire in Dedh Ishqiya.

PubMed

Singh, Shailendra Kumar

2018-01-02

This article investigates the ostensibly paradoxical relationship that exists between the theme of excessive love, as suggested by the title of Abhishek Chaubey's film Dedh Ishqiya (2014), and the actual representation of it in the movie, which is not only restrained and disproportionate, but is also looked at with suspicion and contempt. It examines the logic of this seeming contradiction through the other two related themes that Chaubey's chef-d'œuvre foregrounds, namely that of intelligence and female desire. The quest for financial autonomy that the female protagonists of the movie are involved in-a necessary pre-condition for leading independent lives-is so inextricably intertwined with manipulation, dexterity, and subterfuge, that any overt expression of homoerotic female desire can only jeopardize their existing possibilities of self-aggrandizement. The heteronormative arrangements of Begum Para's palace thus constitute the elaborate mise en scène, behind which female desire is enacted through a politics of intelligence, resourcefulness, discretion, and anonymity. Through this strategic negotiation, which is also a tactical necessity, the female protagonists are not only able to con the con men in the movie, but also imagine alternative subject positions that recognize the need for both pragmatism and expediency as well as deconstructing heteropatriarchal economies of desire.

Pros and cons of prognostic disclosure to Japanese cancer patients and their families from the family's point of view.

PubMed

Yoshida, Saran; Shiozaki, Mariko; Sanjo, Makiko; Morita, Tatsuya; Hirai, Kei; Tsuneto, Satoru; Shima, Yasuo

2012-12-01

The primary goals of this analysis were to explore the pros and cons of prognostic disclosure to patients and their families from the bereaved family's point of view. Semistructured interviews were conducted with 60 bereaved family members of patients with cancer in Japan. There were eight categories of influence related to the disclosure of prognosis to the family, including pros (e.g., "Enabling mental preparedness for the patient's death") and cons (e.g., "Being distressed by acknowledging the patient's prognosis"); and seven categories of influence of not disclosing the prognosis to family, including pros (e.g., "Being able to maintain hope") and cons (e.g., "Being prevented from providing adequate care for the patient"). There were also nine categories of influence related to the disclosure of prognosis to patients (e.g., "Enabling various discussions regarding death with the patient"), and eight categories of influence related to not disclosing the prognosis to patients (e.g., "Maintaining the patient's hope"). Although prognostic disclosure to family members can contribute to psychological distress and hopelessness, at the same time, it has the potential to prepare them for the future both emotionally and practically, and also to make the time until the patient's death as meaningful as possible. It is useful for physicians to introduce pros and cons of prognostic disclosure to family members at the time of decision making, to understand the family members' psychological state, and to provide support considering pros and cons whether or not they disclosed prognosis.

Public mental hospital work: pros and cons for psychiatrists.

PubMed

Miller, R D

1984-09-01

The extensive literature concerning public mental hospitals has largely been written from the perspective of administrators and systems analysts; most of the reports emphasize the frustrations and problems of working in public mental hospitals and the continued exodus of psychiatrists from these facilities. The author addresses the pros and cons of such a career choice from the viewpoint of one who has been an "Indian" rather than a "chief" for a decade. He suggests that the current financial situation in both private practice and academia makes work in public mental hospitals increasingly attractive.

Silence, Metaperformance, and Communication in Pedro Almodóvar's "Hable con ella"

ERIC Educational Resources Information Center

Fellie, Maria C.

2016-01-01

Many scenes in Pedro Almodóvar's "Hable con ella" (2002) include shots of metaperformances such as silent films, dances, television shows, concerts, and bullfights. Spectators often observe passive characters who are in turn observing. By presenting these performances within cinematic performance, Almodóvar highlights our role as viewers…

U.S. Exploration EVA: ConOps, Interfaces and Test Objectives for Airlocks

NASA Technical Reports Server (NTRS)

Buffington, J.

2017-01-01

NASA is moving forward on defining the xEVA System Architecture and its implications to the spacecraft that host exploration EVA systems. This presentation provides an overview of the latest information for NASA's Concept of Operations (ConOps), Interfaces and corresponding Test Objectives for Airlocks hosting the xEVA System.

Preventing High Altitude Cerebral Edema in Rats with Repurposed Anti-Angiogenesis Pharmacotherapy.

PubMed

Tarshis, Samantha; Maltzahn, Joanne; Loomis, Zoe; Irwin, David C

2016-12-01

High altitude cerebral edema (HACE) is a fulminant, deadly, and yet still unpredictable brain disease. A new prophylactic treatment for HACE and its predecessor, acute mountain sickness (AMS), needs to be developed without the contraindications or adverse effect profiles of acetazolamide and dexamethasone. Since neovascularization signals are likely key contributors to HACE/AMS, our approach was to examine already existing anti-angiogenic drugs to inhibit potential initiating HACE pathway(s). This approach can also reveal crucial early steps in the frequently debated mechanism of HACE/AMS pathogenesis. We exposed four rat cohorts to hypobaric hypoxia and one to sea level (hyperbaric) conditions. The cohorts were treated with saline controls, an anti-angiogenesis drug (motesanib), a pro-angiogenesis drug (deferoxamine), or an intraperitoneal version of the established AMS prophylaxis drug, acetazolamide (benzolamide). Brain tissue was analyzed for cerebrovascular leak using the Evans Blue Dye (EVBD) protocol. We observed significantly increased EVBD in the altitude control and pro-angiogenesis (deferoxamine) cohorts, and significantly decreased EVBD in the anti-angiogenesis (motesanib), established treatment (benzolamide), and sea-level cohorts. Anti-angiogenesis-treated cohorts demonstrated less cerebrovascular extravasation than the altitude control and pro-angiogenesis treated rats, suggesting promise as an alternative prophylactic HACE/AMS treatment. The leak exacerbation with pro-angiogenesis treatment and improvement with anti-angiogenesis treatment support the hypothesis of early neovascularization signals provoking HACE. We demonstrate statistically significant evidence to guide further investigation for VEGF- and HIF-inhibitors as HACE/AMS prophylaxis, and as elucidators of still unknown HACE pathogenesis.Tarshis S, Maltzahn J, Loomis Z, Irwin DC. Preventing high altitude cerebral edema in rats with repurposed anti-angiogenesis pharmacotherapy. Aerosp Med

Boronic acid-tethered amphiphilic hyaluronic acid derivative-based nanoassemblies for tumor targeting and penetration.

PubMed

Jeong, Jae Young; Hong, Eun-Hye; Lee, Song Yi; Lee, Jae-Young; Song, Jae-Hyoung; Ko, Seung-Hak; Shim, Jae-Seong; Choe, Sunghwa; Kim, Dae-Duk; Ko, Hyun-Jeong; Cho, Hyun-Jong

2017-04-15

(3-Aminomethylphenyl)boronic acid (AMPB)-installed hyaluronic acid-ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated for tumor-targeted delivery. The amine group of AMPB was conjugated to the carboxylic acid group of hyaluronic acid (HA) via amide bond formation, and synthesis was confirmed by spectroscopic methods. HACE-AMPB/MB NPs with a 239-nm mean diameter, narrow size distribution, negative zeta potential, and >90% drug encapsulation efficiency were fabricated. Exposed AMPB in the outer surface of HACE-AMPB NPs (in the aqueous environment) may react with sialic acid of cancer cells. The improved cellular accumulation efficiency, in vitro antitumor efficacy, and tumor penetration efficiency of HACE-AMPB/MB NPs, compared with HACE/MB NPs, in MDA-MB-231 cells (CD44 receptor-positive human breast adenocarcinoma cells) may be based on the CD44 receptor-mediated endocytosis and phenylboronic acid-sialic acid interaction. Enhanced in vivo tumor targetability, infiltration efficiency, and antitumor efficacies of HACE-AMPB NPs, compared with HACE NPs, were observed in a MDA-MB-231 tumor-xenografted mouse model. In addition to passive tumor targeting (based on an enhanced permeability and retention effect) and active tumor targeting (interaction between HA and CD44 receptor), the phenylboronic acid-sialic acid interaction can play important roles in augmented tumor targeting and penetration of HACE-AMPB NPs. STATEMENT OF SIGNIFICANCE: (3-Aminomethylphenyl)boronic acid (AMPB)-tethered hyaluronic acid-ceramide (HACE)-based nanoparticles (NPs), including manassantin B (MB), were fabricated and their tumor targeting and penetration efficiencies were assessed in MDA-MB-231 (CD44 receptor-positive human adenocarcinoma) tumor models. MB, which exhibited antitumor efficacies via the inhibition of angiogenesis and hypoxia inducible factor (HIF)-1, was entrapped in HACE-AMPB NPs in this study. Phenylboronic acid located in the outer surface

Evaluation of ConPrim: A three-part model for continuing education in primary health care.

PubMed

Berggren, Erika; Strang, Peter; Orrevall, Ylva; Ödlund Olin, Ann; Sandelowsky, Hanna; Törnkvist, Lena

2016-11-01

To overcome the gap between existing knowledge and the application of this knowledge in practice, a three-part continuing educational model for primary health care professionals (ConPrim) was developed. It includes a web-based program, a practical exercise and a case seminar. To evaluate professionals' perceptions of the design, pedagogy and adaptation to primary health care of the ConPrim continuing educational model as applied in a subject-specific intervention. A total of 67 professionals (nurses and physicians) completed a computer-based questionnaire evaluating the model's design, pedagogy and adaptation to primary health care one week after the intervention. Descriptive statistics were used. Over 90% found the design of the web-based program and case seminar attractive; 86% found the design of the practical exercise attractive. The professionals agreed that the time spent on two of the three parts was acceptable. The exception was the practical exercise: 32% did not fully agree. Approximately 90% agreed that the contents of all parts were relevant to their work and promoted interactive and interprofessional learning. In response to the statements about the intervention as whole, approximately 90% agreed that the intervention was suitable to primary health care, that it had increased their competence in the subject area, and that they would be able to use what they had learned in their work. ConPrim is a promising model for continuing educational interventions in primary health care. However, the time spent on the practical exercise should be adjusted and the instructions for the exercise clarified. ConPrim should be tested in other subject-specific interventions and its influence on clinical practice should be evaluated. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Advocacy in the Public Forum: The Pro/Con Program at Ohio State.

ERIC Educational Resources Information Center

Stegman, John D.

The Pro/Con Campus Debate and Community Forum program at The Ohio State University serves the educational mission of the department of communication and contributes to the intellectual life of the student body and the larger community by emphasizing the needs of the audience. Eschewing jargon and rhetorical tricks, the program encourages the…

Evaluation of a new automated microscopy urine sediment analyser - sediMAX conTRUST®.

PubMed

Bogaert, Laura; Peeters, Bart; Billen, Jaak

2017-04-01

This study evaluated the performance of the stand-alone sediMAX conTRUST (77Elektronika, Budapest, Hungary) analyser as an alternative to microscopic analysis of urine. The validation included a precision, carry-over, categorical correlation and diagnostic performance study with manual phase-contrast microscopy as reference method. A total of 260 routine urine samples were assessed. The within-run precision was much better at higher concentrations than at very low concentrations. The precision met our predefined limits for all the elements at the different concentrations, with the exception of the lowest RBC, the WBC, pathological casts and crystals count. There was no sample carry-over. The analyser showed good categorical agreement with manual microscopy for RBC and WBC counts, moderate agreement for yeast cells, crystals and squamous epithelial cells and bad agreement for non-squamous epithelial cells, bacteria and casts. Diagnostic performance was satisfying only for RBC, WBC and yeast cells. The number of false negative results was acceptable (≤4%) for all elements after connecting the sediMAX conTRUST with an automatic strip reader (AutionMAX) and after implementation of review rules. We conclude that the sediMAX conTRUST should be used as a screening tool in combination with an automatic strip reader, for the identification of normal samples. Therefore, adequate review rules should be defined. Manual microscopy is still required in 'flagged' pathological samples. Despite the poor analytical performance on pathological samples, the images on the screen can be used for interpretation without the microscope and can be stored as PDF-documents for archiving the results.

Neurovascular regulation in the ischemic brain.

PubMed

Jackman, Katherine; Iadecola, Costantino

2015-01-10

The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory.

Neurovascular Regulation in the Ischemic Brain

PubMed Central

Jackman, Katherine

2015-01-01

Abstract Significance: The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. Recent Advances and Critical Issues: The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Future Directions: Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory. Antioxid. Redox Signal. 22, 149–160. PMID:24328757

The global regulator of pathogenesis PnCon7 positively regulates Tox3 effector gene expression through direct interaction in the wheat pathogen Parastagonospora nodorum.

PubMed

Lin, Shao-Yu; Chooi, Yit-Heng; Solomon, Peter S

2018-05-03

To investigate effector gene regulation in the wheat pathogenic fungus Parastagonospora nodorum, the promoter and expression of Tox3 was characterised through a series of complementary approaches. Promoter deletion and DNase I footprinting experiments identified a 25 bp region in the Tox3 promoter as being required for transcription. Subsequent yeast one-hybrid analysis using the DNA sequence as bait identified that interacting partner as the C2H2 zinc finger transcription factor PnCon7, a putative master regulator of pathogenesis. Silencing of PnCon7 resulted in the down-regulation of Tox3 demonstrating that the transcription factor has a positive regulatory role on gene expression. Analysis of Tox3 expression in the PnCon7 silenced strains revealed a strong correlation with PnCon7 transcript levels, supportive of a direct regulatory role. Subsequent pathogenicity assays using PnCon7-silenced isolates revealed that the transcription factor was required for Tox3-mediated disease. The expression of two other necrotrophic effectors (ToxA and Tox1) was also affected but in a non-dose dependent manner suggesting that the regulatory role of PnCon7 on these genes was indirect. Collectively, these data have advanced our fundamental understanding of the Con7 master regulator of pathogenesis by demonstrating its positive regulatory role on the Tox3 effector in P. nodorum through direct interaction. This article is protected by copyright. All rights reserved. © 2018 John Wiley & Sons Ltd.

Pro/con a precessional geodynamo

NASA Astrophysics Data System (ADS)

Vanyo, J.

2003-04-01

The modest amount of research that exists on the ability, or lack of ability, of mantle precession to power a geodynamo developed mostly during the last half of the 1900s. Papers by Roberts and Stewartson (1965) and by Busse (1968) studied precession generally without a pro/con conclusion. Malkus in the late 1960s attempted to advance a positive role for precession through experiments and analysis. His experiments have survived criticism, but his analyses were discounted, especially by Rochester, Jacobs, Smylie, and Chong (1975) and by Loper (1975). Rochester, et al. critiqued existing analyses of precession, including those of Malkus, but did not reach a strong position either pro or con a precessional geodynamo. Loper argued emphatically that precession was not capable of powering the geodynamo. Explicit analyses that either critique or support Loper’s arguments have yet to appear in the literature. During the 1970s, Vanyo and associates studied energy dissipation during precession of satellite liquid fuels and its effect on satellite attitude stability. Engineers and scientists in every country that has launched satellites completed similar research. Some is published in the aerospace literature, more is available in company and government reports. Beginning in 1981, Vanyo and associates applied this knowledge to the very similar problem of energy dissipation and flow patterns in precessing mechanical models scaled geometrically and dynamically to the Earth’s liquid core. Energy experiments indicate massive amounts of mechanical energy are dissipated at the CMB, and flow experiments show complex motions within the boundary layer and axial flows with helicity throughout the interior. Analysis of Earth core precession also advanced, especially in several papers by Kerswell and by Tilgner in the late 1990s. Detail numerical models have yet to appear. Although progress in understanding the role of precession in Earth core motions has advanced, there remains a

Modelo de accesibilidad de conceptos matematicos aplicados en el curso de Astronomia Descriptiva para estudiantes con impedimentos visuales en la UPR

NASA Astrophysics Data System (ADS)

Isidro Villamizar, Gloria Maria

Este estudio utiliza metodologia de investigacion cualitativa, con el proposito de describir, analizar y evaluar los procesos de diseno y desarrollo de un modelo de accesibilidad que consiste en estrategias de ensenanza de las matematicas para estudiantes con impedimentos visuales matriculados en el curso de Astronomia Descriptiva en la UPR. Se utilizaron las siguientes estrategias para recopilar la informacion, 1) reflexiones de la investigadora en el proceso de diseno y desarrollo de las lecciones adaptadas, que se registraron en un diario reflexivo. 2) entrevista semiestructurada luego de haber trabajado las lecciones de aprendizaje adaptadas con los participantes. 3) observaciones y notas de la investigadora del trabajo de los participantes. Para obtener la informacion de los participantes se obtuvo los permisos institucionales necesarios; se seleccionaron los participantes y se validaron los instrumentos; se realizo el desarrollo de las lecciones adaptadas con los participantes; y finalmente, se analizo la informacion obtenida. El diseno de las lecciones de aprendizaje adaptadas se hizo siguiendo las recomendaciones curriculares de los temas de matematicas aplicados en el curso de Astronomia Descriptiva realizado por la investigadora durante su semestre de internado. El testimonio de las voces de los participantes se obtuvo del proceso de desarrollo de las lecciones de aprendizaje adaptadas de temas seleccionados de conceptos matematicos requeridos en el curso de Astronomia Descriptiva y de la entrevista semiestructurada con los participantes, luego de haber trabajado las lecciones de aprendizaje. Para el desarrollo de las lecciones de aprendizaje, se utilizaron materiales tactiles adaptados, materiales tactiles disenados y materiales disponibles comercialmente. Los textos de las lecciones se imprimieron en tinta y en Braille. Se exhorta a disenar y desarrollar estrategias de ensenanza accesibles, considerando como recursos para evaluar su efectividad a

Accurate macromolecular crystallographic refinement: incorporation of the linear scaling, semiempirical quantum-mechanics program DivCon into the PHENIX refinement package

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borbulevych, Oleg Y.; Plumley, Joshua A.; Martin, Roger I.

2014-05-01

Semiempirical quantum-chemical X-ray macromolecular refinement using the program DivCon integrated with PHENIX is described. Macromolecular crystallographic refinement relies on sometimes dubious stereochemical restraints and rudimentary energy functionals to ensure the correct geometry of the model of the macromolecule and any covalently bound ligand(s). The ligand stereochemical restraint file (CIF) requires a priori understanding of the ligand geometry within the active site, and creation of the CIF is often an error-prone process owing to the great variety of potential ligand chemistry and structure. Stereochemical restraints have been replaced with more robust functionals through the integration of the linear-scaling, semiempirical quantum-mechanics (SE-QM)more » program DivCon with the PHENIX X-ray refinement engine. The PHENIX/DivCon package has been thoroughly validated on a population of 50 protein–ligand Protein Data Bank (PDB) structures with a range of resolutions and chemistry. The PDB structures used for the validation were originally refined utilizing various refinement packages and were published within the past five years. PHENIX/DivCon does not utilize CIF(s), link restraints and other parameters for refinement and hence it does not make as many a priori assumptions about the model. Across the entire population, the method results in reasonable ligand geometries and low ligand strains, even when the original refinement exhibited difficulties, indicating that PHENIX/DivCon is applicable to both single-structure and high-throughput crystallography.« less

Multimodal navigated skull base tumor resection using image-based vascular and cranial nerve segmentation: A prospective pilot study

PubMed Central

Dolati, Parviz; Gokoglu, Abdulkerim; Eichberg, Daniel; Zamani, Amir; Golby, Alexandra; Al-Mefty, Ossama

2015-01-01

Background: Skull base tumors frequently encase or invade adjacent normal neurovascular structures. For this reason, optimal tumor resection with incomplete knowledge of patient anatomy remains a challenge. Methods: To determine the accuracy and utility of image-based preoperative segmentation in skull base tumor resections, we performed a prospective study. Ten patients with skull base tumors underwent preoperative 3T magnetic resonance imaging, which included thin section three-dimensional (3D) space T2, 3D time of flight, and magnetization-prepared rapid acquisition gradient echo sequences. Imaging sequences were loaded in the neuronavigation system for segmentation and preoperative planning. Five different neurovascular landmarks were identified in each case and measured for accuracy using the neuronavigation system. Each segmented neurovascular element was validated by manual placement of the navigation probe, and errors of localization were measured. Results: Strong correspondence between image-based segmentation and microscopic view was found at the surface of the tumor and tumor-normal brain interfaces in all cases. The accuracy of the measurements was 0.45 ± 0.21 mm (mean ± standard deviation). This information reassured the surgeon and prevented vascular injury intraoperatively. Preoperative segmentation of the related cranial nerves was possible in 80% of cases and helped the surgeon localize involved cranial nerves in all cases. Conclusion: Image-based preoperative vascular and neural element segmentation with 3D reconstruction is highly informative preoperatively and could increase the vigilance of neurosurgeons for preventing neurovascular injury during skull base surgeries. Additionally, the accuracy found in this study is superior to previously reported measurements. This novel preliminary study is encouraging for future validation with larger numbers of patients. PMID:26674155

Multimodal navigated skull base tumor resection using image-based vascular and cranial nerve segmentation: A prospective pilot study.

PubMed

Dolati, Parviz; Gokoglu, Abdulkerim; Eichberg, Daniel; Zamani, Amir; Golby, Alexandra; Al-Mefty, Ossama

2015-01-01

Skull base tumors frequently encase or invade adjacent normal neurovascular structures. For this reason, optimal tumor resection with incomplete knowledge of patient anatomy remains a challenge. To determine the accuracy and utility of image-based preoperative segmentation in skull base tumor resections, we performed a prospective study. Ten patients with skull base tumors underwent preoperative 3T magnetic resonance imaging, which included thin section three-dimensional (3D) space T2, 3D time of flight, and magnetization-prepared rapid acquisition gradient echo sequences. Imaging sequences were loaded in the neuronavigation system for segmentation and preoperative planning. Five different neurovascular landmarks were identified in each case and measured for accuracy using the neuronavigation system. Each segmented neurovascular element was validated by manual placement of the navigation probe, and errors of localization were measured. Strong correspondence between image-based segmentation and microscopic view was found at the surface of the tumor and tumor-normal brain interfaces in all cases. The accuracy of the measurements was 0.45 ± 0.21 mm (mean ± standard deviation). This information reassured the surgeon and prevented vascular injury intraoperatively. Preoperative segmentation of the related cranial nerves was possible in 80% of cases and helped the surgeon localize involved cranial nerves in all cases. Image-based preoperative vascular and neural element segmentation with 3D reconstruction is highly informative preoperatively and could increase the vigilance of neurosurgeons for preventing neurovascular injury during skull base surgeries. Additionally, the accuracy found in this study is superior to previously reported measurements. This novel preliminary study is encouraging for future validation with larger numbers of patients.

Topical Oxygen for Chronic Wounds: A PRO/CON Debate

PubMed Central

Mutluoglu, Mesut; Cakkalkurt, Aslican; Uzun, Gunalp; Aktas, Samil

2014-01-01

The role of oxygen in wound healing is universally accepted and does not require any further evidence; however the controversy as to whether oxygen delivery systems have the potential to improve wound healing remains to be concluded. Topical oxygen treatment (TOT) involves the delivery of 100% oxygen for a mean of 90 min, once a day at an atmospheric pressure slightly above 1 atm abs. The use of TOT gained increasing interest recently. The current manuscript will summarize the pros and cons of TOT in the view of the available literature. PMID:26199891

Non Invasive Biomedical Analysis - Breath Networking Session at PittCon 2011, Atlanta, Georgia

EPA Science Inventory

This was the second year that our breath colleagues organized a networking session at the Pittsburgh Conference and Exposition or ''PittCon'' (http://www.pincon.org/).This time it was called "Non-invasive Biomedical Analysis" to broaden the scope a bit, but the primary focus rema...

Application of Ultrasonic Bone Curette in Endoscopic Endonasal Skull Base Surgery: Technical Note

PubMed Central

Rastelli, Milton M.; Pinheiro-Neto, Carlos D.; Fernandez-Miranda, Juan C.; Wang, Eric W.; Snyderman, Carl H.; Gardner, Paul A.

2014-01-01

Background Endoscopic endonasal surgery (EES) of the skull base often requires extensive bone work in proximity to critical neurovascular structures. Objective To demonstrate the application of an ultrasonic bone curette during EES. Methods Ten patients with skull base lesions underwent EES from September 2011 to April 2012 at the University of Pittsburgh Medical Center. Most of the bone work was done with high-speed drill and rongeurs. The ultrasonic curette was used to remove specific structures. Results All the patients were submitted to fully endoscopic endonasal procedures and had critical bony structures removed with the ultrasonic bone curette. Two patients with degenerative spine diseases underwent odontoid process removal. Five patients with clival and petroclival tumors underwent posterior clinoid removal. Two patients with anterior fossa tumors underwent crista galli removal. One patient underwent unilateral optic nerve decompression. No mechanical or heat injury resulted from the ultrasonic curette. The surrounding neurovascular structures and soft tissue were preserved in all cases. Conclusion In selected EES, the ultrasonic bone curette was successfully used to remove loose pieces of bone in narrow corridors, adjacent to neurovascular structures, and it has advantages to high-speed drills in these specific situations. PMID:24719795

Brain vascular pericytes following ischemia have multipotential stem cell activity to differentiate into neural and vascular lineage cells.

PubMed

Nakagomi, Takayuki; Kubo, Shuji; Nakano-Doi, Akiko; Sakuma, Rika; Lu, Shan; Narita, Aya; Kawahara, Maiko; Taguchi, Akihiko; Matsuyama, Tomohiro

2015-06-01

Brain vascular pericytes (PCs) are a key component of the blood-brain barrier (BBB)/neurovascular unit, along with neural and endothelial cells. Besides their crucial role in maintaining the BBB, increasing evidence shows that PCs have multipotential stem cell activity. However, their multipotency has not been considered in the pathological brain, such as after an ischemic stroke. Here, we examined whether brain vascular PCs following ischemia (iPCs) have multipotential stem cell activity and differentiate into neural and vascular lineage cells to reconstruct the BBB/neurovascular unit. Using PCs extracted from ischemic regions (iPCs) from mouse brains and human brain PCs cultured under oxygen/glucose deprivation, we show that PCs developed stemness presumably through reprogramming. The iPCs revealed a complex phenotype of angioblasts, in addition to their original mesenchymal properties, and multidifferentiated into cells from both a neural and vascular lineage. These data indicate that under ischemic/hypoxic conditions, PCs can acquire multipotential stem cell activity and can differentiate into major components of the BBB/neurovascular unit. Thus, these findings support the novel concept that iPCs can contribute to both neurogenesis and vasculogenesis at the site of brain injuries. © 2015 AlphaMed Press.

Gradient Optimization for Analytic conTrols - GOAT

NASA Astrophysics Data System (ADS)

Assémat, Elie; Machnes, Shai; Tannor, David; Wilhelm-Mauch, Frank

Quantum optimal control becomes a necessary step in a number of studies in the quantum realm. Recent experimental advances showed that superconducting qubits can be controlled with an impressive accuracy. However, most of the standard optimal control algorithms are not designed to manage such high accuracy. To tackle this issue, a novel quantum optimal control algorithm have been introduced: the Gradient Optimization for Analytic conTrols (GOAT). It avoids the piecewise constant approximation of the control pulse used by standard algorithms. This allows an efficient implementation of very high accuracy optimization. It also includes a novel method to compute the gradient that provides many advantages, e.g. the absence of backpropagation or the natural route to optimize the robustness of the control pulses. This talk will present the GOAT algorithm and a few applications to transmons systems.

[Not Available].

PubMed

Chivu, Elena Cristina; Artero-Fullana, Ana; Alfonso García, Antonio; Sánchez Juan, Carlos

2016-07-19

Introducción: conociendo la elevada prevalencia de la desnutrición hospitalaria, se hace necesaria su detección precoz. Cuando, por diversos motivos, no es posible realizar una valoración completa del estado nutricional, se recomienda el empleo de herramientas validadas de cribado nutricional. Estas ayudarían a detectar de forma rápida a aquellos pacientes que necesiten de un tratamiento nutricional.Objetivos: determinar la prevalencia del riesgo de desnutrición, en el Hospital General Universitario de Valencia, empleando para ello la herramienta de cribado nutricional HEMAN y comprobar si la implementación de esta herramienta en la práctica clínica, sería lo más adecuado.Métodos: estudio transversal, realizado sobre una muestra de 1.099 pacientes ingresados en un hospital terciario. A todos ellos se les realizó el cribado nutricional HEMAN a las 24-48 horas del ingreso. Las variables cualitativas se compararon mediante Chi-cuadrado, y las cuantitativas mediante el test t de Student.Resultados: la prevalencia del riesgo de desnutrición fue del 33,5%. Los pacientes que resultaron positivos en el cribado (HEMAN ≥ 3), tenían mayor edad que los pacientes normonutridos, referían pérdidas de peso entre el 5-10%, el 55,2% disminuyó su ingesta a menos del 50% de la habitual. Además, ingresaron con patologías consideradas de leves a moderadas. La utilización del método HEMAN como herramienta de cribado, resultó ser práctica y efectiva, y ayudó a disminuir el tiempo empleado con cada paciente encuestado evaluado.Conclusiones: se detectó una elevada prevalencia de riesgo de desnutrición entre los pacientes evaluados, por lo tanto se hace imprescindible la utilización de métodos de cribado nutricional en la rutina diaria del hospital, para ello recomendamos especialmente la utilización del método HEMAN.

Segundo Catálogo Estelar del Hemisferio Sur con Astrolabio Fotoeléctrico PAII

NASA Astrophysics Data System (ADS)

Manrique, W. T.; Podestá, R. C.; Alonso, E.; Actis, E. V.; Pacheco, A. M.; Bustos, G.; Lizhi, L.; Zezhi, W.; Fanmiao, Z.; Hongqi, W.; Perdomo, R.

Recordamos que entre el Observatorio Astronómico ``Félix Aguilar'', el Observatorio Astronómico de Beijing y el Observatorio Astronómico de La Plata, se ha convenido en desarrollar un Proyecto de Investigación conjunto, para la observación sistemática de estrellas en el Hemisferio Sur, con el objeto de la elaboración de un Catálogo Estelar Global utilizando un Astrolabio Fotoeléctrico PAII del Observatorio de Beijing, que ha sido usado con éxito en la República de China. En este trabajo se presenta el Segundo Catálogo Estelar del Hemisferio Sur, derivado de las observaciones realizadas con el PAII instalado en el OAFA, durante el períiodo Febrero de 1992 a Marzo de 1997. En este lapso se han observado mas de 400000 pasajes estelares, obteniéndose las correcciones Δ α y Δ δ de 5241 estrellas del FK4, FK5, FK5 Ext., SRS, CAMC y GC. Las precisiones medias son del orden de ± 3,2 ms en ascensión recta y ±0."057 en declinación. Rango de magnitudes : 2,0 a 11,5 Rango de declinaciones : -3o a -60o Epoca Media : 1994.9 Se analizan los residuos en función de la magnitud y tipo espectral, correcciones de grupo y frecuencia de distribución Δ α y Δ δ.

Expanding applications, accuracy, and interpretation of laser speckle contrast imaging of cerebral blood flow

PubMed Central

Kazmi, S M Shams; Richards, Lisa M; Schrandt, Christian J; Davis, Mitchell A; Dunn, Andrew K

2015-01-01

Laser speckle contrast imaging (LSCI) provides a rapid characterization of cortical flow dynamics for functional monitoring of the microcirculation. The technique stems from interactions of laser light with moving particles. These interactions encode the encountered Doppler phenomena within a random interference pattern imaged in widefield, known as laser speckle. Studies of neurovascular function and coupling with LSCI have benefited from the real-time characterization of functional dynamics in the laboratory setting through quantification of perfusion dynamics. While the technique has largely been relegated to acute small animal imaging, its scalability is being assessed and characterized for both chronic and clinical neurovascular imaging. PMID:25944593

Review of the mechanisms and therapeutic avenues for retinal and choroidal vascular dysfunctions in retinopathy of prematurity.

PubMed

Rivera, José Carlos; Madaan, Ankush; Zhou, Tianwei Ellen; Chemtob, Sylvain

2016-12-01

Retinopathy of prematurity (ROP) is a multifactorial disease and the main cause of visual impairment and blindness in premature neonates. The inner retina has been considered the primary region affected in ROP, but choroidal vascular degeneration and progressive outer retinal dysfunctions have also been observed. This review focuses on observations regarding neurovascular dysfunctions in both the inner and outer immature retina, the mechanisms and the neuronal-derived factors implicated in the development of ROP, as well potential therapeutic avenues for this disorder. Alterations in the neurovascular integrity of the inner and outer retina contribute to the development of ROP. ©2016 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Descompresión microvascular en espasmo hemifacial: Reporte de 13 casos y revisión de la literatura

PubMed Central

Campero, Alvaro; Herreros, Isabel Cuervo-Arango; Barrenechea, Ignacio; Andjel, Germán; Ajler, Pablo; Rhoton, Albert

2016-01-01

Objetivo: El propósito del presente trabajo es presentar los resultados de 13 pacientes con diagnóstico de espasmo hemifacial (EHF), en los cuales se realizó una descompresión microvascular (DMV). Material y Método: Desde Junio de 2005 a Mayo de 2014, 13 pacientes con diagnóstico de EHF fueron intervenidos quirúrgicamente, realizando una DMV. Se evaluó: edad, sexo, tiempo de evolución de la sintomatología, hallazgos intraoperatorios y resultados postoperatorios. Resultados: De los 13 pacientes intervenidos, 7 fueron mujeres y 6 varones. La media de edad fue de 53 años. El tiempo medio entre el inicio de la sintomatología y la intervención quirúrgica osciló entre 3 y 9 años. En todos los casos el EHF era típico, uno de ellos con neuralgia trigeminal concomitante, observándose en todos compresión neurovascular intraoperatoria. Por orden decreciente de frecuencia la causa de la compresión fue arteria cerebelosa anteroinferior, arteria cerebelosa posteroinferior, arteria dolicomega basilar y arteria dolicomega vertebral. El seguimiento postoperatorio fue en promedio de 24 meses. El 62% presentó desaparición postquirúrgica inmediata de la sintomatología preoperatoria, el 30% desaparición tras un período de 3 semanas a 2 meses (8% con mejoría parcial), y en el 8% no hubo mejoría. En cuanto a las complicaciones postoperatorias: 3 pacientes presentaron paresia facial II-III en la escala de House-Brackman (se recuperaron en un período de 6 meses), y 1 paciente presentó fístula de líquido cefalorraquídeo. Ninguno de los pacientes de la serie presentaron hipoacusia transitorio o permanente. Conclusión: La DMV como tratamiento del EHF es un procedimiento efectivo y seguro, que permite la resolución completa de la patología en la mayoría de los casos. PMID:27127708

Wilderness for science: pros and cons of using wilderness areas for biological research

Treesearch

Diana L. Six; Paul Alaback; Robert A. Winfree; Delia Snyder; Anne Hagele

2000-01-01

Research is one of the intended purposes of wilderness. The Wilderness Act states that “wilderness may contain ecological, geological, or other features of scientific, educational, scenic, or historical value.” This session specifically focuses on the pros and cons of conducting research in wilderness.

ConsDock: A new program for the consensus analysis of protein-ligand interactions.

PubMed

Paul, Nicodème; Rognan, Didier

2002-06-01

Protein-based virtual screening of chemical libraries is a powerful technique for identifying new molecules that may interact with a macromolecular target of interest. Because of docking and scoring limitations, it is more difficult to apply as a lead optimization method because it requires that the docking/scoring tool is able to propose as few solutions as possible and all of them with a very good accuracy for both the protein-bound orientation and the conformation of the ligand. In the present study, we present a consensus docking approach (ConsDock) that takes advantage of three widely used docking tools (Dock, FlexX, and Gold). The consensus analysis of all possible poses generated by several docking tools is performed sequentially in four steps: (i) hierarchical clustering of all poses generated by a docking tool into families represented by a leader; (ii) definition of all consensus pairs from leaders generated by different docking programs; (iii) clustering of consensus pairs into classes, represented by a mean structure; and (iv) ranking the different means starting from the most populated class of consensus pairs. When applied to a test set of 100 protein-ligand complexes from the Protein Data Bank, ConsDock significantly outperforms single docking with respect to the docking accuracy of the top-ranked pose. In 60% of the cases investigated here, ConsDock was able to rank as top solution a pose within 2 A RMSD of the X-ray structure. It can be applied as a postprocessing filter to either single- or multiple-docking programs to prioritize three-dimensional guided lead optimization from the most likely docking solution. Copyright 2002 Wiley-Liss, Inc.

Change in Brooklyn and Queens: How New York?s Reforming the Energy Vision Program and Con Edison Are Reshaping Electric Distribution Planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coddington, Michael; Sciano, Damian; Fuller, Jason

In response to this tremendous growth in both population and electricity demand, Con Edison estimates that its cost to expand the “traditional” Brooklyn-Queens grid will be in the neighborhood of US$1.2 billion—a relatively high number, even for New York City and Con Edison. The complexity of the city’s underground electrical system along with the difficulties of construction in a highly congested urban environment with infrastructure both above and below ground mean that the costs for transmission, substations, and secondary networks are significantly higher than those of a typical electric utility. The New York State Public Service Commission (PSC) is inmore » the process revising its approach to acquiring and serving energy throughout the state of New York, and traditional expansion for this rather costly project was not likely to be approved. Instead, the PSC asked Con Edison to evaluate numerous alternatives. The PSC and Con Edison are now considering and adopting strategies that include renewable energy generation, demand response (DR), battery energy storage systems, fuel-cell distributed generation, combined heat and power, volt-volt ampere reactive (VAR) optimization (VVO), and a host of other innovative solutions that would both reduce electricity demand and transform how and when Con Edison’s consumers use electricity.« less

Proyecto para la medición sistemática de seeing en CASLEO

NASA Astrophysics Data System (ADS)

Fernández Lajus, E.; Forte, J. C.

La calidad del seeing astronómico es ciertamente uno de los parámetros mas importantes que caracterizan el sitio de un observatorio. Por tanto se desea determinar si el alto valor de seeing observado con el telescopio de 2.15 m se debe a efectos internos y/o del entorno a la cupula o si se debe simplemente al seeing propio del lugar. El actual mecanismo de refrigeración del espejo primario del 2.15, parece haber mejorado notablemente la calidad del seeing. Sin embargo se hace necesario saber hasta que punto el valor del seeing puede ser mejorado. La primera etapa del proyecto consistió en la puesta a punto del telescopio emplazado para este propósito y la adquisición de las primeras medidas tentativas de seeing.

Development of poly(lactic-co-glycolic) acid nanoparticles-embedded hyaluronic acid-ceramide-based nanostructure for tumor-targeted drug delivery.

PubMed

Park, Ju-Hwan; Lee, Jae-Young; Termsarasab, Ubonvan; Yoon, In-Soo; Ko, Seung-Hak; Shim, Jae-Seong; Cho, Hyun-Jong; Kim, Dae-Duk

2014-10-01

A hyaluronic acid-ceramide (HACE) nanostructure embedded with docetaxel (DCT)-loaded poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles (NPs) was fabricated for tumor-targeted drug delivery. NPs with a narrow size distribution and negative zeta potential were prepared by embedding DCT-loaded PLGA NPs into a HACE nanostructure (DCT/PLGA/HACE). DCT-loaded PLGA and DCT/PLGA/HACE NPs were characterized by solid-state techniques, including Fourier-transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD). A sustained drug release pattern from the NPs developed was observed and negligible cytotoxicity was seen in NIH3T3 cells (normal fibroblast, CD44 receptor negative) and MDA-MB-231 cells (breast cancer cells, CD44 receptor positive). PLGA/HACE NPs containing coumarin 6, used as a fluorescent dye, exhibited improved cellular uptake efficiency, based on the HA-CD44 receptor interaction, compared to plain PLGA NPs. Cyanine 5.5 (Cy5.5)-labeled PLGA/HACE NPs were injected intravenously into a MDA-MB-231 tumor xenograft mouse model and demonstrated enhanced tumor targetability, compared with Cy5.5-PLGA NPs, according to a near-infrared fluorescence (NIRF) imaging study. Considering these experimental results, the DCT/PLGA/HACE NPs developed may be useful as a tumor-targeted drug delivery system. Copyright © 2014 Elsevier B.V. All rights reserved.

Neogene sequence stratigraphy, Nam Con Son Basin, offshore Vietnam

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMillen, K.J.; Do Van Luu; Lee, E.K.

1996-12-31

An integrated well log, biostratigraphic, and seismic stratigraphic study of Miocene to Recent deltaic sediments deposited in the Nam Con Son Basin offshore from southern Vietnam shows the influence of eustacy and tectonics on sequence development. Sediments consist of Oligocene non-marine rift-basin fill (Cau Formation), early to middle Miocene tide-dominated delta plain to delta front sediments (TB 1.5 to TB 2.5, Due and Thong Formations), and late Miocene to Recent marine shelf sediments (TB. 2.6 to TB 3.1 0, Mang Cau, Nam Con Son, and Bien Dong Formations). Eustacy controlled the timing of key surfaces and sand distribution in themore » tectonically-quiet early Miocene. Tectonic effects on middle to late Miocene sequence development consist of thick transgressive systems tracts due to basin-wide subsidence and transgression, sand distribution in the basin center, and carbonate sedimentation on isolated fault blocks within the basin. Third-order sequence boundaries (SB) are identified by spore peaks, sand stacking patterns, and channel incision. In the basin center, widespread shale beds with coal occur above sequence boundaries followed by transgressive sandstone units. These TST sandstones merge toward the basin margin where they lie on older HST sandstones. Maximum flooding surfaces (MFS) have abundant marine microfossils and mangrove pollen, a change in sand stacking pattern, and often a strong seismic reflection with downlap. Fourth-order genetic-type sequences are also interpreted. The MFS is the easiest marker to identify and correlate on well logs. Fourth-order SB occur within these genetic units but are harder to identify and correlate.« less

Neogene sequence stratigraphy, Nam Con Son Basin, offshore Vietnam

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMillen, K.J.; Do Van Luu; Lee, E.K.

1996-01-01

An integrated well log, biostratigraphic, and seismic stratigraphic study of Miocene to Recent deltaic sediments deposited in the Nam Con Son Basin offshore from southern Vietnam shows the influence of eustacy and tectonics on sequence development. Sediments consist of Oligocene non-marine rift-basin fill (Cau Formation), early to middle Miocene tide-dominated delta plain to delta front sediments (TB 1.5 to TB 2.5, Due and Thong Formations), and late Miocene to Recent marine shelf sediments (TB. 2.6 to TB 3.1 0, Mang Cau, Nam Con Son, and Bien Dong Formations). Eustacy controlled the timing of key surfaces and sand distribution in themore » tectonically-quiet early Miocene. Tectonic effects on middle to late Miocene sequence development consist of thick transgressive systems tracts due to basin-wide subsidence and transgression, sand distribution in the basin center, and carbonate sedimentation on isolated fault blocks within the basin. Third-order sequence boundaries (SB) are identified by spore peaks, sand stacking patterns, and channel incision. In the basin center, widespread shale beds with coal occur above sequence boundaries followed by transgressive sandstone units. These TST sandstones merge toward the basin margin where they lie on older HST sandstones. Maximum flooding surfaces (MFS) have abundant marine microfossils and mangrove pollen, a change in sand stacking pattern, and often a strong seismic reflection with downlap. Fourth-order genetic-type sequences are also interpreted. The MFS is the easiest marker to identify and correlate on well logs. Fourth-order SB occur within these genetic units but are harder to identify and correlate.« less

Are You Ready to Go Digital?: The Pros and Cons of Electronic Portfolio Development

ERIC Educational Resources Information Center

Heath, Marilyn

2005-01-01

There is an increasing need for educators to have professional portfolios, which are considered to be authentic tools for evaluating the knowledge, skill, beliefs and attitudes of prospective educators. Electronic portfolios are gaining in popularity and their relative pros and cons are examined.

RETOS EN LA INTERVENCIÓN CON ADOLESCENTES PUERTORRIQUEÑOS/AS QUE MANIFIESTAN COMPORTAMIENTO SUICIDA*

PubMed Central

Vélez, Yovanska Duarté; Dávila, Paloma Torres; Hernández, Samariz Laboy

2015-01-01

Presentamos un estudio de caso de una adolescente puertorriqueña con comportamiento suicida. Esta comenzó una Terapia Socio Cognitivo-Conductual para el Comportamiento Suicida (TSCC-CS) de tipo ambulatorio luego de una hospitalización por intento suicida. La TSCC-CS incorpora una perspectiva ecológica y de desarrollo a la terapia cognitivo-conductual. Inicialmente mostró baja autoestima y severos síntomas depresivos y de ansiedad. Al finalizar el tratamiento, manifestó un cambio significativo en su sintomatología clínica y evidenció una mejoría en sus destrezas de manejo. No presentó ideas suicidas durante meses previos, ni durante el seguimiento. El análisis de este caso permitió realizar cambios en el protocolo de tratamiento, particularmente en las sesiones de familia y de comunicación con el fin de aumentar la viabilidad del tratamiento. PMID:26702337

Use of a GnRH vaccine, GonaCon, for prevention and treatment of adrenocortical disease (ACD) in domestic ferrets.

PubMed

Miller, Lowell A; Fagerstone, Kathleen A; Wagner, Robert A; Finkler, Mark

2013-09-23

Adrenocortical disease (ACD) is a common problem in surgically sterilized, middle-aged to old ferrets (Mustela putorius furo). The adrenal tissues of these ferrets develop hyperplasia, adenomas, or adenocarcinomas, which produce steroid hormones including estradiol, 17-hydroxyprogesterone, and androstenedione. Major clinical signs attributable to overproduction of these hormones are alopecia (hair loss) in both sexes and a swollen vulva in females. Pruritus, muscle atrophy, hind limb weakness, and sexual activity or aggression are also observed in both sexes. Males can develop prostatic cysts, prostatitis, and urethral obstruction. ACD is thought to be linked to continuous and increased LH secretion, due to lack of gonadal hormone feedback in neutered ferrets. This continuous elevated LH acts on adrenal cortex LH receptors, resulting in adrenal hyperplasia or adrenal tumor. This study investigated whether the immunocontraceptive vaccine GonaCon, a GnRH vaccine developed to reduce the fertility of wildlife species and the spread of disease, could prevent or delay onset of ACD and treat alopecia in ferrets with existing ACD. Results showed that GonaCon provided relief from ACD by causing production of antibodies to GnRH, probably suppressing production and/or release of LH. Treatment caused many ACD symptoms to disappear, allowing the ferrets to return to a normal life. The study also found that the probability of developing ACD was significantly reduced in ferrets treated with GonaCon when young (1-3 years old) compared to untreated control animals. GonaCon caused injection site reaction in some animals when administered as an intramuscular injection but caused few side effects when administered subcutaneously. Both intramuscular and subcutaneous vaccination resulted in similar levels of GnRH antibody titers. Subcutaneous vaccination with GonaCon is thus recommended to prevent the onset of ACD and as a possible treatment for ACD-signs in domestic ferrets. Published

Anabaena sp. strain PCC 7120 conR contains a LytR-CpsA-Psr domain, is developmentally regulated, and is essential for diazotrophic growth and heterocyst morphogenesis.

PubMed

Mella-Herrera, Rodrigo A; Neunuebel, M Ramona; Golden, James W

2011-03-01

The conR (all0187) gene of the filamentous cyanobacterium Anabaena (Nostoc) sp. strain PCC 7120 is predicted to be part of a family of proteins that contain the LytR-CpsA-Psr domain associated with septum formation and cell wall maintenance. The conR gene was originally misannotated as a transcription regulator. Northern RNA blot analysis showed that conR expression was upregulated 8 h after nitrogen step-down. Fluorescence microscopy of a P(conR)-gfp reporter strain revealed increased GFP fluorescence in proheterocysts and heterocysts beginning 9 h after nitrogen step-down. Insertional inactivation of conR caused a septum-formation defect of vegetative cells grown in nitrate-containing medium. In nitrate-free medium, mutant filaments formed abnormally long heterocysts and were defective for diazotrophic growth. Septum formation between heterocysts and adjacent vegetative cells was abnormal, often with one or both poles of the heterocysts appearing partially open. In a conR mutant, expression of nifH was delayed after nitrogen step-down and nitrogenase activity was approximately 70 % of wild-type activity, indicating that heterocysts of the conR mutant strain are partially functional. We hypothesize that the diazotrophic growth defect is caused by an inability of the heterocysts to transport fixed nitrogen to the neighbouring vegetative cells.

"Con todo mi corazón": Mentoring Latinas in Educational Leadership Doctoral Programs

ERIC Educational Resources Information Center

Rodríguez, Mariela A.

2016-01-01

Personal narrative essays were used to analyze the experiences of four Latina doctoral students who completed their first year in an educational leadership doctoral program in a Hispanic-Serving Institution (HSI) in the southwestern U.S. Four themes emerged from their "testimonios" 1) "Con todo el corazón"; 2) "Somos como…

Contaminación por mercurio de leche materna de madres lactantes de municipios de Antioquia con explotación minera de oro.

PubMed

Molina, Carlos Federico; Arango, Catalina María; Sepúlveda, Hernán

2018-05-01

Introducción. La leche materna es esencial para el desarrollo del ser humano, pero puede contener sustancias tóxicas provenientes de la contaminación ambiental, especialmente en las áreas mineras.Objetivo. Determinar la prevalencia de la contaminación con mercurio de la leche materna de mujeres lactantes residentes en los municipios con explotación minera de oro.Materiales y métodos. Se hizo un estudio transversal de 150 madres lactantes de cuatro municipios mineros de Antioquia (El Bagre, Segovia, Remedios y Zaragoza), a quienes se les hizo una encuesta sobre factores sociodemográficos, ocupacionales y ambientales relacionados con el mercurio, y se les tomaron muestras de leche materna, de orina y de cabello. Se calculó el promedio de la concentración de mercurio y las prevalencias municipales de contaminación.Resultados. El promedio de la concentración de mercurio en la leche materna fue de 2,5 (± desviación estándar 9,2) μg/L. La prevalencia de muestras de leche materna con niveles altos de mercurio fue de 11,7 %.Conclusión. En este estudio se evidencia un grave problema en las regiones mineras auríferas de Antioquia por el efecto de la contaminación con mercurio en sectores de la población más vulnerable.

The Con Edison Emergency Child Care Plan for Management Employees: Summary Plan Description.

ERIC Educational Resources Information Center

Consolidated Edison Co., Brooklyn, NY.

This summary plan description offers guidelines for participation in a pilot program that provides short-term emergency care for children of Con Edison managers who are under 13 years old. The plan offers professional, in-home child care that can be used when usual arrangements have collapsed. The summary plan description addresses the following…

Pros & Cons of Using Blackboard Collaborate for Blended Learning on Students' Learning Outcomes

ERIC Educational Resources Information Center

Hamad, Mona M.

2017-01-01

Blackboard Collaborate was introduced to King Khalid University recently in the last decade; instructors and students were trained to use it in an effective way. The objective of this study is to find pros and cons of using Blackboard Collaborate for Blended Learning and its effect on students' learning outcomes. The researcher used the…

Arginase in Retinopathy

PubMed Central

Narayanan, S. Priya; Rojas, Modesto; Suwanpradid, Jutamas; Toque, Haroldo A.; Caldwell, R. William; Caldwell, Ruth B.

2013-01-01

Ischemic retinopathies, such as diabetic retinopathy (DR), retinopathy of prematurity and retinal vein occlusion are a major cause of blindness in developed nations worldwide. Each of these conditions is associated with early neurovascular dysfunction. However, conventional therapies target clinically significant macula edema or neovascularization, which occur much later. Intraocular injections of anti-VEGF show promise in reducing retinal edema, but the effects are usually transient and the need for repeated injections increases the risk of intraocular infection. Laser photocoagulation can control pathological neovascularization, but may impair vision and in some patients the retinopathy continues to progress. Moreover, neither treatment targets early stage disease or promotes repair. This review examines the potential role of the ureahydrolase enzyme arginase as a therapeutic target for the treatment of ischemic retinopathy. Arginase metabolizes L-arginine to form proline, polyamines and glutamate. Excessive arginase activity reduces the L-arginine supply for nitric oxide synthase (NOS), causing it to become uncoupled and produce superoxide and less NO. Superoxide and NO react and form the toxic oxidant peroxynitrite. The catabolic products of polyamine oxidation and glutamate can induce more oxidative stress and DNA damage, both of which can cause cellular injury. Studies indicate that neurovascular injury during retinopathy is associated with increased arginase expression/activity, decreased NO, polyamine oxidation, formation of superoxide and peroxynitrite and dysfunction and injury of both vascular and neural cells. Furthermore, data indicate that the cytosolic isoform arginase I (AI) is involved in hyperglycemia-induced dysfunction and injury of vascular endothelial cells whereas the mitochondrial isoform arginase II (AII) is involved in neurovascular dysfunction and death following hyperoxia exposure. Thus, we postulate that activation of the arginase

Aspergilosis cervical con diseminación al sistema nervioso central. Presentación de un caso y revisión de bibliografía

PubMed Central

Vergara, Guillermo Enrique; Roura, Natalia; del Castillo, Marcelo; Mora, Andrea; Alcorta, Santiago Condomi; Mormandi, Rubén; Cervio, Andrés; Salvat, Jorge

2015-01-01

Introducción: la Aspergilosis Invasiva (AI) del Sistema Nervioso Central (SNC) es infrecuente y ocurre generalmente en pacientes inmunocomprometidos. Puede presentarse con cuadros de meningitis, aneurismas micóticos, infartos o abscesos. Es una infección con pronóstico reservado y puede afectar el SNC de forma primaria o secundaria a partir de un foco que se disemina por vía hematógena. Presentamos el caso de un paciente con AI con invasión primaria a nivel óseo y diseminación posterior al cerebro. Caso clínico: Paciente masculino de 25 años con diagnóstico de leucemia linfática aguda en tratamiento quimioterápico que presentó neumonitis por metotrexate por lo que inicia tratamiento con corticoides. Posteriormente agregó cervicalgia y con el diagnóstico de osteomielitis cervical se realiza punción bajo tomografía computada (TC) sin aislarse gérmenes. Se colocó Halo Vest e inició tratamiento antibiótico empírico. Posteriormente presentó afasia de expresión secundaria a lesión frontal izquierda. Se realizó evacuación de absceso cerebral aislando A. fumigatus. El tratamiento antibiótico específico posterior permitió una buena respuesta clínica y radiológica. Conclusión: La presencia de lesiones en el SNC de pacientes inmunocomprometidos debe incluir a las micosis como diagnóstico diferencial. La evacuación quirúrgica permite llegar rápidamente al diagnóstico mejorando la respuesta posterior al tratamiento antibiótico. Para evaluar la respuesta terapéutica y posibles recaídas se debe realizar un seguimiento periódico clínico radiológico. Palabras clave: Aspergilosis cerebral; Aspergilosis cervical; Aspergilosis invasiva; Voriconazol. PMID:26600985

Structure, stratigraphy and petroleum geology of the south east Nam Con Son Basin, offshore Vietnam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fraser, A.J.; Matthews, S.J.; Lowe, S.

1996-12-31

Recent exploration of the south east Nam Con Son Basin, offshore Vietnam, by BP in alliance with Statoil has involved acquisition of new seismic and well data. These new data have allowed re-evaluation of the tectono-stratigraphic development and petroleum geology, and have provided additional constraints on the regional tectonic evolution. The offshore Vietnamese basins have evolved in response to the complex relative motions of Indochina, Peninsular Malaysia, Borneo and the South China Sea during the Cenozoic. On the regional scale these motions have been accommodated by strike-slip fault development, rifting and contraction. In the Nam Con Son Basin these motionsmore » have interacted in different ways from the Palaeogene to recent. Two rifting episodes are recognized; a Palaeogene phase dominated by E-W trending extensional faults, and a Miocene phase dominated by N-S to NE-SW trending faults. The structural evolution is complicated by a pulse of mild contraction during the Middle Miocene. The sedimentary fill of the basin evolves from continental fluvio-lacustrine in the Palaeogene through to fully marine following the second phase of rifting in the Miocene. This pulsed structural and stratigraphic evolution has resulted in basinwide deposition of source, reservoir and seal facies, and produced a variety of potential trapping styles. This paper describes the hydrocarbon habitat of the south east Nam Con Son Basin within the context of the regional tectono-stratigraphic model.« less

Structure, stratigraphy and petroleum geology of the south east Nam Con Son Basin, offshore Vietnam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fraser, A.J.; Matthews, S.J.; Lowe, S.

1996-01-01

Recent exploration of the south east Nam Con Son Basin, offshore Vietnam, by BP in alliance with Statoil has involved acquisition of new seismic and well data. These new data have allowed re-evaluation of the tectono-stratigraphic development and petroleum geology, and have provided additional constraints on the regional tectonic evolution. The offshore Vietnamese basins have evolved in response to the complex relative motions of Indochina, Peninsular Malaysia, Borneo and the South China Sea during the Cenozoic. On the regional scale these motions have been accommodated by strike-slip fault development, rifting and contraction. In the Nam Con Son Basin these motionsmore » have interacted in different ways from the Palaeogene to recent. Two rifting episodes are recognized; a Palaeogene phase dominated by E-W trending extensional faults, and a Miocene phase dominated by N-S to NE-SW trending faults. The structural evolution is complicated by a pulse of mild contraction during the Middle Miocene. The sedimentary fill of the basin evolves from continental fluvio-lacustrine in the Palaeogene through to fully marine following the second phase of rifting in the Miocene. This pulsed structural and stratigraphic evolution has resulted in basinwide deposition of source, reservoir and seal facies, and produced a variety of potential trapping styles. This paper describes the hydrocarbon habitat of the south east Nam Con Son Basin within the context of the regional tectono-stratigraphic model.« less

Comportamiento del Helio en estrellas químicamente peculiares

NASA Astrophysics Data System (ADS)

Malaroda, S. M.; López García, Z.; Leone, F.; Catalano, F.

Las estrellas químicamente peculiares (CP) se caracterizan por tener deficiencias y sobreabundancias de algunos elementos químicos de hasta 106 veces la abundancia solar. Además presentan variaciones en las líneas espectrales. Se piensa que ello se debe a que los campos magnéticos presentes en este tipo de estrellas son principalmente dipolares, con un eje de simetría diferente del eje de rotación. La distribución de los elementos sobreabundantes y deficientes no es homogénea sobre la superficie estelar y las variaciones observadas serían una consecuencia directa de la rotación estelar. Entre los elementos con abundancia anómala se encuentra el Helio, cuyas líneas tienen intensidades que no son consistentes con una abundancia normal, que no puede ser determinada del modo usual, o sea, considerando una atmósfera con composición solar. Con el fin de determinar la abundancia de este elemento, se inició un estudio de estrellas anómalas de Helio, Hew y He strong. Además se determinarán las abundancias de otros elementos anómalos como ser el Si, Cr, Mg, Mn y Fe. Las mismas se determinan del modo tradicional, o sea: a) medida de los anchos equivalentes de las líneas de los distintos elementos analizados; b) adopción de la temperatura efectiva, gravedad y abundancia del Helio; c) cálculo del modelo de atmósfera d) comparación con las observaciones y reinicio de un proceso iterativo hasta lograr un acuerdo entre todos los parámetros analizados. Las observaciones se llevaron a cabo en el Complejo Astronómico El Leoncito. Se observaron setenta y ocho estrellas anómalas de Helio. En este momento se está procediendo a calcular las abundancias correspondientes a los distintos elementos químicos. Para ello se hace uso de los modelos de Kurucz, ATLAS9. Los cálculos NLTE de las líneas de Helio se llevan a cabo con el programa MULTI y se compararán con los realizados con el programa WIDTH9 de Kurucz (LTE), con el objeto de resaltar la importancia de

NASA KSC/AFRL Reusable Booster System (RBS) Concept of Operations (ConOps)

NASA Technical Reports Server (NTRS)

Zeno, Dnany; Mosteller, Ted; McCleskey, Carey; Jhnson, Robert; Hopkins, Jason; Miller, Thomas

2010-01-01

This slide presentation reviews the study and findings of the study on the Concept of Operations (ConOps) for Reusable Booster System (RBS) centering on rapid turnaround and launch of a two-stage partially reusable payload delivery system (i.e., 8 hours between launches). The study was to develop rapid ground processing (aircraft like concepts) and identify areas for follow-on study, technology needs, and proof-of-concept demonstrations.

Pros and cons of phage therapy

PubMed Central

Loc-Carrillo, Catherine

2011-01-01

Many publications list advantages and disadvantages associated with phage therapy, which is the use of bacterial viruses to combat populations of nuisance or pathogenic bacteria. The goal of this commentary is to discuss many of those issues in a single location. In terms of “Pros,” for example, phages can be bactericidal, can increase in number over the course of treatment, tend to only minimally disrupt normal flora, are equally effective against antibiotic-sensitive and antibiotic-resistant bacteria, often are easily discovered, seem to be capable of disrupting bacterial biofilms, and can have low inherent toxicities. In addition to these assets, we consider aspects of phage therapy that can contribute to its safety, economics, or convenience, but in ways that are perhaps less essential to the phage potential to combat bacteria. For example, autonomous phage transfer between animals during veterinary application could provide convenience or economic advantages by decreasing the need for repeated phage application, but is not necessarily crucial to therapeutic success. We also consider possible disadvantages to phage use as antibacterial agents. These “Cons,” however, tend to be relatively minor. PMID:22334867

Genes del receptor variable beta de células T en células circulantes de pacientes con lupus eritematoso generalizado y sus familiares sanos.

PubMed

Jakez-Ocampo, Juan; Paulín-Vera, Carmen María; Rivadeneyra-Espinoza, Liliana; Gómez-Martín, Diana; Carrillo-Maravilla, Eduardo; Lima, Guadalupe; Vargas-Rojas, María Inés; Pérez-Romano, Beatriz; Calva-Cevenini, Gabriella; García-Carrasco, Mario; Ruiz-Argüelles, Alejandro; Llorente, Luis

Se investigó la proporción de la expresión génica del receptor variable beta de células T (Vβ TCR) en linfocitos periféricos CD3+ en pacientes con lupus eritematoso generalizado (LEG) familiar y no familiar. El repertorio de Vβ TCR se estudió en 14 familias que presentaban más de un miembro con LEG. El uso de Vβ TCR en pacientes con LEG (n = 27) se comparó con el de los miembros sanos de estas familias (n = 47), con 37 pacientes con LEG esporádico y con 15 controles sanos. La expresión del repertorio de Vβ TCR se estudió por citometría de flujo multiparamétrica utilizando un arreglo de 24 diferentes anticuerpos monoclonales específicos de genes familiares para Vβ TCR. Se encontró el mismo perfil de expresión en las comparaciones entre los casos de LEG esporádico y familiar, así como en los consanguíneos sanos de las familias multicasos, que incluía una expresión incrementada de Vβ 5.2, Vβ 11 y Vβ 16, y una menor expresión de Vβ 3, Vβ4, Vβ 7.1 y Vβ 7. De manera interesante, solo Vβ 17 se expresó de modo diferente entre casos familiares y esporádicos de LEG. Igualmente, la expresión incrementada de Vβ 9 fue el distintivo entre los casos de LEG familiar (casos y consanguíneos sanos) y los controles sanos. Estos resultados refuerzan la noción de que el perfil final del repertorio Vβ TCR observado en LEG familiar y no familiar parece surgir de la interacción de factores genéticos, ambientales e inmunorreguladores, además de que pueden explicar las alteraciones inmunitarias que se observan en los consanguíneos sanos de pacientes con LEG. Copyright: © 2018 SecretarÍa de Salud

PubMed

Escandón-Nagel, Neli

2016-11-29

Introducción: si bien el Trastorno por Atracón es un trastorno de la conducta alimentaria que  no se da exclusivamente en personas obesas, es más común en este grupo que en sujetos con normopeso, sin embargo no todas las personas con malnutrición por exceso presentan Trastorno por Atracón. Objetivo: identificar el conocimiento actual respecto a las diferencias y semejanzas existentes entre personas con malnutrición por exceso con y sin Trastorno por Atracón.Método: para lograr el objetivo anterior, se realizó una revisión de artículos científicos en torno al tema.Resultados: primero se analizó la comorbilidad psicopatológica en obesidad y después se detectaron similitudes y diferencias entre los grupos de interés, tanto en sintomatología general, como así también en sintomatología de la conducta alimentaria. Además, se identificaron algunos aspectos controversiales, en que existe evidencia contradictoria respecto a la comparación intergrupal.Conclusión: de esta revisión se concluye que en el estudio de la obesidad se hace necesario conocer en mayor profundidad las características del subgrupo de pacientes que además presenta Trastorno por Atracón,  ya que estas personas poseen características distintivas cuyo conocimiento permitirá ofrecer tratamientos integrales más adecuados a las necesidades de los pacientes, lo que posibilitará, en consecuencia, diseñar intervenciones más eficaces.

[Modern tribology in total hip arthroplasty: pros and cons].

PubMed

Gómez-García, F

2014-01-01

The wear products and adverse reactions that occur on bearing surfaces represent one of the greatest challenges in prosthetic replacements, as the latter experience increasing demands due to the large number of young and older adult patients that have a long life expectancy and remarkable activity. The purpose of this review is to analyze the pros and cons of the new advances in the bearing components of the articular surfaces of current total hip arthroplasties. We also discuss the strategies used historically, their problems, results and the surgeon's role in prescribing the tribologic couple that best fits each patient's needs. We conclude with practical recommendations for the prescription and management of the latest articular couples for total hip arthroplasty.

ConMap: Investigating New Computer-Based Approaches to Assessing Conceptual Knowledge Structure in Physics.

ERIC Educational Resources Information Center

Beatty, Ian D.

There is a growing consensus among educational researchers that traditional problem-based assessments are not effective tools for diagnosing a student's knowledge state and for guiding pedagogical intervention, and that new tools grounded in the results of cognitive science research are needed. The ConMap ("Conceptual Mapping") project, described…

Basolateral amygdala volume and cell numbers in major depressive disorder: a postmortem stereological study.

PubMed

Rubinow, Marisa J; Mahajan, Gouri; May, Warren; Overholser, James C; Jurjus, George J; Dieter, Lesa; Herbst, Nicole; Steffens, David C; Miguel-Hidalgo, Jose J; Rajkowska, Grazyna; Stockmeier, Craig A

2016-01-01

Functional imaging studies consistently report abnormal amygdala activity in major depressive disorder (MDD). Neuroanatomical correlates are less clear: imaging studies have produced mixed results on amygdala volume, and postmortem neuroanatomic studies have only examined cell densities in portions of the amygdala or its subregions in MDD. Here, we present a stereological analysis of the volume of, and the total number of, neurons, glia, and neurovascular (pericyte and endothelial) cells in the basolateral amygdala in MDD. Postmortem tissues from 13 subjects with MDD and 10 controls were examined. Sections (~15/subject) taken throughout the rostral-caudal extent of the basolateral amygdala (BLA) were stained for Nissl substance and utilized for stereological estimation of volume and cell numbers. Results indicate that depressed subjects had a larger lateral nucleus than controls and a greater number of total BLA neurovascular cells than controls. There were no differences in the number or density of neurons or glia between depressed and control subjects. These findings present a more detailed picture of BLA cellular anatomy in depression than has previously been available. Further studies are needed to determine whether the greater number of neurovascular cells in depressed subjects may be related to increased amygdala activity in depression.

Superior and anterior inferior cerebellar arteries and their relationship with cerebello-pontine angle cranial nerves revisited in the light of cranial cephalometric indexes: a cadaveric study.

PubMed

Habibi, Zohreh; Meybodi, Ali Tayebi; Maleki, Farid; Tabatabai, Seyed

2011-01-01

The aim was to clarify the anatomical features of the superior and anterior inferior cerebellar arteries in relation to the trigeminal nerve and acoustic-facial complex and to the bony structures of the skull in a sample of male Iranian cadavers. Bilateral dissections, calvariectomy, and brain evacuation were performed on 31 adult human fresh brains and skull bases to assess the neurovascular associations, and skull base morphometry. Equations were defined to estimate posterior fossa volume and the relationships between bony and neurovascular elements. Eight SCAs were duplicated from origin. There were 9 cases of SCA-trigeminal contacts, which were at the root entry zone in 7. Mean distance from the origin of AICA to the vertebrobasilar junction was 11.80 mm, while 79% of AICAs originated from the lower half of the BA. This was significantly associated with "posterior fossa funneling" and "basilar narrowing" indexes. In most cases AICA crossed the acoustic-facial complex and coursed between neural bundles (48.3%). The AICA reached or entered the internal acoustic canal in 22.6% of cases and was medial to porous in 77.4%. We documented anatomical variations of the superior and anterior inferior cerebellar arteries along with some cephalometric equations with relevant neurovascular anatomy in Iranian cadavers.

Acetazolamide-induced vasodilation does not inhibit the visually evoked flow response

PubMed Central

Yonai, Yaniv; Boms, Neta; Molnar, Sandor; Rosengarten, Bernhard; Bornstein, Natan M; Csiba, Laszlo; Olah, Laszlo

2010-01-01

Different methods are used to assess the vasodilator ability of cerebral blood vessels; however, the exact mechanism of cerebral vasodilation, induced by different stimuli, is not entirely known. Our aim was to investigate whether the potent vasodilator agent, acetazolamide (AZ), inhibits the neurovascular coupling, which also requires vasodilation. Therefore, visually evoked flow parameters were examined by transcranial Doppler in ten healthy subjects before and after AZ administration. Pulsatility index and peak systolic flow velocity changes, evoked by visual stimulus, were recorded in the posterior cerebral arteries before and after intravenous administration of 15 mg/kg AZ. Repeated-measures ANOVA did not show significant group main effect between the visually evoked relative flow velocity time courses before and after AZ provocation (P=0.43). Visual stimulation induced significant increase of relative flow velocity and decrease of pulsatility index not only before but also at the maximal effect of AZ. These results suggest that maximal cerebral vasodilation cannot be determined by the clinically accepted dose of AZ (15 mg/kg) and prove that neurovascular coupling remains preserved despite AZ-induced vasodilation. Our observation indicates independent regulation of vasodilation during neurovascular coupling, allowing the adaptation of cerebral blood flow according to neuronal activity even if other processes require significant vasodilation. PMID:19809468

Plantar Fascia Release Through a Single Lateral Incision in the Operative Management of a Cavovarus Foot: A Cadaver Model Analysis of the Operative Technique.

PubMed

Kiskaddon, Eric M; Meeks, Brett D; Roberts, Joseph G; Laughlin, Richard T

2018-04-04

Plantar fascia release and calcaneal slide osteotomy are often components of the surgical management for cavovarus deformities of the foot. In this setting, plantar fascia release has traditionally been performed through an incision over the medial calcaneal tuberosity, and the calcaneal osteotomy through a lateral incision. Two separate incisions can potentially increase the operative time and morbidity. The purpose of the present study was threefold: to describe the operative technique, use cadaveric dissection to analyze whether a full release of the plantar fascia was possible through the lateral incision, and examine the proximity of the medial neurovascular structures to both the plantar fascia release and calcaneal slide osteotomy when performed together. In our cadaveric dissections, we found that full release of the plantar fascia is possible through the lateral incision with no obvious damage to the medial neurovascular structures. We also found that the calcaneal branch of the tibial nerve reliably crossed the osteotomy in all specimens. We have concluded that both the plantar fascia release and the calcaneal osteotomy can be safely performed through a lateral incision, if care is taken when completing the calcaneal osteotomy to ensure that the medial neurovascular structures remain uninjured. Copyright © 2017 The American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Protective Effects of Astaxanthin on ConA-Induced Autoimmune Hepatitis by the JNK/p-JNK Pathway-Mediated Inhibition of Autophagy and Apoptosis

PubMed Central

Liu, Tong; Wang, Junshan; Dai, Weiqi; Wang, Fan; Zheng, Yuanyuan; Chen, Kan; Li, Sainan; Abudumijiti, Huerxidan; Zhou, Zheng; Wang, Jianrong; Lu, Wenxia; Zhu, Rong; Yang, Jing; Zhang, Huawei; Yin, Qin; Wang, Chengfen; Zhou, Yuqing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

2015-01-01

Objective Astaxanthin, a potent antioxidant, exhibits a wide range of biological activities, including antioxidant, atherosclerosis and antitumor activities. However, its effect on concanavalin A (ConA)-induced autoimmune hepatitis remains unclear. The aim of this study was to investigate the protective effects of astaxanthin on ConA-induced hepatitis in mice, and to elucidate the mechanisms of regulation. Materials and Methods Autoimmune hepatitis was induced in in Balb/C mice using ConA (25 mg/kg), and astaxanthin was orally administered daily at two doses (20 mg/kg and 40 mg/kg) for 14 days before ConA injection. Levels of serum liver enzymes and the histopathology of inflammatory cytokines and other maker proteins were determined at three time points (2, 8 and 24 h). Primary hepatocytes were pretreated with astaxanthin (80 μM) in vitro 24 h before stimulation with TNF-α (10 ng/ml). The apoptosis rate and related protein expression were determined 24 h after the administration of TNF-α. Results Astaxanthin attenuated serum liver enzymes and pathological damage by reducing the release of inflammatory factors. It performed anti-apoptotic effects via the descending phosphorylation of Bcl-2 through the down-regulation of the JNK/p-JNK pathway. Conclusion This research firstly expounded that astaxanthin reduced immune liver injury in ConA-induced autoimmune hepatitis. The mode of action appears to be downregulation of JNK/p-JNK-mediated apoptosis and autophagy. PMID:25761053

Integrated Concentration in Science (iCons): Undergraduate Education Through Interdisciplinary, Team-Based, Real-World Problem Solving

NASA Astrophysics Data System (ADS)

Tuominen, Mark

2013-03-01

Attitude, Skills, Knowledge (ASK) - In this order, these are fundamental characteristics of scientific innovators. Through first-hand practice in using science to unpack and solve complex real-world problems, students can become self-motivated scientific leaders. This presentation describes the pedagogy of a recently developed interdisciplinary undergraduate science education program at the University of Massachusetts Amherst focused on addressing global challenges with scientific solutions. Integrated Concentration in Science (iCons) is an overarching concentration program that supplements the curricula provided within each student's chosen major. iCons is a platform for students to perform student-led research in interdisciplinary collaborative teams. With a schedule of one course per year over four years, the cohort of students move through case studies, analysis of real-world problems, development of potential solutions, integrative communication, laboratory practice, and capstone research projects. In this presentation, a track emphasizing renewable energy science is used to illustrate the iCons pedagogical methods. This includes discussion of a third-year laboratory course in renewable energy that is educationally scaffolded: beginning with a boot camp in laboratory techniques and culminating with student-designed research projects. Among other objectives, this course emphasizes the practice of using reflection and redesign, as a means of generating better solutions and embedding learning for the long term. This work is supported in part by NSF grant DUE-1140805.

75 FR 51081 - Center for Scientific Review; Notice of Closed Meetings

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

...- 0684, [email protected] . Name of Committee: Brain Disorders and Clinical Neuroscience Integrated Review Group, Brain Injury and Neurovascular Pathologies Study Section. Date: September 27-28, 2010. Time...

Protective Effects of Calpain Inhibition on Neurovascular Unit Injury through Downregulating Nuclear Factor-κB-related Inflammation during Traumatic Brain Injury in Mice

PubMed Central

Tao, Xiao-Gang; Shi, Jing-Hua; Hao, Shu-Yu; Chen, Xue-Tao; Liu, Bai-Yun

2017-01-01

Background: In addition to neurons, all components of the neurovascular unit (NVU), such as glial, endothelial, and basal membranes, are destroyed during traumatic brain injury (TBI). Previous studies have shown that excessive stimulation of calpain is crucial for cerebral injury after traumatic insult. The objective of this study was to investigate whether calpain activation participated in NVU disruption and edema formation in a mouse model of controlled cortical impact (CCI). Methods: One hundred and eight mice were divided into three groups: the sham group, the control group, and the MDL28170 group. MDL28170 (20 mg/kg), an efficient calpain inhibitor, was administered intraperitoneally at 5 min, 3 h, and 6 h after experimental CCI. We then measured neurobehavioral deficits, calpain activity, inflammatory mediator levels, blood–brain barrier (BBB) disruption, and NVU deficits using electron microscopy and histopathological analysis at 6 h and 24 h after CCI. Results: The MDL28170 treatment significantly reduced the extent of both cerebral contusion (MDL28170 vs. vehicle group, 16.90 ± 1.01 mm3 and 17.20 ± 1.17 mm3 vs. 9.30 ± 1.05 mm3 and 9.90 ± 1.17 mm3, both P < 0.001) and edema (MDL28170 vs. vehicle group, 80.76 ± 1.25% and 82.00 ± 1.84% vs. 82.55 ± 1.32% and 83.64 ± 1.25%, both P < 0.05), improved neurological scores (MDL28170 vs. vehicle group, 7.50 ± 0.45 and 6.33 ± 0.38 vs. 12.33 ± 0.48 and 11.67 ± 0.48, both P < 0.001), and attenuated NVU damage resulting (including tight junction (TJ), basement membrane, BBB, and neuron) from CCI at 6 h and 24 h. Moreover, MDL28170 markedly downregulated nuclear factor-κB-related inflammation (tumor necrosis factor-α [TNF-α]: MDL28170 vs. vehicle group, 1.15 ± 0.07 and 1.62 ± 0.08 vs. 1.59 ± 0.10 and 2.18 ± 0.10, both P < 0.001; inducible nitric oxide synthase: MDL28170 vs. vehicle group, 4.51 ± 0.23 vs. 6.23 ± 0.12, P < 0.001 at 24 h; intracellular adhesion molecule-1: MDL28170 vs. vehicle group

Accurate macromolecular crystallographic refinement: incorporation of the linear scaling, semiempirical quantum-mechanics program DivCon into the PHENIX refinement package.

PubMed

Borbulevych, Oleg Y; Plumley, Joshua A; Martin, Roger I; Merz, Kenneth M; Westerhoff, Lance M

2014-05-01

Macromolecular crystallographic refinement relies on sometimes dubious stereochemical restraints and rudimentary energy functionals to ensure the correct geometry of the model of the macromolecule and any covalently bound ligand(s). The ligand stereochemical restraint file (CIF) requires a priori understanding of the ligand geometry within the active site, and creation of the CIF is often an error-prone process owing to the great variety of potential ligand chemistry and structure. Stereochemical restraints have been replaced with more robust functionals through the integration of the linear-scaling, semiempirical quantum-mechanics (SE-QM) program DivCon with the PHENIX X-ray refinement engine. The PHENIX/DivCon package has been thoroughly validated on a population of 50 protein-ligand Protein Data Bank (PDB) structures with a range of resolutions and chemistry. The PDB structures used for the validation were originally refined utilizing various refinement packages and were published within the past five years. PHENIX/DivCon does not utilize CIF(s), link restraints and other parameters for refinement and hence it does not make as many a priori assumptions about the model. Across the entire population, the method results in reasonable ligand geometries and low ligand strains, even when the original refinement exhibited difficulties, indicating that PHENIX/DivCon is applicable to both single-structure and high-throughput crystallography.

[In Process Citation].

PubMed

López Siguero, Juan Pedro

2016-03-25

La prevalencia de obesidad y de diabetes tipo 2 ha aumentado enormemente en las últimas décadas hasta convertirse en una epidemia amenazante. El listado de factores de riesgo es amplio, pero lo encabeza el cambio del estilo de vida (alimentación y actividad física) que constituye, además, la herramienta preventiva más importante. El trabajo de Caravalí-Meza y cols. en este número de la revista hace hincapié en el consumo de bebidas azucaradas y su relación con la obesidad. Sus autores concluyen que el consumo de azúcares refinados de las bebidas en adolescentes mexicanos, conlleva un riesgo de incremento del perímetro de la cintura y, en el caso de mantenerse, también del índice de masa corporal.

ProCon - PROteomics CONversion tool.

PubMed

Mayer, Gerhard; Stephan, Christian; Meyer, Helmut E; Kohl, Michael; Marcus, Katrin; Eisenacher, Martin

2015-11-03

With the growing amount of experimental data produced in proteomics experiments and the requirements/recommendations of journals in the proteomics field to publicly make available data described in papers, a need for long-term storage of proteomics data in public repositories arises. For such an upload one needs proteomics data in a standardized format. Therefore, it is desirable, that the proprietary vendor's software will integrate in the future such an export functionality using the standard formats for proteomics results defined by the HUPO-PSI group. Currently not all search engines and analysis tools support these standard formats. In the meantime there is a need to provide user-friendly free-to-use conversion tools that can convert the data into such standard formats in order to support wet-lab scientists in creating proteomics data files ready for upload into the public repositories. ProCon is such a conversion tool written in Java for conversion of proteomics identification data into standard formats mzIdentML and Pride XML. It allows the conversion of Sequest™/Comet .out files, of search results from the popular and often used ProteomeDiscoverer® 1.x (x=versions 1.1 to1.4) software and search results stored in the LIMS systems ProteinScape® 1.3 and 2.1 into mzIdentML and PRIDE XML. This article is part of a Special Issue entitled: Computational Proteomics. Copyright © 2015. Published by Elsevier B.V.

Desarrollo de la Escala sobre el Estigma Relacionado con el VIH/SIDA para Profesionales de la Salud mediante el uso de métodos mixtos123

PubMed Central

Varas-Díaz, Nelson; Neilands, Torsten B.; Guilamo-Ramos, Vincent; Cintrón Bou, Francheska N.

2009-01-01

El estigma relacionado con el VIH/SIDA continúa siendo un obstáculo para la prevención primaria y secundaria del VIH. Las consecuencias para las personas que viven con la enfermedad han sido muy documentadas y continúan siendo una gran preocupación para las personas que proveen servicios de salud y para aquellas que investigan el tema. Estas consecuencias son preocupantes cuando el estigma emana de profesionales de la salud porque se puede limitar el acceso a los servicios. Uno de los principales obstáculos para la investigación del estigma relacionado con el VIH en Puerto Rico es la falta de instrumentos cuantitativos para evaluar las manifestaciones del estigma entre profesionales de la salud. El objetivo principal de este estudio fue desarrollar y probar las propiedades psicométricas de una escala sobre el estigma relacionado con el VIH/SIDA culturalmente apropiada para personas que proveen servicios de salud puertorriqueñas y desarrollar una versión corta de la escala que pudiera usarse en escenarios clínicos con tiempo limitado. El instrumento desarrollado estuvo basado en evidencia cualitativa recopilada entre profesionales y estudiantes de profesiones de la salud puertorriqueños/as (n=80) y administrado a una muestra de 421 profesionales de la salud en adiestramiento. La escala contenía 12 dimensiones del estigma relacionado con el VIH/SIDA. El análisis cuantitativo corroboró 11 de ellas, teniendo como resultado un instrumento con validez y confiabilidad satisfactoria. Estas dimensiones, a su vez, fueron subcomponentes de un factor de estigma general superior. PMID:20333258

Fragilidad y su asociación con mortalidad, hospitalizaciones y dependencia funcional en mexicanos de 60 años o más

PubMed Central

de León González, Enrique Díaz; Pérez, Héctor Eloy Tamez; Hermosillo, Hugo Gutiérrez; Rodríguez, Javier Armando Cedillo; Torres, Gabriela

2016-01-01

Fundamento y objetivo Determinar la asociación entre fragilidad y mortalidad, dependencia funcional, caídas y hospitalizaciones en el Estudio Nacional de Salud y Envejecimiento en México (ENASEM). Sujetos y métodos Estudio prospectivo poblacional en México en el que se seleccionaron sujetos de 60 años o más, que fueron evaluados en las variables de fragilidad durante la primera vuelta del estudio en el año 2001 y que incluyó: dificultad para levantarse de una silla después de haber estado sentado(a) durante largo tiempo, pérdida de peso de 5 kilogramos o más en los últimos dos años y falta de energía. Los sujetos fueron catalogados como robustos, prefrágiles y frágiles cuando tenían cero, una o dos de las características anteriores, respectivamente. La mortalidad, hospitalizaciones, caídas y dependencia funcional fueron evaluadas en la segunda vuelta del estudio en el año 2003. Se calculó el riesgo relativo para cada una de las complicaciones, así como análisis multivariado con regresión de Cox para el caso de mortalidad y regresión logística para el resto. Resultados Los estados de prefragilidad y fragilidad se asociaron independientemente con mortalidad, con índices de riesgo ajustados de 1,61 (intervalo de confianza del 95% [IC 95%] 1,01-2,55) y 1,94 (IC 95% 1,20-3,13), respectivamente. Sólo el estado de fragilidad se asoció independientemente con hospitalización y dependencia funcional, con una razón de momios ajustada de 1,53 (IC 95% 1,13-2,07) y 3,07 (IC 95% 1,76-5,34), respectivamente. No hubo asociación entre los estados de prefragilidad y fragilidad con caídas. Conclusión El estado de fragilidad se asocia independientemente con mortalidad, hospitalizaciones y disfuncionalidad en actividades básicas de la vida diaria en los siguientes dos años en población mexicana. PMID:21612803

La interacción de estrellas WN con el medio circundante

NASA Astrophysics Data System (ADS)

Arnal, M.; Cappa, C.; Rizzo, J. R.; Cichovolski, S.

Se presentan resultados preliminares de un estudio de la distribución del hidrógeno neutro en los alrededores de estrellas WR de la serie del nitrógeno. Los datos observacionales de la línea de 21 cm provienen de un relevamineto de baja resolución angular (36'), así como de observaciones de resolución angular intermedia (9') tomadas con el radiotelescopio de Effelsberg. Este análisis ha permitido detectar cavidades y envolturas de H I en expansión vinculadas a las estrellas que componen la muestra.

Impacto metabólico e inflamatorio de una comida rica en grasas saturadas y su relación con la obesidad abdominal.

PubMed

Alayón, Alicia Norma; Rivadeneira, Ana Patricia; Herrera, Carlos; Guzmán, Heidy; Arellano, Dioneris; Echeverri, Isabella

2018-05-01

Introducción. La etapa posprandial se asocia con el incremento de marcadores relacionados con el riesgo cardiovascular, cuya intensidad depende del estado metabólico.Objetivo. Determinar el impacto de la ingestión de una comida rica en grasas saturadas sobre el perfil metabólico e inflamatorio y su relación con la obesidad abdominal.Materiales y métodos. Se hizo un ensayo clínico en 42 individuos (21 con obesidad abdominal). Se midieron, en sangre, la glucosa, la insulina, el perfil lipídico, la proteína C reactiva, los lipopolisacáridos y la interleucina 6, en ayunas y después de la ingestión.Resultados. Además de la obesidad, se registró la presencia de resistencia a la insulina y de niveles elevados de triacilglicéridos y proteína C reactiva en ayunas. Asimismo, se detectaron niveles posprandiales más elevados de glucosa, insulina y triacilglicéridos. La interleucina 6 disminuyó en el grupo de personas sin obesidad y los lipopolisacáridos aumentaron en ambos grupos.Conclusión. La ingestión de una comida rica en grasas saturadas produjo un mayor impacto en las variables glucémicas en el grupo con obesidad y, aunque afectó de forma similar los lípidos en ambos grupos, el incremento de triacilglicéridos fue mayor en presencia de una concentración basal elevada y promovió el aumento de lipopolisacáridos. El estado inflamatorio basal y posprandial afectó en mayor medida al grupo con obesidad. El momento posprandial reflejó el estado más frecuente de los individuos en un día normal y permitió evidenciar la capacidad de respuesta metabólica frente a la ingestión de alimentos, así como los estados tempranos de riesgo metabólico.

A con-focal setup for micro-XRF experiments using diamond anvil cells

NASA Astrophysics Data System (ADS)

Wilke, Max; Rickers, Karen; Vincze, Laszlo; Schmidt, Christian; Borchert, Manuela; Pascarelli, Sakura

2010-05-01

In this contribution we introduce an experimental setup to perform con-focal micro X-ray fluorescence measurements in situ in samples at high temperatures and pressures in diamond anvil cells (DAC) (e.g. Schmidt et al. 2007). The con-focal arrangement is used to suppress the background in X-ray fluorescence (XRF) spectra that stems from elastic and inelastic scattering of the diamond anvils. The setup is based on a focusing optic in the incident beam that reaches a spot of 5-10 μm and a focusing poly-capillary in front of an energy-dispersive solid-state detector. The detector poly-capillary is designed to work at a very long working distance of 50 mm in order to collect the radiation from the center of the DAC at 90° to the incident beam. The probing volume is defined by the two foci and has a size of ca. 300 μm at 8 keV and 150 μm at 19 keV as measured by scans through thin metal foils. Comparison of XRF spectra acquired with a usual detector collimator and spectra recorded with the detector capillary shows a strong suppression of XRF signal generated outside the probed volume, i.e. XRF from the gasket material and signal from elastic and Compton scattering by the diamond anvils. The ratio of the Zr K-alpha fluorescence peak to the peak of the Compton scattering changes from 0.5 (collimator) to 1.26 (detector capillary) for a ca. 1000 ppm Zr standard solution and an incident beam energy of 20 keV. For a standard solution containing ca. 1000 ppm Hf, the ratio of the L-alpha to the Compton signal increases to 6 using the detector capillary and an incident beam energy of 9.7 keV. Thus, the con-focal setup substantially improves the fluorescence to background ratio. This will result in higher sensitivities for dilute elements in the sample chamber of the DAC. Furthermore, the possibilities of interference of the sample's signal with signal from the sample environment are greatly reduced. In a broader sense, the setup can also be applied to other confined samples

Caffe con Troll: Shallow Ideas to Speed Up Deep Learning

PubMed Central

Hadjis, Stefan; Abuzaid, Firas; Zhang, Ce; Ré, Christopher

2016-01-01

We present Caffe con Troll (CcT), a fully compatible end-to-end version of the popular framework Caffe with rebuilt internals. We built CcT to examine the performance characteristics of training and deploying general-purpose convolutional neural networks across different hardware architectures. We find that, by employing standard batching optimizations for CPU training, we achieve a 4.5× throughput improvement over Caffe on popular networks like CaffeNet. Moreover, with these improvements, the end-to-end training time for CNNs is directly proportional to the FLOPS delivered by the CPU, which enables us to efficiently train hybrid CPU-GPU systems for CNNs. PMID:27314106

Caffe con Troll: Shallow Ideas to Speed Up Deep Learning.

PubMed

Hadjis, Stefan; Abuzaid, Firas; Zhang, Ce; Ré, Christopher

2015-01-01

We present Caffe con Troll (CcT), a fully compatible end-to-end version of the popular framework Caffe with rebuilt internals. We built CcT to examine the performance characteristics of training and deploying general-purpose convolutional neural networks across different hardware architectures. We find that, by employing standard batching optimizations for CPU training, we achieve a 4.5× throughput improvement over Caffe on popular networks like CaffeNet. Moreover, with these improvements, the end-to-end training time for CNNs is directly proportional to the FLOPS delivered by the CPU, which enables us to efficiently train hybrid CPU-GPU systems for CNNs.

Moderator's view: High-volume plasma exchange: pro, con and consensus.

PubMed

Kaplan, Andre A

2017-09-01

I have been asked to comment on the pro and con opinions regarding high-volume plasma exchange. The authors of both positions have provided cogent arguments and a reasonable approach to choosing the exchange volume for any given therapeutic plasma exchange. The major issue of relevance in this discussion is the nature of the toxins targeted for removal. These parameters include molecular weight, the apparent volume of distribution, the degree of protein binding, the biologic and chemical half-life, and the severity and rapidity of its toxicity. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

Nano anti-cancer drugs: pros and cons and future perspectives.

PubMed

Ali, Imran

2011-02-01

For last one decade, scientists are working for developing nano anti-cancer drugs with claim of ideal ones due to their targeted chemotherapic nature. These drugs have many beneficial properties such as targeted drug delivery and gene therapy modalities with minimum side effects. This article describes pros and cons and future perspectives of nano anti-cancer drugs. Efforts have been made to address importance, special features, toxicities (general, blood identities, immune system and environmental) and future perspectives of nano anti-cancer drugs. It was concluded that nano anti-cancer drugs may be magic bullet drugs for cancer treatment leading to bright future of the whole world.

Balancing Ethical Pros and Cons of Stem Cell Derived Gametes.

PubMed

Segers, Seppe; Mertes, Heidi; de Wert, Guido; Dondorp, Wybo; Pennings, Guido

2017-07-01

In this review we aim to provide an overview of the most important ethical pros and cons of stem cell derived gametes (SCD-gametes), as a contribution to the debate about reproductive tissue engineering. Derivation of gametes from stem cells holds promising applications both for research and for clinical use in assisted reproduction. We explore the ethical issues connected to gametes derived from embryonic stem cells (both patient specific and non-patient specific) as well as those related to gametes derived from induced pluripotent stem cells. The technology of SCD-gametes raises moral concerns of how reproductive autonomy relates to issues of embryo destruction, safety, access, and applications beyond clinical infertility.

What are the pros and cons of electronically monitoring inhaler use in asthma? A multistakeholder perspective.

PubMed

Howard, Sam; Lang, Alexandra; Sharples, Sarah; Shaw, Dominick

2016-01-01

Electronic monitoring devices (EMDs) are the optimal method for collecting objective data on inhaler use in asthma. Recent research has investigated the attitudes of patients with asthma towards these devices. However, no research to date has formally considered the opinions of stakeholders and decision-makers in asthma care. These individuals have important clinical requirements that need to be taken into account if EMDs are to be successfully provisioned, making collecting their opinions on the key barriers facing these devices a valuable process. Three rounds of surveys in a Delphi format were used to assess the most important pros and cons of EMDs for asthma care in a sample of 31 stakeholders which included healthcare professionals and members of clinical commissioning groups. The respondents identified 29 pros and 32 cons. Pros that were rated as most important included new visual evidence to aid clinical discussions with a patient and an increase in patient involvement and motivation. The cons that were rated as most important included a need for more clinical evidence of the effectiveness of EMDs, as well as better clarity over who has responsibilities in managing, interpreting and discussing data with a patient. The research provides a guide for EMD developers by highlighting where these devices may provide the most benefit as well as prioritising the key issues that need addressing if they are to be used effectively in everyday asthma care.

What are the pros and cons of electronically monitoring inhaler use in asthma? A multistakeholder perspective

PubMed Central

Howard, Sam; Lang, Alexandra; Sharples, Sarah; Shaw, Dominick

2016-01-01

Introduction Electronic monitoring devices (EMDs) are the optimal method for collecting objective data on inhaler use in asthma. Recent research has investigated the attitudes of patients with asthma towards these devices. However, no research to date has formally considered the opinions of stakeholders and decision-makers in asthma care. These individuals have important clinical requirements that need to be taken into account if EMDs are to be successfully provisioned, making collecting their opinions on the key barriers facing these devices a valuable process. Methods Three rounds of surveys in a Delphi format were used to assess the most important pros and cons of EMDs for asthma care in a sample of 31 stakeholders which included healthcare professionals and members of clinical commissioning groups. Results The respondents identified 29 pros and 32 cons. Pros that were rated as most important included new visual evidence to aid clinical discussions with a patient and an increase in patient involvement and motivation. The cons that were rated as most important included a need for more clinical evidence of the effectiveness of EMDs, as well as better clarity over who has responsibilities in managing, interpreting and discussing data with a patient. Conclusions The research provides a guide for EMD developers by highlighting where these devices may provide the most benefit as well as prioritising the key issues that need addressing if they are to be used effectively in everyday asthma care. PMID:27933181

Magnetic Phase Transition in Ion-Irradiated Ultrathin CoN Films via Magneto-Optic Faraday Effect.

PubMed

Su, Chiung-Wu; Chang, Yen-Chu; Chang, Sheng-Chi

2013-11-15

The magnetic properties of 1 nm thick in-plane anisotropic Co ultrathin film on ZnO(0001) were investigated through successive 500 eV nitrogen-ion sputtering. Magneto-optical Faraday effects were used to observe the evolution of the ion-irradiated sample in longitudinal and perpendicular magnetic fields. The ferromagnetic phase of the initial in-plane anisotropic fcc β-Co phase transformation to β-Co(N) phase was terminated at paramagnetic CoN x phase. In-plane anisotropy with weak out-of-plane anisotropy of the Co/ZnO sample was initially observed in the as-grown condition. In the sputtering process, the N⁺ ions induced simultaneous sputtering and doping. An abrupt spin reorientation behavior from in-plane to out-of-plane was found under prolonged sputtering condition. The existence of perpendicular anisotropy measured from the out-of-plane Faraday effect may be attributed to the co-existence of residual β-Co and Co₄N exchange bonding force by the gradual depletion of Co-N thickness.

Mandated Mental Health Insurance: A Complex Case of Pros and Cons. Human Resources Series.

ERIC Educational Resources Information Center

Paterson, Andrea

1986-01-01

The pros and cons of state laws mandating mental health insurance are discussed in this report. The history of a 1985 Supreme Court case which held that states could mandate mental health benefits introduces the report. In an overview of the issue, the long-standing argument between the insurance industry and the mental health establishment is…

Social stress induces neurovascular pathology promoting depression

PubMed Central

Menard, Caroline; Pfau, Madeline L.; Hodes, Georgia E.; Kana, Veronika; Wang, Victoria X.; Bouchard, Sylvain; Takahashi, Aki; Flanigan, Meghan E.; Aleyasin, Hossein; LeClair, Katherine B.; Janssen, William G.; Labonté, Benoit; Parise, Eric M.; Lorsch, Zachary S.; Golden, Sam A.; Heshmati, Mitra; Tamminga, Carol; Turecki, Gustavo; Campbell, Matthew; Fayad, Zahi; Tang, Cheuk Ying; Merad, Miriam; Russo, Scott J.

2017-01-01

Studies suggest that heightened peripheral inflammation contributes to the pathogenesis of major depressive disorder. We investigated the effect of chronic social defeat stress, a mouse model of depression, on blood-brain barrier (BBB) permeability and infiltration of peripheral immune signals. We found reduced expression of endothelial cell tight junction protein claudin-5 (cldn5) and abnormal blood vessel morphology in nucleus accumbens (NAc) of stress-susceptible but not resilient mice. CLDN5 expression was also decreased in NAc of depressed patients. Cldn5 down-regulation was sufficient to induce depression-like behaviors following subthreshold social stress while chronic antidepressant treatment rescued cldn5 loss and promoted resilience. Reduced BBB integrity in NAc of stress-susceptible or AAV-shRNA-cldn5-injected mice caused infiltration of peripheral cytokine interleukin-6 (IL-6) into brain parenchyma and subsequent expression of depression-like behaviors. These findings suggest that chronic social stress alters BBB integrity through loss of tight junction protein cldn5, promoting peripheral IL-6 passage across the BBB and depression. PMID:29184215

Neurovascular contributions to migraine: Moving beyond vasodilation.

PubMed

Jacobs, Blaine; Dussor, Gregory

2016-12-03

Migraine is the third most common disease worldwide, the most common neurological disorder, and one of the most common pain conditions. Despite its prevalence, the basic physiology and underlying mechanisms contributing to the development of migraine are still poorly understood and development of new therapeutic targets is long overdue. Until recently, the major contributing pathophysiological event thought to initiate migraine was cerebral and meningeal arterial vasodilation. However, the role of vasodilation in migraine is unclear and recent findings challenge its necessity. While vasodilation itself may not contribute to migraine, it remains possible that vessels play a role in migraine pathophysiology in the absence of vasodilation. Blood vessels consist of a variety of cell types that both release and respond to numerous mediators including growth factors, cytokines, adenosine triphosphate (ATP), and nitric oxide (NO). Many of these mediators have actions on neurons that can contribute to migraine. Conversely, neurons release factors such as norepinephrine and calcitonin gene-related peptide (CGRP) that act on cells native to blood vessels. Both normal and pathological events occurring within and between vascular cells could thus mediate bi-directional communication between vessels and the nervous system, without the need for changes in vascular tone. This review will discuss the potential contribution of the vasculature, specifically endothelial cells, to current neuronal mechanisms hypothesized to play a role in migraine. Hypothalamic activity, cortical spreading depression (CSD), and dural afferent input from the cranial meninges will be reviewed with a focus on how these mechanisms can influence or be impacted by blood vessels. Together, the data discussed will provide a framework by which vessels can be viewed as important potential contributors to migraine pathophysiology, even in light of the current uncertainty over the role of vasodilation in this disorder. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Neurovascular contributions to migraine: moving beyond vasodilation

PubMed Central

Jacobs, Blaine; Dussor, Gregory

2016-01-01

Migraine is the third most common disease worldwide, the most common neurological disorder, and one of the most common pain conditions. Despite its prevalence, the basic physiology and underlying mechanisms contributing to the development of migraine is still poorly understood and development of new therapeutic targets is long overdue. Until recently, the major contributing pathophysiological event thought to initiate migraine was cerebral and meningeal arterial vasodilation. However, the role of vasodilation in migraine is unclear and recent findings challenge its necessity. While vasodilation itself may not contribute to migraine, it remains possible that vessels play a role in migraine pathophysiology in the absence of vasodilation. Blood vessels consist of a variety of cell types that both release and respond to numerous mediators including growth factors, cytokines, adenosine triphosphate (ATP), and nitric oxide (NO). Many of these mediators have actions on neurons that can contribute to migraine. Conversely, neurons release factors such as norepinephrine and calcitonin gene-related peptide (CGRP) that act on cells native to blood vessels. Both normal and pathological events occurring within and between vascular cells could thus mediate bi-directional communication between vessels and the nervous system, without the need for changes in vascular tone. This review will discuss the potential contribution of the vasculature, specifically endothelial cells, to current neuronal mechanisms hypothesized to play a role in migraine. Hypothalamic activity, cortical spreading depression (CSD), and dural afferent input from the cranial meninges will be reviewed with a focus on how these mechanisms can influence or be impacted by blood vessels. Together, the data discussed will provide a framework by which vessels can be viewed as important potential contributors to migraine pathophysiology, even in light of the current uncertainty over the role of vasodilation in this disorder. PMID:27312704

Seguridad del paciente en Radioterapia Intraoperatoria: Impacto de los elementos controlados por el Radiofisico

NASA Astrophysics Data System (ADS)

Tarjuelo, Juan Lopez

Introduccion: En la administracion de la radioterapia intervienen profesionales y equipos de tratamiento, por lo que existe el riesgo de error y se precisa que dicho equipamiento funcione conforme a lo esperado. A los radiofisicos les corresponde participar en las actividades de garantia o aseguramiento de la calidad, incluyendo el control de calidad de los equipos, y en la evaluacion de los riesgos asociados. La radioterapia intraoperatoria (RIO) es una tecnica radioterapica de intensificacion de dosis, altamente selectiva, dirigida a volumenes anatomicos restringidos durante el tratamiento quirurgico oncologico, basada en la administracion de una dosis absorbida alta por medio de un haz de electrones tras el examen visual directo del lecho tumoral. Como incorporar los ultimos avances en el refuerzo de la seguridad en radioterapia es una tarea ambiciosa y compleja, resulta mas concreta y de inmediata aplicacion su introduccion en la RIO. El objetivo es analizar los elementos que reducen los riesgos y aumentan la seguridad en la RIO y su dosimetria, y valorar la funcion del radiofisico en esta labor. Material y metodos: Se emplearon el planificador Radiance de GMV y el acelerador lineal de los tratamientos de RIO Elekta Precise, controlado con el verificador diario de haces Daily QA Check 1090 y medido con las camaras de ionizacion PPC 40, FC65-G y FC65-P de PTW-Freiburg, a su vez verificadas con fuentes radiactivas adecuadas de estroncio-90 modelos CDP y CDC de IBA Dosimetry. Se realizo un analisis de modos de fallo y efectos (failure mode and effect analysis, FMEA) con el fin de identificar los elementos que forman la RIO y aplicar las herramientas necesarias para la minimizacion de los riesgos y la mejora de la seguridad en la tecnica. Se estudiaron las verificaciones diarias de dicho acelerador Precise con el control estadistico de procesos (statistical process control, SPC) y se simularon intervenciones para devolverlo al estado llamado en control. El SPC

Air Traffic Management Technology Demonstration-1 Concept of Operations (ATD-1 ConOps), Version 3.0

NASA Technical Reports Server (NTRS)

Baxley, Brian T.; Johnson, William C.; Scardina, John; Shay, Richard F.

2016-01-01

This document describes the goals, benefits, technologies, and procedures of the Concept of Operations (ConOps) for the Air Traffic Management (ATM) Technology Demonstration #1 (ATD-1), and provides an update to the previous versions of the document [ref 1 and ref 2].

Understanding the pros and cons of organ donation decision-making: Decisional balance and expressing donation intentions among African Americans.

PubMed

Flemming, Shauna St Clair; Redmond, Nakeva; Williamson, Dana Hz; Thompson, Nancy J; Perryman, Jennie P; Patzer, Rachel E; Arriola, Kimberly Jacob

2018-04-01

Increasing public commitment to organ donation is critical to improving donor kidney availability for end-stage renal disease patients desiring transplant. This study surveyed ( N = 1339) African Americans, measuring perceived pros relative to cons of organ donation, to evaluate an existing Transtheoretical Model decisional balance scale and associations between decisional balance and expressing donation intentions. Findings supported the existing scale structure. More positive decisional balance ratios were associated with 1.76 times the odds of expressing intentions (95% confidence interval = 1.52-2.04). Pros were more strongly linked to donation intentions than cons. Greater understanding of organ donation decision-making is valuable for informing interventions that encourage donation.

Development of Point of Care Testing Device for Neurovascular Coupling From Simultaneous Recording of EEG and NIRS During Anodal Transcranial Direct Current Stimulation

PubMed Central

Jindal, Utkarsh; Sood, Mehak; Dutta, Anirban; Chowdhury, Shubhajit Roy

2015-01-01

This paper presents a point of care testing device for neurovascular coupling (NVC) from simultaneous recording of electroencephalogram (EEG) and near infrared spectroscopy (NIRS) during anodal transcranial direct current stimulation (tDCS). Here, anodal tDCS modulated cortical neural activity leading to hemodynamic response can be used to identify the impaired cerebral microvessels functionality. The impairments in the cerebral microvessels functionality may lead to impairments in the cerebrovascular reactivity (CVR), where severely reduced CVR predicts the chances of transient ischemic attack and ipsilateral stroke. The neural and hemodynamic responses to anodal tDCS were studied through joint imaging with EEG and NIRS, where NIRS provided optical measurement of changes in tissue oxy-(\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$HbO2)$ \\end{document} and deoxy-(\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$Hb$ \\end{document}) hemoglobin concentration and EEG captured alterations in the underlying neuronal current generators. Then, a cross-correlation method for the assessment of NVC underlying the site of anodal tDCS is presented. The feasibility studies on healthy subjects and stroke survivors showed detectable changes in the EEG and the NIRS responses to a 0.526 A/\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$\\mathrm{m}^{2}$ \\end{document} of anodal tDCS. The NIRS system

Cannabinoids and cancer: pros and cons of an antitumour strategy

PubMed Central

Bifulco, Maurizio; Laezza, Chiara; Pisanti, Simona; Gazzerro, Patrizia

2006-01-01

In the last two decades, research has dramatically increased the knowledge of cannabinoids biology and pharmacology. In mammals, compounds with properties similar to active components of Cannabis sativa, the so called ‘endocannabinoids', have been shown to modulate key cell-signalling pathways involved in cancer cell growth, invasion and metastasis. To date, cannabinoids have been licensed for clinical use as palliative treatment of chemotherapy, but increased evidences showed direct antiproliferative actions of cannabinoid agonists on several tumour cells in vitro and in animal models. In this article, we will review the principal molecular pathways modulated by cannabinoids on cancer and summarize pros and cons evidence on the possible future use of endocannabinoid-based drugs in cancer therapy. PMID:16501583

Salvianolic acid A inhibits calpain activation and eNOS uncoupling during focal cerebral ischemia in mice.

PubMed

Mahmood, Qaisar; Wang, Guang-Fa; Wu, Gang; Wang, Huan; Zhou, Chang-Xin; Yang, Hong-Yu; Liu, Zhi-Rong; Han, Feng; Zhao, Kui

2017-02-15

Salvianolic acid A (SAA) is obtained from Chinese herb Salviae Miltiorrhizae Bunge (Labiatae), has been reported to have the protective effects against cardiovascular and neurovascular diseases. The aim of present study was to investigate the relationship between the effectiveness of SAA against neurovascular injury and its effects on calpain activation and endothelial nitric oxide synthase (eNOS) uncoupling. SAA or vehicle was given to C57BL/6 male mice for seven days before the occlusion of middle cerebral artery (MCAO) for 60min. High-resolution positron emission tomography scanner (micro-PET) was used for small animal imaging to examine glucose metabolism. Rota-rod time and neurological deficit scores were calculated after 24h of reperfusion. The volume of infarction was determined by Nissl-staining. The calpain proteolytic activity and eNOS uncoupling were determined by western blot analysis. SAA administration increased glucose metabolism and ameliorated neuronal damage after brain ischemia, paralleled with decreased neurological deficit and volume of infarction. In addition, SAA pretreatment inhibited eNOS uncoupling and calpain proteolytic activity. Furthermore, SAA inhibited peroxynitrite (ONOO - ) generation and upregulates AKT, FKHR and ERK phosphorylation. These findings strongly suggest that SAA elicits a neurovascular protective role through the inhibition of eNOS uncoupling and ONOO - formation. Moreover, SAA attenuates spectrin and calcineurin breakdown and therefore protects the brain against ischemic/reperfusion injury. Copyright © 2016 Elsevier GmbH. All rights reserved.

Detrimental role of the EP1 prostanoid receptor in blood-brain barrier damage following experimental ischemic stroke

PubMed Central

Frankowski, Jan C.; DeMars, Kelly M.; Ahmad, Abdullah S.; Hawkins, Kimberly E.; Yang, Changjun; Leclerc, Jenna L.; Doré, Sylvain; Candelario-Jalil, Eduardo

2015-01-01

Cyclooxygenase-2 (COX-2) is activated in response to ischemia and significantly contributes to the neuroinflammatory process. Accumulation of COX-2-derived prostaglandin E2 (PGE2) parallels the substantial increase in stroke-mediated blood-brain barrier (BBB) breakdown. Disruption of the BBB is a serious consequence of ischemic stroke, and is mainly mediated by matrix metalloproteinases (MMPs). This study aimed to investigate the role of PGE2 EP1 receptor in neurovascular injury in stroke. We hypothesized that pharmacological blockade or genetic deletion of EP1 protects against BBB damage and hemorrhagic transformation by decreasing the levels and activity of MMP-3 and MMP-9. We found that post-ischemic treatment with the EP1 antagonist, SC-51089, or EP1 genetic deletion results in a significant reduction in BBB disruption and reduced hemorrhagic transformation in an experimental model of transient focal cerebral ischemia. These neurovascular protective effects of EP1 inactivation are associated with a significant reduction in MMP-9/-3, less peripheral neutrophil infiltration, and a preservation of tight junction proteins (ZO-1 and occludin) composing the BBB. Our study identifies the EP1 signaling pathway as an important link between neuroinflammation and MMP-mediated BBB breakdown in ischemic stroke. Targeting the EP1 receptor could represent a novel approach to diminish the devastating consequences of stroke-induced neurovascular damage. PMID:26648273

Neuroendovascular magnetic navigation: clinical experience in ten patients.

PubMed

Dabus, Guilherme; Gerstle, Ronald J; Cross, Dewitte T; Derdeyn, Colin P; Moran, Christopher J

2007-04-01

The magnetic navigation system consists of an externally generated magnetic field that is used to control and steer a magnetically tipped microguidewire. The goal of this study was to demonstrate that the use of the magnetic navigation system and its magnetic microguidewire is feasible and safe in all types of neuroendovascular procedures. A magnetic navigation system is an interventional workstation that combines a biplanar fluoroscopy system with a computer-controlled magnetic field generator to provide both visualization and control of a magnetically activated endovascular microguidewire. Ten consecutive patients underwent a variety of neuroendovascular procedures using the magnetic guidance system and magnetic microguidewire. All patients presented with a neurovascular disease that was suitable for endovascular treatment. Multiple different devices and embolic agents were used. Of the ten patients, three were male and seven female. Their mean age was 53.9 years. The predominant neurovascular condition was the presence of intracranial aneurysm (nine patients). One patient had a left mandibular arteriovenous malformation. All treatments were successfully performed on the magnetic navigation system suite. The magnetic navigation system and the magnetic microguidewire allowed safe and accurate endovascular navigation allowing placement of the microcatheters in the desired location. There were no neurological complications or death in our series. The use of the magnetic navigation system and the magnetic microguidewire in the endovascular treatment of patients with neurovascular diseases is feasible and safe.

Blood-Brain Barrier Integrity and Glial Support: Mechanisms that can be targeted for Novel Therapeutic Approaches in Stroke

PubMed Central

Ronaldson, Patrick T.; Davis, Thomas P.

2014-01-01

The blood-brain barrier (BBB) is a critical regulator of CNS homeostasis. Additionally, the BBB is the most significant obstacle to effective CNS drug delivery. It possesses specific charcteristics (i.e., tight junction protein complexes, influx and efflux transporters) that control permeation of circulating solutes including therapeutic agents. In order to form this “barrier,” brain microvascular endothelial cells require support of adjacent astrocytes and microglia. This intricate relationship also occurs between endothelial cells and other cell types and structures of the CNS (i.e., pericytes, neurons, extracellular matrix), which implies existence of a “neurovascular unit.” Ischemic stroke can disrupt the neurovascular unit at both the structural and functional level, which leads to an increase in leak across the BBB. Recent studies have identified several pathophysiological mechanisms (i.e., oxidative stress, activation of cytokine-mediated intracellular signaling systems) that mediate changes in the neurovascular unit during ischemic stroke. This review summarizes current knowledge in this area and emphasizes pathways (i.e., oxidative stress, cytokine-mediated intracellular signaling, glial-expressed receptors/targets) that can be manipulated pharmacologically for i) preservation of BBB and glial integrity during ischemic stroke and ii) control of drug permeation and/or transport across the BBB in an effort to identify novel targets for optimization of CNS delivery of therapeutics in the setting of ischemic stroke. PMID:22574987

Avoiding Pitfalls of Tibiotalocalcaneal Nail Malposition With Internal Rotation Axial Heel View.

PubMed

Callahan, Ryan; Juliano, Paul; Aydogan, Umur; Clayton, Justin

2018-04-01

Tibiotalocalcaneal (TTC) nails are often used for complex hind foot arthrodesis and deformity correction. The natural valgus alignment of the hindfoot creates a challenge to optimum placement of the guidewire and eventual nail with a straight or valgus-curved nail. Five fresh frozen cadavers were used for placement of a TTC guidewire with standard anterior-posterior (AP), lateral, and Harris axial heel views as a reference for proper placement. The limb was then rotated 15°, 30°, and 45° both internally and externally to evaluate the perceived amount of osseous purchase within the calcaneus. The TTC nail was then inserted and dissection was performed to demonstrate proximity of the nail to the sustentaculum tali and neurovascular structures. A 30° internal rotation Harris axial heel view demonstrated the most accurate representation of osseous purchase within the calcaneus with the guidewire and nail placement. When the guidewire was placed with standard imaging the nail was often ultimately placed in close proximity to the sustentaculum tali and neurovascular structures. Careful placement of the guidewire prior to reaming and nail placement should be undertaken to avoid neurovascular injury and to increase osseous purchase. For optimal guidewire placement, the authors suggest using appropriate anatomic landmarks and using a 30° internally rotated Harris axial heel view to verify correct placement. Level V: Expert opinion.

La mortalidad en adolescentes con cáncer: características clinicoepidemiológicas de muerte y aspectos éticos emergentes.

PubMed

Cicero-Oneto, Carlo Egysto; Mata-Valderrama, Guadalupe; Valdez-Martínez, Edith

Describir los aspectos epidemiológicos, clínicos y éticos de la mortalidad de los adolescentes con cáncer en -México. Se revisaron 63 expedientes clínicos de adolescentes (de 14 a 18 años de edad) con cáncer, fallecidos entre 2011 y 2014, para obtener información clínica y epidemiológica de su muerte. Los sitios de estudio fueron tres hospitales de concentración en la Ciudad de México. De los 40 adolescentes con criterios de fase terminal, 16 (40%) continuaron recibiendo tratamiento con fines curativos. De los 51 cuyo lugar de muerte era conocido, 45 (88%) murieron en hospital. De los 41 que murieron dentro de los 30 días de su última hospitalización, las muertes fueron principalmente debidas a complicaciones (51%), a progresión de la enfermedad (41%) o bien fueron muertes en tratamiento paliativo (7%, 3/41). La práctica oncológica descansa en lo que es conocido como modelo biomédico. Los resultados del estudio sugieren y apoyan la urgente necesidad de implementar verdaderos servicios de cuidados paliativos, pero más importante que eso, está el ímpetu de poner la ética de la práctica clínica en acción, y de ese modo reforzar la buena práctica de la medicina. Copyright: © 2018 SecretarÍa de Salud

Quick fix or long-term cure? Pros and cons of bariatric surgery

PubMed Central

Madura, James A.

2012-01-01

The past decade has seen an enormous increase in the number of bariatric, or weight loss, operations performed. This trend is likely to continue, mirroring the epidemic of obesity around the world and its rising prevalence among children. Bariatric surgery is considered by many to be the most effective treatment for obesity in terms of maintenance of long-term weight loss and improvement in obesity-related comorbid conditions. Although overly simplified, the primary mechanisms of the surgical interventions currently utilized to treat obesity are the creation of a restrictive or malabsorptive bowel anatomy. Operations based on these mechanisms include the laparoscopic adjustable gastric band and laparoscopic vertical sleeve gastrectomy (considered primarily restrictive operations), the laparoscopic biliopancreatic diversion with or without a duodenal switch (primarily malabsorptive operation), and the laparoscopic Roux-en-Y gastric bypass (considered a combination restrictive and selective malabsorptive procedure). Each operation has pros and cons. Important considerations, for the patient and surgeon alike, in the decision to proceed with bariatric surgery include the technical aspects of the operation, postoperative complications including long-term nutritional problems, magnitude of initial and sustained weight loss desired, and correction of obesity-related comorbidities. Herein, the pros and cons of the contemporary laparoscopic bariatric operations are reviewed and ongoing controversies relating to bariatric surgery are discussed: appropriate patient selection, appropriate operation selection for an individual patient, surgeon selection, and how to measure success after surgery. PMID:23091563

Pros and cons of transcatheter aortic valve implantation (TAVI).

PubMed

Terré, Juan A; George, Isaac; Smith, Craig R

2017-09-01

Transcatheter aortic valve implantation (TAVI) or replacement (TAVR) was recently approved by the FDA for intermediate risk patients with severe aortic stenosis (AS). This technique was already worldwide adopted for inoperable and high-risk patients. Improved device technology, imaging analysis and operator expertise has reduced the initial worrisome higher complications rate associated with TAVR, making it comparable to surgical aortic valve replacement (SAVR). However, many answers need to be addressed before adoption in lower risk patients. This paper highlights the pros and cons of TAVI based mostly on randomized clinical trials involving the two device platforms approved in the United States. We focused our analysis on metrics that will play a key role in expanding TAVR indication in healthier individuals. We review the significance and gave a perspective on paravalvular leak (PVL), valve performance, valve durability, leaflet thrombosis, stroke and pacemaker requirement.

Encefalitis por anticuerpos contra el receptor de NMDA: experiencia con seis pacientes pediátricos. Potencial eficacia del metotrexato

PubMed Central

Bravo-Oro, Antonio; Abud-Mendoza, Carlos; Quezada-Corona, Arturo; Dalmau, Josep; Campos-Guevara, Verónica

2016-01-01

Introducción La encefalitis por anticuerpos contra el receptor de N-metil-D-aspartato (NMDA) es una entidad cada vez más diagnosticada en edad pediátrica. A diferencia de los adultos, en muchos casos no se asocia a tumores y las manifestaciones iniciales en niños más frecuentes son crisis convulsivas y trastornos del movimiento, mientras que en los adultos predominan las alteraciones psiquiátricas. Casos clínicos Presentamos seis casos pediátricos confirmados con anticuerpos contra la subunidad NR1 del receptor de NMDA en suero y líquido cefalorraquídeo. Cinco de los casos comenzaron con crisis convulsivas como manifestación clínica inicial antes de desarrollar el cuadro clásico de esta entidad. En todos los casos se utilizaron esteroides como primera línea de tratamiento, con los que sólo se observó control de las manifestaciones en uno, por lo que el resto de los pacientes requirió inmunomoduladores de segunda línea. Todos los pacientes recibieron metotrexato como tratamiento inmunomodulador para evitar recaídas y la evolución fue a la mejoría en todos ellos. Conclusiones En nuestra serie de pacientes con encefalitis por anticuerpos contra el receptor de NMDA, ninguno se asoció a tumores. Todos los casos recibieron metotrexato por lo menos durante un año, no observamos eventos adversos clínicos ni por laboratorio, ni hubo secuelas neurológicas ni recaídas durante el tratamiento. Aunque es una serie pequeña y es deseable incrementar el número y tiempo de evolución, consideramos el metotrexato una excelente alternativa como tratamiento inmunomodulador para esta patología. PMID:24150952

Multiparametric optical coherence tomography imaging of the inner retinal hemodynamic response to visual stimulation

NASA Astrophysics Data System (ADS)

Radhakrishnan, Harsha; Srinivasan, Vivek J.

2013-08-01

The hemodynamic response to neuronal activation is a well-studied phenomenon in the brain, due to the prevalence of functional magnetic resonance imaging. The retina represents an optically accessible platform for studying lamina-specific neurovascular coupling in the central nervous system; however, due to methodological limitations, this has been challenging to date. We demonstrate techniques for the imaging of visual stimulus-evoked hyperemia in the rat inner retina using Doppler optical coherence tomography (OCT) and OCT angiography. Volumetric imaging with three-dimensional motion correction, en face flow calculation, and normalization of dynamic signal to static signal are techniques that reduce spurious changes caused by motion. We anticipate that OCT imaging of retinal functional hyperemia may yield viable biomarkers in diseases, such as diabetic retinopathy, where the neurovascular unit may be impaired.

Molecular parallels between neural and vascular development.

PubMed

Eichmann, Anne; Thomas, Jean-Léon

2013-01-01

The human central nervous system (CNS) features a network of ~400 miles of blood vessels that receives >20% of the body's cardiac output and uses most of its blood glucose. Many human diseases, including stroke, retinopathy, and cancer, are associated with the biology of CNS blood vessels. These vessels originate from extrinsic cell populations, including endothelial cells and pericytes that colonize the CNS and interact with glia and neurons to establish the blood-brain barrier and control cerebrovascular exchanges. Neurovascular interactions also play important roles in adult neurogenic niches, which harbor a unique population of neural stem cells that are intimately associated with blood vessels. We here review the cellular and molecular mechanisms required to establish the CNS vascular network, with a special focus on neurovascular interactions and the functions of vascular endothelial growth factors.

The anteromedial approach to the psoas tendon in patients with cerebral palsy

PubMed Central

Poonnoose, Pradeep M.; Palocaren, Thomas

2007-01-01

Purpose Release of the psoas tendon for flexion deformity of the hip in children with cerebral palsy has traditionally been performed at the pelvic brim, lateral to the neurovascular bundle, or at its insertion into the lesser trochanter. As the psoas tendon is lateral to the pectineus, the traditional exposure of the tendon through an approach medial to the pectineus is limited by the extent to which the pectineus can be retracted proximally. Technical note We describe the use of the anteromedial approach used for the developmentally dislocated hip to expose the psoas tendon between the pectineus and the neurovascular bundle. This provides a much better visualisation of the tendon as it crosses the superior pubic ramus to its insertion. The use of this approach has not been described in cerebral palsy. PMID:19308518

Anatomic structures at risk: curved hindfoot arthrodesis nail--a cadaveric approach.

PubMed

Knight, Timothy; Rosenfeld, Peter; Jones, Ioan Tudur; Clark, Callum; Savva, Nick

2014-01-01

Retrograde intramedullary nailing of the hindfoot and ankle is an established procedure for salvage of severe foot and ankle deformity, arthritis, tumor, and instability. In the present study, retrograde hindfoot (tibiotalocalcaneal) arthrodesis nailing was performed using a standardized technique on 7 cadaver specimens by trained senior surgeons. The specimens were then dissected to determine the distance of the subcalcaneal structures at risk from the insertion point of the nail. The findings showed that the distance of the lateral neurovascular bundle from the edge of the nail was 6.5 (range 3.5 to 8, 95% confidence interval 5.9 to 7.1) mm. No neurovascular bundle was compromised, and all were within a previously described "safe window." Copyright © 2014 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Hable con Ella (Talk to Her) through the lens of gender.

PubMed

Yanof, Judith A

2008-04-01

In the 2002 film Hable con Ella (Talk to Her), Spanish writer-director Pedro Almodóvar plays with the ambiguity of gender, transcending conventional assumptions about "masculinity" and "femininity." Each of the four main characters holds complex, varied, and, in some cases, gender-bending gender identifications. The theme of gender plasticity is a prominent motif in this film. However, underlying the narrative, there is also a perverse subtext that relies on rigidly binary gender stereotypes to define relationships between men and women. Both these views of gender which operate dialectically, create a complex tapestry through which Almodóvar explores his characters' problems in attaining intimacy.

Fairfax County and the Commonwealth of Virginia Public Safety and Transportation Operations Center : concept of cooperation (ConCoop)

DOT National Transportation Integrated Search

2005-01-01

The Public Safety and Transportation Operations Centers (PSTOCs) Concept of Cooperation (ConCoop) enables partner agencies to lay out and reach consensus on: : their intentions in co-locating; : joint functions and systems needed to mee...

To Bind or Not To Bind: Pros & Cons of Maintaining Paper Periodicals in the Library's Collection.

ERIC Educational Resources Information Center

Anderson, Iris W.

1999-01-01

Explores controversial questions related to libraries' decision-making on paper journals and electronic journals. Notes that the critical mass of scholarly publishing is still in print. Discusses benefits and drawbacks of electronic journals and paper journals. Presents comments on the pros and cons to binding paper periodicals gathered from an…

Pros and Cons of the Acceleration Scheme (NF-IDS)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bogacz, Alex; Bogacz, Slawomir

The overall goal of the acceleration systems: large acceptance acceleration to 25 GeV and beam shaping can be accomplished by various fixed field accelerators at different stages. They involve three superconducting linacs: a single pass linear Pre-accelerator followed by a pair of multi-pass Recirculating Linear Accelerators (RLA) and finally a nonâ scaling FFAG ring. The present baseline acceleration scenario has been optimized to take maximum advantage of appropriate acceleration scheme at a given stage. Pros and cons of various stages are discussed here in detail. The solenoid based Pre-accelerator offers very large acceptance and facilitates correction of energy gain acrossmore » the bunch and significant longitudinal compression trough induced synchrotron motion. However, far off-crest acceleration reduces the effective acceleration gradient and adds complexity through the requirement of individual RF phase control for each cavity. Close proximity of strong solenoids and superc« less

Pros and cons of transcatheter aortic valve implantation (TAVI)

PubMed Central

Terré, Juan A.; George, Isaac

2017-01-01

Transcatheter aortic valve implantation (TAVI) or replacement (TAVR) was recently approved by the FDA for intermediate risk patients with severe aortic stenosis (AS). This technique was already worldwide adopted for inoperable and high-risk patients. Improved device technology, imaging analysis and operator expertise has reduced the initial worrisome higher complications rate associated with TAVR, making it comparable to surgical aortic valve replacement (SAVR). However, many answers need to be addressed before adoption in lower risk patients. This paper highlights the pros and cons of TAVI based mostly on randomized clinical trials involving the two device platforms approved in the United States. We focused our analysis on metrics that will play a key role in expanding TAVR indication in healthier individuals. We review the significance and gave a perspective on paravalvular leak (PVL), valve performance, valve durability, leaflet thrombosis, stroke and pacemaker requirement. PMID:29062739

Reacciones de intercambio de carga

NASA Astrophysics Data System (ADS)

Errea, L. F.

Se discute la validez de diversas metodologías y su aplicación al estudio de procesos de intercambio de carga electrónico entre iones y blancos atómicos y moleculares. Para energías de impacto entre 0.05 y 5 eV / amu se emplea el método cuántico de la Coordenada de Reacción Común (CRC). A mayores energías, se utiliza el método semiclásico iconal con un desarrollo de la función de onda dinámica en estados moleculares adiabáticos, modificados con un factor de traslación común (FTC). Estos estados pueden obtenerse con cálculos ab initio o empleando potenciales modelo. Cuando la ionización compite con la transferencia de carga, la inclusión de pseudoestados en estos desarrollos permite calcular simultáneamente las secciones eficaces de ambos procesos. Otra técnica utilizada es el método estadístico CTMC. En el tratamiento de colisiones ión-molécula (diatómica) contrastamos la aplicabilidad de distintos métodos, desde la llamada aproximación Franck-Condon hasta un desarrollo en estados vibrónicos, pasando por la aproximación súbita vibro-rotacional, obteniéndose secciones eficaces de captura electrónica total y a estados individuales, así como secciones de excitación vibracional a estados ligados y del continuo (disociación). En todos los casos es necesario calcular superficies de energía y los correspondientes acoplamientos dinámicos entre los estados. La aplicación de estos métodos permite determinar el grado de contaminación de los haces por estados metaestables en un experimento dado, el cambio en los resultados con diferentes isótopos, la importancia de procesos de doble captura, seguida de explosión culombiana, todo ello con precisión comparable a la de medidas experimentales, para sistemas de interés en distintos tipos de plasmas.

Variability and reliability of the vastus lateralis muscle anatomy.

PubMed

D'Arpa, Salvatore; Toia, Francesca; Brenner, Erich; Melloni, Carlo; Moschella, Francesco; Cordova, Adriana

2016-08-01

The aims of this study are to investigate the variability of the morphological and neurovascular anatomy of the vastus lateralis (VL) muscle and to describe the relationships among its intramuscular partitions and with the other muscles of the quadriceps femoris. Clinical implications in its reliability as a flap donor are also discussed. In 2012, the extra- and intramuscular neurovascular anatomy of the VL was investigated in 10 cadaveric lower limbs. In three specimens, the segmental arterial pedicles were injected with latex of different colors to point out their anastomotic connections. The morphological anatomy was investigated with regard to the mutual relationship of the three muscular partitions and the relation of the VL with the other muscles of the quadriceps femoris. The VL has a segmental morphological anatomy. However, the fibers of its three partitions interconnect individually and with the other bellies of the quadriceps femoris, particularly, in several variable portions with the vastus intermedius and mainly in the posterior part of the VL. The lateral circumflex femoral artery and its branches have variable origin, but demonstrate constant segmental distribution. Intramuscular dissection and colored latex injections show a rich anastomotic vascular network among the three partitions. Moderate variability exists in both the myological and the neurovascular anatomy of the VL. Despite this variability, the anatomy of the VL always has a constant segmental pattern, which makes the VL a reliable flap donor. Detailed knowledge of the VL anatomy could have useful applications in a broad clinical field.

Vascular cognitive impairment, dementia, aging and energy demand. A vicious cycle.

PubMed

Popa-Wagner, A; Buga, Ana-Maria; Popescu, B; Muresanu, D

2015-08-01

To a great extent, cognitive health depends on cerebrovascular health and a deeper understanding of the subtle interactions between cerebrovascular function and cognition is needed to protect humans from one of the most devastating affliction, dementia. However, the underlying biological mechanisms are still not completely clear. Many studies demonstrated that the neurovascular unit is compromised in cerebrovascular diseases and also in other types of dementia. The hemodynamic neurovascular coupling ensures a strong increase of the cerebral blood flow (CBF) and an acute increase in neuronal glucose uptake upon increased neural activity. Dysfunction of cerebral autoregulation with increasing age along with age-related structural and functional alterations in cerebral blood vessels including accumulation of amyloid-beta (Aβ) in the media of cortical arterioles, neurovascular uncoupling due to astrocyte endfeet retraction, impairs the CBF and increases the neuronal degeneration and susceptibility to hypoxia and ischemia. A decreased cerebral glucose metabolism is an early event in Alzheimer's disease (AD) pathology and may precede the neuropathological Aβ deposition associated with AD. Aβ accumulation in turn leads to further decreases in the CBF closing the vicious cycle. Alzheimer, aging and diabetes are also influenced by insulin/insulin-like growth factor-1 signaling, and accumulated evidence indicates sporadic AD is associated with disturbed brain insulin metabolism. Understanding how vascular and metabolic factors interfere with progressive loss of functional neuronal networks becomes essential to develop efficient drugs to prevent cognitive decline in elderly.

Tongue base reduction with hyoepiglottoplasty: a treatment for severe obstructive sleep apnea.

PubMed

Chabolle, F; Wagner, I; Blumen, M B; Séquert, C; Fleury, B; De Dieuleveult, T

1999-08-01

To describe a surgical procedure for the treatment of severe obstructive sleep apnea syndrome (OSAS), the procedure's indications, and its results. A retrospective study of 10 male patients with OSAS treated by tongue base reduction with hyoepiglottoplasty (TBRHE) at the Foch Hospital (Suresnes, France) between 1994 and 1997. Patients had a mean body mass index (BMI) of 32 kg/m2, a mean respiratory disturbance index (RDI) of 70 events/h, and a mean minimal oxygen saturation of 78%. They had refused positive airway pressure therapy or wished to discontinue it. Subtotal tongue base reduction preceded by lingual neurovascular bundle identification and derouting, epiglottal verticalization, mouth floor horizontalization, and hyoid bone repositioning was performed, associated in some cases to uvulopalatopharyngoplasty (UPPP). Indications were based on a site-related obstruction, on the absence of craniofacial deficiencies, and on the presence of hyolingual abnormalities determined by cephalometry and magnetic resonance imaging. TBRHE associated to UPPP in most cases had an 80% success rate, based on a postoperative RDI below 20 events/h and a reduction of the preoperative RDI of more than 50%. Snoring and excessive daytime sleepiness decreased or disappeared, respectively, in 100% and 90% of the cases. No neurovascular complications occurred. TBRHE is a safe procedure for the neurovascular bundle. Associated to a pharyngotomy, it is an effective treatment for severe OSAS attributable to tongue base obstruction. These results require confirmation in a larger series of patients.

Pros and cons of healthcare information technology implementation: the pros win.

PubMed

Maffei, Roxana

2006-01-01

Countless studies and investigations have been performed siding either for or against the implementation of technology in the healthcare setting. This article presents both sides of this debate, with an obvious conclusion that the pros of this debate win. The practice of information technology in the medical domain lags behind its knowledge and discovery by at least 7 years. The key to closing this gap is to show, through various studies, how information technology systems provide decision support to users at the point in time when decisions are needed. What the reader will obtain from this article is that the pros for information technology implementation in healthcare settings weigh much more and have a greater effect than the cons.

The ConNECT Framework: a model for advancing behavioral medicine science and practice to foster health equity

PubMed Central

Alcaraz, Kassandra I.; Sly, Jamilia; Ashing, Kimlin; Fleisher, Linda; Gil-Rivas, Virginia; Ford, Sabrina; Yi, Jean C.; Lu, Qian; Meade, Cathy D.; Menon, Usha; Gwede, Clement K.

2017-01-01

Health disparities persist despite ongoing efforts. Given the United States’ rapidly changing demography and socio-cultural diversity, a paradigm shift in behavioral medicine is needed to advance research and interventions focused on health equity. This paper introduces the Con-NECT Framework as a model to link the sciences of behavioral medicine and health equity with the goal of achieving equitable health and outcomes in the twenty-first century. We first evaluate the state of health equity efforts in behavioral medicine science and identify key opportunities to advance the field. We then discuss and present actionable recommendations related to ConNECT’s five broad and synergistic principles: (1) Integrating Context; (2) Fostering a Norm of Inclusion; (3) Ensuring Equitable Diffusion of Innovations; (4) Harnessing Communication Technology; and (5) Prioritizing Specialized Training. The framework holds significant promise for furthering health equity and ushering in a new and refreshing era of behavioral medicine science and practice. PMID:27509892

The ConNECT Framework: a model for advancing behavioral medicine science and practice to foster health equity.

PubMed

Alcaraz, Kassandra I; Sly, Jamilia; Ashing, Kimlin; Fleisher, Linda; Gil-Rivas, Virginia; Ford, Sabrina; Yi, Jean C; Lu, Qian; Meade, Cathy D; Menon, Usha; Gwede, Clement K

2017-02-01

Health disparities persist despite ongoing efforts. Given the United States' rapidly changing demography and socio-cultural diversity, a paradigm shift in behavioral medicine is needed to advance research and interventions focused on health equity. This paper introduces the ConNECT Framework as a model to link the sciences of behavioral medicine and health equity with the goal of achieving equitable health and outcomes in the twenty-first century. We first evaluate the state of health equity efforts in behavioral medicine science and identify key opportunities to advance the field. We then discuss and present actionable recommendations related to ConNECT's five broad and synergistic principles: (1) Integrating Context; (2) Fostering a Norm of Inclusion; (3) Ensuring Equitable Diffusion of Innovations; (4) Harnessing Communication Technology; and (5) Prioritizing Specialized Training. The framework holds significant promise for furthering health equity and ushering in a new and refreshing era of behavioral medicine science and practice.

Brain mesenchymal stem cells: physiology and pathological implications.

PubMed

Pombero, Ana; Garcia-Lopez, Raquel; Martinez, Salvador

2016-06-01

Mesenchymal stem cells (MSCs) are defined as progenitor cells that give rise to a number of unique, differentiated mesenchymal cell types. This concept has progressively evolved towards an all-encompassing concept including multipotent perivascular cells of almost any tissue. In central nervous system, pericytes are involved in blood-brain barrier, and angiogenesis and vascular tone regulation. They form the neurovascular unit (NVU) together with endothelial cells, astrocytes and neurons. This functional structure provides an optimal microenvironment for neural proliferation in the adult brain. Neurovascular niche include both diffusible signals and direct contact with endothelial and pericytes, which are a source of diffusible neurotrophic signals that affect neural precursors. Therefore, MSCs/pericyte properties such as differentiation capability, as well as immunoregulatory and paracrine effects make them a potential resource in regenerative medicine. © 2016 Japanese Society of Developmental Biologists.

Corrigendum.

PubMed

2018-01-01

Arenillas JF, Cortijo E, García-Bermejo P, et al. Relative cerebral blood volume is associated with collateral status and infarct growth in stroke patients in SWIFT PRIME. J Cereb Blood Flow Metab. Epub ahead of print 1 January 2017. DOI: 10.1177/0271678X17740293 . This article was published online with the sixth author, David Liebeskind (Neurovascular Imaging Research Core, Department of Neurology, UCLA, USA), omitted. The full list and order of authors on the article is as follows: Juan F Arenillas, Elisa Cortijo, Pablo García-Bermejo, Elad I Levy, Reza Jahan, David Liebeskind, Mayank Goyal, Jeffrey L Saver and Gregory W Albers Juan F Arenillas's affiliation should have read Neurovascular Research i3 Laboratory, Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Valladolid, Valladolid, Spain.

Molecular Parallels between Neural and Vascular Development

PubMed Central

Eichmann, Anne; Thomas, Jean-Léon

2013-01-01

The human central nervous system (CNS) features a network of ∼400 miles of blood vessels that receives >20% of the body’s cardiac output and uses most of its blood glucose. Many human diseases, including stroke, retinopathy, and cancer, are associated with the biology of CNS blood vessels. These vessels originate from extrinsic cell populations, including endothelial cells and pericytes that colonize the CNS and interact with glia and neurons to establish the blood–brain barrier and control cerebrovascular exchanges. Neurovascular interactions also play important roles in adult neurogenic niches, which harbor a unique population of neural stem cells that are intimately associated with blood vessels. We here review the cellular and molecular mechanisms required to establish the CNS vascular network, with a special focus on neurovascular interactions and the functions of vascular endothelial growth factors. PMID:23024177

The Protective Effect of Intrasplenic Transplantation of Ad-IL-18BP/IL-4 Gene-Modified Fetal Hepatocytes on ConA-Induced Hepatitis in Mice

PubMed Central

Xu, Chenhuai; Hong, Bo; Xu, Wanhong; Shen, Ling; Jin, Changzhong; Wu, Zhigang; Tong, Xiangmin; Yao, Hangping

2013-01-01

Background Concanavalin A (ConA)-induced hepatitis is an experimental murine model mirroring the pathology of human autoimmune hepatitis. Aim To investigate the effects of intrasplenically transplanted fetal hepatocytes (BNL.CL2) transfected with recombinant adenovirus vector expressing the IL-18 binding protein (IL-18BP) and IL-4 fusion protein on ConA-induced hepatitis in mice. Methods Ad-IL-18BP/IL-4 was used to infect BNL.CL2 cells. IL-4 and IL-18BP fusion protein expression were detected by ELISA and Western blotting. BNL.CL2 cells infected with Ad-IL-18BP/IL-4 were intrasplenically transplanted into mice. After 10 days, mice were injected with ConA (15 mg/kg), and sacrificed 18 hours later. Liver injury was assessed by serum transaminase and liver histology. TNF-α, IL-18, IL-4, IL-10, IL-12p70 and monocyte-chemoattracting protein (MCP)-1 levels in serum and liver homogenates were detected by ELISA. Signaling molecules in liver homogenates were analyzed by Western blotting. Results Ad-IL-18BP/IL-4 effectively expressed the IL-18BP/IL-4 fusion protein for more than 14 days in BNL.CL12 cells. Treatment of mice with Ad-IL-18BP/IL-4-BNL.CL2 before ConA injection significantly reduced the elevated plasma levels of transaminases compared with ConA control groups. TNF-α, IL-18, IL-12p70 and MCP-1 levels in serum and liver homogenates from mice transplanted with Ad-IL-18BP/IL-4-BNL.CL2 were lower and IL-4 and IL-10 levels were higher than control groups. Phosphorylation levels of NF-κB p65, AKT, p38 and JNK1/2 in liver homogenates were markedly suppressed by Ad-IL-18BP/IL-4. Conclusions Ad-IL-18BP/IL-4 was effectively transfected into mouse BNL.CL2 cells. Intrasplenic transplantation of Ad-IL-18BP/IL-4-BNL.CL12 cells alleviated the severity of inflammation in ConA-induced experimental hepatitis and provides a useful basis for the targeted gene therapy of liver disease. PMID:23516562

The protective effect of intrasplenic transplantation of Ad-IL-18BP/IL-4 gene-modified fetal hepatocytes on ConA-induced hepatitis in mice.

PubMed

Shao, Xueting; Qian, Yun; Xu, Chenhuai; Hong, Bo; Xu, Wanhong; Shen, Ling; Jin, Changzhong; Wu, Zhigang; Tong, Xiangmin; Yao, Hangping

2013-01-01

Concanavalin A (ConA)-induced hepatitis is an experimental murine model mirroring the pathology of human autoimmune hepatitis. To investigate the effects of intrasplenically transplanted fetal hepatocytes (BNL.CL2) transfected with recombinant adenovirus vector expressing the IL-18 binding protein (IL-18BP) and IL-4 fusion protein on ConA-induced hepatitis in mice. Ad-IL-18BP/IL-4 was used to infect BNL.CL2 cells. IL-4 and IL-18BP fusion protein expression were detected by ELISA and Western blotting. BNL.CL2 cells infected with Ad-IL-18BP/IL-4 were intrasplenically transplanted into mice. After 10 days, mice were injected with ConA (15 mg/kg), and sacrificed 18 hours later. Liver injury was assessed by serum transaminase and liver histology. TNF-α, IL-18, IL-4, IL-10, IL-12p70 and monocyte-chemoattracting protein (MCP)-1 levels in serum and liver homogenates were detected by ELISA. Signaling molecules in liver homogenates were analyzed by Western blotting. Ad-IL-18BP/IL-4 effectively expressed the IL-18BP/IL-4 fusion protein for more than 14 days in BNL.CL12 cells. Treatment of mice with Ad-IL-18BP/IL-4-BNL.CL2 before ConA injection significantly reduced the elevated plasma levels of transaminases compared with ConA control groups. TNF-α, IL-18, IL-12p70 and MCP-1 levels in serum and liver homogenates from mice transplanted with Ad-IL-18BP/IL-4-BNL.CL2 were lower and IL-4 and IL-10 levels were higher than control groups. Phosphorylation levels of NF-κB p65, AKT, p38 and JNK1/2 in liver homogenates were markedly suppressed by Ad-IL-18BP/IL-4. Ad-IL-18BP/IL-4 was effectively transfected into mouse BNL.CL2 cells. Intrasplenic transplantation of Ad-IL-18BP/IL-4-BNL.CL12 cells alleviated the severity of inflammation in ConA-induced experimental hepatitis and provides a useful basis for the targeted gene therapy of liver disease.

Nanoparticulas basadas en complejos de Fe(II) con transicion de espin: sintesis, caracterizacion y aplicaciones en electronica molecular

NASA Astrophysics Data System (ADS)

Monrabal Capilla, Maria

Esta tesis doctoral esta organizada en 5 capitulos y esta destinada al estudio de sistemas de Fe (II) que presentan el fenomeno de la transicion de espin a escala nanometrica. El capitulo 1 contiene una introduccion general sobre materiales moleculares multifuncionales, destacando aquellos ejemplos mas importantes. Por otro lado, se explicara el fenomeno de la transicion de espin, tratando aspectos conceptuales, los antecedentes mas importantes y la situacion actual. En el capitulo 2 se describen los diferentes procesos existentes para la obtencion de diferentes tipos de nanoparticulas. Ademas, se presenta la sintesis y caracterizacion de nanoparticulas del polimero de coordinacion unidimensional [Fe(Htrz)2(trz)]BF4, obtenidas mediante el metodo de micelas inversas. Estas nanoparticulas, con una estrecha distribucion de tamanos centrada alrededor de los 11 nm, presentan una transicion de espin muy abrupta, con un ancho ciclo de histeresis termica de unos 40K. En el capitulo 3 se describe el proceso de modificacion del tamano de las nanoparticulas descritas en el capitulo anterior, llevado a cabo variando la proporcion de surfactante/H2O en el medio. Ademas, con el objetivo de modificar las propiedades magneticas de las nanoparticulas obtenidas en el capitulo 2, se lleva a cabo la sintesis de nanoparticulas de polimeros de la misma familia del [Fe(Htrz)2(trz)]BF4. En concreto se sintetizaron 3 nuevos tipos de nanoparticulas basadas en el polimero [Fe(Htrz)1-x(NH2trz)x](ClO4)2, siendo x = 0.05, 0.15 y 0.3, en cada caso. Estas nanoparticulas siguen presentando una estrecha distribucion de tamanos y una transicion de espin muy abrupta y con un ancho ciclo de histeresis. Ademas, se observa que este ciclo se desplaza a temperaturas mas proximas a la temperatura ambiente a medida que se aumenta el porcentaje de 4-amino-1, 2, 4- triazol en la muestra. Pero al mismo tiempo se produce una disminucion de la anchura de este ciclo. Por ultimo, en este capitulo se presenta la

Establishing confidence in the output of qualitative research synthesis: the ConQual approach.

PubMed

Munn, Zachary; Porritt, Kylie; Lockwood, Craig; Aromataris, Edoardo; Pearson, Alan

2014-09-20

The importance of findings derived from syntheses of qualitative research has been increasingly acknowledged. Findings that arise from qualitative syntheses inform questions of practice and policy in their own right and are commonly used to complement findings from quantitative research syntheses. The GRADE approach has been widely adopted by international organisations to rate the quality and confidence of the findings of quantitative systematic reviews. To date, there has been no widely accepted corresponding approach to assist health care professionals and policy makers in establishing confidence in the synthesised findings of qualitative systematic reviews. A methodological group was formed develop a process to assess the confidence in synthesised qualitative research findings and develop a Summary of Findings tables for meta-aggregative qualitative systematic reviews. Dependability and credibility are two elements considered by the methodological group to influence the confidence of qualitative synthesised findings. A set of critical appraisal questions are proposed to establish dependability, whilst credibility can be ranked according to the goodness of fit between the author's interpretation and the original data. By following the processes outlined in this article, an overall ranking can be assigned to rate the confidence of synthesised qualitative findings, a system we have labelled ConQual. The development and use of the ConQual approach will assist users of qualitative systematic reviews to establish confidence in the evidence produced in these types of reviews and can serve as a practical tool to assist in decision making.

Soy-Based Therapeutic Baby Formulas: Testable Hypotheses Regarding the Pros and Cons.

PubMed

Westmark, Cara J

2016-01-01

Soy-based infant formulas have been consumed in the United States since 1909, and currently constitute a significant portion of the infant formula market. There are efforts underway to generate genetically modified soybeans that produce therapeutic agents of interest with the intent to deliver those agents in a soy-based infant formula platform. The threefold purpose of this review article is to first discuss the pros and cons of soy-based infant formulas, then present testable hypotheses to discern the suitability of a soy platform for drug delivery in babies, and finally start a discussion to inform public policy on this important area of infant nutrition.

Soy-Based Therapeutic Baby Formulas: Testable Hypotheses Regarding the Pros and Cons

PubMed Central

Westmark, Cara J.

2017-01-01

Soy-based infant formulas have been consumed in the United States since 1909, and currently constitute a significant portion of the infant formula market. There are efforts underway to generate genetically modified soybeans that produce therapeutic agents of interest with the intent to deliver those agents in a soy-based infant formula platform. The threefold purpose of this review article is to first discuss the pros and cons of soy-based infant formulas, then present testable hypotheses to discern the suitability of a soy platform for drug delivery in babies, and finally start a discussion to inform public policy on this important area of infant nutrition. PMID:28149839

CHILES Con Pol: Probing galaxy evolution, the dark Universe, and cosmic magnetism with a deep 1000 hour Jansky VLA survey

NASA Astrophysics Data System (ADS)

Hales, Christopher A.; Chiles Con Pol Collaboration

2014-04-01

We recently started a 1000 hour campaign to observe 0.2 square degrees of the COSMOS field in full polarization continuum at 1.4 GHz with the Jansky VLA, as part of a joint program with the spectral line COSMOS HI Large Extragalactic Survey (CHILES). When complete, we expect our CHILES Continuum Polarization (CHILES Con Pol) survey to reach an unprecedented SKA-era sensitivity of 0.7 uJy per 4 arcsecond FWHM beam. Here we present the key goals of CHILES Con Pol, which are to (i) produce a source catalog of legacy value to the astronomical community, (ii) measure differential source counts in total intensity, linear polarization, and circular polarization in order to constrain the redshift and luminosity distributions of source populations, (iii) perform a novel weak lensing study using radio polarization as an indicator of intrinsic alignment to better study dark energy and dark matter, and (iv) probe the unknown origin of cosmic magnetism by measuring the strength and structure of intergalactic magnetic fields in the filaments of large scale structure. The CHILES Con Pol source catalog will be a useful resource for upcoming wide-field surveys by acting as a training set for machine learning algorithms, which can then be used to identify and classify radio sources in regions lacking deep multiwavelength coverage.

Smart guidewires for smooth navigation in neurovascular intervention

NASA Astrophysics Data System (ADS)

Chen, Yanfei; Barry, Matthew M.; Shayan, Mahdis; Jankowitz, Brian T.; Duan, Xinjie; Robertson, Anne M.; Chyu, Minking K.; Chun, Youngjae

2015-04-01

A smart guidewire using nitinol materials was designed, manufactured and evaluated the device functionality, such as bending performance, trackability, thermal effects, and thrombogenic response. Two types of nitinol material were partially used to enhance the guidewire trackability. A proposed smart guidewire system uses either one- or two-way shape-memory alloy nitinol (1W-SMA, 2W-SMA) wires (0.015, 381µm nitinol wire). Bending stiffness was measured using in vitro test system, which contains the NI USB-9162 data logger and LabView Signal Express 2010. Temperature distribution and displacement were evaluated via recording a 60Hz movie using a SC325 camera. Hemocompatibility was evaluated by scanning electron microscopy after one heating cycle of nitinol under the Na-citrate porcine whole blood circulation. A smart guidewire showed 30 degrees bending after applying or disconnecting electrical current. While the temperature of the nitinol wires increased more than 70 °C, the surrounding temperature with the commercially available catheter coverings showed below human body temperature showing 30 ̴ 33 °C. There was no significant platelet attachment or blood coagulation when the guidewire operates. Novel smart guidewires have been developed using shape memory alloy nitinol, which may represent a novel alternative to typical commercially available guidewires for interventional procedures.

Modulation of Frontoparietal Neurovascular Dynamics in Working Memory

PubMed Central

Ardestani, Allen; Shen, Wei; Darvas, Felix; Toga, Arthur W.; Fuster, Joaquin M.

2016-01-01

Our perception of the world is represented in widespread, overlapping, and interactive neuronal networks of the cerebral cortex. A majority of physiological studies on the subject have focused on oscillatory synchrony as the binding mechanism for representation and transmission of neural information. Little is known, however, about the stability of that synchrony during prolonged cognitive operations that span more than just a few seconds. The present research, in primates, investigated the dynamic patterns of oscillatory synchrony by two complementary recording methods, surface field potentials (SFPs) and near-infrared spectroscopy (NIRS). The signals were first recorded during the resting state to examine intrinsic functional connectivity. The temporal modulation of coactivation was then examined on both signals during performance of working memory ( WM) tasks with long delays (memory retention epochs). In both signals, the peristimulus period exhibited characteristic features in frontal and parietal regions. Examination of SFP signals over delays lasting tens of seconds, however, revealed alternations of synchronization and desynchronization. These alternations occurred within the same frequency bands observed in the peristimulus epoch, without a specific correspondence between any definite cognitive process (e.g., WM) and synchrony within a given frequency band. What emerged instead was a correlation between the degree of SFP signal fragmentation (in time, frequency, and brain space) and the complexity and efficiency of the task being performed. In other words, the incidence and extent of SFP transitions between synchronization and desynchronization—rather than the absolute degree of synchrony—augmented in correct task performance compared with incorrect performance or in a control task without WM demand. An opposite relationship was found in NIRS: increasing task complexity induced more uniform, rather than fragmented, NIRS coactivations. These findings indicate that the particular features of neural oscillations cannot be linearly mapped to cognitive functions. Rather, information and the cognitive operations performed on it are primarily reflected in their modulations over time. The increased complexity and fragmentation of electrical frequencies in WM may reflect the activation of hierarchically diverse cognits (cognitive networks) in that condition. Conversely, the homogeneity in coherence of NIRS responses may reflect the cumulative vascular reactions that accompany that neuroelectrical proliferation of frequencies and the longer time constant of the NIRS signal. These findings are directly relevant to the mechanisms mediating cognitive processes and to physiologically based interpretations of functional brain imaging. PMID:26679214

In Vitro Cerebrovascular Modeling in the 21st Century: Current and Prospective Technologies

PubMed Central

Palmiotti, Christopher A.; Prasad, Shikha; Naik, Pooja; Abul, Kaisar MD; Sajja, Ravi K.; Achyuta, Anilkumar H.; Cucullo, Luca

2014-01-01

The blood-brain barrier (BBB) maintains the brain homeostasis and dynamically responds to events associated with systemic and/or rheological impairments (e.g., inflammation, ischemia) including the exposure to harmful xenobiotics. Thus, understanding the BBB physiology is crucial for the resolution of major central nervous system CNS) disorders challenging both health care providers and the pharmaceutical industry. These challenges include drug delivery to the brain, neurological disorders, toxicological studies, and biodefense. Studies aimed at advancing our understanding of CNS diseases and promoting the development of more effective therapeutics are primarily performed in laboratory animals. However, there are major hindering factors inherent to in vivo studies such as cost, limited throughput and translational significance to humans. These factors promoted the development of alternative in vitro strategies for studying the physiology and pathophysiology of the BBB in relation to brain disorders as well as screening tools to aid in the development of novel CNS drugs. Herein, we provide a detailed review including pros and cons of current and prospective technologies for modelling the BBB in vitro including ex situ, cell based and computational (in silico) models. A special section is dedicated to microfluidic systems including micro-BBB, BBB-on-a-chip, Neurovascular Unit-on-a-Chip and Synthetic Microvasculature Blood-Brain Barrier. PMID:25098812

In vitro cerebrovascular modeling in the 21st century: current and prospective technologies.

PubMed

Palmiotti, Christopher A; Prasad, Shikha; Naik, Pooja; Abul, Kaisar M D; Sajja, Ravi K; Achyuta, Anilkumar H; Cucullo, Luca

2014-12-01

The blood-brain barrier (BBB) maintains the brain homeostasis and dynamically responds to events associated with systemic and/or rheological impairments (e.g., inflammation, ischemia) including the exposure to harmful xenobiotics. Thus, understanding the BBB physiology is crucial for the resolution of major central nervous system CNS) disorders challenging both health care providers and the pharmaceutical industry. These challenges include drug delivery to the brain, neurological disorders, toxicological studies, and biodefense. Studies aimed at advancing our understanding of CNS diseases and promoting the development of more effective therapeutics are primarily performed in laboratory animals. However, there are major hindering factors inherent to in vivo studies such as cost, limited throughput and translational significance to humans. These factors promoted the development of alternative in vitro strategies for studying the physiology and pathophysiology of the BBB in relation to brain disorders as well as screening tools to aid in the development of novel CNS drugs. Herein, we provide a detailed review including pros and cons of current and prospective technologies for modelling the BBB in vitro including ex situ, cell based and computational (in silico) models. A special section is dedicated to microfluidic systems including micro-BBB, BBB-on-a-chip, Neurovascular Unit-on-a-Chip and Synthetic Microvasculature Blood-brain Barrier.

Ischemia-induced endothelial cell swelling and mitochondrial dysfunction are attenuated by dietary polyphenols in vitro

USDA-ARS?s Scientific Manuscript database

Polyphenols possess anti-oxidant and anti-inflammatory properties. Oxidative stress (OS) and inflammation have been implicated in the pathogenesis of cytotoxic brain edema in cerebral ischemia. In addition, OS and pro-inflammatory cytokines also damage the endothelial cells and the neurovascular uni...

Frontiers in Head and Neck Trauma: Clinical and Biomechanical.

DTIC Science & Technology

1998-06-19

Minerva fixation. As previously noted however, lateral mass plates have the risk for neurovascular injury (nerve root, vertebral artery), foraminal ...cord ischemia in CSM to include compromise of the anterior spinal veins, radicular arteries at the foraminal region, and vertebral artery narrowing as

Flight Deck Surface Trajectory-based Operations (STBO): Results of Piloted Simulations and Implications for Concepts of Operation (ConOps)

NASA Technical Reports Server (NTRS)

Foyle, David C.; Hooey, Becky L.; Bakowski, Deborah L.

2013-01-01

The results offour piloted medium-fidelity simulations investigating flight deck surface trajectory-based operations (STBO) will be reviewed. In these flight deck STBO simulations, commercial transport pilots were given taxi clearances with time and/or speed components and required to taxi to the departing runway or an intermediate traffic intersection. Under a variety of concept of operations (ConOps) and flight deck information conditions, pilots' ability to taxi in compliance with the required time of arrival (RTA) at the designated airport location was measured. ConOps and flight deck information conditions explored included: Availability of taxi clearance speed and elapsed time information; Intermediate RTAs at intermediate time constraint points (e.g., intersection traffic flow points); STBO taxi clearances via ATC voice speed commands or datal ink; and, Availability of flight deck display algorithms to reduce STBO RTA error. Flight Deck Implications. Pilot RTA conformance for STBO clearances, in the form of ATC taxi clearances with associated speed requirements, was found to be relatively poor, unless the pilot is required to follow a precise speed and acceleration/deceleration profile. However, following such a precise speed profile results in inordinate head-down tracking of current ground speed, leading to potentially unsafe operations. Mitigating these results, and providing good taxi RTA performance without the associated safety issues, is a flight deck avionics or electronic flight bag (EFB) solution. Such a solution enables pilots to meet the taxi route RTA without moment-by-moment tracking of ground speed. An avionics or EFB "error-nulling" algorithm allows the pilot to view the STBO information when the pilot determines it is necessary and when workload alloys, thus enabling the pilot to spread his/her attention appropriately and strategically on aircraft separation airport navigation, and the many other flight deck tasks concurrently required

The vascular neural network—a new paradigm in stroke pathophysiology

PubMed Central

Zhang, John H.; Badaut, Jerome; Tang, Jiping; Obenaus, Andre; Hartman, Richard; Pearce, William J.

2013-01-01

The concept of the neurovascular unit as the key brain component affected by stroke is controversial, because current definitions of this entity neglect mechanisms that control perfusion and reperfusion of arteries and arterioles upstream of the cerebral microcirculation. Indeed, although definitions vary, many researchers consider the neurovascular unit to be restricted to endothelial cells, neurons and glia within millimetres of the cerebral capillary microcirculation. This Perspectives article highlights the roles of vascular smooth muscle, endothelial cells and perivascular innervation of cerebral arteries in the initiation and progression of, and recovery from, ischaemic stroke. The concept of the vascular neural network—which includes cerebral arteries, arterioles, and downstream neuronal and glial cell types and structures—is introduced as the fundamental component affected by stroke pathophysiology. The authors also propose that the vascular neural network should be considered the main target for future therapeutic intervention after cerebrovascular insult. PMID:23070610

Imaging of hemifacial spasm.

PubMed

Hermier, M

2018-04-25

Almost all primary hemifacial spasms are associated with one or more neurovascular conflicts, most often at the root exit zone in the immediate vicinity of the brainstem. Imaging has first to exclude a secondary hemifacial spasm and secondly to search for and characterize the responsible neurovascular conflict(s). Magnetic resonance imaging should include high-resolution anatomical hyper T2-weighted sequences and magnetic resonance angiography by using 1.5 or even better 3 Tesla magnets. The most frequent vascular compressions are from the anterior-inferior cerebellar artery, the posterior-inferior cerebellar artery and the vertebrobasilar artery; venous conflicts are very rare. Conflicts are often multiple; also, the same vessel may compress the facial nerve in two places. Also, conflicts may be aided by particular anatomical circumstances, including arterial dolichoectasia, posterior fossa with a small volume or bony malformations. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Ontogeny of con A and PHA responses of chicken blood cells in MHC-compatible lines 6(3) and 7(2).

PubMed

Fredericksen, T L; Gilmour, D G

1983-06-01

The development of T cell responsiveness to Con A and PHA was examined in two MHC-compatible inbred chicken lines, RPRL 6(3) and 7(2), at ages 2 to 118 days posthatching. These lines are respectively resistant or susceptible to Marek's disease, a naturally occurring, virally induced T cell lymphoma. Between-line comparisons were made of optimal in vitro responses of diluted serum-free blood cells to each mitogen in two groups of chicks tested over ages 2 to 63 and 41 to 118 days. Over 2 to 63 days, Con A responses increased with age at the same rate in each line, but 7(2) responses averaged 2.3 times higher than 6(3). The increase with age was dependent on blood lymphocyte counts, which also increased with age in parallel in both lines. In contrast, the between-line difference in responsiveness was dependent on intrinsic reactivity of cells as well as lymphocyte counts. Covariance analysis was used to estimate that line 7(2) was 1.4 times higher than 6(3) in intrinsic cell reactivity, after accounting for the effect of the twofold higher blood lymphocyte counts in 7(2), and that this intrinsic difference contributed almost one-half the total difference. Over 41 to 118 days Con A responses no longer increased with age, although lymphocyte counts were still increasing, and the line difference (2.6 times) was now almost entirely contributed by a 2.3-fold superiority of 7(2) blood cells in intrinsic reactivity. The line difference in PHA responses was the reverse of the above in young chicks, with 6(3) responses greater than 7(2) in spite of lower lymphocyte counts. In additional chicks tested over 5 to 26 days, intrinsic reactivity of 6(3) cells to PHA averaged 4.5 times higher than 7(2). There was an abrupt decline in intrinsic reactivity of line 6(3) blood cells between 26 and 41 days to a level equal with 7(2). After this age, line 7(2) responses were 1.8 times greater than those of 6(3), and this difference was dependent solely on lymphocyte count differences. The

The InterCon network: a program for education partnerships at the University of Texas-Houston Health Science Center.

PubMed

Castro, G A; Bouldin, P A; Farver, D W; Maugans, L A; Sanders, L C; Booker, J

1999-04-01

The University of Texas-Houston Health Science Center (UT-Houston) has created programs and activities to address the state's pressing needs in minority education. Through InterCon, a network of universities and K-12 schools, UT-Houston works with its partners to identify competitive candidates in the current pool of minority graduates with bachelor's degrees and to help them--along with their non-minority counterparts--progress in their education. Another objective is to expand the pool of minorities underrepresented in medicine who complete high school and go to college. In 1994 UT-Houston and Prairie View A&M University created a collaborative venture to provide new educational opportunities at UT-Houston for Prairie View's predominantly African American students. A three-track summer internship program--a result of that collaboration--has since been expanded to partnerships with other minority and majority universities throughout Texas. In 1998, for example, 108 undergraduate students from these universities (and 40 other universities nationwide) participated in research, professional, and administrative summer internships at UT-Houston. The InterCon network also has partnerships with K-12 schools. UT-Houston works with inner-city, suburban, and rural school districts to develop education models that can be transferred throughout the state. The partnerships deal with helping to teach basic academic skills and computer literacy, improve science-related instruction, meet demands for health promotion materials and information for school-initiated health and wellness programs, and develop distance-learning paradigms. UT-Houston views InterCon as a program helping Texas institutions to engage and adapt to the socioeconomic factors, demographic changes, and technology explosion that currently challenge public education.

Surgical anatomy of the lower trapezius tendon transfer.

PubMed

Omid, Reza; Cavallero, Matthew J; Granholm, Danielle; Villacis, Diego C; Yi, Anthony M

2015-09-01

The precise surgical anatomy of the lower trapezius tendon transfer has not been well described. A precise anatomic description of the different trapezius segments and the associated neurovascular structures is crucial for operative planning and execution. We aimed (1) to establish a reliable demarcation between the middle and lower trapezius, (2) to establish the precise relationship of the main neurovascular pedicle to the muscle belly, and (3) to evaluate the utility of the relationships established in (1) and (2) by using the results of this study to perform cadaveric lower trapezius tendon harvest. In phase 1, a single surgeon performed all measurements using 10 cadavers. In phase 2, 10 cadaveric shoulders were used to harvest the tendon by using the relationships established in phase 1. We found anatomically distinct insertion sites for the lower and middle trapezius. The lower trapezius inserted at the scapular spine dorsum and the middle trapezius inserted broadly along the superior surface of the scapular spine. The distance from tip of tendon insertion to the nearest nerve at the most superior portion of the lower trapezius was 58 mm (standard deviation ± 18). By use of these relationships, there were no cases of neurovascular injury during our cadaveric tendon harvests. The lower trapezius can be reliably and consistently identified without violating fibers of the middle trapezius. Muscle splitting can be performed safely without encountering the spinal accessory nerve (approximately 2 cm medial to the medial scapular border). Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Intrafascial nerve-sparing endoscopic extraperitoneal radical prostatectomy.

PubMed

Stolzenburg, Jens-Uwe; Rabenalt, Robert; Do, Minh; Schwalenberg, Thilo; Winkler, Mathias; Dietel, Anja; Liatsikos, Evangelos

2008-05-01

Based on our recently published anatomic studies, we present the most recent refinement of the endoscopic extraperitoneal radical prostatectomy (EERPE), the intrafascial nerve-sparing EERPE (nsEERPE). As part of the intrafascial technique, the dissection plane is directly on the prostatic capsule, freeing the prostate laterally from its thin surrounding fascia that contains small vessels and nerves. The technique enables puboprostatic ligament preservation, leaving intact endopelvic fascia, periprostatic fascia, and neurovascular bundles. The operation was performed in 150 patients with indications for nerve-sparing procedure. The mean operative time was 131 min (range: 50-210 min) and the mean catheterization time was 5.9 d (range: 4-20 d). Twelve months postoperatively, 94.3% of the patients were continent (no need for pads), 4.6% had minimal stress incontinence, and one patient required >2 pads/d. At the 12-mo follow-up, the potency rates (erections sufficient for intercourse with or without the use of phosphodiesterase 5 [PDE5] inhibitors) of the patients who underwent bilateral intrafascial nsEERPE were 89.7% (age: 44-55 yr), 81.1% (age: 56-65 yr), and 61.9% (age: >65 yr). Positive surgical margins in pT2 and pT3 tumors were 4.5% and 29.4%, respectively. The intrafascial nsEERPE enables the dissection of the prostate with limited trauma to the surrounding fascias and the enclosed neurovascular bundles. We propose that the preserved neurovascular bundles with intrafascial nsEERPE are more viable. The results advocate this proposition.

Majewski osteodysplastic primordial dwarfism type II (MOPD II): expanding the vascular phenotype.

PubMed

Bober, Michael B; Khan, Nadia; Kaplan, Jennifer; Lewis, Kristi; Feinstein, Jeffrey A; Scott, Charles I; Steinberg, Gary K

2010-04-01

Majewski Osteodysplastic Primordial Dwarfism, Type II (MOPD II) is a rare, autosomal recessive disorder. Features include severe intrauterine growth retardation (IUGR), poor postnatal growth (adult stature approximately 100 cm), severe microcephaly, skeletal dysplasia, characteristic facial features, and normal or near normal intelligence. An Institutional Review Board (IRB) approved registry was created and currently follows 25 patients with a diagnosis of MOPD II. Based on previous studies, a neurovascular screening program was implemented and 13 (52%) of these patients have been found to have cerebral neurovascular abnormalities including moyamoya angiopathy and/or intracranial aneurysms. The typical moyamoya pathogenesis begins with vessel narrowing in the supraclinoid internal carotid artery, anterior cerebral (A1) or middle cerebral (M1) artery segments. The narrowing may predominate initially on one side, progresses to bilateral stenosis, with subsequent occlusion of the vessels and collateral formation. We present four patients who, on neurovascular screening, were found to have cerebrovascular changes. Two were asymptomatic, one presented with a severe headache and projectile vomiting related to a ruptured aneurysm, and one presented after an apparent decline in cognitive functioning. Analysis of the registry suggests screening for moyamoya disease be performed at the time of MOPD II diagnosis and at least every 12-18 months using MRA or computerized tomographic angiography (CTA). We believe this is imperative. If diagnosed early enough, re-vascularization and aneurysm treatment in skilled hands can be performed safely and prevent or minimize long-term sequelae in this population. Emergent evaluation is also needed when other neurologic or cardiac symptoms are present. (c) 2010 Wiley-Liss, Inc.

Exendin-4 inhibits high-altitude cerebral edema by protecting against neurobiological dysfunction

PubMed Central

Sun, Zhong-Lei; Jiang, Xian-Feng; Cheng, Yuan-Chi; Liu, Ying-Fu; Yang, Kai; Zhu, Shuang-Long; Kong, Xian-Bin; Tu, Yue; Bian, Ke-Feng; Liu, Zhen-Lin; Chen, Xu-Yi

2018-01-01

The anti-inflammatory and antioxidant effects of exendin-4 (Ex-4) have been reported previously. However, whether (Ex-4) has anti-inflammatory and antioxidant effects on high-altitude cerebral edema (HACE) remains poorly understood. In this study, two rat models of HACE were established by placing rats in a hypoxic environment with a simulated altitude of either 6000- or 7000-m above sea level (MASL) for 72 hours. An altitude of 7000 MASL with 72-hours of hypoxia was found to be the optimized experimental paradigm for establishing HACE models. Then, in rats where a model of HACE was established by introducing them to a 7000 MASL environment with 72-hours of hypoxia treatment, 2, 10 and, 100 μg of Ex-4 was intraperitoneally administrated. The open field test and tail suspension test were used to test animal behavior. Routine methods were used to detect change in inflammatory cells. Hematoxylin-eosin staining was performed to determine pathological changes to brain tissue. Wet/dry weight ratios were used to measure brain water content. Evans blue leakage was used to determine blood-brain barrier integrity. Enzyme-linked immunosorbent assay (ELISA) was performed to measure markers of inflammation and oxidative stress including superoxide dismutase, glutathione, and malonaldehyde values, as well as interleukin-6, tumor necrosis factor-alpha, cyclic adenosine monophosphate levels in the brain tissue. Western blot analysis was performed to determine the levels of occludin, ZO-1, SOCS-3, vascular endothelial growth factor, EPAC1, nuclear factor-kappa B, and aquaporin-4. Our results demonstrate that Ex-4 preconditioning decreased brain water content, inhibited inflammation and oxidative stress, alleviated brain tissue injury, maintain blood-brain barrier integrity, and effectively improved motor function in rat models of HACE. These findings suggest that Ex-4 exhibits therapeutic potential in the treatment of HACE. PMID:29722317

77 FR 7589 - Neurological Devices Panel of the Medical Devices Advisory Committee; Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-13

... current knowledge about the safety and effectiveness of the Wingspan Stent System with Gateway PTA Balloon... premarket and postmarket data. The Wingspan Stent System with Gateway PTA Balloon Catheter is a neurovascular stent, balloon catheter, and delivery system consisting of the following components: 1. Wingspan...

"Estudio tribologico de aceros para moldes. Aplicacion al moldeo por inyeccion de polibutilentereftalato reforzado con fibra de vidrio"

NASA Astrophysics Data System (ADS)

Martinez Mateo, Isidoro Jose

fabricacion del molde, tienen una gran influencia sobre su comportamiento en servicio a lo largo de la vida util del molde. En la primera parte del presente estudio, a partir de ensayos punzon sobre disco, se ha determinado la relacion entre la resistencia al desgaste y la dureza de aceros para moldes obtenidos a partir de bloques de gran espesor, estudiando los principales mecanismos de desgaste que tienen lugar. A continuacion, con el fin de determinar el dano superficial que sufren los aceros para moldes en condiciones reales de inyeccion, se han estudiado distintos tipos de aceros utilizados comercialmente en moldes de inyeccion de polimeros y materiales compuestos, seleccionando las condiciones de operacion para determinar la variacion de la rugosidad superficial del acero en funcion del material inyectado, del numero de operaciones sucesivas de inyeccion y de la orientacion del flujo de inyeccion, mediante tecnicas de perfilometria optica y microscopia electronica de barrido. Ademas del dano superficial sufrido por el acero con el numero de piezas inyectadas, tambien se ha determinado la evolucion de la rugosidad superficial de los materiales inyectados, polibutilentereftalato (PBT) puro y materiales compuestos derivados de PBT por adicion de un 20 o un 50% en peso de fibra de vidrio. En el caso de las piezas inyectadas, se ha caracterizado su microestructura en funcion del flujo de inyeccion y de la densidad de fibra, se han determinado sus propiedades termicas y dinamico-mecanicas, asi como la variacion de la rugosidad superficial de las piezas inyectadas con el numero de operaciones de inyeccion y con la geometria de las distintas secciones de las piezas. Finalmente, se ha evaluado la resistencia a la abrasion de PBT reforzado con un 50% de fibra, en funcion del numero de piezas inyectadas y de la direccion de rayado con respecto a la orientacion del flujo de inyeccion.

Laparoscopy for inflammatory bowel disease: pros and cons.

PubMed

Sardinha, T C; Wexner, S D

1998-04-01

The role of laparoscopic surgery in the treatment of colorectal malignancies is still under investigation, although it can offer significant benefits to many patients with inflammatory bowel disease (IBD). The aim of this study was to assess the pros and cons of the laparoscopic management of IBD. Data were obtained from a review of the literature published since 1992, when the first report of laparoscopic surgery for IBD appeared in print. From 1992 to 1997 several series of laparoscopic colorectal surgery for the management of IBD have been reported. A close evaluation of these studies revealed that laparoscopy in patients with terminal ileal Crohn's disease or anal Crohn's disease in need of fecal diversion offers significant advantages compared to laparotomy, including decreased pain, length of hospitalization, and disability. An additional bonus is improved cosmesis and a reduction in symptomatic postoperative adhesions. These many benefits can be achieved without any increase in morbidity or expense. Conversely, the use of this technology for restorative proctocolectomy in patients with mucosal ulcerative colitis is associated with a longer operative time and an increased incidence of both intra- and postoperative complications compared to laparotomy. Laparoscopic colorectal surgery can thus be advantageous for treatment of terminal ileal Crohn's disease but cannot be routinely justified for the treatment of mucosal ulcerative colitis.

Uso de Sustancias en Mujeres con Desventaja Social: Riesgo para el Contagio de VIH/SIDA

PubMed Central

Cianelli, R.; Ferrer, L; Bernales, M.; Miner, S.; Irarrázabal, L.; Molina, Y.

2009-01-01

Antecedentes La caracterización epidemiológica en Chile apunta a feminización, pauperización y heterosexualización de la epidemia del VIH, lo que implica un mayor riesgo para las mujeres en desventaja social. Si a esto se suma la utilización de sustancias, la vulnerabilidad de este grupo frente al VIH/SIDA aumenta. Objetivo Describir el uso de sustancias en mujeres con desventaja social e identificar factores de riesgo de contagio de VIH, asociados a este consumo. Material y Método 52 mujeres fueron entrevistadas como parte del proyecto “Testeando una intervención en prevención de VIH/SIDA en mujeres chilenas” GRANT # RO1 TW 006977. Se describen variables sociodemográficas y de consumo de sustancias a través de estadísticas descriptivas y se analiza la relación entre variables a través de pruebas de correlación. Resultados Los resultados indican un perfil sociodemográfico que sitúa a las mujeres en situación de vulnerabilidad frente al contagio de VIH/SIDA, con alto índice de uso de sustancias que acentúa el riesgo. Conclusiones Los hallazgos apuntan a la necesidad de considerar intervenciones que se enfoquen en la prevención de VIH en mujeres, abordando los riesgos asociados al consumo de sustancias. PMID:21197380

Síndrome de Grisel en el adulto e inestabilidad cráneo cervical. Odontoidectomía endoscópica transnasal y fijación occípito-cervical. Reporte de caso y revisión de literatura

PubMed Central

Herrera, Roberto; Rojas, Héctor; Estramian, Ariel; Gómez, Julieta; Ledesma, José Luis; Pablo, José; Pastore, Julián

2018-01-01

Resumen Introducción: La patología de la unión cráneo-cervical es poco frecuente en la práctica neuroquirúrgica diaria. En general la mayor parte de estas lesiones son de origen traumático o reumatológico. La inestabilidad atlanto-axial de origen inflamatorio (Síndrome de Grisel) es una rara entidad de la que solo se han reportado 16 casos adultos en la literatura. Esta patología se caracteriza por el desarrollo de una lesión osteolítica a nivel de la articulación atlanto-axoidea posterior a un evento infeccioso, generalmente de las vías aéreas superiores. Descripción del caso: Presentamos el caso de una paciente de 76 años quien concurre en consulta por un cuadro clínico de inestabilidad cráneo espinal secundaria a una lesión osteolítica, con compromiso de C1 y C2. La sintomatología comenzó posteriormente a un proceso infeccioso respiratorio. Se realizó una fijación occípito-cervical posterior y una Odontoidectomía con descompresión anterior por vía endoscópica transnasal. La paciente evolucionó con resolución completa de los síntomas. Los cultivos fueron negativos y el estudio de anatomía patológica concluyó cambios inflamatorios inespecíficos. Conclusión: Hasta hace algunos pocos años la única opción para abordar esta patología era la vía transoral con técnica microquirúrgica. Hoy en día la endoscopía nos brinda muchas ventajas técnicas por lo que constituye una opción a tener en cuenta en la planificación de los abordajes a la unión cráneo-cervical. PMID:29430326

Medición de placas astrométricas obtenidas con el telescopio Astrográfico de La Plata

NASA Astrophysics Data System (ADS)

di Sisto, R. P.; Orellana, R.

El Observatorio de La Plata cuenta con un gran número de placas de asteroides y cometas obtenidas con el telescopio astrográfico, que cubren gran parte del cielo del hemisferio sur. En 1996 se recopilaron y clasificaron 2187 placas (Beca para estudiantes de la AAA 1996) de las cuales 2031 corresponden a asteroides. Los datos de cada placa se volcaron en una base de datos creada para facilitar su manejo y preservar la información. A partir de este trabajo se revisaron los MPC electrónicos y se identificaron aquellas placas de asteroides pertenecientes a nuestra base de datos cuyos resultados no fueron publicados en los mismos. De un total de 400 placas que no aparecían publicadas sobresalía un paquete constituído por 40 placas obtenidas en 1977. Estas últimas fueron reducidas utilizando las posiciones y movimientos propios de las estrellas de referencia obtenidas del catálogo SAO 2000 dadas para el sistema FK5. Las posiciones calculadas fueron enviadas y publicadas en los Minor Planet Circulars (MPC).

Application of basic principles of physics to head and neck MR angiography: troubleshooting for artifacts.

PubMed

Pandey, Shilpa; Hakky, Michael; Kwak, Ellie; Jara, Hernan; Geyer, Carl A; Erbay, Sami H

2013-05-01

Neurovascular imaging studies are routinely used for the assessment of headaches and changes in mental status, stroke workup, and evaluation of the arteriovenous structures of the head and neck. These imaging studies are being performed with greater frequency as the aging population continues to increase. Magnetic resonance (MR) angiographic imaging techniques are helpful in this setting. However, mastering these techniques requires an in-depth understanding of the basic principles of physics, complex flow patterns, and the correlation of MR angiographic findings with conventional MR imaging findings. More than one imaging technique may be used to solve difficult cases, with each technique contributing unique information. Unfortunately, incorporating findings obtained with multiple imaging modalities may add to the diagnostic challenge. To ensure diagnostic accuracy, it is essential that the radiologist carefully evaluate the details provided by these modalities in light of basic physics principles, the fundamentals of various imaging techniques, and common neurovascular imaging pitfalls. ©RSNA, 2013.

Anatomical relations of anterior and posterior ankle arthroscopy portals: a cadaveric study.

PubMed

Oliva, Xavier Martin; Méndez López, José Manuel; Monzo Planella, Mariano; Bravo, Alex; Rodrigues-Pinto, Ricardo

2015-04-01

Ankle arthroscopy is an increasingly used technique. Knowledge of the anatomical structures in relation to its portals is paramount to avoid complications. Twenty cadaveric ankles were analysed to assess the distance between relevant neurovascular structures to the anteromedial, anterolateral, posteromedial, and posterolateral arthroscopy portals. The intermediate dorsal branch of the superficial peroneal nerve was the closest structure to any of the portals (4.8 mm from the anterolateral portal), followed by the posterior tibial nerve (7.3 mm from the posteromedial portal). All structures analysed but one (posterior tibial artery) were, at least in one specimen, <5 mm distant from one of the portals. This study provides information on the anatomical relations of ankle arthroscopy portals and relevant neurovascular structures, confirming previous studies identifying the superficial peroneal nerve as the structure at highest risk of injury, but also highlighting some important variations. Techniques to minimise the injury to these structures are discussed.

Thoracic outlet syndrome: a controversial clinical condition. Part 1: anatomy, and clinical examination/diagnosis

PubMed Central

Hooper, Troy L; Denton, Jeff; McGalliard, Michael K; Brismée, Jean-Michel; Sizer, Phillip S

2010-01-01

Thoracic outlet syndrome (TOS) is a frequently overlooked peripheral nerve compression or tension event that creates difficulties for the clinician regarding diagnosis and management. Investigators have categorized this condition as vascular versus neurogenic, where vascular TOS can be subcategorized as either arterial or venous and neurogenic TOS can subcategorized as either true or disputed. The thoracic outlet anatomical container presents with several key regional components, each capable of compromising the neurovascular structures coursing within. Bony and soft tissue abnormalities, along with mechanical dysfunctions, may contribute to neurovascular compromise. Diagnosing TOS can be challenging because the symptoms vary greatly amongst patients with the disorder, thus lending to other conditions including a double crush syndrome. A careful history and thorough clinical examination are the most important components in establishing the diagnosis of TOS. Specific clinical tests, whose accuracy has been documented, can be used to support a clinical diagnosis, especially when a cluster of positive tests are witnessed. PMID:21655389

In vivo optical activation of astrocytes as a potential therapeutic strategy for neurodegenerative diseases

NASA Astrophysics Data System (ADS)

Chen, Yuanxin; Mancuso, James; Zhao, Zhen; Li, Xuping; Xue, Zhong; Wong, Stephen T. C.

2013-03-01

Neurovascular dysfunction in many neurodegenerative diseases, such as Alzheimer's disease (AD), reduces blood flow to affected brain areas and causes neuronal dysfunction and loss. A new optical imaging technique is developed to activate astrocytes in live animal models in order to investigate the increase of local cerebral blood flow as a potential therapeutic strategy for AD. The technique uses fluorescent labeling of vasculature and astrocytes coupled with intravital 2-photon microscopy to visualize the astrocyte-vasculature interactions in live animals. Using femtosecond laser stimulation, calcium uncaging is applied to specifically target and activate astrocytes in vivo with high spatial and temporal resolutions. Intravital 2-photon microscopy imaging was employed to demonstrate that single endfoot optical activation around an arteriole induced a 25% increase in arteriole diameter, which in turn increased cerebral local blood flow in down-stream capillaries. This quantitative result indicates the potential of using optical activation of astrocytes in afflicted brain areas of neurodegeneration to restore normal neurovascular functions.

Knee flexion deformity from poliomyelitis treated by supracondylar femoral extension osteotomy.

PubMed

de Moraes Barros Fucs, Patricia M; Svartman, Celso; de Assumpção, Rodrigo Montezuma César

2005-12-01

Between April 1979 and August 1993, we treated 39 patients (49 knees) with knee flexion deformity after Poliomyelitis. All were subjected to fractional hamstring lengthening and supracondylar femoral extension osteotomy in the same surgical procedure. The goal was to correct the deformity and fit the lower extremities in long braces to improve or promote gait. Patients' mean age was 19.5 (6.5-39) years and the mean knee flexion deformity was 65 degrees (24-158 degrees). The mean follow-up was 15.5 (11.5-25) years. Postoperatively, 22 knees had full extension, in 26 there was an extension lag between -1 and -10 degrees and in one a lag greater than 10 degrees. There were no neurovascular complications and all patients were fitted with long leg braces. Surgical planning is important, especially in severe deformities, where shortening of the femur is necessary to facilitate the osteotomy and relax the neurovascular structures.

Violación del Principio de Equivalencia en Teorías con Dilatón de Cuerdas

NASA Astrophysics Data System (ADS)

Landau, S. J.; Sisterna, P. D.; Vucetich, H.

Se estudian las violaciones al Principio de Equivalencia en Teorías con Dilatón de Cuerdas. En estos modelos, algunas de las constantes fundamentales dependen del espacio y del tiempo. Se muestra que los experimentos de caída libre no tienen aún precisión como para poner límites a los parámetros de la teoría.

Presentación del estudio "Links" de hombres que tienes sexo con hombres en Buenos Aires, Argentina.

PubMed

Carballo-Diéguez, Alex; Avila, María M; Balán, Iván C; Marone, Rubén; Pando, María A; Barreda, Victoria

2011-03-01

Estudios previos en Buenos Aires reportaron altas prevalencias de HIV entre HSH, con valores que oscilan entre 9 y 14% durante casi 10 años de continuo testeo. El objetivo principal de este estudio fue la evaluación de factores relacionados al comportamiento de alto riesgo para transmisión del HIV entre HSH entre los que se incluyen el conocimiento y factores emocionales, socioculturales y ambientales. Por otro lado se realizó la estimación de prevalencia e incidencia de HIV utilizando RDS (Respondent Driven Sampling), así como la presencia de otras infecciones de transmisión sexual. Por último se evaluaron los hábitos de testeo para HIV indagando que factores facilitan o impiden su realización. El estudio constó de dos fases, en primer lugar una fase cualitativa y posteriormente una fase cuantitativa con una duración total de 4 años y medio. Durante la fase cualitativa se realizaron 44 entrevistas individuales en profundidad, 8 grupos focales y 10 observaciones etnográficas (hoteles, baños públicos ("teteras"), cines pornográficos, fiestas privadas, dark rooms y discotecas). Durante la fase cuantitativa del estudio se realizó el reclutamiento de 500 participantes que provinieron de la Ciudad Autónoma de Buenos Aires, así como del Gran Buenos Aires. El reclutamiento se comenzó con 16 participantes llamados semillas. Se realizó el diagnóstico de infección por HIV, hepatitis B y C (HBV y HCV), Treponema pallidum, Virus Papiloma Humano (HPV) y Chlamidias. La colaboración establecida entre los grupos de trabajo enfocados en áreas diversas posibilitó el abordaje conjunto de nuevas estrategias de investigación antes no exploradas en nuestro país. Los resultados más relevantes de esta investigación serán progresivamente publicados en sucesivos números de Actualizaciones en SIDA.

Identification of nucleotides in the 5'UTR and amino acids substitutions that are essential for the infectivity of 5'UTR-NS5A recombinant of hepatitis C virus genotype 1b (strain Con1).

PubMed

Li, Jinqian; Feng, Shengjun; Liu, Xi; Guo, Mingzhe; Chen, Mingxiao; Chen, Yiyi; Rong, Liang; Xia, Jinyu; Zhou, Yuanping; Zhong, Jin; Li, Yi-Ping

2018-05-01

Genotype 1b strain Con1 represents an important reference in the study of hepatitis C virus (HCV). Here, we aimed to develop an advanced infectious Con1 recombinant. We found that previously identified mutations A1226G/F1464L/A1672S/Q1773H permitted culture adaption of Con1 Core-NS5A (C-5A) recombinant containing 5'UTR and NS5B-3'UTR from JFH1 (genotype 2a), thus acquired additional mutations L725H/F886L/D2415G. C-5A containing all seven mutations (C-5A_7m) replicated efficiently in Huh7.5 and Huh7.5.1 cells and had an increased infectivity in SEC14L2-expressing Huh7.5.1 cells. Incorporation of Con1 NS5B was deleterious to C-5A_7m, however Con1 5'UTR was permissive but attenuated the virus. Nucleotides G1, A4, and G35 primarily accounted for the viral attenuation without affecting RNA translation. C-5A_7m was inhibited dose-dependently by simeprevir and daclatasvir, and substitutions at A4, A29, A34, and G35 conferred resistance to miR-122 antagonism. The novel Con1 5'UTR-NS5A recombinant, adaptive mutations, and critical nucleotides described here will facilitate future studies of HCV culture systems and virus-host interaction. Copyright © 2018 Elsevier Inc. All rights reserved.

Interpretacion y Biomecanica. Hoja de consejos de PEPNet (Interpreting and Biomechanics. PEPNet Tipsheet)

ERIC Educational Resources Information Center

DeGroote, Bill; Morrison, Carolyn

2010-01-01

This publication, written in Spanish, describes cumulative trauma disorder (CTD), which refers to a collection of disorders associated with nerves, muscles, tendons, bones, and the neurovascular (nerves and related blood vessels) system. CTD symptoms may involve the neck, back, shoulders, arms, wrists, or hands. Interpreters with CTD may…

Interpreting & Biomechanics. PEPNet Tipsheet

ERIC Educational Resources Information Center

PEPNet-Northeast, 2001

2001-01-01

Cumulative trauma disorder (CTD) refers to a collection of disorders associated with nerves, muscles, tendons, bones, and the neurovascular (nerves and related blood vessels) system. CTD symptoms may involve the neck, back, shoulders, arms, wrists, or hands. Interpreters with CTD may experience a variety of symptoms including: pain, joint…

Preparation of stimulus responsive multiple emulsions by membrane emulsification using con a as biochemical sensor.

PubMed

Piacentini, Emma; Drioli, Enrico; Giorno, Lidietta

2011-04-01

In this work, a novel strategy for the controlled fabrication of biomolecular stimulus responsive water-in-oil-in-water (W/O/W) multiple emulsion using the membrane emulsification process was investigated. The emulsions interface was functionalized with a biomolecule able to function as a receptor for a target compound. The interaction between the biomolecular receptor and target stimulus activated the release of bioactive molecules contained within the structured emulsion. A glucose sensitive emulsion was investigated as a model study case. Concanavalin A (Con A) was used as the biomolecular glucose sensor. Various physicochemical strategies for stimulus responsive materials formulation are available in literature, but the preparation of biomolecule-responsive emulsions has been explored for the first time in this paper. The development of novel drug delivery systems requires advanced and highly precise techniques to obtain their particular properties and targeting requirements. The present study has proven the flexibility and suitability of membrane emulsification for the preparation of stable and functional multiple emulsions containing Con A as interfacial biomolecular receptor able to activate the release of a bioactive molecule as a consequence of interaction with the glucose target molecule. The influence of emulsion interfacial composition and membrane emulsification operating conditions on droplets stability and functional properties have been investigated. The release of the bioactive molecule as a function of glucose stimulus and its concentration has been demonstrated. Copyright © 2010 Wiley Periodicals, Inc.

[Not Available].

PubMed

Díaz, Toni; Ficapal-Cusí, Pilar; Aguilar-Martínez, Alicia

2016-07-19

Introducción: a pesar de la relevancia nutricional del desayuno para el desarrollo y su asociación a un mejor aprendizaje y rendimiento escolar, numerosos estudios ponen en evidencia que en muchos casos se omite o se hace mal.Objetivo: determinar la calidad del desayuno de estudiantes de entre 10 y 16 años con intención de determinar en qué momento sería conveniente realizar programas educativos sobre la importancia de esta comida y cómo mejorar su calidad.Método: estudio observacional, descriptivo y transversal a partir de un cuestionario con preguntas cerradas acerca de los hábitos de alimentación en el desayuno en estudiantes de educación primaria y secundaria.Resultados y conclusión: solo el 18,5% de los estudiantes realiza un desayuno de buena calidad y su mala calidad va aumentando progresivamente con los cursos y se asocia al hecho de desayunar solo. En ambos niveles educativos los alimentos más consumidos en casa pertenecen al grupo de los lácteos y los cereales, mientras que en el centro escolar, el bocadillo resulta el desayuno más habitual; no obstante se observan diferencias entre primaria y secundaria en cuanto al consumo de fruta y bebidas azucaradas, entre otros.Conclusión: sería interesante valorar la instauración de programas de desayuno escolar incluyendo en ellos no solo a estudiantes de primaria, sino también, y especialmente, a adolescentes pues son estos quienes omiten esta comida en mayor proporción. Las intervenciones deberían orientarse a corregir las desviaciones más habituales observadas en cada uno de los niveles educativos.

Is ACPA positivity the main driver for rheumatoid arthritis treatment? Pros and cons.

PubMed

Alivernini, Stefano; Galeazzi, Mauro; Peleg, Hagit; Tolusso, Barbara; Gremese, Elisa; Ferraccioli, Gianfranco; Naparstek, Yaakov

2017-11-01

Rheumatoid Arthritis (RA) is an autoimmune chronic disease that is characterized by the positivity of various antibodies, the most specific being autoantibodies against citrullinated antigens (ACPA). Despite ACPA are not arthritogenic by themselves, ACPA positive individuals have high risk of RA development and ACPA positivity is associated with severe erosive phenotype and higher mortality rate compared to seronegative RA. Moreover, ACPA status is associated with favorable response to biologics targeting pathways involving autoantibody producing cells as B lymphocytes. In the current review we have discussed the pros and cons on the available scientific evidences, regarding the diagnostic, prognostic and management implications of ACPAs in RA. Copyright © 2017 Elsevier B.V. All rights reserved.

Anatomy of the psoas muscle and lumbar plexus with respect to the surgical approach for lateral transpsoas interbody fusion.

PubMed

Kepler, Christopher K; Bogner, Eric A; Herzog, Richard J; Huang, Russel C

2011-04-01

Lateral transpsoas interbody fusion (LTIF) is a minimally invasive technique that permits interbody fusion utilizing cages placed via a direct lateral retroperitoneal approach. We sought to describe the locations of relevant neurovascular structures based on MRI with respect to this novel surgical approach. We retrospectively reviewed consecutive lumbosacral spine MRI scans in 43 skeletally mature adults. MRI scans were independently reviewed by two readers to identify the location of the psoas muscle, lumbar plexus, femoral nerve, inferior vena cava and right iliac vein. Structures potentially at risk for injury were identified by: a distance from the anterior aspect of the adjacent vertebral bodies of <20 mm, representing the minimum retraction necessary for cage placement, and extension of vascular structures posterior to the anterior vertebral body, requiring anterior retraction. The percentage of patients with neurovascular structures at risk for left-sided approaches was 2.3% at L1-2, 7.0% at L2-3, 4.7% at L3-4 and 20.9% at L4-5. For right-sided approaches, this rose to 7.0% at L1-2, 7.0% at L2-3, 9.3% at L3-4 and 44.2% at L4-5, largely because of the relatively posterior right-sided vasculature. A relationship between the position of psoas muscle and lumbar plexus is described which allows use of the psoas position as a proxy for lumbar plexus position to identify patients who may be at risk, particularly at the L4-5 level. Further study will establish the clinical relevance of these measurements and the ability of neurovascular structures to be retracted without significant injury.

What to consider when regulating electronic cigarettes: Pros, cons and unintended consequences.

PubMed

Caponnetto, Pasquale; Saitta, Daniela; Sweanor, David; Polosa, Riccardo

2015-06-01

Many public health experts, medical research societies, large health organizations and policy makers have expressed concerns about the increased popularity of electronic cigarettes and have pushed for more restrictive measures ranging from complete bans to tight regulations of these products either as medicines or as tobacco products. But these concerns have never been adequately qualified nor quantified. Without judicious assessment and thorough evaluation, regulations may have unintended consequences that can do more damage than good in public health terms. In this article, we will appraise the existing prominent regulatory frameworks for e-cigarettes, namely, general consumer product, medicinal product and tobacco product regulation, to highlight their pros and cons. Moreover, we provide concrete examples of the unintended consequences which may arise from inappropriate regulatory action. Copyright © 2015 Elsevier B.V. All rights reserved.

The pros and cons about the digital recording of Intangible Cultural Heritage and some strategies

NASA Astrophysics Data System (ADS)

Yang, H.

2015-08-01

Intangible Cultural Heritage (referred to as ICH), whose fundamental nature different from the tangible cultural heritage is "Intangible", and the related physical presence of the heritage is not the core content. Digital means have irreplaceable advantages in recording intangible and dynamic ICH resources, while it also needs flexible and rigorous recording means as a support, thus striving to maximize resources recording and protection. This article will focus on the pros and cons about the digital recording of ICH, and preliminarily discuss some strategies used in the process of recording.

Evolución de planetas gigantes y posibilidades de su detección directa

NASA Astrophysics Data System (ADS)

Brunini, A.; Benvenuto, O. G.

Desde la reciente detección de planetas gigantes orbitando estrellas cercanas de tipo solar por medio de efecto Doppler, uno de los principales problemas, en cuanto al estudio de los sistemas planetarios extrasolares, se refiere a la posibilidad de obtener evidencia directa de su existencia. Esto parece ser factible gracias a que en un futuro cercano entrarán en operación algunos telescopios especialmente adecuados a estos propósitos. Por tal motivo, hemos comenzado desde hace un tiempo un esfuerzo en cuanto al estudio de la evolución planetaria. A tales efectos hemos adaptado el código de evolución estelar de nuestro Observatorio al caso planetario. Las principales diferencias entre el caso estelar y el planetario se encuentran en la ecuación de estado. A tales fines hemos incluído la reciente ecuación de estado de Saumon, Chabrier y Van Horn, las opacidades radiativas de Guillot et al., procesos de quema de Deuterio, etc. También se ha considerado la posible existencia de fases de hielo y roca en el interior planetario. Por el momento hemos despreciado los efectos de la rotación planetaria. Con este código hemos computado la evolución de planetas con masas desde 10 hasta 0.3 masas de Júpiter. Utilizando nuestros resultados numéricos discutimos la detectabilidad de estos objetos en condiciones realistas.

Lesiones subcutáneas dolorosas en paciente con melanoma metastásico: un caso de paniculitis linfocítica asociado a vemurafenib.

PubMed

Benavente-Villegas, Felipe; Ferrando-Roca, Francisco; Dolz-Gaitón, Raquel; Royo-Peiró, María

2017-10-15

Vemurafenib ha probado ser una herramienta útil en el tratamiento de melanoma metastásico con mutación BRAF-V600E. Los efectos adversos incluyen artralgias, fatiga y toxicidad cutánea, siendo infrecuente la paniculitis. Presentamos el caso de una paciente de 43 años con melanoma metastásico que desarrolla lesiones subcutáneas dolorosas en miembros inferiores y superiores, asociadas a clínica sistémica después de 2 semanas de inicio de tratamiento con Vemurafenib + Cobimetinib. La histología demostró paniculitis linfocitaria septal y lobulillar. La paciente tuvo mala tolerancia al tratamiento anti diana a dosis plenas, requiriendo su ajuste, generando una corticodependencia para controlar sintomatología, y que finalmente obligó a la descontinuación de la terapia dirigida contra melanoma.  A la fecha, se han descrito 29 casos en la literatura de paniculitis asociada a vemurafenib, siendo la mayoría paniculitis neutrofílicas con adecuado control de sintomatología asociando antiinflamatorios no esteroidales y/o corticoides orales sin requerir en su mayoría modificación de la terapia contra melanoma; sin embargo hay que tener presente que pueden haber casos con mala evolución que obligan a la reducción de dosis de vemurafenib y descontinuar el tratamiento, como ha ocurrido en nuestro reporte.Vemurafenib has proven to be a useful tool in the treatment of metastatic melanoma with BRAF-V600E mutation. Adverse effects include arthralgia, fatigue, and skin toxicity; panniculitis is a rare complication. We present the case of a 43-year-old patient with metastatic melanoma who developed painful subcutaneous nodules of the lower and upper limbs and associated systemic clinical symptoms after 2 weeks of treatment with vemurafenib plus cobimetinib. Histology showed a septal and lobular lymphocytic panniculitis.The patient had poor tolerance of the full-dose treatment, requiring its adjustment. Systemic corticosteroids were required to control symptomatology

To share or not to share? Expected pros and cons of data sharing in radiological research.

PubMed

Sardanelli, Francesco; Alì, Marco; Hunink, Myriam G; Houssami, Nehmat; Sconfienza, Luca M; Di Leo, Giovanni

2018-06-01

The aims of this paper are to illustrate the trend towards data sharing, i.e. the regulated availability of the original patient-level data obtained during a study, and to discuss the expected advantages (pros) and disadvantages (cons) of data sharing in radiological research. Expected pros include the potential for verification of original results with alternative or supplementary analyses (including estimation of reproducibility), advancement of knowledge by providing new results by testing new hypotheses (not explored by the original authors) on pre-existing databases, larger scale analyses based on individual-patient data, enhanced multidisciplinary cooperation, reduced publication of false studies, improved clinical practice, and reduced cost and time for clinical research. Expected cons are outlined as the risk that the original authors could not exploit the entire potential of the data they obtained, possible failures in patients' privacy protection, technical barriers such as the lack of standard formats, and possible data misinterpretation. Finally, open issues regarding data ownership, the role of individual patients, advocacy groups and funding institutions in decision making about sharing of data and images are discussed. • Regulated availability of patient-level data of published clinical studies (data-sharing) is expected. • Expected benefits include verification/advancement of knowledge, reduced cost/time of research, clinical improvement. • Potential drawbacks include faults in patients' identity protection and data misinterpretation.

Pros and cons of vaccination against serogroup B meningococcal disease.

PubMed

Delgado Rodríguez, Miguel; Domínguez García, Ángela

2018-02-09

A vaccine has recently been approved in the EU against meningococcal serogroup B, the main cause of meningococcal disease. There is a fierce debate about the decision regarding a universal vaccination in infants older than 2 months, as recommended by the majority of scientific societies. In western Europe the only country to have included the universal vaccination is the United Kingdom, with a lower incidence of the disease than Ireland. Other countries have also adopted it, such as the Czech Republic, Cuba and certain regions of Italy. Numerous cost-effectiveness studies have been published regarding the vaccination with different assumptions, which have supported the decision not to implant the universal vaccination because it exceeds the will to pay for a health benefit. We discuss the pros and cons of the universal vaccination against meningococcal B, recommended by the Sociedad Española de Pediatría (Spanish Society of Paediatrics), which as yet has not been implemented. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Assessment of Response to Lithium Maintenance Treatment in Bipolar Disorder: A Consortium on Lithium Genetics (ConLiGen) Report

PubMed Central

Manchia, Mirko; Adli, Mazda; Akula, Nirmala; Ardau, Raffaella; Aubry, Jean-Michel; Backlund, Lena; Banzato, Claudio EM.; Baune, Bernhard T.; Bellivier, Frank; Bengesser, Susanne; Biernacka, Joanna M.; Brichant-Petitjean, Clara; Bui, Elise; Calkin, Cynthia V.; Cheng, Andrew Tai Ann; Chillotti, Caterina; Cichon, Sven; Clark, Scott; Czerski, Piotr M.; Dantas, Clarissa; Zompo, Maria Del; DePaulo, J. Raymond; Detera-Wadleigh, Sevilla D.; Etain, Bruno; Falkai, Peter; Frisén, Louise; Frye, Mark A.; Fullerton, Jan; Gard, Sébastien; Garnham, Julie; Goes, Fernando S.; Grof, Paul; Gruber, Oliver; Hashimoto, Ryota; Hauser, Joanna; Heilbronner, Urs; Hoban, Rebecca; Hou, Liping; Jamain, Stéphane; Kahn, Jean-Pierre; Kassem, Layla; Kato, Tadafumi; Kelsoe, John R.; Kittel-Schneider, Sarah; Kliwicki, Sebastian; Kuo, Po-Hsiu; Kusumi, Ichiro; Laje, Gonzalo; Lavebratt, Catharina; Leboyer, Marion; Leckband, Susan G.; López Jaramillo, Carlos A.; Maj, Mario; Malafosse, Alain; Martinsson, Lina; Masui, Takuya; Mitchell, Philip B.; Mondimore, Frank; Monteleone, Palmiero; Nallet, Audrey; Neuner, Maria; Novák, Tomás; O’Donovan, Claire; Ösby, Urban; Ozaki, Norio; Perlis, Roy H.; Pfennig, Andrea; Potash, James B.; Reich-Erkelenz, Daniela; Reif, Andreas; Reininghaus, Eva; Richardson, Sara; Rouleau, Guy A.; Rybakowski, Janusz K.; Schalling, Martin; Schofield, Peter R.; Schubert, Oliver K.; Schweizer, Barbara; Seemüller, Florian; Grigoroiu-Serbanescu, Maria; Severino, Giovanni; Seymour, Lisa R.; Slaney, Claire; Smoller, Jordan W.; Squassina, Alessio; Stamm, Thomas; Steele, Jo; Stopkova, Pavla; Tighe, Sarah K.; Tortorella, Alfonso; Turecki, Gustavo; Wray, Naomi R.; Wright, Adam; Zandi, Peter P.; Zilles, David; Bauer, Michael; Rietschel, Marcella; McMahon, Francis J.

2013-01-01

Objective The assessment of response to lithium maintenance treatment in bipolar disorder (BD) is complicated by variable length of treatment, unpredictable clinical course, and often inconsistent compliance. Prospective and retrospective methods of assessment of lithium response have been proposed in the literature. In this study we report the key phenotypic measures of the “Retrospective Criteria of Long-Term Treatment Response in Research Subjects with Bipolar Disorder” scale currently used in the Consortium on Lithium Genetics (ConLiGen) study. Materials and Methods Twenty-nine ConLiGen sites took part in a two-stage case-vignette rating procedure to examine inter-rater agreement [Kappa (κ)] and reliability [intra-class correlation coefficient (ICC)] of lithium response. Annotated first-round vignettes and rating guidelines were circulated to expert research clinicians for training purposes between the two stages. Further, we analyzed the distributional properties of the treatment response scores available for 1,308 patients using mixture modeling. Results Substantial and moderate agreement was shown across sites in the first and second sets of vignettes (κ = 0.66 and κ = 0.54, respectively), without significant improvement from training. However, definition of response using the A score as a quantitative trait and selecting cases with B criteria of 4 or less showed an improvement between the two stages (ICC1 = 0.71 and ICC2 = 0.75, respectively). Mixture modeling of score distribution indicated three subpopulations (full responders, partial responders, non responders). Conclusions We identified two definitions of lithium response, one dichotomous and the other continuous, with moderate to substantial inter-rater agreement and reliability. Accurate phenotypic measurement of lithium response is crucial for the ongoing ConLiGen pharmacogenomic study. PMID:23840348

Nationwide trends in the current management of desmoid (aggressive) fibromatosis.

PubMed

Eastley, N C; Hennig, I M; Esler, C P; Ashford, R U

2015-06-01

The optimal management of desmoid fibromatosis remains unclear, leading to significant variability in patient management. To assess this problem, the current approach of clinicians managing this complex condition in the UK was investigated. A hypothetical case of intramuscular limb girdle desmoid fibromatosis in a fit 65-year-old patient was devised. Surgical and non-surgical oncology members of the British Sarcoma Group were questioned on how they would manage this case in three scenarios: primary disease with function-sparing surgery possible, primary disease with neurovascular involvement and disease recurrence after a previous R0 resection. Initial management, management of symptomatic disease progression, follow-up preferences and any differences in respondents' management choices in a younger case were investigated. The responses from 14 sarcoma surgeons and 23 oncologists (14 clinical, nine medical) were analysed. Desmoid fibromatosis management is generally shared by surgeons and oncologists within sarcoma multidisciplinary teams in the UK. Variation exists in the chosen initial management of primary desmoid fibromatosis in the UK, with function-sparing surgery possible (observation 51%, resection 51%), primary desmoid fibromatosis with neurovascular involvement (hormone therapy with non-steroidal anti-inflammatory drugs 51%, radiotherapy 27%, observation 22%) and for cases of desmoid fibromatosis recurrence (radiotherapy 41%, hormone therapy and non-steroidal anti-inflammatory drugs 27%, observation 24%). There was a clear preference of surgical resection of symptomatic disease progression in cases of primary desmoid fibromatosis without neurovascular involvement (60%). By contrast, radiotherapy was the preferred treatment for progression in cases with neurovascular involvement (47%) or cases of recurrence after a previous R0 resection (34%). Clinical follow-up was selected 3 months after intervention in 68% of scenarios. Follow-up imaging was selected 3

Recovery of Baseline Erectile Function in Men Following Radical Prostatectomy for High-Risk Prostate Cancer: A Prospective Analysis Using Validated Measures.

PubMed

Sridhar, Ashwin N; Cathcart, Paul J; Yap, Tet; Hines, John; Nathan, Senthil; Briggs, Timothy P; Kelly, John D; Minhas, Suks

2016-03-01

Recovery of baseline erectile function (EF) after robotic radical prostatectomy in men with high-risk prostate cancer is under-reported. Published studies have selectively reported on low-risk disease using non-validated and poorly defined thresholds for EF recovery. To assess return to baseline EF in men after robotic radical prostatectomy for high-risk prostate cancer. Five hundred thirty-one men underwent robotic radical prostatectomy for high-risk prostate cancer from February 2010 through July 2014. Pre- and postoperative EF was prospectively assessed using the International Index of Erectile Dysfunction (IIEF-5) questionnaire. Multivariate logistic regression analysis determined the effect of age, preoperative function, comorbidities, body mass index, prostate-specific antigen level, cancer stage or grade, nerve-sparing status, adjuvant therapy, and continence on EF return (defined as postoperative return to baseline EF with or without use of phosphodiesterase type 5 inhibitors). Kaplan-Meier analysis and log-rank test were used to analyze return over time. Mann-Whitney U-test was used to compare IIEF-5 scores. Pre- and postoperative EF was assessed using the IIEF-5 Sexual Health Inventory for Men at 3 months, 6 months, 1 year, 2 years, 3 years, and 4 years postoperatively. Overall, return of EF was seen in 23.5% of patients at 18 months. This was significantly increased in men no older than 60 years (P = .024), with a preoperative IIEF-5 score of at least 22 (P = .042), and after undergoing neurovascular bundle preservation (34.9% of patients, P < .001). There was no significant change in IIEF-5 scores from 3 to 36 months in patients who were treated with phosphodiesterase type 5 inhibitors in the non-neurovascular bundle preservation group (P = .87), although there was significant improvement in those receiving second- or third-line therapies (P = .042). Other than preoperative hypertension (P = .03), none of the other comorbidities predicted return of

Actitudes Éticas de los estudiantes y egresados en carrera de medicina con metodologías activas

PubMed Central

Novaes, Maria Rita Carvalho Garbi; Novaes, Luiz Carlos Garcez; Guilhem, Dirce; Stepke, Fernando Lolas; Silveira, Carla Cristina Costa; Komatsu, Ricardo Shoiti; Trindade, Eliane Mendonça Vilar; Guiotti, Murilo Galvão

2010-01-01

El presente estudio tiene por objeto desarrollar un diagnostico de la inserción integrada de la ética en la carrera de medicina brasileña con una metodología de aprendizaje basada en problemas y describir las percepciones de actitudes éticas de los estudiantes y egresados. El diseño metodológico es un estudio de caso, descriptivo y documental, con abordaje cualitativo y cuantitativo. La muestra de esta investigación ha sido constituida por 120 estudiantes y 40 egresados de dos promociones del Curso de Medicina de la ESCS. Este proyecto fue aprobado por el Comité de Ética en Investigación - SES/DF. Los estudiantes y egresados de la ESCS demostraron un buen manejo en el abordaje de los conflictos éticos y respeto a los pacientes. Sin embargo, el análisis de sensibilidad ética mostró una fragilidad en las percepciones y aptitudes inapropiadas de los estudiantes de la carrera de medicina, identificada básicamente en los años iniciales, que necesitan más discusiones sistematizadas sobre los aspectos éticos y bioéticos integrados a las actividades prácticas para estimular y fortalecer la reflexión ética de los estudiantes. PMID:20981242

Presentación del estudio “Links” de hombres que tienes sexo con hombres en Buenos Aires, Argentina

PubMed Central

Carballo-Diéguez, Alex; Ávila, María M; Balán, Iván C.; Marone, Rubén; Pando, María A.; Barreda, Victoria

2011-01-01

Resumen Estudios previos en Buenos Aires reportaron altas prevalencias de HIV entre HSH, con valores que oscilan entre 9 y 14% durante casi 10 años de continuo testeo. El objetivo principal de este estudio fue la evaluación de factores relacionados al comportamiento de alto riesgo para transmisión del HIV entre HSH entre los que se incluyen el conocimiento y factores emocionales, socioculturales y ambientales. Por otro lado se realizó la estimación de prevalencia e incidencia de HIV utilizando RDS (Respondent Driven Sampling), así como la presencia de otras infecciones de transmisión sexual. Por último se evaluaron los hábitos de testeo para HIV indagando que factores facilitan o impiden su realización. El estudio constó de dos fases, en primer lugar una fase cualitativa y posteriormente una fase cuantitativa con una duración total de 4 años y medio. Durante la fase cualitativa se realizaron 44 entrevistas individuales en profundidad, 8 grupos focales y 10 observaciones etnográficas (hoteles, baños públicos (“teteras”), cines pornográficos, fiestas privadas, dark rooms y discotecas). Durante la fase cuantitativa del estudio se realizó el reclutamiento de 500 participantes que provinieron de la Ciudad Autónoma de Buenos Aires, así como del Gran Buenos Aires. El reclutamiento se comenzó con 16 participantes llamados semillas. Se realizó el diagnóstico de infección por HIV, hepatitis B y C (HBV y HCV), Treponema pallidum, Virus Papiloma Humano (HPV) y Chlamidias. La colaboración establecida entre los grupos de trabajo enfocados en áreas diversas posibilitó el abordaje conjunto de nuevas estrategias de investigación antes no exploradas en nuestro país. Los resultados más relevantes de esta investigación serán progresivamente publicados en sucesivos números de Actualizaciones en SIDA. PMID:25264397

78 FR 65346 - Center for Scientific Review; Amended Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-31

... DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health Center for Scientific Review; Amended Notice of Meeting Notice is hereby given of a change in the meeting of the Brain Injury and Neurovascular Pathologies Study Section, October 10, 2013, 08:00 a.m. to October 11, 2013, 05:00 p.m., Hotel...

Neurovascular Modeling: Small-Batch Manufacturing of Silicone Vascular Replicas

PubMed Central

Chueh, J.Y.; Wakhloo, A.K.; Gounis, M.J.

2009-01-01

BACKGROUND AND PURPOSE Realistic, population based cerebrovascular replicas are required for the development of neuroendovascular devices. The objective of this work was to develop an efficient methodology for manufacturing realistic cerebrovascular replicas. MATERIALS AND METHODS Brain MR angiography data from 20 patients were acquired. The centerline of the vasculature was calculated, and geometric parameters were measured to describe quantitatively the internal carotid artery (ICA) siphon. A representative model was created on the basis of the quantitative measurements. Using this virtual model, we designed a mold with core-shell structure and converted it into a physical object by fused-deposit manufacturing. Vascular replicas were created by injection molding of different silicones. Mechanical properties, including the stiffness and luminal coefficient of friction, were measured. RESULTS The average diameter, length, and curvature of the ICA siphon were 4.15 ± 0.09 mm, 22.60 ± 0.79 mm, and 0.34 ± 0.02 mm-1 (average ± standard error of the mean), respectively. From these image datasets, we created a median virtual model, which was transformed into a physical replica by an efficient batch-manufacturing process. The coefficient of friction of the luminal surface of the replica was reduced by up to 55% by using liquid silicone rubber coatings. The modulus ranged from 0.67 to 1.15 MPa compared with 0.42 MPa from human postmortem studies, depending on the material used to make the replica. CONCLUSIONS Population-representative, smooth, and true-to-scale silicone arterial replicas with uniform wall thickness were successfully built for in vitro neurointerventional device-testing by using a batch-manufacturing process. PMID:19321626

Limb neurovascular control during altered otolithic input in humans

NASA Technical Reports Server (NTRS)

Monahan, Kevin D.; Ray, Chester A.

2002-01-01

Head-down rotation (HDR), which activates the vestibulosympathetic reflex, increases leg muscle sympathetic nerve activity (MSNA) and produces calf vasoconstriction with no change in either cardiac output or arterial blood pressure. Based on animal studies, it was hypothesized that differential control of arm and leg MSNA explains why HDR does not alter arterial blood pressure. Fifteen healthy subjects were studied. Heart rate, arterial blood pressure, forearm and calf blood flow, and leg MSNA responses were measured during HDR in these subjects. Simultaneous recordings of arm and leg MSNA were obtained from five of the subjects. Forearm and calf blood flow, vascular conductances, and vascular resistances were similar before HDR, as were arm and leg MSNA. HDR elicited similar significant increases in leg (Delta 6 +/- 1 bursts min(-1); 59 +/- 16 % from baseline) and arm MSNA (Delta 5 +/- 1 bursts min(-1); 80 +/- 28 % from baseline). HDR significantly decreased calf (-19 +/- 2 %) and forearm vascular conductance (-12 +/- 2 %) and significantly increased calf (25 +/- 4 %) and forearm vascular resistance (15 +/- 2 %), with 60 % greater vasoconstriction in the calf than in the forearm. Arterial blood pressure and heart rate were not altered by HDR. These results indicate that there is no differential control of MSNA in the arm and leg during altered feedback from the otolith organs in humans, but that greater vasoconstriction occurs in the calf than in the forearm. These findings indicate that vasodilatation occurs in other vascular bed(s) to account for the lack of increase in arterial blood pressure during HDR.

Overlap corrections for emissivity calculations of H2O-CO2-CO-N2 mixtures

NASA Astrophysics Data System (ADS)

Alberti, Michael; Weber, Roman; Mancini, Marco

2018-01-01

Calculations of total gas emissivities of gas mixtures containing several radiatively active species require corrections for band overlapping. In this paper, we generate such overlap correction charts for H2O-CO2-N2, H2O-CO-N2, and CO2-CO-N2 mixtures. These charts are applicable in the 0.1-40 bar total pressure range and in the 500 K-2500 K temperature range. For H2O-CO2-N2 mixtures, differences between our charts and Hottel's graphs as well as models of Leckner and Modak are highlighted and analyzed.