Science.gov

Sample records for collateral branches preliminary

  1. Collateral branching of long-distance cortical projections in monkey.

    PubMed

    Rockland, Kathleen S

    2013-12-15

    Collateralization of individual cortical axons is well documented for rodents but less so for monkeys, where double retrograde tracer experiments have tended to find only small numbers of neurons projecting to two different injection sites. Evidence from both double label and single axon studies, however, suggests that in specific projection systems the number of neurons with collateralized axons can be 10% or greater. These include feedback projections from temporal areas (but less so those from V4 and MT/V5). Single-axon analyses show that many parietal neurons branch to multiple targets. Except for giant Meynert cells in area V1, feedforward projections from early visual areas have only a small number of neurons with branching axons. Why only some neurons collateralize, what determines branch points and projection foci, and how this impacts network organization are largely unknown. Deciphering the branching code might offer new perspectives on space-time organization at the network level.

  2. Occlusion of the left main coronary artery and collateral circulation via the conus branch.

    PubMed

    de Agustin, Jose Alberto; Nunez-Gil, Ivan Javier; del Carmen Manzano, Maria; Vivas, David; Mateos, Borja Ruiz; Carda, Rocio; Vilacosta, Isidre; Zamorano, Jose Luis; Macaya, Carlos

    2009-05-01

    We report the case of a 71-year-old-man, a smoker, admitted for unstable angina. Subsequent investigation revealed complete proximal occlusion of the left main coronary with an unusual collateral circulation. The left coronary artery was filled by a large conus branch originating from the right sinus of Valsalva. This case shows the importance of looking for atypical collateral circulation in patients with chronic occlusion of the left main coronary artery and normal left ventricular function.

  3. Nerve Growth Factor Promotes Reorganization of the Axonal Microtubule Array at Sites of Axon Collateral Branching

    PubMed Central

    Ketschek, Andrea; Jones, Steven; Spillane, Mirela; Korobova, Farida; Svitkina, Tatyana; Gallo, Gianluca

    2015-01-01

    The localized debundling of the axonal microtubule array and the entry of microtubules into axonal filopodia are two defining features of collateral branching. We report that nerve growth factor (NGF), a branch inducing signal, increases the frequency of microtubule debundling along the axon shaft of chicken embryonic sensory neurons. Sites of debundling correlate strongly with the localized targeting of microtubules into filopodia. Platinum replica electron microscopy suggests physical interactions between debundled microtubules and axonal actin filaments. However, as evidenced by depolymerization of actin filaments and inhibition of myosin II, actomyosin force generation does not promote debundling. In contrast, loss of actin filaments or inhibition of myosin II activity promotes debundling, indicating that axonal actomyosin forces suppress debundling. MAP1B is a microtubule associated protein that represses axon branching. Following treatment with NGF, microtubules penetrating filopodia during the early stages of branching exhibited lower levels of associated MAP1B. NGF increased and decreased the levels of MAP1B phosphorylated at a GSK-3β site (pMAP1B) along the axon shaft and within axonal filopodia, respectively. The levels of MAP1B and pMAP1B were not altered at sites of debundling, relative to the rest of the axon. Unlike the previously determined effects of NGF on the axonal actin cytoskeleton, the effects of NGF on microtubule debundling were not affected by inhibition of protein synthesis. Collectively, these data indicate that NGF promotes localized axonal microtubule debundling, that actomyosin forces antagonize microtubule debundling and that NGF regulates pMAP1B in axonal filopodia during the early stages of collateral branch formation. PMID:25846486

  4. Variations of the origin of collateral branches emerging from the posterior aspect of the brachial plexus

    PubMed Central

    2007-01-01

    Background The frequency of variation found in the arrangement and distribution of the branches in the brachial plexus, make this anatomical region extremely complicated. The medical concerns involved with these variations include anesthetic blocks, surgical approaches, interpreting tumor or traumatic nervous compressions having unexplained clinical symptoms (sensory loss, pain, wakefulness and paresis), and the possibility of these structures becoming compromised. The clinical importance of these variations is discussed in the light of their differential origins. Methods The anatomy of brachial plexus structures from 46 male and 11 female cadaverous specimens were studied. The 40–80 year-old specimens were obtained from the Universidad Industrial de Santander's Medical Faculty's Anatomy Department (dissection laboratory). Parametric measures were used for calculating results. Results Almost half (47.1%) of the evaluated plexuses had collateral variations. Subscapular nerves were the most varied structure, including the presence of a novel accessory nerve. Long thoracic nerve variations were present, as were the absence of C5 or C7 involvement, and late C7 union with C5–C6. Conclusion Further studies are needed to confirm the existence of these variations in a larger sample of cadaver specimens. PMID:17587464

  5. Intraocular BDNF promotes ectopic branching, alters motility and stimulates abnormal collaterals in regenerating optic fibers.

    PubMed

    Dawson, Amy J; Miotke, Jill A; Meyer, Ronald L

    2015-07-10

    A great deal of effort has been invested in using trophic factors and other bioactive molecules to promote cell survival and axonal regeneration in the adult central nervous system. Far less attention has been paid to investigating potential effects that trophic factors may have that might interfere with recovery. In the visual system, BDNF has been previously reported to prevent regeneration. To test if BDNF is inherently incompatible with regeneration, BDNF was given intraocularly during optic nerve regeneration in the adult goldfish. In vivo imaging and anatomical analysis of selectively labeled axons were used as a sensitive assay for effects on regeneration within the tectum. BDNF had no detectable inhibitory effect on the ability of axons to regenerate. Normal numbers of axons regenerated into the tectum, exhibited dynamic growth and retractions similar to controls, and were able to navigate to their correct target zone in the tectum. However, BDNF was found to have additional effects that adversely affected the quality of regeneration. It promoted premature branching at ectopic locations, diminished the growth rate of axons through the tectum, and resulted in the formation of ectopic collaterals. Thus, although BDNF has robust effects on axonal behavior, it is, nevertheless, compatible with axonal regeneration, axon navigation and the formation of terminal arbors.

  6. Coronary collaterals.

    PubMed

    Gorlin, R

    1976-01-01

    Coronary collaterals are probably enlargements of pre-existing channels which respond to local vasodilators and which function whenever pressure differences exist across them. Thus, in human coronary atherosclerosis collaterals are only seen when there is a severe intervening arterial obstruction (in excess of 75%). Coronary collaterals follow epicardial and intramycardial pathways, and the intermediary connections may be at vessels of highly varying caliber. The flow potential of most collateral pathways in man is possibly adequate for segmental myocardial function at lower than normal demands but clearly is inadequate for most, if not all, stressful interventions. In the last analysis, coronary collaterals in man are more an indication of severe regional ischemia (present or potential) than a sign of biological "compensation'' for a perfusion deficit.

  7. Press releases, preliminary maps, and preliminary reports released by the Geologic Branch and Alaskan Branch between January 1, 1938 and January 1, 1945

    USGS Publications Warehouse

    Kent, Lois S.; Keroher, R.P.

    1945-01-01

    This pamphlet contains a complete list of all maps and reports issued by the Geologic Branch and Alaskan Branch of the Geological Survey whose release was announced by press notice during the period between January 1, 1938 and January 1, 1945. The Geologic Branch material was compiled by Lois S. Kent, and the Alaskan Branch material by R. P. Kerocher. It is expected that similar lists will be published annually hereafter. These reports and maps are the results of work carried out by Survey geologists on mineral deposits in the United States, Alaska, and Cuba during the war and the years immediately preceding the war. They were released in preliminary form as rapidly as possible in this period to avoid the delays necessarily attendant upon formal publication and to make the information contained in them promptly available to property owners and mine operators concerned with the production of strategic and critical mineral commodities.

  8. A preliminary investigation of the role of auxin and cytokinin in sylleptic branching of three hybrid poplar clones exhibiting contrasting degrees of sylleptic branching.

    PubMed

    Cline, Morris G; Dong-IL, Kim

    2002-09-01

    Sylleptic branches grow out from lateral buds during the same growing season in which the buds are formed. This type of branching is present in poplar and in many tropical species. It results in the production of more branches, more leaves and expanded photosynthetic capacity and is thought to assist in increasing the overall growth and biomass of the tree at a young age. However, very little is known about the physiology of sylleptic branching in poplar, which is an extremely important source of fibre and fuel. In the present study of three hybrid poplar clones (11-11, 47-174 and 49-177) of Populus trichocarpa x P. deltoides exhibiting contrasting degrees of sylleptic branching, an analysis was carried out on parent shoot elongation and sylleptic branching, together with a preliminary comparison of the parent shoots' sensitivity to auxin (naphthaleneacetic acid) as a repressor of lateral bud outgrowth, and cytokinin (benzyladenine) as a promoter. Suggestive evidence was found for an inverse correlation between parent shoot sensitivity to auxin and the degree of sylleptic branching, as well as a partially positive correlation with respect to sensitivity to cytokinin. The present data are consistent with the hypothesis that auxin and cytokinin may play repressive and promotive roles, respectively, in the sylleptic branching of hybrid poplar.

  9. Pathophysiology of coronary collaterals.

    PubMed

    Stoller, Michael; Seiler, Christian

    2014-02-01

    While the existence of structural adaptation of coronary anastomoses is undisputed, the potential of coronary collaterals to be capable of functional adaptation has been questioned. For many years, collateral vessels were thought to be rigid tubes allowing only limited blood flow governed by the pressure gradient across them. This concept was consistent with the notion that although collaterals could provide adequate blood flow to maintain resting levels, they would be unable to increase blood flow sufficiently in situations of increased myocardial oxygen demand. However, more recent studies have demonstrated the capability of the collateral circulation to deliver sufficient blood flow even during exertion or pharmacologic stress. Moreover, it has been shown that increases in collateral flow could be attributed directly to collateral vasomotion. This review summarizes the pathophysiology of the coronary collateral circulation, ie the functional adapation of coronary collaterals to acute alterations in the coronary circulation.

  10. Pathophysiology of Coronary Collaterals#

    PubMed Central

    Stoller, Michael; Seiler, Christian

    2014-01-01

    While the existence of structural adaptation of coronary anastomoses is undisputed, the potential of coronary collaterals to be capable of functional adaptation has been questioned. For many years, collateral vessels were thought to be rigid tubes allowing only limited blood flow governed by the pressure gradient across them. This concept was consistent with the notion that although collaterals could provide adequate blood flow to maintain resting levels, they would be unable to increase blood flow sufficiently in situations of increased myocardial oxygen demand. However, more recent studies have demonstrated the capability of the collateral circulation to deliver sufficient blood flow even during exertion or pharmacologic stress. Moreover, it has been shown that increases in collateral flow could be attributed directly to collateral vasomotion. This review summarizes the pathophysiology of the coronary collateral circulation, ie the functional adapation of coronary collaterals to acute alterations in the coronary circulation. PMID:23701025

  11. Axonal degeneration, distal collateral branching and neuromuscular junction architecture alterations occur prior to symptom onset in the SOD1(G93A) mouse model of amyotrophic lateral sclerosis.

    PubMed

    Clark, Jayden A; Southam, Katherine A; Blizzard, Catherine A; King, Anna E; Dickson, Tracey C

    2016-10-01

    Degeneration of the distal axon and neuromuscular junction (NMJ) is considered a key and early feature of the pathology that accompanies motor neuron loss in people with amyotrophic lateral sclerosis (ALS). The mutant SOD1(G93A) mouse replicates many features of the disease, however the sequence of events resulting in degeneration of the neuromuscular circuitry remains unknown. Furthermore, despite widespread degenerative neuronal pathology throughout the spinal cord in this model, hindlimb motor function is lost before forelimb function. We investigated axons and NMJs in the hindlimb (gastrocnemius) and forelimb (extensor) muscles in the high copy number mutant SOD1(G93A)xYFP (yellow fluorescent protein) mouse. We found that distal axonal and NMJ alterations were present prior to previously reported functional symptom onset in this strain. Indeed, increased branch complexity as well as colocalisation between pre- and post-synaptic markers indicated widespread early axonal and NMJ alterations in the hindlimb. Immunohistochemical analysis demonstrated that the colocalisation of the scaffolding proteins nestin, LRP-4, dystrophin and rapsyn were diminished before post-synaptic receptors in the gastrocnemius, and the degree of loss differed between proteins. Analysis of the forelimb muscle revealed axonal and NMJ degeneration at a late, post symptomatic stage, as well as novel differences in NMJ morphology, with reduced complexity. Furthermore, post-synaptic scaffolding proteins were preserved in the forelimb compared with the hindlimb. Analysis of protein levels indicated an increase in LRP-4, dystrophin and rapsyn in post symptomatic skeletal muscle that may suggest ongoing attempts at repair. This study indicates that axonal and NMJ degeneration in the SOD1 model of ALS is a complex and evolving sequence of events. We provide evidence that YFP can detect morphological and plastic alterations in the SOD1(G93A) mouse, and that the pre- and post-synaptic integrity of

  12. Medial Collateral Ligament (MCL) Injuries

    MedlinePlus

    ... of Healthy Breakfasts Shyness Medial Collateral Ligament (MCL) Injuries KidsHealth > For Teens > Medial Collateral Ligament (MCL) Injuries ... Treatment Coping With an MCL Injury About MCL Injuries A torn medial collateral ligament (MCL) is a ...

  13. Channel erosion and sediment transport in Pheasant Branch basin near Middleton, Wisconsin; a preliminary report

    USGS Publications Warehouse

    Grant, R. Stephen; Goddard, Gerald

    1980-01-01

    The purpose of this 5-year study is to (1) evaluate the sediment transport, streamflow characteristics, and stream-channel morphology, (2) relate the above to land-use practices; and (3) evaluate the effect that changes in land-use practices will have on Pheasant Branch basin near Middleton, Wis. This report presents findings of sediment transport, streamflow characteristics, and stream-channel morphology from the first year of the study and documents historical erosion. The study is being conducted by the U.S. Geological Survey in cooperation with the city of Middleton and the Wisconsin Geological and Natural History Survey. Pheasant Branch, a tributary to Lake Mendota, drains 23.1 square miles of glacial drift. Channel erosion is severe within Middleton, requiring extensive use of erosion-control structures. Occasionally, channel dredging near the mouth and into Lake Mendota is required for boating. Comparison of stream-channel surveys of 1971 and 1977 shows the lowest part of the channel lowered 3 to 4 feet at some sites in the urban reach from U.S. Highway 12 downstream to Century Avenue. Downstream from Century Avenue, channel width increased from about 35 to 48 feet and channel cross-section area increased about 86 percent. A survey of Pheasant Branch in 1971 provided data for quantification of stream-channel changes since that time. Six erosion-control structures previously installed appear to have had some benefit in controlling head cutting in the channel. (USGS).

  14. Ulnar Collateral Ligament Reconstruction

    PubMed Central

    Erickson, Brandon J.; Harris, Joshua D.; Chalmers, Peter N.; Bach, Bernard R.; Verma, Nikhil N.; Bush-Joseph, Charles A.; Romeo, Anthony A.

    2015-01-01

    Context: Ulnar collateral ligament (UCL) injuries lead to pain and loss of performance in the thrower’s elbow. Ulnar collateral ligament reconstruction (UCLR) is a reliable treatment option for the symptomatic, deficient UCL. Injury to the UCL usually occurs because of chronic accumulation of microtrauma, although acute ruptures occur and an acute-on-chronic presentation is also common. Evidence Acquisition: Computerized databases, references from pertinent articles, and research institutions were searched for all studies using the search terms ulnar collateral ligament from 1970 until 2015. Study Design: Clinical review. Level of Evidence: Level 5. Results: All studies reporting outcomes for UCLR are level 4. Most modern fixation methodologies appear to be biomechanically and clinically equivalent. Viable graft choices include ipsilateral palmaris longus tendon autograft, gracilis or semitendinosus autograft, and allograft. Clinical studies report excellent outcomes of UCLR for both recreational and elite level athletes with regard to return to sport and postoperative performance. Complications, although rare, include graft rerupture or attenuation, ulnar nerve symptoms, stiffness, pain, and/or weakness leading to decreased performance. Conclusion: Injuries to the UCL have become commonplace among pitchers. Nonoperative treatment should be attempted, but the limited studies have not shown promising results. Operative treatment can be performed with several techniques, with retrospective studies showing promising results. Complications include ulnar neuropathy as well as failure to return to sport. Detailed preoperative planning, meticulous surgical technique, and a comprehensive rehabilitation program are essential components to achieving a satisfactory result. PMID:26502444

  15. [Thinking of literature studies of collaterals].

    PubMed

    Li, Jie; Liang, Fan-Rong; Li, Ying

    2006-12-01

    Summarize recent 20 years' achievements in studying literature of channels and collaterals, analyze the problems in literature studies of collaterals and comment on literature studies of collaterals, and hold that systematical summarization and study of traditional theories of collaterals can explore collateral theory and its clinical application value, and summarization of literature should refine and raise theoretical structure and scientific connotation of the collateral theory, and serve for modern studies of collaterals and collateral diseases on the basis of systematical summarization and studies of traditional literature of collaterals.

  16. Branch enclosure BVOC flux measurements from Fagus sylvatica L. in a natural forest environment: preliminary results

    NASA Astrophysics Data System (ADS)

    Demarcke, M.; Amelynck, C.; Schoon, N.; Müller, J.-F.; Joo, E.; Dewulf, J.; van Langenhove, H.; Šimpraga, M.; Steppe, K.; Lemeur, R.; Samson, R.

    2009-04-01

    Natural ecosystems, such as forests, are known to be important sources of non-methane volatile organic compounds (NMVOCs). Oxidation of these biogenic VOCs (BVOCs) in the presence of nitrogen oxides can result in net ozone formation and the low-volatility oxidation products may contribute to secondary organic aerosol formation and/or growth. As a result BVOC emissions can have a negative effect on air quality and human health. In the commonly used emission algorithms [Guenther et al., 1995], leaf temperature and photosynthetic photon flux density (PPFD) are the driving variables for BVOC emissions. However, in order to better explain the variability over time of BVOC emissions for a given tree species, the most recent emission algorithms, such as MEGAN [Guenther et al., 2006], also consider other driving variables such as phenology, temperature and light history. To validate these new emission algorithms, dynamic branch enclosure BVOC flux measurements have been performed on an adult Fagus sylvatica L. tree in a natural forest environment under ambient PPFD and temperature conditions. Branches at different levels in the canopy were accessible from a 35 m high measurement tower. The cuvette air was analysed on-line with a hs-PTR-MS instrument, which was located in a log cabin at the bottom of the tower. Ion signals related to monoterpenoid compounds (m/z 81 and 137), isoprene (m/z 69), acetone (m/z 59) and methanol (m/z 33) have been measured continuously with the PTR-MS during several phenological periods, from bud-break to senescence. The data show high monoterpenoid emission rates in spring which gradually decrease until leaf fall. Furthermore, monoterpenoid emissions from shaded leaves in the lower layers of the canopy were found to be negligible compared to those from sunlit leaves in the upper layer of the canopy. Effects of light and temperature history on monoterpenoid emissions from Fagus sylvatica L. will be discussed and compared with results obtained in

  17. Obstructive Sleep Apnea in Patients with Branch Retinal Vein Occlusion: A Preliminary Study

    PubMed Central

    Kwon, Hee Jung; Kang, Eui Chun; Lee, Junwon; Han, Jinu

    2016-01-01

    Purpose Our study aimed to determine whether obstructive sleep apnea (OSA) is common among branch retinal vein occlusion (BRVO) patients without systemic risk factors using a Watch PAT-100 portable monitoring device. Methods The study participants included consecutive patients with BRVO of less than 3 months duration without any risk factors known to be associated with OSA (diabetes, coronary artery disease, stroke, hematologic diseases, autoimmune disease, etc.) except for hypertension. All patients underwent full-night unattended polysomnography by means of a portable monitor Watch PAT-100 device. The apnea-hypopnea index (AHI) was calculated as the average number of apnea and hypopnea events per hour of sleep, and an AHI score of five or more events was diagnosed as OSA. Results Among 19 patients (6 males and 13 females), 42.1% (8 of 19) had an AHI reflective of OSA. In the 13 patients who had no concurrent illness, including hypertension, 30.8% (4 of 13) had positive test results for OSA; three of these patients were ranked as mild OSA, while one had moderate OSA. The OSA group had an average AHI of 12.3 ± 7.8, and the average AHI was 2.0 ± 0.9 in the non-OSA group. Although it was not statistically proven, we found that OSA patients experienced a more severe form of BRVO. Conclusions We found a higher than expected rate of OSA in BRVO patients lacking concomitant diseases typically associated with OSA. Our findings suggest that OSA could be an additional risk factor in the pathogenesis of BRVO or at least a frequently associated condition that could function as a triggering factor. PMID:27051260

  18. Characterization of intestinal collateral blood flow in the developing piglet.

    PubMed

    Crissinger, K D; Granger, D N

    1988-10-01

    Interest in the pathogenesis of neonatal necrotizing enterocolitis has prompted study of the intestinal circulation in developing animals. It is conceivable that poorly developed collateral channels may predispose the neonatal intestine to ischemic insults. We therefore characterized intestinal collateral blood flow in anesthetized and ventilated 1-day and 1-month-old piglets. Intestinal blood flow was measured with radioactive microspheres (15 micron diameter) before and after either 1) total occlusion of the superior mesenteric artery (SMA) or 2) occlusion of a distal (jejunoileal) branch of the SMA. After total SMA occlusion in 1-day and 1-month-old piglets, perfusion of the intestine via collaterals from the celiac and inferior mesenteric arteries was not evident. Jejunal, ileal, and colonic (except rectal) blood flows fell to zero 30 min after ligation of the SMA. Ligation of a distal branch of the SMA in 1-month-old animals significantly reduced total wall (by 25%) and mucosal/submucosal (by 25%) blood flows in the occluded segment. Similar experiments in 1-day-old piglets produced significantly greater reduction in total (70%) and mucosa/submucosa (70%) blood flows. Muscle/serosa blood flows in both groups were not significantly different from control values. In conclusion, collateral perfusion of the intestine via the celiac and inferior mesenteric arteries is insignificant during acute SMA occlusion in the developing piglet. Although there is significant collateral blood flow within the SMA vascular network, perfusion between adjacent gut segments is less effective in preventing intestinal ischemia after occlusion of a branch of the SMA in neonates than in 1-month-old piglets.

  19. Military Robotics and Collateral Damage

    DTIC Science & Technology

    2004-06-01

    Applications and Operations Military Robotics and Collateral Damage Robert Douglass (Primary POC) SET Associates 3811 N. Fairfax...2004 4. TITLE AND SUBTITLE Military Robotics and Collateral Damage 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Abstract We explore a concept of a combined force of air and ground combat robots

  20. Anatomic study of the collateral blood supply of the sternum.

    PubMed

    de Jesus, R A; Acland, R D

    1995-01-01

    A microdissection study was carried out on ten injected, cleared human sternal specimens. Three types of vessel were identified that have the potential to carry blood to the sternum after mobilization of the internal thoracic artery (ITA): (1) branches of the ITA that supply both the sternum and the pectoralis major ("sternal/perforating branches"), (2) branches of the ITA that supply both the sternum and an adjoining intercostal space ("sternal/intercostal branches"), and (3) posterior intercostal arteries that do not anastomose with an ITA branch but continue past the ITA to reach the sternum. All three types of vessel were found more frequently in the proximal than in the distal half of the sternum. For sternal/perforating and sternal/intercostal vessels to function as collaterals after ITA bypass grafting, their short common trunks of origin must remain intact. The data support the recommendation that the branches of the ITA be ligated as close as possible to the ITA itself to preserve collateral blood flow to the sternum.

  1. Nettleship collaterals: circumpapillary cilioretinal anastomoses after occlusion of the central retinal artery.

    PubMed

    Ragge, N K; Hoyt, W F

    1992-03-01

    In extremely rare cases, after occlusion of the central retinal artery, a complete ring of peripapillary anastomotic channels develops. One such case is described and a proposed term given to these channels--'Nettleship collaterals'--after the man who first described them. These collaterals are dilated pathways within the terminal capillary networks of the posterior ciliary arteries and the branches of the central retinal artery. Formation of the channels is believed to be promoted by prelaminar obstruction of the central retinal artery.

  2. Ulnar Collateral Ligament Reconstruction

    PubMed Central

    Erickson, Brandon J.; Bach, Bernard R.; Cohen, Mark S.; Bush-Joseph, Charles A.; Cole, Brian J.; Verma, Nikhil N.; Nicholson, Gregory P.; Romeo, Anthony A.

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) is a common surgery performed in professional, collegiate, and high school athletes. Purpose: To report patient demographics, surgical techniques, and outcomes of all UCLRs performed at a single institution from 2004 to 2014. Study Design: Case series; Level of evidence, 4. Methods: All patients who underwent UCLR from January 1, 2004, through December 31, 2014, at a single institution were identified. Charts were reviewed to determine patient age, sex, date of surgery, sport played, athletic level, surgical technique, graft type, and complications. Data were collected prospectively, and patients were contacted via phone calls to obtain the return-to-sport rate, Conway-Jobe score, Andrews-Timmerman score, and Kerlan-Jobe Orthopaedic Clinic (KJOC) Shoulder and Elbow score. Continuous variable data were reported as weighted means, and categorical variable data were reported as frequencies with percentages. Results: A total of 187 patients (188 elbows) underwent UCLR during the study period (92% male; mean age, 19.6 ± 4.7 years; 78.2% right elbows). There were 165 baseball players (87.8% of all patients), 155 of whom were pitchers (82.5% of all patients). Ninety-seven (51.6%) were college athletes, 68 (36.2%) high school athletes, and 7 (3.7%) professional athletes at the time of surgery. The docking technique was used in 110 (58.5%) patients while the double-docking technique was used in 78 (41.5%). An ipsilateral palmaris longus graft was used in 110 (58.5%) patients while a hamstring autograft was used in 48 (25.5%) patients. The ulnar nerve was subcutaneously transposed in 79 (42%) patients. Clinical follow-up data were available on 85 patients. Mean follow-up was 60 ± 30.8 months. Overall, 94.1% of patients were able to return to sport and had a Conway-Jobe score of good/excellent while 4.3% had a score of fair. The mean KJOC score was 90.4 ± 6.7 and mean Andrews-Timmerman score was 92.5 ± 7

  3. Coronary collateral circulation: its relevance.

    PubMed

    Karrowni, Wassef; El Accaoui, Ramzi N; Chatterjee, Kanu

    2013-11-15

    The interest in coronary collateral circulation (CCC) as "natural bypasses" is growing, especially in patients in whom the extent of coronary atherosclerosis is too severe to allow for conventional revascularization. The anatomic foundation of CCC has been recognized for long time. Recently, reliable methods have become available for the assessment of the adequacy of collateral flow. However, the debate regarding the importance of CCC in the different clinical settings continues. In this article, we present the recent progress in the understanding of anatomy and physiology of the CCC and focus on the studies addressing their functional significance in acute, subacute, and chronic coronary artery disease. In addition, we provide a focused update on the essential role of collateral circulation in the management of coronary chronic total occlusions.

  4. Systematic and differential myelination of axon collaterals in the mammalian auditory brainstem

    PubMed Central

    Seidl, Armin H.; Rubel, Edwin W

    2015-01-01

    A brainstem circuit for encoding the spatial location of sounds involves neurons in the cochlear nucleus that project to medial superior olivary (MSO) neurons on both sides of the brain via a single bifurcating axon. Neurons in MSO act as coincidence detectors, responding optimally when signals from the two ears arrive within a few microseconds. To achieve this, transmission of signals along the contralateral collateral must be faster than transmission of the same signals along the ipsilateral collateral. We demonstrate that this is achieved by differential regulation of myelination and axon caliber along the ipsilateral and contralateral branches of single axons; ipsilateral axon branches have shorter internode lengths and smaller caliber than contralateral branches. The myelination difference is established prior to the onset of hearing. We conclude that this differential myelination and axon caliber requires local interactions between axon collaterals and surrounding oligodendrocytes on the two sides of the brainstem. PMID:26556176

  5. 31 CFR 202.6 - Collateral security.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 2 2013-07-01 2013-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the...

  6. 31 CFR 202.6 - Collateral security.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Collateral security. 202.6 Section... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the...

  7. 31 CFR 202.6 - Collateral security.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 2 2012-07-01 2012-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the...

  8. 31 CFR 202.6 - Collateral security.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Collateral security. 202.6 Section 202... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money, a depositary authorized to perform services under § 202.3(b) must pledge collateral security in the...

  9. Noncoronary Collateral Myocardial Blood Flow: The Human Heart’s Forgotten Blood Supply

    PubMed Central

    Picichè, Marco

    2015-01-01

    The “noncoronary collateral circulation” (NCCC) or “noncoronary collateral myocardial blood flow” (NCCMBF), reaches the heart through a micro-vascular network arising from the bronchial, esophageal, pericardial, diaphragmatic, and aortic arteries. The left and right internal thoracic arteries (ITAs) along with their collateral branches also serve as a source of NCCMBF-a feature seen in other mammals. Under certain circumstances the ITAs have a high potential for developing collateral branches. In the case of severe Leriche syndrome or with chronic obstruction of the abdominal aorta, the ITAs can serve as the main or even sole source of blood supply to the lower limbs. It is also possible for the ITAs to develop angiographically visible branches that directly connect with the coronary arteries. In ischemic conditions there is a functional, ischemia-reducing extracardiac coronary artery supply via natural ipsilateral ITA anastomosis. To date we know little about NCCMBF and its potential benefits in clinical applications, which makes this a challenging and intriguing field of research. This paper reviews all available data on noncoronary collateral blood supply to the human heart. PMID:27006713

  10. [The significance of cervical collaterals in the subclavian steal phenomenon].

    PubMed

    Yamaguchi, K; Uchiyama, S

    1993-09-01

    The subclavian steal syndrome (SSS) is often associated with occlusive disease involving the subclavian or innominate arteries, but an asymptomatic subclavian steal, called the "subclavian steal phenomenon" (SSP), is not uncommon. Though intracranial collaterals had been postulated as one of the etiologies for the SSP's being asymptomatic, little has been accomplished in the investigation of extracranial channels. To study the hemodynamic role of cervical collateral channels, an angiographical study was done in three cases with SSP. The three cases were admitted to the hospital because of carotid ischemic symptoms, such as right hemiplegia or sensory aphasia. Each case had a blood pressure difference between the two arms, but in all of them the past history or the exercise test was negative for vertebrobasilar or arm ischemia. On angiography, occlusions of the unilateral proximal subclavian artery, the left in case 1 and the right in case 2, or a tight stenosis of the innominate artery was found in case 3. In each case, the vertebral artery flow in the affected side was inverted, siphoning off from the opposite vertebral artery into the affected subclavian artery. In addition to the vertebral siphoning; muscular branches of ipsilateral external carotid origin in cases 1 and 2, or the thyrocervical trunk via the inferior thyroid artery in case 3 was also found to function as a collateral channel to the vertebral artery on the affected side.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Intracranial Arteries - Anatomy and Collaterals.

    PubMed

    Liebeskind, David S; Caplan, Louis R

    2016-01-01

    Anatomy, physiology, and pathophysiology are inextricably linked in patients with intracranial atherosclerosis. Knowledge of abnormal or pathological conditions such as intracranial atherosclerosis stems from detailed recognition of the normal pattern of vascular anatomy. The vascular anatomy of the intracranial arteries, both at the level of the vessel wall and as a larger structure or conduit, is a reflection of physiology over time, from in utero stages through adult life. The unique characteristics of arteries at the base of the brain may help our understanding of atherosclerotic lesions that tend to afflict specific arterial segments. Although much of the knowledge regarding intracranial arteries originates from pathology and angiography series over several centuries, evolving noninvasive techniques have rapidly expanded our perspective. As each imaging modality provides a depiction that combines anatomy and flow physiology, it is important to interpret each image with a solid understanding of typical arterial anatomy and corresponding collateral routes. Compensatory collateral perfusion and downstream flow status have recently emerged as pivotal variables in the clinical management of patients with atherosclerosis. Ongoing studies that illustrate the anatomy and pathophysiology of these proximal arterial segments across modalities will help refine our knowledge of the interplay between vascular anatomy and cerebral blood flow. Future studies may help elucidate pivotal arterial factors far beyond the degree of stenosis, examining downstream influences on cerebral perfusion, artery-to-artery thromboembolic potential, amenability to endovascular therapies and stent conformation, and the propensity for restenosis due to biophysical factors.

  12. 7 CFR 2201.20 - Collateral.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Assets to be used in the delivery of the service for which the Loan is guaranteed. Such Assets may include, but are not limited to, the following: (1) Tangible Assets, including current Assets (such as... Collateral. Collateral required by paragraph (a) of this section shall consist solely of Assets of...

  13. 7 CFR 2201.20 - Collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Assets to be used in the delivery of the service for which the Loan is guaranteed. Such Assets may include, but are not limited to, the following: (1) Tangible Assets, including current Assets (such as... Collateral. Collateral required by paragraph (a) of this section shall consist solely of Assets of...

  14. 31 CFR 202.6 - Collateral security.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Service's web site at www.publicdebt.treas.gov. (c) Deposits of securities. Unless the Secretary of the... 31 Money and Finance: Treasury 2 2014-07-01 2014-07-01 false Collateral security. 202.6 Section... GOVERNMENT 1 § 202.6 Collateral security. (a) Requirement. Prior to receiving deposits of public money,...

  15. 28 CFR 94.25 - Collateral sources.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 28 Judicial Administration 2 2013-07-01 2013-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of...

  16. 28 CFR 94.25 - Collateral sources.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 28 Judicial Administration 2 2012-07-01 2012-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of...

  17. 28 CFR 94.25 - Collateral sources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of...

  18. 28 CFR 94.25 - Collateral sources.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 28 Judicial Administration 2 2014-07-01 2014-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of...

  19. 28 CFR 94.25 - Collateral sources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Collateral sources. 94.25 Section 94.25 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) CRIME VICTIM SERVICES International Terrorism Victim Expense Reimbursement Program Coverage § 94.25 Collateral sources. (a) The amount of...

  20. 7 CFR 2201.20 - Collateral.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Collateral. 2201.20 Section 2201.20 Agriculture Regulations of the Department of Agriculture (Continued) LOCAL TELEVISION LOAN GUARANTEE BOARD LOCAL TELEVISION LOAN GUARANTEE PROGRAM-PROGRAM REGULATIONS Loan Guarantees § 2201.20 Collateral. (a) Existence...

  1. 7 CFR 2201.20 - Collateral.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Collateral. 2201.20 Section 2201.20 Agriculture Regulations of the Department of Agriculture (Continued) LOCAL TELEVISION LOAN GUARANTEE BOARD LOCAL TELEVISION LOAN GUARANTEE PROGRAM-PROGRAM REGULATIONS Loan Guarantees § 2201.20 Collateral. (a) Existence...

  2. 12 CFR 725.19 - Collateral requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Collateral requirements. 725.19 Section 725.19 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS NATIONAL CREDIT UNION ADMINISTRATION CENTRAL LIQUIDITY FACILITY § 725.19 Collateral requirements. (a)...

  3. 45 CFR 160.532 - Collateral estoppel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Collateral estoppel. 160.532 Section 160.532 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES ADMINISTRATIVE DATA STANDARDS AND RELATED REQUIREMENTS GENERAL ADMINISTRATIVE REQUIREMENTS Procedures for Hearings § 160.532 Collateral estoppel. When...

  4. Nettleship collaterals: circumpapillary cilioretinal anastomoses after occlusion of the central retinal artery.

    PubMed Central

    Ragge, N K; Hoyt, W F

    1992-01-01

    In extremely rare cases, after occlusion of the central retinal artery, a complete ring of peripapillary anastomotic channels develops. One such case is described and a proposed term given to these channels--'Nettleship collaterals'--after the man who first described them. These collaterals are dilated pathways within the terminal capillary networks of the posterior ciliary arteries and the branches of the central retinal artery. Formation of the channels is believed to be promoted by prelaminar obstruction of the central retinal artery. Images PMID:1540571

  5. Selective cortical control of information flow through different intraspinal collaterals of the same muscle afferent fiber.

    PubMed

    Eguibar, J R; Quevedo, J; Jiménez, I; Rudomin, P

    1994-04-18

    We have analyzed in the anesthetized cat the effects of electrical stimulation of the cerebral cortex on the intraspinal threshold of two collaterals belonging to the same muscle spindle or tendon organ afferent fiber. The results obtained provide, for the first time, direct evidence showing that the motor cortex is able to modify, in a highly selective manner, the synaptic effectiveness of individual collaterals of the same primary afferent fiber. This presynaptic control could function as a mechanism that allows funneling of information to specific groups of spinal neurons in the presence of extensive intraspinal branching of the afferent fibers.

  6. [Simple analysis on collateral therapy in Huangdi's Internal Classic].

    PubMed

    Li, Jie; Liang, Fan-rong; Xia, Xiao-hong; Zhao, Zheng-yu

    2005-12-01

    Collateral therapy includes treatment of diseases of collaterals, and treatment of human other diseases with collaterals as treating subjects. In collateral therapy of Huangdi's Internal Classic, collaterals were used as treating subjects, and the treatment was directly given at the collaterals of lesion; for treatment methods, acupuncture and moxibustion were adopted as main method, including pricking blood therapy, moxibustion of collaterals, acupuncture; the diseases and syndromes of treatment included diseases and syndromes of channels and collaterals, and human other diseases and syndromes; the principles of reinforcing and reducing, and the principles of treatment varying from time to time were stressed, and it indicated contraindications for treatment.

  7. Intraoperative neuromonitoring of the external branch of the superior laryngeal nerve during robotic thyroid surgery: a preliminary prospective study

    PubMed Central

    Kim, Su-jin; Oh, Byung-Mo; Oh, Eun Mee; Bae, Dong Sik; Choi, June Young; Myong, Jun Pyo; Youn, Yeo-Kyu

    2015-01-01

    Purpose The aim of this study was to evaluate the feasibility of monitoring external branch of the superior laryngeal nerve (EBSLN) during robotic thyroid surgery. Methods A total of 10 patients undergoing bilateral axillo-breast approach (BABA) robotic thyroid surgery were enrolled. The nerve integrity monitor (NIM Response 2.0 System) was used for EBSLN monitoring. We performed voice assessments preoperatively and at 1 and 3 months postoperatively using Voice Handicap Index-10 (VHI-10), maximal phonation time (MPT), phonation efficient index (PEI), and laryngeal electromyography (EMG). Results A total of 19 EBSLNs were at risk and 14 EBSLNs (73.7%) were identified using neuromonitoring. VHI-10 showed a change of voice over time (0.1 vs. 3.6 vs. 1.3); however, this was not statistically significant. VHI-10 scores normalized at 3 months postoperatively compared to the preoperative scores. MPT (a) (16.0 vs. 15.6 vs. 15.4), and MPT (e) (20.1 vs. 15.4 vs. 18.5) showed no significant differences preoperatively compared to the values obtained 1 and 3 months postoperatively. There was a significant change of PEI over time (4.8 vs. 1.1 vs. 4.6) (P = 0.036); however, the values normalized at 3 months postoperatively. Laryngeal EMG results showed 4 cases (21.2%) of neuropathy of EBSLNs at 1 month postoperatively, and electrodiagnostic studies revealed nearly complete recovery of the function of EBSLNs in 4 patients at 3 months postoperatively Conclusion It is suggested that neuromonitoring of EBSLNs during BABA robotic thyroid surgery is feasible and might be helpful to preserve voice quality. PMID:26576402

  8. The Effect of Placing Flow-Diverting Stents in Intracranial Collateral Arteries of Miniature Pig

    PubMed Central

    Wang, Jiwei; Ding, Yanan; Wang, Qiuxia; Wang, Yanan; Mu, Shiqing; Bi, Lixin; Li, Youxiang

    2017-01-01

    Background Flow-diverting stent (FDS) has been suggested as an effective intracranial aneurysm treatment. However, the effects of FDS on collateral branches of an aneurysm parent artery still remain unknown. Thus, the present study aimed to comprehensively evaluate the effects of placing a FDS in the intracranial collateral artery, using a miniature pig animal model. Material/Methods Ten healthy miniature pigs were included in the study: one pig was reserved as a control and the remaining nine pigs were placed in three experimental groups: FDS (i.e., Pipeline), LVIS, and Solitaier-AB stent groups. Pigs in the experimental groups were examined by cerebral angiography immediately after stent placement, followed by hemodynamic analyses. In addition, magnetic resonance imaging (MRI) of the brain of pigs in the experimental groups was performed to inspect the brain for obstruction and blood flow. Stents were examined for the growth of neointimas. Results The results showed that neointimas, consisting of smooth muscle cells, collagenous fibers, and macrophages, were 0.67 mm thick on average and partially covered the stent wires. The thickness of neointimas in the FDS group was significantly higher than in the two conventional intracranial stent groups. There was no obvious obstruction identified in collateral arteries where the FDS was placed. Conclusions These results indicated that neointimas in collateral arteries of a miniature pig would be slightly thickened after one month of FDS placement; and FDS was shown to be safe for collateral arteries. PMID:28333907

  9. 12 CFR 950.10 - Collateral valuation; appraisals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Collateral valuation; appraisals. 950.10...-BALANCE SHEET ITEMS ADVANCES Advances to Members § 950.10 Collateral valuation; appraisals. (a) Collateral...) Appraisals. A Bank may require a member to obtain an appraisal of any item of collateral, and to perform...

  10. 12 CFR 615.5335 - Bank net collateral ratio.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Bank net collateral ratio. 615.5335 Section 615... collateral ratio. (a) Each bank shall achieve and at all times maintain a net collateral ratio of at least 103 percent. (b) At a minimum, a bank shall compute its net collateral ratio as of the end of...

  11. 12 CFR 615.5335 - Bank net collateral ratio.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Bank net collateral ratio. 615.5335 Section 615... collateral ratio. (a) Each bank shall achieve and at all times maintain a net collateral ratio of at least 103 percent. (b) At a minimum, a bank shall compute its net collateral ratio as of the end of...

  12. 12 CFR 615.5335 - Bank net collateral ratio.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Bank net collateral ratio. 615.5335 Section 615... collateral ratio. (a) Each bank shall achieve and at all times maintain a net collateral ratio of at least 103 percent. (b) At a minimum, a bank shall compute its net collateral ratio as of the end of...

  13. 12 CFR 615.5335 - Bank net collateral ratio.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Bank net collateral ratio. 615.5335 Section 615... collateral ratio. (a) Each bank shall achieve and at all times maintain a net collateral ratio of at least 103 percent. (b) At a minimum, a bank shall compute its net collateral ratio as of the end of...

  14. 12 CFR 615.5335 - Bank net collateral ratio.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Bank net collateral ratio. 615.5335 Section 615... collateral ratio. (a) Each bank shall achieve and at all times maintain a net collateral ratio of at least 103 percent. (b) At a minimum, a bank shall compute its net collateral ratio as of the end of...

  15. 7 CFR 1779.48 - Collateral.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... (CONTINUED) WATER AND WASTE DISPOSAL PROGRAMS GUARANTEED LOANS § 1779.48 Collateral. (a) Lender... and ability of project management, soundness of the project, and the borrower's prospective earnings..., water rights, buildings, machinery, equipment, accounts receivable, contracts, cash, or other...

  16. Aortopulmonary collateral flow in cystic fibrosis assessed with phase-contrast MRI

    PubMed Central

    McPhail, Gary; VanDyke, Rhonda; Knowlton, Joshua; Radhakrishnan, Rupa; Clancy, John; Amin, Raouf

    2013-01-01

    Background Cystic fibrosis (CF) is a common genetic disease in Caucasians. Chronic pulmonary disease and progressive destruction of the pulmonary parenchyma are one of the major morbidities, but the relationship between clinical severity of CF and aortopulmonary collateral blood flow has not been assessed. Objective The purpose of this study is to measure changes in aortopulmonary collateral blood flow by phase-contrast magnetic resonance imaging (MRI) in children with CF across the spectrum of disease severity as measured by the forced expiratory volume in one second as percent predicted value (FEV1%). Materials and methods Sixteen patients with CF were prospectively evaluated. Eight were classified as having mild CF lung disease (FEV1 ≥80% predicted) and eight were classified as having moderate to severe CF lung disease (FEV1 <80% predicted). Seventeen age and gender matched non-CF subjects without cardiac or lung disease served as controls. Phase-contrast flow was measured at the ascending aorta, main pulmonary artery and both pulmonary arteries. Aortopulmonary collateral blood flow was calculated for each subject. The relationship between collateral flow and FEV1%P was modeled using nonparametric regression. Group differences were assessed by analysis of variance. Results Aortopulmonary collateral blood flow began to increase as FEV1%P in subjects with CF fell below 101.5% with significant further increase in the aortopulmonary collateral blood flow in the subjects with CF with moderate to severe lung disease compared to controls (0.89 vs. 0.20 L/min, (P<0.0001). Aortopulmonary collateral blood flow correlated negatively with FEV1%P (r, 0.70, P=0.0050) confirming its relationship to this established marker of disease severity. There was no statistically significant difference in results obtained from two independent observers. Conclusion These preliminary findings suggest that phase-contrast MRI can be performed reliably with consistent results and without

  17. The morphology of hair follicle afferent fibre collaterals in the spinal cord of the cat.

    PubMed

    Brown, A G; Rose, P K; Snow, P J

    1977-11-01

    1. The enzyme horseradish peroxidase (HRP) was injected into single axons that innervated hair follicle receptors to study the morphology of their collaterals in the dorsal horn of the cord. The axons were impaled near the dorsal root entrance zone in the lumbosacral spinal cord of anaesthetized cats and HRP injected by passing current through the intra-axonal micro-electrode. The morphology was revealed by subsequent histochemistry.2. Thirteen hair-follicle afferent fibres were stained including six that innervated tylotrichs (type T hair follicle afferent units) and one that innervated guard hairs (type G unit). The remaining six axons were not classified according to hair type, but, on the basis of their axonal conduction velocities, would have been either type G or T.3. Eleven axons could be traced back into the dorsal roots. Eight of these, upon entering the cord, turned and ran towards the brain. They did not divide into rostral and caudal branches. Three of the eleven did divide and gave rise to both rostral and caudal branches.4. Sixty-three collaterals were given off the thirteen stained axons. All well-filled collaterals had a strikingly similar morphology. They descended through laminae I-III of the dorsal horn into the deeper parts of lamina IV or into lamina V, before turning and ascending back into superficial lamina IV and lamina III where they branched profusely to give rise to their terminal arborizations. Terminal boutons, most commonly of the ;en passant' type, were numerous in lamina III, but were also seen in the dorsal part of lamina IV and in ventral lamina II. None were observed in dorsal lamina II or near the junction of the grey and white matter (lamina I) or in lamina V.5. The terminal arborizations of collaterals from a single hair follicle afferent fibre were in line with one another in the longitudinal axis of the cord. In the better-stained preparations the terminal arborizations of adjacent collaterals from a single axon formed a

  18. Collateral vessel physiology and functional impact-in vivo assessment of collateral channels.

    PubMed

    Lim, M; Ziaee, A; Kern, Morten J

    2004-11-01

    The existence and recruitment of collateral vessels within the coronary circulation may account for the tremendous variability in presentation, symptoms and outcome in patients with coronary atherosclerosis. Multiple episodes of ischemia have been found to produce the stimuli necessary for the growth of new vessels which result in collateral blood flow. Furthermore, there is also a subset of patients with readily recruitable collateral vessels that function to limit myocardial necrosis during an acute ischemic event. Promising early studies have utilized angiogenic growth factors as a means to stimulate collateral growth, bringing a renewal interest in their assessment and significance. We review, in brief, the significance and understanding of the development of coronary collaterals as well as the available means to assess them.

  19. Mechanical buckling of arterioles in collateral development.

    PubMed

    Liu, Qin; Han, Hai-Chao

    2013-01-07

    Collateral arterioles enlarge in both diameter and length, and develop corkscrew-like tortuous patterns during remodeling. Recent studies showed that artery buckling could lead to tortuosity. The objective of this study was to determine arteriole critical buckling pressure and buckling pattern during arteriole remodeling. Arterioles were modeled as elastic cylindrical vessels with an elastic matrix support and underwent axial and radial growth. Our results demonstrated that arteriole critical buckling pressure decreased with increasing axial growth ratio and radius growth ratio, but increased with increasing wall thickness. Arteriole buckling mode number increased (wavelength decreased) with increasing axial growth ratio, but decreased with increasing radius growth ratio and wall thickness. Our study suggests that axial growth in arterioles makes them prone to buckling and that buckling leads to tortuous collaterals. These results shed light on the mechanism of collateral arteriole tortuosity.

  20. Mechanical Buckling of Arterioles in Collateral Development

    PubMed Central

    Liu, Qin; Han, Hai-Chao

    2012-01-01

    Collateral arterioles enlarge in both diameter and length, and develop corkscrew-like tortuous patterns during remodeling. Recent studies showed that artery buckling could lead to tortuosity. The objective of this study was to determine arteriole critical buckling pressure and buckling pattern during arteriole remodeling. Arterioles were modeled as elastic cylindrical vessels with an elastic matrix support and underwent axial and radial growth. Our results demonstrated that arteriole critical buckling pressure decreased with increasing axial growth ratio and radius growth ratio, but increased with increasing wall thickness. Arteriole buckling mode number increased (wave length decreased) with increasing axial growth ratio, but decreased with increasing radius growth ratio and wall thickness. Our study suggests that axial growth in arterioles makes them prone to buckling and that buckling leads to tortuous collaterals. These results shed light on the mechanism of collateral arteriole tortuosity. PMID:23034307

  1. Impact of Slow Blood Filling via Collaterals on Infarct Growth: Comparison of Mismatch and Collateral Status

    PubMed Central

    Son, Jeong Pyo; Lee, Mi Ji; Kim, Suk Jae; Chung, Jong-Won; Cha, Jihoon; Kim, Gyeong-Moon; Chung, Chin-Sang; Lee, Kwang Ho; Bang, Oh Young

    2017-01-01

    Background and Purpose Perfusion-diffusion mismatch has been evaluated to determine whether the presence of a target mismatch helps to identify patients who respond favorably to recanalization therapies. We compared the impact on infarct growth of collateral status and the presence of a penumbra, using magnetic resonance perfusion (MRP) techniques. Methods Consecutive patients who were candidates for recanalization therapy and underwent serial diffusion-weighted imaging (DWI) and MRP were enrolled. A collateral flow map derived from MRP source data was generated by automatic post-processing. The impact of a target mismatch (Tmax>6 s/apparent diffusion coefficient (ADC) volume≥1.8, ADC volume<70 mL; and Tmax>10 s for ADC volume<100 mL) on infarct growth was compared with MR-based collateral grading on day 7 DWI, using multivariate linear regression analysis. Results Among 73 patients, 55 (75%) showed a target mismatch, whereas collaterals were poor in 14 (19.2%), intermediate in 36 (49.3%), and good in 23 (31.5%) patients. After adjusting for initial severity of stroke, early recanalization (P<0.001) and the MR-based collateral grading (P=0.001), but not the presence of a target mismatch, were independently associated with infarct growth. Even in patients with a target mismatch and successful recanalization, the degree of infarct growth depended on the collateral status. Perfusion status at later Tmax time points (beyond the arterial phase) was more closely correlated with collateral status. Conclusions Patients with good collaterals show a favorable outcome in terms of infarct growth, regardless of the presence of a target mismatch pattern. The presence of slow blood filling predicts collateral status and infarct growth. PMID:28030891

  2. Hybrid Coronary Artery Revascularization for Takayasu Arteritis with Major Visceral Collateral Circulation from the Left Internal Thoracic Artery

    PubMed Central

    Sim, Hyung Tae; Kim, Jeong-Won; Yoo, Jae Suk; Cho, Kwang Ree

    2017-01-01

    Coronary arterial involvement in Takayasu arteritis (TA) is not uncommon. Herein, we describe a case of TA with celiac trunk and superior mesenteric artery occlusion combined with coronary artery disease. Bilateral huge internal thoracic arteries (ITAs) and the inferior mesenteric artery provided the major visceral collateral circulation. After percutaneous intervention to the right coronary artery, off-pump coronary artery bypass grafting for the left coronary territory was done using a right ITA graft and its large side branch because of its relatively minor contribution to the visceral collateral circulation. PMID:28382269

  3. 75 FR 64710 - Public Roundtable on Individual Customer Collateral Protection

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... collateral protection in the context of the CFTC's rulemaking efforts pursuant to the Dodd-Frank Wall Street... addressed at the discussion, or on any other topics related to customer collateral protection in the...

  4. Axonal branching in lateral olfactory tract is promoted by Nogo signaling

    PubMed Central

    Iketani, Masumi; Yokoyama, Takaakira; Kurihara, Yuji; Strittmatter, Stephen M.; Goshima, Yoshio; Kawahara, Nobutaka; Takei, Kohtaro

    2016-01-01

    Mitral cells are major projection neurons of the olfactory bulb (OB) that form an axonal bundle known as the lateral olfactory tract (LOT). After axonal bundle formation, collateral branches sprout from primary axons of the LOT. Recently, we identified LOT usher substance (LOTUS) as an endogenous Nogo receptor-1 (NgR1) antagonist and demonstrated that LOTUS contributes to the formation of the LOT axonal bundle. Immunoblots revealed that the expression level of Nogo-A in the OB developmentally increased during axonal collateral formation. Next, we found that the axonal collateral branches were increased in cultured OB neurons from LOTUS-knockout (KO) mice, whereas they were decreased in cultured OB neurons from NgR1-KO mice. Knockdown of Nogo-A in cultured OB neurons reduced the number of axonal collateral branches, suggesting that endogenous Nogo-A induces axonal branching. Finally, the collateral branches of the LOT were increased in LOTUS-KO mice, whereas those in NgR1-KO mice were decreased. Moreover, the abnormal increase of axonal branching observed in LOTUS-KO mice was rescued in the double mutant of LOTUS- and NgR1-KO mice. These findings suggest that Nogo-A and NgR1 interactions may contribute to axonal branching in LOT development. PMID:28000762

  5. 30 CFR 800.21 - Collateral bonds.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral...

  6. 30 CFR 800.21 - Collateral bonds.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral...

  7. 30 CFR 800.21 - Collateral bonds.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral...

  8. 30 CFR 800.21 - Collateral bonds.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral...

  9. 30 CFR 800.21 - Collateral bonds.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR BONDING AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS BOND AND INSURANCE REQUIREMENTS FOR SURFACE COAL MINING AND RECLAMATION OPERATIONS UNDER REGULATORY PROGRAMS § 800.21 Collateral...

  10. Collateral Learning and Mathematical Education of Teachers

    ERIC Educational Resources Information Center

    Abramovich, Sergei

    2012-01-01

    This article explores the notion of collateral learning in the context of classic ideas about the summation of powers of the first "n" counting numbers. Proceeding from the well-known legend about young Gauss, this article demonstrates the value of reflection under the guidance of "the more knowledgeable other" as a pedagogical method of making…

  11. 13 CFR 120.934 - Collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Collateral. 120.934 Section 120.934 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company... must be insured against such hazards and risks as SBA may require, with provisions for notice to...

  12. 12 CFR 614.4240 - Collateral definitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... satisfied the requirements for and has been certified as a real estate appraiser by a State or territory... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact.... (o) Real estate means an identified parcel or tract of land, including improvements, if any. (p)...

  13. 12 CFR 614.4240 - Collateral definitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... satisfied the requirements for and has been certified as a real estate appraiser by a State or territory... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact.... (o) Real estate means an identified parcel or tract of land, including improvements, if any. (p)...

  14. 12 CFR 614.4240 - Collateral definitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... satisfied the requirements for and has been certified as a real estate appraiser by a State or territory... income and/or other collateral, absent the real estate, and the decision to extend credit was, in fact.... (o) Real estate means an identified parcel or tract of land, including improvements, if any. (p)...

  15. Using Collateral Material To Improve Writing Performance.

    ERIC Educational Resources Information Center

    Taylor, Monica E.

    2003-01-01

    Examines the extent to which the provision of selected collateral material can enhance students' enjoyment of their writing tasks, and their performance in a context where although English is the official language, it is little used and much resisted by students for whom the language of choice for social interaction is the local Creole.…

  16. 28 CFR 104.47 - Collateral sources.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... compensation, including life insurance, pension funds, death benefits programs, and payments by Federal, State... determining the appropriate collateral source offset for future benefit payments, the Special Master may employ an appropriate methodology for determining the present value of such future benefits....

  17. 28 CFR 104.47 - Collateral sources.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 2 2011-07-01 2011-07-01 false Collateral sources. 104.47 Section 104.47 Judicial Administration DEPARTMENT OF JUSTICE (CONTINUED) SEPTEMBER 11TH VICTIM COMPENSATION FUND OF 2001..., or local governments related to the terrorist-related aircraft crashes of September 11, 2001....

  18. 12 CFR 950.7 - Collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... securities as the Finance Board in its discretion may determine. (2) Agency securities. Securities issued...: (i) Mortgage-backed securities issued or guaranteed by Freddie Mac, Fannie Mae, Ginnie Mae, or any... collateral has a readily ascertainable value, can be reliably discounted to account for liquidation and...

  19. Transluminal Angioplasty of Peroneal Artery Branches in Diabetics: Initial Technical Experience

    SciTech Connect

    Graziani, Lanfroi Silvestro, Antonio; Monge, Luca; Boffano, Gian Mario; Kokaly, Francesco; Casadidio, Ilaria; Giannini, Francesco

    2008-01-15

    The present study aimed to report the technical feasibility of percutaneous transluminal angioplasty (PTA) of obstructed or insufficient collateral branches (anterior and posterior perforating branches) from distal peroneal to foot arteries in diabetic patients with chronic critical limb ischemia (CLI) and chronic noncrossable occlusion of the anterior and posterior tibial arteries. Twenty-four diabetic CLI patients (age, 67 {+-} 8 years; 87% males) undergoing collateral PTA were included. Baseline clinical angiographic and follow-up data were retrospectively reviewed. Collateral PTA was associated with a concomitant PTA of other sites in 21 (83%) cases. In 15 cases the treated collateral linked the peroneal with the plantaris communis; in 9 cases, the peroneal with the dorsalis pedis. Angiographic results of collateral PTA were good in 13 cases (<30% residual stenosis), whereas the result was considered moderate (30%-49% residual stenosis) in the remaining cases. Neither perforation nor acute occlusion of the treated collaterals or other relevant complications were observed. Mean follow-up was 32 {+-} 17 months. Major amputation was necessary for two (8.3%) patients. Cumulative limb salvage rates at 2 and 4 years were 96% and 87%, respectively. In conclusion, this initial experience shows that PTA of the collateral branches from distal peroneal to foot arteries is a feasible technique. Future studies are required to define the clinical role of this novel approach.

  20. Local control of information flow in segmental and ascending collaterals of single afferents.

    PubMed

    Lomelí, J; Quevedo, J; Linares, P; Rudomin, P

    1998-10-08

    In the vertebrate spinal cord, the activation of GABA(gamma-amino-butyric acid)-releasing interneurons that synapse with intraspinal terminals of sensory fibres leading into the central nervous system (afferent fibres) produces primary afferent depolarization and presynaptic inhibition. It is not known to what extent these presynaptic mechanisms allow a selective control of information transmitted through specific sets of intraspinal branches of individual afferents. Here we study the local nature of the presynaptic control by measuring primary afferent depolarization simultaneously in two intraspinal collaterals of the same muscle spindle afferent. One of these collaterals ends at the L6-L7 segmental level in the intermediate nucleus, and the other ascends to segment L3 within Clarke's column, the site of origin of spinocerebellar neurons. Our results indicate that there are central mechanisms that are able to affect independently the synaptic effectiveness of segmental and ascending collaterals of individual muscle spindle afferents. Focal control of presynaptic inhibition thus allows the intraspinal branches of afferent fibres to function as a dynamic assembly that can be fractionated to convey information to selected neuronal targets. This may be a mechanism by which different spinal postsynaptic targets that are coupled by sensory input from a common source could be uncoupled.

  1. Preliminary analysis of the hydrologic effects of temporary shutdowns of the Rondout-West Branch Water Tunnel on the groundwater-flow system in Wawarsing, New York

    USGS Publications Warehouse

    Stumm, Frederick; Chu, Anthony; Como, Michael D.; Noll, Michael L.

    2012-01-01

    Flooding of streets and residential basements, and bacterial contamination of private-supply wells with Escherichia coli (E. coli) are recurring problems in the Rondout Valley near the Town of Wawarsing, Ulster County, New York. Leakage from the Rondout-West Branch (RWB) Water Tunnel and above-normal precipitation have been suspected of causing elevated groundwater levels and basement flooding. The hydrology of a 12-square-mile study area within the Town of Wawarsing was studied during 2008-10. A network of 41 wells (23 unconsolidated-aquifer and 18 bedrock wells) and 2 surface-water sites was used to monitor the hydrologic effects of four RWB Water Tunnel shutdowns. The study area is underlain by a sequence of northeast-trending sedimentary rocks that include limestone, shale, and sandstone. The bedrock contains dissolution features, fractures, and faults. Inflows that ranged from less than 1 to more than 9,000 gallons per minute from the fractured bedrock were documented during construction of the 13.5-foot-diameter RWB Water Tunnel through the sedimentary-rock sequence 710 feet (ft) beneath the study-area valley. Glacial sediments infill the valley above the bedrock sequence and consist of clay, silt, sand, and gravel. The groundwater-flow system in the valley consists of both fractured-rock and unconsolidated aquifers. Water levels in both the bedrock and unconsolidated aquifers respond to variations in seasonal precipitation. During the past 9 years (2002-10), annual precipitation at Central Park, N.Y., has exceeded the 141-year mean. Potentiometric-surface maps indicate that groundwater in the bedrock flows from the surrounding hills on the east and west sides of the valley toward the center of the valley, and ultimately toward the northeast. On average, water levels in the bedrock aquifer had seasonal differences of 5.3 ft. Analysis of hydrographs of bedrock wells indicates that many of these wells are affected by the RWB Tunnel leakage. Tunnel

  2. Collateral response to activation of potassium channels in vivo.

    PubMed

    Lamping, K G

    1998-04-01

    Activation of ATP-sensitive K+ channels is involved in the coronary vascular response to decreases in perfusion pressure and ischemia. Since activation of ATP-sensitive K+ channels in collateral vessels may be important in determining flow to collateral-dependent myocardium, the ability of collaterals to respond to activation of the channel was tested. In the beating heart of dogs, we compared responses of non-collaterals less than 100 microns in diameter to collaterals of similar size using computer-controlled stroboscopic epi-illumination of the left ventricle coupled to a microscope-video system. Aprikalim, a selective activator of ATP-sensitive K+ channels (0.1-10 microM) produced similar dose-dependent dilation of non-collaterals and collaterals. Relaxation was decreased by inhibition of ATP-sensitive K+ channels with glibenclamide, but not by inhibition of nitric oxide synthase with nitro-L-arginine. Bradykinin (10-100 microM) produced similar dilation of non-collaterals and collaterals which was decreased by nitro-L-arginine but not glibenclamide. Thus, in microvascular collaterals, relaxation to both nitric oxide and activation of ATP-sensitive K+ channels is similar to non-collaterals.

  3. Collateral Circulation in Chronic Total Occlusions - an interventional perspective.

    PubMed

    Choo, Gim-Hooi

    2015-09-09

    Human coronary collaterals are inter-coronary communications that are believed to be present from birth. In the presence of chronic total occlusions, recruitment of flow via these collateral anastomoses to the arterial segment distal to occlusion provide an alternative source of blood flow to the myocardial segment at risk. This mitigates the ischemic injury. Clinical outcome of coronary occlusion ie. severity of myocardial infarction/ischemia, impairment of cardiac function and possibly survival depends not only on the acuity of the occlusion, extent of jeopardized myocardium, duration of ischemia but also to the adequacy of collateral circulation. Adequacy of collateral circulation can be assessed by various methods. These coronary collateral channels have been used successfully as a retrograde access route for percutaneous recanalization of chronic total occlusions. Factors that promote angiogenesis and further collateral remodeling ie. arteriogenesis have been identified. Promotion of collateral growth as a therapeutic target in patients with no suitable revascularization option is an exciting proposal.

  4. Collateral Circulation in Chronic Total Occlusions - An Interventional Perspective

    PubMed Central

    Choo, Gim-Hooi

    2015-01-01

    Human coronary collaterals are inter-coronary communications that are believed to be present from birth. In the presence of chronic total occlusions, recruitment of flow via these collateral anastomoses to the arterial segment distal to occlusion provide an alternative source of blood flow to the myocardial segment at risk. This mitigates the ischemic injury. Clinical outcome of coronary occlusion ie. severity of myocardial infarction/ischemia, impairment of cardiac function and possibly survival depends not only on the acuity of the occlusion, extent of jeopardized myocardium, duration of ischemia but also to the adequacy of collateral circulation. Adequacy of collateral circulation can be assessed by various methods. These coronary collateral channels have been used successfully as a retrograde access route for percutaneous recanalization of chronic total occlusions. Factors that promote angiogenesis and further collateral remodeling ie. arteriogenesis have been identified. Promotion of collateral growth as a therapeutic target in patients with no suitable revascularization option is an exciting proposal.

  5. Acquired portosystemic collaterals: anatomy and imaging.

    PubMed

    Leite, Andréa Farias de Melo; Mota, Américo; Chagas-Neto, Francisco Abaeté; Teixeira, Sara Reis; Elias Junior, Jorge; Muglia, Valdair Francisco

    2016-01-01

    Portosystemic shunts are enlarged vessels that form collateral pathological pathways between the splanchnic circulation and the systemic circulation. Although their causes are multifactorial, portosystemic shunts all have one mechanism in common-increased portal venous pressure, which diverts the blood flow from the gastrointestinal tract to the systemic circulation. Congenital and acquired collateral pathways have both been described in the literature. The aim of this pictorial essay was to discuss the distinct anatomic and imaging features of portosystemic shunts, as well as to provide a robust method of differentiating between acquired portosystemic shunts and similar pathologies, through the use of illustrations and schematic drawings. Imaging of portosystemic shunts provides subclinical markers of increased portal venous pressure. Therefore, radiologists play a crucial role in the identification of portosystemic shunts. Early detection of portosystemic shunts can allow ample time to perform endovascular shunt operations, which can relieve portal hypertension and prevent acute or chronic complications in at-risk patient populations.

  6. Acquired portosystemic collaterals: anatomy and imaging*

    PubMed Central

    Leite, Andréa Farias de Melo; Mota Jr., Américo; Chagas-Neto, Francisco Abaeté; Teixeira, Sara Reis; Elias Junior, Jorge; Muglia, Valdair Francisco

    2016-01-01

    Portosystemic shunts are enlarged vessels that form collateral pathological pathways between the splanchnic circulation and the systemic circulation. Although their causes are multifactorial, portosystemic shunts all have one mechanism in common-increased portal venous pressure, which diverts the blood flow from the gastrointestinal tract to the systemic circulation. Congenital and acquired collateral pathways have both been described in the literature. The aim of this pictorial essay was to discuss the distinct anatomic and imaging features of portosystemic shunts, as well as to provide a robust method of differentiating between acquired portosystemic shunts and similar pathologies, through the use of illustrations and schematic drawings. Imaging of portosystemic shunts provides subclinical markers of increased portal venous pressure. Therefore, radiologists play a crucial role in the identification of portosystemic shunts. Early detection of portosystemic shunts can allow ample time to perform endovascular shunt operations, which can relieve portal hypertension and prevent acute or chronic complications in at-risk patient populations. PMID:27777479

  7. Dynamics of collateral circulation in progressive asymptomatic carotid disease.

    PubMed

    Moll, F L; Eikelboom, B C; Vermeulen, F E; van Lier, H J; Schulte, B P

    1986-03-01

    Inadequacy of collateral arterial flow is the major risk factor for hemispheric infarction in association with spontaneous occlusion of the ipsilateral carotid artery. This prospective study was designed to measure the adaptation of collateral cerebral circulation through the circle of Willis in patients in whom a unilateral carotid stenosis of hemodynamic consequence develops asymptomatically. The collateral cerebral potential is assessed by ocular pneumoplethysmography (OPG) during proximal common carotid artery compression, measuring the collateral ophthalmic artery pressure (COAP). During an average follow-up of almost 3 years (maximum more than 7 years), 45 patients showed asymptomatic development of a unilateral hemodynamically significant carotid stenosis according to OPG evidence. In these patients the mean index COAP/brachial artery pressure did not change on the side of stenosis progression (p greater than 0.05). The developed carotid stenosis had only reduced collateral circulation to the contralateral hemisphere. The risk of inadequate collateral cerebral circulation remained during progression of asymptomatic extracranial arterial obstructive disease.

  8. The fundamental theorem of asset pricing under default and collateral in finite discrete time

    NASA Astrophysics Data System (ADS)

    Alvarez-Samaniego, Borys; Orrillo, Jaime

    2006-08-01

    We consider a financial market where time and uncertainty are modeled by a finite event-tree. The event-tree has a length of N, a unique initial node at the initial date, and a continuum of branches at each node of the tree. Prices and returns of J assets are modeled, respectively, by a R2JxR2J-valued stochastic process . In this framework we prove a version of the Fundamental Theorem of Asset Pricing which applies to defaultable securities backed by exogenous collateral suffering a contingent linear depreciation.

  9. Pial Collateral Reactivity During Hypertension and Aging

    PubMed Central

    Chan, Siu-Lung; Sweet, Julie G.; Bishop, Nicole

    2016-01-01

    Background and Purpose— We investigated vasoactive properties of leptomeningeal arterioles (LMAs) under normotensive conditions and during hypertension and aging that are known to have poor collateral flow and little salvageable tissue. Methods— LMAs, identified as distal anastomotic arterioles connecting middle and anterior cerebral arteries, were studied isolated and pressurized from young (18 weeks) or aged (48 weeks) normotensive Wistar Kyoto (WKY18, n=14; WKY48, n=6) rats and spontaneously hypertensive rats (SHR18, n=16; SHR48, n=6). Myogenic tone and vasoactive responses to pressure as well as endothelial function and ion channel activity were measured. Results— LMAs from WKY18 had little myogenic tone at 40 mm Hg (8±3%) that increased in aged WKY48 (30±6%). However, LMAs from both WKY groups dilated to increased pressure and demonstrated little myogenic reactivity, a response that would be conducive to collateral flow. In contrast, LMAs from both SHR18 and SHR48 displayed considerable myogenic tone (56±8% and 43±7%; P<0.01 versus WKY) and constricted to increased pressure. LMAs from both WKY and SHR groups had similar basal endothelial nitric oxide and IK channel activity that opposed tone. However, dilation to sodium nitroprusside, diltiazem and 15 mmol/L KCl was impaired in LMAs from SHR18. Conclusions— This study shows for the first time that LMAs from young and aged SHR are vasoconstricted and have impaired vasodilatory responses that may contribute to greater perfusion deficit and little penumbral tissue. These results also suggest that therapeutic opening of pial collaterals is possible during middle cerebral artery occlusion to create penumbral tissue and prevent infarct expansion. PMID:27103017

  10. Collateral sensitivity of antibiotic-resistant microbes.

    PubMed

    Pál, Csaba; Papp, Balázs; Lázár, Viktória

    2015-07-01

    Understanding how evolution of microbial resistance towards a given antibiotic influences susceptibility to other drugs is a challenge of profound importance. By combining laboratory evolution, genome sequencing, and functional analyses, recent works have charted the map of evolutionary trade-offs between antibiotics and have explored the underlying molecular mechanisms. Strikingly, mutations that caused multidrug resistance in bacteria simultaneously enhanced sensitivity to many other unrelated drugs (collateral sensitivity). Here, we explore how this emerging research sheds new light on resistance mechanisms and the way it could be exploited for the development of alternative antimicrobial strategies.

  11. Branching Morphogenesis

    PubMed Central

    Horowitz, Arie; Simons, Michael

    2009-01-01

    Tubular structures are a fundamental anatomical theme recurring in a wide range of animal species. In mammals, tubulogenesis underscores the development of several systems and organs, including the vascular system, the lungs, and the kidneys. All tubular systems are hierarchical, branching into segments of gradually diminishing diameter. There are only two cell types that form the lumen of tubular systems – either endothelial cells in the vascular system, or epithelial cells in all other organs. The most important feature in determining the morphology of the tubular systems is the frequency and geometry of branching. Hence, deciphering the molecular mechanisms underlying the sprouting of new branches from pre-existing ones is the key to understanding the formation of tubular systems. The morphological similarity between the various tubular systems is underscored by similarities between the signaling pathways which control their branching. A prominent feature common to these pathways is their duality – an agonist counterbalanced by an inhibitor. The formation of the tracheal system in Drosophila melanogaster is driven by fibroblast growth factor (FGF) and inhibited by Sprouty/Notch. In vertebrates, the analogous pathways are FGF and transforming growth factor β in epithelial tubular systems, or vascular endothelial growth factor and Notch in the vascular system. PMID:19179661

  12. 48 CFR 48.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a)...

  13. 48 CFR 2448.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority...

  14. 48 CFR 2448.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority...

  15. Collateral Informant Assessment in Alcohol Use Research Involving College Students

    ERIC Educational Resources Information Center

    Hagman, Brett T.; Cohn, Amy M.; Noel, Nora E.; Clifford, Patrick R.

    2010-01-01

    Objective: This study examined the associations between college students' self-reported alcohol use and corresponding collateral reports and identified factors that influence agreement between both sets of reports. Participants/Methods: Subject-collateral pairs (N = 300) were recruited from undergraduate psychology courses. Results: Data yielded…

  16. 46 CFR 308.509 - Collateral deposit fund.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Collateral deposit fund. 308.509 Section 308.509 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund....

  17. Endothelial function in well-developed canine coronary collateral vessels.

    PubMed

    Altman, J; Dulas, D; Pavek, T; Laxson, D D; Homans, D C; Bache, R J

    1993-02-01

    This study examined responses of coronary collateral blood flow to endothelial-dependent vasodilators. Studies were performed in 13 dogs 4-6 mo after embolic occlusion of the left anterior descending coronary artery (LAD). Collateral flow was determined as the sum of retrograde flow from the cannulated LAD, and continuing tissue flow was measured with microspheres administered during the retrograde flow collection. Agonists were introduced into the left main coronary artery to reach collaterals arising from the left coronary arterial system. The endothelial-dependent vasodilators acetylcholine and bradykinin caused 21 +/- 7 and 25 +/- 8% increases of collateral flow, respectively (each P < 0.05). This was not different from the 28 +/- 8% increase in collateral flow produced by nitroglycerin. To determine whether vasodilator prostaglandins contributed to the increased collateral flow, studies were performed after cyclooxygenase blockade with indomethacin (5 mg/kg iv). Indomethacin caused a 30 +/- 9% decrease of retrograde flow during basal conditions but did not blunt the maximum collateral flow rates produced by acetylcholine, bradykinin, or nitroglycerin. These data demonstrate intact endothelial-dependent vasodilator mechanisms in the well-developed coronary collateral circulation.

  18. 12 CFR 614.4250 - Collateral evaluation standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... and procedures. Such a collateral evaluation shall be identified as either a collateral valuation or a...) Potential liabilities, including those associated with any hazardous waste or other environmental concerns... requested minimum valuation or specific valuation or approval of a loan. (b) For purposes of...

  19. 48 CFR 48.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 1 2013-10-01 2013-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a)...

  20. 48 CFR 48.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a)...

  1. 48 CFR 48.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 1 2012-10-01 2012-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a)...

  2. 48 CFR 48.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Sharing collateral savings. 48.104-3 Section 48.104-3 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT VALUE ENGINEERING Policies and Procedures 48.104-3 Sharing collateral savings. (a)...

  3. 48 CFR 2448.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority...

  4. 48 CFR 2448.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority...

  5. 48 CFR 2448.104-3 - Sharing collateral savings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Sharing collateral savings. 2448.104-3 Section 2448.104-3 Federal Acquisition Regulations System DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT CONTRACT MANAGEMENT VALUE ENGINEERING 2448.104-3 Sharing collateral savings. (a) The authority...

  6. 46 CFR 308.509 - Collateral deposit fund.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Collateral deposit fund. 308.509 Section 308.509 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund....

  7. 46 CFR 308.509 - Collateral deposit fund.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Collateral deposit fund. 308.509 Section 308.509 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund....

  8. 46 CFR 308.509 - Collateral deposit fund.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Collateral deposit fund. 308.509 Section 308.509 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund....

  9. 46 CFR 308.509 - Collateral deposit fund.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Collateral deposit fund. 308.509 Section 308.509 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo Insurance § 308.509 Collateral deposit fund....

  10. Assessment of collateral flow in patients with cerebrovascular disorders.

    PubMed

    Donahue, Joseph; Sumer, Suna; Wintermark, Max

    2014-10-01

    The ability to maintain cerebral parenchymal perfusion during states of acute or chronic ischemic insult depends largely on the capacity of the cerebral collateral circulation. Perfusion techniques, including perfusion-CT and arterial spin labeling, may not only describe the overall status of the collateral network, but can also quantify the pathophysiologic collateral reserve, which is occult to conventional imaging techniques. The following review details advanced imaging modalities capable of resolving pathophysiologic collateral circulation in a functional and dynamic manner, with regards to the evaluation of both acute ischemic penumbra and chronic cerebral vascular reserve. Specifically, the applications of perfusion-CT, arterial spin labeling MRI techniques, and transcranial Doppler are reviewed in the context of collateral circulation with emphasis on perfusion techniques and proposed clinical utility.

  11. Transcriptional changes in sensory ganglia associated with primary afferent axon collateral sprouting in spared dermatome model

    PubMed Central

    Harrison, Benjamin J.; Venkat, Gayathri; Hutson, Thomas; Rau, Kristofer K.; Bunge, Mary Bartlett; Mendell, Lorne M.; Gage, Fred H.; Johnson, Richard D.; Hill, Caitlin; Rouchka, Eric C.; Moon, Lawrence; Petruska, Jeffrey C.

    2015-01-01

    Primary afferent collateral sprouting is a process whereby non-injured primary afferent neurons respond to some stimulus and extend new branches from existing axons. Neurons of both the central and peripheral nervous systems undergo this process, which contributes to both adaptive and maladaptive plasticity (e.g., [1], [2], [3], [4], [5], [6], [7], [8], [9]). In the model used here (the “spared dermatome” model), the intact sensory neurons respond to the denervation of adjacent areas of skin by sprouting new axon branches into that adjacent denervated territory. Investigations of gene expression changes associated with collateral sprouting can provide a better understanding of the molecular mechanisms controlling this process. Consequently, it can be used to develop treatments to promote functional recovery for spinal cord injury and other similar conditions. This report includes raw gene expression data files from microarray experiments in order to study the gene regulation in spared sensory ganglia in the initiation (7 days) and maintenance (14 days) phases of the spared dermatome model relative to intact (“naïve”) sensory ganglia. Data has been deposited into GEO (GSE72551). PMID:26697387

  12. Interaction between Axons and Specific Populations of Surrounding Cells Is Indispensable for Collateral Formation in the Mammillary System

    PubMed Central

    Çankaya, Murat; Stoykova, Anastassia; Zhou, Xunlei; Alvarez-Bolado, Gonzalo

    2011-01-01

    Background An essential phenomenon during brain development is the extension of long collateral branches by axons. How the local cellular environment contributes to the initial sprouting of these branches in specific points of an axonal shaft remains unclear. Methodology/Principal Findings The principal mammillary tract (pm) is a landmark axonal bundle connecting ventral diencephalon to brainstem (through the mammillotegmental tract, mtg). Late in development, the axons of the principal mammillary tract sprout collateral branches at a very specific point forming a large bundle whose target is the thalamus. Inspection of this model showed a number of distinct, identified cell populations originated in the dorsal and the ventral diencephalon and migrating during development to arrange themselves into several discrete groups around the branching point. Further analysis of this system in several mouse lines carrying mutant alleles of genes expressed in defined subpopulations (including Pax6, Foxb1, Lrp6 and Gbx2) together with the use of an unambiguous genetic marker of mammillary axons revealed: 1) a specific group of Pax6-expressing cells in close apposition with the prospective branching point is indispensable to elicit axonal branching in this system; and 2) cooperation of transcription factors Foxb1 and Pax6 to differentially regulate navigation and fasciculation of distinct branches of the principal mammillary tract. Conclusions/Significance Our results define for the first time a model system where interaction of the axonal shaft with a specific group of surrounding cells is essential to promote branching. Additionally, we provide insight on the cooperative transcriptional regulation necessary to promote and organize an intricate axonal tree. PMID:21625468

  13. Collateral learning and mathematical education of teachers

    NASA Astrophysics Data System (ADS)

    Abramovich, Sergei

    2012-04-01

    This article explores the notion of collateral learning in the context of classic ideas about the summation of powers of the first n counting numbers. Proceeding from the well-known legend about young Gauss, this article demonstrates the value of reflection under the guidance of 'the more knowledgeable other' as a pedagogical method of making one's mathematics learning experience educative. This includes learning about the efficacy of generalizing by induction and the perils of overgeneralization. Recourse to geometry and computing as support system in understanding concepts of algebra is emphasized towards the end of promoting an experiential approach to mathematics. This article stems from the author's work with prospective teachers of secondary mathematics in a capstone course. Their reflections on the course are shared and analysed.

  14. Elevated Release of Beta-thromboglobulin and Platelet Factor 4 in Cerebral Infarction Patients with Branch Atheromatous Disease: A Preliminary Report.

    PubMed

    Yokote, Akiyoshi; Hashimoto, Kazutoshi; Bikei, Ryu; Nakamoto, Hidetoshi

    2015-01-01

    This study evaluated the levels of the platelet activation markers beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) in patients with branch atheromatous disease (BAD). Patients with newly diagnosed cerebral infarctions were recruited into the study; those with cardiogenic cerebral infarctions were excluded. Beta-TG and PF4 levels were measured before therapeutic intervention and compared between patients with and without BAD; Welch's t-test was used to determine significant differences between the groups. A total of 15 subjects were enrolled in the study, and 8 were diagnosed with BAD. Beta-TG (P = 0.031) and PF4 (P = 0.041) levels were significantly higher in the BAD patients than in the non-BAD patients. Platelet activity is normally elevated in patients with cerebral infarctions, but is elevated to an even greater extent in BAD patients. The evaluation of beta-TG and PF4 levels may be beneficial for the elucidation of BAD.

  15. Fault Branching

    NASA Astrophysics Data System (ADS)

    Dmowska, R.; Rice, J. R.; Poliakov, A. N.

    2001-12-01

    Theoretical stress analysis for a propagating shear rupture suggests that the propensity of the rupture path to branch is determined by rupture speed and by the preexisting stress state. See Poliakov, Dmowska and Rice (JGR, submitted April 2001, URL below). Deviatoric stresses near a mode II rupture tip are found to be much higher to both sides of the fault plane than directly ahead, when rupture speed becomes close to the Rayleigh speed. However, the actual pattern of predicted Coulomb failure on secondary faults is strongly dependent on the angle between the fault and the direction of maximum compression Smax in the pre-stress field. Steep Smax angles lead to more extensive failure on the extensional side, whereas shallow angles give comparable failure regions on both. Here we test such concepts against natural examples. For crustal thrust faults we may assume that Smax is horizontal. Thus nucleation on a steeply dipping plane, like the 53 ° dip for the 1971 San Fernando earthquake, is consistent with rupture path kinking to the extensional side, as inferred. Nucleation on a shallow dip, like for the 12 ° -18 ° of the 1985 Kettleman Hills event, should activate both sides, as seems consistent with aftershock patterns. Similarly, in a strike slip example, Smax is inferred to be at approximately 60 ° with the Johnson Valley fault where it branched to the extensional side onto the Landers-Kickapoo fault in the 1992 event, and this too is consistent. Further, geological examination of the activation of secondary fault features along the Johnson Valley fault and the Homestead Valley fault consistently shows that most activity occurs on the extensional side. Another strike-slip example is the Imperial Valley 1979 earthquake. The approximate Smax direction is north-south, at around 35 ° with the main fault, where it branched, on the extensional side, onto Brawley fault, again interpretable with the concepts developed.

  16. Use of collateral information to improve LANDSAT classification accuracies

    NASA Technical Reports Server (NTRS)

    Strahler, A. H. (Principal Investigator)

    1981-01-01

    Methods to improve LANDSAT classification accuracies were investigated including: (1) the use of prior probabilities in maximum likelihood classification as a methodology to integrate discrete collateral data with continuously measured image density variables; (2) the use of the logit classifier as an alternative to multivariate normal classification that permits mixing both continuous and categorical variables in a single model and fits empirical distributions of observations more closely than the multivariate normal density function; and (3) the use of collateral data in a geographic information system as exercised to model a desired output information layer as a function of input layers of raster format collateral and image data base layers.

  17. Pulmonary artery agenesis associated with coronary collaterals among adults.

    PubMed

    Darwazah, Ahmad K; Alhaddad, Imad A

    2016-07-16

    Unilateral agenesis of the pulmonary artery is a rare congenital anomaly, which commonly involves the right side. Cases are associated with systemic collaterals, that may also rarely arise from the coronary arteries.Two adult patients are presented with a right pulmonary artery agenesis associated with collaterals from the right coronary artery. The implications of such an anomaly on pulmonary artery pressure and lung pathology differs among both cases. The association of coronary collaterals is rare and its implication is variable among various patients.

  18. 13 CFR 120.1850 - Will the Collateral be held by SBA?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Will the Collateral be held by SBA... Loan Program) § 120.1850 Will the Collateral be held by SBA? Yes, SBA or its expressly authorized agent... all Collateral for SISMBD Loans in a custodial account. Certificates held as Collateral must be...

  19. Anatomical study of the lateral collateral ligament and its circumference structures in the human knee joint.

    PubMed

    Yan, Jun; Sasaki, Wataru; Hitomi, Jiro

    2010-02-01

    Thirty-six cadavers (55 sides) were used to observe the innervation of the lateral collateral ligament (LCL) and its circumference structures with gross anatomical and histological methods to clarify the cause of indistinct pain in the lateral part of the knee joint. The innervating branches of the LCL could be divided into three types: (1) from the muscular branch of the biceps femoris muscle at lower 1/3 level of the thigh; (2) from the common fibular nerve (CFN) at the higher level of the fossa poplitea; (3) from the CFN at the level of the caput fibular. Furthermore, the three branches could singly or plurally distribute to the LCL (six types). Two of the connecting tissue membranes surrounding the surface of LCL formed an incomplete sheath structure, and a shutting "gap" was observed between the two membranes. Fine peripheral nervous branches were also observed in the two of the membranes. On the other hand, three types of nerve endings in the LCL (Type I/Ruffini mechanoreceptor; Type III/Golgi mechanoreceptor; Type IV/free nerve ending) were observed, and their presence was consistent with the ankle joint of humans. Therefore, the innervation of the two membranes (to form the shutting gap) in the surface of LCL may be associated with an indistinct pain when the knee joint is damaged.

  20. Chronic stress impairs collateral blood flow recovery in aged mice.

    PubMed

    Lassance-Soares, Roberta M; Sood, Subeena; Chakraborty, Nabarun; Jhamnani, Sunny; Aghili, Nima; Nashin, Hajra; Hammamieh, Rasha; Jett, Marti; Epstein, Stephen E; Burnett, Mary Susan

    2014-11-01

    Chronic stress is associated with increased risk of cardiovascular diseases. Aging is also associated with vascular dysfunction. We hypothesize that chronic stress accelerates collateral dysfunction in old mice. Mice were subjected to either chronic social defeat (CSD) or chronic cold stress (CCS). The CSD mice were housed in a box inside an aggressor's cage and exposed to the aggressor. The CCS group was placed in iced water. After chronic stress, mice underwent femoral artery ligation (FAL) and flow recovery was measured. For the CSD group, appearance and use scores of the foot and a behavioral test were performed. CSD impaired collateral flow recovery after FAL. Further, stressed mice had greater ischemic damage, impaired foot function, and altered behavior. The CCS mice also showed impaired collateral flow recovery. Chronic stress causes hind limb collateral dysfunction in old mice, a conclusion reinforced by the fact that two types of stress produced similar changes.

  1. 7 CFR 4287.113 - Release of collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... used to reduce the guaranteed loan or to buy replacement collateral must be requested in writing by the lender and concurred in by the Agency in writing in advance of the release. A written evaluation will...

  2. Vasomotor responses of newly developed coronary collateral vessels.

    PubMed

    Kinn, J W; Altman, J D; Chang, M W; Bache, R J

    1996-08-01

    Well-developed coronary collateral vessels contain an abundant muscular media and can undergo active vasomotion. However, early after coronary occlusion, coronary collateral vessels are thin walled with little smooth muscle, suggesting that vasomotor capability might be limited. Consequently, this study determined whether newly developed coronary collateral vessels have active vasomotor activity and whether endothelial function in these newly developed vessels is impaired. Retrograde blood flow was measured as an index of coronary collateral blood flow approximately 2 wk after embolic occlusion of the anterior descending coronary artery of dogs. Agonists were administered into the left main coronary artery to reach collaterals originating from the left coronary system. Baseline retrograde blood flow was 25.1 +/- 2.7 ml/min and increased to 36.7 +/- 3.7 ml/min after nitroglycerin (6 micrograms.kg-1.min-1, P < 0.05). Cyclooxygenase blockade with indomethacin (5 mg/kg i.v.) decreased retrograde collateral blood flow to 16.8 +/- 2.3 ml/min (P < 0.05). Subsequent administration of acetylcholine increased retrograde flow to 29.4 +/- 3.7 ml/min (P < 0.05), indicating intact endothelium-mediated vasodilation. Inhibition of nitric oxide synthase with NG-nitro-L-arginine further decreased coronary collateral retrograde flow to 12.0 +/- 2.8 ml/min (P < 0.05) and markedly blunted the response to acetylcholine. These findings demonstrate substantial vasomotor capability even early during coronary collateral development and indicate that both nitric oxide and cyclooxygenase-dependent endothelial mechanisms are intact.

  3. Serotonin, atherosclerosis, and collateral vessel spasm

    NASA Technical Reports Server (NTRS)

    Hollenberg, N.

    1988-01-01

    Studies on animal models demonstrate that platelet products contribute to vascular spasm in ischemic syndromes and that this is reversible with administration of ketanserin and thromboxane synthesis inhibitors. Laboratory animals (dogs, rabbits, and rats) that had femoral artery ligations exhibited supersensitivity to serotonin within days in their collateral blood vessels. This supersensitivity lasted at least 6 months. The response to serotonin was reversed by ketanserin, but not by 5HT-1 antagonists. Supersensitivity does not extend to norepinephrine, and alpha blockers do not influence the response to serotonin. It appears that platelet activation by endothelial injury contributes to ischemia through blood vessel occlusion and vascular spasm. When platelet activation occurs in vivo, blood vessel occlusion and vascular spasm are reversible in part by using ketanserin or agents that block thromboxane synthesis or its action. Combining both classes of agents reverses spasm completely. These findings support existing evidence that platelet products contribute to vascular disease, and provide an approach to improved management with currently available pharmacologic agents.

  4. Pen Branch Fault Program

    SciTech Connect

    Price, V.; Stieve, A.L.; Aadland, R.

    1990-09-28

    Evidence from subsurface mapping and seismic reflection surveys at Savannah River Site (SRS) suggests the presence of a fault which displaces Cretaceous through Tertiary (90--35 million years ago) sediments. This feature has been described and named the Pen Branch fault (PBF) in a recent Savannah River Laboratory (SRL) paper (DP-MS-88-219). Because the fault is located near operating nuclear facilities, public perception and federal regulations require a thorough investigation of the fault to determine whether any seismic hazard exists. A phased program with various elements has been established to investigate the PBF to address the Nuclear Regulatory Commission regulatory guidelines represented in 10 CFR 100 Appendix A. The objective of the PBF program is to fully characterize the nature of the PBF (ESS-SRL-89-395). This report briefly presents current understanding of the Pen Branch fault based on shallow drilling activities completed the fall of 1989 (PBF well series) and subsequent core analyses (SRL-ESS-90-145). The results are preliminary and ongoing: however, investigations indicate that the fault is not capable. In conjunction with the shallow drilling, other activities are planned or in progress. 7 refs., 8 figs., 1 tab.

  5. Genomic deletion of malic enzyme 2 confers collateral lethality in pancreatic cancer.

    PubMed

    Dey, Prasenjit; Baddour, Joelle; Muller, Florian; Wu, Chia Chin; Wang, Huamin; Liao, Wen-Ting; Lan, Zangdao; Chen, Alina; Gutschner, Tony; Kang, Yaan; Fleming, Jason; Satani, Nikunj; Zhao, Di; Achreja, Abhinav; Yang, Lifeng; Lee, Jiyoon; Chang, Edward; Genovese, Giannicola; Viale, Andrea; Ying, Haoqiang; Draetta, Giulio; Maitra, Anirban; Wang, Y Alan; Nagrath, Deepak; DePinho, Ronald A

    2017-02-02

    The genome of pancreatic ductal adenocarcinoma (PDAC) frequently contains deletions of tumour suppressor gene loci, most notably SMAD4, which is homozygously deleted in nearly one-third of cases. As loss of neighbouring housekeeping genes can confer collateral lethality, we sought to determine whether loss of the metabolic gene malic enzyme 2 (ME2) in the SMAD4 locus would create cancer-specific metabolic vulnerability upon targeting of its paralogous isoform ME3. The mitochondrial malic enzymes (ME2 and ME3) are oxidative decarboxylases that catalyse the conversion of malate to pyruvate and are essential for NADPH regeneration and reactive oxygen species homeostasis. Here we show that ME3 depletion selectively kills ME2-null PDAC cells in a manner consistent with an essential function for ME3 in ME2-null cancer cells. Mechanistically, integrated metabolomic and molecular investigation of cells deficient in mitochondrial malic enzymes revealed diminished NADPH production and consequent high levels of reactive oxygen species. These changes activate AMP activated protein kinase (AMPK), which in turn directly suppresses sterol regulatory element-binding protein 1 (SREBP1)-directed transcription of its direct targets including the BCAT2 branched-chain amino acid transaminase 2) gene. BCAT2 catalyses the transfer of the amino group from branched-chain amino acids to α-ketoglutarate (α-KG) thereby regenerating glutamate, which functions in part to support de novo nucleotide synthesis. Thus, mitochondrial malic enzyme deficiency, which results in impaired NADPH production, provides a prime 'collateral lethality' therapeutic strategy for the treatment of a substantial fraction of patients diagnosed with this intractable disease.

  6. Ulnar Collateral Ligament Reconstruction of the Elbow

    PubMed Central

    Erickson, Brandon J.; Chalmers, Peter N.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.

    2015-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) is a common procedure in both professional and high-level athletes. Purpose: To determine the effect of technique and level of play with UCLR on return to sport (RTS). Hypothesis: When comparing different surgical techniques or preoperative level of sports participation, there is no difference in rate of RTS after UCLR. Study Design: Systematic review; Level of evidence, 4. Methods: A systematic review was registered with PROSPERO and performed following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines using 3 publicly available free databases. Therapeutic clinical outcome investigations reporting UCLR outcomes with level of evidence 1 through 4 were eligible for inclusion. All study, subject, and surgical technique demographics were analyzed and compared between continents and countries. Descriptive statistics were calculated, and 2-proportion 2-sample z-test calculators with α = .05 were used to compare RTS between level of play and technique. Results: Twenty studies (2019 patients/elbows; mean age, 22.13 ± 4 years; 97% male; mean follow-up, 39.9 ± 16.2 months) were included. The majority of patients were baseball players (94.5%), specifically pitchers (80%). The most common level of play was collegiate (44.6%). Palmaris longus (71.2%) and the American Sports Medicine Institute (ASMI) technique (65.6%) were the most common graft choice and surgical technique, respectively. There was a pooled 86.2% RTS rate, and 90% of players scored excellent/good on the Conway-Jobe scale. RTS rates were higher among collegiate athletes (95.5%) than either high school (89.4%, P = .023) or professional athletes (86.4%, P < .0001). RTS rates were higher for the docking technique (97.0%, P = .001) and the ASMI technique (93.3%, P = .0034) than the Jobe technique (66.7%). Conclusion: UCLR is performed most commonly in collegiate athletes. Collegiate athletes have the highest RTS rate

  7. How temporal evolution of intracranial collaterals in acute stroke affects clinical outcomes

    PubMed Central

    Paliwal, Prakash; Low, Adrian F.; Tay, Edgar L.W.; Gopinathan, Anil; Nadarajah, Mahendran; Ting, Eric; Venketasubramanian, Narayanaswamy; Seet, Raymond C.S.; Ahmad, Aftab; Chan, Bernard P.L.; Teoh, Hock L.; Soon, Derek; Rathakrishnan, Rahul; Sharma, Vijay K.

    2016-01-01

    Objective: We compared intracranial collaterals on pretreatment and day 2 brain CT angiograms (CTA) to assess their evolution and relationship with functional outcomes in acute ischemic stroke (AIS) patients treated with IV tissue plasminogen activator (tPA). Methods: Consecutive AIS patients who underwent pretreatment and day 2 CTA and received IV tPA during 2010–2013 were included. Collaterals were evaluated by 2 independent neuroradiologists using 3 predefined criteria: the Miteff system, the Maas system, and 20-point collateral scale by the Alberta Stroke Program Early CT Score methodology. We stratified our cohort by baseline pre-tPA state of their collaterals and by recanalization status of the primary vessel for analysis. Good outcomes at 3 months were defined by a modified Rankin Scale score of 0–1. Results: This study included 209 patients. Delayed collateral recruitment by any grading system was not associated with good outcomes. All 3 scoring systems showed that collateral recruitment on the follow-up CTA from a baseline poor collateral state was significantly associated with poor outcome and increased bleeding risk. When the primary vessel remained persistently occluded, collateral recruitment was significantly associated with worse outcomes. Interestingly, collateral recruitment was significantly associated with increased mortality in 2 of the 3 grading systems. Conclusions: Not all collateral recruitment is beneficial; delayed collateral recruitment may be different from early recruitment and can result in worse outcomes and higher mortality. Prethrombolysis collateral status and recanalization are determinants of how intracranial collateral evolution affects functional outcomes. PMID:26740681

  8. [On structure characteristics and mechanisms of channels and collaterals].

    PubMed

    Chen, Jun-De

    2009-04-01

    Recognition of traditional Chinese medicine for the structures of channels and collaterals is possibly related with the tactics of human early general medical study, characterized by "inner", sub-micro, entirety, etc. The mechanisms are possibly involved in direct communication pathway of the cell junction (specially keeping the relevant cellular direct communication relation in individual development), the extra-cellular matrix stress network system and its biophysical message transmission--force--meridian signs transformation--inter-cellular massage integration, and "generalization" of the structures and activities of channels and collaterals in acupuncture serum phenomenon, etc. Thus, the hypothesis of multi-factors about channel structures-mechanisms is proposed.

  9. Optimal management of ulnar collateral ligament injury in baseball pitchers

    PubMed Central

    Hibberd, Elizabeth E; Brown, J Rodney; Hoffer, Joseph T

    2015-01-01

    The ulnar collateral ligament stabilizes the elbow joint from valgus stress associated with the throwing motion. During baseball pitching, this ligament is subjected to tremendous stress and injury if the force on the ulnar collateral ligament during pitching exceeds the physiological limits of the ligament. Injuries to the throwing elbow in baseball pitchers result in significant time loss and typically surgical intervention. The purpose of this paper is to provide a review of current information to sports medicine clinicians on injury epidemiology, injury mechanics, injury risk factors, injury prevention, surgical interventions, nonsurgical interventions, rehabilitation, and return to play outcomes in baseball pitchers of all levels. PMID:26635490

  10. Vascular collateralization along ventriculoperitoneal shunt catheters in moyamoya disease.

    PubMed

    Singla, Amit; Lin, Ning; Ho, Allen L; Scott, R Michael; Smith, Edward R

    2013-06-01

    Surgically created openings such as bur holes can serve as avenues for the development of collateral blood supply to the brain in patients with moyamoya disease. When such collateralization occurs through preexisting shunt catheter sites, the potential exists for perioperative stroke if these vessels are damaged during revision of a ventricular catheter for shunt malfunction. In this paper the authors report on a series of patients with a history of ventriculoperitoneal (VP) shunts who later developed moyamoya disease and were found to have spontaneous transdural collateral vessels at ventricular catheter sites readily visualized on diagnostic angiography. A consecutive surgical series of 412 patients with moyamoya disease treated at Boston Children's Hospital from 1990 to 2010 were reviewed to identify patients with concomitant moyamoya and a VP shunt. The clinical records and angiograms of these patients were reviewed to determine the extent of bur hole collaterals through the shunt site. Three patients were identified who had VP shunts placed for hydrocephalus and subsequently developed moyamoya disease. All 3 patients demonstrated spontaneous transdural collaterals at the ventricular catheter bur hole, as confirmed by angiography during the workup for moyamoya disease. No patients required subsequent revision of their ventricular catheters following the diagnosis of moyamoya. All patients have remained stroke free and clinically stable following pial synangiosis. Although the association of moyamoya and shunted hydrocephalus is rare, it may present a significant potential problem for the neurosurgeon treating a shunt malfunction in this patient population, because shunt bur holes may become entry sites for the ingrowth of significant cortical transdural collateral blood supply to the underlying brain. Shunt revision might therefore be associated with an increased risk of postoperative stroke or operative-site hemorrhage in this population if this

  11. Ultrasound imaging versus morphopathology in cardiovascular diseases. Coronary collateral circulation and atherosclerotic plaque

    PubMed Central

    Baroldi, Giorgio; Bigi, Riccardo; Cortigiani, Lauro

    2005-01-01

    This review article is aimed at comparing the results of histopathological and clinical imaging studies to assess coronary collateral circulation in humans. The role of collaterals, as emerging from morphological studies in both normal and atherosclerotic coronary vessels, is described; in addition, present role and future perpectives of echocardiographic techniques in assessing collateral circulation are briefly summarized. PMID:15740620

  12. 45 CFR 1336.67 - Security and collateral: Responsibilities of the Loan Administrator.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) As a Credit Factor. The availability of collateral security normally is considered an important factor in making loans. The types and amount of collateral security required should be governed by the relative strengths and weaknesses of other credit factors. The taking of collateral as security should...

  13. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  14. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  15. 7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Warehouse-stored marketing assistance loan collateral... Marketing Assistance Loans § 1421.106 Warehouse-stored marketing assistance loan collateral. (a) A commodity may be pledged as collateral for a warehouse-stored marketing assistance loan in the...

  16. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  17. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Release of the honey pledged as collateral for a loan... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral for a loan. (a)(1) A producer shall not move or dispose of any honey pledged as collateral for a...

  18. 76 FR 31518 - Public Roundtable on the Protection of Cleared Swaps Customer Collateral

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-01

    ... COMMISSION 17 CFR Parts 22 and 190 Public Roundtable on the Protection of Cleared Swaps Customer Collateral... related to the protection of cleared swaps customer collateral described in the CFTC's notice of proposed rulemaking regarding the Protection of Cleared Swaps Customer Contracts and Collateral and...

  19. 7 CFR 762.142 - Servicing related to collateral.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 7 2014-01-01 2014-01-01 false Servicing related to collateral. 762.142 Section 762.142 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY, DEPARTMENT OF AGRICULTURE SPECIAL PROGRAMS GUARANTEED FARM LOANS § 762.142 Servicing related to...

  20. Embolization of nonvariceal portosystemic collaterals in transjugular intrahepatic portosystemic shunts

    SciTech Connect

    Bilbao, Jose Ignacio; Arias, Mercedes; Longo, Jesus Maria; Alejandre, Pedro Luis; Betes, Maria Teresa; Elizalde, Arlette Maria

    1997-03-15

    Percutaneous embolization of large portosystemic collaterals was performed in three patients following placement of a transjugular intrahepatic portosystemic shunt in order to improve hepatopetal portal flow. Improved hepatic portal perfusion was achieved in these cases, thereby theoretically reducing the risk of chronic hepatic encephalopathy.

  1. 41 CFR 105-55.014 - Liquidation of collateral.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Liquidation of collateral. 105-55.014 Section 105-55.014 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  2. Collateral effects of antibiotics on mammalian gut microbiomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotics are an essential component of the modern lifestyle. They improve our lives by treating disease, preventing disease, and in the case of agricultural animals by improving feed efficiency. However, antibiotic usage is not without collateral effects. The development and spread of antibiot...

  3. 41 CFR 105-55.014 - Liquidation of collateral.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false Liquidation of collateral. 105-55.014 Section 105-55.014 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  4. 7 CFR 3.15 - Liquidation of collateral.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 1 2013-01-01 2013-01-01 false Liquidation of collateral. 3.15 Section 3.15 Agriculture Office of the Secretary of Agriculture DEBT MANAGEMENT Standards for the Administrative Collection.... (b) When an agency learns that a bankruptcy petition has been filed with respect to a debtor,...

  5. 41 CFR 105-55.014 - Liquidation of collateral.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false Liquidation of collateral. 105-55.014 Section 105-55.014 Public Contracts and Property Management Federal Property Management Regulations System (Continued) GENERAL SERVICES ADMINISTRATION Regional Offices-General...

  6. 7 CFR 3.15 - Liquidation of collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Liquidation of collateral. 3.15 Section 3.15 Agriculture Office of the Secretary of Agriculture DEBT MANAGEMENT Standards for the Administrative Collection.... (b) When an agency learns that a bankruptcy petition has been filed with respect to a debtor,...

  7. 22 CFR 213.17 - Liquidation of collateral.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Liquidation of collateral. 213.17 Section 213.17 Foreign Relations AGENCY FOR INTERNATIONAL DEVELOPMENT CLAIMS COLLECTION Collection § 213.17... circumstances require judicial foreclosure. However, collection from other businesses, including liquidation...

  8. A Moyamoya Patient with Bilateral Consecutive Branch Retinal Vein Occlusion

    PubMed Central

    Güçlü, Hande; Gurlu, Vuslat Pelitli; Ozal, Sadık Altan; Esgin, Haluk

    2016-01-01

    ABSTRACT We describe a moyamoya (MMD) patient with bilateral consecutive branch retinal vein occlusion (BRVO). The patient had a medical history of severe headache, cranial haemorrhage, bilateral supraclinoid carotid artery occlusion, and “puff of smoke” collaterals on cerebral angiography and an encephalomyosynangiosis operation. On ophthalmic examination, he had superior temporal branch vein occlusion with intraretinal haemorrhage and visual acuity of 20/25 in the right eye. Twelve years later, he presented with superior temporal branch vein occlusion in the left eye and visual acuity of 20/60. The patient was initially treated with a dexamethasone intravitreal implant, and later intravitreal ranibizumab injections. We describe the first reported case of bilateral consecutive BRVO and management in MMD. PMID:27928391

  9. Chloride intracellular channel 4 is required for maturation of the cerebral collateral circulation.

    PubMed

    Lucitti, Jennifer L; Tarte, Natalie J; Faber, James E

    2015-10-01

    The number and diameter of native collaterals in tissues of healthy mice vary widely, resulting in large differences in tissue injury in occlusive diseases. Recent studies suggest similar variation may exist in humans. Collateral variation in mice is determined by genetic background-dependent differences in embryonic collateral formation, by variation in maturation of the nascent collaterals, and by environmental factors such as aging that cause collateral rarefaction in the adult. Recently, formation of the collateral circulation in the brain was found to involve a unique VEGF-A-dependent "arteriolar" angiogenic sprouting-like mechanism. Elsewhere, chloride intracellular protein 4 (CLIC4) was implicated but not investigated directly, prompting the present study. Deletion of Clic4 had no effect on embryonic collaterogenesis. However, during collateral maturation from embryonic day 18.5 to postnatal day 7, reduced mural cell investment was observed and excessive pruning of collaterals occurred. Growth in collateral diameter was reduced. This resulted in 50% fewer collaterals of smaller diameter in the adult and thus larger infarct volume after middle cerebral artery occlusion. During collateral maturation, CLIC4 deficiency resulted in reduced expression of Vegfr2, Vegfr1, Vegfc, and mural cell markers, but not notch-pathway genes. Overexpression of VEGF-A in Clic4(-/-) mice had no effect on collaterogenesis, but rescued the above defects in collateral maturation by preventing mural cell loss and collateral pruning, thus restoring collateral number and diameter and reducing stroke severity in the adult. CLIC4 is not required for collaterogenesis but is essential for perinatal maturation of nascent collaterals through a mechanism that supports VEGF signaling.

  10. Chloride intracellular channel 4 is required for maturation of the cerebral collateral circulation

    PubMed Central

    Lucitti, Jennifer L.; Tarte, Natalie J.

    2015-01-01

    The number and diameter of native collaterals in tissues of healthy mice vary widely, resulting in large differences in tissue injury in occlusive diseases. Recent studies suggest similar variation may exist in humans. Collateral variation in mice is determined by genetic background-dependent differences in embryonic collateral formation, by variation in maturation of the nascent collaterals, and by environmental factors such as aging that cause collateral rarefaction in the adult. Recently, formation of the collateral circulation in the brain was found to involve a unique VEGF-A-dependent “arteriolar” angiogenic sprouting-like mechanism. Elsewhere, chloride intracellular protein 4 (CLIC4) was implicated but not investigated directly, prompting the present study. Deletion of Clic4 had no effect on embryonic collaterogenesis. However, during collateral maturation from embryonic day 18.5 to postnatal day 7, reduced mural cell investment was observed and excessive pruning of collaterals occurred. Growth in collateral diameter was reduced. This resulted in 50% fewer collaterals of smaller diameter in the adult and thus larger infarct volume after middle cerebral artery occlusion. During collateral maturation, CLIC4 deficiency resulted in reduced expression of Vegfr2, Vegfr1, Vegfc, and mural cell markers, but not notch-pathway genes. Overexpression of VEGF-A in Clic4−/− mice had no effect on collaterogenesis, but rescued the above defects in collateral maturation by preventing mural cell loss and collateral pruning, thus restoring collateral number and diameter and reducing stroke severity in the adult. CLIC4 is not required for collaterogenesis but is essential for perinatal maturation of nascent collaterals through a mechanism that supports VEGF signaling. PMID:26276819

  11. Slit and Receptor Tyrosine Phosphatase 69D Confer Spatial Specificity to Axon Branching via Dscam1

    PubMed Central

    Dascenco, Dan; Erfurth, Maria-Luise; Izadifar, Azadeh; Song, Minmin; Sachse, Sonja; Bortnick, Rachel; Urwyler, Olivier; Petrovic, Milan; Ayaz, Derya; He, Haihuai; Kise, Yoshiaki; Thomas, Franziska; Kidd, Thomas; Schmucker, Dietmar

    2015-01-01

    SUMMARY Axonal branching contributes substantially to neuronal circuit complexity. Studies in Drosophila have shown that loss of Dscam1 receptor diversity can fully block axon branching in mechanosensory neurons. Here we report that cell-autonomous loss of the Receptor-Tyrosine-Phosphatase 69D (RPTP69D) and loss of midline-localized Slit inhibit formation of specific axon collaterals through modulation of Dscam1 activity. Genetic and biochemical data support a model in which direct binding of Slit to Dscam1 enhances the interaction of Dscam1 with RPTP69D, stimulating Dscam1 dephosphorylation. Single growth cone imaging reveals that Slit/RPTP69D are not required for general branch initiation, but instead promote the extension of specific axon collaterals. Hence, while regulation of intrinsic Dscam1-Dscam1 isoform interactions is essential for formation of all mechanosensory-axon branches, the local ligand-induced alterations of Dscam1 phosphorylation in distinct growth cone compartments enable the spatial specificity of axon collateral formation. PMID:26317474

  12. Intrahepatic Left to Right Portoportal Venous Collateral Vascular Formation in Patients Undergoing Right Portal Vein Ligation

    SciTech Connect

    Lienden, K. P. van; Hoekstra, L. T.; Bennink, R. J.; Gulik, T. M. van

    2013-12-15

    Purpose: We investigated intrahepatic vascular changes in patients undergoing right portal vein ligation (PVL) or portal vein embolization (PVE) in conjunction with the ensuing hypertrophic response and function of the left liver lobe. Methods: Between December 2008 and October 2011, 7 patients underwent right PVL and 14 patients PVE. Computed tomographic (CT) volumetry to assess future remnant liver (FRL) and functional hepatobiliary scintigraphy were performed in all patients before and 3 weeks after portal vein occlusion. In 18 patients an intraoperative portography was performed to assess perfusion through the occluded portal branches. Results: In all patients after initially successful PVL, reperfused portal veins were observed on CT scan 3 weeks after portal occlusion. This was confirmed in all cases during intraoperative portography. Intrahepatic portoportal collaterals were identified in all patients in the PVL group and in one patient in the PVE group. In all other PVE patients, complete occlusion of the embolized portal branches was observed on CT scan and on intraoperative portography. The median increase of FRL volume after PVE was 41.6 % (range 10-305 %), and after PVL was only 8.1 % (range 0-102 %) (p = 0.179). There were no differences in FRL function between both groups. Conclusion: Preoperative PVE and PVL are both methods to induce hypertrophy of the FRL in anticipation of major liver resection. Compared to PVE, PVL seems less efficient in inducing hypertrophy of the nonoccluded left lobe. This could be caused by the formation of intrahepatic portoportal neocollateral vessels, through which the ligated portal branches are reperfused within 3 weeks.

  13. Collateral Lethality: A new therapeutic strategy in oncology

    PubMed Central

    Muller, Florian L.; Aquilanti, Elisa A.; DePinho, Ronald A.

    2016-01-01

    Genomic deletion of tumor suppressor genes (TSG) is a rite of passage for virtually all human cancers. The synthetic lethal paradigm has provided a framework for the development of molecular targeted therapeutics that are functionally linked to the loss of specific TSG functions. In the course of genomic events that delete TSGs, a large number of genes with no apparent direct role in tumor promotion also sustain deletion as a result of chromosomal proximity to the target TSG. In this perspective, we review the novel concept of “collateral lethality”, which has served to identify cancer-specific therapeutic vulnerabilities resulting from co-deletion of passenger genes neighboring TSG. The large number of collaterally deleted genes, playing diverse functions in cell homeostasis, offers a rich repertoire of pharmacologically targetable vulnerabilities presenting novel opportunities for the development of personalized anti-neoplastic therapies. PMID:26870836

  14. Intracoronary demonstration of adenosine-induced coronary collateral steal.

    PubMed Central

    Seiler, C.; Kaufmann, U.; Meier, B.

    1997-01-01

    A steal phenomenon was detected by intravascular Doppler guidewire in a patient with a well collateralised coronary vascular area supplied by a reopened left circumflex coronary artery. This phenomenon accounted for the fall in blood flow velocity reserve during hyperaemic conditions to 50% of the baseline value. The collaterals must have been the cause of the steal phenomenon because complete revascularisation of the lesion barely reversed it. Images PMID:9038700

  15. Collateral Damage and the United States Air Force

    DTIC Science & Technology

    2007-11-02

    when a resource rich coalition conducts an air campaign against an inferior adversary, that coalition can discriminate in its application of...resource rich coalition conducts an air campaign against an inferior adversary, that coalition can discriminate in its application of airpower by... campaign .8 For that reason, it is logical for the strategist to possess a thorough awareness of the effects of potential and actual collateral

  16. Embryologicalic collateral venous channel on radionuclide liver/spleen study

    SciTech Connect

    Wilkinson, R.H. Jr.; Johnson, D.G.

    1983-07-01

    Obstruction of normal venous portal blood flow generally results in collateral circulation. The obstruction may be intrinsic t the vasculature (e.g., hepatic vein thrombosis, vascular anomalies) or it may be extravascular (e.g., cirrhosis, hepatic masses) and may effect blood flow by deforming and compressing the intrahepatic or splenoportal axis vessels. A technetium-99m sulfur colloid liver/spleen study demonstrates what is thought to be a functional paraumbilical or umbilical vein in a cirrhotic patient with portal hypertension.

  17. Regulation of native collateral vessel dilation after coronary occlusion in the dog.

    PubMed

    Lamping, K G; Bloom, E N; Harrison, D G

    1994-02-01

    The purpose of this study was to examine mechanisms involved in the response of native collaterals to coronary occlusion. In anesthetized dogs native collaterals were identified as vessels coursing between the left anterior descending and left circumflex arteries using fluorescence angiography. After a left anterior descending occlusion in 12 dogs, collaterals < 100 microns in diameter progressively dilated by 21 +/- 4% (n = 12) 1 min after occlusion and by 39 +/- 6% 15 min after occlusion. Collaterals > 100 microns in diameter did not dilate after coronary occlusion. NG-nitro-L-arginine (1 mg/min intracoronary) caused constriction under basal conditions in collaterals < 100 microns but did not prevent the dilation of collaterals after occlusion. In contrast, glibenclamide (10(-5) M), an inhibitor of ATP-sensitive potassium channels, had no effect on baseline diameter of collaterals < 100 microns diameter but completely prevented dilation of collaterals after occlusion. We conclude that collaterals are not maximally dilated immediately after a coronary occlusion but rather progressively dilate for at least 15 min after an occlusion. This dilation of native collaterals after an occlusion is not mediated by release of an endothelium-derived relaxing factor derived from L-arginine but is mediated by activation of ATP-sensitive K+ channels.

  18. The mechanism of coronary collateral vasoconstriction in response to cyclooxygenase blockade.

    PubMed

    Altman, J D; Bache, R J

    1994-02-01

    The present study was performed to examine the mechanism by which cyclooxygenase blockade produces vasoconstriction in well-developed coronary collateral vessels. Eight dogs were studied 4 to 6 months after occlusion of the left anterior descending coronary artery (LAD) had been performed to stimulate collateral vessel growth. At the time of study, the LAD was cannulated at the site of occlusion for measurement of retrograde blood flow as an index of collateral blood flow. Levels of 6-ketoprostaglandin F1 alpha were 32 +/- 13% higher in blood diverted from the collateral-dependent LAD than in aortic blood (P < .05); the increase in this stable product of prostacyclin metabolism indicated production of prostacyclin across the coronary collateral system. Administration of arachidonic acid into the left main coronary artery to reach collateral vessels entering the LAD resulted in a 21 +/- 6% increase in retrograde flow (P < .01), demonstrating cyclooxygenase activity with production of vasodilator prostaglandins in the collateral system. Ibuprofen (10 mg/kg IV) caused a 55 +/- 7% decrease in retrograde flow (P < .03), suggesting that cyclooxygenase blockade inhibited tonic production of vasodilator prostaglandins in the collateral system. In contrast, neither thromboxane synthase inhibition with dazmegrel nor thromboxane receptor blockade with SQ 30741 caused a significant change in collateral flow, thus failing to support thromboxane-induced collateral constriction. After cyclooxygenase blockade, prostacyclin infused into the left main coronary artery was able to restore retrograde flow to the preibuprofen level.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. FGF-4 gene therapy GENERX--Collateral Therapeutics.

    PubMed

    2002-01-01

    Collateral Therapeutics and Schering AG in Germany are developing a gene therapy product, GENERX for coronary artery disease. Based on the terms of the agreement, Schering or its affliates will be responsible for conducting and financing phase II/III clinical trials which are currently underway in the US and Europe. In particular, Berlex Labs (the US subsidiary of Schering AG), is involved in developing the gene therapy in the US. GENERX is an angiogenic gene therapy which triggers the production of a protein that stimulates new blood vessel growth providing an alternative route for blood to bypass clogged and blocked arteries in the heart. GENERX involves a one-time, non-surgical delivery of an adenovirus vector containing the human fibroblast growth factor-4 (FGF-4) into coronary arteries via a standard catheter. The FGF-4 gene was licensed from New York University. Collateral Therapeutics has been granted a US patent for "gene transfer-mediated angiogenesis therapy" for the nonsurgical administration of angiogenic genes for coronary and peripheral vascular disease. The patented technology has been licensed from the University of California. Collateral and Berlex have initiated pivotal phase IIb/III trials with GENERX in the US and Europe. The US-based study will evaluate the safety and efficacy of GENERX in patients with stable exertional angina due to coronary artery disease. The European-based study will evaluate patients with advanced coronary artery disease who are not considered candidates for interventions such as angioplasty and bypass surgery and/or patients who are unlikely to have positive outcomes from such interventions. Both studies, of a multicentre, randomised, double-blind and placebo-controlled design, will evaluate 2 dose levels of GENERX which will be non-surgically administered to the heart via intracoronary infusion through a standard cardiac catheter. Collateral also plans to develop a non-surgical gene therapy product using the FGF-4 gene

  20. Development of a NO biosensor and its application in research on channels and collaterals

    NASA Astrophysics Data System (ADS)

    Zhou, Yikai; Ren, Shu

    2001-09-01

    There are three parts in this paper. In the part 1 nitric oxide chemistry and the measurements of nitric oxide in biological models have been reviewed. In the part 2 the channels and collateral sand modern studies of the channels and collaterals have also ben reviewed and in part 3 a NO biosensor has been developed and it has been applied in the research of the channels and collaterals. Research results have confirmed that NO plays an important role in channel transmission.

  1. The Strategic and Political Impacts of Collateral Damage from Strike Warfare

    DTIC Science & Technology

    2015-03-01

    guided munitions. As the effects of collateral damage became much more visible because of mass media during the latter part of the twentieth century...Vietnamese’s ability to exploit collateral damage incidents in the media . Air commanders were not afforded the same freedoms they were in Korea because of...industrial capacity and population centers. With the growth of mass media after the Korean War, the effects of collateral damage started to become more

  2. Fate of coronary collateral circulation after aorto-coronary saphenous vein bypass grafts.

    PubMed Central

    Di Luzio, V; Roy, P R; Sowton, E; Dow, J

    1975-01-01

    The pre- and postoperative patterns of coronary artery collateral circulation have been studied in 34 patients who had saphenous vein bypass grafting. When the graft remained patent homocoronary collaterals could not be visualized after operation, but new intercoronary anastomoses frequently developed to other diseased arteries. When the graft and the bypassed artery were both obstructed there was a high incidence (5 out of 11) of myocardial infarction despite good preoperative collaterals. Images PMID:1079134

  3. A Comprehensive Review of Portosystemic Collaterals in Cirrhosis: Historical Aspects, Anatomy, and Classifications

    PubMed Central

    Shetty, Rajesh; Kasana, Vivek

    2016-01-01

    Portosystemic collateral formation in cirrhosis plays an important part in events that define the natural history in affected patients. A detailed understanding of collateral anatomy and hemodynamics in cirrhotics is essential to envisage diagnosis, management, and outcomes of portal hypertension. In this review, we provide detailed insights into the historical, anatomical, and hemodynamic aspects to portal hypertension and collateral pathways in cirrhosis with emphasis on the various classification systems. PMID:28074159

  4. Effect of the Interaction between Recanalization and Collateral Circulation on Functional Outcome in Acute Ischaemic Stroke

    PubMed Central

    Mangiafico, Salvatore; Saia, Valentina; Nencini, Patrizia; Romani, Ilaria; Palumbo, Vanessa; Pracucci, Giovanni; Consoli, Arturo; Rosi, Andrea; Renieri, Leonardo; Nappini, Sergio; Limbucci, Nicola; Inzitari, Domenico; Gensini, Gian Franco

    2014-01-01

    Summary Identification of patients with acute ischaemic stroke who could most benefit from arterial recanalization after endovascular treatment remains an unsettled issue. Although several classifications of collateral circulation have been proposed, the clinical role of collaterals is still debated. We evaluated the effect of the collateral circulation in relation to recanalization as a predictor of clinical outcome. Data were prospectively collected from 102 patients consecutively treated for proximal middle cerebral or internal carotid artery occlusion. The collateral circulation was evaluated with a novel semiquantitative-qualitative score, the Careggi collateral score (CCS), in six grades. Both CCS and recanalization grades (TICI) were analysed in relation to clinical outcome. A statistical analysis was performed to evaluate the effect of interaction between recanalization and collateral circulation on clinical outcome. Out of the 102 patients, 37 (36.3%) had poor collaterals, and 65 (63.7%) had good collaterals. Patients with good collaterals had lower basal National Institute of Health Stroke Scale (NIHSS), more distal occlusion, smaller lesions at 24h CT scan and better functional outcome. After multivariate analysis, the interaction between recanalization and collateral grades was significantly stronger as a predictor of good outcome (OR 6.87, 95% CI 2.11 – 22.31) or death (OR 4.66, 95%CI 1.48 – 14.73) compared to the effect of the single variables. Collaterals showed an effect of interaction with the recanalization grade in determining a favourable clinical outcome. Assessment of the collateral circulation might help predict clinical results after recanalization in patients undergoing endovascular treatment for acute ischaemic stroke. PMID:25496680

  5. A Comprehensive Review of Portosystemic Collaterals in Cirrhosis: Historical Aspects, Anatomy, and Classifications.

    PubMed

    Philips, Cyriac Abby; Arora, Ankur; Shetty, Rajesh; Kasana, Vivek

    2016-01-01

    Portosystemic collateral formation in cirrhosis plays an important part in events that define the natural history in affected patients. A detailed understanding of collateral anatomy and hemodynamics in cirrhotics is essential to envisage diagnosis, management, and outcomes of portal hypertension. In this review, we provide detailed insights into the historical, anatomical, and hemodynamic aspects to portal hypertension and collateral pathways in cirrhosis with emphasis on the various classification systems.

  6. Infarction Distribution Pattern in Acute Stroke May Predict the Extent of Leptomeningeal Collaterals

    PubMed Central

    Verma, Rajeev Kumar; Gralla, Jan; Klinger-Gratz, Pascal Pedro; Schankath, Adrian; Jung, Simon; Mordasini, Pasquale; Zubler, Christoph; Arnold, Marcel; Buehlmann, Monika; Lang, Matthias F.

    2015-01-01

    Objective The aim of this study was to evaluate whether the distribution pattern of early ischemic changes in the initial MRI allows a practical method for estimating leptomeningeal collateralization in acute ischemic stroke (AIS). Methods Seventy-four patients with AIS underwent MRI followed by conventional angiogram and mechanical thrombectomy. Diffusion restriction in Diffusion weighted imaging (DWI) and correlated T2-hyperintensity of the infarct were retrospectively analyzed and subdivided in accordance with Alberta Stroke Program Early CT score (ASPECTS). Patients were angiographically graded in collateralization groups according to the method of Higashida, and dichotomized in 2 groups: 29 subjects with collateralization grade 3 or 4 (well-collateralized group) and 45 subjects with grade 1 or 2 (poorly-collateralized group). Individual ASPECTS areas were compared among the groups. Results Means for overall DWI-ASPECTS were 6.34 vs. 4.51 (well vs. poorly collateralized groups respectively), and for T2-ASPECTS 9.34 vs 8.96. A significant difference between groups was found for DWI-ASPECTS (p<0.001), but not for T2-ASPECTS (p = 0.088). Regarding the individual areas, only insula, M1-M4 and M6 showed significantly fewer infarctions in the well-collateralized group (p-values <0.001 to 0.015). 89% of patients in the well-collateralized group showed 0–2 infarctions in these six areas (44.8% with 0 infarctions), while 59.9% patients of the poor-collateralized group showed 3–6 infarctions. Conclusion Patients with poor leptomeningeal collateralization show more infarcts on the initial MRI, particularly in the ASPECTS areas M1 to M4, M6 and insula. Therefore DWI abnormalities in these areas may be a surrogate marker for poor leptomeningeal collaterals and may be useful for estimation of the collateral status in routine clinical evaluation. PMID:26327519

  7. Combined Retrograde-Antegrade Arterial Recanalization Through Collateral Vessels: Redefinition of the Technique for Below-the-Knee Arteries

    SciTech Connect

    Graziani, L. Morelli, L. G.

    2011-02-15

    The effectiveness of below-the-knee PTA to obtain successful revascularization in patients with critical limb ischemia (CLI) has been well established, and many centers have adopted endovascular intervention as the first-line treatment in patients with chronic lower-extremity disease. The well-known complex and multilevel arterial disease in patients with CLI have lead to interventionists to continuously implement different technologies and techniques. The aim of the present study was to standardize and redefine a technique characterized for combined retrograde-antegrade recanalization of a native leg artery through a collateral arterial branch by using a single access. This concept has been well described in coronary arteries and recently in pelvic and tibial arteries.

  8. Detection of human collateral circulation by vasodilation-thallium-201 tomography

    SciTech Connect

    Nienaber, C.A.; Salge, D.; Spielmann, R.P.; Montz, R.; Bleifeld, W. )

    1990-04-15

    Coronary arteriolar vasodilation may provoke redistribution of flow to collateral-dependent jeopardized myocardium. To assess the physiologic significance of collaterals, 80 consecutive post-infarction patients (age 58 +/- 8 years) underwent vasodilation-redistribution thallium-201 tomographic imaging after administration of 0.56 mg of intravenous dipyridamole/kg body weight. Circumferential profile analysis of thallium-201 uptake and redistribution in representative left ventricular tomograms provided quantitative assessment of transient and fixed defects and separation between periinfarctional and distant inducible hypoperfusion. Tomographic perfusion data were correlated to wall motion and collateral circulation between distinct anatomic perfusion territories. Patients were grouped according to presence (59%) or absence (41%) of angiographically visible collateral channels to jeopardized myocardium. In the presence of collaterals, distant reversible defects were larger than in absence of collaterals (p less than 0.05); the extent of combined periinfarctional and distant redistribution was also larger in collateralized patients (p less than 0.025), whereas the size of the persistent perfusion defect was similar in both groups. By prospective analysis the tomographic perfusion pattern of combined periinfarctional and distant redistribution revealed a sensitivity of 85% and a specificity of 78% for the detection of significant collateral circulation in this group of patients. Thus, using the exhausted flow reserve as a diagnostic tool, vasodilation-thallium-201 tomography has the potential to identify and quantitate collateralized myocardium in post-infarction patients and may guide diagnostic and therapeutic decision-making.

  9. [A hypothesis about component model of substances of channels and collaterals].

    PubMed

    Lu, Liu-Sha

    2008-10-01

    The theory of channels and collaterals is a very important "substance" prop for the basic theories of TCM. After component model of substances of channels and collaterals is raised, according to the principle, structure and function are dialectical unity, the author finds in deeply research on a great number of completed experimental investigations of corresponding anatomic position of channels and collaterals and similar physiology at home and abroad that the difficult to understand TCM concepts such as "interdependence between yin and yang", "defensive energy" all could be displayed by the substance of body liquid showing liquid crystalline state during living of channels and collaterals.

  10. Sprouting of axonal collaterals after spinal cord injury is prevented by delayed axonal degeneration.

    PubMed

    Collyer, E; Catenaccio, A; Lemaitre, D; Diaz, P; Valenzuela, V; Bronfman, F; Court, F A

    2014-11-01

    After an incomplete spinal cord injury (SCI), partial recovery of locomotion is accomplished with time. Previous studies have established a functional link between extension of axon collaterals from spared spinal tracts and locomotor recovery after SCI, but the tissular signals triggering collateral sprouting have not been identified. Here, we investigated whether axonal degeneration after SCI contributes to the sprouting of collaterals from axons spared after injury. To this end, we evaluated collateral sprouting from BDA-labeled uninjured corticospinal axons after spinal cord hemisection (SCI(H)) in wild type (WT) mouse and Wld(S) mouse strains, which shows a significant delay in Wallerian degeneration after injury. After SCI(H), spared fibers of WT mice extend collateral sprouts to both intact and denervated sides of the spinal cord distant from the injury site. On the contrary, in the Wld(S) mice collateral sprouting from spared fibers was greatly reduced after SCI(H). Consistent with a role for collateral sprouting in functional recovery after SCI, locomotor recovery after SCI(H) was impaired in Wld(S) mice compared to WT animals. In conclusion, our results identify axonal degeneration as one of the triggers for collateral sprouting from the contralesional uninjured fibers after an SCI(H). These results open the path for identifying molecular signals associated with tissular changes after SCI that promotes collateral sprouting and functional recovery.

  11. Arterial supply, venous drainage and collateral circulation in the nose of the anaesthetized dog.

    PubMed

    Lung, M A; Wang, J C

    1987-10-01

    1. In pentobarbitone-anaesthetized dogs, nasal blood flows were measured with electromagnetic flow sensors. 2. The terminal internal maxillary artery was found to supply 22 +/- 2.2 ml min-1 (one side) to the nasal mucosa via the sphenopalatine and major palatine branches; the artery was found to receive multiple supply routes from common carotid, vertebral and subclavian arteries. 3. Nasal mucosa was found to receive collateral flow from contralateral terminal internal maxillary artery (about 5 to 10% of normal flow) and branches of subclavian arteries (about 36% of normal flow). 4. Nasal mucosa was found to have two venous systems: the low-flow (12 +/- 1.0 ml min-1; both sides) and low-pressure (7 +/- 0.6 mmHg) sphenopalatine veins draining the posterior nasal cavity and the high-flow (30 +/- 1.4 ml min-1; both sides) and high-pressure (17 +/- 1.0 mmHg) dorsal nasal veins draining the anterior nasal cavity. 5. PO2 of nasal venous blood was found to range from 62 +/- 2.9 mmHg to 65 +/- 3.4 mmHg. During nitrogen challenge to the nose, the sphenopalatine venous PO2 dropped to 35 +/- 3.0 mmHg while the dorsal nasal venous PO2 remained unchanged, suggesting that the sphenopalatine veins were responsible for draining capillary flow and dorsal nasal veins arteriovenous anastomotic flow as well. 6. Microscopic examination of the vascular casts confirmed that arteriovenous anastomoses were located only in the anterior nasal cavity.

  12. Enhancement of canine coronary collateral flow by nafazatrom.

    PubMed

    Fiedler, V B; Mardin, M

    1986-11-04

    The ability of oral nafazatrom treatment (10 mg/kg) 2 h preceding occlusion of the left anterior descending coronary artery for 6 h to limit expansion of myocardial injury was studied in anaesthetized canine hearts. Collateral blood flow was obtained with a load line analysis, employing aortic pressure, post-stenotic coronary pressure, and retrograde coronary flow from the occluded vessel. Contractile changes in the subendocardial ischemic perfused muscles were measured with ultrasonic techniques. Infarct size was determined post-mortem by a biochemical staining method and excision of necrosis. Post-stenotic coronary pressure was slightly below aortic pressure in both groups before coronary occlusion, and fell to 29 and 27% of aortic pressure in vehicle- and drug-treated hearts, respectively, after the insult. Retrograde flow was 2.4 +/- 0.6 vs. 4.1 +/- 0.7 ml/min in tylose- or nafazatrom-treated hearts. Collateral flow amounted to 1.5 +/- 0.06 vs. 2.5 +/- 0.04 ml/min in controls and drug-protected hearts. Contractility (dP/dtmax) and the %-segment shortening were greater in the ischaemic myocardium after nafazatrom treatment. Infarct size was 38 +/- 5.2 vs. 17 +/- 3.4 g/100 g left ventricle in the vehicle controls and nafazatrom group, respectively. Nafazatrom reduced infarct size by 46%. Besides other mechanisms, this was due to improved %-segment shortening and increased periinfarction collateral blood supply to jeopardized but viable myocardium. The drug may be of value in ischaemic heart disease as shown by the enhanced regional myocardial perfusion and improved contractility.

  13. Investigation of cerebral hemodynamics and collateralization in asymptomatic carotid stenoses.

    PubMed

    AlMuhanna, Khalid; Zhao, Limin; Kowalewski, Gregory; Beach, Kirk W; Lal, Brajesh K; Sikdar, Siddhartha

    2012-01-01

    Stroke is the second leading cause of death in the world, and one of the major causes of disability. Approximately 30% of ischemic strokes are due to plaque rupture in the carotid arteries. The most popular diagnostic method uses Doppler ultrasound to find the percent stenosis. However, other factors, such as the hemodynamics around the plaque may play a larger role in identifying the risk of plaque rupture. It has been shown previously in simulations that non-collateral flow in the circle of Willis (COW) could cause an increase of the intraluminal velocity around carotid plaque. This added strain may increase the vulnerability of the plaque to rupture. We investigated asymmetries in flow waveforms in the middle cerebral artery (MCA) in asymptomatic patients with carotid artery stenosis. We compared clinical results of velocity waveforms in the MCA, acquired using transcranial Doppler (TCD), with a simple linear simulation model of the intra- and extracranial arterial network to investigate the relationship between contralateral and ipsilateral flow profiles in the MCA for patients with asymptomatic carotid stenosis. In 17 out of 23 patients we found waveforms consistent with those predicted for a collateralized COW, with minimal differences in delay, velocity magnitude and resistivity index. In 6 cases, some unexpected findings were noted, such as large delays for 2 patients ≤ 50% stenosis, and a large velocity difference with low delay for 4 patients. More studies are needed to elucidate the role of incomplete intracranial collateralization on the hemodynamics around carotid plaque and to use imaging of the COW to corroborate our results.

  14. Melons are Branched Polymers

    NASA Astrophysics Data System (ADS)

    Gurau, Razvan; Ryan, James P.

    2014-11-01

    Melonic graphs constitute the family of graphs arising at leading order in the 1/N expansion of tensor models. They were shown to lead to a continuum phase, reminiscent of branched polymers. We show here that they are in fact precisely branched polymers, that is, they possess Hausdorff dimension 2 and spectral dimension 4/3.

  15. Nox2 and p47(phox) modulate compensatory growth of primary collateral arteries.

    PubMed

    DiStasi, Matthew R; Unthank, Joseph L; Miller, Steven J

    2014-05-15

    The role of NADPH oxidase (Nox) in both the promotion and impairment of compensatory collateral growth remains controversial because the specific Nox and reactive oxygen species involved are unclear. The aim of this study was to identify the primary Nox and reactive oxygen species associated with early stage compensatory collateral growth in young, healthy animals. Ligation of the feed arteries that form primary collateral pathways in rat mesentery and mouse hindlimb was used to assess the role of Nox during collateral growth. Changes in mesenteric collateral artery Nox mRNA expression determined by real-time PCR at 1, 3, and 7 days relative to same-animal control arteries suggested a role for Nox subunits Nox2 and p47(phox). Administration of apocynin or Nox2ds-tat suppressed collateral growth in both rat and mouse models, suggesting the Nox2/p47(phox) interaction was involved. Functional significance of p47(phox) expression was assessed by evaluation of collateral growth in rats administered p47(phox) small interfering RNA and in p47(phox-/-) mice. Diameter measurements of collateral mesenteric and gracilis arteries at 7 and 14 days, respectively, indicated no significant collateral growth compared with control rats or C57BL/6 mice. Chronic polyethylene glycol-conjugated catalase administration significantly suppressed collateral development in rats and mice, implying a requirement for H2O2. Taken together, these results suggest that Nox2, modulated at least in part by p47(phox), mediates early stage compensatory collateral development via a process dependent upon peroxide generation. These results have important implications for the use of antioxidants and the development of therapies for peripheral arterial disease.

  16. Plasma Catestatin: A Useful Biomarker for Coronary Collateral Development with Chronic Myocardial Ischemia

    PubMed Central

    Xu, Weixian; Yu, Haiyi; Li, Weihong; Gao, Wei; Guo, Lijun; Wang, Guisong

    2016-01-01

    Backgrounds Catestatin is an endogenous multifunctional neuroendocrinepeptide. Recently, catestatin was discovered as a novel angiogenic cytokine. The study was to investigate the associations between endogenous catestatin and coronary collateral development among the patients with chronic myocardial ischemia. Methods Thirty-eight patients with coronary artery chronic total occlusions (CTO) (CTO group) and 38 patients with normal coronary arteries (normal group) were enrolled in the series. Among the patients with CTO, coronary collateral development was graded according to the Rentrop score method. Rentrop score 0–1 collateral development was regarded as poor collateral group and 2–3 collateral development was regarded as good collateral group. Plasma catestatin level and vascular endothelial growth factor (VEGF) were measured by ELISA kits. Results The plasma catestatin levels in CTO group were significantly higher than that in normal group (1.97±1.01 vs 1.36±0.97ng/ml, p = 0.009). In the CTO group, the patients with good collateral development had significantly higher catestatin and VEGF levels than those with poor collateral development (2.36±0.73 vs 1.61±1.12 ng/ml, p = 0.018; 425.23±140.10 vs 238.48±101.00pg/mL, p<0.001). There is a positive correlation between plasma catestatin levels and Rentrop scores (r = 0.40, p = 0.013) among the patients with CTO. However, there is no correlations between plasma catestatin levels and VEGF (r = -0.06, p = 0.744). In the multiple linear regression models, plasma catestatin level was one of the independent factors of coronary collateral development after adjustment for confounders. Conclusions Plasma catestatin was associated with coronary collateral developments. It may be a useful biomarker for coronary collateral development and potential target for therapeutic angiogenesis in patients with CTO. PMID:27304618

  17. 10 CFR 609.16 - Perfection of liens and preservation of collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 609.16 Section 609.16 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS LOAN GUARANTEES FOR PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.16 Perfection of liens and preservation of collateral....

  18. 10 CFR 609.15 - Default, demand, payment, and collateral liquidation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Default, demand, payment, and collateral liquidation. 609.15 Section 609.15 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS LOAN GUARANTEES FOR PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.15 Default, demand, payment, and collateral...

  19. 12 CFR 723.7 - What are the collateral and security requirements?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 false What are the collateral and security requirements? 723.7 Section 723.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS MEMBER BUSINESS LOANS § 723.7 What are the collateral and security requirements? (a)...

  20. 12 CFR 723.7 - What are the collateral and security requirements?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false What are the collateral and security requirements? 723.7 Section 723.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS MEMBER BUSINESS LOANS § 723.7 What are the collateral and security requirements? (a)...

  1. 12 CFR 723.7 - What are the collateral and security requirements?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false What are the collateral and security requirements? 723.7 Section 723.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS MEMBER BUSINESS LOANS § 723.7 What are the collateral and security requirements? (a)...

  2. 12 CFR 723.7 - What are the collateral and security requirements?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false What are the collateral and security requirements? 723.7 Section 723.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS MEMBER BUSINESS LOANS § 723.7 What are the collateral and security requirements? (a)...

  3. 12 CFR 723.7 - What are the collateral and security requirements?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 false What are the collateral and security requirements? 723.7 Section 723.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS MEMBER BUSINESS LOANS § 723.7 What are the collateral and security requirements? (a)...

  4. Comparison of Alcoholics' Self-Reports of Drinking Behavior with Reports of Collateral Informants.

    ERIC Educational Resources Information Center

    Maisto, Stephen A.; And Others

    1979-01-01

    Posthospitalization follow-up data were collected from 52 alcoholic subjects and their collateral informants. Findings suggest that alcoholics who have been hospitalized for detoxification generally provide reliable self-reports of their posttreatment drinking behavior, and that gathering data from collateral informants is an effective method for…

  5. 7 CFR 1980.334 - Appraisal of property serving as collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Appraisal of property serving as collateral. 1980.334... Appraisal of property serving as collateral. An appraisal of all property serving as security for the... Lender may pass the cost of the appraisal on to the borrower. The appraisal must have been...

  6. 7 CFR 1980.444 - Appraisal of property serving as collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Appraisal of property serving as collateral. 1980.444... Program § 1980.444 Appraisal of property serving as collateral. (a) Appraisal reports prepared by... the appraisal to be made by a qualified appraiser on the lender's staff with experience appraising...

  7. 10 CFR 611.108 - Perfection of liens and preservation of collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Perfection of liens and preservation of collateral. 611.108 Section 611.108 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS ADVANCED TECHNOLOGY... determines are required to preserve the collateral. The cost of such contracts may be charged to the Borrower....

  8. Noninvasive assessment of coronary collaterals in man by PET perfusion imaging

    SciTech Connect

    Demer, L.L.; Gould, K.L.; Goldstein, R.A.; Kirkeeide, R.L. )

    1990-03-01

    At present, coronary collateralization cannot be identified or assessed noninvasively in patients. In animal studies, coronary collaterals are associated with coronary steal, defined as a regional fall in perfusion during coronary arteriolar vasodilation. To determine the effect of coronary arteriolar vasodilation on collateral bed perfusion in man, myocardial perfusion imaging was performed before and after pharmacologic coronary vasodilation in patients with coronary artery disease (CAD). Regional myocardial activity of {sup 82}Rb or {sup 13}N ammonia was measured by positron emission tomography (PET) at rest and with intravenous dipyridamole/handgrip stress in 28 patients with angiographic collaterals and in 25 control patients with similar CAD severity by quantitative arteriography. Regional myocardial activity decreased after dipyridamole, indicating coronary steal, in 25 of 28 patients with angiographic collaterals and in only 4 of 25 control patients without angiographic collaterals. These findings suggest that developed collaterals are associated with myocardial steal in patients with CAD, allowing potential use of PET for non-invasive identification of coronary collateralization.

  9. Excimer laser coronary atherectomy in septal collaterals during retrograde recanalization of a chronic total occlusion

    PubMed Central

    Ohlow, Marc-Alexander; Lotze, Ullrich; Lauer, Bernward

    2011-01-01

    Management of chronic total occlusions has been refined through the development of a retrograde approach via collateral pathways. We describe here the use of excimer laser coronary atherectomy in the septal collaterals. This appraoch was not yet described in the literature. PMID:22355487

  10. Factors associated with client-collateral agreement in substance abuse post-treatment self-reports.

    PubMed

    Kedia, Satish; Perry, Stephanie W

    2005-07-01

    This study examined levels of agreement and directionality of disagreement between the post-treatment self-reports of substance abuse clients and their collaterals. The study population comprised 1252 clients with a primary or secondary diagnosis of substance abuse or dependence whose treatment was publicly funded in Tennessee. Client and collateral responses to 13 questions were analyzed for levels of agreement, revealing the following: (a) levels of client-collateral agreement were high, at least 75% agreement on all 13 questions and at least 88% agreement on 10 variables; (b) a Simple Kappa Test confirmed that 11 out of 13 items had moderate to excellent nonchance agreement; (c) there was no consistent trend in directionality, that is, clients neither reported information more positively nor more negatively than their collaterals did; (d) on average, those collaterals who were spouses, parents, and children agreed more with clients compared to other types of collaterals; and (e) those collaterals who saw the clients more frequently and more recently had higher agreement than those who saw the clients less frequently. This research reaffirms that collaterals are a valuable source for verifying the accuracy of clients' self-reports and that this approach continues to hold considerable promise for substance abuse post-treatment assessment.

  11. Materials Test Branch

    NASA Technical Reports Server (NTRS)

    Gordon, Gail

    2012-01-01

    The Materials Test Branch resides at Marshall Space Flight Center's Materials and Processing laboratory and has a long history of supporting NASA programs from Mercury to the recently retired Space Shuttle. The Materials Test Branch supports its customers by supplying materials testing expertise in a wide range of applications. The Materials Test Branch is divided into three Teams, The Chemistry Team, The Tribology Team and the Mechanical Test Team. Our mission and goal is to provide world-class engineering excellence in materials testing with a special emphasis on customer service.

  12. Influence on collateral flow of recanalising chronic total coronary occlusions: a case-control study

    PubMed Central

    Pohl, T; Hochstrasser, P; Billinger, M; Fleisch, M; Meier, B; Seiler, C

    2001-01-01

    OBJECTIVE—To assess the effect of recanalisation on collateral flow in a case-control study in patients with and without chronic total coronary occlusions.
DESIGN—In 54 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) (mean (SD) age 61 (6) years), coronary collateral flow was measured by intracoronary pressure or Doppler guide wires at the end of repeated balloon occlusions. Coronary collateral flow index (collateral flow relative to normal antegrade flow) during the first two balloon inflations in 27 patients with a chronic total occlusion (occlusion group) was compared with that of 27 patients matched for age, sex, and collateral flow index at the first occlusion and with a coronary artery diameter stenosis ⩽ 80% (stenosis group).
RESULTS—Following revascularisation, collateral flow index decreased in 17 of the patients in the occlusion group (63%) and in eight of the patients in the stenosis group (30%) (p = 0.03 between groups). The overall change of collateral flow index between the first and the second balloon occlusion was −0.04 (0.01) in the occlusion group (p = 0.07 for paired comparison; from 0.29 (0.17) to 0.25 (0.14)), and +0.02 (0.06) in the stenosis group (p = 0.06 for paired comparison; from 0.27 (0.13) to 0.30 (0.15)). The trend to collateral enhancement in the stenosis group differed significantly from the occlusion group (p = 0.01).
CONCLUSIONS—While repeated coronary balloon occlusions induce collateral recruitment in the majority of patients with moderate stenoses, recanalisation of chronic total coronary occlusions is more often associated with collateral flow reduction. A later decrease in collateral flow by involution of collateral channels cannot be excluded by this study but has not been reported so far.


Keywords: coronary collateral circulation; coronary occlusion; revascularisation; collateral damage PMID:11559686

  13. Clinicopathologic correlation of retinal to choroidal venous collaterals of the optic nerve head.

    PubMed

    Schatz, H; Green, W R; Talamo, J H; Hoyt, W F; Johnson, R N; McDonald, H R

    1991-08-01

    An optic nerve meningioma developed in an elderly woman and was followed for 13 years until her death. The optic nerve was initially normal. Over time it became swollen and then atrophic and developed retinal venous to choroidal venous collaterals. Five hundred serial sections were prepared through the optic nerve and for approximately 1.5 mm superiorly and inferiorly to the optic nerve to trace the course of the collaterals that were seen ophthalmoscopically and angiographically in the optic nerve head. This clinicopathologic study shows clearly that the abnormal channels are, in fact, retinal venous to choroidal venous collaterals (bypass channels). Four collaterals extended around the end of Bruch's membrane at the optic nerve head. Two more collaterals extended through the retinal pigment epithelium to become continuous with a subretinal pigment epithelial neovascular membrane, the vessels of which connected with the choroidal vessels through a defect in Bruch's membrane.

  14. Chloride intracellular channel-4 is a determinant of native collateral formation in skeletal muscle and brain.

    PubMed

    Chalothorn, Dan; Zhang, Hua; Smith, Jennifer E; Edwards, John C; Faber, James E

    2009-07-02

    The capacity of the collateral circulation to lessen injury in occlusive vascular disease depends on the density and caliber of native (preexisting) collaterals, as well as their ability to outwardly remodel in ischemia. Native collateral conductance varies widely among healthy individuals, yet little is known about what specifies collateral formation. Chloride intracellular channel (CLIC)4 protein is required for endothelial cell hollowing, a process necessary for vessel formation during embryogenesis and ischemia. Whether CLIC4 has other physiological roles in vascular biology is uncertain. We studied collateral formation and remodeling in mice deficient in CLIC1 and CLIC4. Vascular responses to femoral artery ligation were similar in Clic1(-/-) and wild-type mice. In contrast, immediately after ligation perfusion dropped more in Clic4(-/-) than wild-type mice, suggesting fewer preexisting collaterals, a finding confirmed by angiography, greater ischemia, and worse recovery of perfusion; however, collateral remodeling was unaffected. Likewise, native cerebral collateral density in Clic4(-/-) (but not Clic1(-/-)) mice was reduced, resulting in severe infarctions. This was associated with impaired perinatal formation and stabilization of nascent collaterals. Clic4 hemizygous mice had intermediate deficits in the above parameters, suggesting a gene-dose effect. Ischemia augmented CLIC1 and CLIC4 expression similarly in wild-type mice. However, CLIC1 increased 3-fold more in Clic4(-/-) mice, suggesting compensation. Despite greater ischemia in Clic4(-/-) mice, hypoxia-inducible factor-1alpha, vascular endothelial growth factor (VEGF) and angiopoietin-2 increased less compared to wild-type, suggesting CLIC4 exerts influences upstream of hypoxia-inducible factor-1alpha-VEGF signaling. Hence, CLIC4 represents the second gene that, along with VEGF shown by us previously, specifies native collateral formation.

  15. Collateral vessel number, plaque burden, and functional decline in peripheral artery disease.

    PubMed

    McDermott, Mary M; Carr, James; Liu, Kiang; Kramer, Christopher M; Yuan, Chun; Tian, Lu; Criqui, Michael H; Guralnik, Jack M; Ferrucci, Luigi; Zhao, Lihui; Xu, Dongxiang; Kibbe, Melina; Berry, Jarett; Carroll, Timothy J

    2014-08-01

    Associations of collateral vessels and lower extremity plaque with functional decline are unknown. Among people with peripheral artery disease (PAD), we determined whether greater superficial femoral artery (SFA) plaque burden combined with fewer lower extremity collateral vessels was associated with faster functional decline, compared to less plaque and/or more numerous collateral vessels. A total of 226 participants with ankle-brachial index (ABI) <1.00 underwent magnetic resonance imaging of lower extremity collateral vessels and cross-sectional imaging of the proximal SFA. Participants were categorized as follows: Group 1 (best), maximum plaque area < median and collateral vessel number ≥6 (median); Group 2, maximum plaque area < median and collateral vessel number <6; Group 3, maximum plaque area > median and collateral vessel number ≥6; Group 4 (worst), maximum plaque area > median and collateral vessel number <6. Functional measures were performed at baseline and annually for 2 years. Analyses adjust for age, sex, race, comorbidities, and other confounders. Annual changes in usual-paced walking velocity were: Group 1, +0.01 m/s; Group 2, -0.02 m/s; Group 3, -0.01 m/s; Group 4, -0.05 m/s (p-trend=0.008). Group 4 had greater decline than Group 1 (p<0.001), Group 2 (p=0.029), and Group 3 (p=0.010). Similar trends were observed for fastest-paced 4-meter walking velocity (p-trend=0.018). Results were not substantially changed when analyses were repeated with additional adjustment for ABI. However, there were no associations of SFA plaque burden and collateral vessel number with decline in 6-minute walk. In summary, a larger SFA plaque burden combined with fewer collateral vessels is associated with a faster decline in usual and fastest-paced walking velocity in PAD.

  16. The association of circulating monocyte count with coronary collateral growth in patients with diabetes mellitus.

    PubMed

    Kocaman, Sinan Altan; Sahinarslan, Asife; Akyel, Ahmet; Timurkaynak, Timur; Boyaci, Bulent; Cengel, Atiye

    2010-03-01

    The status of inflammation may affect the collateral development in patients with diabetes mellitus (DM). Monocytes were found to have an important role in collateral growth in animal studies. We aimed to investigate the possible association of circulating monocyte count with collateral development in patients with DM and severe coronary artery disease (CAD). We enrolled 134 consecutive patients with DM who had > or =95 stenosis in at least one major coronary artery and investigated the relationship between circulating monocyte count and collateral growth. When we analyzed the coronary angiograms of eligible patients, we found that 64 of them had good collateral growth and 70 had poor collateral growth according to the Cohen-Rentrop method. The monocyte count was significantly different between good and poor collateral growth groups (643 +/- 184 vs. 479 +/- 143 per mm(3), P < 0.001). In the analysis comparing the Rentrop score with the Gensini score and circulating monocyte count, we found significant correlations (r = 0.293, P = 0.001 and r = 0.455, P < 0.001, respectively). The duration of ischemic symptoms tended to be longer in the good collateral group (1.9 +/- 4.1 vs. 0.8 +/- 1.3 years, P = 0.079). The Gensini score was also correlated with the duration of myocardial ischemic symptoms (r = 0.299, P = 0.004). Multivariate analysis revealed an increased monocyte count in the good collateral group [odds ratio (OR), 5.726; 95% confidence interval (CI), 1.817-18.040, P = 0.003, the cut-off value for monocyte was defined as 550 cell/mm(3)]. The increased circulating monocyte count in diabetic patients was evidently related to good coronary collateral growth. This finding may be potentially important in clinical and basic cardiovascular medicine.

  17. [Synopsis about the hypothesis of "information channel" of channel-collateral system].

    PubMed

    Chang, Xi-Lang

    2008-10-01

    The author of the present paper founded a theorem about the "incompleteness of single channel structure" (nerve, blood vessel, lymphatic, interspace, aperture, etc.) through quantitative and qualitative analysis about the economic information channel in the human body, which eliminates the probability of single channel structure in the information channel of channel (meridian)-collateral system. After comprehensive analysis on the current researches, the author puts forward a neodoxy, i.e., the body "information channel" structure of the channel-collateral system, mainly follows the distribution regularity of systemic statistics, and is not a single specific entity; various layers of the information channel in the main stems of the channel-collaterals are composed of optimized structure tissues. Hence, the structure of this information channel of channel-collateral system is an overall-optimized, sequential and compatible systemic structure. From this neodoxy, the author brings forward a working principle of channel-collaterals, which is supported theoretically by bio-auxology. The longitudinal distribution of the main stems of meridian-collaterals is considered to result from that in the process of the animal evolution, in the animals moving forward, the microscopic complicated movement of intracorporeal information and energy molecules is related to the forward macroscopic and non-uniform movement of organism in trans-measure. Its impulse and kinetic momentum forms a main vector in the longitudinal direction of the body (the direction of the main stem of channel-collaterals). In order to adapt to and utilize natural regularities, the main stems of the channel-collaterals gradually differentiate and evolve in the living organism, forming a whole system. The "hypothesis of biological origin of channel-collateral system" and "that of information channel of the channel-collaterals in the body" constitute a relatively complete theoretical system framework.

  18. Technical activities of the configuration aeroelasticity branch

    NASA Technical Reports Server (NTRS)

    Cole, Stanley R. (Editor)

    1991-01-01

    A number of recent technical activities of the Configuration Aeroelasticity Branch of the NASA Langley Research Center are discussed in detail. The information on the research branch is compiled in twelve separate papers. The first of these topics is a summary of the purpose of the branch, including a full description of the branch and its associated projects and program efforts. The next ten papers cover specific projects and are as follows: Experimental transonic flutter characteristics of supersonic cruise configurations; Aeroelastic effects of spoiler surfaces mounted on a low aspect ratio rectangular wing; Planform curvature effects on flutter of 56 degree swept wing determined in Transonic Dynamics Tunnel (TDT); An introduction to rotorcraft testing in TDT; Rotorcraft vibration reduction research at the TDT; A preliminary study to determine the effects of tip geometry on the flutter of aft swept wings; Aeroelastic models program; NACA 0012 pressure model and test plan; Investigation of the use of extension twist coupling in composite rotor blades; and Improved finite element methods for rotorcraft structures. The final paper describes the primary facility operation by the branch, the Langley TDT.

  19. On Minkowskian branching structures

    NASA Astrophysics Data System (ADS)

    Wroński, Leszek; Placek, Tomasz

    In Belnap's [Branching space-time. Synthese, 92, 385-434. 'Postprint' archived at http://philsci-archive.pitt.edu/archive/00001003] theory of branching space-times (BST) Our World's possible histories are thought of as space-times, yet the theory has models in which histories do not resemble relativistic space-times or any other physical space-times. The aim of this paper is to define a certain class of BST models, called 'Minkowskian Branching Structures' (MBSs), in which histories are isomorphic to Minkowski space-time. By focusing on these models rather than on general BST models, we hope that one may be able to improve on earlier BST analyses of physical phenomena. Also, introducing MBSs sets the stage for recent discussions about whether or not branching is physically feasible.

  20. The Olive Branch Awards.

    ERIC Educational Resources Information Center

    Harnack, William

    1984-01-01

    The first annual Olive Branch Awards, sponsored by the Writers' and Publishers Alliance and the Editors' Organizing Committee, were given to ten magazines, out of 60 that submitted entries. Winning entries are described briefly. (IM)

  1. 12 CFR 223.41 - What covered transactions are exempt from the quantitative limits and collateral requirements?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... quantitative limits and collateral requirements? 223.41 Section 223.41 Banks and Banking FEDERAL RESERVE SYSTEM... are exempt from the quantitative limits and collateral requirements? The following transactions are not subject to the quantitative limits of §§ 223.11 and 223.12 or the collateral requirements of §...

  2. 26 CFR 1.6049-7 - Returns of information with respect to REMIC regular interests and collateralized debt obligations.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... regular interests and collateralized debt obligations. 1.6049-7 Section 1.6049-7 Internal Revenue INTERNAL... collateralized debt obligations. (a) Definition of interest—(1) In general. For purposes of section 6049(a), for... with respect to a collateralized debt obligation (as defined in paragraph (d)(2) of this section),...

  3. 26 CFR 1.6049-7 - Returns of information with respect to REMIC regular interests and collateralized debt obligations.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... regular interests and collateralized debt obligations. 1.6049-7 Section 1.6049-7 Internal Revenue INTERNAL... collateralized debt obligations. (a) Definition of interest—(1) In general. For purposes of section 6049(a), for... with respect to a collateralized debt obligation (as defined in paragraph (d)(2) of this section),...

  4. Inferior Phrenic Arteries and Their Branches, Their Anatomy and Possible Clinical Importance: An Experimental Cadaver Study

    PubMed Central

    Gürses, İlke Ali; Gayretli, Özcan; Kale, Ayşin; Öztürk, Adnan; Usta, Ahmet; Şahinoğlu, Kayıhan

    2015-01-01

    Background: Transcatheter arterial chemoembolization is a common treatment for patients with inoperable hepatocellular carcinoma. If the carcinoma is advanced or the main arterial supply, the hepatic artery, is occluded, extrahepatic collateral arteries may develop. Both, right and left inferior phrenic arteries (RIPA and LIPA) are the most frequent and important among these collaterals. However, the topographic anatomy of these arteries has not been described in detail in anatomy textbooks, atlases and most previous reports. Aims: To investigate the anatomy and branching patterns of RIPA and LIPA on cadavers and compare our results with the literature. Study Design: Descriptive study. Methods: We bilaterally dissected 24 male and 2 female cadavers aged between 49 and 88 years for this study. Results: The RIPA and LIPA originated as a common trunk in 5 cadavers. The RIPA originated from the abdominal aorta in 13 sides, the renal artery in 2 sides, the coeliac trunk in 1 side and the left gastric artery in 1 side. The LIPA originated from the abdominal aorta in 9 sides and the coeliac trunk in 6 sides. In 6 cadavers, the ascending and posterior branches of the LIPA had different sources of origin. Conclusion: As both the RIPA and LIPA represent the half of all extrahepatic arterial collaterals to hepatocellular carcinomas, their anatomy gains importance not only for anatomists but interventional radiologists as well. PMID:26167344

  5. Photoionization of Endohedral Atoms: Collective, Reflective and Collateral Emissions

    NASA Astrophysics Data System (ADS)

    Chakraborty, Himadri S.; McCune, Matthew A.; Madjet, Mohamed E.; Hopper, Dale E.; Manson, Steven T.

    2009-12-01

    The photoionization properties of a fullerene-confined atom differ dramatically from that of an isolated atom. In the low energy region, where the fullerene plasmons are active, the electrons of the confined atom emerge through a collective channel carrying a significant chunk of plasmon with it. The photoelectron angular distribution of the confined atom however shows far lesser impact of the effect. At higher energies, the interference between two single-electron ionization channels, one directly from the atom and another reflected off the fullerene cage, producuces oscillatory cross sections. But for the outermost atomic level, which transfers some electrons to the cage, oscillations are further modulated by the collateral emission from the part of the atomic charge density transferred to the cage. These various modes of emissions are studied for the photoionization of Ar endohedrally confined in C60.

  6. Current Concepts in Rehabilitation Following Ulnar Collateral Ligament Reconstruction

    PubMed Central

    Ellenbecker, Todd S.; Wilk, Kevin E.; Altchek, David W.; Andrews, James R.

    2009-01-01

    Injuries to the ulnar collateral ligament (UCL) in throwing athletes frequently occurs from the repetitive valgus loading of the elbow during the throwing motion, which often results in surgical reconstruction of the UCL requiring a structured postoperative rehabilitation program. Several methods are currently used and recommended for UCL reconstruction using autogenous grafts in an attempt to reproduce the stabilizing function of the native UCL. Rehabilitation following surgical reconstruction of the UCL begins with range of motion and initial protection of the surgical reconstruction, along with resistive exercise for the entire upper extremity kinetic chain. Progressions for resistive exercise are followed that attempt to fully restore strength and local muscular endurance in the rotator cuff and scapular stabilizers, in addition to the distal upper extremity musculature, to allow for a return to throwing and overhead functional activities. Rehabilitation following UCL reconstruction has produced favorable outcomes, allowing for a return to throwing in competitive environments. PMID:23015887

  7. Medial collateral ligament reconstruction in the baseball Pitcher's elbow.

    PubMed

    Erne, Holger C; Zouzias, Ioannis C; Rosenwasser, Melvin P

    2009-08-01

    Pitchers are prone to elbow injuries because of high and repetitive valgus stresses on the elbow. The anterior bundle of the medial ulnar collateral ligament (MCL) of the elbow is the primary restraint and is often attenuated with time, leading to functional incompetence and ultimate failure. Pitchers with a history of medial elbow pain, reduced velocity, and loss of command may have an MCL injury in evolution. Physical examination and imaging can confirm the diagnosis. Treatment begins with rest and activity modification. All medial elbow pain is not MCL injury. Surgery is considered only for talented athletes who wish to return to competitive play and may include elite scholastic and other collegiates and professionals. The technique for MCL reconstruction was first described in 1986. Many variations have been offered since then, which can result in predictable outcomes, allowing many to return to the same level of competitive play.

  8. Photoionization of Endohedral Atoms: Collective, Reflective and Collateral Emissions

    SciTech Connect

    Chakraborty, Himadri S.; McCune, Matthew A.; Hopper, Dale E.; Madjet, Mohamed E.; Manson, Steven T.

    2009-12-03

    The photoionization properties of a fullerene-confined atom differ dramatically from that of an isolated atom. In the low energy region, where the fullerene plasmons are active, the electrons of the confined atom emerge through a collective channel carrying a significant chunk of plasmon with it. The photoelectron angular distribution of the confined atom however shows far lesser impact of the effect. At higher energies, the interference between two single-electron ionization channels, one directly from the atom and another reflected off the fullerene cage, producuces oscillatory cross sections. But for the outermost atomic level, which transfers some electrons to the cage, oscillations are further modulated by the collateral emission from the part of the atomic charge density transferred to the cage. These various modes of emissions are studied for the photoionization of Ar endohedrally confined in C{sub 60}.

  9. Modeling and simulation for collateral damage estimation in combat

    NASA Astrophysics Data System (ADS)

    Gordon, Steven C.; Martin, Douglas D.

    2005-05-01

    Modeling and simulation (M&S) is increasingly used for decision support during combat operations: M&S is going to war! One of the key operational uses of M&S in combat is collateral damage estimation (CDE). Reducing undesired collateral damage (CD) in war and in operations other than war is important to the United States of America. Injuries to noncombatants and damage to protected sites are uniformly avoided by our forces whenever possible in planning and executing combat operations. This desire to limit unwanted CD presents unique challenges to command and control (C2), especially for time-sensitive targeting (TST). The challenges begin the moment a target is identified because CD estimates must meet specified criteria before target approval is granted. Therefore, CDE tools must be accurate, responsive, and human-factored, with graphics that aid C2 decisions. This paper will describe how CDE tools are used to build three-dimensional models of potential target areas and select appropriate munitions, fusing, and delivery in order to minimize predicted CD. The paper will cover the evolution of CDE from using only range rings around the target to improvements through Operation Allied Force, Operation Enduring Freedom, and Operation Iraqi Freedom. Positive CDE feedback from various sources, including the Secretary of Defense, lessons learned, and warfighters will be presented. Current CDE tools in the field and CDE tools used in reachback are being improved, and short-term and long-term improvements in those tools and in the CDE methodology will be described in this paper.

  10. The fissure: interlobar collateral ventilation and implications for endoscopic therapy in emphysema.

    PubMed

    Koster, Theodoor David; Slebos, Dirk-Jan

    2016-01-01

    In patients with severe emphysema, bronchoscopic lung volume reduction using one-way valves is a promising therapeutic option to improve lung function and quality of life. The goal of this treatment is to achieve a complete lobar atelectasis. In a significant proportion of patients, this atelectasis cannot be achieved due to interlobar collateral ventilation. This collateral ventilation is generated through incomplete lobar fissures. Therefore, only patients with complete fissures and no collateral ventilation can be selected for endobronchial therapy with one-way valves. Incomplete fissures are very common and exhibit a great variation in anatomy. The reported prevalence is 17%-85% for the right major fissure, 19%-74% for the left major fissure, and 20%-90% for the minor fissure. There are several methods of measuring or predicting the presence of collateral ventilation, with computed tomography (CT)-fissure analysis and the Chartis measurement being the most important. CT-fissure analysis is an indirect method to measure the completeness of fissures as a surrogate for collateral ventilation. The Chartis system is an endobronchial method to directly measure the presence of collateral ventilation. Both methods have unique value, and the combination of both can accurately predict the treatment response to the bronchoscopic placement of endobronchial valves. This review provides an in-depth view of lung fissure and collateral ventilation to help understand its importance in selecting the appropriate patients for new emphysema treatments and thus avoid useless treatment in unsuitable patients.

  11. Effect of cyclooxygenase blockade on blood flow through well-developed coronary collateral vessels.

    PubMed

    Altman, J; Dulas, D; Bache, R J

    1992-06-01

    Collateral vessels that develop after coronary artery occlusion demonstrate perivascular inflammation, subintimal hyperplasia, and endothelial proliferation. This study was performed to test the hypothesis that these abnormalities are associated with evidence for increased production of vasodilator prostaglandins. Eight dogs were studied 4-6 months after occlusion of the anterior descending coronary artery had been performed to stimulate collateral vessel growth. At the time of study, the anterior descending coronary artery was cannulated at the site of occlusion to allow measurement of retrograde blood flow as an index of interarterial collateral flow. Injection of radioactive microspheres during the retrograde flow collection allowed determination of continuing tissue flow in the collateral-dependent zone as an index of intramural microvascular collateral flow. Retrograde and tissue flows were measured before and 20 minutes after 5 mg/kg i.v. indomethacin, a dose that caused 95 +/- 3% inhibition of the coronary vasodilation in response to a 500 micrograms intracoronary bolus of arachidonic acid. Heart rate and mean aortic pressure were not significantly altered by indomethacin, and blood flow to the normally perfused myocardial region was not changed by administration of indomethacin. However, indomethacin caused a 40 +/- 7% decrease in retrograde flow (p less than 0.01), and microvascular collateral flow to the dependent myocardium decreased by 20 +/- 10% (p less than 0.05). These data indicate that, unlike the normal coronary circulation, well-developed coronary collateral vessels are under the tonic influence of vasodilator prostaglandins.

  12. Collateral blood flow in different cerebrovascular hierarchy provides endogenous protection in cerebral ischemia.

    PubMed

    Luo, Chuanming; Liang, Fengyin; Ren, Huixia; Yao, Xiaoli; Liu, Qiang; Li, Mingyue; Qin, Dajiang; Yuan, Ti-Fei; Pei, Zhong; Su, Huanxing

    2016-11-15

    Collateral blood flow as vascular adaptions to focal cerebral ischemia is well recognized. However, few studies directly investigate the dynamics of collateral vessel recruitment in vivo and little is known about the effect of collateral blood flow in different cerebrovascular hierarchy on the neuropathology after focal ischemic stroke. Here, we report that collateral blood flow is critically involved in blood vessel compensations following regional ischemia. We occluded a pial arteriole using femtosecond laser ablating under the intact thinned skull and documented the changes of collateral flow around the surface communication network and between the surface communication network and subsurface microcirculation network using in vivo two photon microscopy imaging. Occlusion of the pial arteriole apparently increased the diameter and collateral blood flow of its leptomeningeal anastomoses, which significantly reduced the cortical infarction size. This result suggests that the collateral flow via surface communicating network connected with leptomeningeal anastomoses could greatly impact on the extent of infarction. We then further occluded the target pial arteriole and all of its leptomeningeal anastomoses. Notably, this type of occlusion led to reversals of blood flow in the penetrating arterioles mainly proximal to the occluded pial arteriole in a direction from the subsurface microcirculation network to surface arterioles. Interesting, the cell death in the area of ischemic penumbra was accelerated when we performed occlusion to cease the reversed blood flow in those penetrating arterioles, suggesting that the collateral blood flow from subsurface microcirculation network exerts protective roles in delaying cell death in the ischemic penumbra. In conclusion, we provide the first experimental evidence that collateral blood vessels at different cerebrovascular hierarchy are endogenously compensatory mechanisms in brain ischemia. This article is protected by

  13. Damage Tolerance Assessment Branch

    NASA Technical Reports Server (NTRS)

    Walker, James L.

    2013-01-01

    The Damage Tolerance Assessment Branch evaluates the ability of a structure to perform reliably throughout its service life in the presence of a defect, crack, or other form of damage. Such assessment is fundamental to the use of structural materials and requires an integral blend of materials engineering, fracture testing and analysis, and nondestructive evaluation. The vision of the Branch is to increase the safety of manned space flight by improving the fracture control and the associated nondestructive evaluation processes through development and application of standards, guidelines, advanced test and analytical methods. The Branch also strives to assist and solve non-aerospace related NDE and damage tolerance problems, providing consultation, prototyping and inspection services.

  14. Pen Branch delta expansion

    SciTech Connect

    Nelson, E.A.; Christensen, E.J.; Mackey, H.E.; Sharitz, R.R.; Jensen, J.R.; Hodgson, M.E.

    1984-02-01

    Since 1954, cooling water discharges from K Reactor ({anti X} = 370 cfs {at} 59 C) to Pen Branch have altered vegetation and deposited sediment in the Savannah River Swamp forming the Pen Branch delta. Currently, the delta covers over 300 acres and continues to expand at a rate of about 16 acres/yr. Examination of delta expansion can provide important information on environmental impacts to wetlands exposed to elevated temperature and flow conditions. To assess the current status and predict future expansion of the Pen Branch delta, historic aerial photographs were analyzed using both basic photo interpretation and computer techniques to provide the following information: (1) past and current expansion rates; (2) location and changes of impacted areas; (3) total acreage presently affected. Delta acreage changes were then compared to historic reactor discharge temperature and flow data to see if expansion rate variations could be related to reactor operations.

  15. The Collateral Consequences of Sex Offender Management Policies: Views From Professionals.

    PubMed

    Call, Corey

    2016-06-13

    In this study, the perceptions of community corrections professionals and clinical specialists toward the collateral consequences of current sex offender management policies were explored and contrasted. In addition, potential influencing factors of these perceptions were examined. Results indicate high levels of belief that sex offenders experience a variety of collateral consequences upon reentry; however, community corrections professionals are significantly less likely to believe that sex offenders experience collateral consequences than clinical specialists. Furthermore, few demographic variables were found to significantly influence the perceptions of the sample. Implications for the management of sex offenders are discussed.

  16. Radioiodinated branched carbohydrates

    DOEpatents

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1989-01-01

    A radioiodinated branched carbohydrate for tissue imaging. Iodine-123 is stabilized in the compound by attaching it to a vinyl functional group that is on the carbohydrate. The compound exhibits good uptake and retention and is promising in the development of radiopharmaceuticals for brain, heart and tumor imaging.

  17. Front Range Branch Officers

    NASA Astrophysics Data System (ADS)

    The Front Range Branch of AGU has installed officers for 1990: Ray Noble, National Center for Atmospheric Research, chair; Sherry Oaks, U.S. Geological Survey, chair-elect; Howard Garcia, NOAA, treasurer; Catharine Skokan, Colorado School of Mines, secretary. JoAnn Joselyn of NOAA is past chair. Members at large are Wallace Campbell, NOAA; William Neff, USGS; and Stephen Schneider, NCAR.

  18. Branching space-times

    NASA Astrophysics Data System (ADS)

    Placek, Tomasz; Müller, Thomas

    The five papers presented below have been selected from among the fourteen read at the European Science Foundation workshop Branching Space-Times (BST), held at the Jagiellonian University in Kraków, Poland, in October 2005. This event gathered for the first time leading researchers working on this subject.

  19. Spectrum of hepatofugal collateral pathways in portal hypertension: an illustrated radiological review.

    PubMed

    Arora, Ankur; Rajesh, S; Meenakshi, Yamini S; Sureka, Binit; Bansal, Kalpana; Sarin, Shiv Kumar

    2015-10-01

    The purpose of this article is to describe the various portosystemic collateral pathways pertinent to portal hypertension on multi-detector row computed tomography (MDCT) and their clinical relevance, with special emphasis on the uncommon ones. The knowledge and understanding of the various patterns of portosystemic collateral channels has important implications both for the clinician and the interventionist. MDCT with its advanced post processing capabilities can exquisitely demonstrate these vascular pathways to help in therapeutic decision making. Teaching points • Portosystemic collaterals are an important cause of bleeding and hepatic encephalopathy. • Radiologists should be familiar with the imaging findings to effectively identify them. • Pre-operative knowledge of portosystemic collaterals is essential to avoid inadvertent vascular injury.

  20. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency...

  1. 13 CFR 123.513 - Does SBA require collateral on its Military Reservist EIDL?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ADMINISTRATION DISASTER LOAN PROGRAM Military Reservist Economic Injury Disaster Loans § 123.513 Does SBA require... provide available collateral such as a lien on business property, a security interest in personal...

  2. Fatal derecruitment of occluded left anterior descending collaterals after left circumflex revascularization

    PubMed Central

    Boukhris, Marouane; Tomasello, Salvatore D.; Galassi, Alfredo R.

    2015-01-01

    Coronary arteries are not definitely functionally terminal arteries, as previously thought; indeed, they are linked and interconnected by a rich network of collaterals. Chronic total occlusions (CTOs) represent a subset of frequent lesions encountered in everyday catheterization laboratory practice, generally associated with a developed system of collateral connections. These latter have the capacity to prevent myocardial necrosis and may even uphold metabolic supply to the ischemic territory to maintain its contractile capacity. Authors have reported a rapid and progressive reduction of collateral function and their decline after antegrade flow restoration, resulting in higher myocardial susceptibility to ischemia in the CTO territory. Here, we report the case of a fatal derecruitment of collaterals for a left anterior descending CTO not reopened, after left circumflex subocclusion revascularization. PMID:26778906

  3. 7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... loan is reasonably assured when considered with the integrity and ability of project management... to the following: Land, buildings, machinery, equipment, furniture, fixtures, inventory, accounts receivable, cash or special cash collateral accounts, marketable securities and cash surrender value of...

  4. Resolution of bilateral moyamoya associated collateral vessel aneurysms: Rationale for endovascular versus surgical intervention

    PubMed Central

    Amin-Hanjani, Sepideh; Goodin, Sean; Charbel, Fady T.; Alaraj, Ali

    2014-01-01

    Background: Management of aneurysms associated with deep collateral vessels in moyamoya disease is challenging both from an endovascular and a surgical standpoint. Difficulties with access or localization, and compromise of the collateral circulation with subsequent ischemia are the primary concerns, making direct obliteration potentially unfeasible or risky. Alternatively, superficial temporal artery–middle cerebral artery bypass is another potential strategy for resolution of these aneurysms. Case Description: Presented are the findings and management for a patient with moyamoya disease and bilateral deep collateral vessel aneurysms, successfully treated with endovascular obliteration following a right-sided hemorrhage and subsequently with bypass for an unruptured but growing contralateral aneurysm. Conclusions: A rationale and approach to management is outlined, as derived from review of the current literature and the illustrative case with bilateral collateral vessel aneurysms. PMID:25071939

  5. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency...

  6. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency...

  7. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Ii-Open Policy War Risk Cargo Insurance § 308.522... use in establishing a collateral deposit fund, may be obtained from the American War Risk Agency...

  8. Incidentally detected right pulmonary artery agenesis with right coronary artery collateralization.

    PubMed

    Mikaberidze, Nino; Goldberg, Ythan; Khosraviani, Khashayar; Taub, Cynthia

    2014-01-01

    Unilateral pulmonary artery agenesis (UPAA) with pulmonary hypoplasia is a rare congenital anomaly. We describe a 71-year old male who was incidentally diagnosed with the right UPAA and a hypoplastic right lung supplied by collateralized right coronary.

  9. Isolated lateral collateral ligament complex injury in rock climbing and Brazilian Jiu-jitsu.

    PubMed

    Davis, Bryan A; Hiller, Lucas P; Imbesi, Steven G; Chang, Eric Y

    2015-08-01

    We report two occurrences of high-grade tears of the lateral collateral ligament complex (LCLC), consisting of the anterolateral ligament (ALL) and fibular collateral ligament (FCL). One injury occurred in a rock climber and the other in a martial artist. Increasing awareness of isolated injuries of the LCLC will allow for appropriate diagnosis and management. We review and discuss the anatomy of the LCLC, the unique mechanism of isolated injury, as well as physical and imaging examination findings.

  10. Cyclooxygenase blockade limits blood flow to collateral-dependent myocardium during exercise.

    PubMed

    Altman, J D; Klassen, C L; Bache, R J

    1995-11-01

    Cyclooxygenase blockade has been found to cause vasoconstriction of coronary collateral vessels in open-chest animals. This study was carried out to determine whether cyclooxygenase blockade can limit blood flow to collateral-dependent myocardium during exercise. Studies were performed in 8 adult mongrel dogs in which intermittent followed by permanent occlusion of the left anterior descending coronary artery produced an area of collateral-dependent myocardium. Myocardial blood flow was measured with radioactive microspheres at rest and during treadmill exercise to produce heart rates of 215 +/-0 7 beats/min. At rest collateral zone blood flow (1.00 +/- 0.10 ml/min per g) was significantly less than normal zone flow (1.23 +/- 0.14) (P < 0.05). During control exercise blood flow increased 91 +/- 22% in the collateral zone and 102 +/- 28% in the normal zone (each P < 0.05). Thirty minutes after cyclooxygenase blockade with indomethacin (5 mg/kg i.v.) blood flow in the normal zone and the collateral zone was not different from control during resting conditions. Indomethacin did not change heart rate or arterial pressure during exercise, but significantly increased the aortic-to-distal coronary pressure gradient from 33 +/- 3 to 40 +/- 5 mmHg (P < 0.05). Indomethacin increased transcollateral resistance during exercise by 42 +/- 10% (P < 0.05); this was associated with a 27 +/- 11% decrease in subendocardial flow in the collateral zone (P < 0.05) with no significant change in subepicardial flow, and no change in normal zone blood flow. These findings demonstrate that in the intact awake animal cyclooxygenase blockade causes coronary collateral vasoconstriction which can impair blood flow to the dependent myocardium during exercise.

  11. "One-stop" Hybrid approach for tetralogy of fallot with aortopulmonary collateral arteries in adults.

    PubMed

    Jiang, Yiyao; Zhang, Wei; Pei, Yu; Yang, Li; Xue, Langang; Liu, Xiaocheng

    2013-04-01

    We report a 45 year-old Chinese woman with tetralogy of fallot that had two aortopulmonary collateral arteries and tricuspid regurgitation. Collateral circulation was blocked and total correction was successfully performed in our "one-stop" hybrid operation room. The patient was weaned from cardiopulmonary bypass after 97 minutes and was transferred to the intensive care unit for about 36 hours. Without any complications, the patient was discharged home in the following eight days.

  12. [Approach to the road of vigorously developing Chinese medicine by scientific location of channels and collaterals].

    PubMed

    Li, Ding-zhong; Fu, Song-tao; Mi, He-yin; Li, Xiu-zhang; Zhang, Chang-lin; Zhang, Wei-bo

    2008-12-01

    Through researches of channels and collaterals and clinical practice of many years, the authors understand that Chinese medicine, which considers the human body as an interrelated, mutual constraints, whole, dynamic living system, has gradually become an important part of modern medicine. Channels and collaterals are a closed loop system which is communicated and linked by energy and information in the form of electromagnetic oscillation, reflecting many characteristics similar to quantum. Channels and collaterals are not a fixed organizational structure. Studies on channel and collaterals find that the track of the propagated sensation along channels (PSC) have the phenomenon drifting about. This exactly reflects the law of channels dynamically running. By information triggering and living resonance, channels and collaterals bring into play entirely regulative action. The innovative treatment of channels and collaterals followed by characteristics and laws of quantum can get a better curative effect. Theory of channels in the position of quantum information medical science provides an important breach for modernization of Chinese medicine.

  13. Cerebral collateral therapeutics in acute ischemic stroke: A randomized preclinical trial of four modulation strategies.

    PubMed

    Beretta, Simone; Versace, Alessandro; Carone, Davide; Riva, Matteo; Dell'Era, Valentina; Cuccione, Elisa; Cai, Ruiyao; Monza, Laura; Pirovano, Silvia; Padovano, Giada; Stiro, Fabio; Presotto, Luca; Paternò, Giovanni; Rossi, Emanuela; Giussani, Carlo; Sganzerla, Erik P; Ferrarese, Carlo

    2017-01-01

    Cerebral collaterals are dynamically recruited after arterial occlusion and highly affect tissue outcome in acute ischemic stroke. We investigated the efficacy and safety of four pathophysiologically distinct strategies for acute modulation of collateral flow (collateral therapeutics) in the rat stroke model of transient middle cerebral artery (MCA) occlusion. A composed randomization design was used to assign rats (n = 118) to receive phenylephrine (induced hypertension), polygeline (intravascular volume load), acetazolamide (cerebral arteriolar vasodilation), head down tilt (HDT) 15° (cerebral blood flow diversion), or no treatment, starting 30 min after MCA occlusion. Compared to untreated animals, treatment with collateral therapeutics was associated with lower infarct volumes (62% relative mean difference; 51.57 mm(3) absolute mean difference; p < 0.001) and higher chance of good functional outcome (OR 4.58, p < 0.001). Collateral therapeutics acutely increased cerebral perfusion in the medial (+40.8%; p < 0.001) and lateral (+19.2%; p = 0.016) MCA territory compared to pretreatment during MCA occlusion. Safety indicators were treatment-related mortality and cardiorespiratory effects. The highest efficacy and safety profile was observed for HDT. Our findings suggest that acute modulation of cerebral collaterals is feasible and provides a tissue-saving effect in the hyperacute phase of ischemic stroke prior to recanalization therapy.

  14. Acute development of collateral circulation and therapeutic prospects in ischemic stroke.

    PubMed

    Iwasawa, Eri; Ichijo, Masahiko; Ishibashi, Satoru; Yokota, Takanori

    2016-03-01

    In acute ischemic stroke, collateral circulation plays an important role in maintaining blood flow to the tissue that is at risk of progressing into ischemia, and in increasing the successful recanalization rate without hemorrhagic transformation. We have reported that well-developed collateral circulation is associated with smaller infarct volume and better long-term neurological outcome, and it disappears promptly once the effective recanalization is achieved. Contrary to the belief that collateral vessels develop over time in chronic stenotic condition, there exists a phenomenon that collateral circulation develops immediately in acute stenosis or occlusion of the arteries and it seems to be triggered by fluid shear stress, which occurs between the territories of stenotic/occluded arteries and those fed by surrounding intact arteries. We believe that this acute development of collateral circulation is a target of novel therapeutics in ischemic stroke and refer our recent attempt in enhancing collateral circulation by modulating sphingosine-1-phosphate receptor 1, which is a known shear-stress mechanosensing protein.

  15. Direct Cortical Inputs Erase LTP at Schaffer Collateral Synapses

    PubMed Central

    Izumi, Yukitoshi; Zorumski, Charles F.

    2008-01-01

    Long-term potentiation (LTP), a synaptic mechanism thought to underlie memory formation, has been studied extensively at hippocampal Schaffer collateral (SC) synapses. The SC pathway transmits information to area CA1 that originates in entorhinal cortex and is processed by the dentate gyrus and area CA3. CA1 also receives direct excitatory input from entorhinal cortex via the perforant path (PP), but the role of this cortical input is less certain. Here we report that low frequency stimulation of PP inputs to CA1 has no lasting effect on basal SC transmission, but effectively depotentiates SC synapses that have undergone LTP in a fashion that can be reversed by subsequent high frequency stimulation of SC inputs. This depotentiation does not require N-methyl-D-aspartate receptors, Group I metabotropic glutamate receptors or L-type calcium channels, but involves adenosine acting at A1 receptors. Given the limited storage capacity of the hippocampus, these observations provide a mechanism by which input from cortex can help to reset synaptic transmission in the hippocampus and facilitate further information processing. PMID:18799687

  16. Collateral pathways from the ventromedial hypothalamus mediate defensive behaviors

    PubMed Central

    Wang, Li; Chen, Irene Z.; Lin, Dayu

    2014-01-01

    Summary The ventromedial hypothalamus (VMH) was thought to be essential for coping with threat, although its circuit mechanism remains unclear. To investigate this, we optogenetically activated steroidogenic factor 1 (SF1)-expressing neurons in the dorsomedial and central part of VMH (VMHdm/c), and observed a range of context dependent somatomotor and autonomic responses resembling animals' natural defensive behaviors. By activating independent pathways emanating from VMHdm/c, we demonstrated that VMHdm/c projection to the dorsolateral periaqueductal gray (dlPAG) induces inflexible immobility, while the VMHdm/c to anterior hypothalamic nucleus (AHN) pathway promotes avoidance. Furthermore, consistent with the behavior changes induced by VMH to AHN pathway activation, direct activation of the AHN elicited avoidance and escape jumping but not immobility. Finally, retrograde tracing studies revealed that nearly 50% of PAG- projecting VMHdm/c neurons send collateral projection to the AHN and vice versa. Thus, VMHdm/c neurons employ a one-to-many wiring configuration to orchestrate multiple aspects of defensive behaviors. PMID:25754823

  17. Targeting pathogen metabolism without collateral damage to the host

    PubMed Central

    Haanstra, Jurgen R.; Gerding, Albert; Dolga, Amalia M.; Sorgdrager, Freek J. H.; Buist-Homan, Manon; du Toit, François; Faber, Klaas Nico; Holzhütter, Hermann-Georg; Szöör, Balázs; Matthews, Keith R.; Snoep, Jacky L.; Westerhoff, Hans V.; Bakker, Barbara M.

    2017-01-01

    The development of drugs that can inactivate disease-causing cells (e.g. cancer cells or parasites) without causing collateral damage to healthy or to host cells is complicated by the fact that many proteins are very similar between organisms. Nevertheless, due to subtle, quantitative differences between the biochemical reaction networks of target cell and host, a drug can limit the flux of the same essential process in one organism more than in another. We identified precise criteria for this ‘network-based’ drug selectivity, which can serve as an alternative or additive to structural differences. We combined computational and experimental approaches to compare energy metabolism in the causative agent of sleeping sickness, Trypanosoma brucei, with that of human erythrocytes, and identified glucose transport and glyceraldehyde-3-phosphate dehydrogenase as the most selective antiparasitic targets. Computational predictions were validated experimentally in a novel parasite-erythrocytes co-culture system. Glucose-transport inhibitors killed trypanosomes without killing erythrocytes, neurons or liver cells. PMID:28084422

  18. Model of spatio-temporal propagation of action potentials in the Schaffer collateral pathway of the CA1 area of the rat hippocampus.

    PubMed

    Bernard, C; Cannon, R C; Ben Ari, Y; Wheal, H V

    1997-01-01

    There is a sharp contrast between the profuse in vivo axonal arborization of CA3 pyramidal cells in the CA1 area and the low probability of finding pairs of connected CA3-CA1 pyramidal cells in vitro. These anatomical differences contribute to a connectivity argument for discrepancies between electrophysiological data recorded in vitro and in vivo. In order to investigate this issue, we have developed a realistic computer model of the Schaffer collateral pathway of the hippocampus and analyzed the spatio-temporal distribution of action potentials along this pathway following three different types of electrical test stimulus. Direct activation of mossy fibers, CA3 pyramidal cells and focal stimulation of CA1 stratum radiatum were investigated. The parameters of the model were selected from available biological data. Spikes in Schaffer collaterals were followed from their onset in the CA3 pyramidal cell initial segment to the last order branches of their axonal tree in two types of configuration: the whole hippocampus and the slice configuration. The anatomical and electropysiological characteristics of the mossy fibre and Schaffer collateral pathways were found to impose strong constraints on the spatio-temporal distribution of action potentials in the CA1 area. Specific projection zones are determined by the spatial localization of the emitting CA3 pyramidal cells. Their position also defines precise time windows during which some CA1 projection zones receive a large number of correlated signals. Moreover, the variability of the delay at the mossy fibre/CA3 pyramidal cell synapse seems to provide the CA1 projection zones with a background level of excitation. Finally, we show how the patterns of activation obtained in the whole hippocampus are different from those obtained in the slice.

  19. Branching structure and strain hardening of branched metallocene polyethylenes

    SciTech Connect

    Torres, Enrique; Li, Si-Wan; Costeux, Stéphane; Dealy, John M.

    2015-09-15

    There have been a number of studies of a series of branched metallocene polyethylenes (BMPs) made in a solution, continuous stirred tank reactor (CSTR) polymerization. The materials studied vary in branching level in a systematic way, and the most highly branched members of the series exhibit mild strain hardening. An outstanding question is which types of branched molecules are responsible for strain hardening in extension. This question is explored here by use of polymerization and rheological models along with new data on the extensional flow behavior of the most highly branched members of the set. After reviewing all that is known about the effects of various branching structures in homogeneous polymers and comparing this with the structures predicted to be present in BMPs, it is concluded that in spite of their very low concentration, treelike molecules with branch-on-branch structure provide a large number of deeply buried inner segments that are essential for strain hardening in these polymers.

  20. Libraries across Land and Sea: Academic Library Services on International Branch Campuses

    ERIC Educational Resources Information Center

    Green, Harriett

    2013-01-01

    This preliminary study explores how library services are offered at the international branch campuses of U.S. institutions of higher education, including librarians' experiences, challenges faced, and collaborations with the home U.S. institutions. The data from a Web survey distributed to international branch campus librarians, a conducted…

  1. Thermal Energy Conversion Branch

    NASA Technical Reports Server (NTRS)

    Bielozer, Matthew C.; Schreiber, Jeffrey, G.; Wilson, Scott D.

    2004-01-01

    The Thermal Energy Conversion Branch (5490) leads the way in designing, conducting, and implementing research for the newest thermal systems used in space applications at the NASA Glenn Research Center. Specifically some of the most advanced technologies developed in this branch can be broken down into four main areas: Dynamic Power Systems, Primary Solar Concentrators, Secondary Solar Concentrators, and Thermal Management. Work was performed in the Dynamic Power Systems area, specifically the Stirling Engine subdivision. Today, the main focus of the 5490 branch is free-piston Stirling cycle converters, Brayton cycle nuclear reactors, and heat rejection systems for long duration mission spacecraft. All space exploring devices need electricity to operate. In most space applications, heat energy from radioisotopes is converted to electrical power. The Radioisotope Thermoelectric Generator (RTG) already supplies electricity for missions such as the Cassini Spacecraft. The focus of today's Stirling research at GRC is aimed at creating an engine that can replace the RTG. The primary appeal of the Stirling engine is its high system efficiency. Because it is so efficient, the Stirling engine will significantly reduce the plutonium fuel mission requirements compared to the RTG. Stirling is also being considered for missions such as the lunar/Mars bases and rovers. This project has focused largely on Stirling Engines of all types, particularly the fluidyne liquid piston engine. The fluidyne was developed by Colin D. West. This engine uses the same concepts found in any type of Stirling engine, with the exception of missing mechanical components. All the working components are fluid. One goal was to develop and demonstrate a working Stirling Fluidyne Engine at the 2nd Annual International Energy Conversion Engineering Conference in Providence, Rhode Island.

  2. Combustion Branch Website Development

    NASA Technical Reports Server (NTRS)

    Bishop, Eric

    2004-01-01

    The NASA combustion branch is a leader in developing and applying combustion science to focused aerospace propulsion systems concepts. It is widely recognized for unique facilities, analytical tools, and personnel. In order to better communicate the outstanding research being done in this Branch to the public and other research organization, a more substantial website was desired. The objective of this project was to build an up-to-date site that reflects current research in a usable and attractive manner. In order to accomplish this, information was requested from all researchers in the Combustion branch, on their professional skills and on the current projects. This information was used to fill in the Personnel and Research sections of the website. A digital camera was used to photograph all personnel and these photographs were included in the personnel section as well. The design of the site was implemented using the latest web standards: xhtml and external css stylesheets. This implementation conforms to the guidelines recommended by the w3c. It also helps to ensure that the web site is accessible by disabled users, and complies with Section 508 Federal legislation (which mandates that all Federal websites be accessible). Graphics for the new site were generated using the gimp (www.gimp.org) an open-source graphics program similar to Adobe Photoshop. Also, all graphics on the site were of a reasonable size (less than 20k, most less than 2k) so that the page would load quickly. Technologies such as Macromedia Flash and Javascript were avoided, as these only function on some clients which have the proper software installed or enabled. The website was tested on different platforms with many different browsers to ensure there were no compatibility issues. The website was tested on windows with MS IE 6, MSIE 5 , Netscape 7, Mozilla and Opera. On a Mac, the site was tested with MS IE 5 , Netscape 7 and Safari.

  3. Interrogating the functional correlates of collateralization in patients with intracranial stenosis using multi-modal hemodynamic imaging

    PubMed Central

    Roach, Brent A.; Donahue, Manus J.; Davis, L. Taylor; Faraco, Carlos C.; Arteaga, Daniel; Chen, Sheau-Chiann; Ladner, Travis; Scott, Allison O.; Strother, Megan K.

    2016-01-01

    Background and Purpose The importance of collateralization for maintaining adequate cerebral perfusion is increasingly recognized. However, measuring collateral flow noninvasively has proved elusive. The aim of this study was to assess correlations among (1) baseline perfusion and arterial transit time artifact, (2) cerebrovascular reactivity (CVR), and (3) the presence of collateral vessels on digital subtraction angiography (DSA). Materials and Methods The relationship between the presence of collateral vessels on arterial-spin-labeling (ASL) MRI and DSA was compared to blood-oxygenation-level-dependent (BOLD) MRI measures of hypercapnic cerebrovascular reactivity (CVR) in patients with symptomatic intracranial stenosis (n=18). DSA maps were reviewed by a neuroradiologist and assigned the following scores: 1) collaterals to the periphery of the ischemic site; 2) complete irrigation of the ischemic bed via collateral flow; 3) normal antegrade flow. ASL maps were scored according to 0) low signal; 1) moderate signal with arterial transit artifact (ATA); 2) high signal with ATA; 3) normal signal. Results In regions with normal-to-high signal on ASL, collateral vessel presence on DSA strongly correlated with declines in CVR as measured on BOLD MRI (p<0.001), most notably in patients with non-atherosclerotic disease. There was a trend toward increasing CVR with increases in the degree of collateralization on DSA (p=0.082). Conclusion Collateral vessels may have fundamentally different vasoreactivity properties than healthy vessels, a finding that is observed most prominently in non-atherosclerotic disease and to a lesser extent in atherosclerotic disease. PMID:27056428

  4. Collateral circulation from the conus coronary artery to the anterior descending coronary artery: assessment using multislice coronary computed tomography.

    PubMed

    de Agustín, José A; Marcos-Alberca, Pedro; Hernández-Antolín, Rosana; Vilacosta, Isidre; Pérez de Isla, Leopoldo; Rodríguez, Enrique; Macaya, Carlos; Zamorano, José

    2010-03-01

    The prognosis of patients with coronary artery disease largely depends on the presence of a collateral circulation. The location and extent of the collateral circulation is highly variable and these parameters determine whether or not ischemic symptoms occur and whether left ventricular contractility is abnormal. The collateral circulation is generally established through small-caliber distal vessels, although many different forms have been described. We report on three patients with severe left coronary artery disease and collateral circulation through a large conus coronary artery that joined a proximal or medial segment of the left anterior descending coronary artery. In all three cases, left ventricular function was preserved.

  5. Flight Dynamics Analysis Branch

    NASA Technical Reports Server (NTRS)

    Stengle, Tom; Flores-Amaya, Felipe

    2000-01-01

    This report summarizes the major activities and accomplishments carried out by the Flight Dynamics Analysis Branch (FDAB), Code 572, in support of flight projects and technology development initiatives in fiscal year 2000. The report is intended to serve as a summary of the type of support carried out by the FDAB, as well as a concise reference of key accomplishments and mission experience derived from the various mission support roles. The primary focus of the FDAB is to provide expertise in the disciplines of flight dynamics, spacecraft trajectory, attitude analysis, and attitude determination and control. The FDAB currently provides support for missions and technology development projects involving NASA, government, university, and private industry.

  6. Giant aorto-pulmonary collaterals in pulmonary atresia and ventricular septal defect: long-term survival in unoperated adults.

    PubMed

    Spaziani, Gaia; Favilli, Silvia; Fonda, Claudio; Chiappa, Enrico

    2013-08-01

    The association of pulmonary atresia and ventricular septal defect (PA/VSD) can be considered the most severe form of tetralogy of Fallot. The main feature of this congenital heart disease is represented by discontinuity between the right ventricle and pulmonary trunk or its branches; the anatomy of central pulmonary arteries is often abnormal, consequently the type and the amount of sources of pulmonary blood flow are variable. Due to evolution in surgical techniques, definitive correction is now also considered in more complex cases. A small rate of unoperated patients with PA/VSD can survive until adulthood and the arterial blood supply to the lungs, provided by major aorto-pulmonary collateral arteries (MAPCAs), is one of the main determinants of survival. We report two unoperated cases of PA/VSD and MAPCAs with long-term survival. Giant MAPCAs can occasionally be found by chest radiography in adults with unrepaired PA/VSD. Moreover, non-invasive assessment of the pulmonary arterial bed with computer tomography or MRI is helpful in these patients during follow-up. Finally, we discuss the use of oral anticoagulants and/or 5-phosphodiesterase inhibitors in these patients.

  7. Strigolactone inhibition of shoot branching.

    PubMed

    Gomez-Roldan, Victoria; Fermas, Soraya; Brewer, Philip B; Puech-Pagès, Virginie; Dun, Elizabeth A; Pillot, Jean-Paul; Letisse, Fabien; Matusova, Radoslava; Danoun, Saida; Portais, Jean-Charles; Bouwmeester, Harro; Bécard, Guillaume; Beveridge, Christine A; Rameau, Catherine; Rochange, Soizic F

    2008-09-11

    A carotenoid-derived hormonal signal that inhibits shoot branching in plants has long escaped identification. Strigolactones are compounds thought to be derived from carotenoids and are known to trigger the germination of parasitic plant seeds and stimulate symbiotic fungi. Here we present evidence that carotenoid cleavage dioxygenase 8 shoot branching mutants of pea are strigolactone deficient and that strigolactone application restores the wild-type branching phenotype to ccd8 mutants. Moreover, we show that other branching mutants previously characterized as lacking a response to the branching inhibition signal also lack strigolactone response, and are not deficient in strigolactones. These responses are conserved in Arabidopsis. In agreement with the expected properties of the hormonal signal, exogenous strigolactone can be transported in shoots and act at low concentrations. We suggest that endogenous strigolactones or related compounds inhibit shoot branching in plants. Furthermore, ccd8 mutants demonstrate the diverse effects of strigolactones in shoot branching, mycorrhizal symbiosis and parasitic weed interaction.

  8. Embolization of Collateral Vessels Using Mechanically Detachable Coils in Young Children with Congenital Heart Disease

    SciTech Connect

    Sato, Y.; Ogino, H.; Hara, M.; Satake, M.; Oshima, H.; Banno, T.; Mizuno, K.; Mishima, A.; Shibamoto, Y.

    2003-11-15

    Our objective was to evaluate the usefulness of embolizing collateral vessels using mechanically detachable coils (MDCs) in children aged 3 years or younger with congenital heart disease. The subjects were 8 children with congenital heart disease featuring collateral vessels (age 18 days-3 years): 3 with a single ventricle, 2 with the tetralogy of Fallot, 2 with pulmonary atresia, and 1 with a ventricular septal defect. The embolized vessels were the major aortopulmonary collateral artery (MAPCA) in 5 patients, the persistent left superior vena cava in 2, and the coronary arteriovenous fistula in 1. A 4 or a 5 F catheter was used as the guiding device, and embolization was performed using MDCs and other conventional coils introduced through the microcatheter. One patient had growth of new MAPCAs after embolization, and these MAPCAs were also embolized with MDCs. Thus, a total of 9 embolization procedures were performed in 8 patients. Complete occlusion of the collateral vessels was achieved in 8 of 9 procedures (89%). Seven of 8 patients (88%) had uneventful courses after embolization, and MDC procedures appeared to play important roles in avoiding coil migration and achievement of safe coil embolization. One patient who underwent MAPCA embolization showed no improvement in heart function and died 2 months and 19 days later. Embolization of collateral vessels using MDCs in young children with congenital heart disease can be an effective procedure and a valuable adjunct to surgical management.

  9. Trans-illuminated laser speckle imaging of collateral artery blood flow in ischemic mouse hindlimb.

    PubMed

    Meisner, Joshua K; Niu, Jacqueline; Sumer, Suna; Price, Richard J

    2013-09-01

    The mouse ischemic hindlimb model is used widely for studying collateral artery growth (i.e., arteriogenesis) in response to increased shear stress. Nonetheless, precise measurements of regional shear stress changes along individual collateral arteries are lacking. Our goal is to develop and verify trans-illumination laser speckle flowmetry (LSF) for this purpose. Studies of defibrinated bovine blood flow through tubes embedded in tissue-mimicking phantoms indicate that trans-illumination LSF better maintains sensitivity with an increasing tissue depth when compared to epi-illumination, with an ∼50% reduction in the exponential decay of the speckle velocity signal. Applying trans-illuminated LSF to the gracilis muscle collateral artery network in vivo yields both improved sensitivity and reduced noise when compared to epi-illumination. Trans-illuminated LSF images reveal regional differences in collateral artery blood velocity after femoral artery ligation and are used to measure an ∼2-fold increase in the shear stress at the entrance regions to the muscle. We believe these represent the first direct measurements of regional shear stress changes in individual mouse collateral arteries. The ability to capture deeper vascular signals using a trans-illumination configuration for LSF may expand the current applications for LSF, which could have bearing on determining how shear stress magnitude and direction regulate arteriogenesis.

  10. Increased circulating monocyte count is related to good collateral development in coronary artery disease.

    PubMed

    Kocaman, Sinan Altan; Arslan, Uğur; Tavil, Yusuf; Okuyan, Hizir; Abaci, Adnan; Cengel, Atiye

    2008-04-01

    Monocytes have been shown to take an important role in collateral growth in animal studies. The aim of the study was to investigate the relation of circulating monocyte count with collateral development in patients with severely stenotic CAD. Patients who had > or =95% stenosis in at least one major coronary artery were included in the study. Coronary angiograms of 210 eligible patients from our database were analyzed again and 103 of them had good and 107 had poor collateral development according to Cohen-Rentrop method. Only the monocyte count was found to be significantly different between two groups (671+/-218 mm(-3) versus 522+/-195 mm(-3), p<0.001) when multivariate analysis was performed and an increased monocyte count was observed in the good collateral group (Odds ration [OR], 2.918; 95% confidence interval [CI], 1.281-6.648, p=0.011). This study in which the relationship between monocyte count in blood and collateral development was disclosed has a potential importance in clinical and basic cardiovascular medicine.

  11. Self-, collateral- and clinician assessment of depression in persons with cognitive impairment

    PubMed Central

    Chopra, Mohit P.; Sullivan, Jan R.; Feldman, Zachary; Landes, Reid D.; Beck, Cornelia

    2011-01-01

    Objectives This investigation examined the associations between self-reports, collateral-source reports and a clinician’s diagnosis of depression in persons with cognitive impairment. Method Responses on the Geriatric Depression Scale – 15 (GDS-15) from 162 participants with a diagnosis of Mild Cognitive Impairment (n = 78) or Alzheimer’s Dementia and a Mini-Mental State score ≥15 (n = 84) were compared with both their collateral sources’ report on either the Neuropsychiatric Inventory Questionnaire (n = 93) and/or the collateral-source GDS-15 (n = 67), or a clinician’s diagnosis of Major Depression (MD). Results Significant differences were seen between self- versus collateral-source reports of depression in these participants. Participants’ reports of loss of interest (anhedonia) significantly increased the odds of disagreement with their collateral sources (OR = 3.78, 95% CI: 1.3–11.2) while reports of negative cognitions significantly decreased the odds of such a disagreement (OR = 0.31, 95% CI: 0.1–0.9). The symptom of anhedonia also showed the strongest association with the clinician’s diagnosis of MD. Conclusion A motivational symptom like loss of interest was seen to play an important role in depression experienced by those with cognitive impairment. PMID:19023719

  12. Biomechanics of a less invasive procedure for reconstruction of the ulnar collateral ligament of the elbow.

    PubMed

    Hechtman, K S; Tjin-A-Tsoi, E W; Zvijac, J E; Uribe, J W; Latta, L L

    1998-01-01

    A reconstruction of the anterior bundle of the ulnar collateral ligament of the elbow using bone anchors was compared regarding strain and valgus load strength with the intact ulnar collateral ligament and the reconstructed ulnar collateral ligament using bone tunnels. In both normal and reconstructed elbows, the anterior band and posterior band were tight during only a portion of the range of motion. Toward extension, the mean peak strain in the anterior band was tight for the normal and bone anchor groups, but lax in the bone tunnel group. Toward extension, the mean peak strain in the posterior band was lax in all elbows. Toward flexion, the strain in the anterior band was lax in the normal and bone anchor groups, but tight in the bone tunnel group. The mean of the peak strains for the posterior band toward flexion was tight for all elbows. Mean valgus load strength of normal elbows was 22.7 +/- 9.0 N.m. The bone tunnel and bone anchor mean strengths were 76.3% and 63.5%, respectively, of normal elbow strength. We concluded that the bone anchor reproduced the normal anatomy and mechanical function of the ulnar collateral ligament more closely than the bone tunnel, and that both reconstruction methods were significantly weaker than the normal ulnar collateral ligament. However, we found no significant difference in reconstruction strength between bone anchor and bone tunnel.

  13. Branching toughens fibrous networks.

    PubMed

    Koh, C T; Oyen, M L

    2012-08-01

    Fibrous collagenous networks are not only stiff but also tough, due to their complex microstructures. This stiff yet tough behavior is desirable for both medical and military applications but it is difficult to reproduce in engineering materials. While the nonlinear hyperelastic behavior of fibrous networks has been extensively studied, the understanding of toughness is still incomplete. Here, we identify a microstructure mimicking the branched bundles of a natural type I collagen network, in which partially cross-linked long fibers give rise to novel combinations of stiffness and toughness. Finite element analysis shows that the stiffness of fully cross-linked fibrous networks is amplified by increasing the fibril length and cross-link density. However, a trade-off of such stiff networks is reduced toughness. By having partially cross-linked networks with long fibrils, the networks have comparable stiffness and improved toughness as compared to the fully cross-linked networks. Further, the partially cross-linked networks avoid the formation of kinks, which cause fibril rupture during deformation. As a result, the branching allows the networks to have stiff yet tough behavior.

  14. Treatment of Ulnar Collateral Ligament Tears of the Elbow

    PubMed Central

    Erickson, Brandon J.; Bach, Bernard R.; Verma, Nikhil N.; Bush-Joseph, Charles A.; Romeo, Anthony A.

    2017-01-01

    Background: Ulnar collateral ligament (UCL) tears have become common, and UCL reconstruction (UCLR) is currently the preferred surgical treatment method for treating UCL tears. Purpose/Hypothesis: The purpose of this study was to review the literature surrounding UCL repair and determine the viability of new repair techniques for treatment of UCL tears. We hypothesized that UCL repair techniques will provide comparable results to UCLR for treatment of UCL tears. Study Design: Systematic review and meta-analysis; Level of evidence, 4. Methods: A systematic review was registered with PROSPERO and performed with PRISMA guidelines using 3 publicly available free databases. Biomechanical and clinical outcome investigations reporting on UCL repair with levels of evidence 1 through 4 were eligible for inclusion. Descriptive statistics were calculated for each study and parameter/variable analyzed. Results: Of the 46 studies eligible, 4 studies (3 clinical and 1 biomechanical) were included. There were 92 patients (n = 92 elbows; 61 males [62.3%]; mean age, 21.9 ± 4.7 years) included in the clinical studies, with a mean follow-up of 49 ± 14.4 months. Eighty-six percent of repairs performed were on the dominant elbow, and 38% were in college athletes. Most UCL repairs (66.3%) were performed via suture anchors. After UCL repair, 87.0% of patients were able to return to sport. Overall, 94.9% of patients scored excellent/good on the Andrews-Carson score. Patients who were able to return to sport after UCL repair did so within 6 months after surgery. Biomechanically, when UCL repair was compared with the modified Jobe technique, the repair group showed significantly less gap formation than the reconstruction group. Conclusion: In patients for whom repair is properly indicated, UCL repair provides similar return-to-sport rates and clinical outcomes with shorter return-to-sport timing after repair compared with UCL reconstruction. Future outcome studies evaluating UCL repair

  15. Synthesis of branched polysaccharides with tunable degree of branching.

    PubMed

    Ciric, Jelena; Loos, Katja

    2013-03-01

    An in vitro enzyme-catalyzed tandem reaction using the enzymes phosphorylase b from rabbit muscle and Deinococcus geothermalis glycogen branching enzyme (Dg GBE) to obtain branched polyglucans with tunable degree of branching (2% ÷ 13%) is presented. The tunable degree of branching is obtained by varying the reaction conditions such as pH value, the choice of reducing agent and its concentration and reaction time. Linear amylose is formed by the phosphorylase-catalyzed propagation of glucose-1-phosphate while Dg GBE introduces branching points on the α-(1→6) position by relocating short oligosaccharide chains. Our results show that the best way to obtain different degrees of branching with this set of enzymes is by regulation of the reaction time.

  16. [Original relations of acupoints with channels-collaterals and acupuncture therapy].

    PubMed

    Bai, Xing-hua

    2008-03-01

    With analysis and systematization of ancient medical books being unearthed Mazoangdui tomb and other literatures, it is found that ancient names and meanings of moxibustion and acupuncture parts passed the courses from Mai to Maikou, the place and region above Mai, then to acupoints on the body surface showing channels, gi and blood. This change trace reveals original relationship acupoints with channels-collaterals, and acupuncture therapy. The acupoint is a point and channels-collaterals are lines, except a less acupoints which located by obvious anatomic markers, most of are special parts on the channels and collaterals, are not a isolated point. The acupoint is the gate of needle inserting the human body, proposal of this concept and increase of the number of acopoints are closely related with invention, popularity and spreading of acupuncture therapy.

  17. Indocyanine Green Lymphographic Signs of Lymphatic Collateral Formation in Lower Extremity Lymphedema After Cancer Resection.

    PubMed

    Tashiro, Kensuke; Shibata, Takashi; Mito, Daisuke; Ishiura, Ryohei; Kato, Motoi; Yamashita, Shuji; Narushima, Mitsunaga; Iida, Takuya; Koshima, Isao

    2016-08-01

    Indocyanine green lymphography has recently been used to assess lymphatic vessel function in lymphedema patients. Postoperative collateral lymphatic vessels toward ipsilateral axillary lymph nodes are rarely seen above the umbilical level in lower lymphedema patients. Between January 2012 and December 2014, we performed indocyanine green lymphography of 192 limbs in 96 lower extremity lymphedema cases. As a result, dermal back flow appeared in 95 cases, with 38 in the lower abdominal area and 31 in the genital area. We confirmed 3 cases of superficial lymphatic collateral ways extending above the umbilical level to the axillary lymph nodes. All 3 cases had similarity in lower abdominal edema, so excessive lymphatic fluid in the lower abdomen was assumed to be the cause. Lymphatic collateral ways from abdomen to axillary lymph nodes in this study was likely to be designed to prevent the progress of lymphedema.

  18. Comparing main and collateral effects of extinction and differential reinforcement of alternative behavior.

    PubMed

    Petscher, Erin Seligson; Bailey, Jon S

    2008-07-01

    This study evaluated the effects and collateral effects of extinction (EXT) and differential reinforcement of alternative behavior (DRA) interventions with inappropriate vocalizations and work refusal. Both interventions have been used frequently to reduce problem behaviors. The benefits of these interventions have been established yet may be outweighed by the reported negative side effects that result. However, these collateral effects have rarely been measured or reported. DRA produced the most rapid reductions in behavior for 4 of the 5 participants. Other behaviors were measured for changes and showed that the desirable collateral effect of academic engagement tended to be higher during EXT than DRA. No evidence of EXT bursts was present with any participant, although EXT-induced aggression occurred with 1 participant.

  19. Genetic lineage tracing discloses arteriogenesis as the main mechanism for collateral growth in the mouse heart

    PubMed Central

    He, Lingjuan; Liu, Qiaozhen; Hu, Tianyuan; Huang, Xiuzhen; Zhang, Hui; Tian, Xueying; Yan, Yan; Wang, Li; Huang, Yu; Miquerol, Lucile; Wythe, Joshua D.; Zhou, Bin

    2016-01-01

    Aims Capillary and arterial endothelial cells share many common molecular markers in both the neonatal and adult hearts. Herein, we aim to establish a genetic tool that distinguishes these two types of vessels in order to determine the cellular mechanism underlying collateral artery formation. Methods and results Using Apln-GFP and Apln-LacZ reporter mice, we demonstrate that APLN expression is enriched in coronary vascular endothelial cells. However, APLN expression is reduced in coronary arterial endothelial cells. Genetic lineage tracing, using an Apln-CreER mouse line, robustly labelled capillary endothelial cells, but not arterial endothelial cells. We leveraged this differential activity of Apln-CreER to study collateral artery formation following myocardial infarction (MI). In a neonatal heart MI model, we found that Apln-CreER-labelled capillary endothelial cells do not contribute to the large collateral arteries. Instead, these large collateral arteries mainly arise from pre-existing, infrequently labelled coronary arteries, indicative of arteriogenesis. Furthermore, in an adult heart MI model, Apln-CreER activity also distinguishes large and small diameter arteries from capillaries. Lineage tracing in this setting demonstrated that most large and small coronary arteries in the infarcted myocardium and border region are derived not from capillaries, but from pre-existing arteries. Conclusion Apln-CreER-mediated lineage tracing distinguishes capillaries from large arteries, in both the neonatal and adult hearts. Through genetic fate mapping, we demonstrate that pre-existing arteries, but not capillaries, extensively contribute to collateral artery formation following myocardial injury. These results suggest that arteriogenesis is the major mechanism underlying collateral vessel formation. PMID:26768261

  20. Ligation of the left hepatic vein for dilated intrahepatic collaterals late after fontan operation.

    PubMed

    Park, Chun Soo; Park, Jeong-Jun; Park, In-Sook; Goo, Hyun Woo

    2014-07-01

    A 17-year-old male presented with two episodes of syncope, cyanosis, and exercise intolerance 13 years after the Fontan operation. Echocardiography and magnetic resonance imaging showed dilated intrahepatic collaterals, which drained into the atrium through the left hepatic vein, and 24-hour Holter monitoring revealed sinus node dysfunction. We performed ligation of the left hepatic vein using intrahepatic collaterals as channels draining hepatic venous blood into the Fontan pathway, and implanted an epicardial dual chamber pacemaker. At one-year follow-up, the patient remained asymptomatic and his cardiac performance was much improved.

  1. Investigation of water spray to reduce collateral thermal damage during laser resection of soft tissue

    NASA Astrophysics Data System (ADS)

    Theisen-Kunde, D.; Wolken, H.; Ellebrecht, D.; Danicke, V.; Wurster, L.; Kleemann, M.; Birngruber, R.

    2013-06-01

    To reduce unwanted collateral thermal damage to surrounding tissue and organs during laparoscopic laser dissection (cw, wavelength: 1.9μm) of porcine liver water spray was used. Size and amount of the produced water droplets of the water spray were photographed by short time imaging and analyzed by imaging software. At in vivo measurements on fresh porcine liver the depth of thermal damage was reduced by 85 % with water spray and the lateral size of thermal damage at the tissue surface could be reduced by 67%. This results show that especially for laparoscopic laser surgery water spray application might be a useful tool to avoid unwanted collateral thermal damage.

  2. Who died? The murder of collaterals related to intimate partner conflict.

    PubMed

    Dobash, Russell P; Dobash, R Emerson

    2012-06-01

    Using data from the Murder in Britain Study, the authors focus on murders that are related to intimate partner conflict but involve the killing of a person other than the intimate partner. Intimate partner collateral murders (IPCM) include children, allies, and new partners. The findings expand the number and types of murder associated with intimate partner conflict, characterize the three main types of collaterals, compare the childhood and adulthood of the perpetrators of intimate partner murder [IPM] (n = 104) and IPCM (n = 62), and reflect similarities and differences. Various disciplinary approaches are reflected in the research design, data collection, findings, and conclusions.

  3. Transhepatic Venous Approach for Balloon-assisted Cervical Collateral Venous Access

    SciTech Connect

    Eyheremendy, Eduardo P.; Malizia, Patricio; Sierre, Sergio

    2011-12-15

    Central venous catheter placement is indicated in many situations, and an increasing number of patients require temporary and long-term central catheters. Frequently, patients who have undergone multiple central veins catheterizations develop complete and diffuse venous occlusion, and this constitutes a difficult-to-manage clinical problem. We report a case of a 20-year-old patient who was referred to our department for central venous line placement who manifested bilateral femoral, jugular, and subclavian veins occlusion. A central venous catheter was implanted through a cervical collateral vein, targeting on and puncturing an angioplasty balloon, and advanced into the collateral vein through a transhepatic venous access.

  4. [Destruction of residual varicose collaterals by subcutaneous dilaceration with a needle].

    PubMed

    Lengua, F; Pajot, A; Buffet, J M; Kassem, S; Fernandez, R

    1980-01-01

    The persistence of collaterals after a properly conducted surgical treatment of varicose veins of the lower limbs often presents a problem which is difficult to resolve. The authors put forward a simple and original method, in which a long and slightly curved triangular needle is used, without incisions, to destroy by dilaceration the collaterals whatever their degree of dilatation and their location. This technique has also been used as a first stage preceding stripping, and over a 5 year period has given results in 70 patients which are very satisfactory both from the point of view of efficacy as well as from the aesthetic point of view.

  5. Aberrant Ovarian Collateral Originating from External Iliac Artery During Uterine Artery Embolization

    SciTech Connect

    Kwon, Joon Ho; Kim, Man Deuk Lee, Kwang-hun; Lee, Myungsu; Lee, Mu Sook; Won, Jong Yun; Park, Sung Il; Lee, Do Yun

    2013-02-15

    We report a case of a 35-year-old woman who underwent uterine artery embolization (UAE) for symptomatic multiple uterine fibroids with collateral aberrant right ovarian artery that originated from the right external iliac artery. We believe that this is the first reported case in the literature of this collateral uterine flow by the right ovarian artery originated from the right external iliac artery. We briefly present the details of the case and review the literature on variations of ovarian artery origin that might be encountered during UAE.

  6. 12 CFR 221.117 - When bank in “good faith” has not relied on stock as collateral.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... the margin stock as collateral,” contained in paragraph (2)(iv) of the definition of indirectly... because of fluctuations in market value of the stock, but instead was payable on one or more fixed... stock as collateral. 221.117 Section 221.117 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED)...

  7. Methods and Technologies Branch (MTB)

    Cancer.gov

    The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.

  8. Branches in the Everett interpretation

    NASA Astrophysics Data System (ADS)

    Cunningham, Arthur J.

    2014-05-01

    Hugh Everett III describes a quantum measurement as resulting in the "branching" of the quantum state of observer and measured system, with all possible measurement outcomes represented by the ensuing branches of the total quantum state. But Everett does not specify a general rule for decomposing a quantum state into branches, and commentators have long puzzled over how, and even whether, to regard Everett's notion of branching states as physically meaningful. It is common today to appeal to decoherence considerations as a way of giving physical content to the Everettian notion of branches, but these appeals to decoherence are often regarded as considerations foreign to Everett's own approach. This paper contends that this assessment is only half right: though he does not invoke environmental decoherence, Everett does appeal to decoherence considerations, broadly understood, in his treatment of measurement. Careful consideration of his idealized models of measurement, and of the significance he ascribes to the branching of states corresponding to definite measurement outcomes, reveals that his notion of branching refers to a special physical characteristic of elements of a particular decomposition, namely the absence of interference between these component states as a result of the particular dynamics governing the evolution of the system. Characterizations of branching that appeal to the results of modern decoherence theory should therefore be regarded as a natural development of Everett's own physically meaningful conception of branching.

  9. Relationship between thrombospondin-1, endostatin, angiopoietin-2, and coronary collateral development in patients with chronic total occlusion

    PubMed Central

    Qin, Qing; Qian, Juying; Ma, Jianying; Ge, Lei; Ge, Junbo

    2016-01-01

    Abstract This study is aimed to investigate whether serum angiostatic factors (thrombospondin-1 [TSP-1] and endostatin) or angiogenic factors (angiopoietin-2 [Ang-2]) are related to coronary collateral vessel development in patients with chronic total occlusion (CTO). A total of 149 patients were enrolled in the study, and 39 patients with coronary artery disease but without significant stenosis were included in control group. In 110 patients with CTO lesion, 79 with Rentrop grades 2 to 3 collaterals were grouped as good collateral, while 31 with Rentrop grades 0 to 1 collaterals were grouped as poor collateral. Serum TSP-1, endostatin, and Ang-2 levels were studied. Serum endostatin level was significantly higher in poor collateral group compared with control group and good collateral group, respectively (96.2 ± 30.4 vs 77.8 ± 16.5 ng/mL, P = 0.007; 96.2 ± 30.4 vs 81.2 ± 30.4 ng/mL, P = 0.018). In multivariate analysis, decreased serum endostatin level was independently related to good coronary collateral development. Serum TSP-1 level was lower in patients with CTO compared with control group. However, no difference in TSP-1 level was detected between poor and good collateral group. The serum Ang-2 level did not show a significant difference among 3 groups. Circulatory endostatin may be a useful biomarker for coronary collateral development and potential target for therapeutic angiogenesis in patients with CTO. PMID:27537575

  10. Modeling branching in cereals.

    PubMed

    Evers, Jochem B; Vos, Jan

    2013-10-10

    Cereals and grasses adapt their structural development to environmental conditions and the resources available. The primary adaptive response is a variable degree of branching, called tillering in cereals. Especially for heterogeneous plant configurations the degree of tillering varies per plant. Functional-structural plant modeling (FSPM) is a modeling approach allowing simulation of the architectural development of individual plants, culminating in the emergent behavior at the canopy level. This paper introduces the principles of modeling tillering in FSPM, using (I) a probability approach, forcing the dynamics of tillering to correspond to measured probabilities. Such models are particularly suitable to evaluate the effect structural variables on system performance. (II) Dose-response curves, representing a measured or assumed response of tillering to an environmental cue. (III) Mechanistic approaches to tillering including control by carbohydrates, hormones, and nutrients. Tiller senescence is equally important for the structural development of cereals as tiller appearance. Little study has been made of tiller senescence, though similar concepts seem to apply as for tiller appearance.

  11. A Branch Meeting in Avon

    ERIC Educational Resources Information Center

    Vaughan, Kathryn; Coles, Alf

    2011-01-01

    The Association of Teachers of Mathematics (ATM) exists for, and is run by, its members. Branch meetings are so much more than the "grass roots" of the association--it can be a powerhouse of inspiration and creativity. In this article, the authors provide commentaries on a recent branch meeting.

  12. Collateral Damage Related to Rape and Interpersonal Violence in Higher Education

    ERIC Educational Resources Information Center

    Jones, Dan L.

    2014-01-01

    Collegiate communities are often faced with difficult situations from sexual assault, rape, and other forms of interpersonal violence. These events are not only tragic or traumatic for the individuals involved but also have ripple effects and create collateral damage within the campus community. Many universities are instituting bystander training…

  13. 10 CFR 609.15 - Default, demand, payment, and collateral liquidation.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PROJECTS THAT EMPLOY INNOVATIVE TECHNOLOGIES § 609.15 Default, demand, payment, and collateral liquidation... to such effect (without the need for consent or other action on the part of the Holders of the... Agreement, to become immediately due and payable by giving the Borrower written notice to such...

  14. Pulmonary Atresia with Ventricular Septal Defect and Major Aortopulmonary Collaterals Associated with Left Pulmonary Artery Interruption

    PubMed Central

    Mun, Da-Na; Park, Chun Soo; Kim, Young-Hwue; Goo, Hyun Woo

    2016-01-01

    A multistage plan and multidisciplinary approach are the keys to successful repair in patients with pulmonary atresia (PA) with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (MAPCAs). In this article, we present a multidisciplinary approach adopted to treat a patient with PA with VSD and MAPCAs associated with left pulmonary artery interruption. PMID:27733998

  15. CUDA-based acceleration of collateral filtering in brain MR images

    NASA Astrophysics Data System (ADS)

    Li, Cheng-Yuan; Chang, Herng-Hua

    2017-02-01

    Image denoising is one of the fundamental and essential tasks within image processing. In medical imaging, finding an effective algorithm that can remove random noise in MR images is important. This paper proposes an effective noise reduction method for brain magnetic resonance (MR) images. Our approach is based on the collateral filter which is a more powerful method than the bilateral filter in many cases. However, the computation of the collateral filter algorithm is quite time-consuming. To solve this problem, we improved the collateral filter algorithm with parallel computing using GPU. We adopted CUDA, an application programming interface for GPU by NVIDIA, to accelerate the computation. Our experimental evaluation on an Intel Xeon CPU E5-2620 v3 2.40GHz with a NVIDIA Tesla K40c GPU indicated that the proposed implementation runs dramatically faster than the traditional collateral filter. We believe that the proposed framework has established a general blueprint for achieving fast and robust filtering in a wide variety of medical image denoising applications.

  16. 12 CFR 150.320 - What is acceptable collateral for uninsured deposits?

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... collateral for self deposits or affiliate deposits under § 150.310: (a) Direct obligations of the United States, or other obligations fully guaranteed by the United States as to principal and interest. (b... to invest fiduciary funds under applicable state law. (c) Other readily marketable securities as...

  17. Hemodynamic role of ophthalmic artery collateral in internal carotid artery occlusion.

    PubMed

    Tatemichi, T K; Chamorro, A; Petty, G W; Khandji, A; Oropeza, L A; Duterte, D I; Mohr, J P

    1990-03-01

    We performed duplex and transcranial Doppler studies in 36 patients with angiographically documented internal carotid artery occlusion (ICAO) to determine the effect of ophthalmic artery collateral (OAC) on measures of vascular resistivity both proximal and distal to the occlusion. Resistance in the common carotid artery, measured by the resistivity index, was significantly lower in the group with OAC than in those without OAC, indicating a shunt to the low resistance intracranial circuit. The pulsatility index (PI) of the Doppler signal in the ipsilateral middle cerebral artery, a measure of both inflow pressure and distal vascular resistance, did not differ between those with and without OAC. However, the presence of circle of Willis collateral pathways (anterior communicating and/or posterior communicating artery) did appear to have a significant effect on pulsatility. When both were present angiographically, PI was higher than in the group with only 1 Willisian collateral. These findings suggest that OAC has a marginal effect on vascular resistance in arterial bed distal to an ICAO, while Willisian collaterals appear to have a more important role in cerebral perfusion, as measured indirectly by Doppler methods.

  18. The Collateral Effects of Behavioral Interventions: Applied Implications from JEAB, January 1993.

    ERIC Educational Resources Information Center

    Shull, Richard L.; Fuqua, R. Wayne

    1993-01-01

    A review of the January 1993 issue of the "Journal of the Experimental Analysis of Behavior" concludes that behavioral interventions produce collateral effects, but predicting those effects in applied work is complicated because of verbal and instructional influences and because of interactions among reinforcer types. (JDD)

  19. Comparing Main and Collateral Effects of Extinction and Differential Reinforcement of Alternative Behavior

    ERIC Educational Resources Information Center

    Petscher, Erin Seligson; Bailey, Jon S.

    2008-01-01

    This study evaluated the effects and collateral effects of extinction (EXT) and differential reinforcement of alternative behavior (DRA) interventions with inappropriate vocalizations and work refusal. Both interventions have been used frequently to reduce problem behaviors. The benefits of these interventions have been established yet may be…

  20. Supplemental Transcatheter Arterial Chemoembolization Through a Collateral Omental Artery: Treatment for Hepatocellular Carcinoma

    SciTech Connect

    Won, Jong Yun Lee, Do Yun; Lee, Jong Tae; Park, Sung Il; Kim, Myeong-Jin; Yoo, Hyung Sik; Suh, Sang-Hyun; Park, Sang Joon

    2003-04-15

    Purpose: To evaluate the therapeutic efficacy and safety of supplemental transcatheter arterialchemoembolization (TACE) through the extrahepatic collateral omentalartery (OA) for the treatment of hepatocellular carcinoma (HCC). Methods: We studied 21 patients with extrahepatic collaterals of the OA, among 1,512 patients with HCC who had undergone angiography. HCCs supplied by collateral OAs were located at: segment IV in seven, segment V in five, segment III in three, segment VI in three and segment VIII in three patients (Couinaud classification of segments). On preoperative CT scans, every HCC was abutting the liver surface. Adjacent omental infiltration or engorgement was noted in 11 patients. Celiac and hepatic arteriograms showed hypertrophy of the feeding OA in all patients. TACE of the OA was performed in 19 patients with an emulsion of iodized oil and doxorubicin hydrochloride.Embolization with gelatin sponge particles was added in five patients. Results: Collaterals of the OA to the HCC were found on the first to seventeenth sessions of TACE. On follow-up CT scans, five patients showed complete uptake of iodized oil in the tumor. Partial uptake of iodized oil was noted in 13 patients and no uptake in one patient. There was no serious complication that related to the omental embolization, such as omental or bowel ischemia. The cumulative survival rates from the time of the TACE of the OA were 81% at 6 months and 68% at 12 months. Conclusion: TACE of the OA is safe and has a potential therapeutic effect in the treatment of HCC.

  1. 17 CFR 22.3 - Derivatives clearing organizations: Treatment of cleared swaps customer collateral.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Derivatives clearing... Exchanges COMMODITY FUTURES TRADING COMMISSION CLEARED SWAPS § 22.3 Derivatives clearing organizations: Treatment of cleared swaps customer collateral. (a) General. A derivatives clearing organization shall...

  2. 17 CFR 22.3 - Derivatives clearing organizations: Treatment of cleared swaps customer collateral.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Derivatives clearing... Exchanges COMMODITY FUTURES TRADING COMMISSION CLEARED SWAPS § 22.3 Derivatives clearing organizations: Treatment of cleared swaps customer collateral. (a) General. A derivatives clearing organization shall...

  3. 17 CFR 22.3 - Derivatives clearing organizations: Treatment of Cleared Swaps Customer Collateral.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 17 Commodity and Securities Exchanges 1 2012-04-01 2012-04-01 false Derivatives clearing... Exchanges COMMODITY FUTURES TRADING COMMISSION CLEARED SWAPS (Eff. 4-9-2012) § 22.3 Derivatives clearing organizations: Treatment of Cleared Swaps Customer Collateral. (a) General. A derivatives clearing...

  4. 7 CFR 1434.16 - Release of the honey pledged as collateral for a loan.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... MARKETING ASSISTANCE LOAN AND LDP REGULATIONS FOR HONEY § 1434.16 Release of the honey pledged as collateral... county office. Any such approval shall not constitute a release of CCC's security interest in the... and security agreement shall not be released until all loan liability has been satisfied in full....

  5. 7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... commodities, or marketing assistance loan proceeds, after execution of the note and security agreement by CCC... 7 Agriculture 10 2014-01-01 2014-01-01 false Warehouse-stored marketing assistance loan collateral... SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH...

  6. 7 CFR 1421.106 - Warehouse-stored marketing assistance loan collateral.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... commodities, or marketing assistance loan proceeds, after execution of the note and security agreement by CCC... 7 Agriculture 10 2011-01-01 2011-01-01 false Warehouse-stored marketing assistance loan collateral... SIMILARLY HANDLED COMMODITIES-MARKETING ASSISTANCE LOANS AND LOAN DEFICIENCY PAYMENTS FOR 2008 THROUGH...

  7. Gene therapy during cardiac surgery: role of surgical technique to minimize collateral organ gene expression

    PubMed Central

    Katz, Michael G.; Swain, JaBaris D.; Fargnoli, Anthony S.; Bridges, Charles R.

    2013-01-01

    Effective gene therapy for heart failure has not yet been achieved clinically. The aim of this study is to quantitatively assess the cardiac isolation efficiency of the molecular cardiac surgery with recirculating delivery (MCARD™) and to evaluate its efficacy as a means to limit collateral organ gene expression. 1014 genome copies (GC) of recombinant adeno-associated viral vector 6 encoding green fluorescent protein under control of the cytomegalovirus promoter was delivered to the nine arrested sheep hearts. Blood samples were assessed using real-time quantitative polymerase chain reaction (RT QPCR). Collateral organ gene expression was assessed at four-weeks using immunohistochemical staining. The blood vector GC concentration in the cardiac circuit during complete isolation trended from 9.59±0.73 to 9.05±0.65 (log GC/cm3), and no GC were detectable in the systemic circuit (P<0.001). The washing procedure performed prior to relinquishing the cardiac circuit decreased the systemic blood vector GC concentration >800-fold (P<0.001), consistent with >99% isolation efficiency. Conversely, incomplete isolation resulted in equalization of vector GC concentration in the circuits, leading to robust collateral organ gene expression. MCARD™ is an efficient, clinically translatable myocardial delivery platform for cardiac specific gene therapy. The cardiac surgical techniques utilized are critically important to limit collateral organ gene expression. PMID:20861057

  8. 45 CFR 1336.67 - Security and collateral: Responsibilities of the Loan Administrator.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) As a Credit Factor. The availability of collateral security normally is considered an important... interests which may be taken by the lender include, but are not limited to, liens on real or personal... the replacement value of the property secured (whichever is less) must be taken naming the lender...

  9. 7 CFR 1980.443 - Collateral, personal and corporate guarantees and other requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... insurance. Collateral may also include assignments of leases or leasehold interest, revenues, patents, and... flow to service its debts and meets key industry standards such as those of Robert Morris Associates... when the security instruments are filed. (2) Hazard insurance with a standard mortgage clause...

  10. 7 CFR 1902.7 - Pledging collateral for deposit of funds in supervised bank accounts.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Analysis Division, that collateral has been pledged, contact should be made with the financial institution... financial institution, deposited for borrowers in supervised bank accounts, must be secured by pledging... applicant has selected or tentatively selected a financial institution for the supervised bank account,...

  11. 7 CFR 1902.7 - Pledging collateral for deposit of funds in supervised bank accounts.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Analysis Division, that collateral has been pledged, contact should be made with the financial institution... financial institution, deposited for borrowers in supervised bank accounts, must be secured by pledging... applicant has selected or tentatively selected a financial institution for the supervised bank account,...

  12. Intractable Postpartum Hemorrhage Resulting from Uterine Artery Pseudoaneurysm: Superselective Arteriographic Embolization via the Collateral Route

    SciTech Connect

    Doenmez, Halil Oztuerk, M. Halil; Guergen, Fatma; Soylu, Serra O.; Hekimoglu, Baki

    2007-04-15

    We present a patient with intractable postpartum hemorrhage resulting from uterine artery pseudoaneurysm despite bilateral hypogastric artery ligation who was successfully treated by an endovascular approach via the collateral route. Although there is a good argument for postponing surgery until transcatheter embolization has been attempted, this case shows that embolization can still be successful even if the iliac vessels have been ligated.

  13. 46 CFR 308.522 - Collateral deposit fund, letter of transmittal, Form MA-302.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Collateral deposit fund, letter of transmittal, Form MA-302. 308.522 Section 308.522 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk Cargo Insurance §...

  14. A positive approach to branching.

    PubMed

    Janssen, Bart J; Drummond, Revel S M; Ledger, Susan E; Snowden, Kimberley C

    2010-04-01

    Plants regulate the development of branches in response to environmental and developmental signals in order to maximize reproductive success. A number of hormone signals are involved in the regulation of branching and both their production and transmission affect axillary meristem outgrowth. With the identification of strigolactones as root-derived branch inhibitors it seems likely that a biochemical pathway starting from a carotenoid and resulting in production of a strigolactone hormone is present in most plants. Our observation that loss of CCD7 or CCD8 also results in production of a promoter of branching from roots shows the branching pathway has multiple levels of control which allows a high degree of sensitivity to subtle differences in environmental and developmental signals.

  15. Activity-dependent differences in function between proximal and distal Schaffer collaterals.

    PubMed

    Owen, Benjamin; Grover, Lawrence M

    2015-06-01

    Axon conduction fidelity is important for signal transmission and has been studied in various axons, including the Schaffer collateral axons of the hippocampus. Previously, we reported that high-frequency stimulation (HFS) depresses Schaffer collateral excitability when assessed by whole-cell recordings from CA3 pyramidal cells but induces biphasic excitability changes (increase followed by decrease) in extracellular recordings of CA1 fiber volleys. Here, we examined responses from proximal (whole-cell or field-potential recordings from CA3 pyramidal cell somata) and distal (field-potential recordings from CA1 stratum radiatum) portions of the Schaffer collaterals during HFS and burst stimulation in hippocampal slices. Whole-cell and dual-field-potential recordings using 10-100-Hz HFS revealed frequency-dependent changes like those previously described, with higher frequencies producing more drastic changes. Dual-field-potential recordings revealed substantial differences in the response to HFS between proximal and distal regions of the Schaffer collaterals, with proximal axons depressing more strongly and only distal axons showing an initial excitability increase. Because CA3 pyramidal neurons normally fire in short bursts rather than long high-frequency trains, we repeated the dual recordings using 100-1,000-ms interval burst stimulation. Burst stimulation produced changes similar to those during HFS, with shorter intervals causing more drastic changes and substantial differences observed between proximal and distal axons. We suggest that functional differences between proximal and distal Schaffer collaterals may allow selective filtering of nonphysiological activity while maximizing successful conduction of physiological activity throughout an extensive axonal arbor.

  16. Combined assessment of reflow and collateral blood flow by myocardial contrast echocardiography after acute reperfused myocardial infarction

    PubMed Central

    Leclercq, F; Messner-Pellenc, P; Descours, Q; Daures, J; Pasquie, J; Hager, F; Davy, J; Grolleau-Raoux, R

    1999-01-01

    OBJECTIVE—To evaluate the combined assessment of reflow and collateral blood flow by myocardial contrast echocardiography after myocardial infarction.
DESIGN—Myocardial contrast echocardiography was performed in patients with acute myocardial infarction shortly after successful coronary reperfusion (TIMI 3 patency) by direct angioplasty. Collateral flow was assessed before coronary angioplasty, and contrast reflow was evaluated 15 minutes after reperfusion. The presence of contractile reserve was assessed by low dose dobutamine echocardiography (5 to 15 µg/kg/min) at (mean (SD)) 3 (2) days after myocardial infarction. Recovery of segmental function (myocardial viability) was evaluated by resting echocardiography at a two month follow up. The study was prospective.
PATIENTS—35 consecutive patients referred for acute transmural myocardial infarction.
RESULTS—Contrast reflow was observed in 20 patients (57%) and collateral flow in 14 (40%). Contrast reflow and collateral contrast flow were both correlated with reversible dysfunction on initial dobutamine echocardiography and at follow up (p < 0.05). The presence of reflow or collateral flow on myocardial contrast echocardiography was a highly sensitive (100%) but weakly specific (60%) indicator of segmental dysfunction recovery. Simultaneous presence of contrast reflow and collateral flow was more specific of reversible dysfunction than reflow alone (90% v 60%).
CONCLUSIONS—Combined assessment of reflow and collateral blood flow enhanced the sensitivity of myocardial contrast echocardiography in predicting myocardial viability after acute, reperfused myocardial infarction. The simultaneous presence of reflow and collateral blood flow was highly specific of recovery of segmental dysfunction.


Keywords: contrast echocardiography; coronary reflow; collateral blood flow; dobutamine echocardiography; myocardial dysfunction PMID:10377311

  17. Preserved Collateral Blood Flow in the Endovascular M2CAO Model Allows for Clinically Relevant Profiling of Injury Progression in Acute Ischemic Stroke

    PubMed Central

    Little, Philip; Kvist, Ola; Grankvist, Rikard; Jonsson, Stefan; Damberg, Peter; Söderman, Michael; Arnberg, Fabian; Holmin, Staffan

    2017-01-01

    Interventional treatment regimens have increased the demand for accurate understanding of the progression of injury in acute ischemic stroke. However, conventional animal models severely inhibit collateral blood flow and mimic the malignant infarction profile not suitable for treatment. The aim of this study was to provide a clinically relevant profile of the emergence and course of ischemic injury in cases suitable for acute intervention, and was achieved by employing a M2 occlusion model (M2CAO) that more accurately simulates middle cerebral artery (MCA) occlusion in humans. Twenty-five Sprague-Dawley rats were subjected to Short (90 min), Intermediate (180 min) or Extended (600 min) transient M2CAO and examined longitudinally with interleaved diffusion-, T2- and arterial spin labeling perfusion-weighted magnetic resonance imaging before and after reperfusion. We identified a rapid emergence of cytotoxic edema within tissue regions undergoing infarction, progressing in several distinct phases in the form of subsequent moderation and then reversal at 230 min (p < 0.0001). We identified also the early emergence of vasogenic edema, which increased consistently before and after reperfusion (p < 0.0001). The perfusion of the penumbra correlated more strongly to the perfusion of adjacent tissue regions than did the perfusion of regions undergoing infarction (p = 0.0088). This was interpreted as an effect of preserved collateral blood flow during M2CAO. Accordingly, we observed only limited recruitment of penumbra regions to the infarction core. However, a gradual increase in infarction size was still occurring as late as 10 hours after M2CAO. Our results indicate that patients suffering MCA branch occlusion stand to benefit from interventional therapy for an extended time period after the emergence of ischemic injury. PMID:28068417

  18. Rare combination and transcatheter treatment during single session in an infant: Patent ductus arteriosus and major aortopulmonary collateral artery concordance.

    PubMed

    Güvenç, Osman; Ödemiş, Ender; Saygı, Murat; Demir, İbrahim Halil

    2016-10-01

    Major aortopulmonary collateral arteries are abnormal vascular structures that may be seen in cyanotic diseases that progress with reduced pulmonary flow. They occur rather rarely in the absence of cyanotic congenital heart disease. Presently described is the case of an infant who underwent patent ductus arteriosus (PDA) and major aortopulmonary collateral artery occlusion in a single session, without presence of cyanotic congenital heart disease. To the best of our knowledge, this is the first case of congenital aortopulmonary collateral artery to be reported in a symptomatic infant with PDA.

  19. In vivo single branch axotomy induces GAP-43-dependent sprouting and synaptic remodeling in cerebellar cortex.

    PubMed

    Allegra Mascaro, Anna Letizia; Cesare, Paolo; Sacconi, Leonardo; Grasselli, Giorgio; Mandolesi, Georgia; Maco, Bohumil; Knott, Graham W; Huang, Lieven; De Paola, Vincenzo; Strata, Piergiorgio; Pavone, Francesco S

    2013-06-25

    Plasticity in the central nervous system in response to injury is a complex process involving axonal remodeling regulated by specific molecular pathways. Here, we dissected the role of growth-associated protein 43 (GAP-43; also known as neuromodulin and B-50) in axonal structural plasticity by using, as a model, climbing fibers. Single axonal branches were dissected by laser axotomy, avoiding collateral damage to the adjacent dendrite and the formation of a persistent glial scar. Despite the very small denervated area, the injured axons consistently reshape the connectivity with surrounding neurons. At the same time, adult climbing fibers react by sprouting new branches through the intact surroundings. Newly formed branches presented varicosities, suggesting that new axons were more than just exploratory sprouts. Correlative light and electron microscopy reveals that the sprouted branch contains large numbers of vesicles, with varicosities in the close vicinity of Purkinje dendrites. By using an RNA interference approach, we found that downregulating GAP-43 causes a significant increase in the turnover of presynaptic boutons. In addition, silencing hampers the generation of reactive sprouts. Our findings show the requirement of GAP-43 in sustaining synaptic stability and promoting the initiation of axonal regrowth.

  20. Fault branching and rupture directivity

    NASA Astrophysics Data System (ADS)

    Fliss, Sonia; Bhat, Harsha S.; Dmowska, Renata; Rice, James R.

    2005-06-01

    Could the directivity of a complex earthquake be inferred from the ruptured fault branches it created? Typically, branches develop in forward orientation, making acute angles relative to the propagation direction. Direct backward branching of the same style as the main rupture (e.g., both right lateral) is disallowed by the stress field at the rupture front. Here we propose another mechanism of backward branching. In that mechanism, rupture stops along one fault strand, radiates stress to a neighboring strand, nucleates there, and develops bilaterally, generating a backward branch. Such makes diagnosing directivity of a past earthquake difficult without detailed knowledge of the branching process. As a field example, in the Landers 1992 earthquake, rupture stopped at the northern end of the Kickapoo fault, jumped onto the Homestead Valley fault, and developed bilaterally there, NNW to continue the main rupture but also SSE for 4 km forming a backward branch. We develop theoretical principles underlying such rupture transitions, partly from elastostatic stress analysis, and then simulate the Landers example numerically using a two-dimensional elastodynamic boundary integral equation formulation incorporating slip-weakening rupture. This reproduces the proposed backward branching mechanism based on realistic if simplified fault geometries, prestress orientation corresponding to the region, standard lab friction values for peak strength, and fracture energies characteristic of the Landers event. We also show that the seismic S ratio controls the jumpable distance and that curving of a fault toward its compressional side, like locally along the southeastern Homestead Valley fault, induces near-tip increase of compressive normal stress that slows rupture propagation.

  1. Novel side branch ostial stent.

    PubMed

    Chen, Shao-Liang; Lv, Shu-Zheng; Kwan, Tak W

    2009-04-01

    Bifurcation lesions are technically challenging and plagued by a high incidence of restenosis, especially at the side branch orifice, which results in a more frequent need for revascularization during the follow-up period. This report discusses two clinical experiences with a novel side branch ostial stent, the BIGUARD stent, designed for the treatment of bifurcation lesions; procedural success with no in-hospital complications was observed in types IVb and Ia lesions.

  2. Structural Mechanics and Dynamics Branch

    NASA Technical Reports Server (NTRS)

    Stefko, George

    2003-01-01

    The 2002 annual report of the Structural Mechanics and Dynamics Branch reflects the majority of the work performed by the branch staff during the 2002 calendar year. Its purpose is to give a brief review of the branch s technical accomplishments. The Structural Mechanics and Dynamics Branch develops innovative computational tools, benchmark experimental data, and solutions to long-term barrier problems in the areas of propulsion aeroelasticity, active and passive damping, engine vibration control, rotor dynamics, magnetic suspension, structural mechanics, probabilistics, smart structures, engine system dynamics, and engine containment. Furthermore, the branch is developing a compact, nonpolluting, bearingless electric machine with electric power supplied by fuel cells for future "more electric" aircraft. An ultra-high-power-density machine that can generate projected power densities of 50 hp/lb or more, in comparison to conventional electric machines, which generate usually 0.2 hp/lb, is under development for application to electric drives for propulsive fans or propellers. In the future, propulsion and power systems will need to be lighter, to operate at higher temperatures, and to be more reliable in order to achieve higher performance and economic viability. The Structural Mechanics and Dynamics Branch is working to achieve these complex, challenging goals.

  3. Quantitative macroinvertebrate survey of Pen Branch and Indian Grave Branch

    SciTech Connect

    Not Available

    1989-02-01

    A total of 80 species were collected at all sites on Pen Branch and Indian Grave Branch during the 28 day period for colonization of the multiplate artificial substrate samplers. The two upstream sites demonstrated the highest species richness. During the sampling interval a release of significant proportion entered Indian Grave Branch, affecting all downstream sites. This effect was most severe at sites 3, 4, and 7, apparently resulting in heavy scouring of the multiplate samplers. Nevertheless, much colonization did occur at sites 3 and 4, with hydropsychid caddisflies, blackflies and midges predominant. At sites 5 and 6 a greater degree of recovery was noted, due to the lessened scouring in the broad floodplain. These downstream sites had significant numbers of mayflies along with the numerous midges. Considered overall, colonization during the period since the K Reactor has ceased releasing thermal effluent into Pen Branch and Indian Grave Branch has been substantial, introducing a substantial proportion of the species known from other nearby streams. 29 tabs.

  4. Intensity-based 3D/2D registration for percutaneous intervention of major aorto-pulmonary collateral arteries

    NASA Astrophysics Data System (ADS)

    Couet, Julien; Rivest-Henault, David; Miro, Joaquim; Lapierre, Chantal; Duong, Luc; Cheriet, Mohamed

    2012-02-01

    Percutaneous cardiac interventions rely mainly on the experience of the cardiologist to safely navigate inside soft tissues vessels under X-ray angiography guidance. Additional navigation guidance tool might contribute to improve reliability and safety of percutaneous procedures. This study focus on major aorta-pulmonary collateral arteries (MAPCAs) which are pediatric structures. We present a fully automatic intensity-based 3D/2D registration method that accurately maps pre-operatively acquired 3D tomographic vascular data of a newborn patient over intra-operatively acquired angiograms. The tomographic dataset 3D pose is evaluated by comparing the angiograms with simulated X-ray projections, computed from the pre-operative dataset with a proposed splatting-based projection technique. The rigid 3D pose is updated via a transformation matrix usually defined in respect of the C-Arm acquisition system reference frame, but it can also be defined in respect of the projection plane local reference frame. The optimization of the transformation is driven by two algorithms. First the hill climbing local search and secondly a proposed variant, the dense hill climbing. The latter makes the search space denser by considering the combinations of the registration parameters instead of neighboring solutions only. Although this study focused on the registration of pediatric structures, the same procedure could be applied for any cardiovascular structures involving CT-scan and X-ray angiography. Our preliminary results are promising that an accurate (3D TRE 0.265 +/- 0.647mm) and robust (99% success rate) bi-planes registration of the aorta and MAPCAs from a initial displacement up to 20mm and 20° can be obtained within a reasonable amount of time (13.7 seconds).

  5. Placement of a port catheter through collateral veins in a patient with central venous occlusion.

    PubMed

    Teichgräber, Ulf Karl-Martin; Streitparth, Florian; Gebauer, Bernhard; Benter, Thomas

    2010-04-01

    Long-term utilization of central venous catheters (CVCs) for parenteral nutrition has a high incidence of central venous complications including infections, occlusions, and stenosis. We report the case of a 31-year-old woman presenting with a malabsorption caused by short gut syndrome due to congenital aganglionic megacolon. The patient developed a chronic occlusion of all central neck and femoral veins due to long-term use of multiple CVCs over more than 20 years. In patients with central venous occlusion and venous transformation, the implantation of a totally implanted port system by accessing collateral veins is an option to continue long-term parenteral nutrition when required. A 0.014-in. Whisper guidewire (Terumo, Tokyo) with high flexibility and steerability was chosen to maneuver and pass through the collateral veins. We suggest this approach to avoid unfavorable translumbar or transhepatic central venous access and to conserve the anatomically limited number of percutaneous access sites.

  6. [Chinese translation of "nerve" and its influences on research of meridians and collaterals].

    PubMed

    Li, Su-Yun; Zhao, Jing-Sheng

    2011-05-01

    Authors investigated the whole introduction and translation course of the word "nerve" into China during the Ming dynasty (1368-1644), Qing dynasty(1644-1911) and the Republic of China (1912-1949), when western medicine was introduced into the East, as well as its influences on the cognition and researches of meridians and collaterals. The result shows that "nerve" was once translated into "Xijin" and "Naoqijin" in the Ming and Qing dynasties. Only until the period of the late Qing dynasty and the early stage of the Republic of China, the word "Shenjing", which is known as the unique Chinese translation of nerve nowadays, was introduced from Japan. From that time on, the Chinese physicians started to explore the relation between nerves and meridians, which led to the transform of the academic methodology on essence of meridian. Thus, profound as well as prolong influences were made on study of meridians and collaterals until nowadays.

  7. Portal hypertension: Imaging of portosystemic collateral pathways and associated image-guided therapy.

    PubMed

    Bandali, Murad Feroz; Mirakhur, Anirudh; Lee, Edward Wolfgang; Ferris, Mollie Clarke; Sadler, David James; Gray, Robin Ritchie; Wong, Jason Kam

    2017-03-14

    Portal hypertension is a common clinical syndrome, defined by a pathologic increase in the portal venous pressure. Increased resistance to portal blood flow, the primary factor in the pathophysiology of portal hypertension, is in part due to morphological changes occurring in chronic liver diseases. This results in rerouting of blood flow away from the liver through collateral pathways to low-pressure systemic veins. Through a variety of computed tomographic, sonographic, magnetic resonance imaging and angiographic examples, this article discusses the appearances and prevalence of both common and less common portosystemic collateral channels in the thorax and abdomen. A brief overview of established interventional radiologic techniques for treatment of portal hypertension will also be provided. Awareness of the various imaging manifestations of portal hypertension can be helpful for assessing overall prognosis and planning proper management.

  8. [Practice on the case-based teaching innovation of Science of Meridians, Collaterals and Acupoints].

    PubMed

    Yin, Zhen-Jin; Zhang, Shu-Feng; Yan, Yuan-Jie; Bao, Hong-Ling; Wang, Bei-Bei

    2012-12-01

    The case-based teaching method which is applied to the teaching of Science of Meridians, Collaterals and Acupoints is discussed in this paper, in which the typical cases such as the growth of the acupuncture-moxibustion eminent physicians, the application of acupoints by the eminent physicians and the experiences in the acupoint combination are integrated. The students are instructed to launch the clinical practical activity through establishing the clinical base of Science of Meridians, Collaterals and Acupoints, in association with the true cases. It is proved that the case-based teaching method can promote the training of the manipulation techniques of the students and the inheritance of the experiences of eminent physicians in higher education.

  9. Spatially Interpolated Disease Prevalence Estimation Using Collateral Indicators of Morbidity and Ecological Risk

    PubMed Central

    Congdon, Peter

    2013-01-01

    This paper considers estimation of disease prevalence for small areas (neighbourhoods) when the available observations on prevalence are for an alternative partition of a region, such as service areas. Interpolation to neighbourhoods uses a kernel method extended to take account of two types of collateral information. The first is morbidity and service use data, such as hospital admissions, observed for neighbourhoods. Variations in morbidity and service use are expected to reflect prevalence. The second type of collateral information is ecological risk factors (e.g., pollution indices) that are expected to explain variability in prevalence in service areas, but are typically observed only for neighbourhoods. An application involves estimating neighbourhood asthma prevalence in a London health region involving 562 neighbourhoods and 189 service (primary care) areas. PMID:24129116

  10. Outcome review on the percutaneous release of the proximal interphalangeal joint accessory collateral ligaments

    PubMed Central

    Cerovac, Sonja; Stanley, John

    2009-01-01

    The percutaneous release of accessory collateral ligaments was introduced in 1986 as a safe and quick procedure to be attempted before open, more extensive joint release in the treatment of proximal interphalangeal joint flexion contracture. Our study analyzed the long-term results and patient satisfaction following a percutaneous release in 30 joints after a mean follow-up period of 34 months. In one half of cases the preoperative joint flexion deformity was reduced from 78° to 34°. The best results were observed in patients with osteoarthritis and stiff, immobilized joints. In patients with inflammatory arthritides, marked intraoperative correction was maintained rarely, joint contractures recurred early, and patients were unsatisfied. There were no intraoperative complications. Percutaneous release of the accessory collateral ligaments can produce a long lasting correction of the joint contracture, but careful patient selection and strict postoperative rehabilitation are essential for favorable outcome. PMID:21808681

  11. Sphingosine-1-Phosphate Receptor-1 Selective Agonist Enhances Collateral Growth and Protects against Subsequent Stroke

    PubMed Central

    Ichijo, Masahiko; Ishibashi, Satoru; Li, Fuying; Yui, Daishi; Miki, Kazunori; Mizusawa, Hidehiro; Yokota, Takanori

    2015-01-01

    Background and Purpose Collateral growth after acute occlusion of an intracranial artery is triggered by increasing shear stress in preexisting collateral pathways. Recently, sphingosine-1-phosphate receptor-1 (S1PR1) on endothelial cells was reported to be essential in sensing fluid shear stress. Here, we evaluated the expression of S1PR1 in the hypoperfused mouse brain and investigated the effect of a selective S1PR1 agonist on leptomeningeal collateral growth and subsequent ischemic damage after focal ischemia. Methods In C57Bl/6 mice (n = 133) subjected to unilateral common carotid occlusion (CCAO) and sham surgery. The first series examined the time course of collateral growth, cell proliferation, and S1PR1 expression in the leptomeningeal arteries after CCAO. The second series examined the relationship between pharmacological regulation of S1PR1 and collateral growth of leptomeningeal anastomoses. Animals were randomly assigned to one of the following groups: LtCCAO and daily intraperitoneal (ip) injection for 7 days of an S1PR1 selective agonist (SEW2871, 5 mg/kg/day); sham surgery and daily ip injection for 7 days of SEW2871 after surgery; LtCCAO and daily ip injection for 7 days of SEW2871 and an S1PR1 inverse agonist (VPC23019, 0.5 mg/kg); LtCCAO and daily ip injection of DMSO for 7 days after surgery; and sham surgery and daily ip injection of DMSO for 7 days. Leptomeningeal anastomoses were visualized 14 days after LtCCAO by latex perfusion method, and a set of animals underwent subsequent permanent middle cerebral artery occlusion (pMCAO) 7days after the treatment termination. Neurological functions 1hour, 1, 4, and 7days and infarction volume 7days after pMCAO were evaluated. Results In parallel with the increase in S1PR1 mRNA levels, S1PR1 expression colocalized with endothelial cell markers in the leptomeningeal arteries, increased markedly on the side of the CCAO, and peaked 7 days after CCAO. Mitotic cell numbers in the leptomeningeal arteries

  12. Evidence of primary, secondary, and collateral paraphilias left at serial murder and sex offender crime scenes.

    PubMed

    White, John H

    2007-09-01

    This paper is a descriptive review of the phenomenon of paraphilias, the relationship of possessing multiple paraphilias with the commission of sexual crimes and serial murder and the recognition of evidence related to sexual crimes committed by offenders with paraphilias. Several case studies are presented and the manifestations of multiple paraphilias, such as those experienced by Jeffrey Dahmer, Albert Fish, and others, are conceptualized and divided into three types: (i) replacement--no overlap; (ii) replacement with overlap; and (iii) cumulative. The categories are further divided into primary, secondary, and collateral paraphilias. Primary and secondary paraphilias are mutually exclusive and one does not build upon the other. Collateral paraphilias may serve to enhance the overall sexual experience of the primary and secondary paraphilias, including the sexualization of props or weapons. Implications for criminalists and criminal investigators are explained, particularly the value in discerning hidden as well as salient evidence of paraphilic behaviors left at crime scenes.

  13. Portal hypertension: Imaging of portosystemic collateral pathways and associated image-guided therapy

    PubMed Central

    Bandali, Murad Feroz; Mirakhur, Anirudh; Lee, Edward Wolfgang; Ferris, Mollie Clarke; Sadler, David James; Gray, Robin Ritchie; Wong, Jason Kam

    2017-01-01

    Portal hypertension is a common clinical syndrome, defined by a pathologic increase in the portal venous pressure. Increased resistance to portal blood flow, the primary factor in the pathophysiology of portal hypertension, is in part due to morphological changes occurring in chronic liver diseases. This results in rerouting of blood flow away from the liver through collateral pathways to low-pressure systemic veins. Through a variety of computed tomographic, sonographic, magnetic resonance imaging and angiographic examples, this article discusses the appearances and prevalence of both common and less common portosystemic collateral channels in the thorax and abdomen. A brief overview of established interventional radiologic techniques for treatment of portal hypertension will also be provided. Awareness of the various imaging manifestations of portal hypertension can be helpful for assessing overall prognosis and planning proper management. PMID:28348478

  14. Placement of a Port Catheter Through Collateral Veins in a Patient with Central Venous Occlusion

    SciTech Connect

    Teichgraeber, Ulf Karl-Martin Streitparth, Florian; Gebauer, Bernhard; Benter, Thomas

    2010-04-15

    Long-term utilization of central venous catheters (CVCs) for parenteral nutrition has a high incidence of central venous complications including infections, occlusions, and stenosis. We report the case of a 31-year-old woman presenting with a malabsorption caused by short gut syndrome due to congenital aganglionic megacolon. The patient developed a chronic occlusion of all central neck and femoral veins due to long-term use of multiple CVCs over more than 20 years. In patients with central venous occlusion and venous transformation, the implantation of a totally implanted port system by accessing collateral veins is an option to continue long-term parenteral nutrition when required. A 0.014-in. Whisper guidewire (Terumo, Tokyo) with high flexibility and steerability was chosen to maneuver and pass through the collateral veins. We suggest this approach to avoid unfavorable translumbar or transhepatic central venous access and to conserve the anatomically limited number of percutaneous access sites.

  15. Management of medial-sided knee injuries, part 1: medial collateral ligament.

    PubMed

    Marchant, Milford H; Tibor, Lisa M; Sekiya, Jon K; Hardaker, William T; Garrett, William E; Taylor, Dean C

    2011-05-01

    The medial collateral ligament complex is a primary stabilizer that combines static and dynamic resistance to direct valgus stress while contributing significant restraints to rotatory motion and anterior-posterior translation. Varying opinions exist among investigators regarding injury classification and treatment algorithms. Whereas most agree that the majority of isolated medial collateral ligament complex injuries can be treated nonoperatively, isolated injuries with chronic instability and multiligament injuries may require operative intervention. Substantial confounding factors are present within published reports, making comparative analyses and systematic review challenging. This review focuses on the anatomy and biomechanics of the medial structures of the knee; it discusses the clinical evaluation of complex injuries; and it reviews nonoperative and operative treatment methods.

  16. The receptor for advanced glycation end products impairs collateral formation in both diabetic and non-diabetic mice.

    PubMed

    Hansen, Laura M; Gupta, Divya; Joseph, Giji; Weiss, Daiana; Taylor, W Robert

    2017-01-01

    Diabetics often have poor perfusion in their limbs as a result of peripheral artery disease and an impaired ability to generate collateral vessels. The receptor for advanced glycation end products (RAGE) is one protein that is thought to play a detrimental role in collateral development in diabetics due to increased levels of advanced glycation end products (AGE), one of its ligands, in diabetes. Thus, the aim of this study was to investigate the role of RAGE in both diabetic and non-diabetic settings in a model of collateral formation in mice. Streptozotocin was used to induce diabetes in both wild type and RAGE knockout mice. Increased levels of the AGE, N(ɛ)-(carboxymethyl) lysine (CML), were confirmed via an ELISA. A hindlimb ischemia model, in which the femoral artery is ligated, was used to drive collateral growth and reperfusion was assessed using laser Doppler perfusion imaging and histological analysis of vessels in the muscle. Both of these measurements showed impaired collateral growth in diabetic compared with wild-type mice as well as improved collateral growth in both diabetic and non-diabetic RAGE knockout mice when compared their wild-type counterparts. Distance on a freely accessed running wheel, used as a measure of perfusion recovery, showed that wild-type diabetic mice had functionally impaired recovery compared with their wild-type counterparts. Immunohistochemistry and immunoblotting showed that HMGB-1 (high-mobility group box 1), another RAGE ligand, was increased in the ischemic leg compared with the non-ischemic leg in all mice. This increase in HMGB-1 may explain improvement in animals lacking RAGE and its subsequent signaling. In conclusion, this study shows that RAGE impairs collateral growth in a diabetic setting and also in a non-diabetic setting. This demonstrates the importance of RAGE and alternate RAGE ligands in the setting of collateral vessel growth.

  17. Arterial Spin-Labeling MRI Can Identify the Presence and Intensity of Collateral Perfusion in Patients With Moyamoya Disease

    PubMed Central

    Zaharchuk, Greg; Do, Huy M.; Marks, Michael P.; Rosenberg, Jarrett; Moseley, Michael E.; Steinberg, Gary K.

    2011-01-01

    Background and Purpose Determining the presence and adequacy of collateral blood flow is important in cerebrovascular disease. Therefore, we explored whether a noninvasive imaging modality, arterial spin labeling (ASL) MRI, could be used to detect the presence and intensity of collateral flow using digital subtraction angiography (DSA) and stable xenon CT cerebral blood flow as gold standards for collaterals and cerebral blood flow, respectively. Methods ASL and DSA were obtained within 4 days of each other in 18 patients with Moyamoya disease. Two neurointerventionalists scored DSA images using a collateral grading scale in regions of interest corresponding to ASPECTS methodology. Two neuroradiologists similarly scored ASL images based on the presence of arterial transit artifact. Agreement of ASL and DSA consensus scores was determined, including kappa statistics. In 15 patients, additional quantitative xenon CT cerebral blood flow measurements were performed and compared with collateral grades. Results The agreement between ASL and DSA consensus readings was moderate to strong, with a weighted kappa value of 0.58 (95% confidence interval, 0.52–0.64), but there was better agreement between readers for ASL compared with DSA. Sensitivity and specificity for identifying collaterals with ASL were 0.83 (95% confidence interval, 0.77–0.88) and 0.82 (95% confidence interval, 0.76–0.87), respectively. Xenon CT cerebral blood flow increased with increasing DSA and ASL collateral grade (P<0.05). Conclusions ASL can noninvasively predict the presence and intensity of collateral flow in patients with Moyamoya disease using DSA as a gold standard. Further study of other cerebrovascular diseases, including acute ischemic stroke, is warranted. PMID:21799169

  18. Combat Stress: A Collateral Effect in the Operational Effectiveness Loss Multiplier (OELM) Methodology

    DTIC Science & Technology

    2015-02-01

    5202, Draft Final (Alexandria, VA: IDA, April 2015), 10-4. 14 North Atlantic Treaty Organization (NATO) Standardization Agency ( NSA ), NATO Glossary of...Belgium: NSA , 2012), 2-C-2. 15 Disraelly et al., “A New Methodology for CBRN Casualty Estimation,” 228. 16 Disraelly et al., A Methodology for...20 NATO NSA , AAP-06, 2-K-1. 21 Ibid., 2-D-6. 22 Disraelly et al., A Methodology for Examining Collateral Effects on Military Operations during

  19. Combat Stress: A Collateral Effect in the Operational Effectiveness Loss Multiplier (OELM) Methodology

    DTIC Science & Technology

    2015-02-01

    Organization (NATO) Standardization Agency ( NSA ), NATO Glossary of Terms and Definitions (English and French), Allied Administration Publication (AAP)-06...Edition 2012 Version 2 (hereafter referred to as AAP-06) (Belgium: NSA , 2012), 2-C-2. 15 Disraelly et al., “A New Methodology for CBRN Casualty...20 NATO NSA , AAP-06, 2-K-1. 21 Ibid., 2-D-6. 22 Disraelly et al., A Methodology for Examining Collateral Effects on Military Operations during

  20. Post traumatic osteoma of tibial insertion of medial collateral ligament of knee joint.

    PubMed

    Shanker, V S; Gadikoppula, S; Loeffler, M D

    1998-03-01

    Two cases are presented of post traumatic para-articular osteoma developing at the site of tibial attachment of the medial collateral ligament of knee joint. These occurred after injuries sustained while playing football and in one case the ossified mass was treated with surgical excision for unresolved symptoms after conservative measures. A comparison is made with Pellegrini Stieda disease, which is a similar affection of the femoral insertion of the medial ligament of the knee joint.

  1. [Does ST-elevation in stress ECG depend on the extent of collateral circulation?].

    PubMed

    Bettinger, R; Wendt, T; Klepzig, H; Kaltenbach, M

    1993-01-01

    As a possible cause of exercise-induced ST-elevation in patients without myocardial infarction, a poor or absent coronary circulation to the poststenotic coronary segment was postulated. To check this thesis, we examined 10 patients (pts.) with ST-elevation, respectively, ST-depression and comparable coronary status (coronary score 12 vs. 12; mean stenosis diameter 86 vs. 85%) and exercise parameters (work load 150 vs. 137.5 Watts; exercise duration 2.8 vs 3.5 min) with regard to their collateral circulation. In the group with ST-elevation there were nine pts. with severe proximal stenosis of the left anterior descending artery (LAD) and one pt. with a stenosis in the middle third of the right coronary artery. The 10 patients with ST-depression had a proximal stenosis in the LAD. The extent of the angiographically seen collaterals was equal in both groups. As a result, this study demonstrates that the size of the collateral circulation has no influence on the exercise-induced ST-elevation. The most plausible cause of exercise-induced ST-elevation is a functional decrease of the lumen of a severe stenosis.

  2. Collateral Consequences of Juvenile Sex Offender Registration and Notification: Results From a Survey of Treatment Providers.

    PubMed

    Harris, Andrew J; Walfield, Scott M; Shields, Ryan T; Letourneau, Elizabeth J

    2016-12-01

    Among many in the research, policy, and practice communities, the application of sex offender registration and notification (SORN) to juveniles who sexually offend (JSO) has raised ongoing concerns regarding the potential collateral impacts on youths' social, mental health, and academic adjustment. To date, however, no published research has systematically examined these types of collateral consequences of juvenile SORN. Based on a survey of a national sample of treatment providers in the United States, this study investigates the perceived impact of registration and notification on JSO across five key domains: mental health, harassment and unfair treatment, school problems, living instability, and risk of reoffending. Results indicate that treatment providers overwhelmingly perceive negative consequences associated with registration with an incremental effect of notification indicating even greater concern across all five domains. Providers' demographics, treatment modalities, and client profile did not influence their perceptions of the collateral consequences suggesting that provider concern about the potential harm of SORN applied to juveniles is robust. Policy implications are discussed.

  3. Comparison of gradient echo with spin echo magnetic resonance imaging and echocardiography in the evaluation of major aortopulmonary collateral arteries.

    PubMed

    Vick, G W; Wendt, R E; Rokey, R

    1994-05-01

    This study compared gradient echo magnetic resonance imaging, spin echo magnetic resonance imaging, echocardiography, and echocardiography with x-ray cineangiography in the evaluation of major aortopulmonary collateral arteries. Twelve patients (ages 9 months to 35 years, mean 11 +/- 11 years) with known or suspected major aortopulmonary collateral arteries were studied. The aortic insertion and proximal course of 29 major aortopulmonary collateral arteries demonstrated by x-ray contrast angiography were shown in all 29 cases by gradient echo magnetic resonance imaging but in only 23 of the 29 cases by spin echo magnetic resonance imaging. Color Doppler-echocardiography detected aortopulmonary collateral arteries in four patients but did not define the proximal course or distal anatomy. Gradient echo images of distal aortopulmonary collateral anatomy were qualitatively superior to spin echo images. The contrast-to-noise ratio between the vessel lumen and adjacent lung was greater for gradient echo (6.06 +/- 2.91) than for spin echo (1.45 +/- 1.13)(p < 0.05). Gradient echo magnetic resonance imaging is a useful method for identification and characterization of aortopulmonary collateral arteries in patients of all ages and is superior to spin echo magnetic resonance imaging and echocardiography.

  4. The association between prolongation in QRS duration and presence of coronary collateral circulation in patients with acute myocardial infarction

    PubMed Central

    Altıntaş, Bernas; Uğurlu, Murat; Kaya, İlyas; Uçaman, Berzal; Uluğ, Ali Veysel; Altındağ, Rojhat; Altaş, Yakup; Adıyaman, Mehmet Şahin; Öztürk, Önder

    2016-01-01

    Background It is known that QRS duration is related to prognosis in acute myocardial infarction. The relation between QRS duration and coronary collateral circulation is uncertain. In the present study, we aimed to determine the relation between QRS duration and coronary collateral circulation in patients admitted with acute myocardial infarction. Methods The present study was composed of 109 consecutive patients with acute myocardial infarction. All patients had total occlusion in the left anterior descending coronary artery. Electrocardiographic recordings on admission were obtained for the assessment of QRS duration. The Rentrop classification was used to define coronary collateral circulation on coronary angiography. Patients were divided into two groups as follows: Group 1 with poor coronary collateral circulation (Rentrop 0–1) and Group 2 with good coronary collateral circulation (Rentrop 2–3). Results Of all patients, 62 patients were included in group 1 and 47 patients in group 2, respectively. In the present study, patients in the group 1 had longer QRS duration than patients in the group 2 (p < 0.005). Additionally, we found that Rentrop grading had negative correlation with both QRS duration and white blood cell count (r: −0.28; p < 0.005 and r: −0.35; p < 0.001). Conclusion Our study showed that there was an inverse relationship between QRS duration on admission and presence of coronary collateral circulation in patients with acute myocardial infarction. PMID:27570619

  5. Collateral circulation as a marker of the presence of viable myocardium in patients with recent myocardial infarction

    SciTech Connect

    Fujita, M.; Ohno, A.; Wada, O.; Miwa, K.; Nozawa, T.; Yamanishi, K.; Sasayama, S. )

    1991-08-01

    The relationship between the presence of viable myocardium and the extent of coronary collateral circulation to the infarct area was evaluated in 20 patients with a recent anterior myocardial infarction who had complete obstruction of the left anterior descending coronary artery. The viability of myocardial tissue was assessed by exercise thallium-201 myocardial scintigraphy, and the collateral circulation was angiographically evaluated by means of a collateral index ranging from 0 to 3. Patients were divided into two groups according to the presence (group 1, n = 10) or absence (group 2, n = 10) of viable myocardium in the perfusion territory of the infarct-related artery. The collateral index in group 1 was 2.5 {plus minus} 0.5 (SD), which was significantly higher than the 0.7 {plus minus} 0.8 in group 2. These findings indicate that the presence of ischemic but viable myocardium is intimately related to the development of collateral circulation in patients with myocardial infarction, and the existence of well-developed collateral channels predicts the presence of viable myocardium in the infarct area.

  6. Synaptic gating at axonal branches, and sharp-wave ripples with replay: a simulation study

    PubMed Central

    Vladimirov, Nikita; Tu, Yuhai; Traub, Roger D.

    2016-01-01

    Mechanisms of place cell replay occurring during sharp-wave ripples (SPW-Rs) remain obscure due to the fact that ripples in vitro depend on non-synaptic mechanisms, presumably via axo-axonal gap junctions between pyramidal cells. We suggest a model of in vivo SPW-Rs in which synaptic excitatory post-synaptic potentials (EPSPs) control the axonal spiking of cells in SPW-Rs: ripple activity remains hidden in the network of axonal collaterals (connected by gap junctions) due to conduction failures, unless there is a sufficient dendritic EPSP. The EPSP brings the axonal branching point to threshold, and action potentials from the collateral start to propagate to the soma and to the distal axon. The model coherently explains multiple experimental data on SPW-Rs, both in vitro and in vivo. The mechanism of synaptic gating leads to the following implication: a sequence of pyramidal cells can be replayed at ripple frequency by the superposition of subthreshold dendritic EPSPs and ripple activity in the axonal plexus. Replay is demonstrated in both forward and reverse directions. We discuss several testable predictions. In general, the mechanism of synaptic gating suggests that pyramidal cells under certain conditions can act like a transistor. PMID:23992155

  7. Fault Branching and Rupture Directivity

    NASA Astrophysics Data System (ADS)

    Dmowska, R.; Rice, J. R.; Kame, N.

    2002-12-01

    Can the rupture directivity of past earthquakes be inferred from fault geometry? Nakata et al. [J. Geogr., 1998] propose to relate the observed surface branching of fault systems with directivity. Their work assumes that all branches are through acute angles in the direction of rupture propagation. However, in some observed cases rupture paths seem to branch through highly obtuse angles, as if to propagate ``backwards". Field examples of that are as follows: (1) Landers 1992. When crossing from the Johnson Valley to the Homestead Valley (HV) fault via the Kickapoo (Kp) fault, the rupture from Kp progressed not just forward onto the northern stretch of the HV fault, but also backwards, i.e., SSE along the HV [Sowers et al., 1994, Spotila and Sieh, 1995, Zachariasen and Sieh, 1995, Rockwell et al., 2000]. Measurements of surface slip along that backward branch, a prominent feature of 4 km length, show right-lateral slip, decreasing towards the SSE. (2) At a similar crossing from the HV to the Emerson (Em) fault, the rupture progressed backwards along different SSE splays of the Em fault [Zachariasen and Sieh, 1995]. (3). In crossing from the Em to Camp Rock (CR) fault, again, rupture went SSE on the CR fault. (4). Hector Mine 1999. The rupture originated on a buried fault without surface trace [Li et al., 2002; Hauksson et al., 2002] and progressed bilaterally south and north. In the south it met the Lavic Lake (LL) fault and progressed south on it, but also progressed backward, i.e. NNW, along the northern stretch of the LL fault. The angle between the buried fault and the northern LL fault is around -160o, and that NNW stretch extends around 15 km. The field examples with highly obtuse branch angles suggest that there may be no simple correlation between fault geometry and rupture directivity. We propose that an important distinction is whether those obtuse branches actually involved a rupture path which directly turned through the obtuse angle (while continuing

  8. Elevated 20-HETE impairs coronary collateral growth in metabolic syndrome via endothelial dysfunction.

    PubMed

    Joseph, Gregory; Soler, Amanda; Hutcheson, Rebecca; Hunter, Ian; Bradford, Chastity; Hutcheson, Brenda; Gotlinger, Katherine H; Jiang, Houli; Falck, John R; Proctor, Spencer; Schwartzman, Michal Laniado; Rocic, Petra

    2017-03-01

    Coronary collateral growth (CCG) is impaired in metabolic syndrome (MetS). microRNA-145 (miR-145-Adv) delivery to our rat model of MetS (JCR) completely restored and neutrophil depletion significantly improved CCG. We determined whether low endogenous levels of miR-145 in MetS allowed for elevated production of 20-hydroxyeicosatetraenoic acid (20-HETE), which, in turn, resulted in excessive neutrophil accumulation and endothelial dysfunction leading to impaired CCG. Rats underwent 0-9 days of repetitive ischemia (RI). RI-induced cardiac CYP4F (neutrophil-specific 20-HETE synthase) expression and 20-HETE levels were increased (4-fold) in JCR vs. normal rats. miR-145-Adv and 20-HETE antagonists abolished and neutrophil depletion (blocking antibodies) reduced (~60%) RI-induced increases in CYP4F expression and 20-HETE production in JCR rats. Impaired CCG in JCR rats (collateral-dependent blood flow using microspheres) was completely restored by 20-HETE antagonists [collateral-dependent zone (CZ)/normal zone (NZ) flow ratio was 0.76 ± 0.07 in JCR + 20-SOLA, 0.84 ± 0.05 in JCR + 20-HEDGE vs. 0.11 ± 0.02 in JCR vs. 0.84 ± 0.03 in normal rats]. In JCR rats, elevated 20-HETE was associated with excessive expression of endothelial adhesion molecules and neutrophil infiltration, which were reversed by miR-145-Adv. Endothelium-dependent vasodilation of coronary arteries, endothelial nitric oxide synthase (eNOS) Ser1179 phosphorylation, eNOS-dependent NO(·-) production and endothelial cell survival were compromised in JCR rats. These parameters of endothelial dysfunction were completely reversed by 20-HETE antagonism or miR-145-Adv delivery, whereas neutrophil depletion resulted in partial reversal (~70%). We conclude that low miR-145 in MetS allows for increased 20-HETE, mainly from neutrophils, which compromises endothelial cell survival and function leading to impaired CCG. 20-HETE antagonists could provide viable therapy for restoration of CCG in MetS.NEW & NOTEWORTHY

  9. Hemodynamic contribution of transdural collateral flow in adult patients with moyamoya disease.

    PubMed

    Hong, Ji Man; Hong, Yoon Hee; Lee, Seong-Joon; Lee, Sung Eun; Lee, Jin Soo; Shin, Dong Hoon

    2016-12-01

    To evaluate the hemodynamic contributions of collateral flow in adult patients with moyamoya disease, neurological deterioration or fluctuation during admission, Suzuki grade, various collateral routes, lesion volume, cerebral blood flow (CBF), and their associations were analyzed. Thirty patients (60 cerebral hemispheres, mean age 45 ± 25 years, and 73.3 % female) who were diagnosed with moyamoya disease or syndrome were enrolled over 3 years. Moyamoya stages from each hemisphere were stratified according to the Suzuki's criteria through six-vessel angiography into internal carotid arteries (ICAs), external carotid arteries (ECAs), and vertebral arteries (VAs). Collateral routes were categorized into the circle of Willis, leptomeningeal, and transdural. The volume of ipsilateral infarction was analyzed by magnetic resonance imaging. CBF volume was measured using color-coded duplex sonography. Suzuki's grade was inversely correlated with flow volume of the ICAs (p < 0.001), whereas no association was found with that of the ECAs (p = 0.445) or VAs (p = 0.096). Among hemispheres with ≥ grade 3 (n = 36), patients with transdural ECA collateral flow had less neurological deterioration or fluctuation (0.0 vs. 30.8 %, p = 0.047), smaller lesion volume (2.4 ± 3.6 vs. 27.6 ± 59.3 mL, p = 0.041), lower ICA flow (88.4 ± 45.9 vs. 146.2 ± 121.7 mL/min, p = 0.022), higher ECA flow (205.7 ± 77.7 vs. 135.9 ± 52.7 mL/min, p = 0.046), and a higher ECA/ICA flow volume ratio (31.8 ± 92.8 vs. 1.7 ± 1.9, p = 0.024). Our results suggest that ICA flow volume is inversely correlated with Suzuki grade, and that transdural ECA collaterals appear to be an important detour in adult patients with advanced stage moyamoya disease, suggesting a protector against an impending ischemic attack.

  10. 30 CFR 57.6403 - Branch circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Branch circuits. 57.6403 Section 57.6403... Blasting-Surface and Underground § 57.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits, each branch shall be equipped with a safety switch or equivalent method to isolate...

  11. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Branch circuits. 56.6403 Section 56.6403... Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits, each branch shall be equipped with a safety switch or equivalent method to isolate the circuits to be used....

  12. 17 CFR 166.4 - Branch offices.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Branch offices. 166.4 Section... RULES § 166.4 Branch offices. Each branch office of each Commission registrant must use the name of the.... The act, omission or failure of any person acting for the branch office, within the scope of...

  13. Double-branched vortex generator

    NASA Technical Reports Server (NTRS)

    Cantwell, E. R.; Westphal, R. V.; Mehta, R. D.

    1985-01-01

    In order to assess the suitability of using a double branched vortex generator in parametric studies involving vortex interactions, an experimental study of the main vortex and secondary flows produced by a double branched vortex generator was conducted in a 20-by-40 cm indraft wind tunnel. Measurements of the cross flow velocities were made with a five hole pressure probe from which vorticity contours and vortex parameters were derived. The results showed that the optimum configuration consisted of chord extensions with the absence of a centerbody.

  14. Legislative Branch Appropriations Act, 2010

    THOMAS, 111th Congress

    Rep. Wasserman Schultz, Debbie [D-FL-20

    2009-06-17

    10/01/2009 Became Public Law No: 111-68. (PDF) (All Actions) Notes: Division A is the Legislative Branch Appropriations Act, 2010. Division B is the Continuing Appropriations Resolution, 2010. Tracker: This bill has the status Became LawHere are the steps for Status of Legislation:

  15. Legislative Branch Appropriations Act, 2010

    THOMAS, 111th Congress

    Rep. Wasserman Schultz, Debbie [D-FL-20

    2009-06-17

    10/01/2009 Became Public Law No: 111-68. (TXT | PDF) (All Actions) Notes: Division A is the Legislative Branch Appropriations Act, 2010. Division B is the Continuing Appropriations Resolution, 2010. Tracker: This bill has the status Became LawHere are the steps for Status of Legislation:

  16. Branching of keratin intermediate filaments.

    PubMed

    Nafeey, Soufi; Martin, Ines; Felder, Tatiana; Walther, Paul; Felder, Edward

    2016-06-01

    Keratin intermediate filaments (IFs) are crucial to maintain mechanical stability in epithelial cells. Since little is known about the network architecture that provides this stiffness and especially about branching properties of filaments, we addressed this question with different electron microscopic (EM) methods. Using EM tomography of high pressure frozen keratinocytes, we investigated the course of several filaments in a branching of a filament bundle. Moreover we found several putative bifurcations in individual filaments. To verify our observation we also visualized the keratin network in detergent extracted keratinocytes with scanning EM. Here bifurcations of individual filaments could unambiguously be identified additionally to bundle branchings. Interestingly, identical filament bifurcations were also found in purified keratin 8/18 filaments expressed in Escherichia coli which were reassembled in vitro. This excludes that an accessory protein contributes to the branch formation. Measurements of the filament cross sectional areas showed various ratios between the three bifurcation arms. This demonstrates that intermediate filament furcation is very different from actin furcation where an entire new filament is attached to an existing filament. Instead, the architecture of intermediate filament bifurcations is less predetermined and hence consistent with the general concept of IF formation.

  17. NCI: DCTD: Biometric Research Branch

    Cancer.gov

    The Biometric Research Branch (BRB) is the statistical and biomathematical component of the Division of Cancer Treatment, Diagnosis and Centers (DCTDC). Its members provide statistical leadership for the national and international research programs of the division in developmental therapeutics, developmental diagnostics, diagnostic imaging and clinical trials.

  18. NCI: DCTD: Biometric Research Branch

    Cancer.gov

    The Biometric Research Branch (BRP) is the statistical and biomathematical component of the Division of Cancer Treatment, Diagnosis and Centers (DCTDC). Its members provide statistical leadership for the national and international research programs of the division in developmental therapeutics, developmental diagnostics, diagnostic imaging and clinical trials.

  19. Risk Factor Assessment Branch (RFAB)

    Cancer.gov

    The Risk Factor Assessment Branch (RFAB) focuses on the development, evaluation, and dissemination of high-quality risk factor metrics, methods, tools, technologies, and resources for use across the cancer research continuum, and the assessment of cancer-related risk factors in the population.

  20. 76 FR 13272 - Branch Offices

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

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  1. Multiple pathways regulate shoot branching

    PubMed Central

    Rameau, Catherine; Bertheloot, Jessica; Leduc, Nathalie; Andrieu, Bruno; Foucher, Fabrice; Sakr, Soulaiman

    2015-01-01

    Shoot branching patterns result from the spatio-temporal regulation of axillary bud outgrowth. Numerous endogenous, developmental and environmental factors are integrated at the bud and plant levels to determine numbers of growing shoots. Multiple pathways that converge to common integrators are most probably involved. We propose several pathways involving not only the classical hormones auxin, cytokinins and strigolactones, but also other signals with a strong influence on shoot branching such as gibberellins, sugars or molecular actors of plant phase transition. We also deal with recent findings about the molecular mechanisms and the pathway involved in the response to shade as an example of an environmental signal controlling branching. We propose the TEOSINTE BRANCHED1, CYCLOIDEA, PCF transcription factor TB1/BRC1 and the polar auxin transport stream in the stem as possible integrators of these pathways. We finally discuss how modeling can help to represent this highly dynamic system by articulating knowledges and hypothesis and calculating the phenotype properties they imply. PMID:25628627

  2. Cash efficiency for bank branches.

    PubMed

    Cabello, Julia García

    2013-01-01

    Bank liquidity management has become a major issue during the financial crisis as liquidity shortages have intensified and have put pressure on banks to diversity and improve their liquidity sources. While a significant strand of the literature concentrates on wholesale liquidity generation and on the alternative to deposit funding, the management of an inventory of cash holdings within the banks' branches is also a relevant issue as any significant improvement in cash management at the bank distribution channels may have a positive effect in reducing liquidity tensions. In this paper, we propose a simple programme of cash efficiency for the banks' branches, very easy to implement, which conform to a set of instructions to be imposed from the bank to their branches. This model proves to significantly reduce cash holdings at branches thereby providing efficiency improvements in liquidity management. The methodology we propose is based on the definition of some stochastic processes combined with renewal processes, which capture the random elements of the cash flow, before applying suitable optimization programmes to all the costs involved in cash movements. The classical issue of the Transaction Demand for the Cash and some aspects of Inventory Theory are also present. Mathematics Subject Classification (2000) C02, C60, E50.

  3. Effects of BRL 38227, sodium nitroprusside and verapamil on collateral perfusion following acute arterial occlusion in the rabbit isolated ear.

    PubMed Central

    Randall, M. D.; Griffith, T. M.

    1992-01-01

    1. We have used an isolated, buffer-perfused, rabbit ear model of acute arterial occlusion to investigate the effects of the nitrovasodilator sodium nitroprusside, the potassium channel activator BRL 38227 (the active (-)-enantiomer of cromakalim) and the calcium antagonist, verapamil, on collateral perfusion in the absence of pharmacological tone. 2. Verapamil was the most potent vasodilator (EC50 = 72.6 +/- 32.0 nM) of 5-hydroxytryptamine/histamine-induced tone in the rabbit isolated perfused ear. Sodium nitroprusside and BRL 38227 were less potent with respective EC50 values of 488 +/- 75 nM and 296 +/- 40 nM. Following inhibition of endothelium-derived relaxing factor (EDRF) synthesis, the potency of BRL 38227 was significantly (P less than 0.001) increased with an EC50 of 55.6 +/- 5.0 nM. 3. BRL 38227 at 500 nM and 3 microM induced substantial increases in collateral perfusion following arterial ligation in the absence of pharmacological tone compared to control. Furthermore 3 microM BRL 38227 completely reversed the attenuation of collateral perfusion which followed inhibition of EDRF synthesis with 100 microM NG-nitro-L-arginine methyl ester (L-NAME). 4. Sodium nitroprusside (500 nM and 3 microM) induced modest improvements in collateral perfusion in the early stages after arterial occlusion. 5. Verapamil did not influence collateral perfusion at either of the concentrations used (50 nM and 3 microM), even though it was a potent vasodilator. 6. The results of this study indicate that BRL 38227, and to a much lesser extent sodium nitroprusside, selectively improve collateral perfusion following arterial occlusion, even in the presence of effects of EDRF on acute collateralization, while verapamil has no effect.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 1 PMID:1393264

  4. Preliminary Study of the Confined, Collateral, and Combined Effects of Reading and Behavioral Interventions: Evidence for a Transactional Relationship

    ERIC Educational Resources Information Center

    Cook, Clayton R.; Dart, Evan; Collins, Tai; Restori, Alberto; Daikos, Chris; Delport, John

    2012-01-01

    Recent correlational studies provide support for a transactional relationship between reading and behavior problems. A transactional relationship implies that reading problems cause behavior problems, and vice versa. This study took this basic finding and examined its implications for intervention. Specifically, this study employed single-case…

  5. α-Adrenergic and neuropeptide Y Y1 receptor control of collateral circuit conductance: influence of exercise training

    PubMed Central

    Taylor, Jessica C; Yang, H T; Laughlin, M Harold; Terjung, Ronald L

    2008-01-01

    This study evaluated the role of α-adrenergic receptor- and neuropeptide Y (NPY) Y1 receptor-mediated vasoconstriction in the collateral circuit of the hind limb. Animals were evaluated either the same day (Acute) or 3 weeks following occlusion of the femoral artery; the 3-week animals were in turn limited to cage activity (Sed) or given daily exercise (Trained). Collateral-dependent blood flows (BFs) were measured during exercise with microspheres before and after α-receptor inhibition (phentolamine) and then NPY Y1 receptor inhibition (BIBP 3226) at the same running speed. Blood pressures (BPs) were measured above (caudal artery) and below (distal femoral artery) the collateral circuit. Arterial BPs were reduced by α-inhibition (50–60 mmHg) to ∼75 mmHg, but not further by NPY Y1 receptor inhibition. Effective experimental sympatholysis was verified by 50–100% increases (P < 0.001) in conductance of active muscles not affected by femoral occlusion with receptor inhibition. In the absence of receptor inhibition, vascular conductance of the collateral circuit was minimal in the Acute group (0.13 ± 0.02), increased over time in the Sed group (0.41 ± 0.03; P < 0.001), and increased further in the Trained group (0.53 ± 0.03; P < 0.02). Combined receptor inhibition increased collateral circuit conductances (P < 0.005), most in the Acute group (116 ± 37%; P < 0.02), as compared to the Sed (41 ± 6.6%; P < 0.001) and Trained (31 ± 5.6%; P < 0.001) groups. Thus, while the sympathetic influence of the collateral circuit remained in the Sed and Trained animals, it became less influential with time post-occlusion. Collateral conductances were collectively greater (P < 0.01) in the Trained as compared to Sed group, irrespective of the presence or absence of receptor inhibition. Conductances of the active ischaemic calf muscle, with combined receptor inhibition, were suboptimal in the Acute group, but increased in Sed and Trained animals to exceptionally high

  6. To branch or not to branch: Numerical modeling of dynamically branching faults

    NASA Astrophysics Data System (ADS)

    Dedontney, N. L.; Templeton Barrett, E. L.; Rice, J. R.; Dmowska, R.

    2009-12-01

    Branched fault geometries, and branched rupture paths, occur in strike-slip as well as dip-slip settings [e.g., Poliakov et al., JGR, 2002; Kame et al., JGR, 2003]. The Wenchuan earthquake illustrates such a branched geometry [Hubbard and Shaw, 2009] in a fold and thrust belt, and surface ruptures provide constraints on which faults were activated co-seismically. Additionally, a branched structure, the Central Basin Decollement [Shaw & Suppe, 1996], underlies the Los Angeles Basin. By simulating the dynamic rupture path selection, using explicit finite element methods here, we are able to estimate which faults should be activated under given conditions. Factors that influence coseismic branch activation have been extensively studied [Poliakov et al.; Kame et al.; Oglesby et al., 2003, 2004; Bhat et al., 2004, 2007]. The results show that the rupture velocity, pre-stress orientation and fault geometry influence rupture path selection. We show further that the ratio of σ1/σ3 (equivalently, the seismic S ratio) and the relative frictional fault strength also play a significant role in determining which faults are activated. Our methodology has recently included the use of a regularized friction routine [Ranjith & Rice, 2001; Cochard & Rice, 2000] which reduces the growth of numerical noise throughout the simulations. A difficulty arises in the treatment of surface interactions at the branch junction. When local opening does not occur there, slip on the branch fault must vanish at the junction, a constraint that we impose on the FE model. However, the FE contact routine used demands that slip always be constrained to zero on one or the other fault at such a junction, which is problematic when opening occurs. There is then no fundamental basis for constraining slip at the junction to zero on either fault, and the choice made affects the slip distributions and rupture path selection. Many analyses that we perform are elastic and the same material is used on both sides

  7. Branching processes in disease epidemics

    NASA Astrophysics Data System (ADS)

    Singh, Sarabjeet

    Branching processes have served as a model for chemical reactions, biological growth processes and contagion (of disease, information or fads). Through this connection, these seemingly different physical processes share some common universalities that can be elucidated by analyzing the underlying branching process. In this thesis, we focus on branching processes as a model for infectious diseases spreading between individuals belonging to different populations. The distinction between populations can arise from species separation (as in the case of diseases which jump across species) or spatial separation (as in the case of disease spreading between farms, cities, urban centers, etc). A prominent example of the former is zoonoses -- infectious diseases that spill from animals to humans -- whose specific examples include Nipah virus, monkeypox, HIV and avian influenza. A prominent example of the latter is infectious diseases of animals such as foot and mouth disease and bovine tuberculosis that spread between farms or cattle herds. Another example of the latter is infectious diseases of humans such as H1N1 that spread from one city to another through migration of infectious hosts. This thesis consists of three main chapters, an introduction and an appendix. The introduction gives a brief history of mathematics in modeling the spread of infectious diseases along with a detailed description of the most commonly used disease model -- the Susceptible-Infectious-Recovered (SIR) model. The introduction also describes how the stochastic formulation of the model reduces to a branching process in the limit of large population which is analyzed in detail. The second chapter describes a two species model of zoonoses with coupled SIR processes and proceeds into the calculation of statistics pertinent to cross species infection using multitype branching processes. The third chapter describes an SIR process driven by a Poisson process of infection spillovers. This is posed as a

  8. Calpain Inhibition Improves Collateral Dependent Perfusion in a Hypercholesterolemic Swine Model of Chronic Myocardial Ischemia

    PubMed Central

    Sabe, Ashraf A.; Potz, Brittany A.; Elmadhun, Nassrene Y.; Liu, Yuhong; Feng, Jun; Abid, M. Ruhul; Abbott, Jinnette D; Senger, Donald R; Sellke, Frank W.

    2015-01-01

    Background Calpain over-expression is implicated in aberrant angiogenesis. We hypothesized that calpain inhibition (CI, MDL28170) would improve collateral perfusion in a swine model with hypercholesterolemia and chronic myocardial ischemia. Methods and Results Yorkshire swine fed a high cholesterol diet for 4 weeks underwent surgical placement of an ameroid constrictor to their left circumflex coronary artery. Three weeks later, animals received either: no drug, high cholesterol control group (HCC; n= 8); low dose CI (0.12 mg/kg; LCI, n= 9); or high dose CI (0.25 mg/kg; HCI, n= 8). The heart was harvested after 5 weeks. There was a trend toward increased right to left collateral vessels on angiography with HCI. Myocardial perfusion in ischemic myocardium significantly improved with HCI at rest and with demand pacing (p = 0.016 and 0.011). Endothelium-dependent microvessel relaxation was significantly improved with LCI (p = 0.001). There was a significant increase in capillary density, with LCI and HCI (p= 0.01 and 0.01), and arteriolar density with LCI (p= 0.001). CI significantly increased several proangiogenic proteins including VEGF (p= 0.02), VEGFR1 (p= 0.003), VEGFR2 (p= 0.003) and talin, a microvascular structural protein (p= 0.0002). There was a slight increase in proteins implicated in endothelial-dependent (NO Mediated) relaxation including ERK, p-ERK and iNOS with CI. Conclusions In the setting of hypercholesterolemia, CI improved perfusion, with a trend toward increased collateralization on angiography and increased capillary and arteriolar densities in ischemic myocardium. CI also improved endothelium-dependent microvessel relaxation and increased expression of proteins implicated in angiogenesis and vasodilatation. PMID:26478238

  9. Dynamic change of collateral flow varying with distribution of regional blood flow in acute ischemic rat cortex

    NASA Astrophysics Data System (ADS)

    Wang, Zhen; Luo, Weihua; Zhou, Fangyuan; Li, Pengcheng; Luo, Qingming

    2012-12-01

    Cerebral blood flow (CBF) is critical for the maintenance of cerebral function by guaranteed constant oxygen and glucose supply to brain. Collateral channels (CCs) are recruited to provide alternatives to CBF to ischemic regions once the primary vessel is occluded during ischemic stroke. However, the knowledge of the relationship between dynamic evolution of collateral flow and the distribution of regional blood flow remains limited. In this study, laser speckle imaging was used to assess dynamic changes of CCs and regional blood flow in a rat cortex with permanent middle cerebral artery occlusion (MCAo). We found that CCs immediately provided blood flow to ischemic territories after MCAo. More importantly, there were three kinds of dynamic changes of CCs during acute stroke: persistent CC, impermanent CC, and transient CC, respectively, related to different distributions of regional blood flow. Although there was the possible occurrence of peri-infarct depolarization (PID) during ischemia, there was no obvious significance about the onset time and duration of CCs between rats with and without PID. These results suggest that the initial arising of CCs does not ensure their persistence, and that collateral flow could be varied with distribution of regional blood flow in acute ischemic stroke, which may facilitate the understanding of collateral recruitment and promote the development of collateral therapeutics in the future.

  10. Lateral collateral ligament reconstruction for chronic varus instability of the hallux interphalangeal joint.

    PubMed

    Cho, Jaeho

    2014-01-01

    Chronic varus instability of the hallux interphalangeal joint is a rare injury, and only a few reports of this injury have been published. In some studies, this injury has been related to taekwondo. Taekwondo is an essential martial art in the Korean military. We have described a case of varus instability of the hallux interphalangeal joint in a professional soldier who had practiced taekwondo for 5 years and the surgical outcome after reconstruction of the lateral collateral ligament with the fourth toe extensor tendon.

  11. Post traumatic osteoma of tibial insertion of medial collateral ligament of knee joint

    PubMed Central

    Shanker, V. S.; Gadikoppula, S.; Loeffler, M. D.

    1998-01-01

    Two cases are presented of post traumatic para-articular osteoma developing at the site of tibial attachment of the medial collateral ligament of knee joint. These occurred after injuries sustained while playing football and in one case the ossified mass was treated with surgical excision for unresolved symptoms after conservative measures. A comparison is made with Pellegrini Stieda disease, which is a similar affection of the femoral insertion of the medial ligament of the knee joint. 




 PMID:9562171

  12. Collateral damage-free debridement using 193nm ArF laser

    NASA Astrophysics Data System (ADS)

    Wynne, James J.; Felsenstein, Jerome M.; Trzcinski, Robert; Zupanski-Nielsen, Donna; Connors, Daniel P.

    2011-03-01

    Burn eschar and other necrotic areas of the skin and soft tissue are anhydrous compared to the underlying viable tissue. A 193 nm ArF excimer laser, emitting electromagnetic radiation at 6.4 eV at fluence exceeding the ablation threshold, will debride such necrotic areas. Because such radiation is strongly absorbed by aqueous chloride ions through the nonthermal process of electron photodetachment, debridement will cease when hydrated (with chloride ions) viable tissue is exposed, avoiding collateral damage to this tissue. Such tissue will be sterile and ready for further treatment, such as a wound dressing and/or a skin graft.

  13. Science from Kepler Collateral Data: 50 Kilosecond per Year from 13 Million Star?

    NASA Technical Reports Server (NTRS)

    Kolodziejczak, J. J.; Caldwell, D. A.

    2011-01-01

    As each Kepler frame is read out, light from each star in a CCD column accumulates in successive pixels as they wait for the next row to be read out. This accumulation is the same in the masked rows at the start of the readout and virtual rows at the end of the readout as it is in the science data. A range of these "smear" rows are added together for each long cadence and sent to the ground for calibration purposes. We will introduce and describe this smear collateral data, discuss and demonstrate its potential use for scientific studies exclusive of Kepler calibration,.

  14. The Association between Whole Blood Viscosity and Coronary Collateral Circulation in Patients with Chronic Total Occlusion

    PubMed Central

    Ozcan Cetin, Elif Hande; Balcı, Kevser Gülcihan; Aydin, Selahattin; Ediboglu, Emek; Bayraktar, Muhammed Fatih; Balcı, Mustafa Mücahit; Maden, Orhan; Temizhan, Ahmet; Aydogdu, Sinan

    2016-01-01

    Background and Objectives Coronary collateral circulation (CCC) has been attributed as inborn bypass mechanisms supporting ischemic myocardium. Various factors have been postulated in CCC. Whole blood viscosity (WBV) has been an underappreciated entity despite close relationships between multiple cardiovascular diseases. WBV can be calculated with a validated equation from hematocrit and total plasma protein levels for a low and high shear rate. On the grounds, we aimed to evaluate the association between WBV and CCC in patients with chronic total occlusion. Subjects and Methods A total of 371 patients diagnosed as having at least one major, chronic total occluded coronary artery were included. 197 patients with good CCC (Rentrop 2 and 3) composed the patient group. The poor collateral group consisted of 174 patients (Rentrop grade 0 and 1). Results Patients with poor CCC had higher WBV values for a low-shear rate (LSR) (69.5±8.7 vs. 60.1±9.8, p<0.001) and high-shear rate (HSR) (17.0±2.0 vs. 16.4±1.8, p<0.001) than the good collateral group. Correlation analysis demonstrated a significant negative correlation between the grade of CCC and WBV for LSR (β=0.597, p<0.001) and HSR (β=0.494, p<0.001). WBV for LSR (β=0.476, p<0.001) and HSR (β=0.407, p<0.001) had a significant correlation with the synergy between percutaneous coronary intervention with taxus and cardiac surgery (SYNTAX) score. A multivariate analysis showed that the WBV for both shear rates were independent risk factors of poor CCC (WBV at LSR, OR: 1.362 CI 95%: 1.095-1.741 p<0.001 and WBV at HSR, 1.251 CI 95%: 1.180-1.347 p<0.001). Conclusion WBV has been demonstrated as the overlooked predictor of poor coronary collateralization. WBV seemed to be associated with microvascular perfusion and angiogenesis process impairing CCC development. PMID:27826336

  15. A Technique of Superficial Medial Collateral Ligament Reconstruction Using an Adjustable-Loop Suspensory Fixation Device.

    PubMed

    Deo, Shaneel; Getgood, Alan

    2015-06-01

    This report describes superficial medial collateral ligament reconstruction of the knee using a novel method of graft fixation with the ACL Tightrope RT (Arthrex, Naples, FL). After tibial fixation with either a standard interference screw or staple, femoral fixation of the semitendinosus tendon is performed with the adjustable-loop suspensory fixation device, which allows for both initial graft tensioning and re-tensioning after cyclical knee range of motion. This provides the ability for the graft to accommodate for resultant soft-tissue creep and stress relaxation, thereby allowing for optimal soft-tissue tension and reduction in laxity at the end of the procedure.

  16. Rupture of the ulnar collateral ligament of the thumb – a review

    PubMed Central

    2013-01-01

    Skier’s thumb is a partial or complete rupture of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb. It is an often-encountered injury and can lead to chronic pain and instability when diagnosed incorrectly. Knowledge of the anatomy and accurate physical examination are essential in the evaluation of a patient with skier’s thumb. This article provides a review of the relevant anatomy, the correct method of physical examination and the options for additional imaging and treatment with attention to possible pitfalls. PMID:23938194

  17. Rupture of the ulnar collateral ligament of the thumb - a review.

    PubMed

    Mahajan, Mandhkani; Rhemrev, Steven J

    2013-08-12

    Skier's thumb is a partial or complete rupture of the ulnar collateral ligament of the metacarpophalangeal joint of the thumb. It is an often-encountered injury and can lead to chronic pain and instability when diagnosed incorrectly. Knowledge of the anatomy and accurate physical examination are essential in the evaluation of a patient with skier's thumb. This article provides a review of the relevant anatomy, the correct method of physical examination and the options for additional imaging and treatment with attention to possible pitfalls.

  18. Elbow ulnar collateral ligament injuries in athletes: Can we improve our outcomes?

    PubMed Central

    Redler, Lauren H; Degen, Ryan M; McDonald, Lucas S; Altchek, David W; Dines, Joshua S

    2016-01-01

    Injury to the ulnar collateral ligament (UCL) most commonly occurs in the overhead throwing athlete. Knowledge surrounding UCL injury pathomechanics continues to improve, leading to better preventative treatment strategies and rehabilitation programs. Conservative treatment strategies for partial injuries, improved operative techniques for reconstruction in complete tears, adjunctive treatments, as well as structured sport specific rehabilitation programs including resistive exercises for the entire upper extremity kinetic chain are all important factors in allowing for a return to throwing in competitive environments. In this review, we explore each of these factors and provide recommendations based on the available literature to improve outcomes in UCL injuries in athletes. PMID:27114930

  19. Pulmonary atresia and ventricular septal defect with aortopulmonary collaterals in an adult dog.

    PubMed

    Tou, Sandra P; Keene, Bruce W; Barker, Piers C A

    2011-12-01

    Pulmonary atresia and ventricular septal defect (PA-VSD) was diagnosed in a 2-year-old castrated male Terrier mix. Transthoracic echocardiography identified a large ventricular septal defect, overriding aorta and severe right ventricular hypertrophy. A main pulmonary artery could not be identified, consistent with pulmonary atresia or persistent truncus arteriosus. Transesophageal echocardiography and angiography confirmed PA-VSD with aortopulmonary collateral circulation arising from the descending thoracic aorta. This case report describes the antemortem diagnosis of the rare congenital defect PA-VSD in an adult dog.

  20. New branches of massive gravity

    NASA Astrophysics Data System (ADS)

    Comelli, D.; Crisostomi, M.; Koyama, K.; Pilo, L.; Tasinato, G.

    2015-06-01

    The basic building block for Lorentz-invariant and ghost-free massive gravity is the square root of the combination g-1η , where g-1 is the inverse of the physical metric and η is a reference metric. Since the square root of a matrix is not uniquely defined, it is possible to have physically inequivalent potentials corresponding to different branches. We show that around the Minkowski background, the only perturbatively well-defined branch is the potential proposed by de Rham, Gabadadze and Tolley. On the other hand, if Lorentz symmetry is broken spontaneously, other potentials exist with a standard perturbative expansion. We show this explicitly building new Lorentz-invariant, ghost-free massive gravity potentials for theories that in the background preserve rotational invariance but break Lorentz boosts.

  1. Geodynamics Branch research report, 1982

    NASA Technical Reports Server (NTRS)

    Kahn, W. D. (Editor); Cohen, S. C. (Editor)

    1983-01-01

    The research program of the Geodynamics Branch is summarized. The research activities cover a broad spectrum of geoscience disciplines including space geodesy, geopotential field modeling, tectonophysics, and dynamic oceanography. The NASA programs which are supported by the work described include the Geodynamics and Ocean Programs, the Crustal Dynamics Project, the proposed Ocean Topography Experiment (TOPEX) and Geopotential Research Mission. The individual papers are grouped into chapters on Crustal Movements, Global Earth Dynamics, Gravity Field Model Development, Sea Surface Topography, and Advanced Studies.

  2. Horizontal-branch stellar evolution

    NASA Technical Reports Server (NTRS)

    Sweigart, Allen V.

    1990-01-01

    The results of canonical theory for the evolution of horizontal-branch (HB) stars are examined. Particular attention is given to how an HB star maintains the appropriate composition distribution within the semiconvective zone and how this composition is affected by the finite time-dependence with which convective boundaries actually move. Newly developed models based on time-dependent overshooting are presented for both the core-helium-exhaustion and main HB phases.

  3. Solid State Photovoltaic Research Branch

    SciTech Connect

    Not Available

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  4. Walker Branch Watershed Ecosystems Data

    DOE Data Explorer

    Walker Branch Watershed is located on the U. S. Department of Energy's Oak Ridge Reservation near Oak Ridge, in Anderson County, Tennessee. The Walker Branch Watershed Project began in 1967 under sponsorship of the U. S. Atomic Energy Commission (now the U. S. Department of Energy). Initially, the project centered primarily on the geologic and hydrologic processes that control the amounts and chemistry of water moving through the watershed. Past projects have included: • U. S. Department of Energy funded studies of watershed hydrology and forest nutrient dynamics • National Oceanic and Atmospheric Administration funded studies of forest micrometeorology • Studies of atmospheric deposition under the National Atmospheric Deposition Program • The International Biological Program Eastern Deciduous Forest Biome Project • National Science Foundation sponsored studies of trace element cycling and stream nutrient spiraling • Electric Power Research Institute funded studies of the effects of acidic deposition on canopy processes and soil chemistry. These projects have all contributed to a more complete understanding of how forest watersheds function and have provided insights into the solution of energy-related problems associated with air pollution, contaminant transport, and forest nutrient dynamics. This is one of a few sites in the world characterized by long-term, intensive environmental studies. The Walker Branch Watershed website at http://walkerbranch.ornl.gov/ provides maps, photographs, and data on climate, precipitation, atmospheric deposition, stream discharge and runoff, stream chemistry, and vegetation. [Taken from http://walkerbranch.ornl.gov/ABOUTAAA.HTM

  5. Collateral Damage

    DTIC Science & Technology

    1978-10-01

    prev-ntion of burns (except while swimming, at nudist camps, etc.). Large-area burns which con- tribute directly to letha’ity must be produced under...0 0)V -44-4 0 to *9: j ej 0 r 0 =4-) I I I I--a C - C"O -• -. tot Aanf0 0 30 (atjjqvqoi. 7-37 " •,•; o t " • 0 0. .. 4IU(W4co 0.0 0 -60~ 2~. .) 041

  6. Managing occurrence branching in qualitative simulation

    SciTech Connect

    Tokuda, L.

    1996-12-31

    Qualitative simulators can produce common sense abstractions of complex behaviors given only partial knowledge about a system. One of the problems which limits the applicability of qualitative simulators is the intractable branching of successor states encountered with model of even modest size. Some branches may be unavoidable due to the complex nature of a system. Other branches may be accidental results of the model chosen. A common source of intractability is occurrence branching. Occurrence branching occurs when the state transitions of two variables are unordered with respect to each other. This paper extends the QSIM model to distinguish between interesting occurrence branching and uninteresting occurrence branching. A representation, algorithm, and simulator for efficiently handling uninteresting branching is presented.

  7. Formation of Collateral Veins in a Graft Pancreas After a Simultaneous Pancreas and Kidney Transplantation: A Case Report.

    PubMed

    Choi, B H; Lee, H Y; Park, Y M; Yang, K H; Ryu, J H; Chu, C W

    2015-09-01

    A graft vein thrombosis is the main cause of early graft failure after pancreas transplantation. We report a case of formation of collateral veins in a graft pancreas after transplant. A 30-year-old woman underwent simultaneous pancreas and kidney transplantation. She was discharged 16 days after the operation with good pancreas and kidney function. A total occlusion of the portal vein was discovered on computed tomography (CT) performed at an outpatient clinic. She had no symptoms or signs of hyperglycemia. Venography was attempted for vein thrombectomy but failed. After 2 weeks of heparinization therapy, the edema disappeared and perfusion of the graft pancreas improved. However, the thrombotic occlusion was not resolved on CT. Arteriography of the Y-graft revealed collateral veins. She was discharged with warfarin. She is currently doing well without any symptoms or signs. This is the first reported case of collateral vein formation in a grafted pancreas after pancreas transplantation.

  8. Inhibition of collateral artery growth by mibefradil: possible role of volume-regulated chloride channels.

    PubMed

    Ziegelhoeffer, Tibor; Scholz, Dimitri; Friedrich, Christian; Helisch, Armin; Wagner, Shawn; Fernandez, Borja; Schaper, Wolfgang

    2003-01-01

    Endothelial cell swelling is one of the earliest hallmarks of arteriogenesis, the growth and maturation of collaterals. Mibefradil was found to block endothelial Cl(-) channels that control the volume of endothelial cells. Thus the authors investigated whether the blockade of volume-controlling endothelial cell channels would translate into an inhibition of arteriogenesis. In BALB/c mice, the right femoral artery was ligated and the animals received either mibefradil or solvent (phosphate-buffered saline [PBS]) via osmotic minipumps. Laser Doppler perfusion ratio (R/L) of ligated versus nonligated distal hindlimb increased from 0.06 +/- 0.01 (immediately after ligation) to 0.25 +/- 0.02 (day 7) in the PBS group and only from 0.07 +/- 0.02 to 0.13 +/- 0.02 in the mibefradil group (p <.01). Collateral artery diameters were significantly smaller in the mibefradil group (61 +/- 4.7 microm) versus controls (77.3 +/- 0.9 microm) (p <.05). Relative hemoglobin oxygen saturation measurements confirmed these findings (p <.02). The inhibition of arteriogenesis in the mibefradil group suggests that endothelial Cl(-) channels are involved in the initiation of arteriogenesis.

  9. Traversing and dilating venous collaterals: a useful adjunct in left ventricular electrode placement.

    PubMed

    Abben, Richard P; Chaisson, Gary; Nair, Vinod

    2010-06-01

    In patients receiving cardiac resynchronization therapy (CRT), the left ventricular electrode cannot always be positioned in the preferred lateral or posterolateral locations due to technical factors and anatomic variations in the coronary sinus. Recent reports also suggest that CRT outcomes are improved by pacing the site of latest dyssynchrony and accessing these regions is not always possible. We report the utility of applying a technique described in the interventional literature over the past 3 years, effectively traversing and dilating collateral channels. Our patients demonstrated either no venous targets in the optimal location, or problems accessing this location using a antegrade approach. Subsequently, collaterals supplying this region were traversed with a guidewire using a retrograde approach and dilated with a balloon catheter. In the first case, the pacing electrode was then advanced in similar fashion and successfully positioned in an ideal lateral location. In the second case, the retrograde guidewire was captured with a vascular snare and pulled into a second guiding catheter, allowing appropriate dilatation and stenting of a problematic proximal venous stenosis with resultant facile placement of the pacing electrode. This technique offers a potential alternative to patients with challenging venous anatomy as a method to facilitate optimal CRT outcomes.

  10. Dopaminergic modulation of axon collaterals interconnecting spiny neurons of the rat striatum.

    PubMed

    Guzmán, Jaime N; Hernández, Adán; Galarraga, Elvira; Tapia, Dagoberto; Laville, Antonio; Vergara, Ramiro; Aceves, Jorge; Bargas, José

    2003-10-01

    Dopamine is a critical modulator of striatal function; its absence produces Parkinson's disease. Most cellular actions of dopamine are still unknown. This work describes the presynaptic actions of dopaminergic receptor agonists on GABAergic transmission between neostriatal projection neurons. Axon collaterals interconnect projection neurons, the main axons of which project to other basal ganglia nuclei. Most if not all of these projecting axons pass through the globus pallidus. Thus, we lesioned the intrinsic neurons of the globus pallidus and stimulated neostriatal efferent axons antidromically with a bipolar electrode located in this nucleus. This maneuver revealed a bicuculline-sensitive synaptic current while recording in spiny cells. D1 receptor agonists facilitated whereas D2 receptor agonists depressed this synaptic current. In contrast, a bicuculline-sensitive synaptic current evoked by field stimulation inside the neostriatum was not consistently modulated, in agreement with previous studies. The data are discussed in light of the most recent experimental and modeling results. The conclusion was that inhibition of spiny cells by axon collaterals of other spiny cells is quantitatively important; however, to be functionally important, this inhibition might be conditioned to the synchronized firing of spiny neurons. Finally, dopamine exerts a potentially important role regulating the extent of lateral inhibition.

  11. Shear induced collateral artery growth modulated by endoglin but not by ALK1

    PubMed Central

    Seghers, Leonard; de Vries, Margreet R; Pardali, Evangelia; Hoefer, Imo E; Hierck, Beerend P; ten Dijke, Peter ten; Goumans, Marie Jose; Quax, Paul HA

    2012-01-01

    Transforming growth factor-beta (TGF-β) stimulates both ischaemia induced angiogenesis and shear stress induced arteriogenesis by signalling through different receptors. How these receptors are involved in both these processes of blood flow recovery is not entirely clear. In this study the role of TGF-β receptors 1 and endoglin is assessed in neovascularization in mice. Unilateral femoral artery ligation was performed in mice heterozygous for either endoglin or ALK1 and in littermate controls. Compared with littermate controls, blood flow recovery, monitored by laser Doppler perfusion imaging, was significantly hampered by maximal 40% in endoglin heterozygous mice and by maximal 49% in ALK1 heterozygous mice. Collateral artery size was significantly reduced in endoglin heterozygous mice compared with controls but not in ALK1 heterozygous mice. Capillary density in ischaemic calf muscles was unaffected, but capillaries from endoglin and ALK1 heterozygous mice were significantly larger when compared with controls. To provide mechanistic evidence for the differential role of endoglin and ALK1 in shear induced or ischaemia induced neovascularization, murine endothelial cells were exposed to shear stress in vitro. This induced increased levels of endoglin mRNA but not ALK1. In this study it is demonstrated that both endoglin and ALK1 facilitate blood flow recovery. Importantly, endoglin contributes to both shear induced collateral artery growth and to ischaemia induced angiogenesis, whereas ALK1 is only involved in ischaemia induced angiogenesis. PMID:22436015

  12. Rotational stability test for the diagnosis of radial collateral ligament rupture in the fingers: Anatomical study.

    PubMed

    Lazarus, P; Hidalgo Diaz, J J; Prunières, G; Pire, E; Taleb, C; Honecker, S; Bellemère, P; Fontaine, C; Liverneaux, P A

    2017-04-01

    Diagnosing rupture of the radial collateral ligament (RCL) of the finger metacarpophalangeal (MCP) joints is difficult. The aim of this cadaver study was to validate a rotational test for the MCP after RCL transection. With the MCP and proximal interphalangeal joints in flexion, rotation along the axis of the proximal phalanx was applied through an extended distal interphalangeal joint to 36 cadaver fingers. Each finger's pulp described an arc of pronation and supination that was noted on the palm. The test was repeated three times: before transection, after transection of the proper collateral ligament (CL) and after transection of both the proper and accessory CLs. Rotational arcs were measured in pronation and supination. Mean length of the pronation arc after transection of the main RCL was 17.53mm, while it was only 12.41mm before transection for the supination arc. Mean length of the pronation arc after transection of both CLs was 22.83mm compared to only 11.93mm before transection. Our results show a significant difference in pronation stability of the MCP joint after transection of the RCL proper. We can conclude that this rotational stability test is a valid test for diagnosing RCL rupture in MCP joints.

  13. Synergistic, collaterally sensitive β-lactam combinations suppress resistance in MRSA

    PubMed Central

    Gonzales, Patrick R.; Pesesky, Mitchell W.; Bouley, Renee; Ballard, Anna; Biddy, Brent A.; Suckow, Mark A.; Wolter, William R.; Schroeder, Valerie A.; Burnham, Carey-Ann D.; Mobashery, Shahriar; Chang, Mayland; Dantas, Gautam

    2015-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most prevalent multidrug-resistant pathogens worldwide, exhibiting increasing resistance to the latest antibiotic therapies. Here we show that the triple β-lactam combination meropenem/piperacillin/tazobactam (ME/PI/TZ) acts synergistically and is bactericidal against MRSA N315 and 72 clinical MRSA isolates in vitro, and clears MRSA N315 infection in a mouse model. ME/PI/TZ suppresses evolution of resistance in MRSA via reciprocal collateral sensitivity of its constituents. We demonstrate that these activities also extend to other carbapenem/penicillin/β-lactamase inhibitor combinations. ME/PI/TZ circumvents the tight regulation of the mec and bla operons in MRSA, the basis for inducible resistance to β-lactam antibiotics. Furthermore, ME/PI/TZ subverts the function of penicillin-binding protein 2a (PBP2a) action via allostery, which we propose as the mechanism for both synergy and collateral sensitivity. Showing similar in vivo activity to linezolid, ME/PI/TZ demonstrates that combinations of older β-lactam antibiotics could be effective against MRSA infections in humans. PMID:26368589

  14. Myeloperoxidase targets oxidative host attacks to Salmonella and prevents collateral tissue damage.

    PubMed

    Schürmann, Nura; Forrer, Pascal; Casse, Olivier; Li, Jiagui; Felmy, Boas; Burgener, Anne-Valérie; Ehrenfeuchter, Nikolaus; Hardt, Wolf-Dietrich; Recher, Mike; Hess, Christoph; Tschan-Plessl, Astrid; Khanna, Nina; Bumann, Dirk

    2017-01-23

    Host control of infections crucially depends on the capability to kill pathogens with reactive oxygen species (ROS). However, these toxic molecules can also readily damage host components and cause severe immunopathology. Here, we show that neutrophils use their most abundant granule protein, myeloperoxidase, to target ROS specifically to pathogens while minimizing collateral tissue damage. A computational model predicted that myeloperoxidase efficiently scavenges diffusible H2O2 at the surface of phagosomal Salmonella and converts it into highly reactive HOCl (bleach), which rapidly damages biomolecules within a radius of less than 0.1 μm. Myeloperoxidase-deficient neutrophils were predicted to accumulate large quantities of H2O2 that still effectively kill Salmonella, but most H2O2 would leak from the phagosome. Salmonella stimulation of neutrophils from normal and myeloperoxidase-deficient human donors experimentally confirmed an inverse relationship between myeloperoxidase activity and extracellular H2O2 release. Myeloperoxidase-deficient mice infected with Salmonella had elevated hydrogen peroxide tissue levels and exacerbated oxidative damage of host lipids and DNA, despite almost normal Salmonella control. These data show that myeloperoxidase has a major function in mitigating collateral tissue damage during antimicrobial oxidative bursts, by converting diffusible long-lived H2O2 into highly reactive, microbicidal and locally confined HOCl at pathogen surfaces.

  15. The March of Extrahepatic Collaterals: Analysis of Blood Supply to Hepatocellular Carcinoma Located in the Bare Area of the Liver After Chemoembolization

    SciTech Connect

    Miyayama, Shiro Yamashiro, Masashi; Okuda, Miho; Yoshie, Yuichi; Nakashima, Yoshiko; Ikeno, Hiroshi; Orito, Nobuaki; Matsui, Osamu

    2010-06-15

    The purpose of this study was to evaluate changes in vascular supply to hepatocellular carcinoma (HCC) located in the bare area of the liver in patients who were mainly treated with chemoembolization. Twenty-six patients with HCC showing a mean diameter of 3.1 {+-} 1.4 cm (mean {+-} standard deviation) were mainly treated with chemoembolization. All patients underwent 2.7 {+-} 2.3 chemoembolization sessions over 40.1 {+-} 25.2 months. Tumor feeding branches demonstrated in each chemoembolization session were retrospectively evaluated. Initially, 18 tumors (59.2%) were supplied by the hepatic artery (H) and 8 (30.8%) by both the hepatic and the extrahepatic arteries (H + C). Fourteen tumors (53.8%) recurred at the posterior aspect of the tumor and were supplied by H (n = 4), H + C (n = 5), and extrahepatic collaterals (C) (n = 5). Several tumors recurred despite repeated chemoembolization, and these were supplied by H (n = 1), H + C (n = 7), and C (n = 2) at the second recurrence, by H (n = 1), H + C (n = 2), and C (n = 3) at the third, by H + C (n = 2) and C (n = 2) at the fourth, by H + C (n = 2) and C (n = 2) at the fifth, and by H (n = 1) and C (n = 1) at the sixth. One tumor was supplied by H at the seventh and by H + C at the eighth recurrence. As the number of local recurrences increased, the feeding vessel shifted from H to C. Especially, the right inferior phrenic artery (IPA) and renal capsular artery (RCA) supplied the tumor early, while the small right RCAs, adrenal arteries, and intercostal and lumbar artery supplied late recurrences in turns. In conclusion, HCCs located in the bare area are frequently supplied by extrahepatic vessels initially, while recurrence after chemoembolization is mainly due to extrahepatic blood supply. The right IPA and RCA are common feeding vessels demonstrated early, while other extrahepatic collateral supply from the retroperitoneal circulation occurs in turns during the later course.

  16. Guide to the Seattle Archives Branch.

    ERIC Educational Resources Information Center

    Hobbs, Richard, Comp.

    The guide presents an overview of the textual and microfilmed records located at the Seattle Branch of the National Archives of the United States. Established in 1969, the Seattle Archives Branch is one of 11 branches which preserve and make available for research those U.S. Government records of permanent value created and maintained by Federal…

  17. Introduction of Branching Degrees of Octane Isomers.

    PubMed

    Perdih, Anton

    2016-01-01

    The concept of branching degrees is introduced. In the case of octane isomers it is derived from the values of a set of their physicochemical properties, calculating for each isomer the average of the normalized values and these averages are defined as branching degrees of octane isomers. The sequence of these branching degrees of octane isomers does not differ much from the »regular« one defined earlier. 2,2-Dimethylhexane appears to be less branched than 3,4-dimethylhexane and 3-ethyl, 2-methylpentane, whereas 2,3,4-trimethylpentane appears to be less branched than 3-ethyl, 3-methylpentane. While the increasing number of branches gives rise to increasing branching degrees, the peripheral position of branches and the separation between branches decreases the value of the branching degree. The central position of branches increases it. A bigger branch increases it more than a smaller one. The quantification of these structural features and their correlations with few indices is given as well.

  18. Structural dynamics branch research and accomplishments

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Summaries are presented of fiscal year 1989 research highlights from the Structural Dynamics Branch at NASA Lewis Research Center. Highlights from the branch's major work areas include aeroelasticity, vibration control, dynamic systems, and computation structural methods. A listing of the fiscal year 1989 branch publications is given.

  19. In vivo single branch axotomy induces GAP-43–dependent sprouting and synaptic remodeling in cerebellar cortex

    PubMed Central

    Allegra Mascaro, Anna Letizia; Cesare, Paolo; Sacconi, Leonardo; Grasselli, Giorgio; Mandolesi, Georgia; Maco, Bohumil; Knott, Graham W.; Huang, Lieven; De Paola, Vincenzo; Strata, Piergiorgio; Pavone, Francesco S.

    2013-01-01

    Plasticity in the central nervous system in response to injury is a complex process involving axonal remodeling regulated by specific molecular pathways. Here, we dissected the role of growth-associated protein 43 (GAP-43; also known as neuromodulin and B-50) in axonal structural plasticity by using, as a model, climbing fibers. Single axonal branches were dissected by laser axotomy, avoiding collateral damage to the adjacent dendrite and the formation of a persistent glial scar. Despite the very small denervated area, the injured axons consistently reshape the connectivity with surrounding neurons. At the same time, adult climbing fibers react by sprouting new branches through the intact surroundings. Newly formed branches presented varicosities, suggesting that new axons were more than just exploratory sprouts. Correlative light and electron microscopy reveals that the sprouted branch contains large numbers of vesicles, with varicosities in the close vicinity of Purkinje dendrites. By using an RNA interference approach, we found that downregulating GAP-43 causes a significant increase in the turnover of presynaptic boutons. In addition, silencing hampers the generation of reactive sprouts. Our findings show the requirement of GAP-43 in sustaining synaptic stability and promoting the initiation of axonal regrowth. PMID:23754371

  20. Side-Branch and Coaxial Intravascular Ultrasound Guided Wire Re-Entry after Failed Retrograde Approach of Chronic Total Occlusion Intervention

    PubMed Central

    Chou, Ruey-Hsing; Lai, Chih-Hung; Lu, Tse-Min

    2016-01-01

    Intravascular ultrasound (IVUS) can provide valuable information during the intervention of difficult chronic total occlusion (CTO) lesion. Stumpless CTO lesions with an adjacent side branch are associated with a significantly lower success rate because the proper entry point is not always clearly identified and the guidewires easily slip into the side branch. Herein we presented a case of a stumpless middle left circumflex (LCX) artery CTO lesion with auto-collateral from obtuse marginal branch. Initially, we positioned the IVUS into the side-branch to find the entry point of LCX-CTO lesion. However, the punctured wire went into the false lumen. A retrograde approach was tried but later failed. Therefore, we used IVUS to find the entry point where the true lumen transited to the false lumen, and used a stiff guidewire to puncture the entry point. After we confirmed with IVUS that the whole guidewire was in the true lumen, we deployed 3 drug-eluting stents. The final angiogram showed TIMI 3 flow with preservation of all side branches. The patient was angina-free during the 6-month follow-up. By presenting this case, we have demonstrated the application of both side-branch and coaxial IVUS-guided recanalization technique in the stumpless CTO lesion. PMID:27274179

  1. S-branch CARS applicability to thermometry

    SciTech Connect

    Akihama, K.; Asai, T. )

    1990-07-20

    The pressure and temperature dependence of background-free {ital S}-branch CARS spectra of N{sub 2} are investigated in the temperature range of 300--700 K for pressures of 1--20 atm. Collisional narrowing for {ital S}-branch CARS spectra is proved to be negligible. Individual {ital S}-branch lines are clearly resolved in the entire range, enabling unequivocal determination of temperatures by their peak ratios. Advantages and disadvantages of {ital S}-branch CARS thermometry are discussed on the basis of experimental results. The dual narrowband Stokes CARS technique is also discussed as a practical method of {ital S}-branch CARS thermometry.

  2. S-branch CARS applicability to thermometry.

    PubMed

    Akihama, K; Asai, T

    1990-07-20

    The pressure and temperature dependence of background-free S-branch CARS spectra of N(2) are investigated in the temperature range of 300-700 K for pressures of 1-20 atm. Collisional narrowing for S-branch CARS spectra is proved to be negligible. Individual S-branch lines are clearly resolved in the entire range, enabling unequivocal determination of temperatures by their peak ratios. Advantages and disadvantages of S-branch CARS thermometry are discussed on the basis of experimental results. The dual narrowband Stokes CARS technique is also discussed as a practical method of S-branch CARS thermometry.

  3. Evolutionary branching under slow directional evolution.

    PubMed

    Ito, Hiroshi C; Dieckmann, Ulf

    2014-11-07

    Evolutionary branching is the process by which ecological interactions induce evolutionary diversification. In asexual populations with sufficiently rare mutations, evolutionary branching occurs through trait-substitution sequences caused by the sequential invasion of successful mutants. A necessary and sufficient condition for evolutionary branching of univariate traits is the existence of a convergence stable trait value at which selection is locally disruptive. Real populations, however, undergo simultaneous evolution in multiple traits. Here we extend conditions for evolutionary branching to bivariate trait spaces in which the response to disruptive selection on one trait can be suppressed by directional selection on another trait. To obtain analytical results, we study trait-substitution sequences formed by invasions that possess maximum likelihood. By deriving a sufficient condition for evolutionary branching of bivariate traits along such maximum-likelihood-invasion paths (MLIPs), we demonstrate the existence of a threshold ratio specifying how much disruptive selection in one trait direction is needed to overcome the obstruction of evolutionary branching caused by directional selection in the other trait direction. Generalizing this finding, we show that evolutionary branching of bivariate traits can occur along evolutionary-branching lines on which residual directional selection is sufficiently weak. We then present numerical analyses showing that our generalized condition for evolutionary branching is a good indicator of branching likelihood even when trait-substitution sequences do not follow MLIPs and when mutations are not rare. Finally, we extend the derived conditions for evolutionary branching to multivariate trait spaces.

  4. Growth of branched actin networks against obstacles.

    PubMed Central

    Carlsson, A E

    2001-01-01

    A method for simulating the growth of branched actin networks against obstacles has been developed. The method is based on simple stochastic events, including addition or removal of monomers at filament ends, capping of filament ends, nucleation of branches from existing filaments, and detachment of branches; the network structure for several different models of the branching process has also been studied. The models differ with regard to their inclusion of effects such as preferred branch orientations, filament uncapping at the obstacle, and preferential branching at filament ends. The actin ultrastructure near the membrane in lamellipodia is reasonably well produced if preferential branching in the direction of the obstacle or barbed-end uncapping effects are included. Uncapping effects cause the structures to have a few very long filaments that are similar to those seen in pathogen-induced "actin tails." The dependence of the growth velocity, branch spacing, and network density on the rate parameters for the various processes is quite different among the branching models. An analytic theory of the growth velocity and branch spacing of the network is described. Experiments are suggested that could distinguish among some of the branching models. PMID:11566765

  5. Chiral methyl-branched pheromones.

    PubMed

    Ando, Tetsu; Yamakawa, Rei

    2015-07-01

    Insect pheromones are some of the most interesting natural products because they are utilized for interspecific communication between various insects, such as beetles, moths, ants, and cockroaches. A large number of compounds of many kinds have been identified as pheromone components, reflecting the diversity of insect species. While this review deals only with chiral methyl-branched pheromones, the chemical structures of more than one hundred non-terpene compounds have been determined by applying excellent analytical techniques. Furthermore, their stereoselective syntheses have been achieved by employing trustworthy chiral sources and ingenious enantioselective reactions. The information has been reviewed here not only to make them available for new research but also to understand the characteristic chemical structures of the chiral pheromones. Since biosynthetic studies are still limited, it might be meaningful to examine whether the structures, particularly the positions and configurations of the branched methyl groups, are correlated with the taxonomy of the pheromone producers and also with the function of the pheromones in communication systems.

  6. Incidence and predictors for the development of significant supradiaphragmatic decompressing venous collateral channels following creation of Fontan physiology.

    PubMed

    Weber, H S

    2001-05-01

    The occurrence of supradiaphragmatic decompressing venous collateral channels following construction of a bidirectional cavopulmonary connection or completion of the Fontan operation resulting in abnormal systemic hypoxemia has been infrequently described. In addition, the incidence and predictors of these channels have not been well delineated, especially in those patients without formation of such structures preoperatively. I evaluated, retrospectively, 40 patients who had undergone either construction of a bidirectional cavopulmonary shunt or completion of the Fontan operation, and who had complete pre and postoperative hemodynamic and angiographic data. Of the patients, 17 (43%) had developed a total of 21 decompressing venous collateral channels, of which 7 (18%) were considered to be hemodynamically significant requiring transcatheter coil occlusion. Of all variables examined, seven patients with significant decompressing collaterals had a greater transpulmonary gradient at follow-up catheterization (8 +/- 2 vs 5 +/- 2 mmHg, p=.01) and lower systemic saturations at routine clinical follow-up visits (82 +/- 5 vs 89 +/- 5 mmHg, p =.007) in comparison to the 33 others. When not evident preoperatively, decompressing venous collateral channels develop in a significant number of patients following conversion to Fontan physiology. If sufficiently large, they may produce lower than expected systemic saturations for the observed cardiac physiology. The larger decompressing channels are more likely to occur when a greater transpulmonary gradient exists postoperatively, which may require cardiac catheterization and transcatheter coil occlusion.

  7. Somatic membrane potential and Kv1 channels control spike repolarization in cortical axon collaterals and presynaptic boutons.

    PubMed

    Foust, Amanda J; Yu, Yuguo; Popovic, Marko; Zecevic, Dejan; McCormick, David A

    2011-10-26

    The shape of action potentials invading presynaptic terminals, which can vary significantly from spike waveforms recorded at the soma, may critically influence the probability of synaptic neurotransmitter release. Revealing the conductances that determine spike shape in presynaptic boutons is important for understanding how changes in the electrochemical context in which a spike is generated, such as subthreshold depolarization spreading from the soma, can modulate synaptic strength. Utilizing recent improvements in the signal-to-noise ratio of voltage-sensitive dye imaging in mouse brain slices, we demonstrate that intracortical axon collaterals and en passant presynaptic terminals of layer 5 pyramidal cells exhibit a high density of Kv1 subunit-containing ion channels, which generate a slowly inactivating K(+) current critically important for spike repolarization in these compartments. Blockade of the current by low doses of 4-aminopyridine or α-dendrotoxin dramatically slows the falling phase of action potentials in axon collaterals and presynaptic boutons. Furthermore, subthreshold depolarization of the soma broadened action potentials in collaterals bearing presynaptic boutons, an effect abolished by blocking Kv1 channels with α-dendrotoxin. These results indicate that action potential-induced synaptic transmission may operate through a mix of analog-digital transmission owing to the properties of Kv1 channels in axon collaterals and presynaptic boutons.

  8. Editorial Commentary: Chondrocytes Trump Ligaments! Partial Release of the Medial Collateral Ligament During Knee Arthroscopy Protects Chondrocytes.

    PubMed

    Leland, J Martin

    2016-10-01

    With knee arthroscopy being the most common orthopaedic procedure performed in the United States, it is crucial to be able to access the entire knee without iatrogenic injury. Frequently orthopaedic surgeons encounter tight medial compartments, creating difficulty in accessing the posterior horn of the medial meniscus without damaging the articular cartilage. Partial release of the medial collateral ligament during knee arthroscopy protects chondrocytes.

  9. Investigating the Effectiveness of Collateral Information on Small-Sample Equating. Research Report. ETS RR-08-52

    ERIC Educational Resources Information Center

    Kim, Sooyeon; Linvingston, Samuel A.; Lewis, Charles

    2008-01-01

    This paper describes an empirical evaluation of a Bayesian procedure for equating scores on test forms taken by small numbers of examinees, using collateral information from the equating of other test forms. In this procedure, a separate Bayesian estimate is derived for the equated score at each raw-score level, making it unnecessary to specify a…

  10. Trauma resulting in hemarthrosis and long medial collateral ligament desmitis of the tarsocrural joint in a horse

    PubMed Central

    Tokateloff, Nathalie; Carmalt, James; Manning, Stephen

    2011-01-01

    A horse was initially diagnosed with hemarthrosis and desmitis of the long medial collateral ligament of the right tarsus and later developed prominent enthesiophytosis at the site of insertion of the ligament’s deep portion. Hemarthrosis due to intra- or peri-articular pathology can cause recurrent lameness, even without evident external trauma. PMID:22043073

  11. Endothelial-Specific EphA4 Negatively Regulates Native Pial Collateral Formation and Re-Perfusion following Hindlimb Ischemia

    PubMed Central

    Okyere, Benjamin; Giridhar, Kaavya; Hazy, Amanda; Chen, Miao; Keimig, David; Bielitz, Robert C.; Xie, Hehuang; He, Jia-Qiang; Huckle, William R.; Theus, Michelle H.

    2016-01-01

    Leptomeningeal anastomoses play a critical role in regulating vascular re-perfusion following obstruction, however, the mechanisms regulating their development remains under investingation. Our current findings indicate that EphA4 receptor is a novel negative regulator of collaterogenesis. We demonstrate that EphA4 is highly expressed on pial arteriole collaterals at post-natal day (P) 1 and 7, then significantly reduced by P21. Endothelial cell (EC)-specific loss of EphA4, EphA4f/f/Tie2::Cre (KO), resulted in an increase in the density but not diameter of pial collaterals compared to WT mice. ECs isolated from KO mice displayed a 3-fold increase in proliferation, enhanced migration, tube formation and elevated levels of phospho(p)-Akt compared to WT ECs. Attenuating p-Akt, using LY294002, reduced the proliferative and migration effects in the KO ECs. RNAseq analysis also revealed altered expression patterns for genes that regulate cell proliferation, vascular development, extracellular matrix and immune-mediate responses, namely MCP-1, MMP2 and angiopoietin-1. Lastly, we show that induction of hindlimb ischemia resulted in accelerated re-perfusion, collateral remodeling and reduced tissue necrosis in the absence of EC-specific EphA4 compared to WT mice. These findings demonstrate a novel role for EphA4 in the early development of the pial collateral network and suggests a role in regulating vascular remodeling after obstruction. PMID:27467069

  12. A Report on Using General-Case Programming to Teach Collateral Academic Skills to a Student in a Postsecondary Setting

    ERIC Educational Resources Information Center

    Chezan, Laura C.; Drasgow, Erik; Marshall, Kathleen J.

    2012-01-01

    The authors' purpose in this report is to examine the application of general-case programming to teach collateral academic skills to a student with pervasive developmental disorder-not otherwise specified (PDD-NOS) and with a mild intellectual disability who was attending college. The authors use data drawn from their work with Tom to explain and…

  13. Surgical strategy to minimize ischemia during trapping/resection of giant extracranial carotid artery aneurysm stratified by collateral evaluation

    PubMed Central

    Hongo, Hiroki; Inoue, Tomohiro; Tamura, Akira; Saito, Isamu

    2017-01-01

    Background: Extracranial carotid artery aneurysm (ECAA) is a rare clinical entity, and no standard treatment strategy has been established for this condition. Methods: Data from three patients who underwent surgical treatment of enlarging giant ECAAs were retrospectively reviewed. Based on the collateral status, as evaluated by preoperative digital subtraction angiography (DSA), surgical strategy was stratified into (1) high flow bypass followed by cervical ICA (internal carotid artery) ligation, when the collateral status was judged as poor/fair or (2) direct cervical repair with patch application after aneurysmal wall resection when the collateral status was judged as robust. Postoperative results were evaluated by magnetic resonance imaging (MRI). Results: Postoperative follow-up (day 0 to 1, as well as midterm at approximately 6 months) confirmed completely trapped aneurysm with successful robust bypass and robust anterograde flow of the reconstructed cervical carotid artery on magnetic resonance angiography with no additional ischemic lesions on diffusion weighted imaging and T2-weighted imaging when compared with preoperative imaging in all three patients. Postoperatively, there was no stroke event during the midterm follow-up at 6 months. Conclusions: Clinical results of ECAAs treated by a surgical strategy stratified based on collateral status, as evaluated by preoperative DSA, were favorable, without postoperative ischemic event, and with satisfactory mid-term MRI results. PMID:28303208

  14. 13 CFR 120.545 - What are SBA's policies concerning the liquidation of collateral and the sale of business loans...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false What are SBA's policies concerning the liquidation of collateral and the sale of business loans and physical disaster assistance loans, physical disaster business loans and economic injury disaster loans? 120.545 Section 120.545...

  15. 46 CFR 308.525 - Application for decrease in amount of cash collateral fund, Form MA-305.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Application for decrease in amount of cash collateral fund, Form MA-305. 308.525 Section 308.525 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk...

  16. 46 CFR 308.526 - Certificate for repayment of decrease of collateral deposit fund, Form MA-306.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Certificate for repayment of decrease of collateral deposit fund, Form MA-306. 308.526 Section 308.526 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Cargo Insurance Open Policy War Risk...

  17. [Explanation of essence and substance basis of channels and collaterals with fasciology].

    PubMed

    Wang, Jun; Wang, Chun-lei; Shen, Bao-lin; Yang, Lin-lin; Yuan, Lin

    2007-08-01

    In our research of digital human body, construct of image structures close to the recorder of human channels and collaterals, and trace back to development biology of connective tissue and process of organic evolution, and it is concluded that connective tissue bracket in human body may constitute a new functional system--human self-supervision and control system, meanwhile, we propose a new study field, fasciology. The significance is that it introduces a new functional system in human body and develops new field of scientific research; and it annotate biological foundation and therapeutic mechanisms of traditional Chinese medicine therapy, which provides medical biological foundation for modern channel research of traditional Chinese medicine; it proposes a suggestion for development strategy of traditional Chinese medicine.

  18. The ulnar collateral ligament of the human elbow joint. Anatomy, function and biomechanics.

    PubMed Central

    Fuss, F K

    1991-01-01

    The posterior portion of the ulnar collateral ligament, which arises from the posterior surface of the medial epicondyle, is taut in maximal flexion. The anterior portion, which takes its origin from the anterior and inferior surfaces of the epicondyle, contains three functional fibre bundles. One of these is taut in maximal extension, another in intermediate positions between middle position and full flexion while the third bundle is always taut and serves as a guiding bundle. Movements of the elbow joint are checked by the ligaments well before the bony processes forming the jaws of the trochlear notch lock into the corresponding fossae on the humerus. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:2050566

  19. [Science of Meridians, Collaterals and Acupoints--Exploration on teaching method of meridian syndromes].

    PubMed

    Wang, Yinping; Zhang, Zongquan; Wang, Wenlin; Yuan, Limin

    2015-04-01

    Meridian syndromes are the required basic knowledge for mastering Science of Meridians, Collaterals and Acupoints but have not brought the adequate attention on the teaching program. The writers discovered' that the content of this section occupied a decisive role for developing the students' clinical thinking ability and, stimulating their interests to learn classical TCM theories. It's necessary to enhance the importance on meridian syndromes during teaching program. The teaching program was discussed in three aspects, named workshop pattern, competitive pattern and multimedia pattern. This teaching method may improve students' interests in the study on classical TCM theories, deepen the understanding on knowledge and motivate students' learning autonomy so that the teaching quality can be improved.

  20. Arthroscopic trans-portal deep medial collateral ligament pie-crusting release.

    PubMed

    Atoun, Ehud; Debbi, Ronen; Lubovsky, Omri; Weiler, Andreas; Debbi, Eytan; Rath, Ehud

    2013-02-01

    Arthroscopic treatments of meniscal injuries of the knee are among the most common orthopaedic procedures performed. Adequate visualization of the posterior horn of the medial meniscus might be challenging, especially in patients with tight medial compartments. In these cases instrument manipulation in an attempt to reach the posterior horn of the meniscus can cause an iatrogenic chondral injury because of the narrow medial joint space. A transcutaneous medial collateral ligament (MCL) pie-crusting release facilitates expansion of the medial joint space in a case of a tight medial compartment. Nevertheless, it might cause injury to the superficial MCL, infection, and pain and injury to the saphenous nerve because of multiple needle punctures of the skin. We describe an inside-out, arthroscopic deep MCL pie-crusting release, which allows access to the medial meniscus through the anterior approach to provide good visualization of the footprint and sufficient working space.

  1. Retention of retinal axon collateral is responsible for induced ipsilateral retinotectal projections in adult goldfish.

    PubMed

    Sharma, S C; Tsai, C

    1991-01-01

    In normal goldfish, optic axons innervate only the contralateral optic tectum. When one eye was enucleated and the optic nerve of the other eye crushed, the regenerating optic axons innervated both optic tecta. We studied the presence of bilaterally projecting retinal ganglion cells by double retrograde cell labeling methods using Nuclear Yellow and True Blue dyes. About 10% of the retinal ganglion cells were double labeled and these cells were found throughout the retina. In addition, HRP application to the ipsilateral tectum revealed retrogradely-labeled retinal ganglion cells of all morphological types. These results suggest that induced ipsilateral projections are formed by regenerating axon collaterals and that all cell types are involved in the generation of normal mirror image typography.

  2. Suppression of ischemia in arterial occlusive disease by JNK-promoted native collateral artery development

    PubMed Central

    Ramo, Kasmir; Sugamura, Koichi; Craige, Siobhan; Keaney, John F; Davis, Roger J

    2016-01-01

    Arterial occlusive diseases are major causes of morbidity and mortality. Blood flow to the affected tissue must be restored quickly if viability and function are to be preserved. We report that disruption of the mixed-lineage protein kinase (MLK) - cJun NH2-terminal kinase (JNK) signaling pathway in endothelial cells causes severe blockade of blood flow and failure to recover in the murine femoral artery ligation model of hindlimb ischemia. We show that the MLK-JNK pathway is required for the formation of native collateral arteries that can restore circulation following arterial occlusion. Disruption of the MLK-JNK pathway causes decreased Dll4/Notch signaling, excessive sprouting angiogenesis, and defects in developmental vascular morphogenesis. Our analysis demonstrates that the MLK-JNK signaling pathway is a key regulatory mechanism that protects against ischemia in arterial occlusive disease. DOI: http://dx.doi.org/10.7554/eLife.18414.001 PMID:27504807

  3. Failure of cast immobilization for thumb ulnar collateral ligament avulsion fractures.

    PubMed

    Dinowitz, M; Trumble, T; Hanel, D; Vedder, N B; Gilbert, M

    1997-11-01

    To determine if small avulsion fractures of the thumb ulnar collateral ligament (UCL) with minimal (< or = 2.0 mm) displacement can successfully be treated by cast immobilization, the authors reviewed 9 patients with minimally displaced fractures initially treated by casting. Despite immobilization within an average of 2 days of the initial injury (range, 0-6 days), a minimum of 6 weeks of immobilization in a cast, and adequate rehabilitation, all 9 patients had persistent thumb pain, especially with activities requiring strong pinch. After undergoing open reduction and internal fixation, the patients had relief of thumb pain and pinch strength improved from 36% of the contralateral side to 89% (p < .01). Grip strength increased from 77% to 93% (p < .05), but the ranges of motion of the thumb metacarpophalangeal and interphalangeal joints were not significantly altered. Minimally displaced UCL avulsion fractures frequently have significant rotation that prevents successful fracture healing even with prompt cast immobilization.

  4. Science from Kepler Collateral Data: 50 Kilosecond per Year from 13 Million Stars

    NASA Technical Reports Server (NTRS)

    Kolodziejczak, J. J.; Caldwell, D. A.

    2012-01-01

    As each Kepler frame is read out, light from each star in a CCD column accumulates in successive pixels as they wait for the next row to be read out. This accumulation is the same in the masked rows at the start of the readout and virtual rows at the end of the readout as it is in the science data. A range of these "smear" rows are added together for each long cadence and sent to the ground for calibration purposes. We will introduce and describe this smear collateral data, discuss and demonstrate its potential use for scientific studies exclusive of Kepler calibration,[1,2] including global characteristics of stellar variability, which are influenced by parameters of galactic evolution.

  5. A new surgical technique for medial collateral ligament balancing: multiple needle puncturing.

    PubMed

    Bellemans, Johan; Vandenneucker, Hilde; Van Lauwe, Johan; Victor, Jan

    2010-10-01

    In this article, we present our experience with a new technique for medial soft tissue balancing, where we make multiple punctures in the medial collateral ligament (MCL) using a 19-gauge needle, to progressively stretch the MCL until a correct ligament balance is achieved. Ligament status was evaluated both before and after the procedure using computer navigation and mediolateral stress testing. The procedure was considered successful when 2 to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 34 of 35 cases, a progressive correction of medial tightness was achieved according to the above described criteria. One case was considered overreleased in extension. Needle puncturing is a new, effective, and safe technique for progressive correction of MCL tightness in the varus knee.

  6. On the collateral sesamoidean (suspensory navicular) ligament of equines: topographic relations and sensitive innervation.

    PubMed

    Palmieri, G; Sanna, L; Asole, A; Farina, V; Bo Minelli, L

    1990-01-01

    The origin and course of the collateral sesamoidean (suspensory navicular) ligament of the horse and ass and its attachment to the distal sesamoid bone were studied by means of dissection. Particular attention was given to the topographic relations between this ligament and the deep digital flexor tendon. Numerous sensitive nerve endings are present in this anatomical district. The free and encapsulated nerve endings, displayed by impregnating techniques, are mostly concentrated in the ligament tract connected to the above-named tendon and close to its attachment to the distal sesamoid angle. The nerve endings are identified as typical Pacini, Pacini-like and Golgi-Mazzoni corpuscles on account of their morphological features and are found isolated, grouped to form flower-sprays, lined up along the course of a single nerve fibre or grouped to originate poikilomorphous fibres.

  7. Ovarian Artery Embolization in Patients With Collateral Supply to Symptomatic Uterine Leiomyomata

    SciTech Connect

    Scheurig-Muenkler, C. Poellinger, A. Wagner, M. Hamm, B. Kroencke, T. J.

    2011-12-15

    Purpose: To evaluate the safety and outcome of ovarian artery embolization (OAE) in patients with collateral supply to symptomatic uterine leiomyomata. Materials and Methods: Thirteen patients with relevant leiomyoma perfusion by way of enlarged ovarian arteries underwent additional OAE during the same (N = 10) or a second procedure (N = 3). Uterine artery embolization (UAE) was performed bilaterally in 10 and unilaterally in 2 patients with a single artery. One patient had no typical uterine arteries but bilaterally enlarged ovarian arteries, prompting bilateral OAE. OAE was accomplished with coil embolization in one and particle embolization in 12 patients. Symptoms before therapy and clinical outcome were assessed using a standardized questionnaire. Contrast-enhanced magnetic resonance (MR) imaging after embolization was available in 11 of 13 patients and was used to determine the percentage of fibroid infarction. Results: UAE and OAE were technically successful in all patients. One patient experienced prolonged irritation at the puncture site. Median clinical follow-up time was 16 months (range 4-37). Ten of 13 patients showed improvement or complete resolution of clinical symptoms. One patient reported only slight improvement of her symptoms. These women presented with regular menses. Two patients (15%), 47 and 48 years, both with unilateral OAE, reported permanent amenorrhea directly after embolization. Their symptoms completely resolved. Seven patients showed complete and 4 showed >90% fibroid infarction after embolization therapy. Conclusions: OAE is technically safe and effective in patients with ovarian artery collateral supply to symptomatic uterine leiomyomata. The risk of permanent amenorrhea observed in this study is similar to the reported incidence after UAE.

  8. Redox-sensitive Akt and Src regulate coronary collateral growth in metabolic syndrome.

    PubMed

    Reed, Ryan; Potter, Barry; Smith, Erika; Jadhav, Rashmi; Villalta, Patricia; Jo, Hanjoong; Rocic, Petra

    2009-06-01

    We have recently shown that the inability of repetitive ischemia (RI) to activate p38 MAPK (p38) and Akt in metabolic syndrome [JCR:LA-cp (JCR)] rats was associated with impaired coronary collateral growth (CCG). Furthermore, Akt and p38 activation correlated with optimal O(2)(-). levels and were altered in JCR rats, and redox-sensitive p38 activation was required for CCG. Here, we determined whether the activation of Src, a possible upstream regulator, was altered in JCR rats and whether redox-dependent Src and Akt activation were required for CCG. CCG was assessed by myocardial blood flow (microspheres) and kinase activation was assessed by Western blot analysis in the normal zone and collateral-dependent zone (CZ). RI induced Src activation (approximately 3-fold) in healthy [Wistar-Kyoto (WKY)] animals but not in JCR animals. Akt inhibition decreased (approximately 50%), and Src inhibition blocked RI-induced CCG in WKY rats. Src inhibition decreased p38 and Akt activation. Myocardial oxidative stress (O(2)(-). and oxidized/reduced thiols) was measured quantitatively (X-band electron paramagnetic resonance). An antioxidant, apocynin, reduced RI-induced oxidative stress in JCR rats to levels induced by RI in WKY rats versus the reduction in WKY rats to very low levels. This resulted in a significant restoration of p38 (approximately 80%), Akt (approximately 65%), and Src (approximately 90%) activation in JCR rats but decreased the activation in WKY rats (p38: approximately 45%, Akt: approximately 65%, and Src: approximately 100%), correlating with reduced CZ flow in WKY rats (approximately 70%), but significantly restored CZ flow in JCR rats (approximately 75%). We conclude that 1) Akt and Src are required for CCG, 2) Src is a redox-sensitive upstream regulator of RI-induced p38 and Akt activation, and 3) optimal oxidative stress levels are required for RI-induced p38, Akt, and Src activation and CCG.

  9. Ethical responsibilities toward indirect and collateral participants in pragmatic clinical trials.

    PubMed

    Smalley, Jaye Bea; Merritt, Maria W; Al-Khatib, Sana M; McCall, Debbe; Staman, Karen L; Stepnowsky, Carl

    2015-10-01

    Pragmatic clinical trials are designed to inform decision makers about the benefits, burdens, and risks of health interventions in real-world settings. Pragmatic clinical trials often use for research purposes data collected in the course of clinical practice. The distinctive features of pragmatic clinical trials demand fresh thinking about what is required to act properly toward people affected by their conduct, in ways that go beyond ensuring the protection of rights and welfare for "human research subjects" under conventional research ethics regulations. To stimulate such work, we propose to distinguish among categories of research participants in pragmatic clinical trials as follows: Direct participants: (1) individuals being directly intervened upon and/or (2) individuals from whom personal identifiable data are being collected for the purposes of the pragmatic clinical trial. Indirect participants: individuals who are (1) not identified as direct participants and (2) whose rights and welfare may be affected by the intervention through their routine exposure to the environment in which the intervention is being deployed. Collateral participants: patient groups and other stakeholder communities who may be otherwise affected by the occurrence and findings of the pragmatic clinical trial. We illustrate these distinctions with case examples and discuss the distinctive responsibilities of researchers and pragmatic clinical trial leadership toward each type of participant. We suggest that pragmatic clinical trial investigators, institutional review boards, health systems leaders, and others engaged in the research enterprise work together to identify these participants. For indirect participants, risks and benefits to which they are exposed should be weighed to ensure that their rights and welfare are protected accordingly, and communication strategies should be considered to help them make well-informed decisions. Collateral participants could provide input on the

  10. Collateral circulation in ferrets (Mustela putorius) during temporary occlusion of the caudal vena cava.

    PubMed

    Calicchio, Kristina W; Bennett, R Avery; Laraio, Leonard C; Weisse, Chick; Zwingenberger, Allison L; Rosenthal, Karen L; Johnston, Matthew S; Campbell, Vicki L; Solomon, Jeffrey A

    2016-05-01

    OBJECTIVE To determine whether extent of collateral circulation would change during temporary occlusion of the caudal vena cava (CVC) in ferrets (Mustela putorius), a pressure change would occur caudal to the occlusion, and differences would exist between the sexes with respect to those changes. ANIMALS 8 adult ferrets (4 castrated males and 4 spayed females). PROCEDURES Ferrets were anesthetized. A balloon occlusion catheter was introduced through a jugular vein, passed into the CVC by use of fluoroscopy, positioned cranial to the right renal vein, and inflated for 20 minutes. Venography was performed 5 and 15 minutes after occlusion. Pressure in the CVC caudal to the occlusion was measured continuously. A CBC, plasma biochemical analysis, and urinalysis were performed immediately after the procedure and 2 or 3 days later. RESULTS All 8 ferrets survived the procedure; no differences were apparent between the sexes. Vessels providing collateral circulation were identified in all ferrets, indicating blood flow to the paravertebral venous plexus. Complications observed prior to occlusion included atrial and ventricular premature contractions. Complications after occlusion included bradycardia, seizures, and extravasation of contrast medium. Mean baseline CVC pressure was 5.4 cm H2O. During occlusion, 6 ferrets had a moderate increase in CVC pressure (mean, 24.3 cm H2O) and 2 ferrets had a marked increase in CVC pressure to > 55.0 cm H2O. CONCLUSIONS AND CLINICAL RELEVANCE Caval occlusion for 20 minutes was performed in healthy ferrets with minimal adverse effects noted within the follow-up period and no apparent differences between sexes. The CVC pressure during occlusion may be prognostic in ferrets undergoing surgical ligation of the CVC, which commonly occurs during adrenal tumor resection.

  11. Excimer laser debridement of necrotic erosions of skin without collateral damage

    NASA Astrophysics Data System (ADS)

    Wynne, James J.; Felsenstein, Jerome M.; Trzcinski, Robert; Zupanski-Nielsen, Donna; Connors, Daniel P.

    2011-07-01

    Pulsed ArF excimer laser radiation at 6.4 eV, at fluence exceeding the ablation threshold, will debride burn eschar and other dry necrotic erosions of the skin. Debridement will cease when sufficiently moist viable tissue is exposed, due to absorption by aqueous chloride ions (Cl-) through the non-thermal process of electron photodetachment, thereby inhibiting collateral damage to the viable tissue. ArF excimer laser radiation debrides/ablates ~1 micron of tissue with each pulse. While this provides great precision in controlling the depth of debridement, the process is relatively time-consuming. In contrast, XeCl excimer laser radiation debrides ~8 microns of tissue with each pulse. However the 4.0 eV photon energy of the XeCl excimer laser is insufficient to photodetach an electron from a Cl- ion, so blood or saline will not inhibit debridement. Consequently, a practical laser debridement system should incorporate both lasers, used in sequence. First, the XeCl excimer laser would be used for accelerated debridement. When the necrotic tissue is thinned to a predetermined thickness, the ArF excimer laser would be used for very precise and well-controlled debridement, removing ultra-thin layers of material with each pulse. Clearly, the use of the ArF laser is very desirable when debriding very close to the interface between necrotic tissue and viable tissue, where the overall speed of debridement need not be so rapid and collateral damage to viable tissue is undesirable. Such tissue will be sterile and ready for further treatment, such as a wound dressing and/or a skin graft.

  12. Unstable Simple Elbow Dislocation Treated with the Repair of Lateral Collateral Ligament Complex

    PubMed Central

    Yi, Jin Woong; Lee, Jung Bum; Lee, Dae Hee; Park, Won Keun; Kim, Sun Joong

    2015-01-01

    Background Unstable simple elbow dislocation (USED) repair is challenged by the maintenance of joint reduction; hence, primary repair or reconstruction of disrupted ligaments is required to maintain the congruency and allow early motion of the elbow. We evaluated the effectiveness and the outcome of lateral collateral ligament (LCL) complex repair with additional medial collateral ligament (MCL) repair in cases of USED. Methods We retrospectively reviewed 21 cases of diagnosed USED without fractures around the elbow that were treated with primary ligament repair. In all cases, anatomical repair of LCL complex with or without common extensor origin was performed using suture anchor and the bone tunnel method. Next, the instability and congruency of elbow for a full range of motion were evaluated under the image intensifier. MCL was repaired only if unstable or incongruent elbow was observed. Clinical outcomes were evaluated using the Mayo elbow performance score (MEPS) and radiographic outcomes on last follow-up images. Results All cases achieved a stable elbow on radiographic and clinical results. LCL complex repair alone was sufficient to obtain the stable elbow in 17 of 21 cases. Four cases required additional MCL repair after restoration of the LCL complex. The overall mean MEPS was 91 (range, 70 to 100): excellent in 12 cases, good in 7 cases, and fair in 2 cases. All 17 cases with LCL complex repair only and 2 of 4 cases with additional MCL repair had excellent or good results by MEPS. Conclusions USED requires surgical treatment to achieve a congruent and stable joint. If the repair of lateral stabilizer such as LCL complex acquires enough joint stability to maintain a full range of motion, it may not be necessary to repair the medial stabilizer in all cases of USED. PMID:26217472

  13. Contralateral needling at unblocked collaterals for hemiplegia following acute ischemic stroke

    PubMed Central

    Gao, Huanmin; Li, Xugang; Gao, Xia; Ma, Benxu

    2013-01-01

    Hemiplegia caused by stroke indicates dysfunction of the network between the brain and limbs, namely collateral shock in the brain. Contralateral needling is the insertion of needles into acupoints on the relative healthy side of the body to treat diseases such as apoplexy. However, there is little well-designed and controlled clinical evidence for this practice. This study investigated whether contralateral needling could treat hemiplegia after acute ischemic stroke in 106 randomly selected patients with acute ischemic stroke. These patients were randomly assigned to three groups: 45 in the contralateral needling group, receiving acupuncture on the unaffected limbs; 45 in the tional acupuncture group, receiving acupuncture on the hemiplegic limbs; and 16 in the control group, receiving routine treatments without acupuncture. Acupuncture at acupoints Chize (LU5) in the upper limb and Jianliao (TE14) in the lower limb was performed for 45 minutes daily for 30 consecutive days. The therapeutic effective rate, Neurological Deficit Score, Modified Barthel Index and Fugl-Meyer Assessment were evaluated. The therapeutic effective rate of contralateral needling was higher than that of conventional acupuncture (46.67% vs. 31.11%, P < 0.05). The neurological deficit score of contralateral needling was significantly decreased compared with conventional acupuncture (P < 0.01). The Modified Barthel Index and Fugl-Meyer Assessment score of contralateral needling increased more significantly than those of conventional acupuncture (both P < 0.01). The present findings suggest that contralateral needling unblocks collaterals and might be more effective than conventional acupuncture in the treatment of hemiplegia following acute ischemic stroke. PMID:25206612

  14. Recursive Branching Simulated Annealing Algorithm

    NASA Technical Reports Server (NTRS)

    Bolcar, Matthew; Smith, J. Scott; Aronstein, David

    2012-01-01

    This innovation is a variation of a simulated-annealing optimization algorithm that uses a recursive-branching structure to parallelize the search of a parameter space for the globally optimal solution to an objective. The algorithm has been demonstrated to be more effective at searching a parameter space than traditional simulated-annealing methods for a particular problem of interest, and it can readily be applied to a wide variety of optimization problems, including those with a parameter space having both discrete-value parameters (combinatorial) and continuous-variable parameters. It can take the place of a conventional simulated- annealing, Monte-Carlo, or random- walk algorithm. In a conventional simulated-annealing (SA) algorithm, a starting configuration is randomly selected within the parameter space. The algorithm randomly selects another configuration from the parameter space and evaluates the objective function for that configuration. If the objective function value is better than the previous value, the new configuration is adopted as the new point of interest in the parameter space. If the objective function value is worse than the previous value, the new configuration may be adopted, with a probability determined by a temperature parameter, used in analogy to annealing in metals. As the optimization continues, the region of the parameter space from which new configurations can be selected shrinks, and in conjunction with lowering the annealing temperature (and thus lowering the probability for adopting configurations in parameter space with worse objective functions), the algorithm can converge on the globally optimal configuration. The Recursive Branching Simulated Annealing (RBSA) algorithm shares some features with the SA algorithm, notably including the basic principles that a starting configuration is randomly selected from within the parameter space, the algorithm tests other configurations with the goal of finding the globally optimal

  15. Calcium-dependent signalling is essential during collateral growth in the pig hind limb-ischemia model.

    PubMed

    Troidl, C; Nef, H; Voss, S; Schilp, A; Kostin, S; Troidl, K; Szardien, S; Rolf, A; Schmitz-Rixen, T; Schaper, W; Hamm, C W; Elsässer, A; Möllmann, H

    2010-07-01

    We investigated the effect of pharmacological activation of the Ca(2+)-channel transient receptor potential cation channel, subfamily V, member 4 (TRPV4) on collateral growth in a pig hind limb-ischemia model thereby identifying subcellular mechanisms. Domestic pigs received femoral artery ligature and were randomly assigned to one of the following groups (each n=6): (1) 4alpha-phorbol 12,13-didecanoate (4alphaPDD) treatment; (2) treatment with an arterio-venous shunt (AV-shunt) distal to the occlusion; or (3) implantation of NaCl-filled minipump. Six sham-operated pigs acted as controls. Aortic and peripheral mean arterial pressure (MAP) measurements were performed to assess the collateral flow index (CFI). Tissue was isolated from M. quadriceps for immunohistochemistry and from isolated collateral arteries for quantitative real time PCR (qRT-PCR). Shortly after ligature the CFI dropped from 0.96+/-0.02 to 0.21+/-0.02 in all ligature-treated groups. In ligature-only-treated pigs CFI increased to 0.56+/-0.03 after 7days. Treatment with 4alphaPDD led to an enhancement of CFI compared with ligature alone (0.73+/-0.03). CD31-staining showed improved arteriolar density. Increased Ki67 staining in collaterals indicated proliferation. qRT-PCR and Western blot analysis showed upregulation or modulation of Ca(2+)-dependent transcription factors nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1), Kv channel interacting protein 3, calsenilin (KCNIP3/CSEN/DREAM), and myocyte enhancer factor 2C (MEF2C) in 4alphaPDD- and AV-shunt-treated pigs compared with controls. Improved CFI after 4alphaPDD treatment identifies TRPV4 as an initial fluid shear-stress sensor and collateral remodelling and growth trigger. Subcellularly, modulation of Ca(2+)-dependent transcription factors indicates a pivotal role for Ca(2+)-signalling during arteriogenesis.

  16. Vegetation survey of PEN Branch wetlands

    SciTech Connect

    Not Available

    1991-01-01

    A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

  17. Research program of the Geodynamics Branch

    NASA Technical Reports Server (NTRS)

    Kahn, W. D. (Editor); Cohen, S. C. (Editor); Boccucci, B. S. (Editor)

    1986-01-01

    This report is the Fourth Annual Summary of the Research Program of the Geodynamics Branch. The branch is located within the Laboratory for Terrestrial Physics of the Space and Earth Sciences Directorate of the Goddard Space Flight Center. The research activities of the branch staff cover a broad spectrum of geoscience disciplines including: tectonophysics, space geodesy, geopotential field modeling, and dynamic oceanography. The NASA programs which are supported by the work described in this document include the Geodynamics and Ocean Programs, the Crustal Dynamics Project and the proposed Ocean Topography Experiment (TOPEX). The reports highlight the investigations conducted by the Geodynamics Branch staff during calendar year 1985. The individual papers are grouped into chapters on Crustal Movements and Solid Earth Dynamics, Gravity Field Modeling and Sensing Techniques, and Sea Surface Topography. Further information on the activities of the branch or the particular research efforts described herein can be obtained through the branch office or from individual staff members.

  18. Combining living anionic polymerization with branching reactions in an iterative fashion to design branched polymers.

    PubMed

    Higashihara, Tomoya; Sugiyama, Kenji; Yoo, Hee-Soo; Hayashi, Mayumi; Hirao, Akira

    2010-06-16

    This paper reviews the precise synthesis of many-armed and multi-compositional star-branched polymers, exact graft (co)polymers, and structurally well-defined dendrimer-like star-branched polymers, which are synthetically difficult, by a commonly-featured iterative methodology combining living anionic polymerization with branched reactions to design branched polymers. The methodology basically involves only two synthetic steps; (a) preparation of a polymeric building block corresponding to each branched polymer and (b) connection of the resulting building unit to another unit. The synthetic steps were repeated in a stepwise fashion several times to successively synthesize a series of well-defined target branched polymers.

  19. Mechanical Components Branch Test Facilities and Capabilities

    NASA Technical Reports Server (NTRS)

    Oswald, Fred B.

    2004-01-01

    The Mechanical Components Branch at NASA Glenn Research Center formulates, conducts, and manages research focused on propulsion systems for both present and advanced aeronautical and space vehicles. The branch is comprised of research teams that perform basic research in three areas: mechanical drives, aerospace seals, and space mechanisms. Each team has unique facilities for testing aerospace hardware and concepts. This report presents an overview of the Mechanical Components Branch test facilities.

  20. Toward improved branch prediction through data mining.

    SciTech Connect

    Hemmert, K. Scott; Johnson, D. Eric

    2009-09-01

    Data mining and machine learning techniques can be applied to computer system design to aid in optimizing design decisions, improving system runtime performance. Data mining techniques have been investigated in the context of branch prediction. Specifically, a comparison of traditional branch predictor performance has been made to data mining algorithms. Additionally, the possiblity of whether additional features available within the architectural state might serve to further improve branch prediction has been evaluated. Results show that data mining techniques indicate potential for improved branch prediction, especially when register file contents are included as a feature set.

  1. Branched silver nanowires as controllable plasmon routers.

    PubMed

    Fang, Yurui; Li, Zhipeng; Huang, Yingzhou; Zhang, Shunping; Nordlander, Peter; Halas, Naomi J; Xu, Hongxing

    2010-05-12

    Using polarization dependent scattering spectroscopy, we investigate plasmon propagation on branched silver nanowires. By controlling the polarization of the incident laser light, the wire plasmons can be routed into different wire branches and result in light emission from the corresponding wire ends. This routing behavior is found to be strongly dependent on the wavelength of light. Thus for certain incident polarizations, light of different wavelength will be routed into different branches. The branched nanowire can thus serve as a controllable router and multiplexer in integrated plasmonic circuits.

  2. Clinical and Translational Epidemiology Branch (CTEB)

    Cancer.gov

    The Clinical and Translational Epidemiology Branch focuses on factors that influence cancer progression, recurrence, survival, and other treatment outcomes, and factors associated with cancer development.

  3. Stochastic model for supersymmetric particle branching process

    NASA Astrophysics Data System (ADS)

    Zhang, Yuanyuan; Chan, Aik Hui; Oh, Choo Hiap

    2017-01-01

    We develop a stochastic branching model to describe the jet evolution of supersymmetric (SUSY) particles. This model is a modified two-phase branching process, or more precisely, a two-phase simple birth process plus Poisson process. Both pure SUSY partons initiated jets and SUSY plus ordinary partons initiated jets scenarios are considered. The stochastic branching equations are established and the Multiplicity Distributions (MDs) are derived for these two scenarios. We also fit the distribution of the general case (SUSY plus ordinary partons initiated jets) with experimental data. The fitting shows the SUSY particles have not participated in branching at current collision energy yet.

  4. Alcohol septal ablation for hypertrophic obstructive cardiomyopathy in a patient with a chronic total occlusion of the right coronary artery: “beware of collateral damage”

    PubMed Central

    de Hemptinne, Quentin; Picard, Fabien

    2017-01-01

    Alcohol septal ablation (ASA) is an effective semi-invasive alternative to surgical myectomy in selected patients for the management of severely symptomatic and drug-refractory hypertrophic obstructive cardiomyopathy (HOCM). One contraindication of this procedure is the presence of collateral flow originating from the target septal perforator to a remote myocardial territory. In such circumstances, ethanol injection could cause remote non-target myocardial necrosis in the collateralized territory. Percutaneous revascularization of the collateralized vessel prior to ASA might cope with this contraindication by restoring normal antegrade flow in the occluded artery. We report a case that illustrates the feasibility and efficacy of such strategy. PMID:28164017

  5. Antidromic propagation of action potentials in branched axons: implications for the mechanisms of action of deep brain stimulation.

    PubMed

    Grill, Warren M; Cantrell, Meredith B; Robertson, Matthew S

    2008-02-01

    Electrical stimulation of the central nervous system creates both orthodromically propagating action potentials, by stimulation of local cells and passing axons, and antidromically propagating action potentials, by stimulation of presynaptic axons and terminals. Our aim was to understand how antidromic action potentials navigate through complex arborizations, such as those of thalamic and basal ganglia afferents-sites of electrical activation during deep brain stimulation. We developed computational models to study the propagation of antidromic action potentials past the bifurcation in branched axons. In both unmyelinated and myelinated branched axons, when the diameters of each axon branch remained under a specific threshold (set by the antidromic geometric ratio), antidromic propagation occurred robustly; action potentials traveled both antidromically into the primary segment as well as "re-orthodromically" into the terminal secondary segment. Propagation occurred across a broad range of stimulation frequencies, axon segment geometries, and concentrations of extracellular potassium, but was strongly dependent on the geometry of the node of Ranvier at the axonal bifurcation. Thus, antidromic activation of axon terminals can, through axon collaterals, lead to widespread activation or inhibition of targets remote from the site of stimulation. These effects should be included when interpreting the results of functional imaging or evoked potential studies on the mechanisms of action of DBS.

  6. Asymptotics of Simple Branching Populations

    NASA Astrophysics Data System (ADS)

    Huillet, Thierry; Kłopotowski, Andrzej; Porzio, Anna

    1995-09-01

    In this paper we study a simple deterministic tree structure: an initial individual generates a finite number of offspring, each of which has given integer valued lifetime, iterating the same procedure when dying. Three asymptotic distributions of this asynchronous deterministic branching procedure are considered: the generation distribution, the ability of individuals to generate offspring and the age distribution. Thermodynamic formalism is then developped to reveal the multifractal nature of the mass splitting associated to our process. On considère l'itération d'une structure déterministe arborescente selon laquelle un ancêtre engendre un nombre fini de descendants dont la durée de vie (à valeurs entières) est donnée. Dans un premier temps on s'intéresse aux trois distributions asymptotiques suivantes : répartition des générations, aptitude à engendrer des descendants et répartition selon l'âge. Ensuite nous développons le formalisme thermodynamique pour mettre en évidence le caractère multifractal de la scission d'une masse unitaire associée à cette arborescence.

  7. Pacific Coastal Ecology Branch: Research Overview

    EPA Science Inventory

    The Pacific Coastal Ecology Branch, Newport, Oregon is part of the Western Ecology Division of the National Health and Environmental Effects Research Laboratory of the U.S. EPA. The Branch conducts research and provides scientific technical support to Headquarters and Regional O...

  8. An archetypal mechanism for branching organogenesis.

    PubMed

    Clément, Raphaël; Mauroy, Benjamin

    2014-02-01

    Branched structures are ubiquitous in nature, both in living and non-living systems. While the functional benefits of branching organogenesis are straightforward, the developmental mechanisms leading to the repeated branching of epithelia in surrounding mesoderm remain unclear. Both molecular and physical aspects of growth control seem to play a critical role in shape emergence and maintenance. On the molecular side, the existence of a gradient of growth-promoting ligand between epithelial tips and distal mesenchyme seems to be common to branched organs. On the physical side, the branching process seems to require a mechanism of real-time adaptation to local geometry, as suggested by the self-avoiding nature of branching events. In this paper, we investigate the outcomes of a general three-dimensional growth model, in which epithelial growth is implemented as a function of ligand income, while the mesenchyme is considered as a proliferating viscous medium. Our results suggest that the existence of a gradient of growth-promoting ligand between distal and proximal mesenchyme implies a growth instability of the epithelial sheet, resulting in spontaneous self-avoiding branching morphogenesis. While the general nature of the model prevents one from fitting the development of specific organs, it suggests that few ingredients are actually required to achieve branching organogenesis.

  9. On an Integral with Two Branch Points

    ERIC Educational Resources Information Center

    de Oliveira, E. Capelas; Chiacchio, Ary O.

    2006-01-01

    The paper considers a class of real integrals performed by using a convenient integral in the complex plane. A complex integral containing a multi-valued function with two branch points is transformed into another integral containing a pole and a unique branch point. As a by-product we obtain a new class of integrals which can be calculated in a…

  10. Anaphora and Branching Direction in Japanese.

    ERIC Educational Resources Information Center

    O'Grady, William; And Others

    1994-01-01

    This paper constitutes a response to Lust and Mazuka's (1989) defense of the Principal Branching parameter and their critique of O'Grady, Suzuki-Wei, and Cho's (1986) experiment, which purported to show that even children learning left-branching languages exhibit a preference for forward patterns of anaphora. (Contains 16 references.) (JL)

  11. Suppression of branches in Eucalyptus trees.

    PubMed

    Senthalir, P; Sharanya, S; Paramathma, M

    2004-06-01

    The effect of neem oil, which acts as a suckericide in tobacco, on branch suppression in Eucalyptus tereticornis was assessed to help maximize stem biomass. Lateral branches of selected trees were pruned, and neem oil solutions at concentrations of either 80%, 40%, 20%, 10%, or 0% (untreated control) were applied to leaf axils of the pruned branches. Regeneration of branches was suppressed, and the magnitude of suppression was proportional to the concentration of neem oil. Compared to the control, the percentage reduction in branching at 80% neem oil was 41.6%. When regenerated branches were repruned and neem oil applied at either 100%, 80%, or 0% (control), the regenerating ability of these branches was severely repressed by 78% at 100% neem oil relative to the control. Apical shoots were also topped and treated at either 100% or 0% (control) neem oil to identify the principal suppressive component in neem oil. The principal component azadirachtin was tested at 375, 750, 1500, 3125, 6250, 12 500, 25 000, 50 000, and 100 000 ppm and 0 ppm as the control. Reduction in the coppicing shoot was as high as 85%. Azadirachtin was responsible for the suppression. By pruning the lateral branches with neem oil, wasteful consumption of photosynthates can be precluded and the stem biomass maximized.

  12. Branching out Has So Much to Offer

    ERIC Educational Resources Information Center

    Murray, Joe

    2012-01-01

    In 1989 there were thirty ATM branches nationally. In January 2012 there were just twelve ATM branches with another three "proposed". How can that happen? How did it happen? Maybe the most pertinent question is: Why did it happen? There is no single answer to the last question, but perhaps it was something to do with the changes that…

  13. Lung epithelial branching program antagonizes alveolar differentiation.

    PubMed

    Chang, Daniel R; Martinez Alanis, Denise; Miller, Rachel K; Ji, Hong; Akiyama, Haruhiko; McCrea, Pierre D; Chen, Jichao

    2013-11-05

    Mammalian organs, including the lung and kidney, often adopt a branched structure to achieve high efficiency and capacity of their physiological functions. Formation of a functional lung requires two developmental processes: branching morphogenesis, which builds a tree-like tubular network, and alveolar differentiation, which generates specialized epithelial cells for gas exchange. Much progress has been made to understand each of the two processes individually; however, it is not clear whether the two processes are coordinated and how they are deployed at the correct time and location. Here we show that an epithelial branching morphogenesis program antagonizes alveolar differentiation in the mouse lung. We find a negative correlation between branching morphogenesis and alveolar differentiation temporally, spatially, and evolutionarily. Gain-of-function experiments show that hyperactive small GTPase Kras expands the branching program and also suppresses molecular and cellular differentiation of alveolar cells. Loss-of-function experiments show that SRY-box containing gene 9 (Sox9) functions downstream of Fibroblast growth factor (Fgf)/Kras to promote branching and also suppresses premature initiation of alveolar differentiation. We thus propose that lung epithelial progenitors continuously balance between branching morphogenesis and alveolar differentiation, and such a balance is mediated by dual-function regulators, including Kras and Sox9. The resulting temporal delay of differentiation by the branching program may provide new insights to lung immaturity in preterm neonates and the increase in organ complexity during evolution.

  14. Polyphyly of true branching cyanobacteria (Stigonematales).

    PubMed

    Gugger, Muriel F; Hoffmann, Lucien

    2004-03-01

    Cyanobacteria with true branching are classified in Subsection V (formerly order Stigonematales) in the phylum CYANOBACTERIA: They exhibit a high degree of morphological complexity and are known from particular biotopes. Only a few stigonematalean morphotypes have been cultured, and therefore the high variability of morphotypes found in nature is under-represented in culture. Axenic cultures of Chlorogloeopsis and Fischerella sensu Rippka et al. were, to date, the only representatives of this Subsection in phylogenetic studies. The 16S rDNA sequence analysis data in this report confirm that heterocyst-forming cyanobacteria are a monophyletic group. However, unlike previous studies have suggested, these 16S rDNA data on new Stigonematales strains show that the true branching cyanobacteria are polyphyletic and can be separated into at least two major groups defined by their branching type, the first group being characterized by T-branching and the second group by Y-branching. Cyanobacteria with intercalary heterocysts and either no branching or false-branching also formed separate clusters. In consequence, our phylogenetic data do not correlate with the bacteriological and traditional classifications, which distinguish filamentous heterocystous cyanobacteria with or without true branching (Nostocales/Stigonematales).

  15. Phytochrome regulation of branching in Arabidopsis.

    PubMed

    Finlayson, Scott A; Krishnareddy, Srirama R; Kebrom, Tesfamichael H; Casal, Jorge J

    2010-04-01

    The red light:far-red light ratio perceived by phytochromes controls plastic traits of plant architecture, including branching. Despite the significance of branching for plant fitness and productivity, there is little quantitative and mechanistic information concerning phytochrome control of branching responses in Arabidopsis (Arabidopsis thaliana). Here, we show that in Arabidopsis, the negative effects of the phytochrome B mutation and of low red light:far-red light ratio on branching were largely due to reduced bud outgrowth capacity and an increased degree of correlative inhibition acting on the buds rather than due to a reduced number of leaves and buds available for branching. Phytochrome effects on the degree of correlative inhibition required functional BRANCHED1 (BRC1), BRC2, AXR1, MORE AXILLARY GROWTH2 (MAX2), and MAX4. The analysis of gene expression in selected buds indicated that BRC1 and BRC2 are part of different gene networks. The BRC1 network is linked to the growth capacity of specific buds, while the BRC2 network is associated with coordination of growth among branches. We conclude that the branching integrators BRC1 and BRC2 are necessary for responses to phytochrome, but they contribute differentially to these responses, likely acting through divergent pathways.

  16. Toward an understanding of fibrin branching structure

    NASA Astrophysics Data System (ADS)

    Fogelson, Aaron L.; Keener, James P.

    2010-05-01

    The blood clotting enzyme thrombin converts fibrinogen molecules into fibrin monomers which polymerize to form a fibrous three-dimensional gel. The concentration of thrombin affects the architecture of the resulting gel, in particular, a higher concentration of thrombin produces a gel with more branch points per unit volume and with shorter fiber segments between branch points. We propose a mechanism by which fibrin branching can occur and show that this mechanism can lead to dependence of the gel’s structure (at the time of gelation) on the rate at which monomer is supplied. A higher rate of monomer supply leads to a gel with a higher branch concentration and with shorter fiber segments between branch points. The origin of this dependence is explained.

  17. Using branching simulations in treatment fidelity plans.

    PubMed

    Kovach, Christine R; Rababa, Mohammad

    2014-01-01

    The purpose of this article is to present a new approach to treatment fidelity using branching simulations. Branching simulations are case scenarios that require the user to generate a series of step-by-step decisions and actions. The user is given immediate feedback on the consequences of his or her decisions and actions. Branching simulations may be a particularly useful fidelity strategy for interventions that require clinical decision making represented in terms of a flow of critical thinking and action steps. Results of fidelity testing in the current study using branching simulations revealed that 15 (22%) of 67 interventionists scored below the study's a priori 80% criterion for full retraining and retesting. Thirty (45%) interventionists needed partial retraining in using specific components of the intervention. Potential threats to internal validity posed by inadequate or erroneous adherence to multicomponent intervention protocols can be decreased through treatment fidelity using branching simulations.

  18. Root branching: mechanisms, robustness, and plasticity.

    PubMed

    Dastidar, Mouli Ghosh; Jouannet, Virginie; Maizel, Alexis

    2012-01-01

    Plants are sessile organisms that must efficiently exploit their habitat for water and nutrients. The degree of root branching impacts the efficiency of water uptake, acquisition of nutrients, and anchorage. The root system of plants is a dynamic structure whose architecture is determined by modulation of primary root growth and root branching. This plasticity relies on the continuous integration of environmental inputs and endogenous developmental programs controlling root branching. This review focuses on the cellular and molecular mechanisms involved in the regulation of lateral root distribution, initiation, and organogenesis with the main focus on the root system of Arabidopsis thaliana. We also examine the mechanisms linking environmental changes to the developmental pathways controlling root branching. Recent progress that emphasizes the parallels to the formation of root branches in other species is discussed.

  19. Collateral development and spinal motor reorganization after nerve injury and repair

    PubMed Central

    Yu, Youlai; Zhang, Peixun; Han, Na; Kou, Yuhui; Yin, Xiaofeng; Jiang, Baoguo

    2016-01-01

    Functional recovery is often unsatisfactory after severe extended nerve defects or proximal nerve trunks injuries repaired by traditional repair methods, as the long regeneration distance for the regenerated axons to reinnervate their original target end-organs. The proximal nerve stump can regenerate with many collaterals that reinnervate the distal stump after peripheral nerve injury, it may be possible to use nearby fewer nerve fibers to repair more nerve fibers at the distal end to shorten the regenerating distance. In this study, the proximal peroneal nerve was used to repair both the distal peroneal and tibial nerve. The number and location of motor neurons in spinal cord as well as functional and morphological recovery were assessed at 2 months, 4 months and 8 months after nerve repair, respectively. Projections from the intact peroneal and tibial nerves were also studied in normal animals. The changes of motor neurons were assessed using the retrograde neurotracers FG and DiI to backlabel motor neurons that regenerate axons into two different pathways. To evaluate the functional recovery, the muscle forces and sciatic function index were examined. The muscles and myelinated axons were assessed using electrophysiology and histology. The results showed that all labeled motor neurons after nerve repair were always confined within the normal peroneal nerve pool and nearly all the distribution of motor neurons labeled via distal different nerves was disorganized as compared to normal group. However, there was a significant decline in the number of double labeled motor neurons and an obvious improvement with respect to the functional and morphological recovery between 2 and 8 months. In addition, the tibial/peroneal motor neuron number ratio at different times was 2.11±0.05, 2.13±0.08, 2.09±0.12, respectively, and was close to normal group (2.21±0.09). Quantitative analysis showed no significant morphological differences between myelinated nerve fibers

  20. Collateral development and spinal motor reorganization after nerve injury and repair.

    PubMed

    Yu, Youlai; Zhang, Peixun; Han, Na; Kou, Yuhui; Yin, Xiaofeng; Jiang, Baoguo

    2016-01-01

    Functional recovery is often unsatisfactory after severe extended nerve defects or proximal nerve trunks injuries repaired by traditional repair methods, as the long regeneration distance for the regenerated axons to reinnervate their original target end-organs. The proximal nerve stump can regenerate with many collaterals that reinnervate the distal stump after peripheral nerve injury, it may be possible to use nearby fewer nerve fibers to repair more nerve fibers at the distal end to shorten the regenerating distance. In this study, the proximal peroneal nerve was used to repair both the distal peroneal and tibial nerve. The number and location of motor neurons in spinal cord as well as functional and morphological recovery were assessed at 2 months, 4 months and 8 months after nerve repair, respectively. Projections from the intact peroneal and tibial nerves were also studied in normal animals. The changes of motor neurons were assessed using the retrograde neurotracers FG and DiI to backlabel motor neurons that regenerate axons into two different pathways. To evaluate the functional recovery, the muscle forces and sciatic function index were examined. The muscles and myelinated axons were assessed using electrophysiology and histology. The results showed that all labeled motor neurons after nerve repair were always confined within the normal peroneal nerve pool and nearly all the distribution of motor neurons labeled via distal different nerves was disorganized as compared to normal group. However, there was a significant decline in the number of double labeled motor neurons and an obvious improvement with respect to the functional and morphological recovery between 2 and 8 months. In addition, the tibial/peroneal motor neuron number ratio at different times was 2.11±0.05, 2.13±0.08, 2.09±0.12, respectively, and was close to normal group (2.21±0.09). Quantitative analysis showed no significant morphological differences between myelinated nerve fibers

  1. Intracranial collateral pathways assessed by contrast-enhanced three-dimensional transcranial color-coded sonography.

    PubMed

    Wessels, Tiemo; Bozzato, Alessandro; Mull, Michael; Klötzsch, Christof

    2004-11-01

    Individual parameter settings of the duplex machine and limited insonation angles may influence the visualization of small intracranial vessels in 2-D transcranial color-coded sonography. The aim of our study was the morphologic assessment of intracranial collateral pathways (first auditory area celiac artery, A(1)CA; anterior communicating artery, AComA; first parental generation celiac artery P(1)CA; posterior communicating artery, PComA) using 3-D transcranial color-coded duplex sonography (3-D TCCS) and digital subtraction angiography (DSA). A total of 41 patients with large vessel disease and 30 patients who had suffered subarachnoidal hemorrhage (mean age 52 +/- 15 years) were involved. In all patients, angiography was performed within 10 days following 3-D sonography. The patients were investigated with a color-coded duplex system using the power mode. Contrast enhancement was achieved by continuous infusion of a galactose-based echo-enhancer using a perfusor pump. The 3-D system consists of an electromagnet that induces a low-intensity magnetic field near the head of the patient. A magnetic position sensor is attached to the ultrasound (US) probe and transmits the spatial orientation to a personal computer, which also receives the corresponding 2-D images from the video port of the duplex machine. Angiography revealed a "complete" circle of Willis in one third of the patients and, in the remaining patients at least one vessel was hypoplastic or absent. Sufficient temporal bone windows allowed the sonographic investigation of 466 (94%) of 497 expected arterial segments. The comparison of both techniques resulted in a weighted kappa value of 0.56 for the A(1)CA and 0.63 for the AComA. In the posterior circulation kappa values of 0.56 for the P(1)CA and 0.43 for the PComA were calculated. In 50 vessels (10%), 3-D sonography misdiagnosed the diameter of a collateral vessel as normal and angiography revealed hypoplasia or aplasia of this vessel. The main

  2. POST OPERATIVE REHABILITATION OF GRADE III MEDIAL COLLATERAL LIGAMENT INJURIES: EVIDENCE BASED REHABILITATION AND RETURN TO PLAY.

    PubMed

    Logan, Catherine A; O'Brien, Luke T; LaPrade, Robert F

    2016-12-01

    The medial collateral ligament is the most commonly injured ligament of the knee, with injury generally sustained in the athletic population as a result of valgus contact with or without tibial external rotation. The capacity of the medial collateral ligament to heal has been demonstrated in both laboratory and clinical studies; however, complete ruptures heal less consistently and may result in persistent instability. When operative intervention is deemed necessary, anatomical medial knee reconstruction is recommended. Post-operative rehabilitation focuses on early motion and the return of normal neuromuscular firing patterns with progression based on attainment of specific phase criteria and goals. The purpose of this clinical commentary is to discuss the determinants of phase progression and the importance of objectively assessing readiness for advancement that is consistent with post-operative healing. Additional tests and validated measures to assess readiness for sport are also presented.

  3. POST OPERATIVE REHABILITATION OF GRADE III MEDIAL COLLATERAL LIGAMENT INJURIES: EVIDENCE BASED REHABILITATION AND RETURN TO PLAY

    PubMed Central

    O'Brien, Luke T.; LaPrade, Robert F.

    2016-01-01

    The medial collateral ligament is the most commonly injured ligament of the knee, with injury generally sustained in the athletic population as a result of valgus contact with or without tibial external rotation. The capacity of the medial collateral ligament to heal has been demonstrated in both laboratory and clinical studies; however, complete ruptures heal less consistently and may result in persistent instability. When operative intervention is deemed necessary, anatomical medial knee reconstruction is recommended. Post-operative rehabilitation focuses on early motion and the return of normal neuromuscular firing patterns with progression based on attainment of specific phase criteria and goals. The purpose of this clinical commentary is to discuss the determinants of phase progression and the importance of objectively assessing readiness for advancement that is consistent with post-operative healing. Additional tests and validated measures to assess readiness for sport are also presented. Level of Evidence 5 PMID:27999730

  4. CT-angiographic demonstration of hepatic collateral pathways due to superior vena cava obstruction in Behçet disease.

    PubMed

    Temizöz, Osman; Genchellac, Hakan; Yekeler, Ensar; Demir, Mustafa Kemal; Unlü, Ercüment; Ozdemir, Hüseyin

    2010-12-01

    Behçet disease (BD) is a chronic multisystemic inflammatory disorder, mainly characterized by recurrent oral and genital ulcers, skin lesions, and uveitis. Large vein thrombosis in BD is unusual; when present, it is most frequently seen in the inferior or superior vena cava (SVC). The authors describe an unusual hepatic pseudolesion caused by abnormal focal enhancement through collateral pathways to the liver in two BD patients with SVC occlusion on three-dimensional multi-detector computed tomography, using volume rendering and maximum intensity projection techniques. BD should be suspected in patients presenting a focal increased hepatic enhancement area with collaterals caused by occlusion of the SVC without evidence of a hypercoagulable state or malignant mediastinal or thoracic venous inlet obstruction.

  5. Abundances in A-type Horizontal Branch Stars

    NASA Astrophysics Data System (ADS)

    Wilhelm, R.; Smith, V. V.

    1998-12-01

    As part of a program to explore correlations between abundance anomilies and physical parameters (e.g. Teff, vsini) in horizontal branch stars, we present preliminary results from high-resolution (R ~ 18,000) spectral observations of a small sample of A-type, horizontal branch stars. The sample was obtained using the 2.1m telescope and Sandiford Echelle at McDonald Observatory. A total of six standard FHB stars were observed including two, HD 130095 and HD 167105, which have been previously shown by Adleman and Philip to posses anomalously low [Ca/Fe] values. We have also obtained observations of eight of the brighter (B = 11.5-12.5) FHB stars from the HK objective-prism survey and two BHB stars from the globular cluster, M4. We will present abundance results that include [Ca/Fe], [Mg/Fe], and vsini values for the sample along with O and Na results for the two M4 stars. Our findings will be compared to previously published results for cluster BHB and field HB stars.

  6. A common variant of endothelial nitric oxide synthase (Glu298Asp) is associated with collateral development in patients with chronic coronary occlusions

    PubMed Central

    Lamblin, Nicolas; Cuilleret, François J; Helbecque, Nicole; Dallongeville, Jean; Lablanche, Jean-Marc; Amouyel, Philippe; Bauters, Christophe; Van Belle, Eric

    2005-01-01

    Background Experimental studies support an important role for endothelial nitric oxide synthase (eNOS) in the regulation of angiogenesis. In humans, a common polymorphism exists in the eNOS gene that results in the conversion of glutamate to aspartate for codon 298. In vitro and in vivo studies have suggested a decreased NOS activity in patients with the Asp298 variant. We hypothesized that a genetic-mediated decreased eNOS activity may limit collateral development in patients with chronic coronary occlusions. Methods We selected 291 consecutive patients who underwent coronary angiography and who had at least one chronic (>15 days) total coronary occlusion. Collateral development was graded angiographically using two different methods: the collateral flow grade and the recipient filling grade. Genomic DNA was extracted from white blood cells and genotyping was performed using previously published techniques. Results Collateral development was lower in patients carrying the Asp298 variant than in Glu-Glu homozygotes (collateral flow grade: 2.64 ± 0.08 and 2.89 ± 0.08, respectively, p = 0.04; recipient filling grade: 3.00 ± 0.08 and 3.24 ± 0.07, respectively, p = 0.04). By multivariable analysis, three variables were independently associated with the collateral flow grade: female gender, smoking, and the Asp298 variant (p = 0.03) while the Asp298 variant was the sole variable independently associated with the recipient filling grade (p = 0.03). Conclusion Collateral development is lower in patients with the Asp298 variant. This may be explained by the decreased NOS activity in patients with the Asp298 variant. Further studies will have to determine whether increasing eNOS activity in humans is associated with coronary collateral development. PMID:16164743

  7. Cutaneous collateral axonal sprouting re-innervates the skin component and restores sensation of denervated Swine osteomyocutaneous alloflaps.

    PubMed

    Ibrahim, Zuhaib; Ebenezer, Gigi; Christensen, Joani M; Sarhane, Karim A; Hauer, Peter; Cooney, Damon S; Sacks, Justin M; Schneeberger, Stefan; Lee, W P Andrew; Polydefkis, Michael; Brandacher, Gerald

    2013-01-01

    Reconstructive transplantation such as extremity and face transplantation is a viable treatment option for select patients with devastating tissue loss. Sensorimotor recovery is a critical determinant of overall success of such transplants. Although motor function recovery has been extensively studied, mechanisms of sensory re-innervation are not well established. Recent clinical reports of face transplants confirm progressive sensory improvement even in cases where optimal repair of sensory nerves was not achieved. Two forms of sensory nerve regeneration are known. In regenerative sprouting, axonal outgrowth occurs from the transected nerve stump while in collateral sprouting, reinnervation of denervated tissue occurs through growth of uninjured axons into the denervated tissue. The latter mechanism may be more important in settings where transected sensory nerves cannot be re-apposed. In this study, denervated osteomyocutaneous alloflaps (hind- limb transplants) from Major Histocompatibility Complex (MHC)-defined MGH miniature swine were performed to specifically evaluate collateral axonal sprouting for cutaneous sensory re-innervation. The skin component of the flap was externalized and serial skin sections extending from native skin to the grafted flap were biopsied. In order to visualize regenerating axonal structures in the dermis and epidermis, 50 um frozen sections were immunostained against axonal and Schwann cell markers. In all alloflaps, collateral axonal sprouts from adjacent recipient skin extended into the denervated skin component along the dermal-epidermal junction from the periphery towards the center. On day 100 post-transplant, regenerating sprouts reached 0.5 cm into the flap centripetally. Eight months following transplant, epidermal fibers were visualized 1.5 cm from the margin (rate of regeneration 0.06 mm per day). All animals had pinprick sensation in the periphery of the transplanted skin within 3 months post-transplant. Restoration of

  8. Cutaneous Collateral Axonal Sprouting Re-Innervates the Skin Component and Restores Sensation of Denervated Swine Osteomyocutaneous Alloflaps

    PubMed Central

    Ibrahim, Zuhaib; Ebenezer, Gigi; Christensen, Joani M.; Sarhane, Karim A.; Hauer, Peter; Cooney, Damon S.; Sacks, Justin M.; Schneeberger, Stefan; Lee, W. P. Andrew

    2013-01-01

    Reconstructive transplantation such as extremity and face transplantation is a viable treatment option for select patients with devastating tissue loss. Sensorimotor recovery is a critical determinant of overall success of such transplants. Although motor function recovery has been extensively studied, mechanisms of sensory re-innervation are not well established. Recent clinical reports of face transplants confirm progressive sensory improvement even in cases where optimal repair of sensory nerves was not achieved. Two forms of sensory nerve regeneration are known. In regenerative sprouting, axonal outgrowth occurs from the transected nerve stump while in collateral sprouting, reinnervation of denervated tissue occurs through growth of uninjured axons into the denervated tissue. The latter mechanism may be more important in settings where transected sensory nerves cannot be re-apposed. In this study, denervated osteomyocutaneous alloflaps (hind- limb transplants) from Major Histocompatibility Complex (MHC)-defined MGH miniature swine were performed to specifically evaluate collateral axonal sprouting for cutaneous sensory re-innervation. The skin component of the flap was externalized and serial skin sections extending from native skin to the grafted flap were biopsied. In order to visualize regenerating axonal structures in the dermis and epidermis, 50um frozen sections were immunostained against axonal and Schwann cell markers. In all alloflaps, collateral axonal sprouts from adjacent recipient skin extended into the denervated skin component along the dermal-epidermal junction from the periphery towards the center. On day 100 post-transplant, regenerating sprouts reached 0.5 cm into the flap centripetally. Eight months following transplant, epidermal fibers were visualized 1.5 cm from the margin (rate of regeneration 0.06 mm per day). All animals had pinprick sensation in the periphery of the transplanted skin within 3 months post-transplant. Restoration of

  9. Exercise training-enhanced, endothelium-dependent dilation mediated by altered regulation of BKCa channels in collateral-dependent porcine coronary arterioles

    PubMed Central

    Xie, Wei; Parker, Janet L.; Heaps, Cristine L.

    2012-01-01

    Objective Test the hypothesis that exercise training increases the contribution of large-conductance, Ca2+-dependent K+ (BKCa) channels to endothelium-mediated dilation in coronary arterioles from collateral-dependent myocardial regions of chronically occluded pig hearts and may function downstream of H2O2. Methods An ameroid constrictor was placed around the proximal left circumflex coronary artery to induce gradual occlusion in Yucatan miniature swine. Eight weeks postoperatively, pigs were randomly assigned to sedentary or exercise training (treadmill; 14 wk) regimens. Results Exercise training significantly enhanced bradykinin-mediated dilation in collateral-dependent arterioles (~125 μm diameter) compared with sedentary pigs. The BKCa-channel blocker, iberiotoxin alone or in combination with the H2O2 scavenger, polyethylene glycol catalase, reversed exercise training-enhanced dilation in collateral-dependent arterioles. Iberiotoxin-sensitive whole-cell K+ currents (i.e., BKCa-channel currents) were not different between smooth muscle cells of nonoccluded and collateral-dependent arterioles of sedentary and exercise trained groups. Conclusions These data provide evidence that BKCa-channel activity contributes to exercise training-enhanced endothelium-dependent dilation in collateral-dependent coronary arterioles despite no change in smooth muscle BKCa-channel current. Taken together, our findings suggest that a component of the bradykinin signaling pathway, which stimulates BKCa channels, is enhanced by exercise training in collateral-dependent arterioles and suggest a potential role for H2O2 as the mediator. PMID:23002811

  10. Collateral damage to marine and terrestrial ecosystems from Yankee whaling in the 19th century.

    PubMed

    Drew, Joshua; López, Elora H; Gill, Lucy; McKeon, Mallory; Miller, Nathan; Steinberg, Madeline; Shen, Christa; McClenachan, Loren

    2016-11-01

    Yankee whalers of the 19th century had major impacts on populations of large whales, but these leviathans were not the only taxa targeted. Here, we describe the "collateral damage," the opportunistic or targeted taking of nongreat whale species by the American whaling industry. Using data from 5,064 records from 79 whaling logs occurring between 1840 and 1901, we show that Yankee whalers captured 5,255 animals across three large ocean basins from 32 different taxonomic categories, including a wide range of marine and terrestrial species. The taxa with the greatest number of individuals captured were walruses (Odobenus rosmarus), ducks (family Anatidae), and cod (Gadus sp.). By biomass, the most captured species were walruses, grampus (a poorly defined group within Odontoceti), and seals (family Otariidae). The whalers captured over 2.4 million kg of nongreat whale meat equaling approximately 34 kg of meat per ship per day at sea. The species and areas targeted shifted over time in response to overexploitation of whale populations, with likely intensive local impacts on terrestrial species associated with multiyear whaling camps. Our results show that the ecosystem impacts of whaling reverberated on both marine and coastal environments.

  11. Effect of sulfated glycosaminoglycan digestion on the transverse permeability of medial collateral ligament.

    PubMed

    Henninger, Heath B; Underwood, Clayton J; Ateshian, Gerard A; Weiss, Jeffrey A

    2010-09-17

    Dermatan and chondroitin sulfate glycosaminoglycans (GAGs) comprise over 90% of the GAG content in ligament. Studies of their mechanical contribution to soft tissues have reported conflicting results. Measuring the transient compressive response and biphasic material parameters of the tissue may elucidate the contributions of GAGs to the viscoelastic response to deformation. The hypotheses of the current study were that digestion of sulfated GAGs would decrease compressive stress and aggregate modulus while increasing the permeability of porcine medial collateral ligament (MCL). Confined compression stress relaxation experiments were carried out on porcine MCL and tissue treated with chondroitinase ABC (ChABC). Results were fit to a biphasic constitutive model to derive permeability and aggregate modulus. Bovine articular cartilage was used as a benchmark tissue to verify that the apparatus provided reliable results. GAG digestion removed up to 88% of sulfated GAGs from the ligament. Removal of sulfated GAGs increased the permeability of porcine MCL nearly 6-fold versus control tissues. Peak stress decreased significantly. Bovine articular cartilage exhibited the typical reduction of GAG content and resultant decreases in stress and modulus and increases in permeability with ChABC digestion. Given the relatively small amount of GAG in ligament (<1% of tissue dry weight) and the significant change in peak stress and permeability upon removal of GAGs, sulfated GAGs may play a significant role in maintaining the apposition of collagen fibrils in the transverse direction, thus supporting dynamic compressive loads experienced by the ligament during complex joint motion.

  12. Juvenile Arrest and Collateral Educational Damage in the Transition to Adulthood

    PubMed Central

    Kirk, David S.; Sampson, Robert J.

    2014-01-01

    Official sanctioning of students by the criminal justice system is a long-hypothesized source of educational disadvantage, but its explanatory status remains unresolved. Few studies of the educational consequences of a criminal record account for alternative explanations such as low self-control, lack of parental supervision, deviant peers, and neighborhood disadvantage. Moreover, virtually no research on the effect of a criminal record has examined the “black box” of mediating mechanisms or the consequence of arrest for postsecondary educational attainment. Analyzing longitudinal data with multiple and independent assessments of theoretically relevant domains, this paper estimates the direct effect of arrest on later high school dropout and college enrollment for adolescents with otherwise equivalent neighborhood, school, family, peer, and individual characteristics as well as similar frequency of criminal offending. We present evidence that arrest has a substantively large and robust impact on dropping out of high school among Chicago public school students. We also find a significant gap in four-year college enrollment between arrested and otherwise similar youth without a criminal record. We assess intervening mechanisms hypothesized to explain the process by which arrest disrupts the schooling process, and, in turn, produces collateral educational damage. The results imply that institutional responses and disruptions in students’ educational trajectories, rather than social psychological factors, are responsible for the arrest-education link. PMID:25309003

  13. Treatment of the ulnar nerve for overhead throwing athletes undergoing ulnar collateral ligament reconstruction

    PubMed Central

    Conti, Matthew S; Camp, Christopher L; Elattrache, Neal S; Altchek, David W; Dines, Joshua S

    2016-01-01

    Ulnar nerve (UN) injuries are a common complaint amongst overhead athletes. The UN is strained during periods of extreme valgus stress at the elbow, especially in the late-cocking and early acceleration phases of throwing. Although early ulnar collateral ligament (UCL) reconstruction techniques frequently included routine submuscular UN transposition, this is becoming less common with more modern techniques. We review the recent literature on the sites of UN compression, techniques to evaluate the UN nerve, and treatment of UN pathology in the overhead athlete. We also discuss our preferred techniques for selective decompression and anterior transposition of the UN when indicated. More recent studies support the use of UN transpositions only when there are specific preoperative symptoms. Athletes with isolated ulnar neuropathy are increasingly being treated with subcutaneous anterior transposition of the nerve rather than submuscular transposition. When ulnar neuropathy occurs with UCL insufficiency, adoption of the muscle-splitting approach for UCL reconstructions, as well as using a subcutaneous UN transposition have led to fewer postoperative complications and improved outcomes. Prudent handling of the UN in addition to appropriate surgical technique can lead to a high percentage of athletes who return to competitive sports following surgery for ulnar neuropathy. PMID:27795946

  14. As we age: Does slippage of quality control in the immune system lead to collateral damage?

    PubMed

    Müller, Ludmila; Pawelec, Graham

    2015-09-01

    The vertebrate adaptive immune system is remarkable for its possession of a very broad range of antigen receptors imbuing the system with exquisite specificity, in addition to the phagocytic and inflammatory cells of the innate system shared with invertebrates. This system requires strict control both at the level of the generation the cells carrying these receptors and at the level of their activation and effector function mediation in order to avoid autoimmunity and mitigate immune pathology. Thus, quality control checkpoints are built into the system at multiple nodes in the response, relying on clonal selection and regulatory networks to maximize pathogen-directed effects and minimize collateral tissue damage. However, these checkpoints are compromised with age, resulting in poorer immune control manifesting as tissue-damaging autoimmune and inflammatory phenomena which can cause widespread systemic disease, paradoxically compounding the problems associated with increased susceptibility to infectious disease and possibly cancer in the elderly. Better understanding the reasons for slippage of immune control will pave the way for developing rational strategies for interventions to maintain appropriate immunity while reducing immunopathology.

  15. Gap junctions of the medial collateral ligament: structure, distribution, associations and function

    PubMed Central

    Chi, Simon S; Rattner, JB; Sciore, Paul; Boorman, Richard; Lo, Ian KY

    2005-01-01

    Ligaments are composed of two major components: cells and extracellular matrix. The cells express gap junction proteins and are arranged into a series of rows that traverse the tissue, suggesting that all the cells of the tissue are functionally interconnected. The results of our study demonstrate that medial collateral ligament (MCL) cells do not have a uniform fusiform morphology or placement along a row of cells as previously suggested, but rather display a complex placement and form that weaves within the collagen matrix in a manner that is far more extensive and complex than previously appreciated. Within this morphological context, we find that MCL cells in vivo contain functional gap junctions (verified using fluorescence recovery after photobleaching) that are localized to sites of close cell–cell contact, and this pattern imparts or reflects a bipolarity inherent to each cell. When we studied ligament cells in conventional tissue culture we found that this bipolarity is lost, and the placement of gap junctions and their related proteins, as well as general cell morphology, is also altered. Finally, our study demonstrates, for the first time, that in addition to gap junctions, adherens junctions and desmosomes are also expressed by MCL cells both in vivo and in vitro and map to sites of cell–cell contact. PMID:16050901

  16. Purkinje Cell Axon Collaterals Terminate on Cat-301+ Neurons in Macaca Monkey Cerebellum

    PubMed Central

    Crook, J.D.; Hendrickson, A.; Erickson, A.; Possin, D.; Robinson, F.R.

    2008-01-01

    The monoclonal antibody Cat-301 identifies perineuronal nets around specific neuronal types, including those in the cerebellum. This report finds in adult Macaca monkey that Basket cells in the deep molecular layer; granule cell layer (GCL) interneurons including Lugaro cells; large neurons in the foliar white matter (WM); and deep cerebellar nuclei (DCN) neurons contain subsets of Cat-301+ cells. Most Cat-301+ GCL interneurons are glycine+ and all are densely innervated by a meshwork of calbindin+/GAD+ Purkinje cell collaterals and their synapses. DCN and WM Cat-301+ neurons also receive a similar but less dense innervation. Due to the heavy labeling of adjacent Purkinje cell dendrites, the innervation of Cat-301+ Basket cells was less certain. These findings suggest that several complex feedback circuits from Purkinje cell to cerebellar interneurons exist in primate cerebellum whose function needs to be investigated. Cat-301 labeling begins postnatally in WM and DCN, but remains sparse until at least 3 months of age. Because the appearance of perineuronal nets is associated with maturation of synaptic circuits, this suggests that the Purkinje cell feedback circuits develop for some time after birth. PMID:17936513

  17. Biologic Augmentation of the Ulnar Collateral Ligament in the Elbow of a Professional Baseball Pitcher

    PubMed Central

    Hoffman, James K.; Protzman, Nicole M.; Malhotra, Amit D.

    2015-01-01

    Tears of the ulnar collateral ligament (UCL) of the elbow are common injuries in overhead athletes. Although surgical reconstruction of the UCL has improved outcomes, not all athletes return to their previous level of competition and when this goal is achieved, the time required averages one to two years. Therefore, additional techniques are needed to further improve return to play and the rate of return to play in overhead athletes. A construct comprising a dermal allograft, platelet rich plasma (PRP), and mesenchymal stem cells (MSCs) has been shown to successfully improve healing in the rotator cuff. Given the promising provisional findings, we postulated that this construct could also improve healing if applied to the UCL. Therefore, the purpose of the present report was to examine the feasibility of utilizing a dermal allograft, PRP, and MSC construct to augment UCL reconstruction in a professional baseball pitcher. No complications were encountered. Although limited to minimal follow-up, the patient has demonstrated excellent progress and has returned to activity. PMID:26240769

  18. Physical examination and imaging of medial collateral ligament and posteromedial corner of the knee.

    PubMed

    Craft, Jason A; Kurzweil, Peter R

    2015-06-01

    The medial collateral ligament (MCL) is the most commonly injured knee ligament. Most will heal well with nonoperative treatment. However, not all medial knee injuries are the same. A detailed physical examination can help determine the severity of the medial-sided injury. When combined with advanced imaging, the examination will delineate damage to associated medial knee structures, including the location of MCL damage, posteromedial capsule injuries, and combined cruciate injuries. Failure to recognize MCL injuries that may be prone to chronic laxity can lead to significant disability, joint damage, and failure of concomitant cruciate ligament reconstructions. Magnetic resonance imaging is the mainstay of diagnostic imaging, with coronal sequences allowing full assessment of the MCL complex. Tangential views aid in the diagnosis of concomitant injuries. Stress radiography can play a role in evaluating MCL healing and subtle chronic laxity. Ultrasonography is also gaining acceptance as a means to assess MCL injuries. Use of a detailed examination and advanced imaging will allow optimal treatment of medial knee injuries and improve clinical outcomes.

  19. Branch architecture, light interception and crown development in saplings of a plagiotropically branching tropical tree, Polyalthia jenkinsii (Annonaceae).

    PubMed

    Osada, Noriyuki; Takeda, Hiroshi

    2003-01-01

    To investigate crown development patterns, branch architecture, branch-level light interception, and leaf and branch dynamics were studied in saplings of a plagiotropically branching tree species, Polyalthia jenkinsii Hk. f. & Thoms. (Annonaceae) in a Malaysian rain forest. Lengths of branches and parts of the branches lacking leaves ('bare' branches) were smaller in upper branches than in lower branches within crowns, whereas lengths of 'leafy' parts and the number of leaves per branch were larger in intermediate than in upper and lower branches. Maximum diffuse light absorption (DLA) of individual leaves was not related to sapling height or branch position within crowns, whereas minimum DLA was lower in tall saplings. Accordingly, branch-level light interception was higher in intermediate than in upper and lower branches. The leaf production rate was higher and leaf loss rate was smaller in upper than in intermediate and lower branches. Moreover, the branch production rate of new first-order branches was larger in the upper crowns. Thus, leaf and branch dynamics do not correspond to branch-level light interception in the different canopy zones. As a result of architectural constraints, branches at different vertical positions experience predictable light microenvironments in plagiotropic species. Accordingly, this pattern of carbon allocation among branches might be particularly important for growth and crown development in plagiotropic species.

  20. 77 FR 60988 - Advisory Bulletin on Collateralization of Advances and Other Credit Products Provided by Federal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-05

    ... Counsel, Neil.Crowley@fhfa.gov , (202) 649-3055; Joseph A. McKenzie, Associate Director, Division of Bank Regulation, Bank Analysis Branch, Joseph.McKenzie@fhfa.gov , (202) 649-3270; or Thomas Doolittle, Senior... Home Loan Banks to Insurance Company Members AGENCY: Federal Housing Finance Agency. ACTION:...

  1. Tillering and panicle branching genes in rice.

    PubMed

    Liang, Wei-hong; Shang, Fei; Lin, Qun-ting; Lou, Chen; Zhang, Jing

    2014-03-01

    Rice (Oryza sativa L.) is one of the most important staple food crops in the world, and rice tillering and panicle branching are important traits determining grain yield. Since the gene MONOCULM 1 (MOC 1) was first characterized as a key regulator in controlling rice tillering and branching, great progress has been achieved in identifying important genes associated with grain yield, elucidating the genetic basis of yield-related traits. Some of these important genes were shown to be applicable for molecular breeding of high-yielding rice. This review focuses on recent advances, with emphasis on rice tillering and panicle branching genes, and their regulatory networks.

  2. Disassortativity of random critical branching trees.

    PubMed

    Kim, J S; Kahng, B; Kim, D

    2009-06-01

    Random critical branching trees (CBTs) are generated by the multiplicative branching process, where the branching number is determined stochastically, independent of the degree of their ancestor. Here we show analytically that despite this stochastic independence, there exists the degree-degree correlation (DDC) in the CBT and it is disassortative. Moreover, the skeletons of fractal networks, the maximum spanning trees formed by the edge betweenness centrality, behave similarly to the CBT in the DDC. This analytic solution and observation support the argument that the fractal scaling in complex networks originates from the disassortativity in the DDC.

  3. Applied Aeroscience and CFD Branch Overview

    NASA Technical Reports Server (NTRS)

    LeBeau, Gerald J.; Kirk, Benjamin S.

    2014-01-01

    The principal mission of NASA Johnson Space Center is Human Spaceflight. In support of the mission the Applied Aeroscience and CFD Branch has several technical competencies that include aerodynamic characterization, aerothermodynamic heating, rarefied gas dynamics, and decelerator (parachute) systems.

  4. Sharing Fiscal Information: A Legislative Branch View.

    ERIC Educational Resources Information Center

    Rivlin, Alice M.

    1978-01-01

    Decisions regarding budget matters are complex; therefore, information sharing between the executive and legislative branches is helpful and necessary. Budget reforms have been initiated, but future trends indicate the need for flexibility and revision of information pathways. (MBR)

  5. FY 1990 Applied Sciences Branch annual report

    SciTech Connect

    Keyes, B.M.; Dippo, P.C.

    1991-11-01

    The Applied Sciences Branch actively supports the advancement of DOE/SERI goals for the development and implementation of the solar photovoltaic technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility which is capable of providing information on the full range of photovoltaic components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of photovoltaic technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. This report contains information on surface and interface analysis, materials characterization, development, electro-optical characterization module testing and performance, surface interactions and FTIR spectroscopy.

  6. Code 672 observational science branch computer networks

    NASA Technical Reports Server (NTRS)

    Hancock, D. W.; Shirk, H. G.

    1988-01-01

    In general, networking increases productivity due to the speed of transmission, easy access to remote computers, ability to share files, and increased availability of peripherals. Two different networks within the Observational Science Branch are described in detail.

  7. Overview of the Advanced High Frequency Branch

    NASA Technical Reports Server (NTRS)

    Miranda, Felix A.

    2015-01-01

    This presentation provides an overview of the competencies, selected areas of research and technology development activities, and current external collaborative efforts of the NASA Glenn Research Center's Advanced High Frequency Branch.

  8. Residence times of branching diffusion processes

    NASA Astrophysics Data System (ADS)

    Dumonteil, E.; Mazzolo, A.

    2016-07-01

    The residence time of a branching Brownian process is the amount of time that the mother particle and all its descendants spend inside a domain. Using the Feynman-Kac formalism, we derive the residence-time equation as well as the equations for its moments for a branching diffusion process with an arbitrary number of descendants. This general approach is illustrated with simple examples in free space and in confined geometries where explicit formulas for the moments are obtained within the long time limit. In particular, we study in detail the influence of the branching mechanism on those moments. The present approach can also be applied to investigate other additive functionals of branching Brownian process.

  9. Soils of Walker Branch Watershed

    SciTech Connect

    Lietzke, D.A.

    1994-01-01

    The soil survey of Walker Branch Watershed (WBW) utilized the most up-to-date knowledge of soils, geology, and geohydrology in building the soils data base needed to reinterpret past research and to begin new research in the watershed. The soils of WBW were also compared with soils mapped elsewhere along Chestnut Ridge on the Oak Ridge Reservation to (1) establish whether knowledge obtained elsewhere could be used within the watershed, (2) determine whether there were any soils restricted to the watershed, and (3) evaluate geologic formation lateral variability. Soils, surficial geology, and geomorphology were mapped at a scale of 1:1200 using a paper base map having 2-ft contour intervals. Most of the contours seemed to reasonably represent actual landform configurations, except for dense wooded areas. For example, the very large dolines or sinkholes were shown on the contour base map, but numerous smaller ones were not. In addition, small drainageways and gullies were often not shown. These often small but important features were located approximately as soil mapping progressed. WBW is underlain by dolostones of the Knox Group, but only a very small part of the surface area contains outcroppings of rock and most outcrops were located in the lower part. Soil mapping revealed the presence of both ancient alluvium and ancient colluvium deposits, not recognized in previous soil surveys, that have been preserved in high-elevation stable portions of present-day landforms. An erosional geomorphic process of topographic inversion requiring several millions of years within the Pleistocene is necessary to bring about the degree of inversion that is expressed in the watershed. Indeed, some of these ancient alluvial and colluvial remnants may date back into the Tertiary. Also evident in the watershed, and preserved in the broad, nearly level bottoms of dolines, are multiple deposits of silty material either devoid or nearly devoid of coarse fragments. Recent research

  10. Title Sheet, National Home for Disabled Volunteer Soldiers, Northwestern Branch ...

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

    Title Sheet, National Home for Disabled Volunteer Soldiers, Northwestern Branch - National Home for Disabled Volunteer Soldiers, Northwestern Branch, 5000 West National Avenue, Milwaukee, Milwaukee County, WI

  11. Should We Limit Innings Pitched Following Ulnar Collateral Ligament Reconstruction in Major League Baseball Pitchers?

    PubMed Central

    Erickson, Brandon J.; Cvetanovich, Gregory; Bach, Bernard R.; Bush-Joseph, Charles A.; Verma, Nikhil N.; Romeo, Anthony A.

    2016-01-01

    Objectives: Background: Ulnar collateral ligament reconstruction (UCLR) has become a common procedure amongst major league baseball (MLB) pitchers. It is unclear if a limit on innings pitched following UCLR should be instituted to prevent revision UCLR. Purpose: To determine whether the number of innings pitched or number of pitches thrown in the first full season following UCLR, as well as the pitcher’s overall MLB career, correlated with need for a revision UCLR Hypothesis: Number of innings pitched and number of pitches thrown following UCLR will not affect whether a pitcher undergoes a revision UCLR. Methods: Methods: All MLB pitchers between 1974-2015 who pitched at least one full season following UCLR were included. Pitch counts and innings pitched for the first full season following UCLR as well as total pitch count and total innings pitched following UCLR were recorded. Pitch counts and innings pitched were compared amongst players who required revision UCLR and those who did not. Results: Results: Overall, 154 pitchers were included. Of these, 135 pitchers did not require revision UCLR while 19 underwent revision UCLR. No significant difference existed between pitchers who underwent revision UCLR and those who did not in: number of innings pitched in the season following UCLR (p=0.9016), number of pitches thrown in the season following UCLR (p=0.7337), number of innings pitched in the pitcher’s career following UCLR (p=0.6945), and number of pitches thrown in the pitcher’s career following UCLR (p=0.4789). Furthermore, no difference existed in revision rate between pitchers who pitched more or less than 180 innings in the first full season following UCLR (p=0.6678). Conclusion: Conclusion: The number of innings pitched and number of pitches thrown in the first full season as well as over a player’s career following UCLR does not appear to increase a player’s risk of revision UCLR.

  12. Collateral transgression of planetary boundaries due to climate engineering by terrestrial carbon dioxide removal

    NASA Astrophysics Data System (ADS)

    Heck, Vera; Donges, Jonathan F.; Lucht, Wolfgang

    2016-10-01

    The planetary boundaries framework provides guidelines for defining thresholds in environmental variables. Their transgression is likely to result in a shift in Earth system functioning away from the relatively stable Holocene state. As the climate system is approaching critical thresholds of atmospheric carbon, several climate engineering methods are discussed, aiming at a reduction of atmospheric carbon concentrations to control the Earth's energy balance. Terrestrial carbon dioxide removal (tCDR) via afforestation or bioenergy production with carbon capture and storage are part of most climate change mitigation scenarios that limit global warming to less than 2 °C. We analyse the co-evolutionary interaction of societal interventions via tCDR and the natural dynamics of the Earth's carbon cycle. Applying a conceptual modelling framework, we analyse how the degree of anticipation of the climate problem and the intensity of tCDR efforts with the aim of staying within a "safe" level of global warming might influence the state of the Earth system with respect to other carbon-related planetary boundaries. Within the scope of our approach, we show that societal management of atmospheric carbon via tCDR can lead to a collateral transgression of the planetary boundary of land system change. Our analysis indicates that the opportunities to remain in a desirable region within carbon-related planetary boundaries only exist for a small range of anticipation levels and depend critically on the underlying emission pathway. While tCDR has the potential to ensure the Earth system's persistence within a carbon-safe operating space under low-emission pathways, it is unlikely to succeed in a business-as-usual scenario.

  13. Mexico’s northern border conflict: collateral damage to health and human rights of vulnerable groups

    PubMed Central

    Beletsky, Leo; Martinez, Gustavo; Gaines, Tommi; Nguyen, Lucie; Lozada, Remedios; Rangel, Gudelia; Vera, Alicia; McCauley, Heather L.; Sorensen, Andrea; Strathdee, Steffanie A.

    2013-01-01

    Objective To compare distributions of human rights violations and disease risk; to juxtapose these patterns against demographic and structural environmental variables, and to formulate implications for structural interventions. Methods Female sex workers who inject drugs were surveyed in Tijuana and Ciudad Juarez, Mexico. Structured interviews and testing for sexually transmitted infections (STIs) were conducted (October 2008 to October 2009). Frequencies of individual and environmental factors, including police abuse, risk of HIV infection, and protective behaviors, were compared between sites using univariate logistic regression. Results Of 624 women, almost half reported police syringe confiscation despite syringes being legal; 55.6% reported extortion (past 6 months), with significantly higher proportions in Ciudad Juarez (P < 0.001). Reports of recent solicitation of sexual favors (28.5% in Tijuana, 36.5% in Ciudad Juarez, P = 0.04) and sexual abuse (15.7% in Tijuana, 18.3% in Ciudad Juarez) by police were commonplace. Prevalence of STIs was significantly lower in Tijuana than in Ciudad Juarez (64.2% and 83.4%, P < 0.001), paralleling the lower prevalence of sexual risk behaviors there. Ciudad Juarez respondents reported significantly higher median number of monthly clients (6.8 versus 1.5, P < 0.001) and lower median pay per sex act (US$ 10 versus US$ 20, P < 0.001) (in the past month). Relative to Tijuana, security deployment, especially the army’s presence, was perceived to have increased more in Ciudad Juarez in the past year (72.1% versus 59.2%, P = 0.001). Conclusions Collateral damage from police practices in the context of Mexico’s drug conflict may affect public health in the Northern Border Region. Itinerant officers may facilitate disease spread beyond the region. The urgency for mounting structural interventions is discussed. PMID:22767041

  14. GABA and Endocannabinoids Mediate Depotentiation of Schaffer Collateral Synapses Induced by Stimulation of Temperoammonic Inputs.

    PubMed

    Izumi, Yukitoshi; Zorumski, Charles F

    2016-01-01

    Long-term potentiation (LTP) of Schaffer collateral (SC) synapses in the hippocampus is thought to play a key role in episodic memory formation. Because the hippocampus is a shorter-term, limited capacity storage system, repeated bouts of learning and synaptic plasticity require that SC synapses reset to baseline at some point following LTP. We previously showed that repeated low frequency activation of temperoammonic (TA) inputs to the CA1 region depotentiates SC LTP without persistently altering basal transmission. This heterosynaptic depotentiation involves adenosine A1 receptors but not N-methyl-D-aspartate receptors, metabotropic glutamate receptors or L-type calcium channels. In the present study, we used rat hippocampal slices to explore other messengers contributing to TA-induced SC depotentiation, and provide evidence for the involvement of cannabinoid-1 and γ-aminobutyric acid (GABA) type-A receptors as more proximal signaling events leading to synaptic resetting, with A1 receptor activation serving as a downstream event. Surprisingly, we found that TA-induced SC depotentiation is independent of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)/kainate glutamate receptors. We also examined the involvement of mitogen-activated protein kinases (MAPKs), and found a role for extracellular-signal related kinase 1/2 and p38 MAPK, but not c-Jun-N-terminal kinase. These results indicate that low frequency stimulation of TA inputs to CA1 activates a complex signaling network that instructs SC synaptic resetting. The involvement of GABA and endocannabinoids suggest mechanisms that could contribute to cognitive dysfunction associated with substance abuse and neuropsychiatric disorders.

  15. Periventricular anastomosis in moyamoya disease: detecting fragile collateral vessels with MR angiography.

    PubMed

    Funaki, Takeshi; Takahashi, Jun C; Yoshida, Kazumichi; Takagi, Yasushi; Fushimi, Yasutaka; Kikuchi, Takayuki; Mineharu, Yohei; Okada, Tomohisa; Morimoto, Takaaki; Miyamoto, Susumu

    2016-06-01

    OBJECT The authors' aim in this paper was to determine whether periventricular anastomosis, a novel term for the abnormal collateral vessels typical of moyamoya disease, is reliably measured with MR angiography and is associated with intracranial hemorrhage. METHODS This cross-sectional study sampled consecutive patients with moyamoya disease or moyamoya syndrome at a single institution. Periventricular anastomoses were detected using MR angiography images reformatted as sliding-thin-slab maximum-intensity-projection coronal images and were scored according to 3 subtypes: lenticulostriate, thalamic, and choroidal types. The association between periventricular anastomosis and hemorrhagic presentation at onset was evaluated using multivariate analyses. RESULTS Of 136 eligible patients, 122 were analyzed. Eighteen (14.8%) patients presented with intracranial hemorrhage with neurological symptoms at onset. Intra- and interrater agreement for rating of the periventricular anastomosis score was good (κw = 0.65 and 0.70, respectively). The prevalence of hemorrhagic presentation increased with the periventricular anastomosis score: 2.8% for Score 0, 8.8% for Score 1, 18.9% for Score 2, and 46.7% for Score 3 (p < 0.01 for trend). Univariate analysis revealed that age (p = 0.02) and periventricular anastomosis score (p < 0.01) were factors tentatively associated with hemorrhagic presentation. The score remained statistically significant after adjustment for age (OR 3.38 [95% CI 1.84-7.00]). CONCLUSIONS The results suggest that periventricular anastomosis detected with MR angiography can be scored with good intra- and interrater reliability and is associated with hemorrhagic presentation at onset in moyamoya disease. The clinical utility of periventricular anastomosis as a predictor for hemorrhage should be validated in further prospective studies.

  16. Differential frequency-dependent antidromic resonance of the Schaffer collaterals and mossy fibers.

    PubMed

    Franco, Luis M; Beltrán, Jesús Q; Tapia, Jesús A; Ortiz, Franco; Manjarrez, Elías; Gutiérrez, Rafael

    2016-05-01

    To better understand information transfer along the hippocampal pathways and its plasticity, here we studied the antidromic responses of the dentate gyrus (DG) and CA3 to activation of the mossy fibers and Schaffer collaterals, respectively, in hippocampal slices from naïve and epileptic rats. We applied trains of 600 electrical stimuli at functionally meaningful frequencies (θ, β/γ and γ). The responses of the DG to θ frequency trains underwent rapid potentiation that lasted about 400 stimuli, after which they progressively returned to control value. At β/γ and γ frequencies, however, the initial potentiation was followed by a strong frequency-dependent depression within the first 50 stimuli. In kindled animals, the initial potentiation was stronger than in control preparations and the resonant phase at θ frequency lasted longer. In contrast, CA3 responses were exponentially depressed at all frequencies, but depression was significantly less intense at θ frequency in epileptic preparations. Failure of fibers to fire action potentials could account for some of the aforementioned characteristics, but waveforms of the intracellular action potentials also changed as the field responses did, i.e., half-duration and time-to-peak increased in both structures along the stimulation trains. Noteworthy, block of glutamate and GABA ionotropic receptors prevented resonance and reduced the depression of antidromic responses to β/γ and γ stimulation recorded in the DG, but not in CA3. We show that the different behavior in the information transfer along these pathways depends on the frequency at which action potentials are generated, excitability history and anatomical features, including myelination and tortuosity. In addition, the mossy fibers are endowed with ionotropic receptors and terminal active properties conferring them their sui generis non-passive antidromic responses.

  17. Collagen fibre arrangement and functional crimping pattern of the medial collateral ligament in the rat knee.

    PubMed

    Franchi, Marco; Quaranta, Marilisa; Macciocca, Maria; Leonardi, Luisa; Ottani, Vittoria; Bianchini, Paolo; Diaspro, Alberto; Ruggeri, Alessandro

    2010-12-01

    Ligaments have been described as multifascicular structures with collagen fibres cross-connecting to each other or running straight and parallel also showing a waviness or crimping pattern playing as a shock absorber/recoiling system during joint motions. A particular collagen array and crimping pattern in different ligaments may reflect different biomechanical roles and properties. The aim of the study was to relate the 3D collagen arrangement in the crimping pattern of the medial collateral ligament (MCL) to its functional role. The MCL is one of the most injured ligaments during sports activities and an experimental model to understand the rate, quality and composition of ligaments healing. A deep knowledge of structure-function relationship of collagen fibres array will improve the development of rehabilitation protocols and more appropriate exercises for recovery of functional activity. The rat MCL was analysed by polarized light microscopy, confocal laser microscopy and scanning electron microscopy (SEM). Histomorphometric analysis demonstrated that MCL crimps have a smaller base length versus other tendons. SEM observations demonstrated that collagen fibres showing few crimps were composed of fibrils intertwining and crossing one another in the outer region. Confocal laser analyses excluded a helical array of collagen fibres. By contrast, in the core portion, densely packed straight collagen fibres ran parallel to the main axis of the ligament being interrupted both by planar crimps, similar to tendon crimps, and by newly described right-handed twisted crimps. It is concluded that planar crimps could oppose or respond exclusively to tensional forces parallel to the main ligament axis, whereas the right-handed twisted crimps could better resist/respond to a complex of tensional/rotational forces within the ligament thus opposing to an external rotation of tibia.

  18. A biomechanical assessment to evaluate breed differences in normal porcine medial collateral ligaments.

    PubMed

    Germscheid, Niccole M; Thornton, Gail M; Hart, David A; Hildebrand, Kevin A

    2011-02-24

    Little information is available on the role of genetic factors and heredity in normal ligament behaviour and their ability to heal. Assessing these factors is challenging because of the lack of suitable animal models. Therefore, the purpose of this study was to develop a porcine model in order to evaluate and compare the biomechanical differences of normal medial collateral ligaments (MCLs) between Yorkshire (YK) and red Duroc (RD) breeds. It was hypothesized that biomechanical differences would not exist between normal YK and RD MCLs. Comparisons between porcine and human MCL were also made. A biomechanical testing apparatus and protocol specific to pig MCL were developed. Ligaments were subjected to cyclic and static creep tests and then elongated to failure. Pig MCL morphology, geometry, and low- and high-load mechanical behaviour were assessed. The custom-designed apparatus and protocol were sufficiently sensitive to detect mechanical property differences between breeds as well as inter-leg differences. The results reveal that porcine MCL is comparable in both shape and size to human MCL and exhibits similar structural and material failure properties, thus making it a feasible model. Comparisons between RD and YK breeds revealed that age-matched RD pigs weigh more, have larger MCL cross-sectional area, and have lower MCL failure stress than YK pigs. The effect of weight may have influenced MCL geometrical and biomechanical properties, and consequently, the differences observed may be due to breed type and/or animal weight. In conclusion, the pig serves as a suitable large animal model for genetic-related connective tissue studies.

  19. Diabetes Diminishes the Portal-Systemic Collateral Vascular Response to Vasopressin via Vasopressin Receptor and Gα Proteins Regulations in Cirrhotic Rats

    PubMed Central

    Lee, Jing-Yi; Huo, Teh-Ia; Wang, Sun-Sang; Lin, Han-Chieh; Chuang, Chiao-Lin; Lee, Shou-Dong

    2013-01-01

    Liver cirrhosis may lead to portal-systemic collateral formation and bleeding. The hemostatic effect is influenced by the response of collateral vessels to vasoconstrictors. Diabetes and glucose also influence vasoresponsiveness, but their net effect on collaterals remains unexplored. This study investigated the impact of diabetes or glucose application on portal-systemic collateral vasoresponsiveness to arginine vasopressin (AVP) in cirrhosis. Spraque-Dawley rats with bile duct ligation (BDL)-induced cirrhosis received vehicle (citrate buffer) or streptozotocin (diabetic, BDL/STZ). The in situ collateral perfusion was done after hemodynamic measurements: Both were perfused with Krebs solution, D-glucose, or D-glucose and NaF, with additional OPC-31260 for the BDL/STZ group. Splenorenal shunt vasopressin receptors and Gα proteins mRNA expressions were evaluated. The survival rate of cirrhotic rats was decreased by STZ injection. The collateral perfusion pressure changes to AVP were lower in STZ-injected groups, which were reversed by OPC-31260 (a V2R antagonist) and overcome by NaF (a G protein activator). The splenorenal shunt V2R mRNA expression was increased while Gα proteins mRNA expressions were decreased in BDL/STZ rats compared to BDL rats. The Gαq and Gα11 mRNA expressions also correlated with the maximal perfusion pressure changes to AVP. Diabetes diminished the portal-systemic collateral vascular response to AVP in rats with BDL-induced cirrhosis, probably via V2 receptor up-regulation and Gα proteins down-regulation. PMID:23874439

  20. Differential modulation of primary afferent depolarization of segmental and ascending intraspinal collaterals of single muscle afferents in the cat spinal cord.

    PubMed

    Rudomin, P; Lomelí, J; Quevedo, J

    2004-06-01

    We examined primary afferent depolarization (PAD) in the anesthetized cat elicited in 109 pairs of intraspinal collaterals of single group I afferents from the gastrocnemius nerve, one of the pair ending in the L3 segment, around the Clarke's column nuclei, and the other in the L6 segment within the intermediate zone. Tests for refractoriness were made to assess whether the responses produced by intraspinal stimulation in the L3 and L6 segments were due to activation of collaterals of the same afferent fiber. PAD in each collateral was estimated by independent computer-controlled measurement of the intraspinal current required to maintain a constant probability of antidromic firing. In most fibers, stimulation of the ipsilateral posterior biceps and semitendinosus (PBSt) nerve with trains of pulses maximal for group I afferents had a qualitatively similar effect but produced a larger PAD in the L6 than in the L3 collaterals. Stimulation of cutaneous nerves (sural and superficial peroneus) with single pulses and of the posterior articular nerve, the ipsilateral reticular formation, nucleus raphe magnus and contralateral motor cortex with trains of pulses often had qualitatively different effects. They could produce PAD and/or facilitate the PBSt-induced PAD in one collateral, and produce PAH and/or inhibit the PAD in the other collateral. These patterns could be changed in a differential manner by sensory or supraspinal conditioning stimulation. In summary, the present investigation suggests that the segmental and ascending collaterals of individual afferents are not fixed routes for information transmission, but parts of dynamic systems in which information transmitted to segmental reflex pathways and to Clarke's column neurons by common sources can be decoupled by sensory and descending inputs and funneled to specific targets according to the motor tasks to be performed.

  1. Northwestern Branch of Mangala Vallis

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 12 June 2002) The Science One of the many branches of the Mangala Vallis channel system is seen in this image. The water that likely carved the channels emerged from a huge graben or fracture almost 1000 km to the south. The THEMIS image shows where one of the channels exits the cratered highlands terrain onto the lowland plains. A bright scarp marks the transition between the two terrain types and demonstrates that in this location the highlands terrain is being eroded back. Note how the floor of the main channel appears to be at the same level as the lowland terrain, suggestive of a base level where erosion is no longer effective. Most of the steep slope faces in the image display darker slope streaks that are thought to be dust avalanche scars and indicate that a relatively thick mantle of dust is present in this region. Wind-sculpted ridges known as yardangs cover many of the surfaces throughout the area as shown by images from the Mars Global Surveyor mission. Most of them are at the limit of resolution in the THEMIS image but some are evident on the floor of the main channel at the point at which a smaller side channel enters. In this location they appear to extend right up to the base of the channel wall, giving the appearance that they are emerging from underneath the thick pile of material into which the channel is eroded. This suggests a geologic history in which a preexisting landscape of eroded yardangs was covered over by a thick pile of younger material that is now eroding back down to the original level. Alternatively, it is possible that the yardangs formed more recently at the abrupt transition between the channel floor and wall. More analysis is necessary to sort out the story. The Story This channel system is named 'Mangala,' the word for Mars in Sanskrit, a language of the Hindus of India that goes back more than 4,000 years, with written literature almost as long. Great epic tales have been written in this language, and Odyssey is

  2. Solutions for transients in arbitrarily branching cables: III. Voltage clamp problems.

    PubMed Central

    Major, G

    1993-01-01

    Branched cable voltage recording and voltage clamp analytical solutions derived in two previous papers are used to explore practical issues concerning voltage clamp. Single exponentials can be fitted reasonably well to the decay phase of clamped synaptic currents, although they contain many underlying components. The effective time constant depends on the fit interval. The smoothing effects on synaptic clamp currents of dendritic cables and series resistance are explored with a single cylinder + soma model, for inputs with different time courses. "Soma" and "cable" charging currents cannot be separated easily when the soma is much smaller than the dendrites. Subtractive soma capacitance compensation and series resistance compensation are discussed. In a hippocampal CA1 pyramidal neurone model, voltage control at most dendritic sites is extremely poor. Parameter dependencies are illustrated. The effects of series resistance compound those of dendritic cables and depend on the "effective capacitance" of the cell. Plausible combinations of parameters can cause order-of-magnitude distortions to clamp current waveform measures of simulated Schaeffer collateral inputs. These voltage clamp problems are unlikely to be solved by the use of switch clamp methods. PMID:8369450

  3. Structure-Property Relationships for Branched Worm-Like Micelles

    NASA Astrophysics Data System (ADS)

    Beaucage, Gregory; Rai, Durgesh

    2013-03-01

    Micellar solutions can display a wide range of phase structure as a function of counter ion content, surfactant concentration, and the presence of ternary components. Under some conditions, common to consumer products, extended cylindrical structures that display persistence and other chain features of polymers are produced. These worm-like micelles (WLMs) can form branched structures that dynamically change under shear and even in quiescent conditions. The rheology of these branched WLMs is strongly dependent on migration of the branch points, and the dynamics of branch formation and removal. Persistence and other polymer-based descriptions are also of importance. We have recently developed a scattering model for branched polyolefins and other topologically complex materials that can quantify the branching density, branch length, branch functionality and the hyperbranch (branch-on-branch) content of polymers. This work is being extended to study branching in WLMs in work coupled with Ron Larson at UMich to predict rheological properties.

  4. Damping by branching: a bioinspiration from trees.

    PubMed

    Theckes, B; Langre, E de; Boutillon, X

    2011-12-01

    Man-made slender structures are known to be sensitive to high levels of vibration due to their flexibility which often cause irreversible damage. In nature, trees repeatedly endure large amplitudes of motion, mostly caused by strong climatic events, yet with minor or no damage in most cases. A new damping mechanism inspired by the architecture of trees is identified here and characterized in the simplest tree-like structure, a Y-shaped branched structure. Through analytical and numerical analyses of a simple two-degree-of-freedom model, branching is shown to be the key ingredient in this protective mechanism that we call damping-by-branching. It originates in the geometrical nonlinearities so that it is specifically efficient to damp out large amplitudes of motion. A more realistic model, using flexible beam approximation, shows that the mechanism is robust. Finally, two bioinspired architectures are analyzed, showing significant levels of damping achieved via branching with typically 30% of the energy being dissipated in one oscillation. This concept of damping-by-branching is of simple practical use in the design of very slender and flexible structures subjected to extreme dynamical loadings.

  5. Onyx, a New Liquid Embolic Material for Peripheral Interventions: Preliminary Experience in Aneurysm, Pseudoaneurysm, and Pulmonary Arteriovenous Malformation Embolization

    SciTech Connect

    Vanninen, Ritva L. Manninen, I.

    2007-04-15

    Purpose. To describe our preliminary experience with a new liquid embolization agent, Onyx, in peripheral interventions. Methods and results. We successfully treated two peripheral aneurysms (one in an internal iliac artery, one in a thoracic collateral artery of an aortic coarctation), two peripheral pseudoaneurysms (one in a lumbar artery, one in a renal artery), and one pulmonary arteriovenous malformation. Conclusion. Onyx is a promising alternative embolic material for peripheral interventions. It can be combined with coils in selected cases, and balloon catheters can be effectively used during slow injection of embolic material to control flow and protect the aneurysm neck.

  6. Collateral projection from the locus coeruleus to whisker-related sensory and motor brain regions of the rat.

    PubMed

    Lee, Sat-Byol; Beak, Suk K; Park, Seung H; Waterhouse, Barry D; Lee, Hyun S

    2009-06-01

    The primary goal of this study was to examine whether the locus coeruleus (LC) provides collateral projections to whisker-related, sensorimotor brain regions. After injections of retrograde tracers into the primary sensory (S1) barrel field/primary whisker motor (M1) cortices, ventroposteromedial (VPM)/ventrolateral (VL) thalamic nuclei, or principal sensory trigeminal (Pr5)/facial motor (Mo7) nuclei, the distribution of double-labeled neurons within the LC was examined. Our observations indicated that a large number of individual LC cells provided axon collaterals to S1-M1 or VPM-VL regions, whereas only a few projected to Pr5-Mo7 nuclei. The laterality and the distribution of dual-projecting LC neurons were as follows. 1) The neurons projecting to the S1-M1 cortices were predominantly ipsilateral (96% +/- 0.7%). Labeled neurons were located ventrally at the rostral pole but were evenly distributed along the dorsoventral aspect of the principal LC. 2) The cells projecting to the VPM-VL nuclei were bilateral, with ipsilateral (68% +/- 2.3%) dominance. Neurons were observed at the rostrocaudal extent of the LC, where the labeling was most pronounced at the ventral, principal LC. 3) The neurons projecting to the Pr5-Mo7 regions exhibited slightly contralateral (56% +/- 2.9%) dominance, where labeled cells were confined within the ventral margin of the principal subdivision. Taken together, the present observations demonstrate that each subdivision of the LC possesses a differential functional organization with respect to its collateral projection to whisker-related sensorimotor targets, suggesting that the nucleus might play a modulatory role in vibrissal sensorimotor integration that allows the guidance of behavioral action essential for the survival of the animal.

  7. Vascular endothelial growth factor and hypoxia-inducible factor-1α gene polymorphisms and coronary collateral formation in patients with coronary chronic total occlusions

    PubMed Central

    Amoah, Vincent; Wrigley, Benjamin; Holroyd, Eric; Smallwood, Andrew; Armesilla, Angel L; Nevill, Alan; Cotton, James

    2016-01-01

    Introduction: We evaluated the association between two single nucleotide polymorphisms of the vascular endothelial growth factor gene and one of the hypoxia-inducible factor-1α gene and the degree of coronary collateral formation in patients with a coronary chronic total occlusion. Methods: Totally, 98 patients with symptomatic coronary artery disease and a chronic total occlusion observed during coronary angiography were recruited. Genotyping of two vascular endothelial growth factor promoter single nucleotide polymorphisms (−152G>A and −165C>T) and the C1772T single nucleotide polymorphism of hypoxia-inducible factor-1α were performed using polymerase chain reaction and restriction fragment length polymorphism analysis. The presence and extent of collateral vessel filling was scored by blinded observers using the Rentrop grade. Results: We found no association between the vascular endothelial growth factor −152G>A, −165C>T and hypoxia-inducible factor-1α −1772C>T with the presence and filling of coronary collateral vessels. A history of percutaneous coronary intervention and transient ischaemic attack/cerebrovascular accident were associated with the presence of enhanced collateral vessel formation following binary logistic regression analysis. Conclusion: The study findings suggest that coronary collateral formation is not associated with the tested polymorphic variants of vascular endothelial growth factor and hypoxia-inducible factor-1α in patients with symptomatic coronary artery disease and the presence of a chronic total occlusion. PMID:27621802

  8. The Future of Washington's Branch Campuses. HECB Report on Branch Campus Development Plans-HB 2707

    ERIC Educational Resources Information Center

    Washington Higher Education Coordinating Board, 2005

    2005-01-01

    Washington's research university branch campuses were created in 1989 to increase opportunities for students in several regions of the state to complete their baccalaureate and graduate-level studies at public universities close to their homes. Currently, the University of Washington operates branch campuses in Bothell and Tacoma. The Bothell…

  9. Hyperintense ipsilateral cortical sulci on FLAIR imaging in carotid stenosis: ivy sign equivalent from enlarged leptomeningeal collaterals.

    PubMed

    Hacein-Bey, Lotfi; Mukundan, Govind; Shahi, Kavian; Chan, Hung; Tajlil, Ali T

    2014-01-01

    Fluid-attenuated inversion recovery (FLAIR) imaging provides high contrast between hyperintense lesions and normal tissue. Hyperintense structures in convexity sulci are commonly linked to abnormal cerebrospinal fluid composition, whether blood, protein, or infection. A patient with hemispheric transient ischemic attacks from severe carotid stenosis had hyperintense convexity sulci on FLAIR magnetic resonance imaging, interpreted as possible prior hemorrhage, making the patient ineligible for carotid stent reconstruction. Retrospective analysis revealed that hyperintense sulci were dilated leptomeningeal collaterals. In severe arterial disease causing cerebral hypoperfusion, dilated leptomeningeal vessels should be considered a cause for serpiginous hyperintense structures on FLAIR imaging, similar to the "ivy sign" described in moya-moya patients.

  10. MRI Predictors of Failure in Non-operative Management of Ulnar Collateral Ligament Injuries in Professional Baseball Pitchers

    PubMed Central

    Lynch, Thomas Sean; Frangiamore, Salvatore; Vaughn, Michael Derek; Soloff, Lonnie; Schickendantz, Mark S.

    2016-01-01

    Objectives: Ulnar collateral injuries (UCL) of the elbow are prevalent among professional baseball pitchers. The decision on initial operative versus nonoperative management of these injuries remains subjective in many cases, with reported success rates with nonoperative management ranging from 42 to 93% in professional throwing athletes. No studies to date have identified objective characteristics specific to success or failure of nonoperative intervention. The purpose of this study was to identify radiologic predictors for success or failure in nonoperative management of ulnar collateral ligament injuries in professional pitchers. Methods: A retrospective review of pitchers sustaining UCL injuries between 2006 and 2015 from one professional baseball organization (one major league team and all minor league teams included) was performed. UCL injuries were identified in 38 players based on clinical and radiographic findings. Six players underwent initial surgical intervention without attempted nonoperative intervention and were excluded from analysis. This left 32 (84%) professional pitchers who underwent an initial trail of nonoperative treatment for partial UCL tears. Success was defined as return to same level of play (RTSP) or higher for >1 year. Failure was defined as recurrent pain or weakness requiring surgical intervention after a minimum of 3 months’ rest when attempting a return to throw rehabilitation program. MRI findings were classified as high or low grade sprains, proximal or distal location of injury, and with or without the presence of concomitant chronic findings. Results: Of the 32 patients who underwent nonoperative management, 10 (36%) failed and required subsequent ligament reconstruction. Between the success and failure groups, there was no significant difference seen in total shoulder arc of motion (P=.7776), shoulder internal rotation deficit (P=.3846) or loss in elbow extension (P=.0644) at the time of injury. When comparing MRI findings

  11. Building Virtual Spaces for Children in the Digital Branch

    ERIC Educational Resources Information Center

    DuBroy, Michelle

    2010-01-01

    Purpose: A digital branch is just like a physical branch except that content is delivered digitally via the web. A digital branch has staff, a collection, a community, and a building. The purpose of this paper is to explore the concept of building individual spaces for different user groups, specifically children, within a digital branch.…

  12. Does Geographic Location Matter on the Prevalence of Ulnar Collateral Ligament Reconstruction in Collegiate Baseball Pitchers?

    PubMed Central

    Zaremski, Jason L.; Horodyski, MaryBeth; Donlan, Robert M.; Brisbane, Sonya Tang; Farmer, Kevin W.

    2015-01-01

    Background: There has been a significant amount of research in the prevention of throwing injuries. However, one area of research that is lacking is geographic location of play. Warm climates may permit year-round play and increased exposure to throwing arm injury risk. Hypotheses: (1) Pitchers from southern institutions would have greater rates of ulnar collateral ligament reconstruction (UCL-R) compared with pitchers from northern institutions. (2) Pitchers originating from high school teams in warm weather states would have a greater risk of undergoing UCL-R while in college. Study Design: Descriptive epidemiological study. Methods: This study was completed by reviewing publicly obtained records of male collegiate baseball players during the 2008 through 2014 seasons. Data were accessed through online search engines, online baseball media guides, and school websites. Results: A total of 5315 player-years and 2575 pitcher-years were identified. Fifty-eight UCL-R cases were found in collegiate pitchers, 40 of which occurred in the Southeastern Conference (SEC) and 18 in the Big Ten. More injuries (36/58) occurred in pitchers who participated in high school baseball in southern states as compared with northern states (22/58), regardless of location of collegiate participation (χ2 = 28.8, P < .05). The injury rate for pitchers who participated in high school baseball in southern states was 25.3 per 1000 player-years versus 19.1 per 1000 player-years in northern states, with a risk ratio of 1.32 (χ2 = 0.89, P = .35). The injury rate for the SEC versus Big Ten pitchers was 13.3 per 1000 player-years versus 7.8 per 1000 player-years, with a risk ratio of 1.71 (χ2 = 1.45, P = .23). Conclusion: There is a greater likelihood of undergoing UCL-R in the SEC compared with the Big Ten. There is also an increased risk for UCL-R for pitchers who played high school baseball in southern states versus northern states, irrespective of collegiate play location. Clinical Relevance

  13. Ulnar Collateral Ligament and Elbow Adaptations in High School Baseball Pitchers

    PubMed Central

    Marshall, Nathan E.; Keller, Robert A.; Van Holsbeeck, Marnix; Moutzouros, Vasilios

    2015-01-01

    Background: Baseball pitchers have adaptive changes in the soft tissues of the throwing elbow. Hypothesis: High school baseball pitchers would show adaptive changes in the ulnar collateral ligament (UCL), such as calcifications and hypoechoic foci, thickening, and increased ulnohumeral joint laxity, on dynamic ultrasound (DUS). Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: Twenty-two asymptomatic high school pitchers, designated as their primary position by their coach, underwent DUS and physical examination of the throwing and nonthrowing elbows prior to the start of the season. UCL substance consistency and thickness, ulnohumeral joint space widening, and soft tissue elbow structures were evaluated. Results: The mean age of the cohort was 16.9 years. Calcifications of the UCL were similar, being present in 7 of 22 (32%) throwing elbows versus 8 of 22 (36%) nonthrowing elbows (P = 0.11). UCL hypoechoic foci also were similar between elbows: 2 of 22 (9%) throwing elbows versus 0 of 22 nonthrowing elbows (P = 0.11). UCL thickness was also found to be similar in both elbows (throwing arm, 6.54 mm vs nonthrowing, 6.71 mm; P = 0.48). Ulnohumeral joint laxity unloaded (throwing arm, 3.13 mm vs nonthrowing, 3.17 mm; P = 0.835) and loaded (throwing arm, 3.87 mm vs nonthrowing arm, 4.11 mm; P = 0.30) was similar between elbows. Throwing elbows showed posteromedial olecranon spurring in 36%, effusions in 27%, and synovitis in 9%. Conclusion: High school pitchers show limited adaptive changes in the elbow, including UCL calcifications, hypoechoic foci, posteromedial olecranon spurring, and effusions. However, these changes are similar to those seen in the nonthrowing elbow, and these younger athletes lack findings seen in professional and collegiate pitchers such as UCL thickening and increased ulnohumeral joint space laxity. Clinical Relevance: Preseason ultrasound examination of the high school pitching elbow lacks the adaptive changes to the

  14. Risk Stratification for Ulnar Collateral Ligament Injury in Major League Baseball Players

    PubMed Central

    DeFroda, Steven F.; Kriz, Peter K.; Hall, Amber M.; Zurakowski, David; Fadale, Paul D.

    2016-01-01

    Background: Ulnar collateral ligament (UCL) injury has become increasingly common in Major League Baseball (MLB) players in recent years. Hypothesis: There is a significant difference in preinjury fastball velocity between MLB pitchers with tears and matched controls without UCL injury. Pitchers with injuries are throwing harder and getting injured earlier in their MLB careers. Study Design: Cohort study; Level of evidence, 3. Methods: From 2007 to 2014, a total of 170 documented UCL injuries (156 pitchers, 14 position players) occurred in MLB. Inclusion criteria for this study consisted of any player who tore his UCL in MLB during this time frame. There were 130 regular-season tears (April-September). From this group, 118 players who pitched more than 100 innings prior to tear were matched to subjects with no tear and were compared using a logistic regression analysis. A subgroup of “early tear” players who threw less than 100 career innings (n = 37) was also identified and compared with the larger tear group using a logistic regression analysis. Results: Of the 130 tears that occurred during the regular season, a significantly larger number (62%) occurred in the first 3 months (P = .011). The rate of UCL tears per MLB player (P = .001) was statistically significant. In the group of 118 matched tears, the mean fastball velocity was greater in the tear group (91.7 mph) compared with the control group (91.0 mph; P = .014). Furthermore, relief pitchers made up a greater percentage of the early tear group (<100 innings) compared with the later tear group (P = .011). Sixteen of the 170 UCL tears (9.4%) were recurrent tears, with 5 of 16 experiencing both tear and retear within the past 4 years. Conclusion: There is a statistically significant difference in the mean fastball velocity of pitchers who injure their UCL. Small increases in pitcher fastball velocity are a main contribution to the increased rate of tear in MLB. In addition, there has been an increased

  15. Rotational Alignment of Femoral Component for Minimal Medial Collateral Ligament Release in Total Knee Arthroplasty

    PubMed Central

    Chon, Je Gyun; Jung, Jae Yong; Kim, Tae In; Jang, Seong Won

    2011-01-01

    Purpose We attempted to determine the degree of rotation of the femoral component to achieve an ideal rectangular flexion gap with minimal medial collateral ligament (MCL) release using a modified measured technique. Materials and Methods Group I consisted of 60 osteoarthritis patients (72 cases) who underwent total knee arthroplasty (TKA) with minimal MCL release and Group II consisted of 48 patients without osteoarthritis (61 cases). We performed computed tomography (CT) scanning of the knee with 90 degree flexion in all of the patients and analyzed the angles between the distal femur landmarks and the tibial mechanical axis using a Picture Archiving Communication system. External rotation of the femoral component from the Whiteside line and posterior condylar line was measured in group I who underwent TKA with minimum MCL release. The variance in the mediolateral flexion gap according to the degree of rotation was also measured using an Auto-Computer Aided Design program. Results The CT scans showed that the Whiteside line, posterior condylar line, and transepicondylar line was more internally rotated on average from the longitudinal axis of tibia by 4.12°, 5.54°, and 4.64°, respectively, in group I compared to group II. In group I, the femoral component was inserted with an average external rotation of 5.6° from the posterior condylar line and with an average external rotation of 2.0° from the Whiteside line with minimal MCL release. From the measurements of the femoral component size and the variance in the degree of rotation using an Auto-CAD program, it was found that the change in the mediolateral flexion gap was greater when the rotation angle was greater and it was greater when the size of femoral component was larger at the same rotation angle. Conclusions The average rotation angle of the femoral component to achieve an ideal rectangular flexion gap with minimal MCL release in TKA was an external rotation of 5.6° from the posterior condylar line

  16. Crack branching in carbon steel. Fracture mechanisms

    NASA Astrophysics Data System (ADS)

    Syromyatnikova, A. S.; Alekseev, A. A.; Levin, A. I.; Lyglaev, A. V.

    2010-04-01

    The fracture surfaces of pressure vessels made of carbon steel that form during crack branching propagation are examined by fractography. Crack branching is found to occur at a crack velocity higher than a certain critical value V > V c . In this case, the material volume that is involved in fracture and depends on the elastoplastic properties of the material and the sample width has no time to dissipate the energy released upon crack motion via the damage mechanisms intrinsic in the material under given deformation conditions (in our case, via cracking according to intragranular cleavage).

  17. Nature of branching in disordered materials

    NASA Astrophysics Data System (ADS)

    Kulkarni, Amit S.

    The phenomenon of structural branching is ubiquitous in a wide array of materials such as polymers, ceramic aggregates, networks and gels. These materials with structural branching are a unique class of disordered materials and often display complex architectures. Branching has a strong influence over the structure-property relationships of these materials. Despite the generic importance across a wide spectrum of materials, our physical understanding of the scientific nature of branching and the analytic description and quantification of branching is at an early stage, though many decades of effort have been made. For polymers, branching is conventionally characterized by hydrodynamic radius (size exclusion chromatography, SEC, rheology) or by counting branch sites (nuclear magnetic resonance spectroscopy, NMR). SEC and rheology are, at best, qualitative; and quantitative characterization techniques like NMR and transmission electron microscopy (TEM) (for ceramic nanoparticulate aggregates) have limitations in providing routine quantification. Effective structure characterization, though an important step in understanding these materials, remains elusive. For ceramic aggregates, theoretical work has dominated and only a few publications on analytic studies exist to support theory. A new generic scaling model is proposed in Chapter I, which encompasses the critical structural features associated with these complex architectures. The central theme of this work is the application of this model to describe a variety of disordered structures like aggregated nano-particulates, long chain branched polymers like polyethylene, hyperbranched polymers, multi-arm star polymers, and cyclic macromolecules. The application of the proposed model to these materials results in a number of fundamental structural parameters, like the mass-fractal dimension, df, the minimum path dimension, dmin, connectivity dimension, c, and the mole fraction branch content, φbr. These dimensions

  18. Bayesian long branch attraction bias and corrections.

    PubMed

    Susko, Edward

    2015-03-01

    Previous work on the star-tree paradox has shown that Bayesian methods suffer from a long branch attraction bias. That work is extended to settings involving more taxa and partially resolved trees. The long branch attraction bias is confirmed to arise more broadly and an additional source of bias is found. A by-product of the analysis is methods that correct for biases toward particular topologies. The corrections can be easily calculated using existing Bayesian software. Posterior support for a set of two or more trees can thus be supplemented with corrected versions to cross-check or replace results. Simulations show the corrections to be highly effective.

  19. Branching model for vegetation. [polarimetric remote sensing

    NASA Technical Reports Server (NTRS)

    Yueh, Simon H.; Kong, J. A.; Jao, Jen K.; Shin, Robert T.; Le Toan, Thuy

    1992-01-01

    In the present branching model for remote sensing of vegetation, the frequency and angular responses of a two-scale cylinder cluster are calculated to illustrate the importance of vegetation architecture. Attention is given to the implementation of a two-scale branching model for soybeans, where the relative location of soybean plants is described by a pair of distribution functions. Theoretical backscattering coefficients evaluated by means of hole-correction pair distribution are in agreement with extensive data collected from soybean fields. The hole-correction approximation is found to be the more realistic.

  20. Needle Assisted Arthroscopic Clysis of the Medial Collateral Ligament of the Knee: a Simple Technique to Improve Exposure in Arthroscopic Knee Surgery

    PubMed Central

    Li, Xinning; Selby, Ronald M.; Newman, Ashley; O’Brien, Stephen J.

    2013-01-01

    During knee arthroscopy, narrowness and tightness maybe encountered in the medial compartment that does not allow sufficient visualization or instrumentation. When this occurs, our team has found it helpful to perform a percutaneous clysis of the deep portion of the medial collateral ligament with a spinal needle. With the knee positioned in 10° to 20° of flexion and a valgus stress is applied. A spinal needle (18 Gauge) is passed percutaneously through the medial collateral ligament between the tibial plateau and undersurface of the medial meniscus. Several passes are made with the spinal needle with the bevel of the needle angled to selectively divide the fibers while keeping the medial collateral ligament under tension. Then with controlled valgus force, the medial compartment will progressively open allowing improved visualization to the posteromedial corner of the knee. This increase in space gives an enhanced visual field and further allows more room for arthroscopic instrumentation. PMID:24416482