Science.gov

Sample records for reduces prolonged frequency-adjusted

  1. Competing for Consciousness: Prolonged Mask Exposure Reduces Object Substitution Masking

    ERIC Educational Resources Information Center

    Goodhew, Stephanie C.; Visser, Troy A. W.; Lipp, Ottmar V.; Dux, Paul E.

    2011-01-01

    In object substitution masking (OSM) a sparse, temporally trailing 4-dot mask impairs target identification, even though it has different contours from, and does not spatially overlap with the target. Here, we demonstrate a previously unknown characteristic of OSM: Observers show reduced masking at prolonged (e.g., 640 ms) relative to intermediate…

  2. Frequency adjustable MEMS vibration energy harvester

    NASA Astrophysics Data System (ADS)

    Podder, P.; Constantinou, P.; Amann, A.; Roy, S.

    2016-10-01

    Ambient mechanical vibrations offer an attractive solution for powering the wireless sensor nodes of the emerging “Internet-of-Things”. However, the wide-ranging variability of the ambient vibration frequencies pose a significant challenge to the efficient transduction of vibration into usable electrical energy. This work reports the development of a MEMS electromagnetic vibration energy harvester where the resonance frequency of the oscillator can be adjusted or tuned to adapt to the ambient vibrational frequency. Micro-fabricated silicon spring and double layer planar micro-coils along with sintered NdFeB micro-magnets are used to construct the electromagnetic transduction mechanism. Furthermore, another NdFeB magnet is adjustably assembled to induce variable magnetic interaction with the transducing magnet, leading to significant change in the spring stiffness and resonance frequency. Finite element analysis and numerical simulations exhibit substantial frequency tuning range (25% of natural resonance frequency) by appropriate adjustment of the repulsive magnetic interaction between the tuning and transducing magnet pair. This demonstrated method of frequency adjustment or tuning have potential applications in other MEMS vibration energy harvesters and micromechanical oscillators.

  3. Some measures to reduce effects of prolonged sleep deprivation.

    PubMed

    Lagarde, D; Batejat, D

    1995-01-01

    Prolonged sleep deprivation is an exceptional situation, encountered in special environments such as sports, civilian and military, and which induces deficits in vigilance and performance. Among the array of measures which may be used to counteract these effects, the authors described a protocol using the combination of small naps, and administration of a pharmacological aid. A detailed description of advantages and drawbacks of each one of these measures is given, illustrated by several examples extracted from different studies. Four aspects of pharmacological aid are reviewed: the effects of amphetamines and amphetamine-like substances, caffeine, eugregoric substances, and the effect of the association small nap + eugregoric substances. The use of these various aids is discussed, and findings show that each one of them finds an application in a specific context.

  4. Standing on a declining surface reduces transient prolonged standing induced low back pain development.

    PubMed

    Gallagher, Kaitlin M; Callaghan, Jack P

    2016-09-01

    While alternating standing position on a sloped surface has proven successful at reducing low back pain during standing, the purpose of this study was to evaluate standing solely on a declining surface to isolate the influence of the postural change. Seventeen participants performed two 75-min prolonged standing occupational simulations- level ground and declining surface. Fifty-three percent of participants (9/17) were categorized as pain developers during the level ground standing condition. For these same pain developers, their average maximum pain scores were 58% lower during sloped standing. All participants showed greater hip flexion, trunk-to-thigh angle flexion, and posterior translation of the trunk center of gravity when standing on the sloped surface. These postural changes could cause the muscles crossing the hip posteriorly to increase passive stiffness and assist with stabilizing the pelvis. This study stresses the importance of hip kinematics, not just lumbar spine posture, in reducing prolonged standing induced low back pain.

  5. Hypoxic ventilatory sensitivity in men is not reduced by prolonged hyperoxia (Predictive Studies V and VI).

    PubMed

    Gelfand, R; Lambertsen, C J; Clark, J M; Hopkin, E

    1998-01-01

    Potential adverse effects on the O2-sensing function of the carotid body when its cells are exposed to toxic O2 pressures were assessed during investigations of human organ tolerance to prolonged continuous and intermittent hyperoxia (Predictive Studies V and VI). Isocapnic hypoxic ventilatory responses (HVR) were determined at 1.0 ATA before and after severe hyperoxic exposures: 1) continuous O2 breathing at 1.5, 2.0, and 2.5 ATA for 17.7, 9.0, and 5.7 h and 2) intermittent O2 breathing at 2.0 ATA (30 min O2-30 min normoxia) for 14.3 O2 h within 30-h total time. Postexposure curvature of HVR hyperbolas was not reduced compared with preexposure controls. The hyperbolas were temporarily elevated to higher ventilations than controls due to increments in respiratory frequency that were proportional to O2 exposure time, not O2 pressure. In humans, prolonged hyperoxia does not attenuate the hypoxia-sensing function of the peripheral chemoreceptors, even after exposures that approach limits of human pulmonary and central nervous system O2 tolerance. Current applications of hyperoxia in hyperbaric O2 therapy and in subsea- and aerospace-related operations are guided by and are well within these exposure limits.

  6. Hypoxic ventilatory sensitivity in men is not reduced by prolonged hyperoxia (Predictive Studies V and VI)

    NASA Technical Reports Server (NTRS)

    Gelfand, R.; Lambertsen, C. J.; Clark, J. M.; Hopkin, E.

    1998-01-01

    Potential adverse effects on the O2-sensing function of the carotid body when its cells are exposed to toxic O2 pressures were assessed during investigations of human organ tolerance to prolonged continuous and intermittent hyperoxia (Predictive Studies V and VI). Isocapnic hypoxic ventilatory responses (HVR) were determined at 1.0 ATA before and after severe hyperoxic exposures: 1) continuous O2 breathing at 1.5, 2.0, and 2.5 ATA for 17.7, 9.0, and 5.7 h and 2) intermittent O2 breathing at 2.0 ATA (30 min O2-30 min normoxia) for 14.3 O2 h within 30-h total time. Postexposure curvature of HVR hyperbolas was not reduced compared with preexposure controls. The hyperbolas were temporarily elevated to higher ventilations than controls due to increments in respiratory frequency that were proportional to O2 exposure time, not O2 pressure. In humans, prolonged hyperoxia does not attenuate the hypoxia-sensing function of the peripheral chemoreceptors, even after exposures that approach limits of human pulmonary and central nervous system O2 tolerance. Current applications of hyperoxia in hyperbaric O2 therapy and in subsea- and aerospace-related operations are guided by and are well within these exposure limits.

  7. Prolonged fermentation of whole wheat sourdough reduces phytate level and increases soluble magnesium.

    PubMed

    Lopez, H W; Krespine, V; Guy, C; Messager, A; Demigne, C; Remesy, C

    2001-05-01

    This work was designed to compare the effects of different leavens (yeast, sourdough, and a mixture of both) on phytic acid (PA) degradation and to assess the repercussions of PA breakdown on phosphorus and magnesium solubility during bread-making. Sourdough fermentation was more efficient than yeast fermentation in reducing the phytate content in whole wheat bread (-62 and -38%, respectively). Furthermore, lactic acid bacteria present in sourdough enhanced acidification, leading to increased magnesium and phosphorus solubility. To intensify phytate breakdown, bran was incubated with microorganisms (yeast or sourdough) before bread-making. Using this new method, the percentage of phytate breakdown was near 90%, whereas 40% of phytate remained in traditional French bread. In conclusion, a prolonged fermentation with sourdough still leads to improved Mg and P solubility by decreasing phytate content and through acidification.

  8. Both acute and prolonged administration of EPO reduce cerebral and systemic vascular conductance in humans.

    PubMed

    Rasmussen, Peter; Kim, Yu-Sok; Krogh-Madsen, Rikke; Lundby, Carsten; Olsen, Niels V; Secher, Niels H; van Lieshout, Johannes J

    2012-03-01

    Administration of erythropoietin (EPO) has been linked to cerebrovascular events. EPO reduces vascular conductance, possibly because of the increase in hematocrit. Whether EPO in itself affects the vasculature remains unknown; here it was evaluated in healthy males by determining systemic and cerebrovascular variables following acute (30,000 IU/d for 3 d; n=8) and chronic (5000 IU/week for 13 wk; n=8) administration of EPO, while the responsiveness of the vasculature was challenged during cycling exercise, with and without hypoxia. Prolonged administration of EPO increased hematocrit from 42.5 ± 3.7 to 47.6 ± 4.1% (P<0.01), whereas hematocrit was unaffected following acute EPO administration. Yet, the two EPO regimes increased arterial pressure similarly (by 8±4 and 7±3 mmHg, respectively; P=0.01) through reduced vascular conductance (by 7±3 and 5±2%; P<0.05). Also, both EPO regimes widened the arterial-to-jugular O(2) differences at rest as well as during normoxic and hypoxic exercise (P<0.01), which indicated reduced cerebral blood flow despite preserved dynamic cerebral autoregulation, and an increase in middle cerebral artery mean blood flow velocity (P<0.05), therefore, reflected vasoconstriction. Thus, administration of EPO to healthy humans lowers systemic and cerebral conductance independent of its effect on hematocrit.

  9. Hydrazinonicotinamide prolongs quantum dot circulation and reduces reticuloendothelial system clearance by suppressing opsonization and phagocyte engulfment

    NASA Astrophysics Data System (ADS)

    Jung, Kyung-Ho; Park, Jin Won; Paik, Jin-Young; Lee, Eun Jeong; Choe, Yearn Seong; Lee, Kyung-Han

    2012-12-01

    In this study, we investigated the effects of hydrazinonicotinamide (HYNIC)—a bifunctional crosslinker widely used to 99mTc radiolabel protein and nanoparticles for imaging studies—on quantum dot opsonization, macrophage engulfment and in vivo kinetics. In streptavidin-coated quantum dots (SA-QDots), conjugation with HYNIC increased the net negative charge without affecting the zeta potential. Confocal microscopy and fluorescence-activated cell sorting showed HYNIC attachment to suppress SA-QDot engulfment by macrophages. Furthermore, HYNIC conjugation suppressed surface opsonization by serum protein including IgG. When intravenously injected into mice, HYNIC conjugation significantly prolonged the circulation of SA-QDots and reduced their hepatosplenic uptake. Diminished reticuloendothelial system clearance of SA-QDots and aminoPEG-QDots by HYNIC conjugation was also demonstrated by in vivo and ex vivo optical imaging. The effects of HYNIC on the opsonization, phagocytosis and in vivo kinetics of quantum dots were reversed by removal of the hydrazine component from HYNIC. Thus, surface functionalization with HYNIC can improve the in vivo kinetics of quantum dots by reducing phagocytosis via suppression of surface opsonization.

  10. Muscle blood flow is reduced with dehydration during prolonged exercise in humans

    PubMed Central

    González-Alonso, José; Calbet, José A L; Nielsen, Bodil

    1998-01-01

    The present study examined whether the blood flow to exercising muscles becomes reduced when cardiac output and systemic vascular conductance decline with dehydration during prolonged exercise in the heat. A secondary aim was to determine whether the upward drift in oxygen consumption (V̇O2) during prolonged exercise is confined to the active muscles.Seven euhydrated, endurance-trained cyclists performed two bicycle exercise trials in the heat (35 °C; 40–50% relative humidity; 61 ± 2% of maximal V̇O2), separated by 1 week. During the first trial (dehydration trial, DE), they bicycled until volitional exhaustion (135 ± 4 min, mean ± s.e.m.), while developing progressive dehydration and hyperthermia (3.9 ± 0.3% body weight loss; 39.7 ± 0.2 °C oesophageal temperature, Toes). In the second trial (control trial), they bicycled for the same period of time while maintaining euhydration by ingesting fluids and stabilizing Toes at 38.2 ± 0.1 °C after 30 min exercise.In both trials, cardiac output, leg blood flow (LBF), vascular conductance and V̇O2 were similar after 20 min exercise. During the 20 min-exhaustion period of DE, cardiac output, LBF and systemic vascular conductance declined significantly (8–14%; P < 0.05) yet muscle vascular conductance was unaltered. In contrast, during the same period of control, all these cardiovascular variables tended to increase. After 135 ± 4 min of DE, the 2.0 ± 0.6 l min−1 lower blood flow to the exercising legs accounted for approximately two-thirds of the reduction in cardiac output. Blood flow to the skin also declined markedly as forearm blood flow was 39 ± 8% (P < 0.05) lower in DE vs. control after 135 ± 4 min.In both trials, whole body V̇O2 and leg V̇O2 increased in parallel and were similar throughout exercise. The reduced leg blood flow in DE was accompanied by an even greater increase in femoral arterial-venous O2 (a-vO2) difference.It is concluded that blood flow to the exercising muscles declines

  11. Preoperative pregabalin prolongs duration of spinal anesthesia and reduces early postoperative pain

    PubMed Central

    Park, MiHye; Jeon, Younghoon

    2016-01-01

    Abstract Background: The administration of oral pregabalin preoperatively has been reported to reduce acute postoperative pain. However, no clinical study to date has yet fully investigated whether or not pregabalin premedication affects sensory and motor blocks using spinal anesthesia and its effect upon early postoperative pain management. This prospective, randomized, and double-blind clinical study was designed to evaluate the efficacy of a single dose of pregabalin in terms of spinal blockade duration and its potential opioid-sparing effect during the first 24 hours subsequent to urogenital surgery. Methods: Forty-four patients scheduled for urogenital surgery under spinal anesthesia were randomly allocated to 2 groups: group C (no premedication; orally administered placebo 2 hours before surgery) and group P (orally administered 150 mg pregabalin 2 hours before surgery). Results: The duration of sensory and motor blockade was significantly prolonged in group P patients when compared with that in group C patients, and the pain scores at postoperative 6 and 24 hours were significantly lower in group P patients. Requests for analgesics during the first postoperative 24 hours were lower among group P patients. Conclusion: Premedication with a single dose of 150 mg pregabalin before surgery promoted the efficacy of intrathecal bupivacaine and improved postoperative analgesia in patients undergoing urogenital surgery under spinal anesthesia. PMID:27603398

  12. The effects of prolonged weightlessness and reduced gravity environments on human survival.

    PubMed

    Taylor, R L

    1993-03-01

    The manned exploration of the solar system and the surfaces of some of the smaller planets and larger satellites requires that we are able to keep the adverse human physiological response to long term exposure to near zero and greatly reduced gravity environments within acceptable limits consistent with metabolic function. This paper examines the physiological changes associated with microgravity conditions with particular reference to the weightless demineralizatoin of bone (WDB). It is suggested that many of these changes are the result of physical/mechanical processes and are not primarily a medical problem. There are thus two immediately obvious and workable, if relatively costly, solutions to the problem of weightlessness. The provision of a near 1 g field during prolonged space flights, and/or the development of rapid transit spacecraft capable of significant acceleration and short flight times. Although these developments could remove or greatly ameliorate the effects of weightlessness during long-distance space flights there remains a problem relating to the long term colonization of the surfaces of Mars, the Moon, and other small solar system bodies. It is not yet known whether or not there is a critical threshold value of 'g' below which viable human physiological function cannot be sustained. If such a threshold exists permanent colonization may only be possible if the threshold value of 'g' is less than that at the surface of the planet on which we wish to settle.

  13. Bile Acids Reduce Prion Conversion, Reduce Neuronal Loss, and Prolong Male Survival in Models of Prion Disease

    PubMed Central

    Cortez, Leonardo M.; Campeau, Jody; Norman, Grant; Kalayil, Marian; Van der Merwe, Jacques; McKenzie, Debbie

    2015-01-01

    ABSTRACT Prion diseases are fatal neurodegenerative disorders associated with the conversion of cellular prion protein (PrPC) into its aberrant infectious form (PrPSc). There is no treatment available for these diseases. The bile acids tauroursodeoxycholic acid (TUDCA) and ursodeoxycholic acid (UDCA) have been recently shown to be neuroprotective in other protein misfolding disease models, including Parkinson's, Huntington's and Alzheimer's diseases, and also in humans with amyotrophic lateral sclerosis. Here, we studied the therapeutic efficacy of these compounds in prion disease. We demonstrated that TUDCA and UDCA substantially reduced PrP conversion in cell-free aggregation assays, as well as in chronically and acutely infected cell cultures. This effect was mediated through reduction of PrPSc seeding ability, rather than an effect on PrPC. We also demonstrated the ability of TUDCA and UDCA to reduce neuronal loss in prion-infected cerebellar slice cultures. UDCA treatment reduced astrocytosis and prolonged survival in RML prion-infected mice. Interestingly, these effects were limited to the males, implying a gender-specific difference in drug metabolism. Beyond effects on PrPSc, we found that levels of phosphorylated eIF2α were increased at early time points, with correlated reductions in postsynaptic density protein 95. As demonstrated for other neurodegenerative diseases, we now show that TUDCA and UDCA may have a therapeutic role in prion diseases, with effects on both prion conversion and neuroprotection. Our findings, together with the fact that these natural compounds are orally bioavailable, permeable to the blood-brain barrier, and U.S. Food and Drug Administration-approved for use in humans, make these compounds promising alternatives for the treatment of prion diseases. IMPORTANCE Prion diseases are fatal neurodegenerative diseases that are transmissible to humans and other mammals. There are no disease-modifying therapies available, despite decades

  14. Reduced Lung Function in a Chronic Asthma Model Is Associated with Prolonged Inflammation, but Independent of Peribronchial Fibrosis

    PubMed Central

    Koerner-Rettberg, Cordula; Doths, Sandra; Stroet, Anke; Schwarze, Jürgen

    2008-01-01

    Background In asthma, mechanisms contributing to chronicity remain to be determined. Recent models of sensitisation with prolonged airway allergen challenges reproduce typical features of chronic asthma. However, the interplay between inflammation, structural changes and lung function is poorly understood. This study was performed to delineate functional, structural and immunological airway changes after cessation of long term challenges to elucidate factors contributing to the development of prolonged lung function changes. Methodology/Principal Findings Mice sensitised systemically were consecutively challenged intranasally with ovalbumin for two or eight weeks. After the end of challenges, lung function, airway inflammation, features of airway remodelling, local T-cell cytokines and systemic ovalbumin-specific antibodies were monitored. Long term challenges resulted in airway hyperresponsiveness lasting 2 weeks and reduced baseline lung function for 6 weeks after their cessation. In contrast, these changes resolved within one week after short term challenges. Prolonged transforming growth factor beta (TGF-β)1 production and marked peribronchial fibrosis were only induced by long term challenges. Importantly, fibrosis became apparent only after the onset of lung function changes and outlasted them. Further, long term challenges led to prolonged and intense airway inflammation with marked lymphocytosis, but moderate eosinophilia, sustained IL-5 production and ovalbumin-specific IgG2a antibodies, the latter suggesting a Th1 component to the immune response. In contrast, following short term challenges airway inflammation was dominated by eosinophils and associated with a strong, but transient IL-13 response. Conclusions Prolonged lung function changes after long term allergen challenges seem to develop and resolve independently of the persistent peribronchial fibrosis. They are more closely associated with intense airway inflammation, marked lymphocytosis

  15. Clinical pharmacists' opportunities to reduce inappropriate prescription of QT-prolonging medications: calls to action.

    PubMed

    Dhanani, Trusha C; Mantovani, Emily H; Turner, J Rick

    2017-04-01

    All biologically active agents carry the potential to lead to adverse reactions in certain individuals, including serious cardiac adverse reactions. Since 2005, there has been an international regulatory landscape governing the investigation of a new drug's propensity to lead to the polymorphic ventricular tachycardia Torsades de Pointes (Torsades), a rare but potentially fatal occurrence. When a regulatory agency considers it appropriate, warning information is placed in a medicine's patient information leaflet (label) concerning drug-induced QT interval prolongation, a phenomenon associated with Torsades. In busy hospital settings, however, prescribers, including cardiologists, make injudicious prescribing decisions that put patients at risk. The science of cardiac safety, including the clinical trials that generate the information about QT prolongation in patient information leaflets, is frequently not part of the curriculum at Schools of Pharmacy. Given that medication-induced cardiotoxicity is extremely serious, we advocate that schools integrate the science of cardiac safety into existing therapeutics/therapeutic medication monitoring courses. Given their expert knowledge of pharmacology, pharmacists working as part of a hospital's clinical team would then be even better placed to review prescribing decisions concerning medications that prolong the QT interval, and alert prescribers in cases where reassessing their decisions seems prudent. National pharmacy societies or other pertinent professional societies could create practice guidelines to support graduates once employed as clinical pharmacists. Clinical pharmacists are well placed to be influential arbiters of safer prescribing decisions. Cardiac safety education during their pharmacy training and practice guideline support from professional societies during their careers can optimize this role.

  16. Delayed adrenal insufficiency long after unilateral adrenalectomy: prolonged glucocorticoid therapy reduced reserved secretory capacity of cortisol.

    PubMed

    Kazama, Itsuro; Komatsu, Yasuhiro; Ohiwa, Takafumi; Sanayama, Kyo; Nagata, Mikio

    2005-06-01

    A 51-year-old woman with Cushing's syndrome underwent unilateral adrenalectomy for left adrenal adenoma. After 7 years of prednisolone treatment (with some interruptions), followed by 4 years of total withdrawal from prednisolone treatment, she presented with hypotension, weight loss, general fatigue, nausea, hyponatremia and hypoglycemia. These clinical features together with a low response in the rapid adrenocorticotropic hormone test led to the diagnosis of acute adrenal insufficiency. Relatively low serum adrenocorticotropic hormone levels in the face of increased demand for cortisol during adrenal crisis suggested a disordered hypothalamic-pituitary function, indicating secondary adrenal insufficiency. This patient demonstrated the etiology of acute adrenal insufficiency long after unilateral adrenalectomy in association with subsequent glucocorticoid therapy. A reduction in the reserved secretory capacity of cortisol after prolonged prednisolone treatment was considered to have induced secondary adrenal insufficiency, even after 4 years of total withdrawal from prednisolone.

  17. Prolonged fasting and cortisol reduce myostatin mRNA levels in tilapia larvae; short-term fasting elevates.

    PubMed

    Rodgers, Buel D; Weber, Gregory M; Kelley, Kevin M; Levine, Michael A

    2003-05-01

    Myostatin negatively regulates muscle growth and development and has recently been characterized in several fishes. We measured fasting myostatin mRNA levels in adult tilapia skeletal muscle and in whole larvae. Although fasting reduced some growth indexes in adults, skeletal muscle myostatin mRNA levels were unaffected. By contrast, larval myostatin mRNA levels were sometimes elevated after a short-term fast and were consistently reduced with prolonged fasting. These effects were specific for myostatin, as mRNA levels of glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphatase were unchanged. Cortisol levels were elevated in fasted larvae with reduced myostatin mRNA, whereas in addition immersion of larvae in 1 ppm (2.8 microM) cortisol reduced myostatin mRNA in a time-dependent fashion. These results suggest that larval myostatin mRNA levels may initially rise but ultimately fall during a prolonged fast. The reduction is likely mediated by fasting-induced hypercortisolemia, indicating divergent evolutionary mechanisms of glucocorticoid regulation of myostatin mRNA, since these steroids upregulate myostatin gene expression in mammals.

  18. Reduced transpiration response to precipitation pulses precedes mortality in a piñon-juniper woodland subject to prolonged drought.

    PubMed

    Plaut, Jennifer A; Wadsworth, W Duncan; Pangle, Robert; Yepez, Enrico A; McDowell, Nate G; Pockman, William T

    2013-10-01

    Global climate change is predicted to alter the intensity and duration of droughts, but the effects of changing precipitation patterns on vegetation mortality are difficult to predict. Our objective was to determine whether prolonged drought or above-average precipitation altered the capacity to respond to the individual precipitation pulses that drive productivity and survival. We analyzed 5 yr of data from a rainfall manipulation experiment in piñon-juniper (Pinus edulis-Juniperus monosperma) woodland using mixed effects models of transpiration response to event size, antecedent soil moisture, and post-event vapor pressure deficit. Replicated treatments included irrigation, drought, ambient control and infrastructure control. Mortality was highest under drought, and the reduced post-pulse transpiration in the droughted trees that died was attributable to treatment effects beyond drier antecedent conditions and reduced event size. In particular, trees that died were nearly unresponsive to antecedent shallow soil moisture, suggesting reduced shallow absorbing root area. Irrigated trees showed an enhanced response to precipitation pulses. Prolonged drought initiates a downward spiral whereby trees are increasingly unable to utilize pulsed soil moisture. Thus, the additive effects of future, more frequent droughts may increase drought-related mortality.

  19. Prolonged head-down tilt exposure reduces maximal cutaneous vasodilator and sweating capacity in humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Shibasaki, M.; Wilson, T. E.; Cui, J.; Levine, B. D.

    2003-01-01

    Cutaneous vasodilation and sweat rate are reduced during a thermal challenge after simulated and actual microgravity exposure. The effects of microgravity exposure on cutaneous vasodilator capacity and on sweat gland function are unknown. The purpose of this study was to test the hypothesis that simulated microgravity exposure, using the 6 degrees head-down tilt (HDT) bed rest model, reduces maximal forearm cutaneous vascular conductance (FVC) and sweat gland function and that exercise during HDT preserves these responses. To test these hypotheses, 20 subjects were exposed to 14 days of strict HDT bed rest. Twelve of those subjects exercised (supine cycle ergometry) at 75% of pre-bed rest heart rate maximum for 90 min/day throughout HDT bed rest. Before and after HDT bed rest, maximal FVC was measured, via plethysmography, by heating the entire forearm to 42 degrees C for 45 min. Sweat gland function was assessed by administering 1 x 10(-6) to 2 M acetylcholine (9 doses) via intradermal microdialysis while simultaneously monitoring sweat rate over the microdialysis membranes. In the nonexercise group, maximal FVC and maximal stimulated sweat rate were significantly reduced after HDT bed rest. In contrast, these responses were unchanged in the exercise group. These data suggest that 14 days of simulated microgravity exposure, using the HDT bed rest model, reduces cutaneous vasodilator and sweating capacity, whereas aerobic exercise training during HDT bed rest preserves these responses.

  20. Extracellular protons reduce quantal content and prolong synaptic currents at the Drosophila larval neuromuscular junction.

    PubMed

    Sandstrom, David J

    2011-10-01

    Fluctuations in extracellular pH occur in the nervous system in response to a number of physiological and pathological processes, such as ischemia, hypercapnea, and high-frequency activity. Using the Drosophila larval neuromuscular junction, the author has examined acute effects of low and high pH on excitability and synaptic transmission. Acidification rapidly and reversibly reduces the size of electrically evoked excitatory junctional currents (EJCs) in a concentration-dependent manner, with transmission nearly abolished at pH 5.0. Conversely, raising pH to 7.8 increases EJC amplitude significantly. Further elevation to pH 8.5 causes an initial increase in amplitude, followed by profound, long-lasting depression of the synapse. Amplitudes of spontaneous miniature EJCs (mEJCs) are modestly, but significantly reduced at pH 5.0. It is therefore the number of quanta released per action potential, rather than the size of individual quanta, that is most strongly affected. Decay times of both EJCs and mEJCs are dramatically lengthened at low pH, suggesting that glutamate remains in the synaptic cleft for much longer than normal. Presynaptic excitability is also reduced, as indicated by increased latency between nerve shock and EJC onset. The response to low pH was not altered by mutations in genes encoding Transient Receptor Potential, Mucolipin subfamily (TRPML) and Slowpoke ion channels, which had previously been implicated as possible targets of extracellular protons. The author concludes that extracellular protons have strong effects on the release of glutamate and the time course of synaptic currents. These phenotypes can be exploited to study the mechanisms of acid-mediated changes in neuronal function, and to pursue the way in which pH modulates synaptic function in normal and pathophysiological conditions.

  1. Poly(DL:lactic acid-castor oil) 3:7-bupivacaine formulation: reducing burst effect prolongs efficacy in vivo.

    PubMed

    Sokolsky-Papkov, Marina; Golovanevski, Ludmila; Domb, Abraham J; Weiniger, Carolyn F

    2010-06-01

    Prolonged analgesia may be achieved using a single injection of slow-release local anesthetic formulation. The study objective was to improve the efficacy of a previously reported formulation comprising 10% bupivacaine in poly(DL:lactic acid co castor oil) 3:7. The polymer was loaded with 15% bupivacaine and injected through a 22G needle close to the sciatic nerve of ICR mice. Sensory and motor nerve blockade were measured. The efficacy and toxicity of the polymer-drug combination were determined. Sixty percent of the incorporated bupivacaine was released during 1 week in vitro. During in vitro release no burst effect was seen, suggesting low toxicity of the formulation. Single injection of 0.1 mL of 15% polymer-bupivacaine formulation caused motor block that lasted 64 h and sensory block that lasted 96 h. The MTD of the polymer-drug formulation was established as 0.175 mL. Microscopic examination of the injection sites revealed reversible nerve inflammation and normal internal organs. The polymer poly(DL:lactic acid co castor oil) 3:7 is a safe carrier for prolonged activity of bupivacaine up to 96 h. The increase of drug load in the formulation reduces the drug release rates due to stronger polymer-drug interactions and higher overall hydrophobicity of the formulation.

  2. Prolonged preoperative fasting in elective surgical patients: why should we reduce it?

    PubMed

    Pimenta, Gunther Peres; de Aguilar-Nascimento, José Eduardo

    2014-02-01

    Despite the abundance of evidence to the contrary, 6-8 hours of total preoperative fasting is still considered essential by many surgeons and anesthesiologists, based on the strength of old concepts. Patients frequently end up fasting for 12 hours or more because of delays and changes in operating room schedules. The metabolic response to long fasting leads to intensification of the organic response occurring after trauma, which is mainly manifested as increased insulin resistance, an acute-phase response, and loss of lean body mass. In fact, there has not been any evidence indicating that a shorter fast of 2-3 hours, which includes oral clear or carbohydrate (CHO)-rich (12.5% carbohydrates, 50 kcal/100 mL) fluids, results in an increased risk of aspiration, regurgitation, or related morbidity compared with the standard policy of "nil by mouth after midnight." In addition, preoperative treatment with CHO-rich fluids may reduce postoperative discomfort and, for patients undergoing major abdominal surgery, may decrease the duration of postoperative hospitalization. New formulas for preoperative oral fluids containing amino acid or protein such as glutamine or whey protein are also potential candidates for early preoperative treatment and merit further study.

  3. Prolonged High Fat Diet Reduces Dopamine Reuptake without Altering DAT Gene Expression

    PubMed Central

    Cone, Jackson J.; Chartoff, Elena H.; Potter, David N.; Ebner, Stephanie R.; Roitman, Mitchell F.

    2013-01-01

    The development of diet-induced obesity (DIO) can potently alter multiple aspects of dopamine signaling, including dopamine transporter (DAT) expression and dopamine reuptake. However, the time-course of diet-induced changes in DAT expression and function and whether such changes are dependent upon the development of DIO remains unresolved. Here, we fed rats a high (HFD) or low (LFD) fat diet for 2 or 6 weeks. Following diet exposure, rats were anesthetized with urethane and striatal DAT function was assessed by electrically stimulating the dopamine cell bodies in the ventral tegmental area (VTA) and recording resultant changes in dopamine concentration in the ventral striatum using fast-scan cyclic voltammetry. We also quantified the effect of HFD on membrane associated DAT in striatal cell fractions from a separate group of rats following exposure to the same diet protocol. Notably, none of our treatment groups differed in body weight. We found a deficit in the rate of dopamine reuptake in HFD rats relative to LFD rats after 6 but not 2 weeks of diet exposure. Additionally, the increase in evoked dopamine following a pharmacological challenge of cocaine was significantly attenuated in HFD relative to LFD rats. Western blot analysis revealed that there was no effect of diet on total DAT protein. However, 6 weeks of HFD exposure significantly reduced the 50 kDa DAT isoform in a synaptosomal membrane-associated fraction, but not in a fraction associated with recycling endosomes. Our data provide further evidence for diet-induced alterations in dopamine reuptake independent of changes in DAT production and demonstrates that such changes can manifest without the development of DIO. PMID:23516454

  4. Frequency adjustment and synchrony in networks of delayed pulse-coupled oscillators

    NASA Astrophysics Data System (ADS)

    Nishimura, Joel

    2015-01-01

    We introduce a system of pulse-coupled oscillators that can change both their phases and frequencies and prove that when there is a separation of time scales between phase and frequency adjustment the system converges to exact synchrony on strongly connected graphs with time delays. The analysis involves decomposing the network into a forest of tree-like structures that capture causality. These results provide a robust method of sensor net synchronization as well as demonstrate a new avenue of possible pulse-coupled oscillator research.

  5. CCK-58 prolongs the intermeal interval, whereas CCK-8 reduces this interval: not all forms of cholecystokinin have equal bioactivity.

    PubMed

    Sayegh, Ayman I; Washington, Martha C; Raboin, Shannon J; Aglan, Amnah H; Reeve, Joseph R

    2014-05-01

    It has been accepted for decades that "all forms of cholecystokinin (CCK) have equal bioactivity," despite accumulating evidence to the contrary. To challenge this concept, we compared two feeding responses, meal size (MS, 10% sucrose) and intermeal interval (IMI), in response to CCK-58, which is the major endocrine form of CCK, and CCK-8, which is the most abundantly utilized form. Doses (0, 0.1, 0.5, 0.75, 1, 3 and 5 nmol/kg) were administered intraperitoneally over a 210-min test to Sprague Dawley rats that had been food-deprived overnight. We found that (1) all doses of CCK-58, except the lowest dose, and all doses of CCK-8, except the lowest two doses, reduced food intake more than vehicle did; (2) at two doses, 0.75 and 3 nmol/kg, CCK-58 increased the IMI, while CCK-8 failed to alter this feeding response; and (3) CCK-58, at all but the lowest two doses, increased the satiety ratio (IMI between first and second meals (min) divided by first MS (ml)) relative to vehicle, while CCK-8 did not affect this value. These findings demonstrate that the only circulating form of CCK in rats, CCK-58, prolongs the IMI more than CCK-8, the peptide generally utilized in feeding studies. Taken together, these results add to a growing list of functions where CCK-8 and CCK-58 express qualitatively different bioactivities. In conclusion, the hypothesis that "all forms of cholecystokinin (CCK) have equal bioactivity" is not supported.

  6. Prolonged treatment with pramipexole promotes physical interaction of striatal dopamine D3 autoreceptors with dopamine transporters to reduce dopamine uptake.

    PubMed

    Castro-Hernández, Javier; Afonso-Oramas, Domingo; Cruz-Muros, Ignacio; Salas-Hernández, Josmar; Barroso-Chinea, Pedro; Moratalla, Rosario; Millan, Mark J; González-Hernández, Tomás

    2015-02-01

    The dopamine (DA) transporter (DAT), a membrane glycoprotein expressed in dopaminergic neurons, clears DA from extracellular space and is regulated by diverse presynaptic proteins like protein kinases, α-synuclein, D2 and D3 autoreceptors. DAT dysfunction is implicated in Parkinson's disease and depression, which are therapeutically treated by dopaminergic D2/D3 receptor (D2/D3R) agonists. It is, then, important to improve our understanding of interactions between D3R and DAT. We show that prolonged administration of pramipexole (0.1mg/kg/day, 6 to 21 days), a preferential D3R agonist, leads to a decrease in DA uptake in mouse striatum that reflects a reduction in DAT affinity for DA in the absence of any change in DAT density or subcellular distribution. The effect of pramipexole was absent in mice with genetically-deleted D3R (D3R(-/-)), yet unaffected in mice genetically deprived of D2R (D2R(-/-)). Pramipexole treatment induced a physical interaction between D3R and DAT, as assessed by co-immunoprecipitation and in situ proximity ligation assay. Furthermore, it promoted the formation of DAT dimers and DAT association with both D2R and α-synuclein, effects that were abolished in D3R(-/-) mice, yet unaffected in D2R(-/-) mice, indicating dependence upon D3R. Collectively, these data suggest that prolonged treatment with dopaminergic D3 agonists provokes a reduction in DA reuptake by dopaminergic neurons related to a hitherto-unsuspected modification of the DAT interactome. These observations provide novel insights into the long-term antiparkinson, antidepressant and additional clinical actions of pramipexole and other D3R agonists.

  7. Aldosterone-to-Renin Ratio Is Associated With Reduced 24-Hour Heart Rate Variability and QTc Prolongation in Hypertensive Patients.

    PubMed

    Grübler, Martin R; Kienreich, Katharina; Gaksch, Martin; Verheyen, Nicolas; Hartaigh, Bríain Ó; Fahrleitner-Pammer, Astrid; März, Winfried; Schmid, Johannes; Oberreither, Eva-Maria; Wetzel, Julia; Catena, Cristiana; Sechi, Leonardo A; Pieske, Burkert; Tomaschitz, Andreas; Pilz, Stefan

    2016-02-01

    Aldosterone is considered to exert direct effects on the myocardium and the sympathetic nervous system. Both QT time and heart rate (HR) variability (HRV) are considered to be markers of arrhythmic risk and autonomous dysregulation. In this study, we investigated the associations between aldosterone, QT time, and HRV in patients with arterial hypertension.We recruited 477 hypertensive patients (age: 60.2 ± 10.2 years; 52.3% females) with a mean systolic/diastolic 24-hour ambulatory blood pressure monitoring (ABPM) value of 128 ± 12.8/77.1 ± 9.2 mmHg and with a median of 2 (IQR: 1-3) antihypertensive agents. Patients were recruited from the outpatient clinic at the Department of Internal Medicine of the Medical University of Graz, Austria. Blood samples, 24-hour HRV derived from 24-hour blood pressure monitoring (ABPM) and ECG's were obtained. Plasma aldosterone and plasma renin concentrations were measured by means of a radioimmunoassay. Twenty-four-hour urine specimens were collected in parallel with ABPM.Mean QTc was 423.3 ± 42.0 milliseconds for males and 434.7 ± 38.3 milliseconds for females. Mean 24H-HR and 24H-HRV was 71.9 ± 9.8 and 10.0 ± 3.6 bpm, respectively. In linear regression analyses adjusted for age, sex, body mass index, ABPM, and current medication, aldosterone to active renin ratio (AARR) was significantly associated with the QTc interval, a marker for cardiac repolarization abnormalities (mean = 426 ± 42.4 milliseconds; β-coefficient = 0.121; P = 0.03) as well as with the 24-hour heart rate variability a surrogate for autonomic dysfunction (median = 9.67 [IQR = 7.38-12.22 bpm]; β-coefficient = -0.133; P = 0.01).In hypertensive patients, AARR is significantly related to QTc prolongation as well as HRV. Further studies investigating the effects of mineralocorticoid receptor blocker and aldosterone synthase inhibitors on QTc and HRV are warranted.

  8. Dietary Supplementation with the Microalga Galdieria sulphuraria (Rhodophyta) Reduces Prolonged Exercise-Induced Oxidative Stress in Rat Tissues

    PubMed Central

    Carfagna, Simona; Napolitano, Gaetana; Barone, Daniela; Pinto, Gabriele; Venditti, Paola

    2015-01-01

    We studied the effects of ten-day 1% Galdieria sulphuraria dietary supplementation on oxidative damage and metabolic changes elicited by acute exercise (6-hour swimming) determining oxygen consumption, lipid hydroperoxides, protein bound carbonyls in rat tissue (liver, heart, and muscle) homogenates and mitochondria, tissue glutathione peroxidase and glutathione reductase activities, glutathione content, and rates of H2O2 mitochondrial release. Exercise increased oxidative damage in tissues and mitochondria and decreased tissue content of reduced glutathione. Moreover, it increased State 4 and decreased State 3 respiration in tissues and mitochondria. G. sulphuraria supplementation reduced the above exercise-induced variations. Conversely, alga supplementation was not able to modify the exercise-induced increase in mitochondrial release rate of hydrogen peroxide and in liver and heart antioxidant enzyme activities. The alga capacity to reduce lipid oxidative damage without reducing mitochondrial H2O2 release can be due to its high content of C-phycocyanin and glutathione, which are able to scavenge peroxyl radicals and contribute to phospholipid hydroperoxide metabolism, respectively. In conclusion, G. sulphuraria ability to reduce exercise-linked oxidative damage and mitochondrial dysfunction makes it potentially useful even in other conditions leading to oxidative stress, including hyperthyroidism, chronic inflammation, and ischemia/reperfusion. PMID:25874021

  9. Prolonged C2 spinal hemisection-induced inactivity reduces diaphragm muscle specific force with modest, selective atrophy of type IIx and/or IIb fibers.

    PubMed

    Mantilla, Carlos B; Greising, Sarah M; Zhan, Wen-Zhi; Seven, Yasin B; Sieck, Gary C

    2013-02-01

    The diaphragm muscle (DIAm) is critically responsible for sustaining ventilation. Previously we showed in a commonly used model of spinal cord injury, unilateral spinal cord hemisection at C(2) (SH), that there are minimal changes to muscle fiber cross-sectional area (CSA) and fiber type distribution following 14 days of SH-induced ipsilateral DIAm inactivity. In the present study, effects of long-term SH-induced inactivity on DIAm fiber size and force were examined. We hypothesized that prolonged inactivity would not result in substantial DIAm atrophy or force loss. Adult rats were randomized to control or SH groups (n = 34 total). Chronic bilateral DIAm electromyographic (EMG) activity was monitored during resting breathing. Minimal levels of spontaneous recovery of ipsilateral DIAm EMG activity were evident in 42% of SH rats (<25% of preinjury root mean square amplitude). Following 42 days of SH, DIAm specific force was reduced 39%. There was no difference in CSA for type I or IIa DIAm fibers in SH rats compared with age, weight-matched controls (classification based on myosin heavy chain isoform expression). Type IIx and/or IIb DIAm fibers displayed a modest 20% reduction in CSA (P < 0.05). Overall, there were no differences in the distribution of fiber types or the contribution of each fiber type to the total DIAm CSA. These data indicate that reduced specific force following prolonged inactivity of the DIAm is associated with modest, fiber type selective adaptations in muscle fiber size and fiber type distribution.

  10. Prolonged experimental drought reduces plant hydraulic conductance and transpiration and increases mortality in a piñon–juniper woodland

    PubMed Central

    Pangle, Robert E; Limousin, Jean-Marc; Plaut, Jennifer A; Yepez, Enrico A; Hudson, Patrick J; Boutz, Amanda L; Gehres, Nathan; Pockman, William T; McDowell, Nate G

    2015-01-01

    Plant hydraulic conductance (ks) is a critical control on whole-plant water use and carbon uptake and, during drought, influences whether plants survive or die. To assess long-term physiological and hydraulic responses of mature trees to water availability, we manipulated ecosystem-scale water availability from 2007 to 2013 in a piñon pine (Pinus edulis) and juniper (Juniperus monosperma) woodland. We examined the relationship between ks and subsequent mortality using more than 5 years of physiological observations, and the subsequent impact of reduced hydraulic function and mortality on total woody canopy transpiration (EC) and conductance (GC). For both species, we observed significant reductions in plant transpiration (E) and ks under experimentally imposed drought. Conversely, supplemental water additions increased E and ks in both species. Interestingly, both species exhibited similar declines in ks under the imposed drought conditions, despite their differing stomatal responses and mortality patterns during drought. Reduced whole-plant ks also reduced carbon assimilation in both species, as leaf-level stomatal conductance (gs) and net photosynthesis (An) declined strongly with decreasing ks. Finally, we observed that chronically low whole-plant ks was associated with greater canopy dieback and mortality for both piñon and juniper and that subsequent reductions in woody canopy biomass due to mortality had a significant impact on both daily and annual canopy EC and GC. Our data indicate that significant reductions in ks precede drought-related tree mortality events in this system, and the consequence is a significant reduction in canopy gas exchange and carbon fixation. Our results suggest that reductions in productivity and woody plant cover in piñon–juniper woodlands can be expected due to reduced plant hydraulic conductance and increased mortality of both piñon pine and juniper under anticipated future conditions of more frequent and persistent

  11. Myxomavirus-Derived Serpin Prolongs Survival and Reduces Inflammation and Hemorrhage in an Unrelated Lethal Mouse Viral Infection

    PubMed Central

    Chen, Hao; Zheng, Donghang; Abbott, Jeff; Liu, Liying; Bartee, Mee Y.; Long, Maureen; Davids, Jennifer; Williams, Jennifer; Feldmann, Heinz; Strong, James; Grau, Katrina R.; Tibbetts, Scott; Macaulay, Colin; McFadden, Grant; Thoburn, Robert; Lomas, David A.; Spinale, Francis G.; Virgin, Herbert W.

    2013-01-01

    Lethal viral infections produce widespread inflammation with vascular leak, clotting, and bleeding (disseminated intravascular coagulation [DIC]), organ failure, and high mortality. Serine proteases in clot-forming (thrombotic) and clot-dissolving (thrombolytic) cascades are activated by an inflammatory cytokine storm and also can induce systemic inflammation with loss of normal serine protease inhibitor (serpin) regulation. Myxomavirus secretes a potent anti-inflammatory serpin, Serp-1, that inhibits clotting factor X (fX) and thrombolytic tissue- and urokinase-type plasminogen activators (tPA and uPA) with anti-inflammatory activity in multiple animal models. Purified serpin significantly improved survival in a murine gammaherpesvirus 68 (MHV68) infection in gamma interferon receptor (IFN-γR) knockout mice, a model for lethal inflammatory vasculitis. Treatment of MHV68-infected mice with neuroserpin, a mammalian serpin that inhibits only tPA and uPA, was ineffective. Serp-1 reduced virus load, lung hemorrhage, and aortic, lung, and colon inflammation in MHV68-infected mice and also reduced virus load. Neuroserpin suppressed a wide range of immune spleen cell responses after MHV68 infection, while Serp-1 selectively increased CD11c+ splenocytes (macrophage and dendritic cells) and reduced CD11b+ tissue macrophages. Serp-1 altered gene expression for coagulation and inflammatory responses, whereas neuroserpin did not. Serp-1 treatment was assessed in a second viral infection, mouse-adapted Zaire ebolavirus in wild-type BALB/c mice, with improved survival and reduced tissue necrosis. In summary, treatment with this unique myxomavirus-derived serpin suppresses systemic serine protease and innate immune responses caused by unrelated lethal viral infections (both RNA and DNA viruses), providing a potential new therapeutic approach for treatment of lethal viral sepsis. PMID:23774438

  12. Prolonged experimental drought reduces plant hydraulic conductance and transpiration and increases mortality in a piñon-juniper woodland.

    PubMed

    Pangle, Robert E; Limousin, Jean-Marc; Plaut, Jennifer A; Yepez, Enrico A; Hudson, Patrick J; Boutz, Amanda L; Gehres, Nathan; Pockman, William T; McDowell, Nate G

    2015-04-01

    Plant hydraulic conductance (k s) is a critical control on whole-plant water use and carbon uptake and, during drought, influences whether plants survive or die. To assess long-term physiological and hydraulic responses of mature trees to water availability, we manipulated ecosystem-scale water availability from 2007 to 2013 in a piñon pine (Pinus edulis) and juniper (Juniperus monosperma) woodland. We examined the relationship between k s and subsequent mortality using more than 5 years of physiological observations, and the subsequent impact of reduced hydraulic function and mortality on total woody canopy transpiration (E C) and conductance (G C). For both species, we observed significant reductions in plant transpiration (E) and k s under experimentally imposed drought. Conversely, supplemental water additions increased E and k s in both species. Interestingly, both species exhibited similar declines in k s under the imposed drought conditions, despite their differing stomatal responses and mortality patterns during drought. Reduced whole-plant k s also reduced carbon assimilation in both species, as leaf-level stomatal conductance (g s) and net photosynthesis (A n) declined strongly with decreasing k s. Finally, we observed that chronically low whole-plant k s was associated with greater canopy dieback and mortality for both piñon and juniper and that subsequent reductions in woody canopy biomass due to mortality had a significant impact on both daily and annual canopy E C and G C. Our data indicate that significant reductions in k s precede drought-related tree mortality events in this system, and the consequence is a significant reduction in canopy gas exchange and carbon fixation. Our results suggest that reductions in productivity and woody plant cover in piñon-juniper woodlands can be expected due to reduced plant hydraulic conductance and increased mortality of both piñon pine and juniper under anticipated future conditions of more frequent and

  13. Dynamic Succession of Groundwater Sulfate-Reducing Communities during Prolonged Reduction of Uranium in a Contaminated Aquifer.

    PubMed

    Zhang, Ping; He, Zhili; Van Nostrand, Joy D; Qin, Yujia; Deng, Ye; Wu, Liyou; Tu, Qichao; Wang, Jianjun; Schadt, Christopher W; W Fields, Matthew; Hazen, Terry C; Arkin, Adam P; Stahl, David A; Zhou, Jizhong

    2017-03-16

    To further understand the diversity and dynamics of SRB in response to substrate amendment, we sequenced genes coding for the dissimilatory sulfite reductase (dsrA) in groundwater samples collected after an emulsified vegetable oil (EVO) amendment, which sustained U(VI)-reducing conditions for one year in a fast-flowing aquifer. EVO amendment significantly altered the composition of groundwater SRB communities. Sequences having no closely related-described species dominated (80%) the indigenous SRB communities in nonamended wells. After EVO amendment, Desulfococcus, Desulfobacterium, and Desulfovibrio, known for long-chain-fatty-acid, short-chain-fatty-acid and H2 oxidation and U(VI) reduction, became dominant accounting for 7 ± 2%, 21 ± 8%, and 55 ± 8% of the SRB communities, respectively. Succession of these SRB at different bioactivity stages based on redox substrates/products (acetate, SO4(-2), U(VI), NO3(-), Fe(II), and Mn(II)) was observed. Desulfovibrio and Desulfococcus dominated SRB communities at 4-31 days, whereas Desulfobacterium became dominant at 80-140 days. By the end of the experiment (day 269), the abundance of these SRB decreased but the overall diversity of groundwater SRB was still higher than non-EVO controls. Up to 62% of the SRB community changes could be explained by groundwater geochemical variables, including those redox substrates/products. A significant (P < 0.001) correlation was observed between groundwater U(VI) concentrations and Desulfovibrio abundance. Our results showed that the members of SRB and their dynamics were correlated significantly with slow EVO biodegradation, electron donor production and maintenance of U(VI)-reducing conditions in the aquifer.

  14. Conservation of body calcium by increased dietary intake of potassium: A potential measure to reduce the osteoporosis process during prolonged exposure to microgravity

    NASA Technical Reports Server (NTRS)

    Nechay, Bohdan R.

    1989-01-01

    During the 1988 NASA Summer Faculty Fellowship Program, it was proposed that the loss of skeletal calcium upon prolonged exposure to microgravity could be explained, in part, by a renal maladjustment characterized by an increased urinary excretion of calcium. It was theorized that because the conservation of body fluids and electrolytes depends upon the energy of adenosine triphosphate and enzymes that control the use of its energy for renal ion transport, an induction of renal sodium and potassium-dependent adenosine triphosphatase (Na + K ATPase) by oral loading with potassium would increase the reabsorption of sodium directly and that of calcium indirectly, leading to improved hydration and to reduced calcium loss. Preliminary studies showed the following. Rats drinking water containing 0.2 M potassium chloride for six to 13 days excreted in urine 22 muEq of calcium and 135 muEq of sodium per 100 grams of body weight per day. The corresponding values for control rats drinking tap water were 43 muEq and 269 muEq respectively. Renal Na + K ATPase activity in potassium loaded rats was higher than in controls. Thus, oral potassium loading resulted in increased Na + K ATPase activity and diminished urinary excretion of calcium and of sodium as predicted by the hypothesis. An extension of these studies to humans has the potential of resulting in development of harmless, non-invasive, drug-free, convenient measures to reduce bone loss and other electrolyte and fluid problems in space travelers exposed to prolonged periods of microgravity.

  15. A hip abduction exercise prior to prolonged standing increased movement while reducing cocontraction and low back pain perception in those initially reporting low back pain.

    PubMed

    Viggiani, Daniel; Callaghan, Jack P

    2016-12-01

    Persons who develop low back pain from prolonged standing exhibit increased muscle cocontraction, decreased movement and increased spine extension. However, it is unclear how these factors relate to pain development. The purpose of this study was to use hip abductor fatigue to manipulate muscle activity patterns and determine its effects on standing behaviours and pain development. Forty participants stood for two hours twice, once following a hip abductor fatigue exercise (fatigue), and once without exercise beforehand (control). Trunk and gluteal muscle activity were measured to determine cocontraction. Lumbo-pelvic angles and force plates were used to assess posture and movement strategies. Visual analog scales differentiated pain (PDs) and non-pain developers (NPDs). PDs reported less low back pain during the fatigue session, with females having earlier reductions of similar scale than males. The fatigue session reduced gluteal and trunk cocontraction and increased centre of pressure movement; male and female PDs had opposing spine posture compensations. Muscle fatigue prior to standing reduced cocontraction, increased movement during standing and reduced the low back pain developed by PDs; the timing of pain reductions depended on spine postures adopted during standing.

  16. Multifactorial Gene Therapy Enhancing the Glutamate Uptake System and Reducing Oxidative Stress Delays Symptom Onset and Prolongs Survival in the SOD1-G93A ALS Mouse Model.

    PubMed

    Benkler, Chen; Barhum, Yael; Ben-Zur, Tali; Offen, Daniel

    2016-01-01

    The 150-year-long search for treatments of amyotrophic lateral sclerosis (ALS) is still fueled by frustration over the shortcomings of available therapeutics. Contributing to the therapeutic limitations might be the targeting of a single aspect of this multifactorial-multisystemic disease. In an attempt to overcome this, we devised a novel multifactorial-cocktail treatment, using lentiviruses encoding: EAAT2, GDH2, and NRF2, that act synergistically to address the band and width of the effected excito-oxidative axis, reducing extracellular-glutamate and glutamate availability while improving the metabolic state and the anti-oxidant response. This strategy yielded particularly impressive results, as all three genes together but not separately prolonged survival in ALS mice by an average of 19-22 days. This was accompanied by improvement in every parameter evaluated, including body-weight loss, reflex score, neurologic score, and motor performance. We hope to provide a novel strategy to slow down disease progression and alleviate symptoms of patients suffering from ALS.

  17. Daily Oxygen/O₃ Treatment Reduces Muscular Fatigue and Improves Cardiac Performance in Rats Subjected to Prolonged High Intensity Physical Exercise.

    PubMed

    Di Filippo, C; Trotta, M C; Maisto, R; Siniscalco, D; Luongo, M; Mascolo, L; Alfano, R; Accardo, M; Rossi, C; Ferraraccio, F; D'Amico, M

    2015-01-01

    Rats receiving daily intraperitoneal administration of O2 and running on a treadmill covered an average distance of 482.8 ± 21.8 m/week as calculated during 5-week observation. This distance was increased in rats receiving daily intraperitoneal administration of an oxygen/O3 mixture at a dose of 100; 150; and 300 μg/kg with the maximum increase being +34.5% at 300 μg/kg and still present after stopping the administration of oxygen/O3. Oxygen/O3 decreased the mean arterial blood pressure (-13%), the heart rate (-6%), the gastrocnemius and cardiac hypertrophy, and fibrosis and reduced by 49% the left ventricular mass and relative wall thickness measurements. Systolic and diastolic functions were improved in exercised oxygen/O3 rats compared to O2 rats. Oxygen/O3 treatment led to higher MPI index starting from the dose of 150 μg/kg (p < 0.05) and more effective (+14%) at a dose of 300 μg/kg oxygen/O3. Oxygen/O3 dose-dependently increased the expression of the antioxidant enzymes Mn-SOD and GPx1 and of eNOS compared to the exercised O2 rats. The same doses resulted in decrease of LDH levels, CPK, TnI, and nitrotyrosine concentration in the heart and gastrocnemius tissues, arguing a beneficial effect of the ozone molecule against the fatigue induced by a prolonged high intensity exercise.

  18. P2X7 antagonism using Brilliant Blue G reduces body weight loss and prolongs survival in female SOD1G93A amyotrophic lateral sclerosis mice

    PubMed Central

    Bartlett, Rachael; Sluyter, Vanessa; Watson, Debbie

    2017-01-01

    Background Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease characterised by the accumulation of aggregated proteins, microglia activation and motor neuron loss. The mechanisms underlying neurodegeneration and disease progression in ALS are unknown, but the ATP-gated P2X7 receptor channel is implicated in this disease. Therefore, the current study aimed to examine P2X7 in the context of neurodegeneration, and investigate whether the P2X7 antagonist, Brilliant Blue G (BBG), could alter disease progression in a murine model of ALS. Methods Human SOD1G93A transgenic mice, which normally develop ALS, were injected with BBG or saline, three times per week, from pre-onset of clinical disease (62–64 days of age) until end-stage. During the course of treatment mice were assessed for weight, clinical score and survival, and motor coordination, which was assessed by rotarod performance. Various parameters from end-stage mice were assessed as follows. Motor neuron loss and microgliosis were assessed by immunohistochemistry. Relative amounts of lumbar spinal cord SOD1 and P2X7 were quantified by immunoblotting. Serum monocyte chemoattractant protein-1 was measured by ELISA. Splenic leukocyte populations were assessed by flow cytometry. Relative expression of splenic and hepatic P2X7 mRNA was measured by quantitative real-time PCR. Lumbar spinal cord SOD1 and P2X7 were also quantified by immunoblotting in untreated female SOD1G93A mice during the course of disease. Results BBG treatment reduced body weight loss in SOD1G93A mice of combined sex, but had no effect on clinical score, survival or motor coordination. BBG treatment reduced body weight loss in female, but not male, SOD1G93A mice. BBG treatment also prolonged survival in female, but not male, SOD1G93A mice, extending the mean survival time by 4.3% in female mice compared to female mice treated with saline. BBG treatment had no effect on clinical score or motor coordination in

  19. [Application of prolonged flow-aspiration drainage of laparotomy wounds in order to reduce suppurative septic complications in bowels reconstructive surgery].

    PubMed

    Shcherba, S N; Polovinkin, V V

    2014-01-01

    The article presents the follow-up study of 254 onco-proctologic patients after reconstructive abdominoperitoneal resections. Patients were divided into 4 statistically homogeneous groups (2 main and 2 control groups). A comparative analysis of middle and lateral laparotomy wounds healing was made. Laparotomy wounds were stitched up using conventional method (in layers, tightly) and using other method of prolonged flow-aspiration drainage of hypodermic tissue. Postoperative wound infections were noted in 11.4% patients in case of conventional means. The prolonged flow-aspiration drainage in laparotomy wounds causes only 1.5% of complications.

  20. Hyaluronidase inhibitors (sodium cromoglycate and sodium auro-thiomalate) reduce the local tissue damage and prolong the survival time of mice injected with Naja kaouthia and Calloselasma rhodostoma venoms.

    PubMed

    Yingprasertchai, Senee; Bunyasrisawat, Srisurat; Ratanabanangkoon, Kavi

    2003-11-01

    Experiments have been carried out to find potent inhibitors of hyaluronidases of Naja kaouthia (NK) and Calloselasma rhodostoma (CR) venoms with the aim of reducing local tissue damage and systemic toxicities caused by the venoms. Seven drugs/chemicals known to inhibit hyaluronidases were tested for their activity on venom enzymes. These were: sodium cromoglycate (SC), sodium aurothiomalate (SAT), apigenin, kaemferol, phenylbutazone, oxyphenbutazone and fenoprofen. The results showed that SC or SAT at 10 mM, completely inhibited the enzymes of both venoms. In in vivo experiments, SC or SAT, when incubated with NK venom prior to injection, significantly reduced edema and myonecrosis. In the case of CR venom, hemorrhage, in addition to edema and myonecrosis, was also significantly reduced. In the independent type experiment, SC or SAT were effective if injected within 1 min after the injection of venom. At longer time intervals of 3 and 10 min the inhibitors were effective in reducing some parameters of local tissue necrosis but the extent of inhibition was lower. SC and SAT at 256 and 195 microg/mouse, respectively, significantly prolonged the survival time of mice receiving lethal doses of NK. In the case of CR venoms, the two inhibitors not only prolonged the survival time but also prevented death of mice receiving lethal doses of the venom. The other inhibitors were poorly soluble in water and were studied only on enzyme inhibition and prolongation of survival time; they were mostly ineffective. Thus, SC and SAT when injected immediately at the sites of bites can reduce the systemic and local toxicity of NK and CR venoms. These results suggest that administration of these drugs at the site of venom injection may be useful in reducing venom-induced local tissue damage.

  1. Recombinant IL-33 prolongs leflunomide-mediated graft survival by reducing IFN-γ and expanding CD4(+)Foxp3(+) T cells in concordant heart transplantation.

    PubMed

    Dai, Chen; Lu, Fang-Na; Jin, Ning; Yang, Bo; Gao, Chang; Zhao, Bin; Fu, Jia-Zhao; Hong, Shi-Fu; Liang, Han-Ting; Chen, Li-Hong; Chen, Zhi-Shui; Chen, Jie; Qi, Zhong-Quan

    2016-08-01

    Interleukin (IL)-33 is a novel IL-1 family member, and its administration has been associated with promotion of T helper type-2 (Th2) cell activity and cytokines, particularly IL-4 and IL-5 in vivo. Recently, IL-33 was shown to increase CD4(+)Foxp3(+) regulatory T cells (Tregs) and to suppress levels of the Th1-type cytokine IFN-γ in allogeneic heart transplantation in mice. Therefore, we hypothesized that IL-33 and leflunomide (Lef) could prolong graft survival in the concordant mouse-to-rat heart transplantation model. In this model, xenografts undergo acute humoral xenograft rejection (AHXR) typically on day 3 or cell-mediated rejection approximately on day 7 if AHXR is inhibited by Lef treatment. Recipients were treated with Lef (n=6), IL-33 (n=6), IL-33 combined with Lef (n=6), or left untreated (n=6) for survival studies. Heart grafts were monitored until they stopped beating. Mouse heterotopic grafts were performed, and recipients were sacrificed on days 2 and 7 for histological and flow cytometric analyses. The combination of IL-33 and Lef significantly prolonged the grafts from 17.3±2.3 to 2.8±0.4 days, compared to untreated controls. IL-33 administration with Lef, while facilitating Th2-associated cytokines (IL-4 on day 2 but not day 7), also decreased IFN-γ on day 2 and day 7, compared with Lef treatment only. Furthermore, IL-33 with Lef administration caused an expansion of suppressive CD4(+)Foxp3(+) Tregs in rats. The IL-33 and Lef combination therapy resulted in significantly prolonged graft survival, associated with markedly decreased Th1 cells and increased IL-10 levels. In addition, the combination therapy significantly decreased the percentage of CD-45(+) B cells on days 2 and 7, compared with monotherapy. These findings reveal a new immunoregulatory property of IL-33. Specifically, it facilitates regulatory cells, particularly functional CD4(+)Foxp3(+) Tregs that underlie IL-33-mediated cardiac xenograft survival. Moreover, it can decrease Th

  2. Decreased expression of the Ets family transcription factor Fli-1 markedly prolongs survival and significantly reduces renal disease in MRL/lpr mice.

    PubMed

    Zhang, Xian K; Gallant, Sarah; Molano, Ivan; Moussa, Omar M; Ruiz, Phillip; Spyropoulos, Demetri D; Watson, Dennis K; Gilkeson, Gary

    2004-11-15

    Increased Fli-1 mRNA is present in PBLs from systemic lupus erythematosus patients, and transgenic overexpression of Fli-1 in normal mice leads to a lupus-like disease. We report in this study that MRL/lpr mice, an animal model of systemic lupus erythematosus, have increased splenic expression of Fli-1 protein compared with BALB/c mice. Using mice with targeted gene disruption, we examined the effect of reduced Fli-1 expression on disease development in MRL/lpr mice. Complete knockout of Fli-1 is lethal in utero. Fli-1 protein expression in heterozygous MRL/lpr (Fli-1(+/-)) mice was reduced by 50% compared with wild-type MRL/lpr (Fli-1(+/+)) mice. Fli-1(+/-) MRL/lpr mice had significantly decreased serum levels of total IgG and anti-dsDNA Abs as disease progressed. Fli-1(+/-) MRL/lpr mice had significantly increased splenic CD8(+) and naive T cells compared with Fli-1(+/+) MRL/lpr mice. Both in vivo and in vitro production of MCP-1 were significantly decreased in Fli-1(+/-) MRL/lpr mice. The Fli-1(+/-) mice had markedly decreased proteinuria and significantly lower pathologic renal scores. At 48 wk of age, survival was significantly increased in the Fli-1(+/-) MRL/lpr mice, as 100% of Fli-1(+/-) MRL/lpr mice were alive, in contrast to only 27% of Fli-1(+/+) mice. These findings indicate that Fli-1 expression is important in lupus-like disease development, and that modulation of Fli-1 expression profoundly decreases renal disease and improves survival in MRL/lpr mice.

  3. Prolonged shelf life and reduced drip loss of chicken filets by the use of carbon dioxide emitters and modified atmosphere packaging.

    PubMed

    Holck, Askild L; Pettersen, Marit K; Moen, Marie H; Sørheim, Oddvin

    2014-07-01

    Modified atmosphere packaging containing CO2 is widely used for extending the shelf life of chicken meat. Active packaging by adding CO2 emitter sachets to packages of meat is an alternative to traditional modified atmosphere packaging. The purpose of the study was to investigate the shelf life of chicken filets under different CO2 concentrations at 4°C storage. The inhibition of microbial growth was proportional to the CO2 concentration. Storage in 100% CO2 both with and without a CO2 emitter sachet gave a microbiological shelf-life extension of 7 days compared with 60% CO2. Carnobacterium divergens, Carnobacterium sp., and Lactococcus sp. were the dominating species at the end of the storage period. During storage in pure CO2, the carbon dioxide dissolved in the meat and caused the collapse of the packages. The resulting squeeze of the meat lead to a severe increase in drip loss. The drip loss was reduced profoundly by using the CO2 emitting sachet in the packages. The addition of CO2 emitters can easily be implemented at industrial packaging lines without reduction in production efficiency.

  4. Nonclassical export pathway: overexpression of NCE102 reduces protein and DNA damage and prolongs lifespan in an SGS1 deficient Saccharomyces cerevisiae.

    PubMed

    Desmyter, Liesbeth; Verstraelen, Jan; Dewaele, Sylviane; Libert, Claude; Contreras, Roland; Chen, Cuiying

    2007-10-01

    In this study, we used our recently developed screening method, Bud-Scar-based Screening (BSS), to screen a yeast cDNA expression library in an SGS1 deletion BY4742 yeast strain. One gene involved in a nonclassical export pathway, NCE102, was found to extend the life span of Deltasgs1 yeast. Deletion of NCE102 in a wild type yeast strain increased its sensitivity to oxidative stress upon diethylmaleate (DEM) treatment but did not shorten its lifespan, indicating that this gene is not essential in determining yeast lifespan. Transformation of NCE102 into either Deltance102 or Deltasgs1 strains could rescue its tolerance to DEM stress, indicating that NCE102 is protective during oxidative stress. Moreover, overexpression of NCE102 in Deltasgs1 strain leads to reduced protein damage. However, overexpression of NCE102 in wild type yeast strain BY4742 neither protected against oxidative stress due to DEM nor extended yeast lifespan compared to its parental wild type strain, indicating that nonclassical export is redundant and DNA repair is fully sufficient in the wild type strain. We therefore demonstrate that a nonclassical export pathway functions as an alternative clearance/detoxification pathway to eliminate damaged material, when the basic repair pathway is not sufficient.

  5. Human muscle net K(+) release during exercise is unaffected by elevated anaerobic metabolism, but reduced after prolonged acclimatization to 4,100 m.

    PubMed

    Nordsborg, Nikolai B; Calbet, José A L; Sander, Mikael; van Hall, Gerrit; Juel, Carsten; Saltin, Bengt; Lundby, Carsten

    2010-07-01

    It was investigated whether skeletal muscle K(+) release is linked to the degree of anaerobic energy production. Six subjects performed an incremental bicycle exercise test in normoxic and hypoxic conditions prior to and after 2 and 8 wk of acclimatization to 4,100 m. The highest workload completed by all subjects in all trials was 260 W. With acute hypoxic exposure prior to acclimatization, venous plasma [K(+)] was lower (P < 0.05) in normoxia (4.9 +/- 0.1 mM) than hypoxia (5.2 +/- 0.2 mM) at 260 W, but similar at exhaustion, which occurred at 400 +/- 9 W and 307 +/- 7 W (P < 0.05), respectively. At the same absolute exercise intensity, leg net K(+) release was unaffected by hypoxic exposure independent of acclimatization. After 8 wk of acclimatization, no difference existed in venous plasma [K(+)] between the normoxic and hypoxic trial, either at submaximal intensities or at exhaustion (360 +/- 14 W vs. 313 +/- 8 W; P < 0.05). At the same absolute exercise intensity, leg net K(+) release was less (P < 0.001) than prior to acclimatization and reached negative values in both hypoxic and normoxic conditions after acclimatization. Moreover, the reduction in plasma volume during exercise relative to rest was less (P < 0.01) in normoxic than hypoxic conditions, irrespective of the degree of acclimatization (at 260 W prior to acclimatization: -4.9 +/- 0.8% in normoxia and -10.0 +/- 0.4% in hypoxia). It is concluded that leg net K(+) release is unrelated to anaerobic energy production and that acclimatization reduces leg net K(+) release during exercise.

  6. Delayed Satiety-Like Actions and Altered Feeding Microstructure by a Selective Type 2 Corticotropin-Releasing Factor Agonist in Rats: Intra-Hypothalamic Urocortin 3 Administration Reduces Food Intake by Prolonging the Post-Meal Interval

    PubMed Central

    Fekete, Éva M; Inoue, Koki; Zhao, Yu; Rivier, Jean E; Vale, Wylie W; Szücs, Attila; Koob, George F; Zorrilla, Eric P

    2009-01-01

    Brain corticotropin-releasing factor/urocortin (CRF/Ucn) systems are hypothesized to control feeding, with central administration of ‘type 2’ urocortins producing delayed anorexia. The present study sought to identify the receptor subtype, brain site, and behavioral mode of action through which Ucn 3 reduces nocturnal food intake in rats. Non-food-deprived male Wistar rats (n = 176) were administered Ucn 3 into the lateral (LV) or fourth ventricle, or into the ventromedial or paraventricular nuclei of the hypothalamus (VMN, PVN) or the medial amygdala (MeA), regions in which Ucn 3 is expressed in proximity to CRF2 receptors. LV Ucn 3 suppressed ingestion during the third–fourth post-injection hours. LV Ucn 3 anorexia was reversed by cotreatment with astressin2-B, a selective CRF2 antagonist and not observed following equimole subcutaneous or fourth ventricle administration. Bilateral intra-VMN and intra-PVN infusion, more potently than LV infusion, reduced the quantity (57–73%) and duration of ingestion (32–68%) during the third–fourth post-infusion hours. LV, intra-PVN and intra-VMN infusion of Ucn 3 slowed the eating rate and reduced intake by prolonging the post-meal interval. Intra-VMN Ucn 3 reduced feeding bout size, and intra-PVN Ucn 3 reduced the regularity of eating from pellet to pellet. Ucn 3 effects were behaviorally specific, because minimal effective anorectic Ucn 3 doses did not alter drinking rate or promote a conditioned taste aversion, and site-specific, because intra-MeA Ucn 3 produced a nibbling pattern of more, but smaller meals without altering total intake. The results implicate the VMN and PVN of the hypothalamus as sites for Ucn 3-CRF2 control of food intake. PMID:17019404

  7. Survival in a rat model of lethal hemorrhagic shock is prolonged following resuscitation with a small volume of a solution containing a drag-reducing polymer derived from aloe vera.

    PubMed

    Macias, Carlos A; Kameneva, Marina V; Tenhunen, Jyrki J; Puyana, Juan-Carlos; Fink, Mitchell P

    2004-08-01

    Drag-reducing polymers (DRP) increase tissue perfusion at constant driving pressure. We sought to evaluate the effects of small-volume resuscitation with a solution containing a DRP in a rat model of hemorrhage. Anesthetized rats were hemorrhaged at a constant rate over 25 min. In protocol A, total blood loss was 2.45 mL/100 g, whereas in protocol B, total blood loss was 3.15 mL/100 g. Five minutes after hemorrhage, the animals were resuscitated with 7 mL/kg of either normal saline (NS) or NS containing 50 microg/mL of an aloe vera-derived DRP. In protocol B, a third group (CON) was not resuscitated. Whole-body O2 consumption (Vo2) and CO2 production (Vco2) were measured using indirect calorimetry. In protocol A, 5/10 rats in the NS group and 8/10 rats in the DRP group survived for 4 h (P = 0.14). Mean arterial pressure was higher in the DRP-treated group than in the NS-treated group 45 min after resuscitation (89 +/- 8 vs. 68 +/- 5 mmHg, respectively; P < 0.05). In protocol B, survival rates over 2 h in the DRP, NS, and CON groups were 5/15, 1/14, and 0/7, respectively (P < 0.05). Compared with NS-treated rats, those resuscitated with DRP achieved a higher peak Vo2 (9.0 +/- 1.0 vs. 6,3+/- 1.0 mL/kg/min) and Vco2 (9.0 +/- 1.1 vs. 6.0 +/- 1.0 mL/kg/min) after resuscitation. We conclude that resuscitation with a small volume of DRP prolongs survival in rats with lethal hemorrhagic shock.

  8. IMC-EB10, an anti-FLT3 monoclonal antibody, prolongs survival and reduces nonobese diabetic/severe combined immunodeficient engraftment of some acute lymphoblastic leukemia cell lines and primary leukemic samples.

    PubMed

    Piloto, Obdulio; Nguyen, Bao; Huso, David; Kim, Kyu-Tae; Li, Yiwen; Witte, Larry; Hicklin, Daniel J; Brown, Patrick; Small, Donald

    2006-05-01

    The class III receptor tyrosine kinase FLT3 is expressed on the blasts of >90% of patients with B-lineage acute lymphoblastic leukemias (ALL). In addition, it is expressed at extremely high levels in ALL patients with mixed lineage leukemia rearrangements or hyperdiploidy and is sometimes mutated in these same patients. In this report, we investigate the effects of treating ALL cell lines and primary samples with human anti-FLT3 monoclonal antibodies (mAb) capable of preventing binding of FLT3 ligand. In vitro studies, examining the ability of two anti-FLT3 mAbs (IMC-EB10 and IMC-NC7) to affect FLT3 activation and downstream signaling in ALL cell lines and primary blasts, yielded variable results. FLT3 phosphorylation was consistently inhibited by IMC-NC7 treatment, but in some cell lines, IMC-EB10 actually stimulated FLT3 activation, possibly as a result of antibody-mediated receptor dimerization. Through antibody-dependent, cell-mediated cytotoxicity, such an antibody could still prove efficacious against leukemia cells in vivo. In fact, IMC-EB10 treatment significantly prolonged survival and/or reduced engraftment of several ALL cell lines and primary ALL samples in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. This occurred even when IMC-EB10 treatment resulted in FLT3 activation in vitro. Moreover, fluorescence-activated cell sorting and PCR analysis of IMC-EB10-treated NOD/SCID mice surviving 150 days post-leukemic cell injection revealed that FLT3 immunotherapy reduced leukemic engraftment below the level of detection in these assays (<0.001%). Furthermore, in vivo IMC-EB10 treatment did not select for resistant cells, because cells surviving IMC-EB10 treatment remain sensitive to IMC-EB10 cytotoxicity upon retransplantation. In vivo studies involving either partial depletion or activation of natural killer (NK) cells show that most of the cytotoxic effect of IMC-EB10 is mediated through NK cells. Therefore, such an antibody, either

  9. Deciding about treatments that prolong life

    MedlinePlus

    Palliative care - treatments that prolong life; Palliative care - life support; End-of-life-treatments that prolong life; Ventilator - treatments that prolong life; Respirator - treatments that prolong life; Life-support - treatments ...

  10. Acute prolongation of myocardial refractoriness by sotalol.

    PubMed Central

    Bennett, D H

    1982-01-01

    Sotalol, a beta adrenoceptor antagonist, was given intravenously to 15 patients with accessory atrioventricular pathways during intracardiac electrophysiological studies. Eleven patients had the Wolff-Parkinson-White syndrome and four patients had concealed left sided accessory pathways. Four patients were restudied while receiving oral sotalol. In contrast to the actions typical of beta blocking agents, intravenous sotalol prolonged the effective refractory periods of the ventricles and accessory pathways and reduced the ventricular response to atrial fibrillation in the patients with the Wolff-Parkinson-White syndrome. Similar results were obtained with oral administration. These findings support the observation that sotalol, unlike other beta blocking agents. causes acute prolongation of the myocardial action potential and suggest that this action might be of therapeutic use. PMID:7082500

  11. Inhibition in Prolonged Work Tasks.

    ERIC Educational Resources Information Center

    van der Ven, A. H. G. S.; And Others

    1989-01-01

    A new model is presented that explains reaction time fluctuations in prolonged work tasks. The model extends the so-called Poisson-Erlang model and accounts for long-term trend effects in the reaction time curve. The model is consistent with Spearman's hypothesis that inhibition increases during work and decreases during rest. (TJH)

  12. Physiology Of Prolonged Bed Rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.

    1991-01-01

    Report describes physiological effects of prolonged bed rest. Rest for periods of 24 hours or longer deconditions body to some extent; healing proceeds simultaneously with deconditioning. Report provides details on shifts in fluid electrolytes and loss of lean body mass, which comprises everything in body besides fat - that is, water, muscle, and bone. Based on published research.

  13. Exemestane Following Tamoxifen Reduces Breast Cancer Recurrences and Prolongs Survival

    Cancer.gov

    Postmenopausal women with early-stage hormone receptor-positive breast cancer had delayed disease recurrence and longer survival after taking 2-3 years of tamoxifen followed by exemestane for a total of 5 years compared to taking tamoxifen for 5 years.

  14. Moving frames and prolongation algebras

    NASA Technical Reports Server (NTRS)

    Estabrook, F. B.

    1982-01-01

    Differential ideals generated by sets of 2-forms which can be written with constant coefficients in a canonical basis of 1-forms are considered. By setting up a Cartan-Ehresmann connection, in a fiber bundle over a base space in which the 2-forms live, one finds an incomplete Lie algebra of vector fields in the fields in the fibers. Conversely, given this algebra (a prolongation algebra), one can derive the differential ideal. The two constructs are thus dual, and analysis of either derives properties of both. Such systems arise in the classical differential geometry of moving frames. Examples of this are discussed, together with examples arising more recently: the Korteweg-de Vries and Harrison-Ernst systems.

  15. Sponsored parachute jumps--can they cause prolonged pain?

    PubMed

    Straiton, N; Sterland, J

    1986-06-01

    A survey of parachute injuries sustained in 1984 at a local parachute club was made using hospital notes and a questionnaire. The overall injury rate was 0.2%. The injury rate in first time jumpers was 1.1%. The injuries often resulted in a prolonged hospital stay, time off work and residual pain and disability. Injury rates may be reduced by more prolonged and intensive training preceding the first jumps. Those people not interested in parachuting as a regular sport and who jump once only in order to raise money for charity are at risk of serious injury and perhaps should consider less dangerous alternatives.

  16. Prolonged Cortisol Reactivity to Stress and White Matter in Schizophrenia

    PubMed Central

    Nugent, Katie L.; Chiappelli, Joshua; Sampath, Hemalatha; Rowland, Laura M.; Thangavelu, Kavita; Davis, Beshaun; Du, Xiaoming; Muellerklein, Florian; Daughters, Stacey; Kochunov, Peter; Hong, L. Elliot

    2015-01-01

    Objective While acute hypothalamic-pituitary-adrenal axis response to stress is often adaptive, prolonged responses may have detrimental effects. Many components of white matter structures are sensitive to prolonged cortisol exposure. We aimed to identify a behavioral laboratory assay for which cortisol response related to brain pathophysiology in schizophrenia. We hypothesized that an abnormally prolonged cortisol response to stress may be linked to abnormal white matter integrity in patients with schizophrenia. Methods Acute and prolonged salivary cortisol response was measured outside the scanner at pre-test and then at 0, 20, and 40 minutes after a psychological stress task in patients with schizophrenia (n=45) and controls (n=53). Tract-averaged white matter was measured by 64-direction diffusion tensor imaging in a subset of patients (n=30) and controls (n=33). Results Patients who did not tolerate and quit the psychological stress task had greater acute (t=2.52, p=0.016; t=3.51, p=0.001 at zero and 20 minutes) and prolonged (t=3.62, p=0.001 at 40 minutes) cortisol reactivity compared with patients who finished the task. Abnormally prolonged cortisol reactivity in patients was significantly associated with reduced white matter integrity (r=−0.468, p=0.009). Regardless of task completion status, acute cortisol response was not related to the white matter measures in patients or controls. Conclusions This paradigm was successful at identifying a subset of patients whose cortisol response was associated with brain pathophysiology. Abnormal cortisol response may adversely affect white matter integrity, partly explaining this pathology observed in schizophrenia. Prolonged stress responses may be targeted for intervention to test for protective effects against white matter damages. PMID:26186431

  17. Physiology of prolonged bed rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1988-01-01

    Bed rest has been a normal procedure used by physicians for centuries in the treatment of injury and disease. Exposure of patients to prolonged bed rest in the horizontal position induces adaptive deconditioning responses. While deconditioning responses are appropriate for patients or test subjects in the horizontal position, they usually result in adverse physiological responses (fainting, muscular weakness) when the patient assume the upright posture. These deconditioning responses result from reduction in hydrostatic pressure within the cardiovascular system, virtual elimination of longitudinal pressure on the long bones, some decrease in total body metabolism, changes in diet, and perhaps psychological impact from the different environment. Almost every system in the body is affected. An early stimulus is the cephalic shift of fluid from the legs which increases atrial pressure and induces compensatory responses for fluid and electrolyte redistribution. Without countermeasures, deterioration in strength and muscle function occurs within 1 wk while increased calcium loss may continue for months. Research should also focus on drug and carbohydrate metabolism.

  18. Drug-induced QT interval prolongation and torsades de pointes

    PubMed Central

    Tisdale, James E.

    2016-01-01

    Torsades de pointes (TdP) is a life-threatening arrhythmia associated with prolongation of the corrected QT (QTc) interval on the electrocardiogram. More than 100 drugs available in Canada, including widely used antibiotics, antidepressants, cardiovascular drugs and many others, may cause QTc interval prolongation and TdP. Risk factors for TdP include QTc interval >500 ms, increase in QTc interval ≥60 ms from the pretreatment value, advanced age, female sex, acute myocardial infarction, heart failure with reduced ejection fraction, hypokalemia, hypomagnesemia, hypocalcemia, bradycardia, treatment with diuretics and elevated plasma concentrations of QTc interval–prolonging drugs due to drug interactions, inadequate dose adjustment of renally eliminated drugs in patients with kidney disease and rapid intravenous administration. Pharmacokinetic drug interactions associated with the highest risk of TdP include antifungal agents, macrolide antibiotics (except azithromycin) and drugs to treat human immunodeficiency virus interacting with amiodarone, disopyramide, dofetilide or pimozide. Other important pharmacokinetic interactions include antidepressants (bupropion, duloxetine, fluoxetine, paroxetine) interacting with flecainide, quinidine or thioridazine. Pharmacists play an important role in minimizing the risk of drug-induced QTc interval prolongation and TdP through knowledge of drugs that are associated with a known or possible risk of TdP, individualized assessment of risk of drug-induced QTc interval prolongation, awareness of drug interactions most likely to result in TdP and attention to dose reduction of renally eliminated QTc interval-prolonging drugs in patients with kidney disease. Treatment of hemodynamically stable TdP consists of discontinuation of the offending drug(s), correction of electrolyte abnormalities and administration of intravenous magnesium sulfate 1 to 2 g. PMID:27212965

  19. Deep, prolonged torpor by pregnant, free-ranging bats

    NASA Astrophysics Data System (ADS)

    Willis, Craig K. R.; Brigham, R. Mark; Geiser, Fritz

    2006-02-01

    Many mammals save energy during food shortage or harsh weather using controlled reductions in body temperature and metabolism called torpor. However, torpor slows offspring growth, and reproductive individuals are thought to avoid using it because of reduced fitness resulting from delayed offspring development. We tested this hypothesis by investigating torpor during reproduction in hoary bats ( Lasiurus cinereus, Vespertilionidae) in southern Canada. We recorded deep, prolonged torpor bouts, which meet the definition for hibernation, by pregnant females. Prolonged torpor occurred during spring storms. When conditions improved females aroused and gave birth within several days. Our observations imply a fitness advantage of torpor in addition to energy conservation because reduced foetal growth rate could delay parturition until conditions are more favourable for lactation and neonatal survival.

  20. [A case of prolonged paroxysmal sympathetic hyperactivity].

    PubMed

    Yamamoto, Akiko; Ide, Shuhei; Iwasaki, Yuji; Kaga, Makiko; Arima, Masataka

    2016-03-01

    We report the case of a 4-year-old girl who presented with paroxysmal sympathetic hyperactivity (PSH), after developing severe hypoxic-ischemic-encephalopathy because of cardiopulmonary arrest. She showed dramatic paroxysmal sympathetic activity with dystonia. She was treated with wide variety of medications against PSH, which were found to be effective in previous studies. Among them, morphine, bromocriptine, propranolol, and clonidine were effective in reducing the frequency of her attacks while gabapentin, baclofen, dantrolene, and benzodiazepine were ineffective. Though the paroxysms decreased markedly after the treatment, they could not be completely controlled beyond 500 days. Following the treatment, levels of plasma catecholamines and their urinary metabolites decreased to normal during inter- paroxysms. However, once a paroxysm had recurred, these levels were again very high. This case study is considered significant for two rea- sons. One is that PSH among children have been rarely reported, and the other is that this case of prolonged PSH delineated the transition of plasma catecholamines during the treatment. The excitatory: inhibitory ratio (EIR) model proposed by Baguley was considered while dis- cussing drug sensitivity in this case. Accumulation of similar case studies will help establish more effective treatment strategies and elucidate the pathophysiology of PSH.

  1. Prolonged partial epilepsy: a case report

    SciTech Connect

    Wilson, M.A.

    1980-11-01

    The case study of a patient with prolonged partial epilepsy is presented. There was a discrepancy between the extent of the abnormality seen on the radionuclide angiogram and that seen on the static brain scan.

  2. QT Prolongation due to Graves' Disease

    PubMed Central

    Deol, Nisha; Tolly, Renee; Manocha, Rohan; Naseer, Maliha

    2017-01-01

    Hyperthyroidism is a highly prevalent disease affecting over 4 million people in the US. The disease is associated with many cardiac complications including atrial fibrillation and also less commonly with ventricular tachycardia and fibrillation. Many cardiac pathologies have been extensively studied; however, the relationship between hyperthyroidism and rate of ventricular repolarization manifesting as a prolonged QTc interval is not well known. Prolonged QTc interval regardless of thyroid status is a risk factor for cardiovascular mortality and life-threatening ventricular arrhythmia. The mechanism regarding the prolongation of the QT interval in a hyperthyroid patient has not been extensively investigated although its clinical implications are relevant. Herein, we describe a case of prolonged QTc in a patient who presented with signs of hyperthyroidism that was corrected with return to euthyroid status. PMID:28154763

  3. Prolonged swimming performance of northern squawfish

    USGS Publications Warehouse

    Mesa, Matthew G.; Olson, Todd M.

    1993-01-01

    We determined the prolonged swimming performance of two size-classes of northern squawfish Ptychocheilus oregonensis at 12 and 18°C. The percentage of fish fatigued was positively related to water velocity and best described by an exponential model. At 12°C, the velocity at which 50% of the fish fatigued (FV50) was estimated to be 2.91 fork lengths per second (FL/s; 100 cm/s) for medium-sized fish (30–39 cm) and 2.45 FL/s (104 cm/s) for large fish (40–49 cm). At 18°C, estimated FV50 was 3.12 FL/s (107 cm/s) for medium fish and 2.65 FL/s (112 cm/s) for large fish. Rate of change in percent fatigue was affected by fish size and water temperature. Large fish fatigued at a higher rate than medium-sized fish; all fish fatigued faster at 12 than at 18°C. The mean times to fatigue at velocities of 102–115 cm/s ranged from 14 to 28 min and were not affected by fish size or water temperature. Our results indicate that water velocities from 100 to 130 cm/s may exclude or reduce predation by northern squawfish around juvenile salmonid bypass outfalls at Columbia River dams, at least during certain times of the year. We recommend that construction or modification of juvenile salmonid bypass facilities place the outfall in an area of high water velocity and distant from eddies, submerged cover, and littoral areas.

  4. Management of children with prolonged diarrhea

    PubMed Central

    Giannattasio, Antonietta; Guarino, Alfredo; Lo Vecchio, Andrea

    2016-01-01

    Prolonged diarrhea is usually defined as acute-onset diarrhea lasting 7 days or more, but less than 14 days. Its trend has been declining in recent years because of improvement in the management of acute diarrhea, which represents the ideal strategy to prevent prolonged diarrhea. The pathogenesis of prolonged diarrhea is multifactorial and essentially based on persistent mucosal damage due to specific infections or sequential infections with different pathogens, host-related factors including micronutrient and/or vitamin deficiency, undernutrition and immunodeficiency, high mucosal permeability due to previous infectious processes and nutrient deficiency with consequential malabsorption, and microbiota disruption. Infections seem to play a major role in causing prolonged diarrhea in both developing and developed areas. However, single etiologic pathogens have not been identified, and the pattern of agents varies according to settings, host risk factors, and previous use of antibiotics and other drugs. The management of prolonged diarrhea is complex. Because of the wide etiologic spectrum, diagnostic algorithms should take into consideration the age of the patient, clinical and epidemiological factors, and the nutritional status and should always include a search for enteric pathogens. Often, expensive laboratory evaluations are of little benefit in guiding therapy, and an empirical approach may be effective in the majority of cases. The presence or absence of weight loss is crucial for driving the initial management of prolonged diarrhea. If there is no weight loss, generally there is no need for further evaluation. If weight loss is present, empiric anti-infectious therapy or elimination diet may be considered once specific etiologies have been excluded. PMID:26962439

  5. Prosthodontic Approach in Management of Prolonged Neonatal Intubation

    PubMed Central

    Shah, Shital K; Rathod, Vishnu B; Ambadkar, Priyanka S; Patil, Charudutt N

    2016-01-01

    Intubation is a routine intervention in the Neonatal Intensive Care Unit (NICU) for preterm neonates with respiratory distress, inadequate gag reflex, poor sucking and swallowing. Prolonged intubation in neonates can be done by nasal or oral route. Although naso-tracheal intubation may reduce movement of the tube, it may contribute to airway obstruction, possible hypoxia, and occlusion of the nasal aperture during a crucial period of development further contributing to laboured breathing. Being obligate nasal breathers, oro-tracheal route is the preferred method of intubation in premature infants as oral mucosa is less susceptible to damage than nasal mucosa. Ineffective stabilization of the tubes is a frequent problem often resulting in accidental extubation and displacement of orotracheal and orogastric tube. Hence, these tubes must be stabilized against displacement from tongue and jaw movements to prevent discomfort and subsequent tissue trauma. Complications of prolonged endotracheal intubation include palatal groove formation by pressure against the hard palate, infection, accidental extubation, malposition, laryngeal or tracheal edema and ulceration, tracheal stenosis, vocal cord injury. Various oral appliances are used for infants to stabilize the tubes and prevent complications associated with long term intubation. This case report describes a prosthodontic approach in management of prolonged neonatal intubation. PMID:28050517

  6. Prosthodontic Approach in Management of Prolonged Neonatal Intubation.

    PubMed

    Kamble, Vikas B; Shah, Shital K; Rathod, Vishnu B; Ambadkar, Priyanka S; Patil, Charudutt N

    2016-11-01

    Intubation is a routine intervention in the Neonatal Intensive Care Unit (NICU) for preterm neonates with respiratory distress, inadequate gag reflex, poor sucking and swallowing. Prolonged intubation in neonates can be done by nasal or oral route. Although naso-tracheal intubation may reduce movement of the tube, it may contribute to airway obstruction, possible hypoxia, and occlusion of the nasal aperture during a crucial period of development further contributing to laboured breathing. Being obligate nasal breathers, oro-tracheal route is the preferred method of intubation in premature infants as oral mucosa is less susceptible to damage than nasal mucosa. Ineffective stabilization of the tubes is a frequent problem often resulting in accidental extubation and displacement of orotracheal and orogastric tube. Hence, these tubes must be stabilized against displacement from tongue and jaw movements to prevent discomfort and subsequent tissue trauma. Complications of prolonged endotracheal intubation include palatal groove formation by pressure against the hard palate, infection, accidental extubation, malposition, laryngeal or tracheal edema and ulceration, tracheal stenosis, vocal cord injury. Various oral appliances are used for infants to stabilize the tubes and prevent complications associated with long term intubation. This case report describes a prosthodontic approach in management of prolonged neonatal intubation.

  7. Effect of sleep deprivation on tolerance of prolonged exercise.

    PubMed

    Martin, B J

    1981-01-01

    Acute loss of sleep produces few apparent physiological effects at rest. Nevertheless, many anecdotes suggest that adequate sleep is essential for optimum endurance athletic performance. To investigate this question, heavy exercise performance after 36 h without sleep was compared with that after normal sleep in eight subjects. During prolonged treadmill walking at about 80% of the VO2 max, sleep loss reduced work time to exhaustion by an average of 11% (p = 0.05). This decrease occurred despite doubling monetary incentives for subjects during work after sleeplessness. Subjects appeared to fall into "resistant" and "susceptible" categories: four showed less than a 5% change in performance after sleep loss, while four others showed decrements in exercise tolerance ranging from 15 to 40%. During the walk, sleep loss resulted in significantly greater perceived exertion (p less than 0.05), even though exercise heart rate and metabolic rate (VO2 and VCO2) were unchanged. Minute ventilation was significantly elevated during exercise after sleep loss ( p less than 0.05). Sleep loss failed to alter the continuous slow rises in VE and heart rate that occurred as work was prolonged. These findings suggest that the psychological effects of acute sleep loss may contribute to decreased tolerance of prolonged heavy exercise.

  8. Prolongation structures of nonlinear evolution equations

    NASA Technical Reports Server (NTRS)

    Wahlquist, H. D.; Estabrook, F. B.

    1975-01-01

    A technique is developed for systematically deriving a 'prolongation structure' - a set of interrelated potentials and pseudopotentials - for nonlinear partial differential equations in two independent variables. When this is applied to the Korteweg-de Vries equation, a new infinite set of conserved quantities is obtained. Known solution techniques are shown to result from the discovery of such a structure: related partial differential equations for the potential functions, linear 'inverse scattering' equations for auxiliary functions, Backlund transformations. Generalizations of these techniques will result from the use of irreducible matrix representations of the prolongation structure.

  9. Comparing Virtual Reality Exposure Therapy to Prolonged Exposure in the Treatment of Soldiers with PTSD

    DTIC Science & Technology

    2014-06-01

    researched psychotherapies for PTSD. Virtual reality exposure (VRE) has demonstrated growing support as an innovative method for activating the trauma...related trauma that met criteria for PTSD according to the CAPS. Participants also had to agree not to initiate other psychotherapy for PTSD or new...1. Psychotherapy that used prolonged or virtual reality-enhanced prolonged exposure (VR) would reduce the clinical symptoms of PTSD to a greater

  10. Tetrodotoxin-bupivacaine-epinephrine combinations for prolonged local anesthesia.

    PubMed

    Berde, Charles B; Athiraman, Umeshkumar; Yahalom, Barak; Zurakowski, David; Corfas, Gabriel; Bognet, Christina

    2011-12-01

    Currently available local anesthetics have analgesic durations in humans generally less than 12 hours. Prolonged-duration local anesthetics will be useful for postoperative analgesia. Previous studies showed that in rats, combinations of tetrodotoxin (TTX) with bupivacaine had supra-additive effects on sciatic block durations. In those studies, epinephrine combined with TTX prolonged blocks more than 10-fold, while reducing systemic toxicity. TTX, formulated as Tectin, is in phase III clinical trials as an injectable systemic analgesic for chronic cancer pain. Here, we examine dose-duration relationships and sciatic nerve histology following local nerve blocks with combinations of Tectin with bupivacaine 0.25% (2.5 mg/mL) solutions, with or without epinephrine 5 µg/mL (1:200,000) in rats. Percutaneous sciatic blockade was performed in Sprague-Dawley rats, and intensity and duration of sensory blockade was tested blindly with different Tectin-bupivacaine-epinephrine combinations. Between-group comparisons were analyzed using ANOVA and post-hoc Sidak tests. Nerves were examined blindly for signs of injury. Blocks containing bupivacaine 0.25% with Tectin 10 µM and epinephrine 5 µg/mL were prolonged by roughly 3-fold compared to blocks with bupivacaine 0.25% plain (P < 0.001) or bupivacaine 0.25% with epinephrine 5 µg/mL (P < 0.001). Nerve histology was benign for all groups. Combinations of Tectin in bupivacaine 0.25% with epinephrine 5 µg/mL appear promising for prolonged duration of local anesthesia.

  11. Prolonged Soil Frost Affects Hydraulics and Phenology of Apple Trees

    PubMed Central

    Beikircher, Barbara; Mittmann, Claudia; Mayr, Stefan

    2016-01-01

    Restoration of an adequate water supply in spring is a prerequisite for survival of angiosperm trees in temperate regions. Trees must re-establish access to soil water and recover xylem functionality. We thus hypothesized that prolonged soil frost impairs recovery and affects hydraulics and phenology of Malus domestica var. ‘Golden Delicious.’ To test this hypothesis, over two consecutive winters the soil around some trees was insulated to prolong soil frosting, From mid-winter to early summer, the level of native embolism, the water and starch contents of wood, bark and buds were quantified at regular intervals and findings correlated with various phenological parameters, xylogenesis and fine root growth. The findings confirm that prolonged soil frost affects tree hydraulics and phenology but the severity of the effect depends on the climatic conditions. In both study years, percentage loss of hydraulic conductivity (PLC) decreased from about 70% at the end of winter to about 10% in May. Thereby, xylem refilling strongly coincided with a decrease of starch in wood and bark. Also treated trees were able to restore their hydraulic system by May but, in the warm spring of 2012, xylem refilling, the increases in water content and starch depolymerization were delayed. In contrast, in the cold spring of 2013 only small differences between control and treated trees were observed. Prolongation of soil frost also led to a delay in phenology, xylogenesis, and fine root growth. We conclude that reduced water uptake from frozen or cold soils impairs refilling and thus negatively impacts tree hydraulics and growth of apple trees in spring. Under unfavorable circumstances, this may cause severe winter damage or even dieback. PMID:27379146

  12. Prolonged Soil Frost Affects Hydraulics and Phenology of Apple Trees.

    PubMed

    Beikircher, Barbara; Mittmann, Claudia; Mayr, Stefan

    2016-01-01

    Restoration of an adequate water supply in spring is a prerequisite for survival of angiosperm trees in temperate regions. Trees must re-establish access to soil water and recover xylem functionality. We thus hypothesized that prolonged soil frost impairs recovery and affects hydraulics and phenology of Malus domestica var. 'Golden Delicious.' To test this hypothesis, over two consecutive winters the soil around some trees was insulated to prolong soil frosting, From mid-winter to early summer, the level of native embolism, the water and starch contents of wood, bark and buds were quantified at regular intervals and findings correlated with various phenological parameters, xylogenesis and fine root growth. The findings confirm that prolonged soil frost affects tree hydraulics and phenology but the severity of the effect depends on the climatic conditions. In both study years, percentage loss of hydraulic conductivity (PLC) decreased from about 70% at the end of winter to about 10% in May. Thereby, xylem refilling strongly coincided with a decrease of starch in wood and bark. Also treated trees were able to restore their hydraulic system by May but, in the warm spring of 2012, xylem refilling, the increases in water content and starch depolymerization were delayed. In contrast, in the cold spring of 2013 only small differences between control and treated trees were observed. Prolongation of soil frost also led to a delay in phenology, xylogenesis, and fine root growth. We conclude that reduced water uptake from frozen or cold soils impairs refilling and thus negatively impacts tree hydraulics and growth of apple trees in spring. Under unfavorable circumstances, this may cause severe winter damage or even dieback.

  13. Carotid Baroreflex Function During Prolonged Exercise

    NASA Technical Reports Server (NTRS)

    Raven, P. B.

    1999-01-01

    Astronauts are often required to work (exercise) at moderate to high intensities for extended periods while performing extra-vehicular activities (EVA). Although the physiologic responses associated with prolonged exercise have been documented, the mechanisms involved in blood pressure regulation under these conditions have not yet been fully elucidated. An understanding of this issue is pertinent to the ability of humans to perform work in microgravity and complies with the emphasis of NASA's Space Physiology and Countermeasures Program. Prolonged exercise at a constant workload is know to result in a progressive decrease in mean arterial pressure (MAP) concomitant with a decrease in stroke volume and a compensatory increase in heart rate. The continuous decrease in MAP during the exercise, which is related to the thermoregulatory redistribution of circulating blood volume to the cutaneous circulation, raises the question as to whether there is a loss of baroreflex regulation of arterial blood pressure. We propose that with prolongation of the exercise to 60 minutes, progressive increases on central command reflect a progressive upward resetting of the carotid baroreflex (CBR) such that the operating point of the CBR is shifted to a pressure below the threshold of the reflex rendering it ineffectual in correcting the downward drift in MAP. In order to test this hypothesis, experiments have been designed to uncouple the global hemodynamic response to prolonged exercise from the central command mediated response via: (1) continuous maintenance of cardiac filling volume by intravenous infusion of a dextran solution; and (2) whole body surface cooling to counteract thermoregulatory cutaneous vasodialation. As the type of work (exercise) performed by astronauts is inherently arm and upper body dependent, we will also examine the physiologic responses to prolonged leg cycling and arm ergometry exercise in the supine positions with and without level lower body negative

  14. Effects of the prolonged vertical tube on the separation performance of a cyclone.

    PubMed

    Qian, Fuping; Zhang, Jiguang; Zhang, Mingyao

    2006-08-25

    This article aims at the gas flow into the dustbin of conventional cyclones, the prolonged cyclone (attaching a vertical tube at the bottom of the dust outlet) is proposed by some researchers, which can make flow with dust enter into the tube and separate further. The Reynolds stress transport model (RSTM) has been employed to predict the gas flow fields of the conventional and prolonged cyclones. The tangential velocity, axial velocity profiles and turbulent kinetic energy profiles are presented, and the downward flow rates into the dustbin of the three cyclones are compared. The separation performances of these three cyclones are tested. The result indicates that the tangential velocity, axial velocity and turbulent kinetic energy in the dustbin reduce greatly when the prolonged vertical tube attaching into the dust outlet, which can avoid the re-entrainment of already separated dust effectively. Furthermore, the prolonged vertical tube increases the separation space of dusts. The downward flow rate into the dustbin of the prolonged cyclone decreases compared with the conventional cyclone. The experimental results show that the prolonged vertical tube can improve the separation efficiency by a slightly increased pressure drop. However, for an even longer tube, the separation efficiency is slightly reduced. Thus, there is an optimal tube length for a given cyclone.

  15. Status of vestibular function after prolonged bedrest

    NASA Astrophysics Data System (ADS)

    Burgeat, M.; Toupet, M.; Loth, D.; Ingster, I.; Guell, A.; Coll, J.

    6 young, healthy, male volunteers were submitted to one week of head down (-4°) bedrest. This position simulates the cerebral hemodynamic conditions in weightlessness. Measurements of vestibular equilibrium and of oculomotor system function were made before and after the prolonged bedrest. Analysis of the results indicates that vestibular responses, as measured by the maximal speed of the slow phase of the provoked nystagmus (caloric and sinusoidal rotatory stimulations), are decreased after prolonged bedrest. This statistically significant diminution requires confirmation with a greater number of cases. The reflex conflicting or interacting with the cervico-ocular and optokinetic reflexes on the one hand and the foveal vision on the other, is one of several possible explanations for the observed changes.

  16. Severe bradycardia and prolonged hypotension in ciguatera.

    PubMed

    Chan, Thomas Yan Keung

    2013-06-01

    Ciguatera results when ciguatoxin-contaminated coral reef fish from tropical or subtropical waters are consumed. The clinical features that present in affected persons are mainly gastrointestinal, neurological, general, and much less commonly, cardiovascular. We report the case of a 50-year-old man who developed the characteristic combination of acute gastrointestinal and neurological symptoms after the consumption of an unidentified coral reef fish head. In addition to those symptoms, he developed dizziness, severe bradycardia (46 bpm) and prolonged hypotension, which required the administration of intravenous atropine and over three days of intravenous fluid replacement with dopamine infusion. Patients with ciguatera can develop severe bradycardia and prolonged hypotension. Physicians should recognise the possible cardiovascular complications of ciguatera and promptly initiate treatment with intravenous atropine, intravenous fluid replacement and inotropic therapy if such complications are observed.

  17. Prolonged preconditioning with natural honey against myocardial infarction injuries.

    PubMed

    Eteraf-Oskouei, Tahereh; Shaseb, Elnaz; Ghaffary, Saba; Najafi, Moslem

    2013-07-01

    Potential protective effects of prolonged preconditioning with natural honey against myocardial infarction were investigated. Male Wistar rats were pre-treated with honey (1%, 2% and 4%) for 45 days then their hearts were isolated and mounted on a Langendorff apparatus and perfused with a modified Krebs-Henseleit solution during 30 min regional ischemia fallowed by 120 min reperfusion. Two important indexes of ischemia-induced damage (infarction size and arrhythmias) were determined by computerized planimetry and ECG analysis, respectively. Honey (1% and 2%) reduced infarct size from 23±3.1% (control) to 9.7±2.4 and 9.5±2.3%, respectively (P<0.001). At the ischemia, honey (1%) significantly reduced (P<0.05) the number and duration of ventricular tachycardia (VT). Honey (1% and 2%) also significantly decreased number of ventricular ectopic beats (VEBs). In addition, incidence and duration of reversible ventricular fibrillation (Rev VF) were lowered by honey 2% (P<0.05). During reperfusion, honey produced significant reduction in the incidences of VT, total and Rev VF, duration and number of VT. The results showed cardioprotective effects of prolonged pre-treatment of rats with honey following myocardial infarction. Maybe, the existence of antioxidants and energy sources (glucose and fructose) in honey composition and improvement of hemodynamic functions may involve in those protective effects.

  18. SALIVARY ANTIMICROBIAL PROTEIN RESPONSE TO PROLONGED RUNNING

    PubMed Central

    Kuennen, M.; Gourley, C.; Schneider, S.; Dokladny, K.; Moseley, P.

    2013-01-01

    Introduction Prolonged exercise may compromise immunity through a reduction of salivary antimicrobial proteins (AMPs). Salivary IgA (IgA) has been extensively studied, but little is known about the effect of acute, prolonged exercise on AMPs including lysozyme (Lys) and lactoferrin (Lac). Objective To determine the effect of a 50-km trail race on salivary cortisol (Cort), IgA, Lys, and Lac. Methods 14 subjects: (6 females, 8 males) completed a 50km ultramarathon. Saliva was collected pre, immediately after (post) and 1.5 hrs post race (+1.5). Results Lac concentration was higher at +1.5 hrs post race compared to post exercise (p < 0.05). Lys was unaffected by the race (p > 0.05). IgA concentration, secretion rate, and IgA/Osm were lower +1.5 hrs post compared to pre race (p < 0.05). Cort concentration was higher at post compared to +1.5 (p < 0.05), but was unaltered from pre race levels. Subjects finished in 7.81±1.2 hrs. Saliva flow rate did not differ between time points. Saliva Osm increased at post (p < 0.05) compared to pre race. Conclusions The intensity could have been too low to alter Lys and Lac secretion rates and thus, may not be as sensitive as IgA to changes in response to prolonged running. Results expand our understanding of the mucosal immune system and may have implications for predicting illness after prolonged running. PMID:24744458

  19. Prolonging life: legal, ethical, and social dilemmas.

    PubMed

    Paulson, Steve; Comfort, Christopher P; Lee, Barbara Coombs; Shemie, Sam; Solomon, Mildred Z

    2014-11-01

    The ability of modern medicine to prolong life has raised a variety of difficult legal, ethical, and social issues on which reasonable minds can differ. Among these are the morality of euthanasia in cases of deep coma or irreversible injury, as well as the Dead Donor Rule with respect to organ harvesting and transplants. As science continues to refine and develop lifesaving technologies, questions remain as to how much medical effort and financial resources should be expended to prolong the lives of patients suspended between life and death. At what point should death be considered irreversible? What criteria should be used to determine when to withhold or withdraw life-prolonging treatments in cases of severe brain damage and terminal illness? To explore these complex dilemmas, Steve Paulson, executive producer and host of To the Best of Our Knowledge, moderated a discussion panel. Pediatrician Sam Shemie, hospice medical director Christopher P. Comfort, bioethicist Mildred Z. Solomon, and attorney Barbara Coombs Lee examined the underlying assumptions and considerations that ultimately shape individual and societal decisions surrounding these issues. The following is an edited transcript of the discussion that occurred November 12, 2013, 7:00-8:30 PM, at the New York Academy of Sciences in New York City.

  20. Prolonged blood circulation of methotrexate by modulation of liposomal composition.

    PubMed

    Hong, M S; Lim, S J; Lee, M K; Kim, Y B; Kim, C K

    2001-01-01

    Prolonged circulation by liposomal incorporation has been shown to enhance the therapeutic efficacy of drugs in many cases. The purpose of this study was to investigate whether the prolonged circulation of methotrexate (MTX) can be achieved by modulating the liposomal compositions. Various compositions of liposomes were prepared with 2:1 of phosphatidylcholine (PC) and cholesterol (CH) with or without distearoylphosphatidyl-ethanolamine-N-poly(ethyleneglycol) 2000 (DSPE-PEG). The MTX encapsulation efficiency depended on the type of PC used. It also appeared to increase by inclusion of DSPE-PEG. The size of liposomes decreased by the inclusion of DSPE-PEG. The inclusion of DSPE-PEG lowered the plasma-induced release of MTX from EggPC/CH and DPPC/CH liposomes, suggesting its enhancement effect on the liposomal stability. After intravenous injection to rats, the pharmacokinetics and biodistribution of MTX were significantly changed by liposomal incorporation and also by the composition of liposomes. The total body clearance of MTX incorporated in EggPC/CH, DPPC/CH, EggPC/CH/DSPE-PEG, and DPPC/CH/DSPE-PEG liposomes decreased 4.4-, 14.9-, 24.5-, and 53.1-fold, compared with that of free MTX. The ratio of MTX concentration in blood to liver and spleen after injection of DPPC/CH, EggPC/CH/DSPE-PEG, and DPPC/CH/DSPE-PEG liposomes was 5.4-, 8.5-, and 13.5-fold higher than that of EggPC/CH liposomes. Furthermore, the accumulation of MTX in the kidney, one of the organs in which MTX exhibits its toxicity, was significantly lowered by liposomal incorporation, especially by DSPE-PEG-containing liposomes. Taken together, DPPC/CH/DSPE-PEG liposomes most effectively prolonged the blood circulation, and reduced hepatosplenic and kidney uptake of MTX. DPPC/CH/DSPE-PEG liposomes may have potential as an efficient delivery system for MTX.

  1. Fetal brain hypometabolism during prolonged hypoxaemia in the llama.

    PubMed

    Ebensperger, Germán; Ebensperger, Renato; Herrera, Emilio A; Riquelme, Raquel A; Sanhueza, Emilia M; Lesage, Florian; Marengo, Juan J; Tejo, Rodrigo I; Llanos, Aníbal J; Reyes, Roberto V

    2005-09-15

    In this study we looked for additional evidence to support the hypothesis that fetal llama reacts to hypoxaemia with adaptive brain hypometabolism. We determined fetal llama brain temperature, Na(+) and K(+) channel density and Na(+)-K(+)-ATPase activity. Additionally, we looked to see whether there were signs of cell death in the brain cortex of llama fetuses submitted to prolonged hypoxaemia. Ten fetal llamas were instrumented under general anaesthesia to measure pH, arterial blood gases, mean arterial pressure, heart rate, and brain and core temperatures. Measurements were made 1 h before and every hour during 24 h of hypoxaemia (n = 5), which was imposed by reducing maternal inspired oxygen fraction to reach a fetal arterial partial pressure of oxygen (P(a,O(2))) of about 12 mmHg. A normoxaemic group was the control (n = 5). After 24 h of hypoxaemia, we determined brain cortex Na(+)-K(+)-ATPase activity, ouabain binding, and the expression of NaV1.1, NaV1.2, NaV1.3, NaV1.6, TREK1, TRAAK and K(ATP) channels. The lack of brain cortex damage was assessed as poly ADP-ribose polymerase (PARP) proteolysis. We found a mean decrease of 0.56 degrees C in brain cortex temperature during prolonged hypoxaemia, which was accompanied by a 51% decrease in brain cortex Na(+)-K(+)-ATPase activity, and by a 44% decrease in protein content of NaV1.1, a voltage-gated Na(+) channel. These changes occurred in absence of changes in PARP protein degradation, suggesting that the cell death of the brain was not enhanced in the fetal llama during hypoxaemia. Taken together, these results provide further evidence to support the hypothesis that the fetal llama responds to prolonged hypoxaemia with adaptive brain hypometabolism, partly mediated by decreases in Na(+)-K(+)-ATPase activity and expression of NaV channels.

  2. QTc Prolongation in Patients Acutely Admitted to Hospital for Psychosis and Treated with Second Generation Antipsychotics

    PubMed Central

    Kroken, Rune A.; Løberg, Else-Marie; Jørgensen, Hugo A.

    2013-01-01

    QTc interval prolongation is a side effect of several antipsychotic drugs, with associated risks of torsade de pointes arrhythmias and sudden cardiac death. There is an ongoing debate of whether or not electrocardiogram (ECG) assessments should be mandatory in patients starting antipsychotic drugs. To investigate QTc prolongation in a clinically relevant patient group 171 adult patients acutely admitted to an emergency ward for psychosis were consecutively recruited. ECGs were recorded at baseline and then at discharge or after 6 weeks at the latest (discharge/6 weeks), thus reflecting the acute phase treatment period. The mean QTc interval was 421.1 (30.4) ms at baseline and there was a positive association between the QTc interval and the agitation score whereas the QTc interval was inversely associated with the serum calcium level. A total of 11.6% had abnormally prolonged QTc intervals and another 14.3% had borderline prolongation. At discharge/6 weeks, the corresponding proportions were reduced to 4.2% and 5.3%, respectively. The reduction of the proportion with prolonged QTc intervals reached statistical significance (chi-square exact test: P = 0.046). The finding of about one-quarter of the patients with borderline or prolonged QTc intervals could indicate mandatory ECG recordings in this population. This trial is registered with ClinicalTrials.gov ID: NCT00932529. PMID:24490070

  3. A review of ropinirole prolonged release in Parkinson’s disease

    PubMed Central

    Nashatizadeh, Muhammad M; Lyons, Kelly E; Pahwa, Rajesh

    2009-01-01

    Ropinirole prolonged release is a once-daily, 24-hour formulation of ropinirole, a non-ergot dopamine agonist. It is approved as monotherapy and as an adjunct to levodopa in the treatment of Parkinson’s disease (PD). Several potential advantages of ropinirole prolonged release compared to the immediate release formulation include maintaining more consistent dopaminergic activity with steadier plasma levels, increased tolerability, greater compliance from a simpler once-daily dosing regimen and ease in dose titration. In a randomized, double-blind, non-inferiority, crossover study, ropinirole prolonged release was shown to have comparable efficacy and tolerability to immediate release ropinirole in early PD patients, with significantly greater compliance. Subjects were converted overnight between ropinirole formulations without loss of efficacy and with good tolerability. In a randomized, double-blind, placebo-controlled study in advanced PD, daily “off” time was reduced by an average of 2.1 hours with ropinirole prolonged release compared to 0.4 hours with placebo. Patients on ropinirole prolonged release were also more likely to require less daily levodopa. Ropinirole prolonged release is well tolerated with a similar adverse effect profile to other non-ergot dopamine agonists. The most common adverse effects include dyskinesia, nausea, dizziness, hallucinations, somnolence, abdominal pain or discomfort and orthostatic hypotension. Ropinirole prolonged release is a safe and effective treatment option for both early and advanced PD. This manuscript briefly reviews the current pharmacological treatment options for PD and provides a more detailed review of the currently available data regarding ropinirole prolonged release as a treatment option for PD. PMID:19503779

  4. Mutant models of prolonged life span.

    PubMed

    Mahler, J F

    2001-01-01

    Aging is an important biological process that affects all creatures. For humans, age-related diseases and the question of why we age and die also have tremendous social and philosophical impact. We can therefore expect that models to study mechanisms of the aging process will always attract much interest. Until recently, the mutant model approach to study molecular mechanisms of aging has been limited to lower animals such as yeast, worms, and flies. However, given the current power of genetic technology in mammals, we can expect that phenotypes of prolonged life span will increasingly be seen in mice and subject to evaluation by pathologists. A brief review of current models is presented.

  5. Electrical shock survival after prolonged cardiopulmonary resuscitation.

    PubMed

    Ahmad, Maqsood; Shabbir, Khawar

    2013-07-01

    Electrical shock is typically an untoward exposure of human body to any source of electricity that causes a sufficient current to pass through the skin, muscles or hair causing undesirable effects ranging from simple burns to death. Ventricular fibrillation is believed to be the most common cause of death following electrical shock. The case under discussion is of a young man who survived following electrical shock after prolonged cardiopulmonary resuscitation (CPR), multiple defibrillations and artificial ventilation due to poor respiratory effort. Early start of chest compressions played a vital role in successful CPR.

  6. Survival of soil bacteria during prolonged desiccation.

    NASA Technical Reports Server (NTRS)

    Chen, M.; Alexander, M.

    1973-01-01

    A determination was made of the kinds and numbers of bacteria surviving when two soils were maintained in the laboratory under dry conditions for more than half a year. Certain non-spore-forming bacteria were found to survive in the dry condition for long periods. A higher percentage of drought-tolerant than drought-sensitive bacteria was able to grow at low water activities. When they were grown in media with high salt concentrations, bacteria generally became more tolerant of prolonged drought and they persisted longer. The percent of cells in a bacterial population that remained viable when exposed to drought stress varied with the stage of growth.

  7. Survival without sequelae after prolonged cardiopulmonary resuscitation after electric shock.

    PubMed

    Motawea, Mohamad; Al-Kenany, Al-Sayed; Hosny, Mostafa; Aglan, Omar; Samy, Mohamad; Al-Abd, Mohamed

    2016-03-01

    "Electrical shock is the physiological reaction or injury caused by electric current passing through the human body. It occurs upon contact of a human body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair causing undesirable effects ranging from simple burns to death." Ventricular fibrillation is believed to be the most common cause of death after electrical shock. "The ideal duration of cardiac resuscitation is unknown. Typically prolonged cardiopulmonary resuscitation is associated with poor neurologic outcomes and reduced long term survival. No consensus statement has been made and traditionally efforts are usually terminated after 15-30 minutes." The case under discussion seems worthy of the somewhat detailed description given. It is for a young man who survived after 65 minutes after electrical shock (ES) after prolonged high-quality cardiopulmonary resuscitation (CPR), multiple defibrillations, and artificial ventilation without any sequelae. Early start of adequate chest compressions and close adherence to advanced cardiac life support protocols played a vital role in successful CPR.

  8. Skeletal muscle water and electrolytes following prolonged dehydrating exercise.

    PubMed

    Mora-Rodríguez, R; Fernández-Elías, V E; Hamouti, N; Ortega, J F

    2015-06-01

    We studied if dehydrating exercise would reduce muscle water (H2Omuscle ) and affect muscle electrolyte concentrations. Vastus lateralis muscle biopsies were collected prior, immediately after, and 1 and 4 h after prolonged dehydrating exercise (150 min at 33 ± 1 °C, 25% ± 2% humidity) on nine endurance-trained cyclists (VO2max  = 54.4 ± 1.05 mL/kg/min). Plasma volume (PV) changes and fluid shifts between compartments (Cl(-) method) were measured. Exercise dehydrated subjects 4.7% ± 0.3% of body mass by losing 2.75 ± 0.15 L of water and reducing PV 18.4% ± 1% below pre-exercise values (P < 0.05). Right after exercise H2Omuscle remained at pre-exercise values (i.e., 398 ± 6 mL/100 g dw muscle(-1)) but declined 13% ± 2% (342 ± 12 mL/100 g dw muscle(-1); P < 0.05) after 1 h of supine rest. At that time, PV recovered toward pre-exercise levels. The Cl(-) method corroborated the shift of fluid between extracellular and intracellular compartments. After 4 h of recovery, PV returned to pre-exercise values; however, H2Omuscle remained reduced at the same level. Muscle Na(+) and K(+) increased (P < 0.05) in response to the H2Omuscle reductions. Our findings suggest that active skeletal muscle does not show a net loss of H2O during prolonged dehydrating exercise. However, during the first hour of recovery H2Omuscle decreases seemly to restore PV and thus cardiovascular stability.

  9. Blueberry extract prolongs lifespan of Drosophila melanogaster.

    PubMed

    Peng, Cheng; Zuo, Yuanyuan; Kwan, Kin Ming; Liang, Yintong; Ma, Ka Ying; Chan, Ho Yin Edwin; Huang, Yu; Yu, Hongjian; Chen, Zhen-Yu

    2012-02-01

    Blueberry possesses greater antioxidant capacity than most other fruits and vegetables. The present study investigated the lifespan-prolonging activity of blueberry extracts in fruit flies and explored its underlying mechanism. Results revealed that blueberry extracts at 5mg/ml in diet could significantly extend the mean lifespan of fruit flies by 10%, accompanied by up-regulating gene expression of superoxide dismutase (SOD), catalase (CAT) and Rpn11 and down-regulating Methuselah (MTH) gene. Intensive H(2)O(2) and Paraquat challenge tests showed that lifespan was only extended in Oregon-R wild type flies but not in SOD(n108) or Cat(n1) mutant strains. Chronic Paraquat exposure shortened the maximum survival time from 73 to 35days and decreased the climbing ability by 60% while blueberry extracts at 5mg/ml in diet could significantly increase the survival rate and partially restore the climbing ability with up-regulating SOD, CAT, and Rpn11. Furthermore, gustatory assay demonstrated that those changes were not due to the variation of food intake between the control and the experimental diet containing 5mg/ml blueberry extracts. It was therefore concluded that the lifespan-prolonging activity of blueberry extracts was at least partially associated with its interactions with MTH, Rpn11, and endogenous antioxidant enzymes SOD and CAT.

  10. Topical Drug Formulations for Prolonged Corneal Anesthesia

    PubMed Central

    Wang, Liqiang; Shankarappa, Sahadev A.; Tong, Rong; Ciolino, Joseph B.; Tsui, Jonathan H.; Chiang, Homer H.; Kohane, Daniel S.

    2013-01-01

    Purpose Ocular local anesthetics (OLA’s) currently used in routine clinical practice for corneal anesthesia are short acting and their ability to delay corneal healing makes them unsuitable for long-term use. In this study, we examined the effect on the duration of corneal anesthesia of the site-1 sodium channel blocker tetrodotoxin (TTX), applied with either proparacaine or the chemical permeation enhancer OTAB. The effect of test solutions on corneal healing was also studied. Methods Solutions of TTX, proparacaine, and OTAB, singly or in combination were applied topically to the rat cornea. The blink response, an indirect measure of corneal sensitivity, was recorded using a Cochet-Bonnet esthesiometer, and the duration of corneal anesthesia calculated. The effect of test compounds on the rate of corneal epithelialization was studied in vivo following corneal debridement. Results Combination of TTX and proparacaine resulted in corneal anesthesia that was 8–10 times longer in duration than that from either drug administered alone, while OTAB did not prolong anesthesia. The rate of corneal healing was moderately delayed following co-administration of TTX and proparacaine. Conclusion Co-administration of TTX and proparacaine significantly prolonged corneal anesthesia but in view of delayed corneal re-epithelialization, caution is suggested in use of the combination. PMID:23615270

  11. Review and Outcome of Prolonged Cardiopulmonary Resuscitation

    PubMed Central

    Youness, Houssein; Al Halabi, Tarek; Hussein, Hussein; Awab, Ahmed; Jones, Kellie; Keddissi, Jean

    2016-01-01

    The maximal duration of cardiopulmonary resuscitation (CPR) is unknown. We report a case of prolonged CPR. We have then reviewed all published cases with CPR duration equal to or more than 20 minutes. The objective was to determine the survival rate, the neurological outcome, and the characteristics of the survivors. Measurements and Main Results. The CPR data for 82 patients was reviewed. The median duration of CPR was 75 minutes. Patients mean age was 43 ± 21 years with no significant comorbidities. The main causes of the cardiac arrests were myocardial infarction (29%), hypothermia (21%), and pulmonary emboli (12%). 74% of the arrests were witnessed, with a mean latency to CPR of 2 ± 6 minutes and good quality chest compression provided in 96% of the cases. Adjunct therapy included extracorporeal membrane oxygenation (18%), thrombolysis (15.8%), and rewarming for hypothermia (19.5%). 83% were alive at 1 year, with full neurological recovery reported in 63 patients. Conclusion. Patients undergoing prolonged CPR can survive with good outcome. Young age, myocardial infarction, and potentially reversible causes of cardiac arrest such as hypothermia and pulmonary emboli predict a favorable result, especially when the arrest is witnessed and followed by prompt and good resuscitative efforts. PMID:26885387

  12. [Left ventricular dyssynchrony in prolonged septal stimulation].

    PubMed

    Ferrando-Castagnetto, Federico; Ricca-Mallada, Roberto; Vidal, Alejandro; Martínez, Fabián; Ferrando, Rodolfo

    2016-01-01

    Pacemaker stimulation is associated with unpredictable severe cardiac events. We evaluated left ventricular mechanical dyssynchrony (LVMD) during prolonged septal right ventricular pacing. We performed 99mTc-MIBI gated-SPECT and phase analysis in 6 patients with pacemakers implanted at least one year before scintigraphy due to advanced atrioventricular block. Using V-Sync of Emory Cardiac Toolbox we obtained phase bandwidth (PBW) and standard deviation (PSD) from rest phase histogram. Clinical variables, QRS duration, rate and mode of pacing in septal right ventricle wall, chamber diameters, presence and extension of myocardial scar and ischemia and rest LVEF were recorded. Prolonged septal endocardial pacing is associated with marked LVMD, even when systolic function was preserved. More severe dyssynchrony was found in patients with impaired LVEF, higher left ventricle diameters, extensive infarct or severe ischemia than in patients with preserved LVEF (PBW: 177.3o vs. 88.3o; PSD: 53.1o vs. 33.8o). In the patients with ischemic heart disease and pacemaker, gated-SPECT phase analysis is a valid and potentially useful technique to evaluate LMVD associated with myocardial scar and to decide the upgrading to biventricular pacing mode.

  13. Does prolonged breastfeeding adversely affect a child's nutritional status?

    PubMed

    Brakohiapa, L A; Yartey, J; Bille, A; Harrison, E; Quansah, E; Armar, M A; Kishi, K; Yamamoto, S

    1988-08-20

    In 202 children who visited a children's hospital in the city of Accra, Ghana, breastfeeding beyond the age of 19 months was found to be associated with malnutrition. The effect of weaning on food intake was then studied in 15 breastfed malnourished children in a rural community. Before weaning (complete cessation of breast-feeding) protein and energy intakes of all the malnourished children were about half those of 5 normal children. 10 of the malnourished children were weaned, and their intakes rose to the levels of the normal children; the 5 who continued breastfeeding maintained their low intakes. These results indicate that prolonged breastfeeding can reduce total food intake and thus predispose to malnutrition. They also suggest that in Ghana and other developing countries the proper weaning age may be about 18 months.

  14. Impact of prolonged leucine supplementation on protein synthesis and lean growth in neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most low-birth weight infants experience extrauterine growth failure due to reduced nutrient intake as a result of feeding intolerance. The objective of this study was to determine whether prolonged enteral leucine supplementation improves lean growth in neonatal pigs fed a restricted protein diet. ...

  15. Drug-induced QT interval prolongation: mechanisms and clinical management

    PubMed Central

    Nachimuthu, Senthil; Assar, Manish D.

    2012-01-01

    The prolonged QT interval is both widely seen and associated with the potentially deadly rhythm, Torsades de Pointes (TdP). While it can occur spontaneously in the congenital form, there is a wide array of drugs that have been implicated in the prolongation of the QT interval. Some of these drugs have either been restricted or withdrawn from the market due to the increased incidence of fatal polymorphic ventricular tachycardia. The list of drugs that cause QT prolongation continues to grow, and an updated list of specific drugs that prolong the QT interval can be found at www.qtdrugs.org. This review focuses on the mechanism of drug-induced QT prolongation, risk factors for TdP, culprit drugs, prevention and monitoring of prolonged drug-induced QT prolongation and treatment strategies. PMID:25083239

  16. Factors associated with prolonged length of stay in older patients

    PubMed Central

    Toh, Hui Jin; Lim, Zhen Yu; Yap, Philip; Tang, Terence

    2017-01-01

    INTRODUCTION Prolonged stay in acute hospitals increases the risk of hospital-acquired infections in older patients, and disrupts patient flow and access to care due to bed shortages. We aimed to investigate the factors associated with prolonged length of stay (pLOS) among older patients (aged ≥ 78 years) in a tertiary hospital, to identify the potentially modifiable risk factors that could direct interventions to reduce length of stay (LOS). METHODS During a three-month period from January 2013 to March 2013, we identified 72 patients with pLOS (LOS ≥ 21 days) and compared their demographic and clinical variables with that of 281 randomly selected control patients (LOS < 21 days) using univariate and multivariate logistic regression analyses. RESULTS The mean age of the patients was 85.30 ± 5.34 years; 54% of them were female and 72% were of Chinese ethnicity. Logistic regression revealed the following significant factors for increased LOS: discharge to intermediate and long-term care services (odds ratio [OR] 9.22, 95% confidence interval [CI] 3.56–23.89; p < 0.001); increased severity of illness (OR 2.41, 95% CI 1.12–5.21; p = 0.025); and presence of caregiver stress (OR 3.85, 95% CI 1.67–8.91; p = 0.002). CONCLUSION Presence of caregiver stress and nursing home placement are potential modifiable risk factors of pLOS among older patients. Early identification and management of caregiver stress, as well as expediting discharge planning, may help to reduce the length of stay for this cohort. PMID:27609507

  17. Dengue haemorrhagic fever with unusual prolonged thrombocytopaenia.

    PubMed

    Kamil, S M; Mohamad, N H; Narazah, M Y; Khan, F A

    2006-04-01

    We describe a case of dengue haemorrhagic fever with prolonged thrombocytopaenia. A 22-year-old Malay man with no prior illness presented with a history of fever and generalised macular rash of four days duration. Initial work-up suggested the diagnosis of dengue haemorrhagic fever based on thrombocytopaenia and positive dengue serology. Patient recovered from acute illness by day ten, and was discharged from the hospital with improving platelet count. He was then noted to have declining platelet count on follow-up and required another hospital admission on day 19 of his illness because of declining platelet count. The patient remained hospitalised till day 44 of his illness and managed with repeated platelet transfusion and supportive care till he recovered spontaneously.

  18. Bilateral Scapulohumeral Ankylosis after Prolonged Mechanical Ventilation

    PubMed Central

    Schreinemakers, J. Rieneke; van Noort, Arthur; Rademakers, Maarten V.

    2016-01-01

    This case demonstrates a rarely reported bilateral scapulohumeral bony ankylosis. A young woman developed extensive heterotopic ossifications (HOs) in both shoulder joints after being mechanically ventilated for several months at the intensive care unit in a comatose status. She presented with a severe movement restriction of both shoulder joints. Surgical resection of the bony bridges was performed in 2 separate sessions with a significant improvement of shoulder function afterwards. No postoperative complications, pain, or recurrence of HOs were noted at 1-year follow-up. Mechanical ventilation, immobilization, neuromuscular blockage, and prolonged sedation are known risk factors for the development of HOs in the shoulder joints. Relatively early surgical resection of the HOs can be performed safely in contrary to earlier belief. Afterwards, nonsteroidal anti-inflammatory drugs and/or radiation therapy can be possible treatment modalities to prevent recurrence of HOs. PMID:27583120

  19. Risperidone prolongs cardiac action potential through reduction of K+ currents in rabbit myocytes.

    PubMed

    Gluais, Pascale; Bastide, Michèle; Caron, Jacques; Adamantidis, Monique

    2002-05-31

    Prolongation of QT interval by antipsychotic drugs is an unwanted side effect that may lead to ventricular arrhythmias. The antipsychotic agent risperidone has been shown to cause QT prolongation, especially in case of overdosage. We investigated risperidone effects on action potentials recorded from rabbit Purkinje fibers and ventricular myocardium and on potassium currents recorded from atrial and ventricular rabbit isolated myocytes. The results showed that (1) risperidone (0.1-3 microM) exerted potent lengthening effects on action potential duration in both tissues with higher potency in Purkinje fibers and caused the development of early afterdepolarizations at low stimulation rate; (2) risperidone (0.03-0.3 microM) reduced significantly the current density of the delayed rectifier current and at 30 microM decreased the transient outward and the inward rectifier currents. This study might explain QT prolongation observed in some patients treated with risperidone and gives enlightenment on the risk of cardiac adverse events.

  20. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, Mark W.; Yoshida, Tatsuro

    1998-01-01

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4.degree. C. storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4.degree. C. for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials.

  1. Prolonged cold storage of red blood cells by oxygen removal and additive usage

    DOEpatents

    Bitensky, M.W.; Yoshida, Tatsuro

    1998-08-04

    Prolonged cold storage of red blood cells by oxygen removal and additive usage. A cost-effective, 4 C storage procedure that preserves red cell quality and prolongs post-transfusion in vivo survival is described. The improved in vivo survival and the preservation of adenosine triphosphate levels, along with reduction in hemolysis and membrane vesicle production of red blood cells stored at 4 C for prolonged periods of time, is achieved by reducing the oxygen level therein at the time of storage; in particular, by flushing the cells with an inert gas, and storing them in an aqueous solution which includes adenine, dextrose, mannitol, citrate ion, and dihydrogen phosphate ion, but no sodium chloride, in an oxygen-permeable container which is located in an oxygen-free environment containing oxygen-scavenging materials. 8 figs.

  2. Capacitance-Based Frequency Adjustment of Micro Piezoelectric Vibration Generator

    PubMed Central

    Mao, Xinhua; He, Qing; Li, Hong; Chu, Dongliang

    2014-01-01

    Micro piezoelectric vibration generator has a wide application in the field of microelectronics. Its natural frequency is unchanged after being manufactured. However, resonance cannot occur when the natural frequencies of a piezoelectric generator and the source of vibration frequency are not consistent. Output voltage of the piezoelectric generator will sharply decline. It cannot normally supply power for electronic devices. In order to make the natural frequency of the generator approach the frequency of vibration source, the capacitance FM technology is adopted in this paper. Different capacitance FM schemes are designed by different locations of the adjustment layer. The corresponding capacitance FM models have been established. Characteristic and effect of the capacitance FM have been simulated by the FM model. Experimental results show that the natural frequency of the generator could vary from 46.5 Hz to 42.4 Hz when the bypass capacitance value increases from 0 nF to 30 nF. The natural frequency of a piezoelectric vibration generator could be continuously adjusted by this method. PMID:25133237

  3. Capacitance-based frequency adjustment of micro piezoelectric vibration generator.

    PubMed

    Mao, Xinhua; He, Qing; Li, Hong; Chu, Dongliang

    2014-01-01

    Micro piezoelectric vibration generator has a wide application in the field of microelectronics. Its natural frequency is unchanged after being manufactured. However, resonance cannot occur when the natural frequencies of a piezoelectric generator and the source of vibration frequency are not consistent. Output voltage of the piezoelectric generator will sharply decline. It cannot normally supply power for electronic devices. In order to make the natural frequency of the generator approach the frequency of vibration source, the capacitance FM technology is adopted in this paper. Different capacitance FM schemes are designed by different locations of the adjustment layer. The corresponding capacitance FM models have been established. Characteristic and effect of the capacitance FM have been simulated by the FM model. Experimental results show that the natural frequency of the generator could vary from 46.5 Hz to 42.4 Hz when the bypass capacitance value increases from 0 nF to 30 nF. The natural frequency of a piezoelectric vibration generator could be continuously adjusted by this method.

  4. Predicting Prolonged Stay in the ICU Attributable to Bleeding in Patients Offered Plasma Transfusion

    PubMed Central

    Ngufor, Che; Murphree, Dennis; Upadhyaya, Sudhi; Madde, Nageswar; Pathak, Jyotishman; Carter, Rickey; Kor, Daryl

    2016-01-01

    In blood transfusion studies, plasma transfusion (PPT) and bleeding are known to be associated with risk of prolonged ICU length of stay (ICU-LOS). However, as patients can show significant heterogeneity in response to a treatment, there might exists subgroups with differential effects. The existence and characteristics of these subpopulations in blood transfusion has not been well-studied. Further, the impact of bleeding in patients offered PPT on prolonged ICU-LOS is not known. This study presents a causal and predictive framework to examine these problems. The two-step approach first estimates the effect of bleeding in PPT patients on prolonged ICU-LOS and then estimates risks of bleeding and prolonged ICU-LOS. The framework integrates a classification model for risks prediction and a regression model to predict actual LOS. Results showed that the effect of bleeding in PPT patients significantly increases risk of prolonged ICU-LOS (55%, p=0.00) while no bleeding significantly reduces ICU-LOS (4%, p=0.046). PMID:28269892

  5. Fetal brain hypometabolism during prolonged hypoxaemia in the llama

    PubMed Central

    Ebensperger, Germán; Ebensperger, Renato; Herrera, Emilio A; Riquelme, Raquel A; Sanhueza, Emilia M; Lesage, Florian; Marengo, Juan J; Tejo, Rodrigo I; Llanos, Aníbal J; Reyes, Roberto V

    2005-01-01

    In this study we looked for additional evidence to support the hypothesis that fetal llama reacts to hypoxaemia with adaptive brain hypometabolism. We determined fetal llama brain temperature, Na+ and K+ channel density and Na+–K+-ATPase activity. Additionally, we looked to see whether there were signs of cell death in the brain cortex of llama fetuses submitted to prolonged hypoxaemia. Ten fetal llamas were instrumented under general anaesthesia to measure pH, arterial blood gases, mean arterial pressure, heart rate, and brain and core temperatures. Measurements were made 1 h before and every hour during 24 h of hypoxaemia (n = 5), which was imposed by reducing maternal inspired oxygen fraction to reach a fetal arterial partial pressure of oxygen (Pa,O2) of about 12 mmHg. A normoxaemic group was the control (n = 5). After 24 h of hypoxaemia, we determined brain cortex Na+–K+-ATPase activity, ouabain binding, and the expression of NaV1.1, NaV1.2, NaV1.3, NaV1.6, TREK1, TRAAK and KATP channels. The lack of brain cortex damage was assessed as poly ADP-ribose polymerase (PARP) proteolysis. We found a mean decrease of 0.56°C in brain cortex temperature during prolonged hypoxaemia, which was accompanied by a 51% decrease in brain cortex Na+–K+-ATPase activity, and by a 44% decrease in protein content of NaV1.1, a voltage-gated Na+ channel. These changes occurred in absence of changes in PARP protein degradation, suggesting that the cell death of the brain was not enhanced in the fetal llama during hypoxaemia. Taken together, these results provide further evidence to support the hypothesis that the fetal llama responds to prolonged hypoxaemia with adaptive brain hypometabolism, partly mediated by decreases in Na+–K+-ATPase activity and expression of NaV channels. PMID:16037083

  6. Prolonged Inner Retinal Photoreception Depends on the Visual Retinoid Cycle

    PubMed Central

    Zhao, Xiwu; Pack, Weston; Khan, Naheed W.

    2016-01-01

    In addition to rods and cones, mammals have inner retinal photoreceptors called intrinsically photosensitive retinal ganglion cells (ipRGCs), which use the photopigment melanopsin and mediate nonimage-forming visual responses, such as pupil reflexes and circadian entrainment. After photic activation, photopigments must be reverted to their dark state to be light-sensitive again. For rods and to some extent cones, photopigment regeneration depends on the retinoid cycle in the adjacent retinal pigment epithelium (RPE). By contrast, ipRGCs are far from the RPE, and previous work suggests that melanopsin is capable of light-dependent self-regeneration. Here, we used in vitro ipRGC recording and in vivo pupillometry to show that the RPE is required for normal melanopsin-based responses to prolonged light, especially at high stimulus intensities. Melanopsin-based photoresponses of rat ipRGCs were remarkably sustained when a functional RPE was attached to the retina, but became far more transient if the RPE was removed, or if the retinoid cycle was inhibited, or when Müller glia were poisoned. Similarly, retinoid cycle inhibition markedly reduced the steady-state amplitude of melanopsin-driven pupil reflexes in both mice and rats. However, melanopsin photoresponses in RPE-separated rat retinas became more sustained in the presence of an 11-cis-retinal analog. In conclusion, during prolonged illumination, melanopsin regeneration depends partly on 11-cis-retinal from the RPE, possibly imported via Müller cells. Implications for RPE-related eye diseases and the acne drug isotretinoin (a retinoid cycle inhibitor) are discussed. SIGNIFICANCE STATEMENT Intrinsically photosensitive retinal ganglion cells (ipRGCs) contain the photopigment melanopsin and drive subconscious physiological responses to light, e.g., pupillary constriction and neuroendocrine regulation. In darkness, each photopigment molecule in ipRGCs, as well as rod/cone photoreceptors, contains 11-cis-retinal (a

  7. Thrombolytic-Enhanced Extracorporeal Cardiopulmonary Resuscitation After Prolonged Cardiac Arrest

    PubMed Central

    Spinelli, Elena; Davis, Ryan P.; Ren, Xiaodan; Sheth, Parth S.; Tooley, Trevor R.; Iyengar, Amit; Sowell, Brandon; Owens, Gabe E.; Bocks, Martin L.; Jacobs, Teresa L.; Yang, Lynda J.; Stacey, William C.; Bartlett, Robert H.; Rojas-Peña, Alvaro; Neumar, Robert W.

    2016-01-01

    Objective To investigate the effects of the combination of extracorporeal cardiopulmonary resuscitation (ECPR) and thrombolytic therapy on the recovery of vital organ function after prolonged cardiac arrest. Design Laboratory investigation Setting University Laboratory Subjects Pigs Interventions Animals underwent 30-minute untreated ventricular fibrillation cardiac arrest followed by extracorporeal cardiopulmonary resuscitation (ECPR) for 6 hours. Animals were allocated into two experimental groups: t-ECPR, which received Streptokinase 1 MU and c-ECPR which did not receive Streptokinase. In both groups the resuscitation protocol included the following physiologic targets: mean arterial pressure (MAP) > 70 mmHg, Cerebral perfusion pressure (CerPP) > 50 mmHg, PaO2 150 ± 50 mmHg, PaCO2 40 ± 5 mmHg and core temperature 33 ± 1 °C. Defibrillation was attempted after 30 minutes of ECPR. Measurements and Main Results A cardiac resuscitability score was assessed on the basis of: success of defibrillation; return of spontaneous heart beat; weanability form ECPR; and left ventricular systolic function after weaning. The addition of thrombolytic to ECPR significantly improved cardiac resuscitability (3.7 ± 1.6 in t-ECPR vs 1.0 ± 1.5 in c-ECPR). Arterial lactate clearance was higher in t-ECPR than in c-ECPR (40 ± 15% VS 18 ± 21 %). At the end of the experiment, the intracranial pressure was significantly higher in c-ECPR than in t-ECPR. Recovery of brain electrical activity, as assessed by quantitative analysis of EEG signal, and ischemic neuronal injury on histopathologic examination did not differ between groups. Animals in t-ECPR group did not have increased bleeding complications, including intracerebral hemorrhages. Conclusions In a porcine model of prolonged cardiac arrest, thrombolytic-enhanced ECPR improved cardiac resuscitability and reduced brain edema, without increasing bleeding complications. However, early EEG recovery and ischemic neuronal injury were

  8. Grace's story: prolonged incestuous abuse from childhood into adulthood.

    PubMed

    Salter, Michael

    2013-02-01

    Some sexually abused women in mental health settings are reporting prolonged incest and yet little is known about the circumstances that enable fathers to sexually abuse their daughters over a period of decades. This article draws from the life history of Grace, a woman who survived prolonged incest, in order to document and analyze the interplay of familial, social, and political factors that entrap girls and women within prolonged incestuous abuse.

  9. Prolonging life and allowing death: infants.

    PubMed

    Campbell, A G; McHaffie, H E

    1995-12-01

    Dilemmas about resuscitation and life-prolonging treatment for severely compromised infants have become increasingly complex as skills in neonatal care have developed. Quality of life and resource issues necessarily influence management. Our Institute of Medical Ethics working party, on whose behalf this paper is written, recognises that the ultimate responsibility for the final decision rests with the doctor in clinical charge of the infant. However, we advocate a team approach to decision-making, emphasising the important role of parents and nurses in the process. Assessing the relative burdens and benefits can be troubling, but doctors and parents need to retain a measure of discretion; legislation which would determine action in all cases is inappropriate. Caution should be exercised in involving committees in decision-making and, where they exist, their remit should remain to advise rather than to decide. Support for families who bear the consequences of their decisions is often inadequate, and facilitating access to such services is part of the wider responsibilities of the intensive care team. The authors believe that allowing death by withholding or withdrawing treatment is legitimate, where those closely involved in the care of the infant together deem the burdens to be unacceptable without compensating benefits for the infant. As part of the process accurate and careful recording is essential.

  10. Pulmonary diffusion limitation after prolonged strenuous exercise.

    PubMed

    Manier, G; Moinard, J; Téchoueyres, P; Varène, N; Guénard, H

    1991-02-01

    To determine the effect of strenuous prolonged exercise on alveolo-capillary membrane diffusing capacity, 11 marathon runners aged 37 +/- 7 years (mean +/- SD) were studied before and during early recovery (28 +/- 14 min) from a marathon race. Lung capillary blood volume (Vc) and the alveolo-capillary diffusing capacity (Dm) were determined in a one-step maneuver by simultaneous measurements of CO and NO lung transfer (DLCO and DLNO, respectively) using the single breath, breath-holding method. After the race, both DLCO and DLNO were significantly decreased in all subjects (-10.9 +/- 4.8%, P less than 10(-4) and -29.0 +/- 11.1%, P less than 10(-4), respectively). The mean value of the derived DmCO decreased by -29.3 +/- 11.1%, whereas Vc had not entirely returned to control resting value. Although these results do not indicate the detailed mechanism involved, interstitial lung fluid was suspected to accumulate, particularly in alveoli, during the race. We concluded that the high overall work load and the extended duration of the exercise both contributed to a transient change in the structure of the alveolo-capillary membrane thereby affecting the diffusing capacity of the alveolo-capillary membrane.

  11. Prolonged cholestasis and ductopenia associated with tenoxicam.

    PubMed

    Trak-Smayra, Viviane; Cazals-Hatem, Dominique; Asselah, Tarik; Duchatelle, Veronique; Degott, Claude

    2003-07-01

    Cholestatic liver diseases leading to progressive destruction of intra-hepatic bile ducts and ductopenia encompass multiple etiologies. Pathophysiology and natural history of drug-induced cholangiopathies remain unclear. We report a case of prolonged ductopenia attributed to Tenoxicam (Tilcotil o--a non-steroidal anti-inflammatory drug of the oxicam family) ingested at therapeutic dose. A 36 year-old male patient was admitted for jaundice and Lyell syndrome starting 1 week after the ingestion of Tenoxicam. Liver biopsy showed cholestasis, non-suppurative cholangitis and polymorphous inflammatory infiltrate of the portal tracts (round cells, macrophages an eosinophils). Treatment with ursodesoxycholic acid and cholestyramine was instituted and the patient was asymptomatic 1 year after. Three years later mild biological cholestasis persisted and ductopenia was evidenced on liver biopsy. In this report we found that: (1) The toxicity of tenoxicam was probably mediated by an immunoallergic mechanism (Lyell syndrome and eosinophils on histology); (2) ductopenia was secondary to inflammatory cholangitis. Factors responsible for this chronic evolution are still unknown (genetic predisposition, vascular factors, etc.); and (3) the presence of ductopenia contrasted with the "clinical recovery" of the disease suggesting accessory bile drainage by cholangioles or partial reconstruction of the biliary tree.

  12. Persistent telomere cohesion triggers a prolonged anaphase.

    PubMed

    Kim, Mi Kyung; Smith, Susan

    2014-01-01

    Telomeres use distinct mechanisms (not used by arms or centromeres) to mediate cohesion between sister chromatids. However, the motivation for a specialized mechanism at telomeres is not well understood. Here we show, using fluorescence in situ hybridization and live-cell imaging, that persistent sister chromatid cohesion at telomeres triggers a prolonged anaphase in normal human cells and cancer cells. Excess cohesion at telomeres can be induced by inhibition of tankyrase 1, a poly(ADP-ribose) polymerase that is required for resolution of telomere cohesion, or by overexpression of proteins required to establish telomere cohesion, the shelterin subunit TIN2 and the cohesin subunit SA1. Regardless of the method of induction, excess cohesion at telomeres in mitosis prevents a robust and efficient anaphase. SA1- or TIN2-induced excess cohesion and anaphase delay can be rescued by overexpression of tankyrase 1. Moreover, we show that primary fibroblasts, which accumulate excess telomere cohesion at mitosis naturally during replicative aging, undergo a similar delay in anaphase progression that can also be rescued by overexpression of tankyrase 1. Our study demonstrates that there are opposing forces that regulate telomere cohesion. The observation that cells respond to unresolved telomere cohesion by delaying (but not completely disrupting) anaphase progression suggests a mechanism for tolerating excess cohesion and maintaining telomere integrity. This attempt to deal with telomere damage may be ultimately futile for aging fibroblasts but useful for cancer cells.

  13. Haploinsufficiency of Akt1 Prolongs the Lifespan of Mice

    PubMed Central

    Nojima, Aika; Yamashita, Masakatsu; Yoshida, Yohko; Shimizu, Ippei; Ichimiya, Harumi; Kamimura, Naomi; Kobayashi, Yoshio; Ohta, Shigeo; Ishii, Naoaki; Minamino, Tohru

    2013-01-01

    There is increasing evidence that nutrient-sensing machinery is critically involved in the regulation of aging. The insulin/insulin-like growth factor-1 signaling pathway is the best-characterized pathway with an influence on longevity in a variety of organisms, ranging from yeast to rodents. Reduced expression of the receptor for this pathway has been reported to prolong the lifespan; however, the underlying mechanisms are largely unknown. Here we show that haploinsufficiency of Akt1 leads to an increase of the lifespan in mice. Akt1+/– mice had a lower body weight than their littermates with less fat mass and normal glucose metabolism. Ribosomal biogenesis and the mitochondrial DNA content were significantly reduced in these mice, along with a decrease of oxidative stress. Consistent with the results obtained in mice, inhibition of Akt-1 promoted longevity in nematodes (Caenorhabditis elegans), whereas activation of Akt-1 shortened the lifespan. Inhibition of Akt-1 led to a decrease of ribosomal gene expression and the mitochondrial DNA content in both human cells and nematodes. Moreover, deletion of ribosomal gene expression resulted in a decrease of the mitochondrial DNA content and normalized the lifespan shortened by Akt-1 activation in nematodes. These results suggest that an increase of mitochondrial amount and energy expenditure associated with enhanced protein synthesis accelerates both aging and the onset of age-associated diseases. PMID:23935948

  14. Fatigue associated with prolonged graded running.

    PubMed

    Giandolini, Marlene; Vernillo, Gianluca; Samozino, Pierre; Horvais, Nicolas; Edwards, W Brent; Morin, Jean-Benoît; Millet, Guillaume Y

    2016-10-01

    Scientific experiments on running mainly consider level running. However, the magnitude and etiology of fatigue depend on the exercise under consideration, particularly the predominant type of contraction, which differs between level, uphill, and downhill running. The purpose of this review is to comprehensively summarize the neurophysiological and biomechanical changes due to fatigue in graded running. When comparing prolonged hilly running (i.e., a combination of uphill and downhill running) to level running, it is found that (1) the general shape of the neuromuscular fatigue-exercise duration curve as well as the etiology of fatigue in knee extensor and plantar flexor muscles are similar and (2) the biomechanical consequences are also relatively comparable, suggesting that duration rather than elevation changes affects neuromuscular function and running patterns. However, 'pure' uphill or downhill running has several fatigue-related intrinsic features compared with the level running. Downhill running induces severe lower limb tissue damage, indirectly evidenced by massive increases in plasma creatine kinase/myoglobin concentration or inflammatory markers. In addition, low-frequency fatigue (i.e., excitation-contraction coupling failure) is systematically observed after downhill running, although it has also been found in high-intensity uphill running for different reasons. Indeed, low-frequency fatigue in downhill running is attributed to mechanical stress at the interface sarcoplasmic reticulum/T-tubule, while the inorganic phosphate accumulation probably plays a central role in intense uphill running. Other fatigue-related specificities of graded running such as strategies to minimize the deleterious effects of downhill running on muscle function, the difference of energy cost versus heat storage or muscle activity changes in downhill, level, and uphill running are also discussed.

  15. Exceptionally prolonged tooth formation in elasmosaurid plesiosaurians

    PubMed Central

    Kear, Benjamin P.; Larsson, Dennis; Lindgren, Johan; Kundrát, Martin

    2017-01-01

    Elasmosaurid plesiosaurians were globally prolific marine reptiles that dominated the Mesozoic seas for over 70 million years. Their iconic body-plan incorporated an exceedingly long neck and small skull equipped with prominent intermeshing ‘fangs’. How this bizarre dental apparatus was employed in feeding is uncertain, but fossilized gut contents indicate a diverse diet of small pelagic vertebrates, cephalopods and epifaunal benthos. Here we report the first plesiosaurian tooth formation rates as a mechanism for servicing the functional dentition. Multiple dentine thin sections were taken through isolated elasmosaurid teeth from the Upper Cretaceous of Sweden. These specimens revealed an average of 950 daily incremental lines of von Ebner, and infer a remarkably protracted tooth formation cycle of about 2–3 years–other polyphyodont amniotes normally take ~1–2 years to form their teeth. Such delayed odontogenesis might reflect differences in crown length and function within an originally uneven tooth array. Indeed, slower replacement periodicity has been found to distinguish larger caniniform teeth in macrophagous pliosaurid plesiosaurians. However, the archetypal sauropterygian dental replacement system likely also imposed constraints via segregation of the developing tooth germs within discrete bony crypts; these partly resorbed to allow maturation of the replacement teeth within the primary alveoli after displacement of the functional crowns. Prolonged dental formation has otherwise been linked to tooth robustness and adaption for vigorous food processing. Conversely, elasmosaurids possessed narrow crowns with an elongate profile that denotes structural fragility. Their apparent predilection for easily subdued prey could thus have minimized this potential for damage, and was perhaps coupled with selective feeding strategies that ecologically optimized elasmosaurids towards more delicate middle trophic level aquatic predation. PMID:28241059

  16. Utilization of extracorporeal membrane oxygenation alleviates intestinal ischemia-reperfusion injury in prolonged hemorrhagic shock animal model.

    PubMed

    Zhao, Liang; Luo, Lin; Chen, Jinjin; Xiao, Juan; Jia, Weikun; Xiao, Yingbin

    2014-12-01

    Intestinal ischemia-reperfusion injury is one of the main factors leading to multiple organ failure after resuscitation of prolonged hemorrhagic shock; however, the current conventional fluid resuscitation still cannot effectively reduce intestinal injury caused by prolonged hemorrhagic shock. To investigate the effect of ECMO resuscitation on alleviating intestinal ischemia-reperfusion injury in a prolonged hemorrhagic shock rabbit model. Thirty New Zealand white rabbits were randomly divided into three groups: control group, conventional fluid resuscitation group, and ECMO resuscitation group. The prolonged hemorrhagic shock model was established by keeping the arterial blood pressure from 31 to 40 mmHg for 3 h through the femoral artery bleeding, and performing the resuscitation for 2 h by conventional fluid resuscitation and ECMO resuscitation, respectively. Chiu's score of intestinal injury, serum lactate and TNF-α levels, intestinal mucosamyeloperoxidase (MPO) activity, intercellular adhesion molecule (ICAM-1), and Claudin-1expression were detected. The mean arterial blood pressure in Group 2 was significantly higher after resuscitation than in Group 1, but serum lactate and inflammatory cytokines TNF-α level were significantly lower. And Chiu's score of intestinal injury and myeloperoxidase (MPO) activity level and ICAM-1 expression were significantly lower in the ECMO resuscitation group, in which the Claudin-1 levels were significantly increased. ECMO resuscitation for the prolonged hemorrhagic shock improves tissue perfusion and reduces the systemic inflammation, and thus alleviates intestinal damage caused by prolonged hemorrhagic shock.

  17. Prolonged exposure to insulin induces mitochondrion-derived oxidative stress through increasing mitochondrial cholesterol content in hepatocytes.

    PubMed

    Mei, Shuang; Gu, Haihua; Yang, Xuefeng; Guo, Huailan; Liu, Zhenqi; Cao, Wenhong

    2012-05-01

    We addressed the link between excessive exposure to insulin and mitochondrion-derived oxidative stress in this study and found that prolonged exposure to insulin increased mitochondrial cholesterol in cultured hepatocytes and in mice and stimulated production of reactive oxygen species (ROS) and decreased the reduced glutathione to glutathione disulfide ratio in cultured hepatocytes. Exposure of isolated hepatic mitochondria to cholesterol alone promoted ROS emission. The oxidative stress induced by the prolonged exposure to insulin was prevented by inhibition of cholesterol synthesis with simvastatin. We further found that prolonged exposure to insulin decreased mitochondrial membrane potential and the increased ROS production came from mitochondrial respiration complex I. Finally, we observed that prolonged exposure to insulin decreased mitochondrial membrane fluidity in a cholesterol synthesis-dependent manner. Together our results demonstrate that excess exposure to insulin causes mitochondrion-derived oxidative stress through cholesterol synthesis in hepatocytes.

  18. As time goes by: reasons and characteristics of prolonged episodes of mechanical restraint in forensic psychiatry.

    PubMed

    Gildberg, Frederik A; Fristed, Peter; Makransky, Guido; Moeller, Elsebeth H; Nielsen, Lea D; Bradley, Stephen K

    2015-01-01

    Evidence suggests the prevalence and duration of mechanical restraint are particularly high among forensic psychiatric inpatients. However, only sparse knowledge exists regarding the reasons for, and characteristics of, prolonged use of mechanical restraint in forensic psychiatry. This study therefore aimed to investigate prolonged episodes of mechanical restraint on forensic psychiatric inpatients. Documentary data from medical records were thematically analyzed. Results show that the reasons for prolonged episodes of mechanical restraint on forensic psychiatric inpatients can be characterized by multiple factors: "confounding" (behaviors associated with psychiatric conditions, substance abuse, medical noncompliance, etc.), "risk" (behaviors posing a risk for violence), and "alliance parameters" (qualities of the staff-patient alliance and the patients' openness to alliance with staff), altogether woven into a mechanical restraint spiral that in itself becomes a reason for prolonged mechanical restraint. The study also shows lack of consistent clinical assessment during periods of restraint. Further investigation is indicated to develop an assessment tool with the capability to reduce time spent in mechanical restraint.

  19. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity.

    PubMed

    Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R; Kuipers, Eline N; Loef, Marieke; Zonneveld, Tom C M; Lucassen, Eliane A; Sips, Hetty C M; Chatzispyrou, Iliana A; Houtkooper, Riekelt H; Meijer, Johanna H; Coomans, Claudia P; Biermasz, Nienke R; Rensen, Patrick C N

    2015-05-26

    Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity.

  20. Xenon treatment attenuates early renal allograft injury associated with prolonged hypothermic storage in rats.

    PubMed

    Zhao, Hailin; Yoshida, Akira; Xiao, Wei; Ologunde, Rele; O'Dea, Kieran P; Takata, Masao; Tralau-Stewart, Catherine; George, Andrew J T; Ma, Daqing

    2013-10-01

    Prolonged hypothermic storage elicits severe ischemia-reperfusion injury (IRI) to renal grafts, contributing to delayed graft function (DGF) and episodes of acute immune rejection and shortened graft survival. Organoprotective strategies are therefore needed for improving long-term transplant outcome. The aim of this study is to investigate the renoprotective effect of xenon on early allograft injury associated with prolonged hypothermic storage. Xenon exposure enhanced the expression of heat-shock protein 70 (HSP-70) and heme oxygenase 1 (HO-1) and promoted cell survival after hypothermia-hypoxia insult in human proximal tubular (HK-2) cells, which was abolished by HSP-70 or HO-1 siRNA. In the brown Norway to Lewis rat renal transplantation, xenon administered to donor or recipient decreased the renal tubular cell death, inflammation, and MHC II expression, while delayed graft function (DGF) was therefore reduced. Pathological changes associated with acute rejection, including T-cell, macrophage, and fibroblast infiltration, were also decreased with xenon treatment. Donors or recipients treated with xenon in combination with cyclosporin A had prolonged renal allograft survival. Xenon protects allografts against delayed graft function, attenuates acute immune rejection, and enhances graft survival after prolonged hypothermic storage. Furthermore, xenon works additively with cyclosporin A to preserve post-transplant renal function.

  1. Prolonged daily light exposure increases body fat mass through attenuation of brown adipose tissue activity

    PubMed Central

    Kooijman, Sander; van den Berg, Rosa; Ramkisoensing, Ashna; Boon, Mariëtte R.; Kuipers, Eline N.; Loef, Marieke; Zonneveld, Tom C. M.; Lucassen, Eliane A.; Sips, Hetty C. M.; Chatzispyrou, Iliana A.; Houtkooper, Riekelt H.; Meijer, Johanna H.; Coomans, Claudia P.; Biermasz, Nienke R.; Rensen, Patrick C. N.

    2015-01-01

    Disruption of circadian rhythmicity is associated with obesity and related disorders, including type 2 diabetes and cardiovascular disease. Specifically, prolonged artificial light exposure associates with obesity in humans, although the underlying mechanism is unclear. Here, we report that increasing the daily hours of light exposure increases body adiposity through attenuation of brown adipose tissue (BAT) activity, a major contributor of energy expenditure. Mice exposed to a prolonged day length of 16- and 24-h light, compared with regular 12-h light, showed increased adiposity without affecting food intake or locomotor activity. Mechanistically, we demonstrated that prolonged day length decreases sympathetic input into BAT and reduces β3-adrenergic intracellular signaling. Concomitantly, prolonging day length decreased the uptake of fatty acids from triglyceride-rich lipoproteins, as well as of glucose from plasma selectively by BAT. We conclude that impaired BAT activity is an important mediator in the association between disturbed circadian rhythm and adiposity, and anticipate that activation of BAT may overcome the adverse metabolic consequences of disturbed circadian rhythmicity. PMID:25964318

  2. Recovery in skeletal muscle contractile function after prolonged hindlimb immobilization

    NASA Technical Reports Server (NTRS)

    Fitts, R. H.; Brimmer, C. J.

    1985-01-01

    The effect of three-month hindlimb immobilization (IM) in rats on contractile properties of slow-twitch soleus (SOL), fast-twitch extensor digitorum longus, and fast-twitch superficial region of the vastus lateralis were measured after 0, 14, 28, 60, and 90 days of recovery on excized, horizontally suspended muscles stimulated electrically to maximal twitch tension. IM caused decreases in muscle-to-body weight ratios for all muscles, with no complete recovery even after 90 days. The contractile properties of the fast-twitch muscles were less affected by IM than those of the slow-twitch SOL. The SOL isometric twitch duration was shortened, due to reduced contraction and half-relaxation time, both of which returned to control levels after 14 days of recovery. The peak tetanic tension, P(O), g/sq cm,, decreased with IM by 46 percent in the SOL, but recovered by the 28th day. The maximum shortening velocity was not altered by IM in any of the muscles. Thus, normal contractile function could recover after prolonged limb IM.

  3. Cetirizine and loratadine: minimal risk of QT prolongation.

    PubMed

    2010-02-01

    Some antihistamines, such as mizolastine and ebastine, can prolong the QT interval and provoke severe cardiac arrhythmias. This review examines the effects of two widely used antihistamines, cetirizine and loratadine, on the QT interval. As of mid 2009 very few clinical data had been published on the risk of QT prolongation with cetirizine or loratadine. The very rare reported cases of torsades de pointes linked to loratadine mainly appear to involve drug interactions, especially with amiodarone and enzyme inhibitors. We found no reports of QT prolongation attributed to desloratadine, the main metabolite of loratadine. Two cases of QT prolongation with cetirizine have been published, one of which involved overdose and renal failure. The reports are too vague to conclude that cetirizine was implicated. We found no reports of QT prolongation attributed to levocetirizine. Cetirizine is a metabolite of hydroxyzine, another antihistamine. In the 1960s, a study of patients with psychosis showed a risk of QT prolongation. A case of recurrent syncope with QT prolongation has since been reported, along with rare cases of cardiac arrhythmia. In practice, cetirizine and loratadine are first-line antihistamines. However, caution is needed in certain circumstances. In particular, it is best that patients who have risk factors for torsades de pointes or who are taking certain enzyme inhibitors avoid using loratadine. It is best to avoid using cetirizine in cases of renal failure.

  4. Low nonrelapse mortality and prolonged long-term survival after reduced-intensity allogeneic stem cell transplantation for relapsed or refractory diffuse large B cell lymphoma: report of the Société Française de Greffe de Moelle et de Thérapie Cellulaire.

    PubMed

    Sirvent, Anne; Dhedin, Nathalie; Michallet, Mauricette; Mounier, Nicolas; Faucher, Catherine; Yakoub-Agha, Ibrahim; Mohty, Mohamad; Robin, Marie; Tabrizi, Reza; Clement, Laurence; Bilger, Karin; Larosa, Fabrice; Contentin, Nathalie; Huyn, Anne; François, Sylvie; Bulabois, Claude-Eric; Ceballos, Patrice; Bourrhis, Jean-Henri; Buzyn, Agnès; Cornillon, Jérôme; Guillerm, Gaelle; de Revel, Thierry; Bay, Jacques-Olivier; Guilhot, François; Milpied, Noël

    2010-01-01

    Patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) have a very poor prognosis. However, they may achieve long-term survival by undergoing allogeneic stem cell transplantation (SCT). The purpose of this study was to assess the outcome of all adult patients with DLBCL whose treatment included a reduced-intensity conditioning (RIC) regimen for allogeneic SCT and whose data were reported in the French Society of Marrow Transplantation and Cellular Therapy registry. Sixty-eight patients (median age: 48 years) were transplanted from October 1998 to January 2007. They had received a median of 2 regimens of therapy prior to allogeneic SCT, and 54 (79%) had already undergone SCT. Prior to transplantation, 32 patients (47%) were in complete remission (CR). For all patients but 1, conditioning regimens were based on fludarabine (Flu), which was combined with other chemotherapy drugs in 50 cases (74%) and with total body irradiation (TBI) in 17 (25%). For 56 patients (82%), the donor was an HLA-matched sibling, and peripheral blood was the most widely used source of stem cells (57 patients, 84%). With a median follow-up of 49 months, estimated 2-year overall survival (OS), progression-free survival (PFS), and the cumulative incidence of relapse were 49%, 44%, and 41%, respectively. The 1-year cumulative incidence of nonrelapse mortality (NRM) was 23%. According to multivariate analysis, the patients in CR before transplantation had a significantly longer PFS and a lower CI of relapse than patients transplanted during partial remission or stable or progressive disease. These results suggest that reduced-intensity allergenic transplantation is an attractive therapeutic option for patients with high-risk DLBCL.

  5. Reactivity of organism in prolonged space flights

    NASA Technical Reports Server (NTRS)

    Vasilyev, P. V.

    1980-01-01

    An analysis of published data are presented as well as the results of experiments which show that the state of weightlessness and hypodynamia result in a reduced orthostatic and vestibular resistance, increased sensitivity to infections, decreased endurance of accelerations and physical exercises, and altered reactivity of the organism to drugs. Various consequences of weightlessness on the human body, especially weightlessness combined with other factors linked to long space flights are also considered.

  6. Investigation of connexin 43 uncoupling and prolongation of the cardiac QRS complex in preclinical and marketed drugs

    PubMed Central

    Burnham, M P; Sharpe, P M; Garner, C; Hughes, R; Pollard, C E; Bowes, J

    2014-01-01

    Background and Purpose Prolongation of the cardiac QRS complex is linked to increased mortality and may result from drug-induced inhibition of cardiac sodium channels (hNaV1.5). There has been no systematic evaluation of preclinical and marketed drugs for their additional potential to cause QRS prolongation via gap junction uncoupling. Experimental Approach Using the human cardiac gap junction connexin 43 (hCx43), a dye transfer ‘parachute’ assay to determine IC50 values for compound ranking was validated with compounds known to uncouple gap junctions. Uncoupling activity (and hNaV1.5 inhibition by automated patch clamp) was determined in a set of marketed drugs and preclinical candidate drugs, each with information regarding propensity to prolong QRS. Key Results The potency of known gap junction uncouplers to uncouple hCx43 was ranked (according to IC50) as phorbol ester>digoxin>meclofenamic acid>carbenoxolone>heptanol. Among the drugs associated with QRS prolongation, 29% were found to uncouple hCx43 (IC50 < 50 μM), whereas no uncoupling activity was observed in drugs not associated with QRS prolongation. In preclinical candidate drugs, hCx43 and hNaV1.5 IC50 values were similar (within threefold). No consistent margin over preclinical Cmax (free) was apparent for QRS prolongation associated with Cx43 inhibition. However, instances were found of QRS prolonging compounds that uncoupled hCx43 with significantly less activity at hNaV1.5. Conclusion and Implications These results demonstrate that off-target uncoupling activity is apparent in drug and drug-like molecules. Although the full ramifications of Cx inhibition remain to be established, screening for hCx43 off-target activity could reduce the likelihood of developing candidate drugs with a risk of causing QRS prolongation. PMID:24328991

  7. Prolonged Antibiotic Use Tied to Precancerous Colon Growths

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_164445.html Prolonged Antibiotic Use Tied to Precancerous Colon Growths Drugs that ... 2017 TUESDAY, April 4, 2017 (HealthDay News) -- Taking antibiotics for an extended period in early to middle ...

  8. Corticosteroid-responsive prolonged thrombocytopenia following dengue haemorrhagic fever.

    PubMed

    Leong, K W; Srinivas, P

    1993-09-01

    A case of prolonged thrombocytopenia following dengue haemorrhagic fever in a 15 year old boy is reported. The mechanism was presumed to be immunological and he responded dramatically to oral prednisolone.

  9. Prolongation of RBC survival in the hypophysectomized rat.

    NASA Technical Reports Server (NTRS)

    Landaw, S. A.; Bristol, S. K.

    1971-01-01

    Red blood cell (RBC) survival was prolonged in hypophysectomized rats. While the rate of random hemolysis was decreased in some hypophysectomized hosts, in all directly injected and cross-transfused hypophysectomized rat hosts, there was a significant prolongation of the phase of senescent death. In contrast, RBCs from hypophysectomized donors survived normally in normal hosts. These experiments are further evidence of a relationship between RBC aging and metabolic rate, and suggest an intimate involvement with the calorigenic hormones.

  10. Identifying Molecular Targets For PTSD Treatment Using Single Prolonged Stress

    DTIC Science & Technology

    2014-10-01

    AWARD NUMBER: W81XWH-13-1-0377 TITLE: Identifying Molecular Targets For PTSD Treatment Using Single ...Targets For PTSD Treatment Using Single Prolonged Stress 5b. GRANT NUMBER W81XWH-13-1-0377 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...on Specific Aims 3 and 4 ahead of schedule. 15. SUBJECT TERMS PTSD, Single Prolonged Stress, Neurobiological Mechanisms 16. SECURITY

  11. Two cases of lichen striatus with prolonged active phase.

    PubMed

    Feely, Meghan A; Silverberg, Nanette B

    2014-01-01

    Lichen striatus is a localized, eczematous disorder distributed along the lines of Blaschko, primarily affecting children. In the literature, lesions have been described as having an active phase of inflamed lesions for 6 to 12 months followed by flattening and persistent pigmentary alteration. We describe two girls who had prolonged active-phase lesions for 2.5 and 3.5 years, respectively. Practitioners should be aware that lesions of lichen striatus may have a prolonged active phase.

  12. QTc interval prolongation in patients with HIV and AIDS.

    PubMed Central

    Sani, Mahmoud U.; Okeahialam, Basil N.

    2005-01-01

    A higher prevalence of QT prolongation has been reported among HIV/AIDS patients, possibly related to drugs prescribed for them or to an acquired form of long QT syndrome. A prolonged QTc is a predictor of cardiovascular mortality. We set out to study this interval in a group of AIDS patients. One-hundred consecutive AIDS patients admitted into the Jos University Teaching Hospital and who satisfied the inclusion criteria were recruited. All were evaluated for symptomatology of cardiovascular disease and had a 12-lead surface electrocardiogram recording. QT interval, taken from the onset of the QRS complex to the end of the T wave, was corrected for heart rate. Eighty HIV-negative, healthy persons and 78 HIV-positive, asymptomatic subjects were used as controls. Forty-five percent of the AIDS patients had prolonged QTc interval. Prolonged QTc was present in 28% of HIV-positive controls and 10% of HIV-negative controls. The mean QTc interval differs significantly between the AIDS patients and the two control groups. From our study, Nigerian HIV-positive asymptomatic subjects have higher prevalence of QTc prolongation compared to HIV-negative subjects and, as they move to AIDS, the prevalence of QTc prolongation increases. This makes for increased cardiovascular mortality. PMID:16396057

  13. Outcome of Induction of Labour in Prolonged Pregnancy.

    PubMed

    Nasrin, S; Islam, S; Shahida, S M; Begum, R A; Haque, N

    2015-10-01

    This was a hospital based prospective clinical study conducted among women having prolonged pregnancy to assess the outcome of induction of labour in prolonged pregnancy cases. One hundred and thirty nine women having uncomplicated prolonged pregnancy were studied. The study was carried out in Sir Salimullah Medical College & Mitford Hospital, Dhaka from 01 July 2010 to 30 March 2011. In this study 66% of the respondents had vaginal delivery on routine induction of labour and in 34% cases induction failed. Ninety three percent (93%) of the multigravida had vaginal delivery and in primigravida their vaginal delivery rate was 47.5%. Regarding cervical condition for delivery, 75% of the respondents having favourable cervix had vaginal delivery and in case of unfavourable cervix respondents, they had 55% cases of vaginal delivery. About the foetal outcome it was evidenced from this study that the perinatal adverse outcome increases with the increasing age of gestation beyond 40 completed weeks of gestation. This study showed that the use of prostaglandins for cervical ripening and by confirming the diagnosis of prolonged pregnancy, the delivery outcome in prolonged pregnancy can be improved. The study also showed that induction of labour is not associated with any major complications and the routine induction of labour in prolonged pregnancy is beneficial for both mother and the baby.

  14. Benefits of rice seed priming are offset permanently by prolonged storage and the storage conditions.

    PubMed

    Hussain, Saddam; Zheng, Manman; Khan, Fahad; Khaliq, Abdul; Fahad, Shah; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

    2015-01-29

    Seed priming is a commercially successful practice, but reduced longevity of primed seeds during storage may limit its application. We established a series of experiments on rice to test: (1) whether prolonged storage of primed and non-primed rice seeds for 210 days at 25°C or -4°C would alter their viability, (2) how long primed rice seed would potentially remain viable at 25°C storage, and (3) whether or not post-storage treatments (re-priming or heating) would reinstate the viability of stored primed seeds. Two different rice cultivars and three priming agents were used in all experiments. Prolonged storage of primed seeds at 25°C significantly reduced the germination (>90%) and growth attributes (>80%) of rice compared with un-stored primed seeds. However, such negative effects were not observed in primed seeds stored at -4°C. Beneficial effects of seed priming were maintained only for 15 days of storage at 25°C, beyond which the performance of primed seeds was worse even than non-primed seeds. The deteriorative effects of 25°C storage were related with hampered starch metabolism in primed rice seeds. None of the post-storage treatments could reinstate the lost viability of primed seeds suggesting that seeds become unviable by prolonged post-priming storage at 25°C.

  15. Benefits of rice seed priming are offset permanently by prolonged storage and the storage conditions

    PubMed Central

    Hussain, Saddam; Zheng, Manman; Khan, Fahad; Khaliq, Abdul; Fahad, Shah; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Nie, Lixiao

    2015-01-01

    Seed priming is a commercially successful practice, but reduced longevity of primed seeds during storage may limit its application. We established a series of experiments on rice to test: (1) whether prolonged storage of primed and non-primed rice seeds for 210 days at 25°C or −4°C would alter their viability, (2) how long primed rice seed would potentially remain viable at 25°C storage, and (3) whether or not post-storage treatments (re-priming or heating) would reinstate the viability of stored primed seeds. Two different rice cultivars and three priming agents were used in all experiments. Prolonged storage of primed seeds at 25°C significantly reduced the germination (>90%) and growth attributes (>80%) of rice compared with un-stored primed seeds. However, such negative effects were not observed in primed seeds stored at −4°C. Beneficial effects of seed priming were maintained only for 15 days of storage at 25°C, beyond which the performance of primed seeds was worse even than non-primed seeds. The deteriorative effects of 25°C storage were related with hampered starch metabolism in primed rice seeds. None of the post-storage treatments could reinstate the lost viability of primed seeds suggesting that seeds become unviable by prolonged post-priming storage at 25°C. PMID:25631923

  16. Alk7 Depleted Mice Exhibit Prolonged Cardiac Repolarization and Are Predisposed to Ventricular Arrhythmia

    PubMed Central

    Ying, Shaozhen; Cao, Hong; Hu, He; Wang, Xin; Tang, Yanhong; Huang, Congxin

    2016-01-01

    We aimed to investigate the role of activin receptor-like kinase (ALK7) in regulating cardiac electrophysiology. Here, we showed that Alk7-/- mice exhibited prolonged QT intervals in telemetry ECG recordings. Furthermore, Langendorff-perfused Alk7-/- hearts had significantly longer action potential duration (APD) and greater incidence of ventricular arrhythmia (AV) induced by burst pacing. Using whole-cell patch clamp, we found that the densities of repolarizing K+ currents Ito and IK1 were profoundly reduced in Alk7-/- ventricular cardiomyocytes. Mechanistically, the expression of Kv4.2 (a major subunit of Ito carrying channel) and KCHIP2 (a key accessory subunit of Ito carrying channel), was markedly decreased in Alk7-/- hearts. These findings suggest that endogenous expression of ALK7 is necessary to maintain repolarizing K+ currents in ventricular cardiomyocytes, and finally prevent action potential prolongation and ventricular arrhythmia. PMID:26882027

  17. [Use of benzodiazepines in prolonged seizures and status epilepticus in the community].

    PubMed

    Sánchez-Carpintero, R; Camino, R; Smeyers, P; Raspall-Chaure, M; Martínez-Bermejo, A; Ruiz-Falcó, M L; Verdú, A; Sanmarti, F X; Blanco, O; Santos Borbujo, J; Picó, G; Cebollero, M A

    2014-12-01

    Prolonged seizures and status epilepticus are common neurological medical emergencies. Early and appropriate treatment is essential to reduce morbidity and mortality. Most seizures occur in the community, so parents and caregivers must be prepared for their management. Benzodiazepines (BZD) are the first-line drugs used, with rectal diazepam (DZPr) being the most commonly used in pre-hospital treatment in Spain. In September 2011, the European Medicines Agency (EMA) authorized the use of oromucosal midazolam (MDZb) for the treatment of prolonged acute convulsive seizures in patients aged 3 months to <18 years. MDZb has a rapid onset, short duration of effect, and avoids first-pass hepatic metabolism. MDZb has shown to be at least as or more effective than DZPr to stop the seizures. Buccal administration is easier and more socially accepted, especially in adolescents and adults. It is a safe drug with similar effects to other BZD; MDZb improves the overall cost-effectiveness of seizures management.

  18. Alpha1-antitrypsin monotherapy prolongs islet allograft survival in mice.

    PubMed

    Lewis, Eli C; Shapiro, Leland; Bowers, Owen J; Dinarello, Charles A

    2005-08-23

    Islet transplantation for type 1 diabetic patients shows promising results with the use of nondiabetogenic immunosuppressive therapy. However, in addition to compromising the immune system of transplant recipients, long-term studies demonstrate that islet viability is impaired. Here, we demonstrate that, in the absence of immunosuppressive agents, monotherapy with clinical-grade human alpha1-antitrypsin (hAAT), the major serum serine-protease inhibitor, prolongs islet graft survival and normoglycemia in transplanted allogeneic diabetic mice, lasting until the development of anti-hAAT antibodies. Compared to untreated or albumin-control-treated graft recipients, which rejected islets at day 10, AAT-treated mice displayed diminished cellular infiltrates and intact intragraft insulin production throughout treatment. Using peritoneal infiltration models, we demonstrate that AAT decreases allogeneic fibroblast-elicited natural-killer-cell influx by 89%, CD3-positive cell influx by 44%, and thioglycolate-elicited neutrophil emigration by 66%. ATT also extended islet viability in mice after streptozotocin-induced beta cell toxicity. In vitro, several islet responses to IL-1beta/IFNgamma stimulation were examined. In the presence of AAT, islets displayed enhanced viability and inducible insulin secretion. Islets also released 36% less nitric oxide and 82% less macrophage inflammatory protein 1 alpha and expressed 63% fewer surface MHC class II molecules. TNFalpha release from IL-1beta/IFNgamma-stimulated islet cells was reduced by 99%, accompanied by an 8-fold increase in the accumulation of membrane TNFalpha on CD45-positive islet cells. In light of the established safety record and the nondiabetogenic potential of AAT, these data suggest that AAT may be beneficial as adjunctive therapy in patients undergoing islet transplantation.

  19. Prolonged cannabis withdrawal in young adults with lifetime psychiatric illness.

    PubMed

    Schuster, Randi Melissa; Fontaine, Madeleine; Nip, Emily; Zhang, Haiyue; Hanly, Ailish; Eden Evins, A

    2017-02-27

    Young adults with psychiatric illnesses are more likely to use cannabis and experience problems from use. It is not known whether those with a lifetime psychiatric illness experience a prolonged cannabis withdrawal syndrome with abstinence. Participants were fifty young adults, aged 18-25, recruited from the Boston-area in 2015-2016, who used cannabis at least weekly, completed the Structured Clinical Interview for DSM-IV to identify Axis I psychiatric diagnoses (PD+ vs PD-), and attained cannabis abstinence with a four-week contingency management protocol. Withdrawal symptom severity was assessed at baseline and at four weekly abstinent visits using the Cannabis Withdrawal Scale. Cannabis dependence, age of initiation, and rate of abstinence were similar in PD+ and PD- groups. There was a diagnostic group by abstinent week interaction, suggesting a difference in time course for resolution of withdrawal symptoms by group, F(4,46)=3.8, p=0.009, controlling for sex, baseline depressive and anxiety symptoms, and frequency of cannabis use in the prior 90days. In post hoc analyses, there was a difference in time-course of cannabis withdrawal. PD- had significantly reduced withdrawal symptom severity in abstinent week one [t(46)=-2.2, p=0.03], while PD+ did not report improved withdrawal symptoms until the second abstinent week [t(46)=-4.1, p=0.0002]. Cannabis withdrawal symptoms improved over four weeks in young people with and without a lifetime psychiatric diagnosis. However, those with a psychiatric illness reported one week delayed improvement in withdrawal symptom severity. Longer duration of cannabis withdrawal may be a risk factor for cannabis dependence and difficulty quitting.

  20. Anti-CD45 radioimmunotherapy using 211At with bone marrow transplantation prolongs survival in a disseminated murine leukemia model

    SciTech Connect

    Orozco, Johnnie J.; Back, Tom; Kenoyer, Aimee L.; Balkin, Ethan R.; Hamlin, Donald K.; Wilbur, D. Scott; Fisher, Darrell R.; Frayo, Shani; Hylarides, Mark; Green, Damian J.; Gopal, Ajay K.; Press, Oliver W.; Pagel, John M.

    2013-05-15

    Anti-CD45 Radioimmunotherapy using an Alpha-Emitting Radionuclide 211At Combined with Bone Marrow Transplantation Prolongs Survival in a Disseminated Murine Leukemia Model ABSTRACT Despite aggressive chemotherapy combined with hematopoietic cell transplant (HCT), many patients with acute myeloid leukemia (AML) relapse. Radioimmunotherapy (RIT) using antibodies (Ab) labeled primarily with beta-emitting radionuclides has been explored to reduce relapse.

  1. Pharmacometabolomic Approach to Predict QT Prolongation in Guinea Pigs

    PubMed Central

    Lee, Hae Won; Lim, Mi-sun; Seong, Sook Jin; Seo, Jeong Ju; Kim, Eun-Jung; Kang, Wonku; Yoon, Young-Ran

    2013-01-01

    Drug-induced torsades de pointes (TdP), a life-threatening arrhythmia associated with prolongation of the QT interval, has been a significant reason for withdrawal of several medicines from the market. Prolongation of the QT interval is considered as the best biomarker for predicting the torsadogenic risk of a new chemical entity. Because of the difficulty assessing the risk for TdP during drug development, we evaluated the metabolic phenotype for predicting QT prolongation induced by sparfloxacin, and elucidated the metabolic pathway related to the QT prolongation. We performed electrocardiography analysis and liquid chromatography–mass spectroscopy-based metabolic profiling of plasma samples obtained from 15 guinea pigs after administration of sparfloxacin at doses of 33.3, 100, and 300 mg/kg. Principal component analysis and partial least squares modelling were conducted to select the metabolites that substantially contributed to the prediction of QT prolongation. QTc increased significantly with increasing dose (r = 0.93). From the PLS analysis, the key metabolites that showed the highest variable importance in the projection values (>1.5) were selected, identified, and used to determine the metabolic network. In particular, cytidine-5′-diphosphate (CDP), deoxycorticosterone, L-aspartic acid and stearic acid were found to be final metabolomic phenotypes for the prediction of QT prolongation. Metabolomic phenotypes for predicting drug-induced QT prolongation of sparfloxacin were developed and can be applied to cardiac toxicity screening of other drugs. In addition, this integrative pharmacometabolomic approach would serve as a good tool for predicting pharmacodynamic or toxicological effects caused by changes in dose. PMID:23593245

  2. From prolonging life to prolonging working life: Tackling unemployment among liver-transplant recipients

    PubMed Central

    Åberg, Fredrik

    2016-01-01

    Return to active and productive life is a key goal of modern liver transplantation (LT). Despite marked improvements in quality of life and functional status, a substantial proportion of LT recipients are unable to resume gainful employment. Unemployment forms a threat to physical and psychosocial health, and impairs LT cost-utility through lost productivity. In studies published after year 2000, the average post-LT employment rate is 37%, ranging from 22% to 55% by study. Significant heterogeneity exists among studies. Nonetheless, these employment rates are lower than in the general population and kidney-transplant population. Most consistent employment predictors include pre-LT employment status, male gender, functional/health status, and subjective work ability. Work ability is impaired by physical fatigue and depression, but affected also by working conditions and society. Promotion of post-LT employment is hampered by a lack of interventional studies. Prevention of pre-LT disability by effective treatment of (minimal) hepatic encephalopathy, maintaining mobility, and planning work adjustments early in the course of chronic liver disease, as well as timely post-LT physical rehabilitation, continuous encouragement, self-efficacy improvements, and depression management are key elements of successful employment-promoting strategies. Prolonging LT recipients’ working life would further strengthen the success of transplantation, and this is likely best achieved through multidisciplinary efforts ideally starting even before LT candidacy. PMID:27076755

  3. Correcting magnesium deficiencies may prolong life

    PubMed Central

    Rowe, William J

    2012-01-01

    The International Space Station provides an extraordinary facility to study the accelerated aging process in microgravity, which could be triggered by significant reductions in magnesium (Mg) ion levels with, in turn, elevations of catecholamines and vicious cycles between the two. With space flight there are significant reductions of serum Mg (P < 0.0001) that have been shown in large studies of astronauts and cosmonauts. The loss of the functional capacity of the cardiovascular system with space flight is over ten times faster than the course of aging on Earth. Mg is an antioxidant and calcium blocker and in space there is oxidative stress, insulin resistance, and inflammatory conditions with evidence in experimental animals of significant endothelial injuries and damage to mitochondria. The aging process is associated with progressive shortening of telomeres, repetitive DNA sequences, and proteins that cap and protect the ends of chromosomes. Telomerase can elongate pre-existing telomeres to maintain length and chromosome stability. Low telomerase triggers increased catecholamines while the sensitivity of telomere synthesis to Mg ions is primarily seen for the longer elongation products. Mg stabilizes DNA and promotes DNA replication and transcription, whereas low Mg might accelerate cellular senescence by reducing DNA stability, protein synthesis, and function of mitochondria. Telomerase, in binding to short DNAs, is Mg dependent. On Earth, in humans, a year might be required to detect changes in telomeres, but in space there is a predictably much shorter duration required for detection, which is therefore more reasonable in time and cost. Before and after a space mission, telomere lengths and telomerase enzyme activity can be determined and compared with age-matched control rats on Earth. The effect of Mg supplementation, both on maintaining telomere length and extending the life span, can be evaluated. Similar studies in astronauts would be fruitful. PMID

  4. No Evidence for Prolonged Visible Persistence in Patients with Schizophrenia

    PubMed Central

    Grimsen, Cathleen; Brand, Andreas; Fahle, Manfred

    2013-01-01

    Background Temporal visual processing is strongly deteriorated in patients with schizophrenia. For example, the interval required between a visual stimulus and a subsequent mask has to be much longer in schizophrenic patients than in healthy controls. We investigated whether this deficit in temporal resolution is accompanied by prolonged visual persistence and/or deficient temporal precision (temporal asynchrony perception). Methodology/Principal Findings We investigated visual persistence in three experiments. In the first, measuring temporal processing by so-called backward masking, prolonged visible persistence is supposed to decrease performance. In the second experiment, requiring temporal integration, prolonged persistence is supposed to improve performance. In the third experiment, we investigated asynchrony detection, as another measure of temporal resolution. Eighteen patients with schizophrenia and 15 healthy controls participated. Asynchrony detection was intact in the patients. However, patients' performance was inferior compared to healthy controls in the first two experiments. Hence, temporal processing in schizophrenic patients is indeed significantly impaired but this impairment is not caused by prolonged temporal integration. Conclusions/Significance Our results argue against a generally prolonged visual persistence in patients with schizophrenia. Together with the preserved ability of patients, to detect temporal asynchronies in permanently presented stimuli, the results indicate a more specific deficit in temporal processing of schizophrenic patients. PMID:23536838

  5. Integration of asynchronously released quanta prolongs the postsynaptic spike window.

    PubMed

    Iremonger, Karl J; Bains, Jaideep S

    2007-06-20

    Classically, the release of glutamate in response to a presynaptic action potential causes a brief increase in postsynaptic excitability. Previous reports indicate that at some central synapses, a single action potential can elicit multiple, asynchronous release events. This raises the possibility that the temporal dynamics of neurotransmitter release may determine the duration of altered postsynaptic excitability. In response to physiological challenges, the magnocellular neurosecretory cells (MNCs) in the paraventricular nucleus of the hypothalamus (PVN) exhibit robust and prolonged increases in neuronal activity. Although the postsynaptic conductances that may facilitate this form of activity have been investigated thoroughly, the role of presynaptic release has been largely overlooked. Because the specific patterns of activity generated by MNCs require the activation of excitatory synaptic inputs, we sought to characterize the release dynamics at these synapses and determine whether they contribute to prolonged excitability in these cells. We obtained whole-cell recordings from MNCs in brain slices of postnatal day 21-44 rats. Stimulation of glutamatergic inputs elicited large and prolonged postsynaptic events that resulted from the summation of multiple, asynchronously released quanta. Asynchronous release was selectively inhibited by the slow calcium buffer EGTA-AM and potentiated by brief high-frequency stimulus trains. These trains caused a prolonged increase in postsynaptic spike activity that could also be eliminated by EGTA-AM. Our results demonstrate that glutamatergic terminals in PVN exhibit asynchronous release, which is important in generating large postsynaptic depolarizations and prolonged spiking in response to brief, high-frequency bursts of presynaptic activity.

  6. l-Carnitine supplement reduces skeletal muscle atrophy induced by prolonged hindlimb suspension in rats.

    PubMed

    Jang, Jiwoong; Park, Jonghoon; Chang, Hyukki; Lim, Kiwon

    2016-12-01

    l-Carnitine was recently found to downregulate the ubiquitin proteasome pathway (UPP) and increase insulin-like growth factor 1 concentrations in animal models. However, the effect of l-carnitine administration on disuse muscle atrophy induced by hindlimb suspension has not yet been studied. Thus, we hypothesized that l-carnitine may have a protective effect on muscle atrophy induced by hindlimb suspension via the Akt1/mTOR and/or UPP. Male Wistar rats were assigned to 3 groups: hindlimb suspension group, hindlimb suspension with l-carnitine administration (1250 mg·kg(-1)·day(-1)) group, and pair-fed group adjusted hindlimb suspension. l-Carnitine administration for 2 weeks of hindlimb suspension alleviated the decrease in weight and fiber size in the soleus muscle. In addition, l-carnitine suppressed atrogin-1 mRNA expression, which has been reported to play a pivotal role in muscle atrophy. The present study shows that l-carnitine has a protective effect against soleus muscle atrophy caused by hindlimb suspension and decreased E3 ligase messenger RNA expression, suggesting the possibility that l-carnitine protects against muscle atrophy, at least in part, through the inhibition of the UPP. These observations suggest that l-carnitine could serve as an effective supplement in the decrease of muscle atrophy caused by weightlessness in the fields of clinical and rehabilitative research.

  7. Unusually Prolonged Presentation of Designer Drug Encephalopathy Responsive to Steroids.

    PubMed

    Albadareen, Rawan; Thornton, Stephen; Heshmati, Arezou; Gerona, Roy; Lowry, Jennifer

    2015-07-01

    The availability and use of novel psychoactive substances has risen dramatically over the last decade. The unpredictability of their toxicity constitutes a real challenge. We report a case of an adolescent who developed prolonged encephalopathy after ingesting "Hot Molly," which was found to contain the novel psychoactive substance, methylenedioxybenzylpiperazine when analyzed by high resolution mass spectrometry assay. This is the first case of human toxicity from methylenedioxybenzylpiperazine ingestion in the medical literature confirmed by body fluid analysis presenting with significant and prolonged encephalopathy. The prolonged course may be due to CYP2D6 inhibition from a combination of the methylenedioxyphenyl moiety and the patient's ultrarapid metabolizer pharmacokinetics. The response to high dose corticosteroids suggests a possible inflammatory effect that warrants further investigation.

  8. Prolonged Eyelid Closure Episodes during Sleep Deprivation in Professional Drivers

    PubMed Central

    Alvaro, Pasquale K.; Jackson, Melinda L.; Berlowitz, David J.; Swann, Philip; Howard, Mark E.

    2016-01-01

    Study Objectives: Real life ocular measures of drowsiness use average blink duration, amplitude and velocity of eyelid movements to reflect drowsiness in drivers. However, averaged data may conceal the variability in duration of eyelid closure episodes, and more prolonged episodes that indicate higher levels of drowsiness. The current study aimed to describe the frequency and duration of prolonged eyelid closure episodes during acute sleep deprivation. Methods: Twenty male professional drivers (mean age ± standard deviation = 41.9 ± 8.3 years) were recruited from the Transport Workers Union newsletter and newspaper advertisements in Melbourne, Australia. Each participant underwent 24 hours of sleep deprivation and completed a simulated driving task (AusEd), the Psychomotor Vigilance Task, and the Karolinska Sleepiness Scale. Eyelid closure episodes during the driving task were recorded and analyzed manually from digital video recordings. Results: Eyelid closure episodes increased in frequency and duration with a median of zero s/h of eyelid closure after 3 h increasing to 34 s/h after 23 h awake. Eyelid closure episodes were short and infrequent from 3 to 14 h of wakefulness. After 17 h of sleep deprivation, longer and more frequent eyelid closure episodes began to occur. Episodes lasting from 7 seconds up to 18 seconds developed after 20 h of wakefulness. Length of eyelid closure episodes was moderately to highly correlated with the standard deviation of lateral lane position, braking reaction time, crashes, impaired vigilance, and subjective sleepiness. Conclusions: The frequency and duration of episodes of prolonged eyelid closure increases during acute sleep deprivation, with very prolonged episodes after 17 hours awake. Automated devices that assess drowsiness using averaged measures of eyelid closure episodes need to be able to detect prolonged eyelid closure episodes that occur during more severe sleep deprivation. Citation: Alvaro PK, Jackson ML

  9. The influence of a seated break on prolonged standing induced low back pain development.

    PubMed

    Gallagher, Kaitlin M; Campbell, Troy; Callaghan, Jack P

    2014-01-01

    With the recent attention to 'sitting disease', health practitioners and scientists are promoting standing in the workplace to decrease sedentary time, despite a high prevalence of low back pain (LBP) development during prolonged standing. The purpose of this study was to assess how a seated break inserted between bouts of prolonged standing would influence LBP development, posture and movement. A total of 20 participants stood for 45 minutes, sat for 15 minutes and repeated this sequence while lumbar and thoracic angles were measured, and LBP visual analogue scale reports were taken. Of the sample, 55% participants reported LBP in standing. A stand to sit ratio of 3:1 did not provide lasting recovery of LBP from standing and pain developers utilised a limited range of their lumbar spine angle and increased thoracic extension, resulting in static postures that caused tissue aggravation that was not resolved after 15 minutes of sitting. Prolonged standing in the workplace has the potential to result in LBP for some workers and alternate ways to reduce sedentary time should be investigated.

  10. Efficacy of metacognitive therapy for prolonged grief disorder: protocol for a randomised controlled trial

    PubMed Central

    Wenn, Jenine; O'Connor, Moira; Breen, Lauren J; Kane, Robert T; Rees, Clare S

    2015-01-01

    Introduction Studies of effective psychotherapy for individuals suffering from the effects of prolonged grief disorder (PGD) are scarce. This paper describes the protocol for an evaluation of a metacognitive therapy programme designed specifically for PGD, to reduce the psychological distress and loss of functioning resulting from bereavement. Methods and analysis The proposed trial comprises three phases. Phase 1 consists of a review of the literature and semistructured interviews with key members of the target population to inform the development of a metacognitive therapy programme for Prolonged Grief. Phase 2 involves a randomised controlled trial to implement and evaluate the programme. Male and female adults (N=34) will be randomly assigned to either a wait list or an intervention group. Measures of PGD, anxiety, depression, rumination, metacognitions and quality of life will be taken pretreatment and posttreatment and at the 3-month and 6-month follow-up. The generalised linear mixed model will be used to assess treatment efficacy. Phase 3 will test the social validity of the programme. Discussion This study is the first empirical investigation of the efficacy of a targeted metacognitive treatment programme for PGD. A focus on identifying and changing the metacognitive mechanisms underpinning the development and maintenance of prolonged grief is likely to be beneficial to theory and practice. Ethics Ethics approval was obtained from Curtin University Human Research Ethics Committee (Approval number HR 41/2013.) Trial registration number ACTRN12613001270707. PMID:26646828

  11. The effect of estrogen on muscle damage biomarkers following prolonged aerobic exercise in eumenorrheic women

    PubMed Central

    Walz, E; Lane, AR; Pebole, M; Hackney, AC

    2015-01-01

    This study assessed the influence of estrogen (E2) on muscle damage biomarkers [skeletal muscle - creatine kinase (CK); cardiac muscle - CK-MB] responses to prolonged aerobic exercise. Eumenorrheic women (n=10) who were physically active completed two 60-minute treadmill running sessions at ∼60-65% maximal intensity during low E2 (midfollicular menstrual phase) and high E2 (midluteal menstrual phase) hormonal conditions. Blood samples were collected prior to exercise (following supine rest), immediately post-, 30 min post-, and 24 hours post-exercise to determine changes in muscle biomarkers. Resting blood samples confirmed appropriate E2 hormonal levels Total CK concentrations increased following exercise and at 24 hours post-exercise were higher in the midfollicular low E2 phase (p<0.001). However, CK-MB concentrations were unaffected by E2 level or exercise (p=0.442) resulting in the ratio of CK-MB to total CK being consistently low in subject responses (i.e., indicative of skeletal muscle damage). Elevated E2 levels reduce the CK responses of skeletal muscle, but had no effect on CK-MB responses following prolonged aerobic exercise. These findings support earlier work showing elevated E2 is protective of skeletal muscle from exercise-induced damage associated with prolonged aerobic exercise. PMID:26424921

  12. Prolongation of survival of rat cardiac allografts by T cell vaccination.

    PubMed Central

    Shapira, O M; Mor, E; Reshef, T; Pfeffermann, R A; Cohen, I R

    1993-01-01

    Administration of attenuated, activated autoimmune T lymphocytes to syngeneic mice and rats has been shown to prevent or induce remission of experimental autoimmune diseases specific for the autoimmune T cells. The process has been termed "T cell vaccination." In a recent study, T cell vaccination was done using T cells sensitized to rat alloantigens. The procedure produced a significant reduction of the mixed lymphocyte reaction (MLR) against allogeneic cells. The reduction in MLR was not specific: Vaccination with T cells specific for stimulator cells of one allotype led to a reduced MLR stimulated by cells of another allotype. The present study was undertaken to examine whether T cell vaccination can induce tolerance to transplantation antigens in vivo. We used the model of heterotopic cardiac transplantation in rats. We now report that vaccinating rats with syngeneic, activated, alloantigen-primed T lymphocytes significantly prolonged survival of rat cardiac allografts. The effect of T cell vaccination was most evident when the T cells had been obtained from rats specifically sensitized against the donor rats: Brown-Norway (BN) allografts in control Wistar rats survived 8.5 +/- 0.4 d while BN allografts survived 29.2 +/- 7.1 d in Wistar rats that had been vaccinated with Wistar anti-BN cells. Vaccination of Wistar rats with Wistar anti-hooded T cells prolonged survival of BN heart allografts to a lesser but significant degree (13.0 +/- 1.1 d). Thus, T cell vaccination of recipients can prolong survival of allografts. PMID:8432846

  13. Xenon treatment protects against cold ischemia associated delayed graft function and prolongs graft survival in rats.

    PubMed

    Zhao, H; Watts, H R; Chong, M; Huang, H; Tralau-Stewart, C; Maxwell, P H; Maze, M; George, A J T; Ma, D

    2013-08-01

    Prolonged hypothermic storage causes ischemia-reperfusion injury (IRI) in the renal graft, which is considered to contribute to the occurrence of the delayed graft function (DGF) and chronic graft failure. Strategies are required to protect the graft and to prolong renal graft survival. We demonstrated that xenon exposure to human proximal tubular cells (HK-2) led to activation of range of protective proteins. Xenon treatment prior to or after hypothermia-hypoxia challenge stabilized the HK-2 cellular structure, diminished cytoplasmic translocation of high-mobility group box (HMGB) 1 and suppressed NF-κB activation. In the syngeneic Lewis-to-Lewis rat model of kidney transplantation, xenon exposure to donors before graft retrieval or to recipients after engraftment decreased caspase-3 expression, localized HMGB-1 within nuclei and prevented TLR-4/NF-κB activation in tubular cells; serum pro-inflammatory cytokines IL-1β, IL-6 and TNF-α were reduced and renal function was preserved. Xenon treatment of graft donors or of recipients prolonged renal graft survival following IRI in both Lewis-to-Lewis isografts and Fischer-to-Lewis allografts. Xenon induced cell survival or graft functional recovery was abolished by HIF-1α siRNA. Our data suggest that xenon treatment attenuates DGF and enhances graft survival. This approach could be translated into clinical practice leading to a considerable improvement in long-term graft survival.

  14. Ionic, molecular, and cellular bases of QT-interval prolongation and torsade de pointes

    PubMed Central

    Antzelevitch, Charles

    2008-01-01

    Torsade de pointes (TdP) is a life-threatening arrhythmia that develops as a consequence of a reduction in the repolarization reserve of cardiac cells leading to amplification of electrical heterogeneities in the ventricular myocardium as well as to the development of early after depolarization-induced triggered activity. Electrical heterogeneities within the ventricles are due to differences in the time course of repolarization of the three predominant cell types that make up the ventricular myocardium, giving rise to transmural voltage gradients and a dispersion of repolarization that contributes to the inscription of the electrocardiographic T wave. A number of non-antiarrhythmic drugs and antiarrhythmic agents with class III actions and/or the various mutations and cardiomyopathies associated with the long QT syndrome reduce net repolarizing current and amplify spatial dispersion of repolarization, thus creating the substrate for re-entry. This results in a prolongation of the QT interval, abnormal T waves, and development of TdP. Agents that prolong the QT interval but do not cause an increase in transmural dispersion of repolarization (TDR) do not induce TdP, suggesting that QT prolongation is not the sole or optimal determinant for arrhythmogenesis. This article reviews recent advances in our understanding of these mechanisms, particularly the role of TDR in the genesis of drug-induced TdP, and examines how these may guide us towards development of safer drugs. PMID:17766323

  15. Bartonella henselae Infective Endocarditis Detected by a Prolonged Blood Culture.

    PubMed

    Mito, Tsutomu; Hirota, Yusuke; Suzuki, Shingo; Noda, Kazutaka; Uehara, Takanori; Ohira, Yoshiyuki; Ikusaka, Masatomi

    A 65-year-old Japanese man was admitted with a 4-month history of fatigue and exertional dyspnea. Transthoracic echocardiography revealed a vegetation on the aortic valve and severe aortic regurgitation. Accordingly, infective endocarditis and heart failure were diagnosed. Although a blood culture was negative on day 7 after admission, a prolonged blood culture with subculture was performed according to the patient's history of contact with cats. Consequently, Bartonella henselae was isolated. Bartonella species are fastidious bacteria that cause blood culture-negative infective endocarditis. This case demonstrates that B. henselae may be detected by prolonged incubation of blood cultures.

  16. Bartonella henselae Infective Endocarditis Detected by a Prolonged Blood Culture

    PubMed Central

    Mito, Tsutomu; Hirota, Yusuke; Suzuki, Shingo; Noda, Kazutaka; Uehara, Takanori; Ohira, Yoshiyuki; Ikusaka, Masatomi

    2016-01-01

    A 65-year-old Japanese man was admitted with a 4-month history of fatigue and exertional dyspnea. Transthoracic echocardiography revealed a vegetation on the aortic valve and severe aortic regurgitation. Accordingly, infective endocarditis and heart failure were diagnosed. Although a blood culture was negative on day 7 after admission, a prolonged blood culture with subculture was performed according to the patient's history of contact with cats. Consequently, Bartonella henselae was isolated. Bartonella species are fastidious bacteria that cause blood culture-negative infective endocarditis. This case demonstrates that B. henselae may be detected by prolonged incubation of blood cultures. PMID:27746451

  17. Changes in the human blood coagulating system during prolonged hypokinesia

    NASA Technical Reports Server (NTRS)

    Filatova, L. M.; Anashkin, O. D.

    1978-01-01

    Changes in the coagulating system of the blood were studied in six subjects during prolonged hypokinesia. Thrombogenic properties of the blood rose in all cases on the 8th day. These changes are explained by stress reaction due to unusual conditions for a healthy person. Changes in the blood coagulating system in the group subjected to physical exercise and without it ran a practically parallel course. Apparently physical exercise is insufficient to prevent such changes that appear in the coagulating system of the blood during prolonged hypokinesia.

  18. Plasma cell-free mitochondrial DNA declines in response to prolonged moderate aerobic exercise.

    PubMed

    Shockett, Penny E; Khanal, Januka; Sitaula, Alina; Oglesby, Christopher; Meachum, William A; Castracane, V Daniel; Kraemer, Robert R

    2016-01-01

    Increased plasma cell-free mitochondrial DNA (cf-mDNA), a damage-associated molecular pattern (DAMP) produced by cellular injury, contributes to neutrophil activation/inflammation in trauma patients and arises in cancer and autoimmunity. To further understand relationships between cf-mDNA released by tissue injury, inflammation, and health benefits of exercise, we examined cf-mDNA response to prolonged moderate aerobic exercise. Seven healthy moderately trained young men (age = 22.4 ± 1.2) completed a treadmill exercise trial for 90 min at 60% VO2 max and a resting control trial. Blood was sampled immediately prior to exercise (0 min = baseline), during (+18, +54 min), immediately after (+90 min), and after recovery (R40). Plasma was analyzed for cf-mDNA, IL-6, and lactate. A significant difference in cf-mDNA response was observed between exercise and control trials, with cf-mDNA levels reduced during exercise at +54 and +90 (with or without plasma volume shift correction). Declines in cf-mDNA were accompanied by increased lactate and followed by an increase in IL-6, suggesting a temporal association with muscle stress and inflammatory processes. Our novel finding of cf-mDNA decline with prolonged moderate treadmill exercise provides evidence for increased clearance from or reduced release of cf-mDNA into the blood with prolonged exercise. These studies contrast with previous investigations involving exhaustive short-term treadmill exercise, in which no change in cf-mDNA levels were reported, and contribute to our understanding of differences between exercise- and trauma-induced inflammation. We propose that transient declines in cf-mDNA may induce health benefits, by reducing systemic inflammation.

  19. Fitness benefits of prolonged post-reproductive lifespan in women.

    PubMed

    Lahdenperä, Mirkka; Lummaa, Virpi; Helle, Samuli; Tremblay, Marc; Russell, Andrew F

    2004-03-11

    Most animals reproduce until they die, but in humans, females can survive long after ceasing reproduction. In theory, a prolonged post-reproductive lifespan will evolve when females can gain greater fitness by increasing the success of their offspring than by continuing to breed themselves. Although reproductive success is known to decline in old age, it is unknown whether women gain fitness by prolonging lifespan post-reproduction. Using complete multi-generational demographic records, we show that women with a prolonged post-reproductive lifespan have more grandchildren, and hence greater fitness, in pre-modern populations of both Finns and Canadians. This fitness benefit arises because post-reproductive mothers enhance the lifetime reproductive success of their offspring by allowing them to breed earlier, more frequently and more successfully. Finally, the fitness benefits of prolonged lifespan diminish as the reproductive output of offspring declines. This suggests that in female humans, selection for deferred ageing should wane when one's own offspring become post-reproductive and, correspondingly, we show that rates of female mortality accelerate as their offspring terminate reproduction.

  20. Diet-consumer nitrogen isotope fractionation for prolonged fasting arthropods.

    PubMed

    Mizota, Chitoshi; Yamanaka, Toshiro

    2011-12-01

    Nitrogen acquisition for cellular metabolism during diapause is a primary concern for herbivorous arthropods. Analyses of naturally occurring stable isotopes of nitrogen help elucidate the mechanism. Relevant articles have cited (58 times up to mid-June 2011) anomalously elevated δ(15)N (per mil deviation of (15)N/(14)N, relative to atmospheric nitrogen=0 ‰) values (diet-consumer nitrogen isotope fractionation; up to 12 ‰) for a prolonged fasting raspberry beetle (Byturus tomentosus Degeer (Coleoptera: Byturidae)), which feeds on red raspberries (Rubus idaeus: δ(15)N= ~ +2 ‰). Biologists have hypothesised that extensive recycling of amino acid nitrogen is responsible for the prolonged fasting. Since this hypothesis was proposed in 1995, scientists have integrated biochemical and molecular knowledge to support the mechanism of prolonged diapausing of animals. To test the validity of the recycling hypothesis, we analysed tissue nitrogen isotope ratios for four Japanese arthropods: the shield bug Parastrachia japonensis Scott (Hemiptera: Cydnidae), the burrower bug Canthophorus niveimarginatus Scott (Hemiptera: Cydnidae), leaf beetle Gastrophysa atrocyanea Motschulsky (Coleoptera: Chrysomelidae) and the Japanese oak silkworm Antheraea yamamai (Lepidoptera: Saturniidae), all of which fast for more than 6 months as part of their life-history strategy. Resulting diet-consumer nitrogen isotope discrimination during fasting ranged from 0 to 7‰, as in many commonly known terrestrial arthropods. We conclude that prolonged fasting of arthropods does not always result in anomalous diet-consumer nitrogen isotope fractionation, since the recycling process is closed or nearly closed with respect to nitrogen isotopes.

  1. Economic viability of beef cattle grazing systems under prolonged drought

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prolonged drought in the Southern Great Plains of the USA in recent years has raised concerns about vulnerability of beef cattle grazing systems under adverse climate change. To help address the economic viability of beef grazing operations in the Southern Great Plains, this paper provides an econom...

  2. Long term cognitive development in children with prolonged crying

    PubMed Central

    Rao, M; Brenner, R; Schisterman, E; Vik, T; Mills, J

    2004-01-01

    Background: Long term studies of cognitive development and colic have not differentiated between typical colic and prolonged crying. Objective: To evaluate whether colic and excessive crying that persists beyond 3 months is associated with adverse cognitive development. Design: Prospective cohort study. A sample of 561 women was enrolled in the second trimester of pregnancy. Colic and prolonged crying were based on crying behaviour assessed at 6 and 13 weeks. Children's intelligence, motor abilities, and behaviour were measured at 5 years (n = 327). Known risk factors for cognitive impairment were ascertained prenatally, after birth, at 6 and 13 weeks, at 6, 9, and 13 months, and at 5 years of age. Results: Children with prolonged crying (but not those with colic only) had an adjusted mean IQ that was 9 points lower than the control group. Their performance and verbal IQ scores were 9.2 and 6.7 points lower than the control group, respectively. The prolonged crying group also had significantly poorer fine motor abilities compared with the control group. Colic had no effect on cognitive development. Conclusions: Excessive, uncontrolled crying that persists beyond 3 months of age in infants without other signs of neurological damage may be a marker for cognitive deficits during childhood. Such infants need to be examined and followed up more intensively. PMID:15499048

  3. Delirium in Prolonged Hospitalized Patients in the Intensive Care Unit

    PubMed Central

    Vahedian Azimi, Amir; Ebadi, Abbas; Ahmadi, Fazlollah; Saadat, Soheil

    2015-01-01

    Background: Prolonged hospitalization in the intensive care unit (ICU) can impose long-term psychological effects on patients. One of the most significant psychological effects from prolonged hospitalization is delirium. Objectives: The aim of this study was to assess the effect of prolonged hospitalization of patients and subsequent delirium in the intensive care unit. Patients and Methods: This conventional content analysis study was conducted in the General Intensive Care Unit of the Shariati Hospital of Tehran University of Medical Sciences, from the beginning of 2013 to 2014. All prolonged hospitalized patients and their families were eligible participants. From the 34 eligible patients and 63 family members, the final numbers of actual patients and family members were 9 and 16, respectively. Several semi-structured interviews were conducted face-to-face with patients and their families in a private room and data were gathered. Results: Two main themes from two different perspectives emerged, 'patients' perspectives' (experiences during ICU hospitalization) and 'family members' perspectives' (supportive-communicational experiences). The main results of this study focused on delirium, Patients' findings were described as pleasant and unpleasant, factual and delusional experiences. Conclusions: Family members are valuable components in the therapeutic process of delirium. Effective use of family members in the delirium caring process can be considered to be one of the key non-medical nursing components in the therapeutic process. PMID:26290854

  4. Metabolic and Cardiovascular Responses of Children during Prolonged Physical Activity.

    ERIC Educational Resources Information Center

    Chausow, Sharon A.; And Others

    1984-01-01

    Metabolic and cardiovascular responses during 45 minutes of continuous moderate intensity exercise were investigated in 11 children, 8-11 years of age. Results indicate that children exhibit metabolic and cardiovascular adjustments similar to those noted in adults during prolonged exercise. (Author/JMK)

  5. Frequency and cause of transient QT prolongation after surgery.

    PubMed

    Joyce, Daniel D; Bos, J Martijn; Haugaa, Kristina H; Tarrell, Robert F; Morlan, Bruce W; Caraballo, Pedro J; Ackerman, Michael J

    2015-11-15

    Patients undergoing surgery are often exposed to QT-inciting factors that may increase the risk for complications. We evaluated the clinical characteristics and outcomes of patients with QTc ≥500 ms within the first 24 hours after surgery as identified by an institution-wide electrocardiogram alert system. From November 2010 to June 2011, 470 patients exhibited an electrocardiographically isolated QTc ≥500 ms. QT prolongation after surgery was the setting for >1 of every 10 QTc alerts (59 patients). We determined the presence of QT prolonging medical conditions, drugs, electrolyte abnormalities, and the surgical patient's clinical outcome. The average preoperative QTc of the 59 patients demonstrating perioperative QT prolongation was 463 ± 56 ms with a postoperative QTc increase of 54 ± 37 ms. Most patients (n = 48, 83%) had ≥1 known QT-inciting factor before surgery. Compared with presurgical findings, there was a significant increase in pro-QTc score after surgery (1.8 ± 1.5 vs 3.5 ± 2.0, p <0.01) indicating a greater burden of perioperative QT-inciting factors. In conclusion, nearly all cases of QT prolongation could be explained by known etiologic or iatrogenic factors suggesting that maladaptive cardiac repolarization is most likely not a transient, postoperative stress response and may be avoided by altering clinical management.

  6. Preferences for Prolonging Life: A Prospect Theory Approach

    ERIC Educational Resources Information Center

    Winter, Laraine; Lawton, M. Powell; Ruckdeschel, Katy

    2003-01-01

    Kahneman and Tversky's (1979) Prospect theory was tested as a model of preferences for prolonging life under various hypothetical health statuses. A sample of 384 elderly people living in congregate housing (263 healthy, 131 frail) indicated how long (if at all) they would want to live under each of nine hypothetical health conditions (e.g.,…

  7. Family presence during cardiopulmonary resuscitation: grief therapy or prolonged futility?

    PubMed

    Sherman, David A

    2008-01-01

    Nursing leaders are responsible in part for implementing procedures supporting family presence during cardiopulmonary resuscitation. Family presence has received broad support in nursing literature and from professional organizations. A case study suggests that, when a patient's spokesperson is struggling with the question of whether to set limits to treatments, allowing family presence may inappropriately prolong futile care.

  8. Effect of prolonged bed rest on the anterior hip muscles.

    PubMed

    Dilani Mendis, M; Hides, Julie A; Wilson, Stephen J; Grimaldi, Alison; Belavý, Daniel L; Stanton, Warren; Felsenberg, Dieter; Rittweger, Joern; Richardson, Carolyn

    2009-11-01

    Prolonged bed rest and inactivity is known to cause muscular atrophy with previous research indicating that muscles involved in joint stabilisation are more susceptible. The anterior hip muscles are important for hip joint function and stability but little is known about the effects of prolonged inactivity on their function. This study investigated the effect of prolonged bed rest on the size of the anterior hip muscles and their pattern of recovery. The effect of resistive vibration exercise (RVE) as a countermeasure to muscle atrophy was also investigated. 12 male participants, randomly assigned to either a control or an exercise group, underwent 8 weeks of bed rest with 6 months follow-up. Changes in muscle cross-sectional area (CSA) of the iliacus, psoas, iliopsoas, sartorius and rectus femoris muscles were measured by magnetic resonance imaging at regular intervals during bed rest and recovery phases. CSAs of iliopsoas and sartorius decreased at the hip joint (p<0.05) during bed rest but iliacus, psoas, and rectus femoris CSAs were unchanged (p>0.05). No significant difference was found between the two groups for all muscles (all p>0.1), suggesting inefficacy of the countermeasure in this sample. These findings suggest that prolonged bed rest can result in the atrophy of specific muscles across the hip joint which may affect its stability and function.

  9. Prolonged idiopathic gastric dilatation following revascularization for chronic mesenteric ischemia.

    PubMed

    Gauci, Julia L; Stoven, Samantha; Szarka, Lawrence; Papadakis, Konstantinos A

    2014-01-01

    A 71-year-old female presented with nausea, emesis, early satiety, and abdominal distension following revascularization for chronic mesenteric ischemia. Computed tomography angiogram showed gastric dilatation. Esophagogastroduodenoscopy, small bowel follow through, and paraneoplastic panel were negative. Gastric emptying was delayed. Despite conservative management, she required a percutaneous endoscopic jejunostomy. The development of a prolonged gastroparetic state has not been previously described.

  10. Recognition Memory Is Impaired in Children after Prolonged Febrile Seizures

    ERIC Educational Resources Information Center

    Martinos, Marina M.; Yoong, Michael; Patil, Shekhar; Chin, Richard F. M.; Neville, Brian G.; Scott, Rod C.; de Haan, Michelle

    2012-01-01

    Children with a history of a prolonged febrile seizure show signs of acute hippocampal injury on magnetic resonance imaging. In addition, animal studies have shown that adult rats who suffered febrile seizures during development reveal memory impairments. Together, these lines of evidence suggest that memory impairments related to hippocampal…

  11. Single Prolonged Stress Disrupts Retention of Extinguished Fear in Rats

    ERIC Educational Resources Information Center

    Knox, Dayan; George, Sophie A.; Fitzpatrick, Christopher J.; Rabinak, Christine A.; Maren, Stephen; Liberzon, Israel

    2012-01-01

    Clinical research has linked post-traumatic stress disorder (PTSD) with deficits in fear extinction. However, it is not clear whether these deficits result from stress-related changes in the acquisition or retention of extinction or in the regulation of extinction memories by context, for example. In this study, we used the single prolonged stress…

  12. Prolonged-release melatonin for children with neurodevelopmental disorders.

    PubMed

    De Leersnyder, Hélène; Zisapel, Nava; Laudon, Moshe

    2011-07-01

    Previous studies demonstrated the efficacy and safety of prolonged-release melatonin in children and adolescents with neurodevelopmental and behavioral disorders. The long-term effectiveness and safety of prolonged-release melatonin treatment were assessed in 88 children (42 girls and 46 boys) with neurodevelopmental disorders. These patients participated in a compassionate-use program with the drug Circadin (2 mg; Neurim Pharmaceuticals, Tel Aviv, Israel) in France, and received treatment in the context of regular care by a specialized physician. The study involved a structured questionnaire for the parents, comprising a combination of multiple-choice and numeric questions addressing sleep onset/offset, sleep quality problems, and mood. The dose of melatonin ranged from 4-6 mg, and treatment duration ranged from 6-72 months. Within 3 months, sleep latency with prolonged-release melatonin decreased by 44.0% (P < 0.001), sleep duration increased by 10.1% (P < 0.001), the number of awakenings decreased by 75% (P < 0.001), and sleep quality improved by 75%, compared with baseline (P < 0.001). No serious adverse events or treatment-related comorbidities were reported. Prolonged-release melatonin remains a safe, effective therapy for the long-term treatment of sleep disorders in children with neurodevelopmental disorders.

  13. Intrinsic motivation and amotivation in first episode and prolonged psychosis.

    PubMed

    Luther, Lauren; Lysaker, Paul H; Firmin, Ruth L; Breier, Alan; Vohs, Jenifer L

    2015-12-01

    The deleterious functional implications of motivation deficits in psychosis have generated interest in examining dimensions of the construct. However, there remains a paucity of data regarding whether dimensions of motivation differ over the course of psychosis. Therefore, this study examined two motivation dimensions, trait-like intrinsic motivation, and the negative symptom of amotivation, and tested the impact of illness phase on the 1) levels of these dimensions and 2) relationship between these dimensions. Participants with first episode psychosis (FEP; n=40) and prolonged psychosis (n=66) completed clinician-rated measures of intrinsic motivation and amotivation. Analyses revealed that when controlling for group differences in gender and education, the FEP group had significantly more intrinsic motivation and lower amotivation than the prolonged psychosis group. Moreover, intrinsic motivation was negatively correlated with amotivation in both FEP and prolonged psychosis, but the magnitude of the relationship did not statistically differ between groups. These findings suggest that motivation deficits are more severe later in the course of psychosis and that low intrinsic motivation may be partially independent of amotivation in both first episode and prolonged psychosis. Clinically, these results highlight the importance of targeting motivation in early intervention services.

  14. Prolonged unassisted survival in an infant with anencephaly.

    PubMed

    Dickman, Holly; Fletke, Kyle; Redfern, Roberta E

    2016-10-31

    Anencephaly is one of the most lethal congenital defects. This case report is of an anencephalic infant who lived to 28 months of life and defies current literature. She is the longest surviving anencephalic infant who did not require life-sustaining interventions. This case presents the obstacles that arose from this infant's prolonged life and recommendations based on these findings.

  15. Efficacy of an Emotion-Focused Treatment for Prolonged Fatigue

    ERIC Educational Resources Information Center

    Schutte, Nicola S.; Malouff, John M.; Brown, Rhonda F.

    2008-01-01

    Previous research findings have suggested a relationship between less adaptive emotional functioning and fatigue. The present study used a research design involving multiple baselines across participants to evaluate the efficacy of a new emotion-focused treatment for prolonged fatigue delivered in a cognitive behavioral therapy framework. The 13…

  16. Technologies for Prolonging Cardiac Implantable Electronic Device Longevity.

    PubMed

    Lau, Ernest W

    2017-01-01

    Prolonged longevity of cardiac implantable electronic devices (CIEDs) is needed not only as a passive response to match the prolonging life expectancy of patient recipients, but will also actively prolong their life expectancy by avoiding/deferring the risks (and costs) associated with device replacement. CIEDs are still exclusively powered by nonrechargeable primary batteries, and energy exhaustion is the dominant and an inevitable cause of device replacement. The longevity of a CIED is thus determined by the attrition rate of its finite energy reserve. The energy available from a battery depends on its capacity (total amount of electric charge), chemistry (anode, cathode, and electrolyte), and internal architecture (stacked plate, folded plate, and spiral wound). The energy uses of a CIED vary and include a background current for running electronic circuitry, periodic radiofrequency telemetry, high-voltage capacitor reformation, constant ventricular pacing, and sporadic shocks for the cardiac resynchronization therapy defibrillators. The energy use by a CIED is primarily determined by the patient recipient's clinical needs, but the energy stored in the device battery is entirely under the manufacturer's control. A larger battery capacity generally results in a longer-lasting device, but improved battery chemistry and architecture may allow more space-efficient designs. Armed with the necessary technical knowledge, healthcare professionals and purchasers will be empowered to make judicious selection on device models and maximize the utilization of all their energy-saving features, to prolong device longevity for the benefits of their patients and healthcare systems.

  17. Causes of Death Associated With Prolonged TV Viewing

    PubMed Central

    Keadle, Sarah K.; Moore, Steven C.; Sampson, Joshua N.; Xiao, Qian; Albanes, Demetrius; Matthews, Charles E.

    2015-01-01

    Introduction TV viewing is the most prevalent sedentary behavior and is associated with increased risk of cardiovascular disease and cancer mortality, but the association with other leading causes of death is unknown. This study examined the association between TV viewing and leading causes of death in the U.S. Methods A prospective cohort of 221,426 individuals (57% male) aged 50–71 years who were free of chronic disease at baseline (1995–1996), 93% white, with an average BMI of 26.7 (SD=4.4) kg/m2 were included. Participants self-reported TV viewing at baseline and were followed until death or December 31, 2011. Hazard ratios (HRs) and 95% CIs for TV viewing and cause-specific mortality were estimated using Cox proportional hazards regression. Analyses were conducted in 2014–2015. Results After an average follow-up of 14.1 years, adjusted mortality risk for a 2-hour/day increase in TV viewing was significantly higher for the following causes of death (HR [95% CI]): cancer (1.07 [1.03, 1.11); heart disease (1.23 [1.17, 1.29]); chronic obstructive pulmonary disease (1.28 [1.14, 1.43]); diabetes (1.56 [1.33, 1.83]); influenza/pneumonia (1.24 [1.02, 1.50]); Parkinson disease (1.35 [1.11, 1.65]); liver disease (1.33 [1.05, 1.67]); and suicide (1.43 [1.10, 1.85]. Mortality associations persisted in stratified analyses with important potential confounders, reducing causation concerns. Conclusions This study shows the breadth of mortality outcomes associated with prolonged TV viewing, and identifies novel associations for several leading causes of death. TV viewing is a prevalent discretionary behavior that may be a more important target for public health intervention than previously recognized. Trial Registration ClinicalTrials.gov number, NCT00340015 PMID:26215832

  18. Prolonged neuromuscular block in a preeclamptic patient induced by magnesium sulfate

    PubMed Central

    Berdai, Mohamed Adnane; Labib, Smael; Harandou, Mustapha

    2016-01-01

    Recent large use of magnesium in the obstetric population should incite anesthesiologists to control its side effects and drugs interactions. We report a case of a 30-year-old woman, with severe preeclampsia and HELLP syndrome, receiving sulfate magnesium and nicardipine, who underwent a cesarean section under general anesthesia. She developed a prolonged and deep neuromuscular blockade, which was antagonized three hours later with neostigmine. In case of therapeutic hypermagnesaemia, non-depolarizing relaxants must be used in reduced doses, and at increased time intervals, with appropriate neuromuscular monitoring. PMID:28154698

  19. Prolonging Survival of Corneal Transplantation by Selective Sphingosine-1-Phosphate Receptor 1 Agonist

    PubMed Central

    Gao, Min; Liu, Yong; Xiao, Yang; Han, Gencheng; Jia, Liang; Wang, Liqiang; Lei, Tian; Huang, Yifei

    2014-01-01

    Corneal transplantation is the most used therapy for eye disorders. Although the cornea is somewhat an immune privileged organ, immune rejection is still the major problem that reduces the success rate. Therefore, effective chemical drugs that regulate immunoreactions are needed to improve the outcome of corneal transplantations. Here, a sphingosine-1-phosphate receptor 1 (S1P1) selective agonist was systematically evaluated in mouse allogeneic corneal transplantation and compared with the commonly used immunosuppressive agents. Compared with CsA and the non-selective sphingosine 1-phosphate (S1P) receptor agonist FTY720, the S1P1 selective agonist can prolong the survival corneal transplantation for more than 30 days with a low immune response. More importantly, the optimal dose of the S1P1 selective agonist was much less than non-selective S1P receptor agonist FTY720, which would reduce the dose-dependent toxicity in drug application. Then we analyzed the mechanisms of the selected S1P1 selective agonist on the immunosuppression. The results shown that the S1P1 selective agonist could regulate the distribution of the immune cells with less CD4+ T cells and enhanced Treg cells in the allograft, moreover the expression of anti-inflammatory cytokines TGF-β1 and IL-10 unregulated which can reduce the immunoreactions. These findings suggest that S1P1 selective agonist may be a more appropriate immunosuppressive compound to effectively prolong mouse allogeneic corneal grafts survival. PMID:25216235

  20. Prolonged patient emergence time among clinical anesthesia resident trainees

    PubMed Central

    House, L. McLean; Calloway, Nathan H.; Sandberg, Warren S.; Ehrenfeld, Jesse M.

    2016-01-01

    Background and Aims: Emergence time, or the duration between incision closure and extubation, is costly nonoperative time. Efforts to improve operating room efficiency and identify trainee progress make such time intervals of interest. We sought to calculate the incidence of prolonged emergence (i.e., >15 min) for patients under the care of clinical anesthesia (CA) residents. We also sought to identify factors from resident training, medical history, anesthetic use, and anesthesia staffing, which affect emergence. Material and Methods: In this single-center, historical cohort study, perioperative information management systems provided data for surgical cases under resident care at a tertiary care center in the United States from 2006 to 2008. Using multiple logistic regression, the effects of variables on emergence was analyzed. Results: Of 7687 cases under the care of 27 residents, the incidence of prolonged emergence was 13.9%. Emergence prolongation decreased by month in training for 1st-year (CA-1) residents (r2 = 0.7, P < 0.001), but not for CA-2 and CA-3 residents. Mean patient emergence time differed among 27 residents (P < 0.01 for 58.4% or 205/351 paired comparisons). In a model restricted to 1st-year residents, patient male gender, American Society of Anesthesiologists (ASA) physical status >II, emergency surgical case, operative duration ≥2 h, and paralytic agent use were associated with higher frequency of prolonged emergence, while sevoflurane or desflurane use was associated with lower frequency. Attending anesthesiologist handoff was not associated with longer emergence. Conclusion: Incidence of prolonged emergence from general anesthesia differed significantly among trainees, by resident training duration, and for patients with ASA >II. PMID:28096573

  1. Use of in vitro methods to predict QT prolongation

    SciTech Connect

    Hammond, T.G. . E-mail: tim.hammond@astrazeneca.com; Pollard, C.E.

    2005-09-01

    The inhibition of the hERG-encoded potassium channel can lead to prolongation of the cardiac action potential-manifested as a prolongation of the QT interval on the ECG. Although QT interval prolongation is not dangerous per se, in a small percentage of cases, it is associated with a potentially fatal arrhythmia: Torsades de Pointes (TdP). This channel type is pharmacologically promiscuous, so many compounds have caused QT interval prolongation in man and this has led to drugs being withdrawn from the market following evidence of TdP. From a drug discovery perspective, focusing as early as possible on screening out hERG activity is important. Retrospective analysis of hERG potency versus clinical incidence of TdP suggests provisional safety margins that could be used as target values by medicinal chemists. Large safety margins will not always be possible; however, and in such circumstances, if the risk-benefit ratio still favours developing the compound, a pre-clinical assessment of the likelihood that any QT interval prolongation will or will not lead to TdP in man may be important. An isolated rabbit heart model of arrhythmia shows promise in this respect, based on a comparison of clinical data with that obtained from this assay. Specific regulatory guidance on this topic is still in the draft form but the pre-clinical document (ICH S7B) contains a largely useful perspective on how an integrated risk assessment could be formed using in vitro and in vivo assays. The role of this document is evolving however, since the draft clinical guideline (E14) suggests that irrespective of the pre-clinical data, a thorough clinical ECG study will be required at some point during development.

  2. Relationship between brief and prolonged repeated sprint ability.

    PubMed

    Oliver, Jonathan L; Armstrong, Neil; Williams, Craig A

    2009-01-01

    Repeated sprint ability (RSA) is often assessed over a brief time period with limited recovery between sprints; however, it is not known how performance in such tests is related to the ability to perform repeated sprints over a more prolonged duration. Eighteen boys aged 15.3+/-0.5 years completed both a brief and prolonged RSA test on a non-motorised treadmill. The brief RSA test consisted of seven 5s sprints with 20s of recovery between sprints and the prolonged RSA test lasted for 42min and included a 5s sprint every 2min. There was a moderate but significant relationship between the mean speed in both tests (r=0.51, p<0.05). The maximal speed achieved in a single sprint provided strong relationships with both brief RSA speed (r> or =0.72, p<0.001) and prolonged RSA speed (r> or =0.77, p<0.001). Total work done during the brief protocol was significantly correlated to both total work (r=0.81, p<0.001) and total sprint distance (r=0.79, p<0.001) during the prolonged test. There were no significant relationships between percentage decrement scores across the two protocols (r< or =0.33, p>0.05). Maximal speed in a single sprint and total work done during repeated sprints represent general qualities related to RSA that are independent of the test protocol. The mean speed and decrements in performance represent specific RSA qualities, which are dependent on the frequency of sprints and duration of the test protocol.

  3. Diagnostic and clinical considerations in prolonged grief disorder

    PubMed Central

    Maercker, Andreas; Lalor, John

    2012-01-01

    This review focuses on the similarities and differences between prolonged grief disorder (PGD) and post-traumatic stress disorder (PTSD). It highlights how a PTSD-related understanding aids the investigation and clinical management of PGD. Grief has long been understood as a natural response to bereavement, as serious psychological and physiological stress has been regarded as a potential outcome of extreme or traumatic stress. PTSD was first included in DSM-III in 1980. In the mid-1980s, the first systematic investigation began into whether there is an extreme or pathological form of mourning. Meanwhile, there is much research literature on complicated, traumatic, or prolonged grief This literature is reviewed in this article, with the following questions: Is it possible to distinguish normal from non-normal grief? Which clinical presentation does PGD have—and how does this compare with PTSD? Finally, diagnostic, preventive, and therapeutic approaches and existing tools are presented. PMID:22754289

  4. Prolonged Remission in Neuromyelitis Optica Following Cessation of Rituximab Treatment.

    PubMed

    Weinfurtner, Kelley; Graves, Jennifer; Ness, Jayne; Krupp, Lauren; Milazzo, Maria; Waubant, Emmanuelle

    2015-09-01

    Neuromyelitis optica is an autoimmune disease characterized by acute episodes of transverse myelitis and optic neuritis. Several small, open-label studies suggest rituximab, a monoclonal antibody against CD20, prevents relapses in neuromyelitis optica; however, there is little consensus on timing or duration of treatment. Here we report four patients with severe relapsing neuromyelitis optica who were stabilized on rituximab and, after discontinuing treatment, continued to experience prolonged remission of their disease. Remission ranged from 4.5 to 10.5 years total, including 3 to 9 years off all therapies. The patients had sustained clinical responses despite normal B-lymphocyte levels and, in at least 2 patients, continued seropositivity for aquaporin-4 antibodies. These cases suggest that rituximab may induce prolonged remission in certain neuromyelitis optica patients, and they highlight the need for further elucidation of rituximab's mechanism in neuromyelitis optica.

  5. Prolonged and tunable residence time using reversible covalent kinase inhibitors

    PubMed Central

    Bradshaw, J. Michael; McFarland, Jesse M.; Paavilainen, Ville O.; Bisconte, Angelina; Tam, Danny; Phan, Vernon T.; Romanov, Sergei; Finkle, David; Shu, Jin; Patel, Vaishali; Ton, Tony; Li, Xiaoyan; Loughhead, David G.; Nunn, Philip A.; Karr, Dane E.; Gerritsen, Mary E.; Funk, Jens Oliver; Owens, Timothy D.; Verner, Erik; Brameld, Ken A.; Hill, Ronald J.; Goldstein, David M.; Taunton, Jack

    2015-01-01

    Drugs with prolonged, on-target residence time often show superior efficacy, yet general strategies for optimizing drug-target residence time are lacking. Here, we demonstrate progress toward this elusive goal by targeting a noncatalytic cysteine in Bruton's tyrosine kinase (BTK) with reversible covalent inhibitors. Utilizing an inverted orientation of the cysteine-reactive cyanoacrylamide electrophile, we identified potent and selective BTK inhibitors that demonstrate biochemical residence times spanning from minutes to 7 days. An inverted cyanoacrylamide with prolonged residence time in vivo remained bound to BTK more than 18 hours after clearance from the circulation. The inverted cyanoacrylamide strategy was further utilized to discover fibroblast growth factor receptor (FGFR) kinase inhibitors with residence times of several days, demonstrating generalizability of the approach. Targeting noncatalytic cysteines with inverted cyanoacrylamides may serve as a broadly applicable platform that facilitates “residence time by design”, the ability to modulate and improve the duration of target engagement in vivo. PMID:26006010

  6. Is prolonged and excessive cooling of a scalded wound effective?

    PubMed

    Sawada, Y; Urushidate, S; Yotsuyanagi, T; Ishita, K

    1997-02-01

    An experimental study was carried out using rats to evaluate the effectiveness of prolonged and excessive cooling on the burned wound just immediately after injury. The wound was produced by applying a lint immersed in boiled water at 99 degrees C. The wound produced by applying a lint for 3 s, and then immediately soaking with tap water for 1 min, resulted in little damage. However, the wound produced by applying a lint for 10 s, and immediately after an ice cube applied for 10 min, resulted in the most severe damage. The wound produced by applying a lint for 10 s, and no treatment applied thereafter, and the wound produced by applying a lint for 10 s and immediately after soaked with tap water for 1 min, resulted in moderate damage. From this experiment, it is suggested excessive and prolonged cooling of the burn wound, such as using an ice cube immediately after injury, is harmful in some instances.

  7. Infection prevention and control during prolonged human space travel.

    PubMed

    Mermel, Leonard A

    2013-01-01

    Prolonged human spaceflight to another planet or an asteroid will introduce unique challenges of mitigating the risk of infection. During space travel, exposure to microgravity, radiation, and stress alter human immunoregulatory responses, which can in turn impact an astronaut's ability to prevent acquisition of infectious agents or reactivation of latent infection. In addition, microgravity affects virulence, growth kinetics, and biofilm formation of potential microbial pathogens. These interactions occur in a confined space in microgravity, providing ample opportunity for heavy microbial contamination of the environment. In addition, there is the persistence of aerosolized, microbe-containing particles. Any mission involving prolonged human spaceflight must be carefully planned to minimize vulnerabilities and maximize the likelihood of success.

  8. Silencing microRNA-134 produces neuroprotective and prolonged seizure-suppressive effects

    PubMed Central

    Jimenez-Mateos, Eva M.; Engel, Tobias; Merino-Serrais, Paula; McKiernan, Ross C.; Tanaka, Katsuhiro; Mouri, Genshin; Sano, Takanori; O’Tuathaigh, Colm; Waddington, John L.; Prenter, Suzanne; Delanty, Norman; Farrell, Michael A.; O’Brien, Donncha F.; Conroy, Ronán M.; Stallings, Raymond L.; deFelipe, Javier; Henshall, David C.

    2012-01-01

    Temporal lobe epilepsy is a common, chronic neurologic disorder characterized by recurrent spontaneous seizures. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate post-transcriptional expression of protein-coding mRNAs, which may have important roles in the pathogenesis of neurologic disorders. In models of prolonged, injurious seizures (status epilepticus) and in experimental and human epilepsy, we found up-regulation of miR-134, a brain-specific, activity-regulated miRNA implicated in the control of dendritic spine morphology. Silencing of miR-134 expression in vivo using antagomirs reduced hippocampal CA3 pyramidal neuron dendrite spine density by 21%, and rendered mice refractory to seizures and hippocampal injury caused by status epilepticus. Depletion of miR-134 after status epilepticus reduced the later occurrence of spontaneous seizures by over 90% and mitigated attendant pathologic features of temporal lobe epilepsy. Thus, silencing miR-134 exerts prolonged seizure suppressant and neuroprotective actions; whether these represent anticonvulsant or truly antiepileptogenic effects requires additional experimentation. PMID:22683779

  9. A Parallelized Pumpless Artificial Placenta System Significantly Prolonged Survival Time in a Preterm Lamb Model.

    PubMed

    Miura, Yuichiro; Matsuda, Tadashi; Usuda, Haruo; Watanabe, Shimpei; Kitanishi, Ryuta; Saito, Masatoshi; Hanita, Takushi; Kobayashi, Yoshiyasu

    2016-05-01

    An artificial placenta (AP) is an arterio-venous extracorporeal life support system that is connected to the fetal circulation via the umbilical vasculature. Previously, we published an article describing a pumpless AP system with a small priming volume. We subsequently developed a parallelized system, hypothesizing that the reduced circuit resistance conveyed by this modification would enable healthy fetal survival time to be prolonged. We conducted experiments using a premature lamb model to test this hypothesis. As a result, the fetal survival period was significantly prolonged (60.4 ± 3.8 vs. 18.2 ± 3.2 h, P < 0.01), and circuit resistance and minimal blood lactate levels were significantly lower in the parallel circuit group, compared with our previous single circuit group. Fetal physiological parameters remained stable until the conclusion of the experiments. In summary, parallelization of the AP system was associated with reduced circuit resistance and lactate levels and allowed preterm lamb fetuses to survive for a significantly longer period when compared with previous studies.

  10. Hormone supply of the organism in prolonged emotional stress

    NASA Technical Reports Server (NTRS)

    Amiragova, M. G.; Stulnikov, B. V.; Svirskaya, R. I.

    1980-01-01

    The effect of prolonged emotional stress of varying genesis on the hormonal function of the pancreas, thyroid gland, and adrenal cortex was studied. The amount of the hormonal secretion was found to depend on the type of adaptation activity and its duration. High secretion of the hormones observed outside the adaptation activity was examined as an index of the phase transition of defense reactions to the phase of overstress.

  11. A Case of QT Prolongation Associated with Panhypopituitarism

    PubMed Central

    Garip, Tayfun; Tamer, Ali

    2013-01-01

    We describe a 37-year-old patient with panhypopituitarism who experienced symptoms and signs of hormonal insufficiency and QT prolongation on electrocardiogram without electrolyte disturbances. After hormonal (steroidal and thyroid) replacement therapy electrocardiographic findings were normalized. Hormonal disorders should be considered as a cause of long QT intervals which may lead to torsade de pointes, even if plasma electrolyte levels are normal, because life-threatening arrhythmia is treatable by supplementation of the hormone that is lacking. PMID:23762665

  12. Slow recovery in desert perennial vegetation following prolonged human disturbance

    USGS Publications Warehouse

    Guo, Q.

    2004-01-01

    Questions: How long may it take for desert perennial vegetation to recover from prolonged human disturbance and how do different plant community variables (i.e. diversity, density and cover) change during the recovery process? Location: Sonoran Desert, Arizona, USA. Methods: Since protection from grazing from 1907 onwards, plant diversity, density and cover of perennial species were monitored intermittently on ten 10 m x 10 m permanent plots on Tumamoc Hill, Tucson, Arizona, USA. Results: The study shows an exceptionally slow recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover had been stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. Conclusions: It took more than 50 yr for the perennial vegetation to recover from prolonged human disturbance. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of a clear relationship between environment (e.g. precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery processes after disturbance.

  13. Kaolin-correctable prolongation of the activated partial thromboplastin time.

    PubMed

    Briselli, M F; Ellman, L

    1980-11-01

    Seven patients who had normal prothrombin times but prolonged activated partial thromboplastin times (aPTT) are described. The prolonged aPTT, obtained with micronized silica as the contact activating agent in a semi-automated optical end-point system, a nonautomated optical end-point system, and a conductivity end-point system, corrected to normal when kaolin was used as the contact activating agent. Abnormal results were also obtained with celite and ellagic acid as contact activating agents. The activities of various clotting factors were within normal limits in all cases where they were assayed. The thromboplastin dilution test was uniformly negative, and mixtures of one patient's plasma with that of another patient failed to correct the abnormal aPTT. No patients had a personal or family history of bleeding, and all underwent surgery without bleeding difficulties. This pattern of a prolonged aPTT that corrects to normal when kaolin is used as the contact activator appears to represent a previously unrecognized laboratory phenomenon.

  14. Prolonged Prevention of Retinal Degeneration with Retinylamine Loaded Nanoparticles

    PubMed Central

    Puntel, Anthony; Maeda, Akiko; Golczak, Marcin; Gao, Song-Qi; Yu, Guanping; Palczewski, Krzysztof; Lu, Zheng-Rong

    2015-01-01

    Retinal degeneration impairs the vision of millions in all age groups worldwide. Increasing evidence suggests that the etiology of many retinal degenerative diseases is associated with impairment in biochemical reactions involved in the visual cycle, a metabolic pathway responsible for regeneration of the visual chromophore (11-cis-retinal). Inefficient clearance of toxic retinoid metabolites, especially all-trans-retinal, is considered responsible for photoreceptor cytotoxicity. Primary amines, including retinylamine, are effective in lowing the concentration of all-trans-retinal within the retina and thus prevent retina degeneration in mouse models of human retinopathies. Here we achieved prolonged prevention of retinal degeneration by controlled delivery of retinylamine to the eye from polylactic acid nanoparticles in Abca4−/−Rdh8−/− (DKO) mice, an animal model of Stargardt disease/age-related macular degeneration. Subcutaneous administration of the nanoparticles containing retinylamine provided a constant supply of the drug to the eye for about a week and resulted in effective prolonged prevention of light-induced retinal degeneration in DKO mice. Retinylamine nanoparticles hold promise for prolonged prophylactic treatment of human retinal degenerative diseases, including Stargardt disease and age-related macular degeneration. PMID:25617130

  15. Resveratrol Improves Survival and Prolongs Life Following Hemorrhagic Shock

    PubMed Central

    Ayub, Ahmar; Poulose, Ninu; Raju, Raghavan

    2015-01-01

    Resveratrol has been shown to potentiate mitochondrial function and extend longevity; however, there is no evidence to support whether resveratrol can improve survival or prolong life following hemorrhagic shock. We sought to determine whether (a) resveratrol can improve survival following hemorrhage and resuscitation and (b) prolong life in the absence of resuscitation. Using a hemorrhagic injury (HI) model in the rat, we describe for the first time that the naturally occurring small molecule, resveratrol, may be an effective adjunct to resuscitation fluid. In a series of three sets of experiments we show that resveratrol administration during resuscitation improves survival following HI (p < 0.05), resveratrol and its synthetic mimic SRT1720 can significantly prolong life in the absence of resuscitation fluid (<30 min versus up to 4 h; p < 0.05), and resveratrol as well as SRT1720 restores left ventricular function following HI. We also found significant changes in the expression level of mitochondria-related transcription factors Ppar-α and Tfam, as well as Pgc-1α in the left ventricular tissues of rats subjected to HI and treated with resveratrol. The results indicate that resveratrol is a strong candidate adjunct to resuscitation following severe hemorrhage. PMID:25879628

  16. Prolonged weaning: from the intensive care unit to home.

    PubMed

    Navalesi, P; Frigerio, P; Patzlaff, A; Häußermann, S; Henseke, P; Kubitschek, M

    2014-01-01

    Weaning is the process of withdrawing mechanical ventilation which starts with the first spontaneous breathing trial (SBT). Based on the degree of difficulty and duration, weaning is classified as simple, difficult and prolonged. Prolonged weaning, which includes patients who fail 3 SBTs or are still on mechanical ventilation 7 days after the first SBT, affects a relatively small fraction of mechanically ventilated ICU patients but these, however, requires disproportionate resources. There are several potential causes which can lead to prolonged weaning. It is nonetheless important to understand the problem from the point of view of each individual patient in order to adopt appropriate treatment and define precise prognosis. An otherwise stable patient who remains on mechanical ventilation will be considered for transfer to a specialized weaning unit (SWU). Though there is not a precise definition, SWU can be considered as highly specialized and protected environments for patients requiring mechanical ventilation despite resolution of the acute disorder. Proper staffing, well defined short-term and long-term goals, attention to psychological and social problems represent key determinants of SWU success. Some patients cannot be weaned, either partly or entirely, and may require long-term home mechanical ventilation. In these cases the logistics relating to caregivers and the equipment must be carefully considered and addressed.

  17. Designing carbohydrate nanoparticles for prolonged efficacy of antimicrobial peptide.

    PubMed

    Bi, Lin; Yang, Lei; Narsimhan, Ganesan; Bhunia, Arun K; Yao, Yuan

    2011-03-10

    In this work, carbohydrate nanoparticles were created to prolong the efficacy of antimicrobial peptide against pathogens. Nisin and Listeria monocytogenes were used as the peptide and pathogen models, respectively, and phytoglycogen (PG)-based nanoparticles were developed as carriers of nisin. PG from su1 mutant maize was subjected to β-amylolysis as well as subsequent succinate or octenyl succinate substitutions. The goal was to minimize the loss of peptide during storage and meanwhile realize an effective release in the presence of bacteria. The capabilities of PG derivatives as carriers of nisin were evaluated using centrifugal ultrafiltration, zeta-potential, and the initial availability of nisin against L. monocytogenes. All methods indicated that nisin loading was favored by a high degree of substitution (DS), presence of hydrophobic octenyl moiety, and β-amylolysis of PG nanoparticles. To evaluate the prolonged nisin efficacy, preparations containing nisin and PG derivatives were loaded into a BHI-agar deep-well model (mimicking nisin depletion at the nutrient-containing surface). The residual inhibitory activities of preparations against L. monocytogenes were monitored during 21 days of storage at 4 °C. The results showed that all PG derivatives led to the prolonged retention of nisin activity and the longest retention was associated with high DS, β-amylolysis, and octenyl succinate. Evidently, both electrostatic and hydrophobic interactions are the driving forces of nisin adsorption, and the glucan structure at the nanoparticle surface also affects nisin loading and retention during storage.

  18. Characterization of new stable ghrelin analogs with prolonged orexigenic potency.

    PubMed

    Maletínská, Lenka; Pýchová, Miroslava; Holubová, Martina; Blechová, Miroslava; Demianová, Zuzana; Elbert, Tomáš; Železná, Blanka

    2012-03-01

    Ghrelin, the only known peripherally produced and centrally acting peptide that stimulates food intake, is synthesized primarily in the stomach and acts through the growth hormone secretagogue receptor (GHS-R1a). In addition to its orexigenic effect, ghrelin stimulates the release of growth hormone (GH). In this study, we investigated the biological properties of full-length and shortened ghrelin analogs in which octanoylated Ser(3) is replaced with an octanoic acid moiety coupled to diaminopropionic acid (Dpr). Ghrelin analogs stabilized with Dpr(N-octanoyl) in position 3 and noncoded amino acids in position 1 (sarcosine) and/or position 4 (naphthylalanine or cyclohexylalanine) were found to possess affinities similar to those of ghrelin for cell membranes with transfected GHS-R1a. In vivo, the prolonged orexigenic effects of analogs containing Dpr(N-octanoyl)(3) compared with that of ghrelin in adult mice and a similar impact on GH secretion in young mice were found. Full-length [Dpr(N-octanoyl)(3)]ghrelin and its analogs with a noncoded amino acid in position 1 and/or 4 showed significantly prolonged stability in blood plasma compared with that of ghrelin. Ghrelin analogs with a prolonged orexigenic effect are potential treatments for GH deficiency or cachexia that accompanies chronic diseases. Desoctanoylated ghrelin analogs and N-terminal penta- and octapeptides of ghrelin did not show any biological activity.

  19. Is re-feeding efficiency compromised by prolonged starvation during aestivation in the green striped burrowing frog, Cyclorana alboguttata?

    PubMed

    Cramp, Rebecca L; Franklin, Craig E

    2003-12-01

    We examined several morphological parameters of the gastrointestinal tract, digesta passage rates, and nutrient assimilation efficiencies of Green-striped Burrowing frogs (Cyclorana alboguttata) following prolonged fasting during three months of aestivation and compared these with frogs that had been continuously fed. Whole animal digesta passage rates were significantly reduced following three months aestivation as a result of a decreased digesta evacuation rate from the stomach. Furthermore, food was selectively retained in the small intestine for an increased time following three months of aestivation. Overall digestibility of food and nitrogen, carbon, and energy extraction efficiencies were not significantly different from control values following three months of aestivation. These findings suggest that C. alboguttata employs reduced digesta passage rates so as to maximize nutrient assimilation efficiency following prolonged food deprivation during aestivation.

  20. Effects of prolonged patellar tendon vibration on force steadiness in quadriceps femoris during force-matching task.

    PubMed

    Saito, Akira; Ando, Ryosuke; Akima, Hiroshi

    2016-01-01

    The quadriceps femoris (QF) muscle group plays an essential role in human movement, such as standing, walking and running. The ability to maintain a steady force during physical activity of the human lower limb is important for mobility, postural control and balance. Although prolonged mechanical vibration of the muscle-tendon unit can moderate the efficacy of synaptic input from Ia afferent onto the α-motor neuron pathway, the effect of prolonged tendon vibration on fluctuations of knee extensor force has received little attention. The purpose of the present study was to examine the effects of prolonged patellar tendon vibration on the force steadiness of the QF muscle. Nine healthy men performed a submaximal force-matching task involving isometric knee extension before and after patellar tendon vibration or quiet seated rest (n = 7, control condition) for 30 min. The target force was 2.5, 10 and 30 % of maximal voluntary contraction (MVC). Surface electromyography (EMG) of the four QF synergists was recorded and normalized to EMG amplitude during the MVC. The knee extension force and the EMG amplitude of vastus medialis during the MVC were significantly reduced after the vibration, but did not significantly decrease in the control condition. Fluctuations of force and normalized EMG of individual QF muscles at each submaximal force level did not significantly change after the vibration. We conclude that prolonged patellar tendon vibration does not influence the force steadiness of the QF muscle during an isometric force-matching task.

  1. Microencapsulation of aspartame by double emulsion followed by complex coacervation to provide protection and prolong sweetness.

    PubMed

    Rocha-Selmi, Glaucia A; Bozza, Fernanda T; Thomazini, Marcelo; Bolini, Helena M A; Fávaro-Trindade, Carmen S

    2013-08-15

    The objective of this work was to microencapsulate aspartame by double emulsion followed by complex coacervation, aiming to protect it and control its release. Six treatments were prepared using sunflower oil to prepare the primary emulsion and gelatin and gum Arabic as the wall materials. The microcapsules were evaluated structurally with respect to their sorption isotherms and release into water (36°C and 80°C). The microcapsules were multinucleated, not very water-soluble or hygroscopic and showed reduced rates of equilibrium moisture content and release at both temperatures. FTIR confirmed complexation between the wall materials and the intact nature of aspartame. The results indicated it was possible to encapsulate aspartame with the techniques employed and that these protected the sweetener even at 80°C. The reduced solubility and low release rates indicated the enormous potential of the vehicle developed in controlling the release of the aspartame into the food, thus prolonging its sweetness.

  2. Glut4 is upregulated despite decreased insulin signaling during prolonged fasting in northern elephant seal pups.

    PubMed

    Viscarra, Jose A; Vázquez-Medina, José Pablo; Crocker, Daniel E; Ortiz, Rudy M

    2011-01-01

    Postprandial cellular glucose uptake is dependent on an insulin-signaling cascade in muscle and adipose tissue, resulting in the translocation of the insulin-dependent glucose transporter 4 (Glut4) into the plasma membrane. Additionally, extended food deprivation is characterized by suppressed insulin signaling and decreased Glut4 expression. Northern elephant seals are adapted to prolonged fasts characterized by high levels of plasma glucose. To address the hypothesis that the fasting-induced decrease in insulin is associated with reduced insulin signaling in prolonged fasted seals, we compared the adipose protein levels of the cellular insulin-signaling pathway, Glut4 and plasma glucose, insulin, cortisol, and adiponectin concentrations between Early (n = 9; 2-3 wks postweaning) and Late (n = 8; 6-8 wks postweaning) fasted seals. Plasma adiponectin (230 ± 13 vs. 177 ± 11 ng/ml), insulin (2.7 ± 0.4 vs. 1.0 ± 0.1 μU/ml), and glucose (9.8 ± 0.5 vs. 8.0 ± 0.3 mM) decreased, while cortisol (124 ± 6 vs. 257 ± 30 nM) doubled with fasting. Glut4 increased (31%) with fasting despite the significant decreases in the cellular content of phosphatidylinositol 3-kinase as well as phosphorylated insulin receptor, insulin receptor substrate-1, and Akt2. Increased Glut4 may have contributed to the decrease in plasma glucose, but the decrease in insulin and insulin signaling suggests that Glut4 is not insulin-dependent in adipose tissue during prolonged fasting in elephant seals. The reduction of plasma glucose independent of insulin may make these animals an ideal model for the study of insulin resistance.

  3. Prolonged treatment with glucocorticoid dexamethasone suppresses melatonin production by the chick pineal gland and retina.

    PubMed

    Zawilska, Jolanta B; Sadowska, Magdalena

    2002-01-01

    The chick pineal gland and retina synthesize melatonin in a circadian rhythm with high levels during the night. The rhythmic changes in the hormone production result predominantly from the fluctuation in the activity of serotonin N-acetyltransferase (AA-NAT), a penultimate and key regulatory enzyme in melatonin biosynthesis. The aim of this study was to analyze the effects of an acute and prolonged in vivo treatment with a glucocorticoid dexamethasone (4 mg/kg, ip) on the nocturnal increase in AA-NAT activity in chick pineal gland and retina. In acute experiments, dexamethasone (single dose)-injected chicks were killed after 2 h, while in prolonged experiments the glucocorticoid was given once daily for 7 days and the animals were killed 26-32 h after the last injection. Acute administration of dexamethasone did not affect AA-NAT activity in the chick pineal gland and retina. In the pineal glands and retinas of chicks that were treated with dexamethasone for one week and then killed at the end of the light phase of the 12:12 h light-dark cycle, AA-NAT activity was significantly higher than the enzyme activity found in tissues isolated from the vehicle-treated (control) animals. In addition to that, the nocturnal increase in pineal and, to a lower extent, retinal AA-NAT activity was significantly lower in dexamethasone-treated birds when compared with the respective control groups. It is suggested that prolonged treatment of animals with dexamethasone reduces the amplitude of the rhythmic melatonin production, a phenomenon which may affect chronobiological processes being under control of this hormone.

  4. Injectable microparticle-gel system for prolonged and localized lidocaine release. I. In vitro characterization.

    PubMed

    Chen, Pen-Chung; Park, Yoon Jeong; Chang, Li-Chien; Kohane, Daniel S; Bartlett, Robert H; Langer, Robert; Yang, Victor C

    2004-09-01

    Current treatment protocol for postoperative pain is to infuse anesthetic solution around nerves or into the epidural space. This clinical practice is beset by the short duration of the anesthetic effect unless the infusion is continuous. Continuous infusion, however, requires hospitalization of the patients, thereby increasing medical costs. In addition, it also causes systemic accumulation of the drug. We reported herein a novel treatment for the postoperative pain by applying to the surgical site a biodegradable microsphere-gel system for prolonged and localized release of encapsulated anesthetic drugs. This lidocaine-containing biodegradable poly(D,L-lactic acid) (PLA) microsphere system, although being established previously by other investigators, was hindered by a burst release and a followed rapid release of the drug within several hours in vitro. In this article, we demonstrated that by a step-by-step modification of the formulation, prolonged release of lidocaine, up to several days in vitro, could be achieved. Differential scanning calorimetry revealed a lower glass transition temperature for these lidocaine-loaded microspheres comparing to that of lidocaine-free microspheres. This decreased Tg explained for the tendency of the lidocaine-loaded microspheres to physically fuse at higher temperatures. In vitro studies showed that microspheres, when loaded with 35% lidocaine, yielded a threefold increase in the degradation rate. The molecular weight of PLA of the drug-loaded microspheres was reduced by 50% within a period of 1 month. Based on the results (of prolonged lidocaine release and rapid PLA microsphere degradation), this lidocaine-loaded PLA microsphere system could offer a simple solution to the treatment of postoperative pain.

  5. Neurosteroid prolongs GABAA channel deactivation by altering kinetics of desensitized states.

    PubMed

    Zhu, W J; Vicini, S

    1997-06-01

    Fast applications of GABA (1 mM) to nucleated and outside-out patches excised from granule neurons in cerebellar slices from developing rats evoked currents with a double exponential time course reminiscent of that of IPSCs. A neurosteroid 3alpha, 21dihydroxy-5alpha-pregnan-20-one (THDOC) remarkably increased the slow deactivation time constant and slowed down recovery from desensitization, as estimated by paired-pulse GABA applications. THDOC also reduced the amplitude of GABA currents, whereas it failed to affect the fast deactivation component and its relative contribution to peak amplitude. The effects of THDOC on slow deactivation were greater in rats younger than postnatal day 13 (P13) as compared with rats at P30-P35. THDOC failed to alter deactivation of short responses induced by a less-potent agonist taurine at saturating doses. These responses had deactivation kinetics described by a fast single exponential decay, little desensitization, and quick recovery. However, THDOC slowed deactivation if taurine responses were long enough to allow consistent desensitization, suggesting that desensitized states are required for the neurosteroid to modulate GABA responses. In outside-out patches, just as desensitized states prolonged GABA responses by producing reopening of channels activated by brief GABA pulses, THDOC increased the channel open probability by further increasing the number of late channel openings, resulting in a prolongation of the slow deactivation. Our data suggest that neurosteroid potentiates the inhibitory postsynaptic transmission via the prolongation of the slow deactivation and that the alteration of kinetics of entry and exit from desensitized states underlies the allosteric modification of GABAA receptors by neurosteroids.

  6. Survival time of cardiac allografts prolonged by isogeneic BMT in mice.

    PubMed

    Chen, Z; Jiang, H; Chen, R; Feng, S; Jin, J; Bi, Y; Yang, H; Chen, J

    2012-08-01

    To find an approach to prolong the survival time of cardiac allografts in a BALB/c-to-C57/BL6 heterotopic heart transplant model and to try to figure out related chemokines and cytokines, isogeneic and allogeneic BM cells were obtained from pregnant C57/BL6 (♀C57/BL6 × ♂BALB/c) and regular BALB/c mice and injected to the half lethally irradiated C57/BL6 mice 1 day before heart transplantation. Recipients were treated with CsA or phosphate-buffered saline for 7 days. Isogeneic BMT (iBMT) from pregnant C57/BL6 mice was observed to significantly prolong the survival of BALB/c allografts and reduce the lymphocyte infiltration. Allogeneic BMT (aBMT) and iBMT both exhibited signicantly less T-cell proliferation reactivity and the similar degree of chimerism. There was no significant difference in these groups of IFN-γ and IL-4 production. The level of chemokine MIG (CXCL9) dramatically decreased in aBMT and iBMT groups compared with the control group. But there were no significant differences between aBMT and iBMT group. IL-17 and RORγ(t) (receptor-related orphan receptor) production were downregulated in iBMT recipients. These results indicate that iBMT can prolong the survival of cardiac allografts. IL-17 production downregulated in iBMT recipients. This means that iBMT may have important therapeutic implications.

  7. LONG-TERM BEHAVIORAL EFFECTS IN A RAT MODEL OF PROLONGED POSTNATAL MORPHINE EXPOSURE

    PubMed Central

    Craig, Michael M.; Bajic, Dusica

    2015-01-01

    Prolonged morphine treatment in neonatal pediatric populations is associated with a high incidence of opioid tolerance and dependence. Despite the clinical relevance of this problem, our knowledge of the long-term consequences is sparse. The main objective of this study was to investigate whether prolonged morphine administration in a neonatal rat is associated with long-term behavioral changes in adulthood. Newborn animals received either morphine (10mg/kg) or equal volume of saline subcutaneously twice daily for the first 2 weeks of life. Morphine treated animals underwent 10 days of morphine weaning to reduce the potential for observable physical signs of withdrawal. Animals were subjected to non-stressful testing (locomotor activity recording and a Novel-Object Recognition test) at a young age (PD27-31) or later in adulthood (PD55-56), as well as stressful testing (calibrated forceps test, Hot Plate test, and Forced Swim test) only in adulthood. Analysis revealed that prolonged neonatal morphine exposure resulted in decreased thermal, but not mechanical threshold. Importantly, no differences were found for total locomotor activity (proxy of drug reward/reinforcement behavior), individual Forced Swim test behaviors (proxy of affective processing), or Novel-Object Recognition test. Performance on the Novel-Object Recognition test was compromised in the morphine treated group at the young age, however the effect disappeared in adulthood. These novel results provide insight into the long-term consequences of opioid treatment during an early developmental period and suggest long-term neuroplastic differences in sensory processing related to thermal stimuli. PMID:26214209

  8. Depressive Disorders during Weaning from Prolonged Mechanical Ventilation

    PubMed Central

    Jubran, Amal; Lawm, Gerald; Kelly, Joanne; Duffner, Lisa A.; Gungor, Gokay; Collins, Eileen G.; Lanuza, Dorothy M.; Hoffman, Leslie A.; Tobin, Martin J.

    2010-01-01

    Purpose Patients who require mechanical ventilation are at risk of emotional stress because of total dependence on a machine for breathing. The stress may negatively impact ventilator weaning and survival. The purpose of this study was to determine whether depressive disorders in patients being weaned from prolonged mechanical ventilation are linked to weaning failure and decreased survival. Methods A prospective study of 478 consecutive patients transferred to a long-term acute care hospital for weaning from prolonged ventilation was undertaken. A clinical psychologist conducted a psychiatric interview to assess for the presence of depressive disorders. Results Of the 478 patients, 142 had persistent coma or delirium and were unable to be evaluated for depressive disorders. Of the remaining 336 patients, 142 (42%) were diagnosed with depressive disorders. In multivariate analysis, co-morbidity score (odds ratio [OR], 1.23, p=0.007), functional dependence before the acute illness (OR, 1.70, p=0.03), and history of psychiatric disorders (OR, 3.04, p=0.0001) were independent predictors of depressive disorders. The rate of weaning failure was higher in patients with depressive disorders than in those without such disorders (61% versus 33%, p=0.0001), as was mortality (24% versus 10%, p=0.0008). The presence of depressive disorders was independently associated with mortality (OR, 4.3; p=0.0002); age (OR, 1.06; p=0.001) and co-morbidity score (OR, 1.24; p=0.02) also predicted mortality. Conclusion Depressive disorders were diagnosed in 42% of patients who are being weaned from prolonged ventilation. Patients with depressive disorders were more likely to experience weaning failure and death. PMID:20232042

  9. Neural compensation within the human triceps surae during prolonged walking.

    PubMed

    Cronin, Neil J; Peltonen, Jussi; Sinkjaer, Thomas; Avela, Janne

    2011-02-01

    During human walking, muscle activation strategies are approximately constant across consecutive steps over a short time, but it is unknown whether they are maintained over a longer duration. Prolonged walking may increase tendinous tissue (TT) compliance, which can influence neural activation, but the neural responses of individual muscles have not been investigated. This study investigated the hypothesis that muscle activity is up- or down-regulated in individual triceps surae muscles during prolonged walking. Thirteen healthy subjects walked on a treadmill for 60 min at 4.5 km/h, while triceps surae muscle activity, maximal muscle compound action potentials, and kinematics were recorded every 5 min, and fascicle lengths were estimated at the beginning and end of the protocol using ultrasound. After 1 h of walking, soleus activity increased by 9.3 ± 0.2% (P < 0.05) and medial gastrocnemius activity decreased by 9.3 ± 0.3% (P < 0.01). Gastrocnemius fascicle length at ground contact shortened by 4.45 ± 0.99% (P < 0.001), whereas soleus fascicle length was unchanged (P = 0.988). Throughout the stance phase, medial gastrocnemius fascicle lengthening decreased by 44 ± 13% (P < 0.001), whereas soleus fascicle lengthening amplitude was unchanged (P = 0.650). The data suggest that a compensatory neural strategy exists between triceps surae muscles and that changes in muscle activation are generally mirrored by changes in muscle fascicle length. These findings also support the notion of muscle-specific changes in TT compliance after prolonged walking and highlight the ability of the CNS to maintain relatively constant movement patterns in spite of neuromechanical changes in individual muscles.

  10. Adaptive prolonged postreproductive life span in killer whales.

    PubMed

    Foster, Emma A; Franks, Daniel W; Mazzi, Sonia; Darden, Safi K; Balcomb, Ken C; Ford, John K B; Croft, Darren P

    2012-09-14

    Prolonged life after reproduction is difficult to explain evolutionarily unless it arises as a physiological side effect of increased longevity or it benefits related individuals (i.e., increases inclusive fitness). There is little evidence that postreproductive life spans are adaptive in nonhuman animals. By using multigenerational records for two killer whale (Orcinus orca) populations in which females can live for decades after their final parturition, we show that postreproductive mothers increase the survival of offspring, particularly their older male offspring. This finding may explain why female killer whales have evolved the longest postreproductive life span of all nonhuman animals.

  11. Prolonged ictal monoparesis with parietal Periodic Lateralised Epileptiform Discharges (PLEDs).

    PubMed

    Murahara, Takashi; Kinoshita, Masako; Usami, Kiyohide; Matsui, Masashi; Yamashita, Kouhei; Takahashi, Ryosuke; Ikeda, Akio

    2013-06-01

    We report a patient with prolonged monoparesis and parietal periodic lateralised epileptiform discharges (PLEDs). The patient was a 73-year-old man with chronic myelomonocytic leukaemia who developed persisting monoparesis of the right arm, sensory aphasia, and finger agnosia, initially associated with focal clonic seizures. These neurological deficits remained for seven days without subsequent focal clonic seizures. The EEG showed left-sided PLEDs, maximal in the left occipito-parietal area. Ten days later, following phenytoin treatment, these symptoms suddenly improved and parietal PLEDs disappeared. Sustained PLEDs in the left parietal region may have been causally associated with ictal paresis in this patient.

  12. How long would SDH/SONET be prolonged?

    NASA Astrophysics Data System (ADS)

    Tao, Zhiyong; Mao, Qian

    2004-04-01

    As we all know, the increasing speed of data traffic is exceeding gradually from voice in today"s communication network. The main reason is the explosive of Internet. The controversy with IP over ATM/SDH/Optical becomes hotter and hotter, Many people in the telecommunication field are doubt: HOW LONG WOULD SDH/SONET BE PROLONGED? WHAT KIND OF SDH EQUIPMENTS COULD BE USED IN THE NETWORK? With the analysis from several aspects: services in the network, new development with SDH technology, market in transport equipment, This paper is considered that the SDH with some new features would be predominant transport technology in the recent years.

  13. Hemiplegic Migraine Presenting with Prolonged Somnolence: A Case Report

    PubMed Central

    Saleh, Christian; Pierquin, Geneviève; Beyenburg, Stefan

    2016-01-01

    Hemiplegic migraine is a rare and complex disease, characterized by migraine with a reversible motor aura. Hemiplegic migraine can be easily misdiagnosed at its first presentation with an atypical severe form of migraine, a stroke, multiple sclerosis, metabolic disorders, conversion disorder or an epilepsy. We present the case of a young 24-year-old male patient, who since the age of 4 years had been having multiple episodes of migraine associated with hemiparesis, paraesthesia, prolonged somnolence, aphasia and confusion. We review the literature and discuss important diagnostic findings in hemiplegic migraine to help establishing a prompt diagnosis. PMID:27790126

  14. Extracorporeal Free Flap Perfusion in Case of Prolonged Ischemia Time.

    PubMed

    Taeger, C D; Präbst, K; Beier, J P; Meyer, A; Horch, R E

    2016-04-01

    In free flap surgery, a clinically established concept still has to be found for the reduction of ischemia-related cell damage in the case of prolonged ischemia. Although promising results using extracorporeal free flap perfusion in the laboratory have been published in the past, until now this concept has not yet paved its way into clinical routine. This might be due to the complexity of perfusion systems and a lack of standardized tools. Here, we want to present the results of the first extracorporeal free flap perfusion in a clinical setting using a simple approach without the application of a complex perfusion machinery.

  15. The differential effects of prolonged exercise upon executive function and cerebral oxygenation.

    PubMed

    Tempest, Gavin D; Davranche, Karen; Brisswalter, Jeanick; Perrey, Stephane; Radel, Rémi

    2017-04-01

    The acute-exercise effects upon cognitive functions are varied and dependent upon exercise duration and intensity, and the type of cognitive tasks assessed. The hypofrontality hypothesis assumes that prolonged exercise, at physiologically challenging intensities, is detrimental to executive functions due to cerebral perturbations (indicated by reduced prefrontal activity). The present study aimed to test this hypothesis by measuring oxygenation in prefrontal and motor regions using near-infrared spectroscopy during two executive tasks (flanker task and 2-back task) performed while cycling for 60min at a very low intensity and an intensity above the ventilatory threshold. Findings revealed that, compared to very low intensity, physiologically challenging exercise (i) shortened reaction time in the flanker task, (ii) impaired performance in the 2-back task, and (iii) initially increased oxygenation in prefrontal, but not motor regions, which then became stable in both regions over time. Therefore, during prolonged exercise, not only is the intensity of exercise assessed important, but also the nature of the cognitive processes involved in the task. In contrast to the hypofrontality hypothesis, no inverse pattern of oxygenation between prefrontal and motor regions was observed, and prefrontal oxygenation was maintained over time. The present results go against the hypofrontality hypothesis.

  16. A Prolonged NO-Dependent, Opioid-Mediated Antinociceptive Effect of Hyperbaric Oxygen in Mice

    PubMed Central

    Zelinski, Lisa M.; Ohgami, Yusuke; Chung, Eunhee; Shirachi, Donald Y.; Quock, Raymond M.

    2009-01-01

    Hyperbaric oxygen (HBO2) therapy is reported to cause pain relief in several conditions of chronic pain. A single 60-min session of HBO2 treatment produced a prolonged antinociceptive effect in mice that persisted for 90 min after cessation of treatment. The HBO2-induced antinociception was significantly attenuated by pretreatment prior to HBO2 exposure with the opioid antagonist naltrexone, the non-specific nitric oxide synthase (NOS)-inhibitor NG-nitro-L-arginine methyl ester (L-NAME) and the selective neuronal NOS-inhibitor S-methyl-L-thiocitrulline (SMTC) but not the selective endothelial NOS-inhibitor N5-(1-iminoethyl)-L-ornithine (L-NIO). The antinociception was also significantly reduced by central pretreatment with a rabbit antiserum against dynorphin1-13 but not by rabbit antisera against either β-endorphin or methionine-enkephalin. The prolonged antinociceptive effect at 90 min after HBO2-induced treatment was also significantly attenuated by naltrexone but not L-NAME administered 60 min following HBO2 treatment but prior to nociceptive testing. These findings indicate that the antinociception that persists for 90 min after HBO2 exposure is mediated by nitric oxide (NO) and opioid mechanisms but that the NO involvement is critical during the HBO2 treatment and not at the time of nociceptive testing. These results are consistent with the concept that HBO2 may induce an NO-dependent release of opioid peptide to cause a long-acting antinociceptive effect. PMID:18976963

  17. Prolonged acid rain facilitates soil organic carbon accumulation in a mature forest in Southern China.

    PubMed

    Wu, Jianping; Liang, Guohua; Hui, Dafeng; Deng, Qi; Xiong, Xin; Qiu, Qingyan; Liu, Juxiu; Chu, Guowei; Zhou, Guoyi; Zhang, Deqiang

    2016-02-15

    With the continuing increase in anthropogenic activities, acid rain remains a serious environmental threat, especially in the fast developing areas such as southern China. To detect how prolonged deposition of acid rain would influence soil organic carbon accumulation in mature subtropical forests, we conducted a field experiment with simulated acid rain (SAR) treatments in a monsoon evergreen broadleaf forest at Dinghushan National Nature Reserve in southern China. Four levels of SAR treatments were set by irrigating plants with water of different pH values: CK (the control, local lake water, pH ≈ 4.5), T1 (water pH=4.0), T2 (water pH=3.5), and T3 (water pH=3.0). Results showed reduced pH measurements in the topsoil exposed to simulated acid rains due to soil acidification. Soil respiration, soil microbial biomass and litter decomposition rates were significantly decreased by the SAR treatments. As a result, T3 treatment significantly increased the total organic carbon by 24.5% in the topsoil compared to the control. Furthermore, surface soil became more stable as more recalcitrant organic matter was generated under the SAR treatments. Our results suggest that prolonged acid rain exposure may have the potential to facilitate soil organic carbon accumulation in the subtropical forest in southern China.

  18. Prolonged clot lysis time increases the risk of a first but not recurrent venous thrombosis.

    PubMed

    Karasu, Alev; Baglin, Trevor P; Luddington, Roger; Baglin, Caroline A; van Hylckama Vlieg, Astrid

    2016-03-01

    The role of the fibrinolytic system in the development of venous thrombosis (VT) is unclear. We studied the risk of first and recurrent VT associated with reduced fibrinolysis, as measured by clot lysis time (CLT). We also studied the relationship between CLT and thrombin generation to determine if any relationship between CLT and VT was affected by thrombin generation. Analyses were performed in the Thrombophilia Hypercoagulability Environmental risk for Venous Thromboembolism Study, a two-centre population-based case-control study, including 579 patients and 338 controls, with patients followed from the event to determine incidence of recurrent VT. Hypofibrinolysis was associated with a 1·8-fold increased risk of a first VT [95% confidence interval (CI) 1·2-2·7]. Adjustment for sex, age, study location and Endogenous Thrombin Potential (ETP) did not change the result. The risk of VT was 2·9-fold increased when the 90th percentiles of prolonged CLT and high ETP were combined, with the highest risk for unprovoked first events (Odds Ratio = 4·2, 95% CI 1·3-13·5). In the follow-up study the Hazard Ratio for a recurrent VT associated with hypofibrinolysis was 1·5 (95% CI 0·9-2·6). A weak dose response effect was observed in relation to prolongation of CLT and recurrent VT. Although hypofibrinolysis constitutes a risk factor for a first VT, an association with recurrence is, at best, weak.

  19. Space physiology VI: exercise, artificial gravity, and countermeasure development for prolonged space flight.

    PubMed

    Hargens, Alan R; Bhattacharya, Roshmi; Schneider, Suzanne M

    2013-09-01

    When applied individually, exercise countermeasures employed to date do not fully protect the cardiovascular and musculoskeletal systems during prolonged spaceflight. Recent ground-based research suggests that it is necessary to perform exercise countermeasures within some form of artificial gravity to prevent microgravity deconditioning. In this regard, it is important to provide normal foot-ward loading and intravascular hydrostatic-pressure gradients to maintain musculoskeletal and cardiovascular function. Aerobic exercise within a centrifuge restores cardiovascular function, while aerobic exercise within lower body negative pressure restores cardiovascular function and helps protect the musculoskeletal system. Resistive exercise with vibration stimulation may increase the effectiveness of resistive exercise by preserving muscle function, allowing lower intensity exercises, and possibly reducing risk of loss of vision during prolonged spaceflight. Inexpensive methods to induce artificial gravity alone (to counteract head-ward fluid shifts) and exercise during artificial gravity (for example, by short-arm centrifuge or exercise within lower body negative pressure) should be developed further and evaluated as multi-system countermeasures.

  20. Neoteny, Prolongation of Youth: From Naked Mole Rats to "Naked Apes" (Humans).

    PubMed

    Skulachev, Vladimir P; Holtze, Susanne; Vyssokikh, Mikhail Y; Bakeeva, Lora E; Skulachev, Maxim V; Markov, Alexander V; Hildebrandt, Thomas B; Sadovnichii, Viktor A

    2017-04-01

    It has been suggested that highly social mammals, such as naked mole rats and humans, are long-lived due to neoteny (the prolongation of youth). In both species, aging cannot operate as a mechanism facilitating natural selection because the pressure of this selection is strongly reduced due to 1) a specific social structure where only the "queen" and her "husband(s)" are involved in reproduction (naked mole rats) or 2) substituting fast technological progress for slow biological evolution (humans). Lists of numerous traits of youth that do not disappear with age in naked mole rats and humans are presented and discussed. A high resistance of naked mole rats to cancer, diabetes, cardiovascular and brain diseases, and many infections explains why their mortality rate is very low and almost age-independent and why their lifespan is more than 30 years, versus 3 years in mice. In young humans, curves of mortality versus age start at extremely low values. However, in the elderly, human mortality strongly increases. High mortality rates in other primates are observed at much younger ages than in humans. The inhibition of the aging process in humans by specific drugs seems to be a promising approach to prolong our healthspan. This might be a way to retard aging, which is already partially accomplished via the natural physiological phenomenon neoteny.

  1. Development and Optimization of a Novel Prolonged Release Formulation to Resist Alcohol-Induced Dose Dumping.

    PubMed

    Gujjar, Chaitanya Yogananda; Rallabandi, Balaramesha Chary; Gannu, Ramesh; Deulkar, Vallabh Subashrao

    2016-04-01

    Alcohol-induced dose dumping is a serious concern for the orally administered prolonged release dosage forms. The study was designed to optimize the independent variables, propylene glycol alginate (PGA), Eudragit RS PO (ERS) and coating in mucoadhesive quetiapine prolonged release tablets 200 mg required for preventing the alcohol-induced dose dumping. Optimal design based on response surface methodology was employed for the optimization of the composition. The formulations are evaluated for in vitro drug release in hydrochloric acid alone and with 40% v/v ethanol. The responses, dissolution at 120 min without alcohol (R1) and dissolution at 120 min with alcohol (R2), were statistically evaluated and regression equations are generated. PGA as a hydrophilic polymeric matrix was dumping the dose when dissolutions are carried in 0.1 N hydrochloric acid containing 40% v/v ethanol. ERS addition was giving structural support to the swelling and gelling property of PGA, and thus, was reducing the PGA erosion in dissolution media containing ethanol. Among the formulations, four formulations with diverse composition were meeting the target dissolution (30-40%) in both the conditions. The statistical validity of the mathematical equations was established, and the optimum concentration of the factors was established. Validation of the study with six confirmatory runs indicated high degree of prognostic ability of response surface methodology. Further coating with ReadiLycoat was providing an additional resistance to the alcohol-induced dose dumping. Optimized compositions showed resistance to dose dumping in the presence of alcohol.

  2. Rapamycin Prolongs Cardiac Allograft Survival in a Mouse Model by Inducing Myeloid-Derived Suppressor Cells.

    PubMed

    Nakamura, T; Nakao, T; Yoshimura, N; Ashihara, E

    2015-09-01

    Mammalian target of rapamycin (mTOR) inhibitors are the main immunosuppressive drugs for organ transplant recipients. Nevertheless, the mechanisms by which mTOR inhibitors induce immunosuppression is not fully understood. Myeloid-derived suppressor cells (MDSCs) maintain host immunity; however, the relationship between mTOR inhibitors and MDSCs is unclear. Here, the results from a murine cardiac transplantation model revealed that rapamycin treatment (3 mg/kg, intraperitoneally on postoperative days 0, 2, 4, and 6) led to the recruitment of MDSCs and increased their expression of inducible nitric oxide synthase (iNOS). Immunohistochemical analysis revealed that rapamycin induced the migration of iNOS-expressing MDSCs into the subintimal space within the allograft vessels, resulting in a significant prolongation of graft survival compared with that in the untreated group (67 days vs. 7 days, respectively). These effects were counterbalanced by the administration of an anti-Gr-1, which reduced allograft survival to 21 days. Moreover, adoptive transcoronary arterial transfer of MDSCs from rapamycin-treated recipients prolonged allograft survival; this increase was reversed by the anti-Gr-1 antibody. Finally, co-administration of rapamycin and a mitogen-activated protein kinase kinase (MEK) inhibitor trametinib reversed rapamycin-mediated MDSC recruitment. Thus, the mTOR and Raf/MEK/extracellular signal regulated kinase (ERK) signaling pathways appear to play an important role in MDSC expansion.

  3. Evolution of prolonged development: a life table analysis for periodical cicadas.

    PubMed

    Karban, R

    1997-10-01

    According to conventional wisdom, natural selection should favor early reproduction. Prolonged development of 13 and 17 yr has been difficult to explain for periodical cicadas. Earlier, I hypothesized that development may be long for periodical cicadas because fecundity increases as a function of longer development with little increased risk of mortality. In this article, I tested whether the fecundity was greater for 17-yr cicadas than for 13-yr cicadas and estimated the shape of the survivorship curve. A cohort of 17-yr cicadas was followed from 1979 through 1996. Most mortality occurred during the first 2 yr; thereafter mortality was uncommon. Across 17 yr, adult densities increased at five out of seven sites, and in no case did the change exceed three times. Seventeen-year adults had heavier ovaries than did 13-yr adults; this effect was greater for Magicicada cassini (1.80 times) than for Magicicada decim (1.16 times). For M. cassini, the extra fecundity associated with 17-yr development swamped the potential advantages of more frequent reproduction of 13-yr forms under most conditions. For M. decim, realistically low rates of mortality roughly matched the small effect of development on fecundity. Prolonged development in periodical cicadas may be explained adequately by the demographic hypothesis, although it may also reduce predation risk to adults or result from strong selection for large body size.

  4. Plasma protein changes in horse after prolonged physical exercise: a proteomic study.

    PubMed

    Scoppetta, Fausto; Tartaglia, Micaela; Renzone, Giovanni; Avellini, Luca; Gaiti, Alberto; Scaloni, Andrea; Chiaradia, Elisabetta

    2012-07-19

    Physical exercise induces various stress responses and metabolic adaptations that have not yet been completely elucidated. Novel biomarkers are needed in sport veterinary medicine to monitor training levels and to detect subclinical conditions that can develop into exercise-related diseases. In this study, protein modifications in horse plasma induced by prolonged, aerobic physical exercise were investigated by using a proteomic approach based on 2-DE and combined mass spectrometry procedures. Thirty-eight protein spots, associated with expression products of 13 genes, showed significant quantitative changes; spots identified as membrane Cu amine oxidase, α-1 antitrypsin, α-1 antitrypsin-related protein, caeruloplasmin, α-2 macroglobulin and complement factor C4 were augmented in relative abundance after the race, while haptoglobin β chain, apolipoprotein A-I, transthyretin, retinol binding protein 4, fibrinogen γ chain, complement factor B and albumin fragments were reduced. These results indicate that prolonged physical exercise affects plasma proteins involved in pathways related to inflammation, coagulation, immune modulation, oxidant/antioxidant activity and cellular and vascular damage, with consequent effects on whole horse metabolism.

  5. Polyvinylpyrrolidone induced artefactual prolongation of activated partial thromboplastin times in intravenous drug users with renal failure.

    PubMed

    Kristoffersen, A H; Bjånes, T K; Jordal, S; Leh, S; Leh, F; Svarstad, E

    2016-05-01

    Essentials Prolonged activated partial thromboplastin times (APTT) were found in drug users with renal failure. An oral methadone solution containing polyvinylpyrrolidone (PVP) had been injected intravenously. Spiking normal plasma with increasing concentrations of PVP resulted in artifically prolonged APTT. APTT prolongation may indicate PVP deposits as underlying cause in patients with renal failure.

  6. Influence of a Prolonged Tennis Match Play on Serve Biomechanics

    PubMed Central

    Martin, Caroline; Bideau, Benoit; Delamarche, Paul; Kulpa, Richard

    2016-01-01

    The aim of this study was to quantify kinematic, kinetic and performance changes that occur in the serve throughout a prolonged tennis match play. Serves of eight male advanced tennis players were recorded with a motion capture system before, at mid-match, and after a 3-hour tennis match. Before and after each match, electromyographic data of 8 upper limb muscles obtained during isometric maximal voluntary contraction were compared to determine the presence of muscular fatigue. Vertical ground reaction forces, rating of perceived exertion, ball speed, and ball impact height were measured. Kinematic and upper limb kinetic variables were computed. The results show decrease in mean power frequency values for several upper limb muscles that is an indicator of local muscular fatigue. Decreases in serve ball speed, ball impact height, maximal angular velocities and an increase in rating of perceived exertion were also observed between the beginning and the end of the match. With fatigue, the majority of the upper limb joint kinetics decreases at the end of the match. No change in timing of maximal angular velocities was observed between the beginning and the end of the match. A prolonged tennis match play may induce fatigue in upper limb muscles, which decrease performance and cause changes in serve maximal angular velocities and joint kinetics. The consistency in timing of maximal angular velocities suggests that advanced tennis players are able to maintain the temporal pattern of their serve technique, in spite of the muscular fatigue development. PMID:27532421

  7. Caffeine ingestion, affect and perceived exertion during prolonged cycling.

    PubMed

    Backhouse, Susan H; Biddle, Stuart J H; Bishop, Nicolette C; Williams, Clyde

    2011-08-01

    Caffeine's metabolic and performance effects have been widely reported. However, caffeine's effects on affective states during prolonged exercise are unknown. Therefore, this was examined in the present study. Following an overnight fast and in a randomised, double-blind, counterbalanced design, twelve endurance trained male cyclists performed 90 min of exercise at 70% VO(₂ max) 1h after ingesting 6 mg kg⁻¹ BM of caffeine (CAF) or placebo (PLA). Dimensions of affect and perceived exertion were assessed at regular intervals. During exercise, pleasure ratings were better maintained (F(₃,₃₈)=4.99, P < 0.05) in the CAF trial compared to the PLA trial with significantly higher ratings at 15, 30 and 75 min (all P < 0.05). Perceived exertion increased (F(₃,₃₈) = 19.86, P < 0.01) throughout exercise and values, overall, were significantly lower (F(₁,₁₁) = 9.26, P < 0.05) in the CAF trial compared to the PLA trial. Perceived arousal was elevated during exercise but did not differ between trials. Overall, the results suggest that a moderate dose of CAF ingested 1h prior to exercise maintains a more positive subjective experience during prolonged cycling. This observation may partially explain caffeine's ergogenic effects.

  8. High efficiency holographic Bragg grating with optically prolonged memory

    PubMed Central

    Khoo, Iam Choon; Chen, Chun-Wei; Ho, Tsung-Jui

    2016-01-01

    In this paper, we show that photosensitive azo-dye doped Blue-phase liquid crystals (BPLC) formed by natural molecular self-assembly are capable of high diffraction efficiency holographic recording with memory that can be prolonged from few seconds to several minutes by uniform illumination with the reference beam. Operating in the Bragg regime, we have observed 50 times improvement in the grating diffraction efficiency and shorter recording time compared to previous investigations. The enabling mechanism is BPLC’s lattice distortion and index modulation caused by the action of light on the azo-dopant; upon photo-excitation, the azo-molecules undergo transformation from the oblong-shaped Trans-state to the bent-shaped Cis-state, imparting disorder and also cause the surrounding BPLC molecules to undergo coupled flow & reorientation leading to lattice distortion and index modulation. We also showed that the same mechanism at work here that facilitates lattice distortion can be used to frustrate free relaxation of the lattice distortion, thereby prolonging the lifetime of the written grating, provided the reference beam is kept on after recording. Due to the ease in BPLC fabrication and the availability of azo-dopants with photosensitivity throughout the entire visible spectrum, one can optimize the controlling material and optical parameters to obtain even better performance. PMID:27782197

  9. High efficiency holographic Bragg grating with optically prolonged memory

    NASA Astrophysics Data System (ADS)

    Khoo, Iam Choon; Chen, Chun-Wei; Ho, Tsung-Jui

    2016-10-01

    In this paper, we show that photosensitive azo-dye doped Blue-phase liquid crystals (BPLC) formed by natural molecular self-assembly are capable of high diffraction efficiency holographic recording with memory that can be prolonged from few seconds to several minutes by uniform illumination with the reference beam. Operating in the Bragg regime, we have observed 50 times improvement in the grating diffraction efficiency and shorter recording time compared to previous investigations. The enabling mechanism is BPLC’s lattice distortion and index modulation caused by the action of light on the azo-dopant; upon photo-excitation, the azo-molecules undergo transformation from the oblong-shaped Trans-state to the bent-shaped Cis-state, imparting disorder and also cause the surrounding BPLC molecules to undergo coupled flow & reorientation leading to lattice distortion and index modulation. We also showed that the same mechanism at work here that facilitates lattice distortion can be used to frustrate free relaxation of the lattice distortion, thereby prolonging the lifetime of the written grating, provided the reference beam is kept on after recording. Due to the ease in BPLC fabrication and the availability of azo-dopants with photosensitivity throughout the entire visible spectrum, one can optimize the controlling material and optical parameters to obtain even better performance.

  10. Prolonged fasting impairs neural reactivity to visual stimulation.

    PubMed

    Kohn, N; Wassenberg, A; Toygar, T; Kellermann, T; Weidenfeld, C; Berthold-Losleben, M; Chechko, N; Orfanos, S; Vocke, S; Laoutidis, Z G; Schneider, F; Karges, W; Habel, U

    2016-01-01

    Previous literature has shown that hypoglycemia influences the intensity of the BOLD signal. A similar but smaller effect may also be elicited by low normal blood glucose levels in healthy individuals. This may not only confound the BOLD signal measured in fMRI, but also more generally interact with cognitive processing, and thus indirectly influence fMRI results. Here we show in a placebo-controlled, crossover, double-blind study on 40 healthy subjects, that overnight fasting and low normal levels of glucose contrasted to an activated, elevated glucose condition have an impact on brain activation during basal visual stimulation. Additionally, functional connectivity of the visual cortex shows a strengthened association with higher-order attention-related brain areas in an elevated blood glucose condition compared to the fasting condition. In a fasting state visual brain areas show stronger coupling to the inferior temporal gyrus. Results demonstrate that prolonged overnight fasting leads to a diminished BOLD signal in higher-order occipital processing areas when compared to an elevated blood glucose condition. Additionally, functional connectivity patterns underscore the modulatory influence of fasting on visual brain networks. Patterns of brain activation and functional connectivity associated with a broad range of attentional processes are affected by maturation and aging and associated with psychiatric disease and intoxication. Thus, we conclude that prolonged fasting may decrease fMRI design sensitivity in any task involving attentional processes when fasting status or blood glucose is not controlled.

  11. Effect of Multiparity and Prolonged Lactation on Bone Mineral Density

    PubMed Central

    Natung, Tanie; Barooah, Rituparna; Ahanthem, Santa Singh

    2016-01-01

    Objectives This study was done to determine the effect of multiparity and prolonged lactation on bone mineral density (BMD). Methods This cross-sectional study included 196 perimenopausal and postmenopausal women aged 40 to 60 years old. Age, body mass index (BMI), menopausal status, duration of menopause, parity and total duration of lactation, nutritional history were recorded. Lumbar spine (LS; L2-L4) and femur neck (FN) BMD were measured using dual energy X-ray absorptiometry. Correlation of parity and lactation with BMD were investigated using multiple regression analysis. Results Parity was inversely correlated to BMD for LS (β = −0.266, P = 0.001) and FN (β = −0.380, P = 0.000). This relation remained significant even after adjusting for age, BMI and duration of menopause. Duration of lactation was inversely correlated with BMD for LS (β = −0.271, P = 0.001) but no for FN (β = −0.124, P = 0.130). Conclusions Multiparity and prolonged lactation have negative impact on BMD especially with in a socioeconomic group whose nutritional intake is borderline. Our data support that parity and duration of lactation can be associated with future osteoporosis. PMID:28119896

  12. Cyclodextrin modified PLLA parietal reinforcement implant with prolonged antibacterial activity.

    PubMed

    Vermet, G; Degoutin, S; Chai, F; Maton, M; Flores, C; Neut, C; Danjou, P E; Martel, B; Blanchemain, N

    2017-02-12

    The use of textile meshes in hernia repair is widespread in visceral surgery. Though, mesh infection is a complication that may prolong the patient recovery period and consequently presents an impact on public health economy. Such concern can be avoided thanks to a local and extended antibiotic release on the operative site. In recent developments, poly-l-lactic acid (PLLA) has been used in complement of polyethyleneterephthalate (Dacron®) (PET) or polypropylene (PP) yarns in the manufacture of semi-resorbable parietal implants. The goal of the present study consisted in assigning drug reservoir properties and prolonged antibacterial effect to a 100% PLLA knit through its functionalization with a cyclodextrin polymer (polyCD) and activation with ciprofloxacin. The study focused i) on the control of degree of polyCD functionalization of the PLLA support and on its physical and biological characterization by Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC) and cell viability, ii) on the understanding of drug/meshes interaction using mathematic model and iii) on the correlation between drug release studies in phosphate buffer saline (PBS) and microbiological evaluation of meshes and release medium against E. coli and S. aureus. All above mentioned tests highlighted the contribution of polyCD on the improved performances of the resulting antibacterial implantable material.

  13. Prolonged morphine administration alters protein expression in the rat myocardium

    PubMed Central

    2011-01-01

    Background Morphine is used in clinical practice as a highly effective painkiller as well as the drug of choice for treatment of certain heart diseases. However, there is lack of information about its effect on protein expression in the heart. Therefore, here we aimed to identify the presumed alterations in rat myocardial protein levels after prolonged morphine treatment. Methods Morphine was administered to adult male Wistar rats in high doses (10 mg/kg per day) for 10 days. Proteins from the plasma membrane- and mitochondria-enriched fractions or cytosolic proteins isolated from left ventricles were run on 2D gel electrophoresis, scanned and quantified with specific software to reveal differentially expressed proteins. Results Nine proteins were found to show markedly altered expression levels in samples from morphine-treaded rats and these proteins were identified by mass spectrometric analysis. They belong to different cell pathways including signaling, cytoprotective, and structural elements. Conclusions The present identification of several important myocardial proteins altered by prolonged morphine treatment points to global effects of this drug on heart tissue. These findings represent an initial step toward a more complex view on the action of morphine on the heart. PMID:22129148

  14. Simplified methods for the prolonged treatment of fish diseases

    USGS Publications Warehouse

    Fish, F.F.

    1939-01-01

    The prevention or control of epidemics of fish diseases by applying a disinfecting solution in a uniform concentration directly to the water supply of a fish pond or trough for a definite period of time has been exceedingly slow in development. In so far as can be determined, the original idea should be credited to. Marsh and Robinson (1910). In their work on the control of algae in fish ponds by the continuous application of dilute copper sulphate solution, administered to the inflowing water supply by means of a floating syphon, they suggested this method as a possibility in the treatment of fish diseases. Following their work, this commendable idea seems to have remained quite dormant and apparently forgotten until Hess (1930) revived it twenty or more years later. This worker found that a prolonged immersion in a dilute disinfecting bath was more efficacious in remowng fluke parasites from goldfish than was the customary short "hand dip" method. Kingsbury and Embody (1932) later adapted the idea of a prolonged treatment to running water by the use of a float valve for maintaining a constant level in a reservoir, resulting in a constant flow to the pond or trough to be treated. Shortly thereafter, Fish (1933) modified the floating syphon of Marsh and Robinson, as it was a simpler apparatus than that of Kingsbury and Embody.

  15. Influence of a Prolonged Tennis Match Play on Serve Biomechanics.

    PubMed

    Martin, Caroline; Bideau, Benoit; Delamarche, Paul; Kulpa, Richard

    2016-01-01

    The aim of this study was to quantify kinematic, kinetic and performance changes that occur in the serve throughout a prolonged tennis match play. Serves of eight male advanced tennis players were recorded with a motion capture system before, at mid-match, and after a 3-hour tennis match. Before and after each match, electromyographic data of 8 upper limb muscles obtained during isometric maximal voluntary contraction were compared to determine the presence of muscular fatigue. Vertical ground reaction forces, rating of perceived exertion, ball speed, and ball impact height were measured. Kinematic and upper limb kinetic variables were computed. The results show decrease in mean power frequency values for several upper limb muscles that is an indicator of local muscular fatigue. Decreases in serve ball speed, ball impact height, maximal angular velocities and an increase in rating of perceived exertion were also observed between the beginning and the end of the match. With fatigue, the majority of the upper limb joint kinetics decreases at the end of the match. No change in timing of maximal angular velocities was observed between the beginning and the end of the match. A prolonged tennis match play may induce fatigue in upper limb muscles, which decrease performance and cause changes in serve maximal angular velocities and joint kinetics. The consistency in timing of maximal angular velocities suggests that advanced tennis players are able to maintain the temporal pattern of their serve technique, in spite of the muscular fatigue development.

  16. Design of the INHIBIT trial: preventing inhibitors by avoiding ‘danger’, prolonging half-life and promoting tolerance

    PubMed Central

    Ragni, Margaret V; Malec, Lynn M

    2015-01-01

    Inhibitor formation is among the most serious complications of hemophilia treatment. With the US FDA licensure of the novel long-lasting recombinant factor VIII (FVIII) Fc fusion protein, Eloctate, which prolongs FVIII half-life, we propose an innovative approach to prevent inhibitor formation. In this paper, we describe a multicenter, Phase II, single-arm, 48-week trial, the INHIBIT trial, to determine if Eloctate, begun before a bleed and continued as once weekly prophylaxis, will reduce inhibitor formation in children with hemophilia A. We hypothesize that avoiding ‘danger,’ that is, immune activation by a bleed at first factor exposure and prolonging FVIII half-life will prevent inhibitors and promote FVIII-specific T-cell tolerance. If successful, this approach will suggest a new paradigm in clinical practice. PMID:25374055

  17. Ion regulatory function of the human kidney in prolonged space flights

    NASA Astrophysics Data System (ADS)

    Grigoriev, A. I.

    Ten cosmonauts, who performed 30-175-day space flights aboard Salyut-4 and Salyut-6, and over 60 test subjects who were exposed to bed rest of up to 182 days and immersion of up to 56 days, were examined. The renal excretion of potassium and calcium increased, reaching a maximum by the 4-6th weeks in prolonged space flights and simulation studies. During the load tests with potassium and calcium salt, excretion postflight was much higher than preflight. During potassium chloride load tests a positive correlation between the blood content of aldosterone and potassium excretion existed, whereas during calcium lactate load tests an increased calcium excretion was accompanied by a decrease in blood parathyroid hormone concentration. The most probable cause of the negative ion balance in weightlessness is the reduced capacity of tissues to retain electrolytes due to the decreased ion pool capacity. Different exercises have been shown to exert a beneficial effect on electrolyte metabolism.

  18. Dissemination and implementation of prolonged exposure therapy for posttraumatic stress disorder.

    PubMed

    McLean, Carmen P; Foa, Edna B

    2013-12-01

    Posttraumatic stress disorder (PTSD) is a highly prevalent, often chronic and disabling psychiatric disorder that is associated with significant adverse health and life consequences. Although several evidence-based treatments (EBTs), including Prolonged Exposure therapy (PE), have been found effective and efficacious in reducing PTSD symptomology, the majority of individuals with this disorder receive treatments of unknown efficacy. Thus, it is imperative that EBTs such as PE be made available to PTSD sufferers through widespread dissemination and implementation. We will review some of the efforts to increase the availability of PE and the common barriers to successful dissemination and implementation. We also discuss novel dissemination strategies that are harnessing technology to overcome barriers to dissemination.

  19. Protective effect of ligustrazine on lumbar intervertebral disc degeneration of rats induced by prolonged upright posture.

    PubMed

    Liang, Qian-Qian; Ding, Dao-Fang; Xi, Zhi-Jie; Chen, Yan; Li, Chen-Guang; Liu, Shu-Fen; Lu, Sheng; Zhao, Yong-Jian; Shi, Qi; Wang, Yong-Jun

    2014-01-01

    Most chronic low back pain is the result of degeneration of the lumbar intervertebral disc. Ligustrazine, an alkaloid from Chuanxiong, reportedly is able to relieve pain, suppress inflammation, and treat osteoarthritis and it has the protective effect on cartilage and chondrocytes. Therefore, we asked whether ligustrazine could reduce intervertebral disc degeneration. To determine the effect of ligustrazine on disc degeneration, we applied a rat model. The intervertebral disc degeneration of the rats was induced by prolonged upright posture. We found that pretreatment with ligustrazine for 1 month recovered the structural distortion of the degenerative disc; inhibited the expression of type X collagen, matrix metalloproteinase (MMP)-13, and MMP3; upregulated type II collagen; and decreased IL-1 β , cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) expression. In conclusion, ligustrazine is a promising agent for treating lumbar intervertebral disc degeneration disease.

  20. Enhanced cytotoxicity of melphalan by prolonged exposure to nitroimidazoles: the role of endogenous thiols

    SciTech Connect

    Roizin-Towle, L.; Hall, E.J.; Flynn, M.; Biaglow, J.E.; Varnes, M.E.

    1982-01-01

    The present study shows that a prolonged exposure of V-79 cells to a variety of nitroimidazoles (misonidazole, Ro-05-9963, Sr-2508, and MRT1-80) results in an enhanced cytotoxicity when these cells are subsequently exposed to melphalan. This process of enhanced malphalan toxicity occurred only when cells were pretreated with misonidazole under hypoxic conditions, suggesting that nitroreduction is necessary for chemosensitization as it is for increased radiosensitization. Different nitroimidazoles tested vary in the extent to which they sensitize cells to the subsequent action of melphalan. Repair from a misonidazole pretreatment is essentially complete by six hours. This study demonstrated that cysteamine could reduce the cytotoxicity of misonidazole and the enhancement of melphalan toxicity. This was an effect reversible with time and one implying similar mechanisms for the preincubation effect observed in vitro for radiation and chemotherapy agents.

  1. Prolonged Radiant Exposure of the Middle Ear during Transcanal Endoscopic Ear Surgery.

    PubMed

    Shah, Parth V; Kozin, Elliott D; Remenschneider, Aaron K; Dedmon, Matthew M; Nakajima, Hideko Heidi; Cohen, Michael S; Lee, Daniel J

    2015-07-01

    Transcanal endoscopic ear surgery (EES) provides a high-resolution, wide-field view of the middle ear compared with the conventional operating microscope, reducing the need for a postauricular incision or mastoidectomy. Our group has shown in cadaveric human temporal bone studies that radiant energy from the endoscope tip can quickly elevate temperatures of the tympanic cavity. Elevated temperatures of the middle ear are associated with acute auditory brainstem response shifts in animal models. In EES, proposed methods to decrease middle ear temperature include frequent removal of the endoscope and the use of suction to rapidly dissipate heat; however, the routine application of such cooling techniques remains unknown. Herein, we aim to quantify the duration that the tympanic cavity is typically exposed to the endoscope during routine endoscopic middle ear surgery. We find that the tympanic cavity is exposed to the endoscope without a cooling mechanism for a prolonged period of time.

  2. The Need for Self-Report Data in the Assessment of Stuttering Therapy Efficacy: Repetitions and Prolongations of Speech. The Stuttering Syndrome

    ERIC Educational Resources Information Center

    Guntupalli, Vijaya K.; Kalinowski, Joseph; Saltuklaroglu, Tim

    2006-01-01

    Background: Bloodstein reviewed hundreds of studies that investigated the efficacy of therapeutic protocols for ameliorating the stuttering syndrome. Surprisingly, almost all were effective in significantly reducing overtly perceptible behaviours such as repetitions and prolongations of speech sounds. These results seem highly improbable…

  3. Arsenic in an Alkaline AMD Treatment Sludge: Characterization and Stability Under Prolonged Anoxic Conditions

    SciTech Connect

    Beauchemin, S.; Fiset, J; Poirier, G; Ablett, J

    2010-01-01

    Lime treatment of acid mine drainage (AMD) generates large volumes of neutralization sludge that are often stored under water covers. The sludge consists mainly of calcite, gypsum and a widespread ferrihydrite-like Fe phase with several associated species of metal(loid) contaminants. The long-term stability of metal(loid)s in this chemically ill-defined material remains unknown. In this study, the stability and speciation of As in AMD sludge subjected to prolonged anoxic conditions is determined. The total As concentration in the sludge is 300 mg kg{sup -1}. In the laboratory, three distinct water cover treatments were imposed on the sludge to induce different redox conditions (100%N{sub 2}, 100%N{sub 2} + glucose, 95%N{sub 2}:5%H{sub 2}). These treatments were compared against a control of oxidized, water-saturated sludge. Electron micro-probe (EMP) analysis and spatially resolved synchrotron X-ray fluorescence (SXRF) results indicate that As is dominantly associated with Fe in the sludge. In all treatments and throughout the experiment, measured concentrations of dissolved As were less than 5 {micro}g L{sup -1}. Dissolved Mn concentration in the N{sub 2} + glucose treatment increased significantly compared to other treatments. Manganese and As K-edge X-ray absorption near edge structure spectroscopy (XANES) analyses showed that Mn was the redox-active element in the solid-phase, while As was stable. Arsenic(V) was still the dominant species in all water-covered sludges after 9 months of anoxic treatments. In contrast, Mn(IV) in the original sludge was partially reduced into Mn(II) in all water-covered sludges. The effect was most pronounced in the N{sub 2} + glucose treatment, suggesting microbial reduction. Micro-scale SXRF and XANES analysis of the treated sludge showed that Mn(II) accumulated in areas already enriched in Fe and As. Overall, the study shows that AMD sludges remain stable under prolonged anoxic conditions. External sources of chemical reductants

  4. Randomised clinical trial of the effects of prolonged-release melatonin, temazepam and zolpidem on slow-wave activity during sleep in healthy people.

    PubMed

    Arbon, Emma L; Knurowska, Malgorzata; Dijk, Derk-Jan

    2015-07-01

    Current pharmacological treatments for insomnia include benzodiazepine and non-benzodiazepine hypnotics targeting γ-aminobutyric acid (GABA)A receptors, as well as agonists of the melatonin receptors MT1 and MT2. Melatonin, temazepam and zolpidem are thought to exert their effect through different mechanisms of action, but whether this leads to differential effects on electroencephalogram (EEG) power spectra during sleep in middle-aged people is currently not known. To establish whether the effects of prolonged-release melatonin (2 mg) on the nocturnal sleep EEG are different to those of temazepam (20 mg) and zolpidem (10 mg). Sixteen healthy men and women aged 55-64 years participated in a double-blind, placebo-controlled, four-way cross-over trial. Nocturnal sleep was assessed with polysomnography and spectral analysis of the EEG. The effects of single oral doses of prolonged-release melatonin, temazepam and zolpidem on EEG slow-wave activity (SWA, 0.75-4.5 Hz) and other frequencies during nocturnal non-rapid eye movement (NREM) sleep were compared. In an entire night analysis prolonged-release melatonin did not affect SWA, whereas temazepam and zolpidem significantly reduced SWA compared with placebo. Temazepam significantly reduced SWA compared with prolonged-release melatonin. Prolonged-release melatonin only reduced SWA during the first third of the night compared with placebo. These data show that the effects of prolonged-release melatonin on the nocturnal sleep EEG are minor and are different from those of temazepam and zolpidem; this is likely due to the different mechanisms of action of the medications.

  5. Outcomes and predictors of prolonged ventilation in patients undergoing elective coronary surgery†

    PubMed Central

    Saleh, Hesham Z.; Shaw, Matthew; Al-Rawi, Omar; Yates, Jonathan; Pullan, D. Mark; Chalmers, John A.C.; Fabri, Brian M.

    2012-01-01

    OBJECTIVES Despite the seriousness of prolonged mechanical ventilation (PMV) as a postoperative complication, previously proposed risk prediction models were met with limited success. The purpose of this study was to identify perioperative variables associated with PMV in elective primary coronary bypass surgery. PMV was defined as the need for intubation and mechanical ventilation for >72 h, after completion of the operation. METHODS Between April 1997 and September 2010, 10 977 consecutive patients were retrospectively reviewed. A series of two multivariate logistic regression analyses were carried out to identify preoperative predictors of prolonged ventilation and the impact of operative variables. RESULTS PMV occurred in 215 (1.96%) patients; 119 (55.3%) of these underwent tracheostomy. At multivariate analysis, predictors included NYHA higher than class II (odds ratio [OR], 1.77; 95% confidence intervals [CI], 1.34–2.34), renal dialysis (OR, 5.5; 95% CI, 2.08–14.65), age at operation (OR, 1.04; 95% CI, 1.02–1.06), reduced FEV1 (OR, 0.99; 95% CI, 0.98–0.99), body mass index >35 kg/m2 (OR, 1.73; 95% CI, 1.14–2.63). On serial logistic regression analyses, operative variables added little to the discriminatory power of the model. Kaplan–Meier survival curves showed reduced survival among PMV patients (P < 0.001) with an improved survival in the tracheostomy subgroup. CONCLUSIONS PMV after coronary bypass is associated with a reduction in early and mid-term survival. Risk modelling for PMV remains problematic even when examining a more homogenous lower risk group. PMID:22495507

  6. Interaction of hyperthermia and heart rate on stroke volume during prolonged exercise.

    PubMed

    Trinity, Joel D; Pahnke, Matthew D; Lee, Joshua F; Coyle, Edward F

    2010-09-01

    People who become hyperthermic during exercise display large increases in heart rate (HR) and reductions in stroke volume (SV). It is not clear if the reduction in SV is due primarily to hyperthermia or if it is a secondary effect of an elevation in HR reducing ventricular filling. In the present study, the upward drift of HR during prolonged exercise was prevented by a very small dose of the β1-adrenoreceptor blocker (atenolol; βB), thus allowing SV to be compared at a given HR during normothermia and hyperthermia. Eleven men cycled for 60 min at 57% of peak O2 uptake after receiving placebo control (PL) or a low dose (0.2 mg/kg) of βB. Hyperthermia was induced by reducing heat dissipation during exercise. Four experimental conditions were studied: normothermia-PL, normothermia-βB, hyperthermia-PL, and hyperthermia-βB. Hyperthermia increased skin and core temperature by 4.3 degrees C and 0.8 degrees C (P<0.01), respectively. βB prevented HR elevation with hyperthermia: HR values were similar at minute 60 during normothermia-PL and hyperthermia-βB (155±11 and 154±13 beats/min, respectively, P=0.82). However, SV was increased by 7% during the final 20 min of exercise during hyperthermia-βB compared with normothermia-PL (treatment×time interaction, P=0.03). In conclusion, when matched for HR, mild hyperthermia increased SV during exercise. Furthermore, the reduction in SV throughout prolonged exercise under normothermic and mildly hyperthermic conditions appears to be due to the increase in HR.

  7. Cigarette smoking following a prolonged mental task exaggerates vasoconstriction in glabrous skin in habitual smokers.

    PubMed

    Uehara, Kouhei; Sone, Ryoko; Yamazaki, Fumio

    2010-12-01

    In the present study, to test the hypothesis that cigarette smoking and physical exercise induce different influences on peripheral vasomotor control after mental stress, we examined the physiological responses, including skin vasomotor responses, to smoking and exercise in six healthy smokers. The smokers performed 2 hr of mental arithmetic tasks (MT) followed by smoking or bicycle exercise (108 +/- 7W) for 10 min or a time control (i.e., rest without smoking) under thermally comfortable conditions (25 degrees C). Skin blood flow (laser-Doppler flowmetry) was monitored at glabrous (palm) and nonglabrous (forearm, forehead) sites. Cutaneous vascular conductance (CVC) was evaluated from the ratio of blood flow to mean arterial pressure (MAP). The prolonged MT increased MAP from 77.7 +/- 2.7 mmHg to 86.0 +/- 3.0 mmHg and reduced CVC in the palm by 27.4 +/- 5.6%, but did not change those in the forearm and forehead. Smoking after MT further decreased CVC in the palm, and the smoking-induced reduction in CVC persisted until 20 min after smoking. Meanwhile, CVC in the forearm and forehead transiently and minimally decreased during smoking. Exercise after MT increased CVC at the three sites, and the exercise-induced elevation of CVC in the palm persisted until 30 min after exercise. In the time control experiments, each variable remained unchanged throughout the recovery period of MT. It was suggested that smoking causes additional vasoconstriction in glabrous skin after prolonged MT, while the exercise-associated vasodilator effect counteracts the vasoconstrictor action of MT. We speculate that long-term mental stress and smoking behavior may synergistically develop chronic stress-induced vascular dysfunction, and the stress-related disorders may be reduced by habitual enforcement of moderate exercise.

  8. Impact of Prolonged Sitting on Lower and Upper Limb Micro- and Macrovascular Dilator Function

    PubMed Central

    Restaino, Robert M.; Holwerda, Seth W.; Credeur, Daniel P.; Fadel, Paul J.; Padilla, Jaume

    2016-01-01

    Sedentary behavior in the workplace and increased daily sitting time are on the rise; however, studies investigating the impact of sitting on vascular function remain limited. Herein we hypothesized that 6 hours of uninterrupted sitting would impair limb micro- and macrovascular dilator function and this impairment could be improved with a bout of walking. Resting blood flow, reactive hyperemia to 5 min cuff occlusion (microvascular reactivity) and associated FMD (macrovascular reactivity) were assessed in popliteal and brachial arteries of young men at baseline (Pre Sit) and after 6 hours of uninterrupted sitting (Post Sit). Measures were then repeated after a 10 min walk (~1000 steps). Sitting resulted in a marked reduction of resting popliteal artery mean blood flow and mean shear rate (6-hr mean shear rate, −52±8 s−1 vs. Pre Sit, p<0.05). Interestingly, reductions were also found in the brachial artery (6-hr mean shear rate, −169±41 s−1 vs. Pre Sit, p<0.05). Likewise, following 6 hours of sitting, cuff-induced reactive hyperemia was reduced in both the lower leg (−43±7% vs. Pre Sit, p<0.05) and forearm (−31±11% vs. Pre Sit, p<0.05). In contrast, popliteal, but not brachial, artery FMD was blunted with sitting. Notably, lower leg reactive hyperemia and FMD were restored after walking. Collectively, these data suggest that prolonged sitting markedly reduces lower leg micro- and macrovascular dilator function but these impairments can be fully normalized with a short bout of walking. In contrast, upper arm microvascular reactivity is selectively impaired with prolonged sitting and walking does not influence this effect. PMID:25929229

  9. Aging Mechanisms and Control. Symposium Part A - Developments in Computational Aero- and Hydro-Acoustics. Symposium Part B - Monitoring and Management of Gas Turbine Fleets for Extended Life and Reduced Costs (Les mecanismes vieillissants et le controle) (Symposium Partie A - Developpements dans le domaine de l’aeroacoustique et I’hydroacoustique numeriques) (Symposium Partie B - Le suivi et la gestion des turbomoteurs en vue du prolongement de l

    DTIC Science & Technology

    2003-02-01

    and to the Conference of National Armament Directors. It comprises a Research and Technology Board (RTB) as the highest level of national...effect was removed with mesh refinement. Nevertheless, in this test case, most likely due to the high complexity of the plate response, the mesh...of the volute in fact reduces the sound level . The likely explanation here is that the back pressure provided by the volute stabilises the flow in the

  10. Prolonging the postcomplex spike pause speeds eyeblink conditioning.

    PubMed

    Maiz, Jaione; Karakossian, Movses H; Pakaprot, Narawut; Robleto, Karla; Thompson, Richard F; Otis, Thomas S

    2012-10-09

    Climbing fiber input to the cerebellum is believed to serve as a teaching signal during associative, cerebellum-dependent forms of motor learning. However, it is not understood how this neural pathway coordinates changes in cerebellar circuitry during learning. Here, we use pharmacological manipulations to prolong the postcomplex spike pause, a component of the climbing fiber signal in Purkinje neurons, and show that these manipulations enhance the rate of learning in classical eyelid conditioning. Our findings elucidate an unappreciated aspect of the climbing fiber teaching signal, and are consistent with a model in which convergent postcomplex spike pauses drive learning-related plasticity in the deep cerebellar nucleus. They also suggest a physiological mechanism that could modulate motor learning rates.

  11. Carnitine prolongs the half-life of ethanol in broilers.

    PubMed

    Smith, M O; Cha, Y S; Sachan, D S

    1994-09-01

    The object was to determine if carnitine attenuated ethanol metabolism in broilers similar to that reported in the rats. Two groups (n = 5) of 5-week-old broilers were given for 10 days the feed with or without 0.5% L-carnitine supplement. A single oral dose of ethanol on day 8 was followed by serial blood samples which were analysed for ethanol. Another dose of ethanol was given on day 10 and 2 hr later, plasma and liver were collected and analysed for ethanol, total lipid, triglycerides and carnitine. The carnitine supplemented diet prolonged the half-life of ethanol due to attenuation of ethanol metabolism which is similar to that reported earlier in rodents. The increases in plasma and hepatic acylcarnitines indicate that supplementary carnitine lessens the load of free acyl groups in the liver by eventual oxidation or excretion.

  12. Prolonged weightlessness, reference frames and visual symmetry detection.

    PubMed

    Leone, G; de Schonen, S; Lipshits, M

    1998-01-01

    We evaluated the influence of prolonged weightlessness on the performance of three cosmonauts to bilateral symmetry detection in the course of a 15-day-long Russian-French mission CASSIOPEE 96 aboard the MIR station. We tested the influence of weightlessness on subjects' performance as a function of the retinal orientation of axis of symmetry. as a function of type of stimuli (closed versus multi-elements shapes) and as a function of visual field presentation (at fixation, left visual field. right visual field). The results indicate firstly a difference between presentation at fixation versus away of fixation. Away of fixation, no effect of microgravity on performance was shown. A hypothesis of hemispheric specialization for symmetry detection was not supported as well. At fixation, an effect of micro-gravity was shown and more interestingly, the effect was quite different as a function of type of shapes used. suggesting that symmetry detection is a multiple-stage process.

  13. Prolonged treatment of refractory status epilepticus in a child.

    PubMed

    Sahin, M; Riviello, J J

    2001-02-01

    Barbiturate anesthesia, which is commonly used for refractory status epilepticus, is an effective treatment, but with many significant complications. The relationship between the duration of this extreme therapy and the ultimate outcome of refractory status epilepticus has not been well studied. We report a 7-year-old girl who presented with refractory status epilepticus secondary to presumed encephalitis with a focal lesion on cranial magnetic resonance imaging. She was treated for 70 days with high-dose antiepileptic drugs and recovered with a residual seizure disorder. This case suggests that, if the status epilepticus is due to a reversible cause such as encephalitis, neurologic recovery may occur despite this very prolonged course of extreme therapy.

  14. Slow recovery in desert perennial vegetation following prolonged human disturbance

    USGS Publications Warehouse

    Guo, Q.

    2004-01-01

    The study shows an exceptionally long-term recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection in 1906, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of clear relationship between environment (e.g., precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery process after disturbances.

  15. Prolonged intensive dominance behavior between gray wolves, Canis lupus

    USGS Publications Warehouse

    Mech, L. David; Cluff, H. Dean

    2010-01-01

    Dominance is one of the most pervasive and important behaviors among wolves in a pack, yet its significance in free-ranging packs has been little studied. Insights into a behavior can often be gained by examining unusual examples of it. In the High Arctic near Eureka, Nunavut, Canada, we videotaped and described an unusually prolonged and intensive behavioral bout between an adult male Gray Wolf (Canis lupus) and a male member of his pack, thought to be a maturing son. With tail raised, the adult approached a male pack mate about 50 m from us and pinned and straddled this packmate repeatedly over 6.5 minutes, longer than we had ever seen in over 50 years of studying wolves. We interpreted this behavior as an extreme example of an adult wolf harassing a maturing offspring, perhaps in prelude to the offspring?s dispersal.

  16. Media Impacts on Women's Fertility Desires: A Prolonged Exposure Experiment.

    PubMed

    Knobloch-Westerwick, Silvia; Willis, Laura E; Kennard, Ashley R

    2016-06-01

    Media exposure may have implications for family planning, a public health issue of key importance. Drawing on social comparison theory and social identity theory, a prolonged exposure experiment examined whether media portrayals of women's social roles affect fertility desires among 166 American, nonstudent, never married, childless women ages 21-35 years old. After sign-up and baseline sessions, participants viewed magazine pages five days in a row. Stimuli presented women in either mother/homemaker roles, beauty ideal roles, or professional roles. Three days later, participants again indicated their number of desired children and time planned until first birth. Exposure to mother/homemaker and beauty ideal portrayals increased the number of desired children across time. Exposure to professional portrayals increased the time planned until 1st birth compared to beauty ideal portrayals-this impact was partially mediated by a shift toward more progressive gender norms (per social identity theory) and assimilation (per social comparison theory).

  17. Prolonged remission of leukemia associated with polycythemia vera.

    PubMed

    Hazani, A; Tatarsky, I; Barzilai, D

    1977-09-01

    A patient with polycythemia vera (PV) received successive treatment by phlebotomies, radioactive phosphorus, myleran and cyclophosphamide. Sixteen years after the diagnosis, he developed acute myeloblastic leukemia. A complete remission was achieved following two courses of COAP (cyclophosphamide, vincristine, Cytosine Arabinoside, and prednisone) therapy. Four months later, while still in leukemic remission, he became mildly polycythemic again and the treatment with phlebotomies and cyclophosphamide was resume. The patient has subsequently been in complete remission of leukemia for over three years and his polycythemia is controlled by small doses of cyclophosphamide. This appears to be a unique case of such a prolonged remission of leukemia in the course of PV, with a return to a mild polycythemia state.

  18. Drivers' misjudgement of vigilance state during prolonged monotonous daytime driving.

    PubMed

    Schmidt, Eike A; Schrauf, Michael; Simon, Michael; Fritzsche, Martin; Buchner, Axel; Kincses, Wilhelm E

    2009-09-01

    To investigate the effects of monotonous daytime driving on vigilance state and particularly the ability to judge this state, a real road driving study was conducted. To objectively assess vigilance state, performance (auditory reaction time) and physiological measures (EEG: alpha spindle rate, P3 amplitude; ECG: heart rate) were recorded continuously. Drivers judged sleepiness, attention to the driving task and monotony retrospectively every 20 min. Results showed that prolonged daytime driving under monotonous conditions leads to a continuous reduction in vigilance. Towards the end of the drive, drivers reported a subjectively improved vigilance state, which was contrary to the continued decrease in vigilance as indicated by all performance and physiological measures. These findings indicate a lack of self-assessment abilities after approximately 3h of continuous monotonous daytime driving.

  19. Muscle regeneration in the prolonged absence of myostatin.

    PubMed

    Wagner, Kathryn R; Liu, Xiaosong; Chang, Xiaoli; Allen, Ronald E

    2005-02-15

    Myostatin is an endogenous inhibitor of muscle conserved across diverse species. In the absence of myostatin, there is massive muscle growth in mice, cattle, and humans. Previous studies in the mdx mouse model of muscular dystrophy demonstrate that inhibiting myostatin attenuates several features of dystrophic muscle. These findings have encouraged the development of human therapies to block myostatin. However, little is known of the long-term effects on muscle of myostatin blockade. To evaluate potential sequelae from the prolonged absence of myostatin, senescent myostatin null (mstn-/-) mice were studied. Senescent mstn-/- mice continue to have normal muscle with increased mass and strength relative to controls. Muscles of senescent mstn-/- mice regenerate robustly from both chronic and acute injury. Early markers of regeneration are enhanced in the absence of myostatin, suggesting a mechanism for the attenuation of dystrophic features found in mdx mice lacking myostatin.

  20. Prolonged QT interval in a man with anorexia nervosa

    PubMed Central

    Macías-Robles, María Dolores; Perez-Clemente, Ana María; Maciá-Bobes, Carmen; Alvarez-Rueda, María Asunción; Pozo-Nuevo, Sergio

    2009-01-01

    Anorexia nervosa is an eating disorder characterized by the avoidance of food intake, which usually leads to a weight loss. Cardiac co-morbility is common and we can find sometimes a mass loss from the left ventricle, which can be seen by echocardiography. But the commonest complications are rhythm variations, typically bradycardia with a prolonged QT interval in up to a 40% of the cases, which altogether elevates ventricular tachycardia and sudden death risk. We present the case of a male who was diagnosed with anorexia nervosa and developed asthenia, a long QT interval and also a severe both hypokalaemia and hypomagnesaemia. We intend to discuss the pathogenic paths as well as prophylactic and therapeutic measures to this potentially-lethal pathology. PMID:19646241

  1. Apparent life-threatening prolonged infant apnea in Saskatchewan.

    PubMed Central

    Sunkaran, K; McKenna, A; O'Donnell, M; Ninan, A; Kasian, G; Skwarchuk, J; Bingham, W T

    1989-01-01

    Life-threatening events such as prolonged apnea and severe bradycardia are uncommon in infants. When such events occur in a family, however, the results may be disastrous. Over a period of 3 years ending June 1986, we have looked after 111 such infants aged 4 weeks to 40 weeks with a mean age of 14 weeks (male-female ratio 1.26:1). Of these infants, 33 had an identifiable cause and were treated according to the diagnoses. A structural approach to this problem yielded good results. Only 10 infants were treated with a home monitor (4 prescribed by physician and 6 by parental request). Sleep and pneumogram (polysomnogram) studies showed fewer apneic episodes with advancing age (P less than .01). Giving theophylline seemed to abolish pneumogram abnormalities. No infants died. PMID:2735034

  2. Elevated rates of prolonged grief disorder in African Americans.

    PubMed

    Goldsmith, B; Morrison, R S; Vanderwerker, L C; Prigerson, H G

    2008-01-01

    The prevalence of Prolonged Grief Disorder (PGD) in non-Whites is currently unknown. This study was performed to explore the prevalence of PGD in African Americans (AAs). Multivariable analysis of two studies of recently bereaved individuals found AAs to have significantly higher rates of PGD than Whites (21% [14 of 66] vs. 12% [55 of 471], respectively; p = 0.03). Experiencing a loved one's death as sudden or unexpected was also significantly associated with PGD over and above the effects of race/ethnicity. AAs may be at increased risk for the development of PGD. The development of effective interventions to treat PGD highlights the need to identify high-risk individuals and refer them to therapy and suggests the potential need for such therapies to adopt culturally sensitive approaches to care.

  3. PIGMENT DEPOSITION IN VISCERA ASSOCIATED WITH PROLONGED CHLORPROMAZINE THERAPY.

    PubMed

    GREINER, A C; NICOLSON, G A

    1964-09-19

    Twelve physically healthy young adult mental hospital patients died unexpectedly while on prolonged chlorpromazine therapy. Five of them had clinically obvious pigmentation of the exposed skin. Two of these had impairment of vision as well. Autopsies were performed on all 12 patients. Extensive deposits of pigment (exhibiting the physical and histochemical properties of melanin) were present in macrophages in the dermis and throughout the reticuloendothelial system, and in the parenchymal cells of internal organs. The dopa tyrosinase reaction indicated increased melanocyte activity in the epidermis.The possible mechanism of production of this pigment is discussed, and the belief is expressed that the increased melanin production is due, at least partly, to the effect of chlorpromazine on the autonomic nervous system, blocking the production of pigment-lightening factors, of which melatonin is the most important. A short outline of contemplated further investigation is given.

  4. Regulation of calcium metabolism during prolonged antiorthostatic hypokinesia

    NASA Technical Reports Server (NTRS)

    Grigoryev, A. I.; Morukov, B. V.; Dorokhova, B. R.; Rustamyan, L. A.

    1988-01-01

    Characteristics of the regulation of calcium exchange in healthy persons exposed to 182 days of antiorthostatic hypokinesia are investigated. Total calcium concentrations, ionized calcium activities and parathyroid hormone concentrations in blood serum were determined, before, during, and up to 15 days after a 182-day period of strict bed rest at a head down tilt of 4 deg; and tests of blood urine responses to a calcium lactate stress were performed to study the role of the kidneys. An increase in calcium ion activity is observed during the period of hypokinesia, while total calcium concentrations changed to a lesser degree. Plasma parathyroid hormone levels are found to significantly exceed background levels during hypokinesia and in the recovery period immediately following. Finally, the increase in calcium excretion in the urine during prolonged limitations of muscular activity is found to be connected with both an enhancement of calcium filtration and a decrease in its reabsorption in the kidneys, possibly due to changes in hormonal regulation.

  5. The biological effect of prolonged radiation and ways of selecting new anti-radiation drugs effective in this kind of radiation injury

    NASA Technical Reports Server (NTRS)

    Rogozkin, V. D.; Chertkov, K. S.; Nikolov, I.

    1974-01-01

    The basic characteristics of prolonged radiation - increased tolerance of radiation injury - are attributed to cellular kinetics; as dose rate is reduced, the population rate is not disturbed, particularly that of stem cells which makes it possible for the organism to tolerate higher radiation loads. It is concluded that this effect makes approved radio protectors, whose effect contains an established cytostatic component, unsuitable for prolonged radiation. It is better to correct the stem pool formation process by either accelerating the proliferation of cells or limiting the effect of stimuli causing cells to lose colony forming properties.

  6. Prolonged fasting increases glutathione biosynthesis in postweaned northern elephant seals.

    PubMed

    Vázquez-Medina, José Pablo; Zenteno-Savín, Tania; Forman, Henry Jay; Crocker, Daniel E; Ortiz, Rudy M

    2011-04-15

    Northern elephant seals experience prolonged periods of absolute food and water deprivation (fasting) while breeding, molting or weaning. The postweaning fast in elephant seals is characterized by increases in the renin-angiotensin system, expression of the oxidant-producing protein Nox4, and NADPH oxidase activity; however, these increases are not correlated with increased oxidative damage or inflammation. Glutathione (GSH) is a potent reductant and a cofactor for glutathione peroxidases (GPx), glutathione-S transferases (GST) and 1-cys peroxiredoxin (PrxVI) and thus contributes to the removal of hydroperoxides, preventing oxidative damage. The effects of prolonged food deprivation on the GSH system are not well described in mammals. To test our hypothesis that GSH biosynthesis increases with fasting in postweaned elephant seals, we measured circulating and muscle GSH content at the early and late phases of the postweaning fast in elephant seals along with the activity/protein content of glutamate-cysteine ligase [GCL; catalytic (GCLc) and modulatory (GCLm) subunits], γ-glutamyl transpeptidase (GGT), glutathione disulphide reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), GST and PrxVI, as well as plasma changes in γ-glutamyl amino acids, glutamate and glutamine. GSH increased two- to four-fold with fasting along with a 40-50% increase in the content of GCLm and GCLc, a 75% increase in GGT activity, a two- to 2.5-fold increase in GR, G6PDH and GST activities and a 30% increase in PrxVI content. Plasma γ-glutamyl glutamine, γ-glutamyl isoleucine and γ-glutamyl methionine also increased with fasting whereas glutamate and glutamine decreased. Results indicate that GSH biosynthesis increases with fasting and that GSH contributes to counteracting hydroperoxide production, preventing oxidative damage in fasting seals.

  7. Management of Prolonged Pulmonary Air Leaks With Endobronchial Valve Placement

    PubMed Central

    Doelken, Peter; Pupovac, Stevan; Ata, Ashar; Fabian, Tom

    2016-01-01

    Background: Prolonged pulmonary air leaks (PALs) are associated with increased morbidity and extended hospital stay. We sought to investigate the role of bronchoscopic placement of 1-way valves in treating this condition. Methods: We queried a prospectively maintained database of patients with PAL lasting more than 7 days at a tertiary medical center. Main outcome measures included duration of chest tube placement and hospital stay before and after valve deployment. Results: Sixteen patients were eligible to be enrolled from September 2012 through December 2014. One patient refused to give consent, and in 4 patients, the source of air leak could not be identified with bronchoscopic balloon occlusion. Eleven patients (9 men; mean age, 65 ± 15 years) underwent bronchoscopic valve deployment. Eight patients had postoperative PAL and 3 had a secondary spontaneous pneumothorax. The mean duration of air leak before valve deployment was 16 ± 12 days, and the mean number of implanted valves was 1.9 (median, 2). Mean duration of hospital stay before and after valve deployment was 18 and 9 days, respectively (P = .03). Patients who had more than a 50% decrease in air leak on digital monitoring had the thoracostomy tube removed within 3–6 days. There were no procedural complications related to deployment or removal of the valves. Conclusions: Bronchoscopic placement of 1-way valves is a safe procedure that could help manage patients with prolonged PAL. A prospective randomized trial with cost-efficiency analysis is necessary to better define the role of this bronchoscopic intervention and demonstrate its effect on air leak duration. PMID:27647978

  8. Dexamethasone added to lidocaine prolongs axillary brachial plexus blockade.

    PubMed

    Movafegh, Ali; Razazian, Mehran; Hajimaohamadi, Fatemeh; Meysamie, Alipasha

    2006-01-01

    Different additives have been used to prolong regional blockade. We designed a prospective, randomized, double-blind study to evaluate the effect of dexamethasone added to lidocaine on the onset and duration of axillary brachial plexus block. Sixty patients scheduled for elective hand and forearm surgery under axillary brachial plexus block were randomly allocated to receive either 34 mL lidocaine 1.5% with 2 mL of isotonic saline chloride (control group, n = 30) or 34 mL lidocaine 1.5% with 2 mL of dexamethasone (8 mg) (dexamethasone group, n = 30). Neither epinephrine nor bicarbonate was added to the treatment mixture. We used a nerve stimulator and multiple stimulations technique in all of the patients. After performance of the block, sensory and motor blockade of radial, median, musculocutaneous, and ulnar nerves were recorded at 5, 15, and 30 min. The onset time of the sensory and motor blockade was defined as the time between last injection and the total abolition of the pinprick response and complete paralysis. The duration of sensory and motor blocks were considered as the time interval between the administration of the local anesthetic and the first postoperative pain and complete recovery of motor functions. Sixteen patients were excluded because of unsuccessful blockade. The duration of surgery and the onset times of sensory and motor block were similar in the two groups. The duration of sensory (242 +/- 76 versus 98 +/- 33 min) and motor (310 +/- 81 versus 130 +/- 31 min) blockade were significantly longer in the dexamethasone than in the control group (P < 0.01). We conclude that the addition of dexamethasone to lidocaine 1.5% solution in axillary brachial plexus block prolongs the duration of sensory and motor blockade.

  9. Prolonged Remission of Psoriasis with Azathioprine Pulse Therapy

    PubMed Central

    Gupta, Ramji

    2015-01-01

    Background: Although various therapies used for the treatment of psoriasis are able to produce remission, yet relapses, a common problem, remains frequent. It was observed that treatment with intermittent high dose (IHD) and continuous low dose (CLD) azathioprine can produce prolonged and durable remission in psoriasis. Aims: To see the long term effect of azathioprine pulse therapy (APT) in psoriasis. Methods: Ten patients with psoriasis who has completed more than 5 years in remission with azathioprine pulse therapy are being taken in the study. They were given IHD azathioprine (500 mg on 3 consecutive days which is repeated every month) with CLD azathioprine (100 mg orally) daily in between IHD. The entire treatment schedule was divided into four phases. During phase I, treatment with IHD and CLD azathioprine was started and continued till complete clearance of lesions after which, patients proceeded to Phase II. In phase II, they continued to get treatment with IHD and CLD. After continued remission for a period of nine months, they entered into phase III, when the treatment with IHD was stopped, but CLD continued. If there was no recurrence after nine months of phase III treatment, CLD was also withdrawn, and patients were followed-up without any treatment (Phase IV). Results: All 10 patients completed treatment and are in remission for more than five years without any treatment. Conclusions: Out of 60 patients in phase IV, 10 patients were in continuous remission for more than five years, after all treatment had been stopped. Thus, azathioprine pulse therapy regimen produces prolonged remission in psoriasis. PMID:26288403

  10. Hydrogen Gas Ameliorates Hepatic Reperfusion Injury After Prolonged Cold Preservation in Isolated Perfused Rat Liver.

    PubMed

    Shimada, Shingo; Wakayama, Kenji; Fukai, Moto; Shimamura, Tsuyoshi; Ishikawa, Takahisa; Fukumori, Daisuke; Shibata, Maki; Yamashita, Kenichiro; Kimura, Taichi; Todo, Satoru; Ohsawa, Ikuroh; Taketomi, Akinobu

    2016-12-01

    Hydrogen gas reduces ischemia and reperfusion injury (IRI) in the liver and other organs. However, the precise mechanism remains elusive. We investigated whether hydrogen gas ameliorated hepatic I/R injury after cold preservation. Rat liver was subjected to 48-h cold storage in University of Wisconsin solution. The graft was reperfused with oxygenated buffer with or without hydrogen at 37° for 90 min on an isolated perfusion apparatus, comprising the H2 (+) and H2 (-) groups, respectively. In the control group (CT), grafts were reperfused immediately without preservation. Graft function, injury, and circulatory status were assessed throughout the perfusion. Tissue samples at the end of perfusion were collected to determine histopathology, oxidative stress, and apoptosis. In the H2 (-) group, IRI was indicated by a higher aspartate aminotransferase (AST), alanine aminotransferase (ALT) leakage, portal resistance, 8-hydroxy-2-deoxyguanosine-positive cell rate, apoptotic index, and endothelial endothelin-1 expression, together with reduced bile production, oxygen consumption, and GSH/GSSG ratio (vs. CT). In the H2 (+) group, these harmful changes were significantly suppressed [vs. H2 (-)]. Hydrogen gas reduced hepatic reperfusion injury after prolonged cold preservation via the maintenance of portal flow, by protecting mitochondrial function during the early phase of reperfusion, and via the suppression of oxidative stress and inflammatory cascades thereafter.

  11. Resting spontaneous activity in the default mode network predicts performance decline during prolonged attention workload.

    PubMed

    Gui, Danyang; Xu, Sihua; Zhu, Senhua; Fang, Zhuo; Spaeth, Andrea M; Xin, Yuanyuan; Feng, Tingyong; Rao, Hengyi

    2015-10-15

    After continuous and prolonged cognitive workload, people typically show reduced behavioral performance and increased feelings of fatigue, which are known as "time-on-task (TOT) effects". Although TOT effects are pervasive in modern life, their underlying neural mechanisms remain elusive. In this study, we induced TOT effects by administering a 20-min continuous psychomotor vigilance test (PVT) to a group of 16 healthy adults and used resting-state blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine spontaneous brain activity changes associated with fatigue and performance. Behaviorally, subjects displayed robust TOT effects, as reflected by increasingly slower reaction times as the test progressed and higher self-reported mental fatigue ratings after the 20-min PVT. Compared to pre-test measurements, subjects exhibited reduced amplitudes of low-frequency fluctuation (ALFF) in the default mode network (DMN) and increased ALFF in the thalamus after the test. Subjects also exhibited reduced anti-correlations between the posterior cingulate cortex (PCC) and right middle prefrontal cortex after the test. Moreover, pre-test resting ALFF in the PCC and medial prefrontal cortex (MePFC) predicted subjects' subsequent performance decline; individuals with higher ALFF in these regions exhibited more stable reaction times throughout the 20-min PVT. These results support the important role of both task-positive and task-negative networks in mediating TOT effects and suggest that spontaneous activity measured by resting-state BOLD fMRI may be a marker of mental fatigue.

  12. Neural and behavioural changes in male periadolescent mice after prolonged nicotine-MDMA treatment.

    PubMed

    Adeniyi, Philip A; Ishola, Azeez O; Laoye, Babafemi J; Olatunji, Babawale P; Bankole, Oluwamolakun O; Shallie, Philemon D; Ogundele, Olalekan M

    2016-02-01

    The interaction between MDMA and Nicotine affects multiple brain centres and neurotransmitter systems (serotonin, dopamine and glutamate) involved in motor coordination and cognition. In this study, we have elucidated the effect of prolonged (10 days) MDMA, Nicotine and a combined Nicotine-MDMA treatment on motor-cognitive neural functions. In addition, we have shown the correlation between the observed behavioural change and neural structural changes induced by these treatments in BALB/c mice. We observed that MDMA (2 mg/Kg body weight; subcutaneous) induced a decline in motor function, while Nicotine (2 mg/Kg body weight; subcutaneous) improved motor function in male periadolescent mice. In combined treatment, Nicotine reduced the motor function decline observed in MDMA treatment, thus no significant change in motor function for the combined treatment versus the control. Nicotine or MDMA treatment reduced memory function and altered hippocampal structure. Similarly, a combined Nicotine-MDMA treatment reduced memory function when compared with the control. Ultimately, the metabolic and structural changes in these neural systems were seen to vary for the various forms of treatment. It is noteworthy to mention that a combined treatment increased the rate of lipid peroxidation in brain tissue.

  13. Effects of prolonged abstinence from METH on the hippocampal BDNF levels, neuronal numbers and apoptosis in methamphetamine-sensitized rats.

    PubMed

    Hajheidari, Samira; Sameni, Hamid Reza; Bandegi, Ahmad Reza; Miladi-Gorji, Hossein

    2017-04-03

    Methamphetamine (METH) use is associated with neuronal damage in various regions of brain, while effects of prolonged abstinence on METH-induced damage are not quite clear. This study evaluated serum and hippocampal BDNF levels, neuronal numbers and apoptosis in METH-sensitized and abstinent rats. Rats were sensitized to METH (2mg/kg, daily/18 days, s.c.). All rats were evaluated for neuron counting, the TUNEL test and serum and hippocampal BDNF levels after 30 days of forced abstinence from METH. The results showed that increased BDNF levels in the hippocampus and serum of METH-sensitized rats returned to control level after 30 days of abstinence. The number of neurons in the DG and CA1 of hippocampus and also, the total hippocampal perimeter and area in METH-sensitized rats were significantly lower than the saline rats. While, the number of neurons was not significantly increased in the hippocampus after prolonged abstinence from METH. Also, METH-sensitized rats showed a significant increase in TUNEL-positive cells, whereas METH-abstinent rats showed a slight but significant decrease in TUNEL-positive cells in the DG and CA3 of hippocampus. These results suggest that despite the reduction in BDNF levels, reducing the number of neurons, perimeter and area of the hippocampus were stable after abstinence. Thus, the degenerative effects of METH have been sustained even after prolonged abstinence in the hippocampus.

  14. Effect of N-acetyl-l-cysteine on insulin resistance caused by prolonged free fatty acid elevation.

    PubMed

    Pereira, Sandra; Shah, Anu; George Fantus, I; Joseph, Jamie W; Giacca, Adria

    2015-04-01

    Circulating free fatty acids (FFAs) are elevated in obesity and cause insulin resistance. The objective of the current study was to determine whether the antioxidant N-acetyl-l-cysteine (NAC) prevented hepatic and peripheral insulin resistance caused by prolonged elevation of plasma FFAs. Chronically cannulated Wistar rats received saline (SAL), Intralipid plus heparin (IH), IH plus NAC, or NAC i.v. infusion for 48 h. Insulin sensitivity was determined using the hyperinsulinemic-euglycemic clamp with tritiated glucose tracer. IH induced hepatic and peripheral insulin resistance (P<0.05). NAC co-infusion did not prevent insulin resistance in the liver, although it was able to prevent peripheral insulin resistance. Prolonged IH infusion did not appear to induce oxidative stress in the liver because hepatic content of protein carbonyl, malondialdehyde, and reduced to oxidized glutathione ratio did not differ across treatment groups. In alignment with our insulin sensitivity results, IH augmented skeletal muscle protein carbonyl content and this was prevented by NAC co-infusion. Taken together, our results indicate that oxidative stress mediates peripheral, but not hepatic, insulin resistance resulting from prolonged plasma FFA elevation. Thus, in states of chronic plasma FFA elevation, such as obesity, antioxidants may protect against peripheral but not hepatic insulin resistance.

  15. Aspects of Decision-Making for Risk Reduction during the Prolonged Earthquake Sequence in Canterbury, New Zealand

    NASA Astrophysics Data System (ADS)

    Wein, A. M.; Potter, S.; Becker, J.; Ratliff, J. L.; Hudson-Doyle, E.

    2014-12-01

    An earthquake sequence is a prolonged natural hazard event. Scientists can dynamically forecast aftershock frequency within bounds of uncertainty. We examine how this capability can be used in decision-making to reduce risk during a period of heightened seismicity. We draw from experience of the Canterbury earthquake sequence initiated by a magnitude 7.1 mainshock on September 4, 2010 near the city of Christchurch, a population of 370,000. The sequence impacted the built, economic, social and natural environments of the Canterbury region. We study the use of aftershock forecasts in decision-making across the roles of policy makers, emergency managers and responders, critical infrastructure providers, insurers, communication officers, scientists, and the public. We held focus groups and interviews involving 53 participants using a semi-structured message centered approach in May and June of 2013. Transcripts from the focus groups and interviews were thematically coded using qualitative analysis. Responses to a pre-questionnaire suggested that aftershock information for decision-making increases slightly in importance throughout the four phases of a disaster - mitigation, preparedness, response and recovery. We summarize our findings from this research, including the use and barriers to the use of aftershock forecasts in decision-making across the disaster phases by roles conflicts of interest that arise in the decision-making hierarchy challenges with providing and using forecasts during a prolonged event. Finally, we reflect on implications for Operational Earthquake Forecasting and how our findings may be generalized to other prolonged hazards.

  16. Prolonged Diuretic Activity and Calcium-Sparing Effect of Tropaeolum majus: Evidence in the Prevention of Osteoporosis

    PubMed Central

    Barboza, Lorena Neris; Prando, Thiago Bruno Lima; Dalsenter, Paulo Roberto; Gasparotto, Francielly Mourão; Gasparotto, Francielli; Jacomassi, Ezilda; Araújo, Valdinei de Oliveira; Lourenço, Emerson Luiz Botelho; Gasparotto Junior, Arquimedes

    2014-01-01

    Although several studies indicate high effectiveness in the use of the hydroethanolic extract from Tropaeolum majus (HETM) as a diuretic, the impact of its prolonged use in the presence of low estrogen levels remains unclear. Thus, the aim of this study was to investigate the diuretic effects of prolonged administration of HETM in ovariectomized rats and their interrelationship between calcium excretion and bone turnover. Forty-two female Wistar rats were ovariectomized (OVX) and treated orally with different doses of HETM (3, 30, and 300 mg/kg) for 4 weeks. On the first day of treatment and at weekly intervals for four weeks the diuretic activity was evaluated. Electrolyte concentrations and creatinine levels were estimated from urine sample of each rat. The serum lipids, urea, creatinine, and osteocalcin were also measured at the end of the experiment. The data revealed that the HETM was able to sustain its diuretic effect after prolonged treatment. Moreover, its use has not affected the urinary calcium or potassium excretion, reduces lipid levels, and maintains osteocalcin levels similarly to untreated rats. These findings support the potential of HETM as a candidate to be used in clinical conditions in which the renal loss of calcium is not desired. PMID:25028592

  17. Mixing tests: diagnostic aides in the investigation of prolonged prothrombin times and activated partial thromboplastin times.

    PubMed

    Kershaw, Geoffrey; Orellana, Daniel

    2013-04-01

    Mixing tests are a relatively simple procedure used in the hemostasis laboratory as a first-line investigation into the cause of an abnormal screening test, typically a prolonged activated partial thromboplastin time and/or a prolonged prothrombin time. The mixing test involves combining the test plasma with normal plasma, then repeating the screening test on the mixture to assess whether the clotting time becomes normal or remains prolonged. The primary purpose of a mixing test is to guide further investigations. When mixing test results "normalize," this suggests the test plasma is deficient in clotting factor(s) and thus specific factor assays can be performed to determine which are reduced. When the mixing test result does not "normalize," this suggests the presence of an inhibitor or other type of interference (e.g., the presence of an anticoagulant such as high-dose heparinoids), and so the laboratory needs to determine if this is a lupus anticoagulant or a specific coagulation factor inhibitor, or another type of inhibitor. Because these follow-up investigations are more costly and time-consuming than the basic screening tests, the appropriate performance and interpretation of mixing tests is advantageous for the laboratory. Moreover, the correct laboratory approach is also clinically relevant, as patient management is ultimately affected, and an incorrect interpretation may lead to inappropriate therapies being established. Components of a mixing test that can influence result interpretation include the sensitivity of the used screening reagents to various factor deficiencies and inhibitors, the source or composition of the normal plasma, and the setting of cutoffs for the formula used in expressing mixing test results. Numerous and differing criteria for mixing test interpretation have been suggested historically, which can lead to confusion as to which approach is the most appropriate. The use of differing criteria will also lead to differing

  18. Heavy strength training improves running and cycling performance following prolonged submaximal work in well-trained female athletes.

    PubMed

    Vikmoen, Olav; Rønnestad, Bent R; Ellefsen, Stian; Raastad, Truls

    2017-03-01

    The purpose of this study was to investigate the effects of adding heavy strength training to female duathletes' normal endurance training on both cycling and running performance. Nineteen well-trained female duathletes (VO2max cycling: 54 ± 3 ml∙kg(-1)∙min(-1), VO2max running: 53 ± 3 ml∙kg(-1)∙min(-1)) were randomly assigned to either normal endurance training (E, n = 8) or normal endurance training combined with strength training (E+S, n = 11). The strength training consisted of four lower body exercises [3 × 4-10 repetition maximum (RM)] twice a week for 11 weeks. Running and cycling performance were assessed using 5-min all-out tests, performed immediately after prolonged periods of submaximal work (3 h cycling or 1.5 h running). E+S increased 1RM in half squat (45 ± 22%) and lean mass in the legs (3.1 ± 4.0%) more than E Performance during the 5-min all-out test increased in both cycling (7.0 ± 4.5%) and running (4.7 ± 6.0%) in E+S, whereas no changes occurred in E The changes in running performance were different between groups. E+S reduced oxygen consumption and heart rate during the final 2 h of prolonged cycling, whereas no changes occurred in E No changes occurred during the prolonged running in any group. Adding strength training to normal endurance training in well-trained female duathletes improved both running and cycling performance when tested immediately after prolonged submaximal work.

  19. Cesium-induced QT-interval prolongation in an adolescent.

    PubMed

    O'Brien, Catherine E; Harik, Nada; James, Laura P; Seib, Paul M; Stowe, Cindy D

    2008-08-01

    Alternative medicine is becoming increasingly popular, especially with terminally ill patients. Most alternative remedies have not been adequately studied or proven effective for the diseases for which they are promoted. In the worst cases, these therapies are harmful. We describe a 16-year-old girl with metastatic hepatocellular carcinoma who experienced cesium-induced QT-interval prolongation after the start of a cesium chloride-based alternative treatment regimen. She had received seven courses of chemotherapy, with a cumulative doxorubicin dose of 500 mg/m(2) over 5 months, resulting in minimal tumor regression. Against the advice of her oncologist, she abandoned traditional therapy and started an alternative regimen that included cesium chloride supplements. Two weeks later, the patient went to a local emergency department after experiencing two brief syncopal episodes. An electrocardiogram revealed occasional premature ventricular contractions, a QTc interval of 683 msec (normal range for females 450-460 msec), and R on T phenomenon. She was admitted to the hospital and later experienced monomorphic ventricular tachycardia, which resolved spontaneously. Lidocaine therapy was started, and the patient was transferred to a cardiac intensive care unit at our hospital. Her plasma cesium level was 2400 microg/dl (normal < 1 microg/dl), and her family was told to stop her alternative treatment regimen. On hospital day 5, as no additional arrhythmias had occurred, lidocaine was discontinued. Two days later, the patient's QTc interval had decreased to 546 msec, and she was discharged home. Two months later, at a follow-up visit, her serum cesium level was 1800 microg/dl, and her QTc interval was 494 msec. According to the Naranjo adverse drug reaction probability scale, cesium was the probable cause of the patient's arrhythmia. In animal models, cesium chloride has induced cardiac arrhythmias, including torsade de pointes. It inhibits delayed rectifier potassium

  20. Calcium Imaging of AM Dyes Following Prolonged Incubation in Acute Neuronal Tissue

    PubMed Central

    Morley, John W.; Tapson, Jonathan; Breen, Paul P.; van Schaik, André

    2016-01-01

    Calcium-imaging is a sensitive method for monitoring calcium dynamics during neuronal activity. As intracellular calcium concentration is correlated to physiological and pathophysiological activity of neurons, calcium imaging with fluorescent indicators is one of the most commonly used techniques in neuroscience today. Current methodologies for loading calcium dyes into the tissue require prolonged incubation time (45–150 min), in addition to dissection and recovery time after the slicing procedure. This prolonged incubation curtails experimental time, as tissue is typically maintained for 6–8 hours after slicing. Using a recently introduced recovery chamber that extends the viability of acute brain slices to more than 24 hours, we tested the effectiveness of calcium AM staining following long incubation periods post cell loading and its impact on the functional properties of calcium signals in acute brain slices and wholemount retinae. We show that calcium dyes remain within cells and are fully functional >24 hours after loading. Moreover, the calcium dynamics recorded >24 hrs were similar to the calcium signals recorded in fresh tissue that was incubated for <4 hrs. These results indicate that long exposure of calcium AM dyes to the intracellular cytoplasm did not alter the intracellular calcium concentration, the functional range of the dye or viability of the neurons. This data extends our previous work showing that a custom recovery chamber can extend the viability of neuronal tissue, and reliable data for both electrophysiology and imaging can be obtained >24hrs after dissection. These methods will not only extend experimental time for those using acute neuronal tissue, but also may reduce the number of animals required to complete experimental goals. PMID:27183102

  1. Prolonged stays in hospital acute geriatric care units: identification and analysis of causes.

    PubMed

    Parent, Vivien; Ludwig-Béal, Stéphanie; Sordet-Guépet, Hélène; Popitéan, Laura; Camus, Agnès; Da Silva, Sofia; Lubrano, Anne; Laissus, Frederick; Vaillard, Laurence; Manckoundia, Patrick

    2016-06-01

    In France, the population of very old frail patients, who require appropriate high-quality care, is increasing. Given the current economic climate, the mean duration of hospitalization (MDH) needs to be optimized. This prospective study analyzed the causes of prolonged hospitalization in an acute geriatric care unit. Over 6 months, all patients admitted to the target acute geriatric care unit were included and distributed into two groups according to a threshold stay of 14 days: long MDH group (LMDHG) and short MDH group (SMDHG). These two groups were compared. 757 patients were included. The LMDHG comprised 442 with a mean age of 86.7 years, of whom 67.65% were women and the SMDHG comprised 315 with a mean age of 86.6 years, of whom 63.2% were women. The two groups were statistically similar for age, sex, living conditions at home (alone or not, help), medical history and number of drugs. Patients in the LMDHG were more dependent (p=0.005), and were more likely to be hospitalized for social reasons (p=0.024) and to have come from their homes (p=0.011) than those in the SMDHG. The reasons for the prolonged stay, more frequent in the LMDHG than the SMDHG (p<0.05), were principally: waiting for imaging examinations, medical complications, and waiting for discharge solutions, assistance from social workers and/or specialist consultations. In order to reduce the MDH in acute geriatric care unit, it is necessary to consider the particularities of the patients who are admitted, their medico-socio-psychological management, access to technical facilities/consultations and post-discharge accommodation.

  2. Using gait parameters to detect fatigue and responses to ice slurry during prolonged load carriage.

    PubMed

    Tay, Cheryl S; Lee, Jason K W; Teo, Ya S; Foo, Phildia Q Z; Tan, Pearl M S; Kong, Pui W

    2016-01-01

    This study examined (1) if changes in gait characteristics could indicate the exertional heat stress experienced during prolonged load carriage, and (2) if gait characteristics were responsive to a heat mitigation strategy. In an environmental chamber replicating tropical climatic conditions (ambient temperature 32°C, 70% relative humidity), 16 males aged 21.8 (1.2) years performed two trials of a work-rest cycle protocol consisting two bouts of 4-km treadmill walks with 30-kg load at 5.3km/h separated by a 15-min rest period. Ice slurry (ICE) or room temperature water (29°C) as a control (CON) was provided in 200-ml aliquots. The fluids were given 10min before the start, at the 15(th) and 30(th) min of each work cycle, and during each rest period. Spatio-temporal gait characteristics were obtained at the start and end of each work-rest cycle using a floor-based photocell system (OptoGait) and a high-speed video camera at 120Hz. Repeated-measure analysis of variance (trial×time) showed that with time, step width decreased (p=.024) while percent crossover steps increased (p=.008) from the 40(th) min onwards. Reduced stance time variability (-11.1%, p=.029) step width variability (-8.2%, p=.001), and percent crossover step (-18.5%, p=.010) were observed in ICE compared with CON. No differences in step length and most temporal variables were found. In conclusion, changes in frontal plane gait characteristics may indicate exertional heat stress during prolonged load carriage, and some of these changes may be mitigated with ice slurry ingestion.

  3. The Presence or Absence of QTc Prolongation in Buprenorphine-Naloxone Among Youth with Opioid Dependence

    PubMed Central

    Poole, Sabrina A.; Pecoraro, Anna; Subramaniam, Geetha; Woody, George; Vetter, Victoria L

    2015-01-01

    Objective To evaluate buprenorphine-naloxone effects on the QTc in youth with opioid dependence. Buprenorphine is a partial agonist that is an effective treatment for opioid dependence. Compared to methadone it has a lower risk of QTc prolongation in adults but is less well studied in youth. It may also reduce the risk for torsades de pointes (TdP) an uncommon variant of polymorphic ventricular tachycardia, that can result in syncope, ventricular fibrillation, and sudden death. Methods Secondary analysis of ECG data from 95 subjects who participated in a multi-site trial for youth with opioid dependence. Subjects were randomized to a 2-week (DETOX), or a 12-week course of buprenorphine-naloxone (BUP). 12-lead ECGs were done at baseline, weeks 4 and 12, and QTc intervals were hand measured and calculated using Bazett's formula. Increases > 60 milliseconds (ms) were considered clinically significant, and readings > 450 ms (males) and 470 ms (females) indicated a prolonged QTc. Results Mean QTc intervals were higher for BUP than DETOX participants at baseline, week 4, and week 12 (p = 0.045), and females had longer mean QTc intervals than males (p < 0.0005). Variations in QTc intervals were observed in some, however none were above 500 ms, the level at which risk for TdP becomes more significant. Conclusion In this randomized trial, the mean QTc at baseline, before randomization, was higher in BUP than DETOX patients. Minimal changes in the QTc were seen at 4 and 12-weeks in a few patients in both groups. There was no evidence that buprenorphine-naloxone alone increased the QTc to a level that increased the risk for TdP. PMID:26690291

  4. Prolonged space flight-induced alterations in the structure and function of human skeletal muscle fibres

    PubMed Central

    Fitts, R H; Trappe, S W; Costill, D L; Gallagher, P M; Creer, A C; Colloton, P A; Peters, J R; Romatowski, J G; Bain, J L; Riley, D A

    2010-01-01

    The primary goal of this study was to determine the effects of prolonged space flight (∼180 days) on the structure and function of slow and fast fibres in human skeletal muscle. Biopsies were obtained from the gastrocnemius and soleus muscles of nine International Space Station crew members ∼45 days pre- and on landing day (R+0) post-flight. The main findings were that prolonged weightlessness produced substantial loss of fibre mass, force and power with the hierarchy of the effects being soleus type I > soleus type II > gastrocnemius type I > gastrocnemius type II. Structurally, the quantitatively most important adaptation was fibre atrophy, which averaged 20% in the soleus type I fibres (98 to 79 μm diameter). Atrophy was the main contributor to the loss of peak force (P0), which for the soleus type I fibre declined 35% from 0.86 to 0.56 mN. The percentage decrease in fibre diameter was correlated with the initial pre-flight fibre size (r = 0.87), inversely with the amount of treadmill running (r = 0.68), and was associated with an increase in thin filament density (r = 0.92). The latter correlated with reduced maximal velocity (V0) (r = −0.51), and is likely to have contributed to the 21 and 18% decline in V0 in the soleus and gastrocnemius type I fibres. Peak power was depressed in all fibre types with the greatest loss (∼55%) in the soleus. An obvious conclusion is that the exercise countermeasures employed were incapable of providing the high intensity needed to adequately protect fibre and muscle mass, and that the crew's ability to perform strenuous exercise might be seriously compromised. Our results highlight the need to study new exercise programmes on the ISS that employ high resistance and contractions over a wide range of motion to mimic the range occurring in Earth's 1 g environment. PMID:20660569

  5. Autonomic cardiovascular and respiratory control during prolonged spaceflights aboard the International Space Station.

    PubMed

    Baevsky, Roman M; Baranov, Victor M; Funtova, Irina I; Diedrich, André; Pashenko, Andrey V; Chernikova, Anja G; Drescher, Jürgen; Jordan, Jens; Tank, Jens

    2007-07-01

    Impaired autonomic control represents a cardiovascular risk factor during long-term spaceflight. Little has been reported on blood pressure (BP), heart rate (HR), and heart rate variability (HRV) during and after prolonged spaceflight. We tested the hypothesis that cardiovascular control remains stable during prolonged spaceflight. Electrocardiography, photoplethysmography, and respiratory frequency (RF) were assessed in eight male cosmonauts (age 41-50 yr, body-mass index of 22-28 kg/m2) during long-term missions (flight lengths of 162-196 days). Recordings were made 60 and 30 days before the flight, every 4 wk during flight, and on days 3 and 6 postflight during spontaneous and controlled respiration. Orthostatic testing was performed pre- and postflight. RF and BP decreased during spaceflight (P < 0.05). Mean HR and HRV in the low- and high-frequency bands did not change during spaceflight. However, the individual responses were different and correlated with preflight values. Pulse-wave transit time decreased during spaceflight (P < 0.05). HRV reached during controlled respiration (6 breaths/min) decreased in six and increased in one cosmonaut during flight. The most pronounced changes in HR, BP, and HRV occurred after landing. The decreases in BP and RF combined with stable HR and HRV during flight suggest functional adaptation rather than pathological changes. Pulse-wave transit time shortening in our study is surprising and may reflect cardiac output redistribution in space. The decrease in HRV during controlled respiration (6 breaths/min) indicates reduced parasympathetic reserve, which may contribute to postflight disturbances.

  6. Prolongation of Relaxation Time in Extraocular Muscles With Brain Derived Neurotrophic Factor in Adult Rabbit

    PubMed Central

    Nelson, Krysta R.; Stevens, Shanlee M.; McLoon, Linda K.

    2016-01-01

    Purpose We tested the hypothesis that short-term treatment with brain derived neurotrophic factor (BDNF) would alter the contractile characteristics of rabbit extraocular muscle (EOM). Methods One week after injections of BDNF in adult rabbit superior rectus muscles, twitch properties were determined in treated and control muscles in vitro. Muscles were also examined for changes in mean cross-sectional areas, neuromuscular junction size, and percent of myofibers expressing specific myosin heavy chain isoforms, and sarcoendoplasmic reticulum calcium ATPases (SERCA) 1 and 2. Results Brain derived neurotrophic factor–treated muscles had prolonged relaxation times compared with control muscles. Time to 50% relaxation, time to 100% relaxation, and maximum rate of relaxation were increased by 24%, 27%, and 25%, respectively. No significant differences were seen in time to peak force, twitch force, or maximum rate of contraction. Brain derived neurotrophic factor treatment significantly increased mean cross-sectional areas of slow twitch and tonic myofibers, with increased areas ranging from 54% to 146%. Brain derived neurotrophic factor also resulted in an increased percentage of slow twitch myofibers in the orbital layers, ranging from 54% to 77%, and slow-tonic myofibers, ranging from 44% to 62%. No significant changes were seen SERCA1 or 2 expression or in neuromuscular junction size. Conclusions Short-term treatment with BDNF significantly prolonged the duration and rate of relaxation time and increased expression of both slow-twitch and slow-tonic myosin-expressing myofibers without changes in neuromuscular junctions or SERCA expression. The changes induced by BDNF treatment might have potential therapeutic value in dampening/reducing uncontrolled eye oscillations in nystagmus. PMID:27802489

  7. Role of latency jittering correction in motion-onset VEP amplitude decay during prolonged visual stimulation.

    PubMed

    Kremláček, J; Hulan, M; Kuba, M; Kubová, Z; Langrová, J; Vít, F; Szanyi, J

    2012-06-01

    Visual evoked potentials to motion-onset stimulation (M-VEPs) gradually attenuate in amplitude during examination. The observed decline in averaged responses can be caused by decreases in single response magnitudes and/or increased variability in a response delays, that is, latency jittering. To illuminate the origins of the suppression of M-VEPs during stimuli repetition, we used correlation technique to estimate an upper bound of possible latency jittering of single sweeps and we evaluated the effect of its correction on the amplitudes of three M-VEP dominant peaks P1, N2 and P3. During prolonged visual motion stimulation, the variability of corrective latency shifts in the occipital region increased (r = 0.35: 0.44) and the number of single responses corresponding to the average curve declined in occipital and parietal derivations (r = -0.48: -0.62). While the P1 peak amplitude did not exhibit any time-specific behaviour, the N2 amplitude exhibited a significant decay of 29.4% that was partially reduced to 16.6% in the central occipital derivation by the latency jitter and non-correspondence corrections. The strongest attenuation (32.7%) was observed in the P3 amplitude and was less sensitive to the corrections, dropping only to 27.9%. The main part of the response suppression to repeated motion stimulation was caused by amplitude drop and represents non-stationary process that likely correspond to a fatigue model. The rise of variability in latency jitter correction and the reduction in single responses correlated with the M-VEP were significant factors associated with prolonged motion stimulation. The relation of these parameters to a hypothetical veridical response is ambiguous and can be caused by a time shift of the response or by a change of signal-to-noise ratio. Using selective averaging and latency jitter correction, the effect of response suppression was partially removed.

  8. Effects of ropinirole prolonged-release on sleep disturbances and daytime sleepiness in Parkinson disease.

    PubMed

    Dusek, Petr; Busková, Jitka; Růzicka, Evzen; Majerová, Veronika; Srp, Antonín; Jech, Robert; Roth, Jan; Sonka, Karel

    2010-07-01

    This study evaluated the effects of ropinirole prolonged-release (RPR) in comparison with ropinirole immediate-release (RIR) on sleep-related disorders in Parkinson disease (PD).Thirty-three PD patients (aged 62.5 [SD, 8] years; PD duration, 9 [SD, 4] years) were evaluated on a stable dose of RIR and 5 to 13 weeks after switch to the closest possible dose of RPR. The following questionnaires were administered: Epworth Sleepiness Scale, PD Sleep Scale, Pittsburgh Sleep Quality Index, REM Sleep Behavior Disorder Screening Questionnaire, and PD Questionnaire 39. We further monitored the occurrence of restless legs syndrome and sleep attacks (SAs). Motor disability was evaluated by PD diary and by Unified Parkinson Disease Rating Scale part 3 on medication (ON) and after medication withdrawal (OFF). In 8 patients with marked subjective sleep disturbance, polysomnography, and multiple sleep latency test were performed.After switching to RPR, there was an improvement in PD Sleep Scale (94.9 [SD, 23] vs 102.2 [SD, 27]; P < 0.05 corrected), Pittsburgh Sleep Quality Index (7.2 [SD, 3] vs 5.8 [SD, 3]; P < 0.05 corrected), Epworth Sleepiness Scale (14.1 [SD, 5] vs 12.0 [SD, 6]; P < 0.05 corrected) and Unified Parkinson Disease Rating Scale part 3 in the ON state (20.9 [SD, 10] 10 vs 17.6 [SD, 10]; P < 0.05 corrected). Thirteen patients reported disappearance of SAs on RPR. Polysomnography and multiple sleep latency test showed no changes in a subgroup of 8 patients after the switch to RPR.Ropinirole prolonged-release compared with RIR improved subjective quality of sleep, reduced daytime sleepiness, and led to disappearance of SAs in some patients possibly due to a more stable plasma level of ropinirole.

  9. Role of QT interval prolongation in the creation of spiral wave type reentry.

    PubMed

    Shibata, N; Watanabe, H; Sakuma, I; Kodama, I; Niwa, R; Fukui, Y; Toyama, J; Hosoda, S

    1997-01-01

    The inducibility of reentry was compared for four QT patterns in a heart conduction simulation model. Local (L) and gradual (G) QT prolongation models are more susceptible to reentry induction than the no (N) QT prolongation model (reentry induced episodes for N, L, and G numbered 90, 120, and 122, respectively). This increased vulnerability was diminished when the QT interval was prolonged at all simulation sites (reentry induced episodes for the diffuse QT prolongation model, D model, numbered 82). Decreased QT dispersion might be important for the prevention of reentry induction regardless of whether the QT interval is increased.

  10. Adhesive polydopamine coated avermectin microcapsules for prolonging foliar pesticide retention.

    PubMed

    Jia, Xin; Sheng, Wen-bo; Li, Wei; Tong, Yan-bin; Liu, Zhi-yong; Zhou, Feng

    2014-11-26

    In this work, we report a conceptual strategy for prolonging foliar pesticide retention by using an adhesive polydopamine (PDA) microcapsule to encapsulate avermectin, thereby minimizing its volatilization and improving its residence time on crop surfaces. Polydopamine coated avermectin (Av@PDA) microcapsules were prepared by emulsion interfacial-polymerization and characterized by Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, field-emission scanning electron microscope, and transmission electron microscopy. The in situ synthesis route confers Av@PDA microcapsules with remarkable avermectin loading ability of up to 66.5% (w/w). Kinetic study of avermectin release demonstrated that Av@PDA microcapsules exhibit sustained- and controlled-release properties. The adhesive property of Av@PDA microcapsules on different surfaces was verified by a comparative study between Av@PDA and passivated Av@SiO2 and Av@PDA@SiO2 capsules with silica shell. Moreover, PDA shell could effectively shield UV irradiation and so protect avermectin from photodegradation, making it more applicable for foliar spraying. Meanwhile, it is determinated that Av@PDA microcapsules have good mechanical stability property.

  11. Exercise as a countermeasure for physiological adaptation to prolonged spaceflight

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    1996-01-01

    Exercise represents the primary countermeasure used during spaceflight to maintain or restore maximal aerobic capacity (VO2max), musculoskeletal structure, and orthostatic function. However, no single exercise or combination of prescriptions has proven entirely effective in restoring cardiovascular and musculoskeletal functions to preflight levels following prolonged spaceflight. As human spaceflight exposures increase in duration, assessment and development of various effective exercise-based protective procedures become paramount. This must involve improvement in specific countermeasure prescription as well as development of additional approaches that will allow space travelers greater flexibility and medical safety during long flights. Effective exercise prescription will be based on identification of basic physiological stimuli that maintain normal function in terrestrial gravity and understanding of how specific combinations of exercise characteristics e.g., duration, frequency, intensity, mode) can mimic these stimuli and affect the overall process of adaptation to microgravity. This can be accomplished only with greater emphasis of research on ground-based experiments. Future attention must be directed to improving exercise compliance while minimizing both crew time and the impact of the exercise on life-support resources.

  12. Significant prolongation of segmental pancreatic allograft survival in two species

    SciTech Connect

    Du Toit, D.F.; Heydenrych, J.J.

    1988-06-01

    A study was conducted to assess the suppression of segmental pancreatic allograft rejection by cyclosporine (CSA) alone in baboons and dogs, and subtotal marrow irradiation (TL1) alone and TL 1 in combination with CSA in baboons. Total pancreatectomy in the dog and primate provided a reliable diabetic model, induced an absolute deficiency of insulin and was uniformly lethal if not treated. Continuous administration of CSA in baboons resulted in modest allograft survival. As in baboons, dogs receiving CSA 25 mg/kg/d rendered moderate graft prolongation but a dose of 40 mg/kg/d resulted in significant graft survival (greater than 100 days) in 5 of 8 allograft recipients. Irradiation alone resulted in minimal baboon pancreatic allograft survival of 20 baboons receiving TL1 1,000 rad and CSA, 3 had graft survival greater than of 100 days. Of 15 baboons receiving TL1 800 rad and CSA, 6 had graft survival of greater than 100 days. In conclusion, CSA administration in dogs and TL1 in combination with CSA in baboons resulted in highly significant segmental pancreatic allograft survival.

  13. Examining potential contraindications for prolonged exposure therapy for PTSD

    PubMed Central

    van Minnen, Agnes; Harned, Melanie S.; Zoellner, Lori; Mills, Katherine

    2012-01-01

    Although prolonged exposure (PE) has received the most empirical support of any treatment for post-traumatic stress disorder (PTSD), clinicians are often hesitant to use PE due to beliefs that it is contraindicated for many patients with PTSD. This is especially true for PTSD patients with comorbid problems. Because PTSD has high rates of comorbidity, it is important to consider whether PE is indeed contraindicated for patients with various comorbid problems. Therefore, in this study, we examine the evidence for or against the use of PE with patients with problems that often co-occur with PTSD, including dissociation, borderline personality disorder, psychosis, suicidal behavior and non-suicidal self-injury, substance use disorders, and major depression. It is concluded that PE can be safely and effectively used with patients with these comorbidities, and is often associated with a decrease in PTSD as well as the comorbid problem. In cases with severe comorbidity, however, it is recommended to treat PTSD with PE while providing integrated or concurrent treatment to monitor and address the comorbid problems. PMID:22893847

  14. Predictors of Prolonged Mechanical Ventilation after Open Heart Surgery

    PubMed Central

    Totonchi, Ziae; Baazm, Farah; Chitsazan, Mitra; Seifi, Somayeh; Chitsazan, Mandana

    2014-01-01

    Introduction: Due to the importance of prolonged mechanical ventilation (PMV) as a postoperative complication, predicting "high-risk" patients by identifying predisposing risk factors is of important issue. The present study was aimed to identify perioperative variables associated with PMV in patients undergoing open heart surgery. Methods: A total of 743 consecutive patients, American Society of Anesthesiologists (ASA) physical status class III, who were scheduled to undergo open heart surgery using cardiopulmonary bypass were included in this observational study. Perioperative variables were compared between the patients with and without PMV, as defined by an extubation time of >48 h. Results: PMV occurred in 45 (6.1%) patients. On univariate analysis, pre-operative variables; including gender, history of chronic obstructive pulmonary disease (COPD); chronic kidney disease and endocarditis, intra-operative variables; including type of surgery, operation time, pump time, transfusion in operating room and postoperative variables; including bleeding and inotrope-dependency were significantly different between patients with and without PMV (all P<0.001, except for COPD and transfusion in operating room; P=0.004 and P=0.017, respectively). Conclusion: Our findings reinforce that risk stratification for predicting delayed extubation should be an important aspect of preoperative clinical evaluation in all anesthesiology settings. PMID:25610551

  15. Catecholaminergic effects of prolonged head-down bed rest

    NASA Technical Reports Server (NTRS)

    Goldstein, D. S.; Vernikos, J.; Holmes, C.; Convertino, V. A.

    1995-01-01

    Prolonged head-down bed rest (HDBR) provides a model for examining responses to chronic weightlessness in humans. Eight healthy volunteers underwent HDBR for 2 wk. Antecubital venous blood was sampled for plasma levels of catechols [norepinephrine (NE), epinephrine, dopamine, dihydroxyphenylalanine, dihydroxyphenylglycol, and dihydroxyphenylacetic acid] after supine rest on a control (C) day and after 4 h and 7 and 14 days of HDBR. Urine was collected after 2 h of supine rest during day C, 2 h before HDBR, and during the intervals 1-4, 4-24, 144-168 (day 7), and 312-336 h (day 14) of HDBR. All subjects had decreased plasma and blood volumes (mean 16%), atriopeptin levels (31%), and peripheral venous pressure (26%) after HDBR. NE excretion on day 14 of HDBR was decreased by 35% from that on day C, without further trends as HDBR continued, whereas plasma levels were only variably and nonsignificantly decreased. Excretion rates of dihydroxyphenylglycol and dihydroxyphenylalanine decreased slightly during HDBR; excretion rates of epinephrine, dopamine, and dihydroxyphenylacetic acid and plasma levels of catechols were unchanged. The results suggest that HDBR produces sustained inhibition of sympathoneural release, turnover, and synthesis of NE without affecting adrenomedullary secretion or renal dopamine production. Concurrent hypovolemia probably interferes with detection of sympathoinhibition by plasma levels of NE and other catechols in this setting. Sympathoinhibition, despite decreased blood volume, may help to explain orthostatic intolerance in astronauts returning from spaceflights.

  16. Mechanisms of prolonged lithium therapy-induced nephrogenic diabetes insipidus.

    PubMed

    Behl, Tapan; Kotwani, Anita; Kaur, Ishneet; Goel, Heena

    2015-05-15

    Nephrogenic diabetes insipidus is a clinical sub-type of a diversely expounded disorder, named diabetes insipidus. It is characterized by inability of the renal cells to sense and respond to the stimulus of vasopressin. Amongst its various etiologies, one of the most inevitable causes includes lithium-induced instigation. Numerous studies reported marked histological damage to the kidneys upon long-term treatment with lithium. The recent researches have hypothesized many lithium-mediated mechanisms to explain the damage and dysfunction caused in the kidneys following lithium exposure. These mechanisms, widely, intend to justify the lithium-induced electrolyte imbalance, its interference with some vital proteins and a specific steroidal hormone, obstruction caused to a certain imperative transducer pathway and the renal tubular acidification defect produced on its prolonged therapy. Thorough study of such mechanisms aids in better understanding of the role of lithium in the pathophysiology of this disorder. Hence, the ameliorated knowledge regarding disease-pathology might prove beneficial in developing therapies that aim on disrupting the various lithium-mediated pathways. Hence, this may effectively lead to the demonstration of a novel treatment for nephrogenic diabetes insipidus, which is, at present, limited to the use of diuretics which block lithium reuptake into the body.

  17. Prolonged Adaptive Evolution of a Defensive Gene in the Solanaceae.

    PubMed

    Rausher, Mark D; Huang, Jie

    2016-01-01

    Although plants and their natural enemies may coevolve for prolonged periods, little is known about how long individual plant defensive genes are involved in the coevolutionary process. We address this issue by examining patterns of selection on the defensive gene threonine deaminase (TD). Tomato (Solanum lycopersicum) has two copies of this gene. One performs the canonical housekeeping function in amino acid metabolism of catalyzing the first reaction in the conversion of threonine to isoleucine. The second copy functions as an antinutritive defense against lepidopteran herbivores by depleting threonine in the insect gut. Wild tobacco (Nicotiana attenuata) also contains a defensive copy. We show that a single copy of TD underwent two or three duplications near the base of the Solanaceae. One copy retains the housekeeping function, whereas a second copy evolved defensive functions. Positive selection occurred on the branch of the TD2 gene tree subtending the common ancestor of the Nicotianoideae and Solanoideae. It also occurred within the Solanoideae clade but not within the Nicotianoideae clade. Finally, it occurred on most branches leading from the common ancestor to S. lycopersicum. Based on recent calibrations of the Solanaceae phylogeny, TD2 experienced adaptive substitutions for a period of 30-50 My. We suggest that the most likely explanation for this result is fluctuating herbivore abundances: When herbivores are rare, relaxed selection increases the likelihood that slightly disadvantageous mutations will be fixed by drift; when herbivores are common, increased selection causes the evolution of compensatory adaptive mutations. Alternative explanations are also discussed.

  18. Quality assessment of palm products upon prolonged heat treatment.

    PubMed

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai

    2008-01-01

    Extending the frying-life of oils is of commercial and economic importance. Due to this fact, assessment on the thermal stability of frying oils could provide considerable savings to the food processors. In this study, the physico-chemical properties of five palm products mainly palm oil, single-fractionated palm olein, double-fractionated palm olein, red palm olein and palm-based shortening during 80 hours of heating at 180 degrees C were investigated. Heating properties of these products were then compared with that of high oleic sunflower oil, which was used as reference oil. The indices applied in evaluating the quality changes of oils were free fatty acid, smoke point, p-anisidine value, tocols, polar and polymer compounds. Three palm products i.e. palm oil, single-fractionated palm olein and double-fractionated palm olein were identified to be the most stable in terms of lower formation of free fatty acid, polar and polymer compounds as well as preserving higher smoke point and tocols content compared to the other three oils. The low intensity of hydrolytic and oxidative changes due to prolonged heating, suggests that these palm products are inherently suitable for frying purposes.

  19. Characterization of renal response to prolonged immersion in normal man

    NASA Technical Reports Server (NTRS)

    Epstein, M.; Denunzio, A. G.; Ramachandran, M.

    1980-01-01

    ?jDuring the initial phase of space flight, there is a translocation of fluid from the lower parts of the body to the central vascular compartment with a resultant natriuresis, diuresis, and weight loss. Because water immersion is regarded as an appropriate model for studying the redistribution of fluid that occurs in weightlessness, an immersion study of relatively prolonged duration was carried out in order to characterize the temporal profile of the renal adaptation to central hypervolemia. Twelve normal male subjects underwent an immersion study of 8-h duration in the sodium-replete state. Immersion resulted in marked natriuresis and diuresis which were sustained throughout the immersion period. The failure of that natriuresis and diuresis of immersion to abate or cease despite marked extracellular fluid volume contraction as evidenced by a mean weight loss of -2.2 + or - 0.3 kg suggests that central blood volume was not restored to normal and that some degree of central hypervolemia probably persisted.

  20. Massive and prolonged deep carbon emissions associated with continental rifting

    NASA Astrophysics Data System (ADS)

    Lee, Hyunwoo; Muirhead, James D.; Fischer, Tobias P.; Ebinger, Cynthia J.; Kattenhorn, Simon A.; Sharp, Zachary D.; Kianji, Gladys

    2016-02-01

    Carbon from Earth’s interior is thought to be released to the atmosphere mostly via degassing of CO2 from active volcanoes. CO2 can also escape along faults away from active volcanic centres, but such tectonic degassing is poorly constrained. Here we use measurements of diffuse soil CO2, combined with carbon isotopic analyses to quantify the flux of CO2 through fault systems away from active volcanoes in the East African Rift system. We find that about 4 Mt yr-1 of mantle-derived CO2 is released in the Magadi-Natron Basin, at the border between Kenya and Tanzania. Seismicity at depths of 15-30 km implies that extensional faults in this region may penetrate the lower crust. We therefore suggest that CO2 is transferred from upper-mantle or lower-crustal magma bodies along these deep faults. Extrapolation of our measurements to the entire Eastern rift of the rift system implies a CO2 flux on the order of tens of megatonnes per year, comparable to emissions from the entire mid-ocean ridge system of 53-97 Mt yr-1. We conclude that widespread continental rifting and super-continent breakup could produce massive, long-term CO2 emissions and contribute to prolonged greenhouse conditions like those of the Cretaceous.

  1. Rare bacterium of new genus isolated with prolonged enrichment culture.

    PubMed

    Hashizume, Akiko; Fudou, Ryosuke; Jojima, Yasuko; Nakai, Ryohsuke; Hiraishi, Akira; Tabuchi, Akira; Sen, Kikuo; Shibai, Hiroshiro

    2004-01-01

    Dynamic change in microbial flora was monitored with an oxygen electrode. The 1st phase microorganisms, which first grew well in LB medium, were followed by the 2nd phase microorganisms, which supposedly assimilated microbial cells of the 1st phase and their metabolites. In a similar way, a change in microbial flora was observed from the 1st phase to the 4th phase in 84 hr. Based on this observation, prolonged enrichment culture was done for as long as two months to increase the ratio of existence of rare microorganisms. From these culture liquids, four slow-growing bacteria (provisionally named Shinshu-ah1, -ah2, -ah3, and -ah4), which formed scarcely visible small colonies, were isolated. Sequence analysis of their 16S rDNA showed that Shinshu-ah1 had 97% homology with Bradyrhizobium japonicum and uncultured alpha proteobacterium clone blaii 16, Shinshu-ah2 91% with Rasbo bacterium, Alpha proteobacterium 34619, Bradyrhizobium genosp. P, Afipia felis and an unidentified bacterium, Shinshu-ah3 99% with Methylobacterium mesophilicum, and Shinshu-ah4 95% with Agromyces ramosus DSM 43045. Phylogenetic study indicated that Shinshu-ah2 had a possibility to form a new family, Shinshu-ah1 a new genus, and Shinshu-ah4 a new species.

  2. Radiation burdens for humans on prolonged exomagnetospheric voyages.

    PubMed

    Moore, F D

    1992-03-01

    The severity of radiation exposure for astronauts outside the magnetosphere poses a critical unanswered question bearing on the use of manned vehicles in extended exploration of the solar system (moon, Mars). Such prolonged exomagnetospheric voyages (1-3 years) enter a radiologic environment more severe than that of low earth orbit, an annual dose equivalent in the range of 0.3-0.5 Sv (30-50 rem), and a lifetime excess cancer fatality risk of 3-5% due to low linear-energy-transfer components of galactic cosmic radiation alone. To this calculus must be added estimates for high-atomic-number, high-energy particles, the probability of solar particle events, and the limited effectiveness of shielding. For a 3-year Mars voyage these could elevate the dose equivalent to 1.5-2.25 Sv (150-225 rem) total (0.5-0.75 Sv [50-75 rem] annual) and risks to 5-9% excess cancer fatality. Both the mission (civilian scientific research) and the alternatives (unmanned robotic devices) enter the policy decision here. This paper presents a brief review of pertinent physical and biological data and of research urgently needed before reaching a decision on this question.

  3. Depth perception after prolonged usage of night vision goggles.

    PubMed

    Sheehy, J B; Wilkinson, M

    1989-06-01

    The present study was initiated following a report that a few helicopter pilots had failed a test of stereoscopic depth perception after a prolonged training flight employing night vision goggles (NVGs). In order to determine the cause of the loss, 12 helicopter pilots/copilots were assessed for depth perception, lateral and vertical phoria, and contrast sensitivity before and after training flights requiring the pilots to wear night vision goggles for the duration of the flight. Pilots flew one to three missions while wearing either PVS-5A or AN/AVS-6 goggles. Mission duration ranged from 1 to 4 h. The results indicate that contrast sensitivity and depth perception when monocular cues are present did not degrade over the course of the mission. Lateral phoria, however, did demonstrate an average exophoric shift of 1.5 prism diopters for 12 out of the 24 missions. The results indicate that the original report of a loss of depth perception based on a test of depth requiring stereopsis might have been caused by a shift in lateral phoria. It would be expected that as additional fusional effort is required, the minimum resolvable disparity degrades due to the increase in accommodation brought about through vergence accommodation. Possible causes for the phoria shift and future testing are discussed.

  4. Effect of prolonged space flight on cardiac function and dimensions

    NASA Technical Reports Server (NTRS)

    Henry, W. L.; Epstein, S. E.; Griffith, J. M.; Goldstein, R. E.; Redwood, D. R.

    1974-01-01

    Echocardiographic studies were performed preflight 5 days before launch and on recovery day and 1, 2, 4, 11, 31 and 68 days postflight. From these echocardiograms measurements were made. From these primary measurements, left ventricular end-diastolic volume, end-systolic volume, stroke volume, and mass were derived using the accepted assumptions. Findings in the Scientist Pilot and Pilot resemble those seen in trained distance runners. Wall thickness measurements were normal in all three crewmembers preflight. Postflight basal studies were unchanged in the Commander on recovery day through 68 days postflight in both the Scientist Pilot and Pilot, however, the left ventricular end-diastolic volume, stroke volume, and mass were decreased slightly. Left ventricular function curves were constructed for the Commander and Pilot by plotting stroke volume versus end-diastolic volume. In both astronauts, preflight and postflight data fell on the same straight line demonstrating that no deterioration in cardiac function had occurred. These data indicate that the cardiovascular system adapts well to prolonged weightlessness and suggest that alterations in cardiac dimensions and function are unlikely to limit man's future in space.

  5. Association between Muscle Synergy and Stability during Prolonged Walking

    PubMed Central

    Suzuki, Keisuke; Nishida, Yusuke; Mitsutomi, Kazuhiko

    2014-01-01

    [Purpose] The purpose of this study was to examine whether changes in muscle synergy could affect gait stability or muscle activity by comparing muscle activity before and after prolonged walking. [Subjects and Methods] Twelve healthy male subjects walked on a treadmill for 10 min as a warm-up. Data were recorded from the participants during the first and last 1 min during 90 min of walking at 4.5 km/h. Electromyographic (EMG) activity was recorded for 7 leg muscles, and patterns of coordination were determined by principal component analysis (PCA). The patterns of activity within the anatomic muscle groups were additionally determined by repeating PCA. iEMG was calculated using the mean EMG for each cycle step during the 1 min walking periods. The largest Lyapunov exponent was calculated to quantify each subject’s inherent local dynamic stability. [Results] The patterns for each of the 7 muscles showed no change between the start and end periods. However, the end period showed a higher co-activation of the triceps surae, lower iEMG of the medial gastrocnemius, and a smaller largest Lyapunov exponent of the mediolateral and anteroposterior directions than those observed during the start period. [Conclusion] The increase in triceps surae co-activation may be associated with gait stability. PMID:25364133

  6. Mueller-Lyer decrement: practice or prolonged inspection?

    NASA Technical Reports Server (NTRS)

    Schiano, D. J.; Jordan, K.

    1990-01-01

    Noting the similarity between the illusion decrement and selective adaptation paradigms, Long has challenged the view that illusion decrement effects reflect a strategic--as opposed to a structural--underlying mechanism, and has called for further research on this issue. To investigate the confound between prolonged free inspection and repeated trials in the standard decrement procedure, the effects of three inspection conditions (continuous, intermittent, and immediate) on the magnitude of the overestimation Mueller-Lyer illusion have been assessed under two levels of trials (a total of two or six judgments). Significant illusion decline was found only under conditions of repeated trials, with either continuous or intermittent inspection. These findings do not support the predictions of purely structural theories (including neural adaptation and efferent readiness theories), according to which degree of decrement should be determined solely by viewing time. Instead, the data demonstrate that illusion decrement is a product of practice, providing converging evidence for the view of decrement as involving a cognitive 'recalibration' or learning process.

  7. [Prolonged blockade of nervus ischiadicus in a system of complex treatment of patients, suffering complicated diabetic foot syndrome].

    PubMed

    Shapoval, S D; Savon, I L; Sofilkanych, M M

    2015-03-01

    General principles of treatment in patients, suffering diabetic foot syndrome, are adduced. There was proved, that reconvalescence of the patients depends not only on quality of complex treatment, but from optimal choice of anesthesia method, its impact on postoperative period course. Application of prolonged blockade of n. ischiadicus gives possibility to perform operative intervention on the lower extremity in full volume, guarantees sufficient motor and sensory block, permits patients to reject from application of narcotic analgetics, to reduce the dose of strong nonnarcotic analgetics, the terms of transition of the wound process phase I into phase II, promotes early activization of patients postoperatively, constitutes alternative for other methods of anesthesiological support.

  8. Decrease in eccentric quadriceps and hamstring strength in recreational alpine skiers after prolonged skiing

    PubMed Central

    Koller, Arnold; Fuchs, Birgit; Leichtfried, Veronika; Schobersberger, Wolfgang

    2015-01-01

    Background To effectively prevent injury in recreational alpine skiing, it is important to identify modifiable risk factors that can be targeted through exercise and training. Fatigue is a potential risk factor in recreational skiing, but no investigations have evaluated concentric/eccentric quadriceps and hamstring fatigue in recreational skiers. We tested the hypothesis that recreational skiing is associated with more pronounced eccentric as compared with concentric muscle fatigue. Methods Twenty-four healthy and fit recreational skiers (14 male and 10 female) performed an isokinetic muscle test 1 day before, 1 h after, and 24 h after a 4 h skiing session. The testing protocol consisted of concentric and eccentric quadriceps and hamstring contractions for both legs. Results Eccentric peak hamstring torque (both thighs) and eccentric peak quadriceps torque (left thigh) were reduced in male and female participants (p<0.05). Reduced peak torques were still present 24 h after the skiing session. There were no other significant findings. Summary Recreational skiing is associated with prolonged (at least 24 h) eccentric quadriceps (left thigh) and hamstring (both thighs) fatigue in men and women. Eccentric quadriceps and hamstring fatigue may be a potential injury risk factor in male and female recreational skiers. This provides some justification for judicious use of additional eccentric training modalities for alpine skiing. PMID:27900115

  9. Disruption of the Termite Gut Microbiota and Its Prolonged Consequences for Fitness ▿ †

    PubMed Central

    Rosengaus, Rebeca B.; Zecher, Courtney N.; Schultheis, Kelley F.; Brucker, Robert M.; Bordenstein, Seth R.

    2011-01-01

    The disruption of host-symbiont interactions through the use of antibiotics can help elucidate microbial functions that go beyond short-term nutritional value. Termite gut symbionts have been studied extensively, but little is known about their impact on the termite's reproductive output. Here we describe the effect that the antibiotic rifampin has not only on the gut microbial diversity but also on the longevity, fecundity, and weight of two termite species, Zootermopsis angusticollis and Reticulitermes flavipes. We report three key findings: (i) the antibiotic rifampin, when fed to primary reproductives during the incipient stages of colony foundation, causes a permanent reduction in the diversity of gut bacteria and a transitory effect on the density of the protozoan community; (ii) rifampin treatment reduces oviposition rates of queens, translating into delayed colony growth and ultimately reduced colony fitness; and (iii) the initial dosages of rifampin had severe long-term fitness effects on Z. angusticollis. Taken together, our findings demonstrate that the antibiotic-induced perturbation of the microbial community is associated with prolonged reductions in longevity and fecundity. A causal relationship between these changes in the gut microbial population structures and fitness is suggested by the acquisition of opportunistic pathogens and incompetence of the termites to restore a pretreatment, native microbiota. Our results indicate that antibiotic treatment significantly alters the termite's microbiota, reproduction, colony establishment, and ultimately colony growth and development. We discuss the implications for antimicrobials as a new application to the control of termite pest species. PMID:21571887

  10. Disruption of the termite gut microbiota and its prolonged consequences for fitness.

    PubMed

    Rosengaus, Rebeca B; Zecher, Courtney N; Schultheis, Kelley F; Brucker, Robert M; Bordenstein, Seth R

    2011-07-01

    The disruption of host-symbiont interactions through the use of antibiotics can help elucidate microbial functions that go beyond short-term nutritional value. Termite gut symbionts have been studied extensively, but little is known about their impact on the termite's reproductive output. Here we describe the effect that the antibiotic rifampin has not only on the gut microbial diversity but also on the longevity, fecundity, and weight of two termite species, Zootermopsis angusticollis and Reticulitermes flavipes. We report three key findings: (i) the antibiotic rifampin, when fed to primary reproductives during the incipient stages of colony foundation, causes a permanent reduction in the diversity of gut bacteria and a transitory effect on the density of the protozoan community; (ii) rifampin treatment reduces oviposition rates of queens, translating into delayed colony growth and ultimately reduced colony fitness; and (iii) the initial dosages of rifampin had severe long-term fitness effects on Z. angusticollis. Taken together, our findings demonstrate that the antibiotic-induced perturbation of the microbial community is associated with prolonged reductions in longevity and fecundity. A causal relationship between these changes in the gut microbial population structures and fitness is suggested by the acquisition of opportunistic pathogens and incompetence of the termites to restore a pretreatment, native microbiota. Our results indicate that antibiotic treatment significantly alters the termite's microbiota, reproduction, colony establishment, and ultimately colony growth and development. We discuss the implications for antimicrobials as a new application to the control of termite pest species.

  11. Achilles tendon mechanical properties after both prolonged continuous running and prolonged intermittent shuttle running in cricket batting.

    PubMed

    Houghton, Laurence; Dawson, Brian; Rubenson, Jonas

    2013-08-01

    Effects of prolonged running on Achilles tendon properties were assessed after a 60 min treadmill run and 140 min intermittent shuttle running (simulated cricket batting innings). Before and after exercise, 11 participants performed ramp-up plantar flexions to maximum-voluntary-contraction before gradual relaxation. Muscle-tendon-junction displacement was measured with ultrasonography. Tendon force was estimated using dynamometry and a musculoskeletal model. Gradients of the ramp-up force-displacement curves fitted between 0-40% and 50-90% of the preexercise maximal force determined stiffness in the low- and high-force-range, respectively. Hysteresis was determined using the ramp-up and relaxation force-displacement curves and elastic energy storage from the area under the ramp-up curve. In simulated batting, correlations between tendon properties and shuttle times were also assessed. After both protocols, Achilles tendon force decreased (4% to 5%, P < .050), but there were no changes in stiffness, hysteresis, or elastic energy. In simulated batting, Achilles tendon force and stiffness were both correlated to mean turn and mean sprint times (r = -0.719 to -0.830, P < .050). Neither protocol resulted in fatigue-related changes in tendon properties, but higher tendon stiffness and plantar flexion force were related to faster turn and sprint times, possibly by improving force transmission and control of movement when decelerating and accelerating.

  12. Risperidone-induced action potential prolongation is attenuated by increased repolarization reserve due to concomitant block of I(Ca,L).

    PubMed

    Christ, Torsten; Wettwer, Erich; Ravens, Ursula

    2005-05-01

    The neuroleptic risperidone is an effective blocker of the rapidly activating component of the delayed rectifier current (I(Kr)) and hence is expected to prolong cardiac action potential duration (APD). However, unlike with other typical I(Kr) blockers we failed to demonstrate a marked prolongation of late repolarization with risperidone. It is hypothesized that the APD-prolonging effect of risperidone is masked by the high repolarization reserve due to the prominent delayed rectifier currents I(Kr) and I(Ks) in guinea pig papillary muscle. Action potentials and force of contraction were recorded in isolated guinea pig papillary muscles. L-type calcium current I(Ca,L) and I(Kr) were measured using the standard patch clamp technique in single ventricular cardiomyocytes. Reduction of the repolarization reserve by the blocking of I(Ks) with chromanol 239B augmented the effect of the selective I(Kr) blocker E-4031, but not of risperidone, although both drugs completely blocked I(Kr). In contrast to E-4031 risperidone markedly reduced the force of contraction due to the partial blocking of I(Ca,L) in the same concentration range as required for block of I(Kr). Reduction of the repolarization reserve by the blocking of I(Ks) cannot exacerbate the APD-prolonging effect of risperidone. However, even incomplete concomitant blocking of I(Ca,L) attenuates the APD-prolonging effect of the complete blocking of I(Kr). This behaviour may explain the small APD-prolonging effect of risperidone despite the drug's robust blocking of I(Kr).

  13. Intrasplenic transplantation of allogeneic hepatocytes prolongs survival in anhepatic rats.

    PubMed

    Arkadopoulos, N; Lilja, H; Suh, K S; Demetriou, A A; Rozga, J

    1998-11-01

    To examine whether hepatocytes transplanted in the spleen can function as an ectopic liver, we performed hepatocyte transplantation in rats that were rendered anhepatic. Total hepatectomy was performed by using a novel single-stage technique. Following hepatectomy, Group 1 rats (n = 16) were monitored until death to determine survival time without prior intervention. Group 2 anhepatic rats (n = 20) were sacrificed at various times to measure blood hepatocyte growth factor (HGF) and transforming growth factor beta1 (TGF-beta1) levels. Group 3 (n = 16) rats received intrasplenic injection of isolated hepatocytes (2.5 x 10(7) cells/rat) followed by total hepatectomy after 3 days. Group 4 (n = 12) sham-transplanted rats received intrasplenic saline infusion, and after 3 days they were rendered anhepatic. Group 2, 3, and 4 rats were maintained on daily Cyclosporine A (10 mg/kg; intramuscularly). Group 1 anhepatic rats survived for 22.4 +/- 5.2 hours (standard deviation). The anhepatic state was associated with a progressive and statistically significant rise in blood HGF and TGF-beta1 levels. Rats that received hepatocyte transplantation before total hepatectomy had a significantly longer survival time than sham-transplanted anhepatic controls (34.1 +/- 8.5 vs. 15.5 +/- 4.8 hrs, P < .01). Additionally, at 12 hours post-hepatectomy, transplanted rats had significantly lower blood ammonia, prothrombin time, international normalized ratio, and TGF-beta1 levels when compared with sham-transplanted controls. In conclusion, intrasplenic transplantation of allogeneic hepatocytes prolonged survival, improved blood chemistry, and lowered blood TGF-beta1 levels in rats rendered anhepatic.

  14. Predictors of Prolonged Hospitalization in Patients with Fever

    PubMed Central

    2016-01-01

    Objective: The study was conducted to analyze the predictors of prolonged hospitalization in patients with fever. Patients and Methods: This was a prospective cohort study conducted from July - December 2015 at Ayub Teaching Hospital, Pakistan. Convenience sampling was used to enroll the patients who visited the hospital during the study duration. A sample size of 115 patients was calculated. It included patients who presented with a new onset fever which started in the last month, and the cause of fever was undiagnosed at the time of admission. Critical patients were excluded. Data for more than 30 variables was collected on a pro forma. Univariate regression methods were used to analyze the data in the Statistical Package for Social Sciences (SPSS), version 23. Results: A total of 115 patients were analyzed. Males constituted 66/115 (57.4%). The mean age for patients was 43.6 years (standard deviation (SD) = 20.2). On admission, low platelet counts (p = 0.001), high erythrocyte sedimentation rate (ESR) counts (p = 0.007), a high total leukocyte count (TLC) (p = 0.029), and involvement of nervous (p = 0.021), cardiovascular (p = 0.04), respiratory (p = 0.043), gastroenterological (p = 0.042), hematological (p = 0.028), or urogenital system (p = 0.016) were associated with a longer stay in the hospital. Conclusion: Patients with an undiagnosed and new onset fever will have a longer hospital stay if, on admission, they have low platelet counts, a higher ESR, a high TLC, or involvement of nervous, cardiovascular, respiratory, gastrointestinal, hematological, or urogenital systems. An early identification of risk factors can lead to better treatment and may also lead to a decreased hospital stay. PMID:27774357

  15. Altered locus coeruleus-norepinephrine function following single prolonged stress.

    PubMed

    George, Sophie A; Knox, Dayan; Curtis, Andre L; Aldridge, J Wayne; Valentino, Rita J; Liberzon, Israel

    2013-03-01

    Data from preclinical and clinical studies have implicated the norepinephrine system in the development and maintenance of post-traumatic stress disorder. The primary source of norepinephrine in the forebrain is the locus coeruleus (LC); however, LC activity cannot be directly measured in humans, and previous research has often relied upon peripheral measures of norepinephrine to infer changes in central LC-norepinephrine function. To directly assess LC-norepinephrine function, we measured single-unit activity of LC neurons in a validated rat model of post-traumatic stress disorder - single prolonged stress (SPS). We also examined tyrosine hydroxylase mRNA levels in the LC of SPS and control rats as an index of norepinephrine utilisation. For electrophysiological recordings, 92 LC neurons were identified from 19 rats (SPS, 12; control, 7), and spontaneous and evoked responses to a noxious event (paw compression) were recorded. Baseline and restraint stress-evoked tyrosine hydroxylase mRNA expression levels were measured in SPS and control rats (n = 16 per group) in a separate experiment. SPS rats showed lower spontaneous activity but higher evoked responses, leading to an enhanced signal-to-noise ratio of LC neurons, accompanied by impaired recovery from post-stimulus inhibition. In concert, tyrosine hydroxylase mRNA expression in the LC of SPS rats tended to be lower at baseline, but was exaggerated following restraint stress. These data demonstrate persistent changes in LC function following stress/trauma in a rat model of post-traumatic stress, as measured by differences in both the electrophysiological properties of LC neurons and tyrosine hydroxylase mRNA transcription.

  16. Triathlete characterization and response to prolonged strenuous competition.

    PubMed

    Holly, R G; Barnard, R J; Rosenthal, M; Applegate, E; Pritikin, N

    1986-02-01

    The purpose of this study was to characterize triathletes and to assess their responses to prolonged, strenuous competition. Nine triathletes (6 males, 3 females) participated. Mean V0(2)max and percentage of body fat were 72.0 ml X kg-1 X min-1 and 7.1%, respectively, in the four males who finished in the top 15. This compared to values of 58.4 ml X kg-1 X min-1/10.2% and 58.7 ml X kg-1 X min-1/12.6% in the other males and females, respectively. In the 5 wk preceding competition (Hawaii "Ironman Triathlon World Championship") the average daily training of the four top 15 male competitors consisted of swimming 2720 m, running 13.6 km, and biking 84.0 km. This was approximately 1.5 times greater than that of the other athletes. The average training diet was 59% carbohydrate, 21% fat, and 20% protein. Immediately following competition, SGOT, SGPT, and serum LDH were increased 700, 262, and 222% (P less than 0.004), respectively, and still remained marginally elevated 5-6 d later (P less than 0.02). Immediately following competition, serum triglycerides remained unchanged, while serum glucose, glycerol, and nonesterified fatty acids increased 52, 248, and 191% (P less than 0.005), respectively. By 5-6 d post-competition glucose had returned to normal, while triglycerides were elevated 94% (P less than 0.005) and nonsterified fatty acids were decreased 58% (P less than 0.01).

  17. Central and regional hemodynamics in prolonged space flights

    NASA Astrophysics Data System (ADS)

    Gazenko, O. G.; Shulzhenko, E. B.; Turchaninova, V. F.; Egorov, A. D.

    This paper presents the results of measuring central and regional (head, forearm, calf) hemodynamics at rest and during provocative tests by the method of tetrapolar rheography in the course of Salyut-6-Soyuz and Salyut-7-Soyuz missions. The measurements were carried out during short-term (19 man-flights of 7 days in duration) and long-term (21 man-flights of 65-237 days in duration) manned missions. At rest, stroke volume (SV) and cardiac output (CO) as well as heart rate (HR) decreased insignificantly (in short-term flights) or remained essentially unchanged (in long-term flights). In prolonged flights CO increased significantly in response to exercise tests due to an increase in HR and the lack of changes in SV. After exercise tests SV and CO decreased as compared to the preflight level. During lower body negative pressure (LBNP) tests HR and CO were slightly higher than preflight. Changes in regional hemodynamics included a distinct decrease of pulse blood filling (PBF) of the calf, a reduction of the tone of large vessels of the calf and small vessels of the forearm. Head examination (in the region of the internal carotid artery) showed a decrease of PBF of the left hemisphere (during flight months 2-8) and a distinct decline of the tone of small vessels, mainly, in the right hemisphere. During LBNP tests the tone of pre- and postcapillary vessels of the brain returned to normal while PBF of the right and left hemisphere vessels declined. It has been shown that regional circulation variations depend on the area examined and are induced by a rearrangement of total hemodynamics of the human body in microgravity. This paper reviews the data concerning changes in central and regional circulation of men in space flights of different duration.

  18. Prolonged administration of antithymocyte serum in mice. II. Histopathological investigation

    PubMed Central

    Simpson, Elizabeth; Nehlsen, Sandra L.

    1971-01-01

    Prolonged administration of ATS to mice resulted in depletion of small lymphocytes in the thymus-dependent (paracortical) areas of lymph nodes in all mice. Small lymphocyte depletion of the thymus-dependent periarteriolar region of the spleen was present in most mice, although this feature was masked by plasmacytosis in this region in some. Depletion of small lymphocytes in the thymus-dependent areas of Peyer's patches was evident in some of the younger mice. None of these changes in lymphoid organs were seen in control mice, untreated or given NRS. The thymus was unaffected except in some ATS- or NRS-treated mice which were sick and/or old, in which the narrowing of the thymic cortex was attributed to non-specific stress. Plasmacytosis was seen in the medullae of lymph nodes of both ATS- and NRS-treated mice, although it was more intense in the latter. In non-lymphoid organs the most striking changes were seen in the kidneys of mice treated both with ATS and NRS. Complex-type nephritis followed by amyloidosis was seen in a large proportion of mice over 6 months old in both these groups and in these mice amyloid was seen frequently in other organs, including spleen and liver. Tumours occurred in fifty-four ATS-treated mice, but in no other group. Fifty-two of these tumours were attributable to polyoma virus; two other were lymphoblastomas. Reticulum cell hyperplasia was seen in two further mice. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 13Fig. 14Fig. 15Fig. 16Fig. 17Fig. 18 PMID:4326920

  19. Does prolonged biliary obstructive jaundice sensitize the liver to endotoxemia?

    PubMed

    Iida, Ayako; Yoshidome, Hiroyuki; Shida, Takashi; Kimura, Fumio; Shimizu, Hiroaki; Ohtsuka, Masayuki; Morita, Yasuhiro; Takeuchi, Dan; Miyazaki, Masaru

    2009-04-01

    Biliary obstructive jaundice (OJ) is an important clinical consideration concerning high bacteremic risk. Hepatocyte apoptosis is one of the causes of cholestatic liver injury. The aim of the current study was to examine the precise pathway and time course of hepatocyte apoptosis during OJ with LPS administration and to determine if OJ sensitizes the liver to endotoxemia. Male C57BL/6 mice were subjected to bile duct ligation and division and were administered with LPS at 3 (OJ3) or 14 (OJ14) days after surgery. Fas ligand expression, poly (adenosine diphosphate-ribose) polymerase p85 fragment immunohistochemistry, activation of caspases 3, 8, and 9, serum alanine aminotransferase levels, and hepatic adenosine triphosphate (ATP) contents were examined. Survival after LPS administration in male C57BL/6 or gld/gld (Fas ligand-deficient) mice was determined. The expression of Fas ligand increased during OJ. After LPS administration, the expression of cleaved caspases 3 and 8 increased in Sham3, Sham14, OJ3, and OJ14 mice, and it significantly increased in OJ14 compared with other mice. Poly (adenosine diphosphate-ribose) polymerase p85 immunohistochemistry showed significant hepatocyte apoptosis after LPS administration in OJ14 mice relative to OJ3. In OJ14 with LPS administration, ATP contents significantly decreased and alanine aminotransferase levels increased. Hepatocyte apoptosis was decreased in gld/gld OJ14 mice compared with C57BL/6 OJ14. All C57BL/6 OJ14 mice with LPS died, but survival in gld/gld OJ14 significantly ameliorated. In prolonged OJ with LPS administration, hepatocyte apoptosis depending on Fas ligand expression significantly increased in association with a decrease in ATP contents, thus resulting in liver necrapoptosis.

  20. Heterotrophic compensation: a possible mechanism for resilience of coral reefs to global warming or a sign of prolonged stress?

    PubMed

    Hughes, Adam D; Grottoli, Andréa G

    2013-01-01

    Thermally induced bleaching has caused a global decline in corals and the frequency of such bleaching events will increase. Thermal bleaching severely disrupts the trophic behaviour of the coral holobiont, reducing the photosynthetically derived energy available to the coral host. In the short term this reduction in energy transfer from endosymbiotic algae results in an energy deficit for the coral host. If the bleaching event is short-lived then the coral may survive this energy deficit by depleting its lipid reserves, or by increasing heterotrophic energy acquisition. We show for the first time that the coral animal is capable of increasing the amount of heterotrophic carbon incorporated into its tissues for almost a year following bleaching. This prolonged heterotrophic compensation could be a sign of resilience or prolonged stress. If the heterotrophic compensation is in fact an acclimatization response, then this physiological response could act as a buffer from future bleaching by providing sufficient heterotrophic energy to compensate for photoautotrophic energy losses during bleaching, and potentially minimizing the effect of subsequent elevated temperature stresses. However, if the elevated incorporation of zooplankton is a sign that the effects of bleaching continue to be stressful on the holobiont, even after 11 months of recovery, then this physiological response would indicate that complete coral recovery requires more than 11 months to achieve. If coral bleaching becomes an annual global phenomenon by mid-century, then present temporal refugia will not be sufficient to allow coral colonies to recover between bleaching events and coral reefs will become increasingly less resilient to future climate change. If, however, increasing their sequestration of zooplankton-derived nutrition into their tissues over prolonged periods of time is a compensating mechanism, the impacts of annual bleaching may be reduced. Thus, some coral species may be better

  1. Corticosteroid Treatment for Prolonged Fever in Hepatosplenic Cat-Scratch Disease.

    PubMed

    Phan, Amanda; Castagnini, Luis A

    2016-12-01

    Hepatosplenic cat-scratch disease (CSD) may cause prolonged fever. We present the case of a 4-year-old boy with confirmed hepatosplenic CSD with fever lasting 3 months despite use of multiple different antimicrobial agents. The patient became afebrile soon after corticosteroid therapy was started. Our case indicates corticosteroids may be useful in patients with hepatosplenic CSD and prolonged fever.

  2. Prolonged treatment for acute symptomatic refractory status epilepticus: outcome in children.

    PubMed

    Sahin, Mustafa; Menache, Caroline C; Holmes, Gregory L; Riviello, James J

    2003-08-12

    High-dose suppressive therapy (HDST) is used to treat refractory status epilepticus (RSE). Prolonged therapy is required in some cases, and prognosis is important in making therapeutic decisions. The authors therefore studied the long-term outcome in previously normal children who survived prolonged HDST for acute symptomatic RSE. All have intractable epilepsy, and none returned to baseline.

  3. Imagining the Alternatives to Life Prolonging Treatments: Elders' Beliefs about the Dying Experience

    ERIC Educational Resources Information Center

    Winter, Laraine; Parker, Barbara; Schneider, Melissa

    2007-01-01

    Deciding for or against a life-prolonging treatment represents a choice between prolonged life and death. When the death alternative is not described, individuals must supply their own assumptions. How do people imagine the experience of dying? The authors asked 40 elderly people open-ended questions about dying without 4 common life-prolonging…

  4. Effect of the Prolonged Inspiratory to Expiratory Ratio on Oxygenation and Respiratory Mechanics During Surgical Procedures.

    PubMed

    Park, Jin Ha; Lee, Jong Seok; Lee, Jae Hoon; Shin, Seokyung; Min, Nar Hyun; Kim, Min-Soo

    2016-03-01

    Prolonged inspiratory to expiratory (I:E) ratio ventilation has been researched to reduce lung injury and improve oxygenation in surgical patients with one-lung ventilation (OLV) or carbon dioxide (CO2) pneumoperitoneum. We aimed to confirm the efficacy of the 1:1 equal ratio ventilation (ERV) compared with the 1:2 conventional ratio ventilation (CRV) during surgical procedures. Electronic databases, including PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Google Scholar were searched.Prospective interventional trials that assessed the effects of prolonged I:E ratio of 1:1 during surgical procedures. Adult patients undergoing OLV or CO2 pneumoperitoneum as specific interventions depending on surgical procedures. The included studies were examined with the Cochrane Collaboration's tool. The data regarding intraoperative oxygenation and respiratory mechanics were extracted, and then pooled with standardized mean difference (SMD) using the method of Hedges. Seven trials (498 total patients, 274 with ERV) were included. From overall analysis, ERV did not improve oxygenation at 20 or 30 minutes after specific interventions (SMD 0.193, 95% confidence interval (CI): -0.094 to 0.481, P = 0.188). From subgroup analyses, ERV provided significantly improved oxygenation only with laparoscopy (SMD 0.425, 95% CI: 0.167-0.682, P = 0.001). At 60 minutes after the specific interventions, ERV improved oxygenation significantly in the overall analysis (SMD 0.447, 95% CI: 0.209-0.685, P < 0.001) as well as in the subgroup analyses with OLV (SMD 0.328, 95% CI: 0.011-0.644, P = 0.042) and laparoscopy (SMD 0.668, 95% CI: 0.052-1.285, P = 0.034). ERV provided lower peak airway pressure (Ppeak) and plateau airway pressure (Pplat) than CRV, regardless of the type of intervention. The relatively small number of the included articles and their heterogeneity could be the main limitations. ERV improved oxygenation at all of the

  5. Use of formal and informal care among people with prolonged fatigue: a review of the literature.

    PubMed Central

    Elliott, H

    1999-01-01

    Prolonged fatigue is a common symptom in the community and a common complaint in GPs' surgeries. The current consensus is that prolonged fatigue is most appropriately managed within primary care but that quality of care is patchy. Diagnosis is difficult and there is no conclusive evidence about effective treatment. This can lead to confusion and controversy among lay people and health professionals alike. Although the value of a positive doctor-patient relationship is emphasized, general practice consultations are frequently experienced as difficult by both parties. Moreover, little is known about how people access other sources of care and information about prolonged fatigue, such as alternative medicine, self-help groups, lay others, and self care, in conjunction with or as an alternative to care from health professionals. This paper reviews the literature on the nature and extent of the problem prolonged fatigue represents for primary care, and on the use of formal and informal care for prolonged fatigue. PMID:10326269

  6. Prevention of B220+ T cell expansion and prolongation of lifespan induced by Lactobacillus casei in MRL/lpr mice

    PubMed Central

    Mike, A; Nagaoka, N; Tagami, Y; Miyashita, M; Shimada, S; Uchida, K; Nanno, M; Ohwaki, M

    1999-01-01

    We examined the therapeutic effect of heat-killed Lactobacillus casei (LC) on MRL/lpr mice. Ingestion of a diet containing 0.05% (w/w) LC from the weaning period prolonged the lifespan and tended to reduce the proportion of B220+ T cells in the spleen and mesenteric lymph nodes (MLN) of MRL/lpr mice. When LC was intraperitoneally injected once a week after the age of 8 weeks, I-A− macrophages accumulated in the spleen as well as the peritoneum and macrophage progenitors increased in the bone marrow. Moreover, the amount of IL-6 mRNA in peritoneal macrophages was reduced by LC injection. Splenocytes from LC-injected MRL/lpr mice exhibited lower proliferative responses to mitogens than those from control MRL/lpr mice and the increase in number of B220+ T cells in the spleen and MLN was prevented by LC injection. However, LC injection affected neither expression of interferon-gamma (IFN-γ) and IL-4 mRNAs nor proliferative capacities of splenic T cells. Our findings demonstrate that LC injection accelerates macrophage recruitment and prevents the expansion of B220+ T cells without affecting the functions of T cells in MRL/lpr mice. These immunological modulations induced by LC may lead to prolongation of the lifespan of MRL/lpr mice. PMID:10444272

  7. Prolonged Nightly Fasting and Breast Cancer Risk: Findings from NHANES (2009-2010)

    PubMed Central

    Marinac, Catherine R.; Natarajan, Loki; Sears, Dorothy D.; Gallo, Linda C.; Hartman, Sheri J.; Arredondo, Elva; Patterson, Ruth E.

    2015-01-01

    Background A novel line of research has emerged suggesting that daily feeding-fasting schedules that are synchronized with sleep-wake cycles have metabolic implications that are highly relevant to breast cancer. We examined associations of nighttime fasting duration with biomarkers of breast cancer risk among women in the 2009-2010 U.S. National Health and Nutrition Examination Survey. Methods Dietary, anthropometric and HbA1c data were available for 2,212 women, and 2-hour postprandial glucose concentrations were available for 1,066 women. Nighttime fasting duration was calculated using 24-hour food records. Separate linear regression models examined associations of nighttime fasting with HbA1c and 2-hour glucose concentrations. Logistic regression modeled associations of nighttime fasting with elevated HbA1c (HbA1c ≥ 39 mmol/mol or 5.7%) and elevated 2-hour glucose (glucose ≥ 140 mg/dL). All models adjusted for age, education, race/ethnicity, BMI, total kcal intake, evening kcal intake, and the number of eating episodes per day. Results Each 3-hour increase in nighttime fasting (roughly one standard deviation) was associated with a 4% lower 2-hour glucose measurement (β 0.96, 95% CI 0.93-1.00; p<0.05), and a non-statistically significant decrease in HbA1c. Logistic regression models indicate that each 3-hour increase in nighttime fasting duration was associated with roughly a 20% reduced odds of elevated HbA1c (OR 0.81, 95% CI 0.68, 0.97; p<0.05) and non-significantly reduced odds of elevated 2-hour glucose. Conclusions A longer nighttime duration was significantly associated with improved glycemic regulation. Impact Randomized trials are needed to confirm whether prolonged nighttime fasting could improve biomarkers of glucose control, thereby reducing breast cancer risk. PMID:25896523

  8. Skeletal muscle atrophy occurs slowly and selectively during prolonged aestivation in Cyclorana alboguttata (Gunther 1867).

    PubMed

    Mantle, Beth L; Hudson, Nicholas J; Harper, Gregory S; Cramp, Rebecca L; Franklin, Craig E

    2009-11-01

    We investigated the effect of prolonged immobilisation of six and nine months duration on the morphology and antioxidant biochemistry of skeletal muscles in the amphibian aestivator Cyclorana alboguttata. We hypothesised that, in the event of atrophy occurring during aestivation, larger jumping muscles were more likely to be preserved over smaller non-jumping muscles. Whole muscle mass (g), muscle cross-sectional area (CSA) (microm(2)), water content (%) and myofibre number (per mm(2)) remained unchanged in the cruralis muscle after six to nine months of aestivation; however, myofibre area (microm(2)) was significantly reduced. Whole muscle mass, water content, myofibre number and myofibre CSA remained unchanged in the gastrocnemius muscle after six to nine months of aestivation. However, iliofibularis dry muscle mass, whole muscle CSA and myofibre CSA was significantly reduced during aestivation. Similarly, sartorius dry muscle mass, water content and whole muscle CSA was significantly reduced during aestivation. Endogenous antioxidants were maintained at control levels throughout aestivation in all four muscles. The results suggest changes to muscle morphology during aestivation may occur when lipid reserves have been depleted and protein becomes the primary fuel substrate for preserving basal metabolic processes. Muscle atrophy as a result of this protein catabolism may be correlated with locomotor function, with smaller non-jumping muscles preferentially used as a protein source during fasting over larger jumping muscles. Higher levels of endogenous antioxidants in the jumping muscles may confer a protective advantage against oxidative damage during aestivation; however, it is not clear whether they play a role during aestivation or upon resumption of normal metabolic activity.

  9. Potential for reducing on-farm greenhouse gas and ammonia emissions from dairy cows with prolonged diet alterations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Animal agriculture significantly contributes to gaseous emissions that are implicated in global climate change and local environmental problems. Dairy cows specifically are responsible for enteric methane (CH4) emissions, and produce nitrous oxide (N2O) and ammonia (NH3) emissions from manure. Here,...

  10. Stable Carbon Isotope Evidence for Reduced Feeding of Gulf of Mexico Sturgeon during Their Prolonged River Residence Period

    NASA Astrophysics Data System (ADS)

    Gu, B.; Schell, D. M.; Frazer, T.; Hoyer, M.; Chapman, F. A.

    2001-09-01

    Stable carbon isotope ratios were used to delineate food sources for Gulf of Mexico sturgeon ( Acipenser oxyrinchus de sotoi), an anadromous fish that migrates between Gulf of Mexico and the coastal rivers in south-east U.S.A. The large difference in isotope ratios (˜11‰) between freshwater food sources and fish muscle tissue suggests that the Gulf of Mexico sturgeon do not feed significantly in fresh waters. Isotope ratio data from this study and also from the literature indicate that the growth of Gulf of Mexico sturgeon is almost entirely supported by coastal marine food sources. It is likely that Gulf of Mexico sturgeon use the cool springs that seep into the river as a thermal refuge during their river residence in summer and that thermal barriers may prevent the fish from exploiting the rich food sources available in the warmer portions of the Suwannee River.

  11. [Possible ramifications of prolonged standing at the workplace and its association with the development of chronic venous insufficiency].

    PubMed

    Shai, Avi; Karakis, Isabella; Shemesh, David

    2007-09-01

    The issue of working conditions and their health ramifications have recently been raised on the public agenda in Israel with special emphasis on occupations requiring prolonged standing. This review article discusses the physiological and medical aspects of prolonged standing in the workplace. Searching the literature, 19 studies were found which specifically examined the effect of prolonged standing versus prolonged sitting at work. Most of these studies suggested that prolonged standing may result in the development and aggravation of chronic venous insufficiency. The association between prolonged standing and venous insufficiency was found to be more pronounced in women than in men.

  12. The role of radiogenic heat in prolonged intraplate reworking: The Capricorn Orogen explained?

    NASA Astrophysics Data System (ADS)

    Korhonen, Fawna J.; Johnson, Simon P.

    2015-10-01

    Links between intraplate crustal deformation and the thermal regime of the lithosphere have been investigated using numerical models, but these conceptual models must be tested using well-constrained natural systems. The Proterozoic Capricorn Orogen of Western Australia is ideally suited for such a study; after arc accretion, it records a protracted history of intracrustal differentiation and over one billion years of subsequent tectonic reworking. The early addition of juvenile arc material initially reduced the heat production of the crust, whereas subsequent recycling of the deep crust ultimately produced radiogenic granites in the shallow crust. Using whole rock and magmatic zircon compositions, we show that the shallow crust of the Capricorn Orogen has been progressively enriched in heat-producing elements with time. The high heat production is mainly controlled by thorium, concentrated in LREE-enriched phosphates that grew during the late stages of crystallization of crustally-derived granites. Using a numerical model, we investigate the thermal effects of this evolved crustal stratification and compare them with quantitative data on the pressure-temperature-time evolution of a non-magmatic Mesoproterozoic reworking event. The results provide new information concerning the process by which the thermal conditions necessary for the reworking of orogenic crust are generated and sustained for prolonged timescales (>110 Ma). Furthermore, we demonstrate that perturbations to the radiogenic crust lead to warmer geotherms and consequent lithospheric weakening, which has a fundamental control on intraplate reworking of long-lived orogens.

  13. On Prolonging Network Lifetime through Load-Similar Node Deployment in Wireless Sensor Networks

    PubMed Central

    Li, Qiao-Qin; Gong, Haigang; Liu, Ming; Yang, Mei; Zheng, Jun

    2011-01-01

    This paper is focused on the study of the energy hole problem in the Progressive Multi-hop Rotational Clustered (PMRC)-structure, a highly scalable wireless sensor network (WSN) architecture. Based on an analysis on the traffic load distribution in PMRC-based WSNs, we propose a novel load-similar node distribution strategy combined with the Minimum Overlapping Layers (MOL) scheme to address the energy hole problem in PMRC-based WSNs. In this strategy, sensor nodes are deployed in the network area according to the load distribution. That is, more nodes shall be deployed in the range where the average load is higher, and then the loads among different areas in the sensor network tend to be balanced. Simulation results demonstrate that the load-similar node distribution strategy prolongs network lifetime and reduces the average packet latency in comparison with existing nonuniform node distribution and uniform node distribution strategies. Note that, besides the PMRC structure, the analysis model and the proposed load-similar node distribution strategy are also applicable to other multi-hop WSN structures. PMID:22163809

  14. A change of task prolongs early processes: evidence from ERPs in lexical tasks.

    PubMed

    Elchlepp, Heike; Lavric, Aureliu; Monsell, Stephen

    2015-04-01

    Switching tasks costs time. Allowing time to prepare reduces the cost, but usually leaves an irreducible "residual cost." Most accounts of this residual cost locate it within the response-selection stage of processing. To determine which processing stage is affected, we measured event-related potentials (ERPs) as participants performed a reading task or a perceptual judgment task, and examined the effect of a task switch on early markers of lexical processing. A task cue preceding a string of blue and red letters instructed the participant either to read the letter string (for a semantic classification in Experiment 1, and a lexical decision in Experiment 2) or to judge the symmetry of its color pattern. In Experiment 1, having to switch to the reading task delayed the evolution of the effect of word frequency on the reading task ERP by a substantial fraction of the effect on reaction time (RT). In Experiment 2, a task switch delayed the onset of the effect of lexical status on the ERP by about the same extent that it prolonged the RT. These effects indicate an early locus of (most of) the residual switch cost: We propose that this reflects a form of task-related attentional inertia. Other findings have implications for the automaticity of lexical access: Effects of frequency, lexicality, and orthographic familiarity on ERPs in the symmetry task indicated involuntary, but attenuated, orthographic and lexical processing even when attention was focused on a nonlexical property.

  15. Dramatic neuronal rescue with prolonged selective head cooling after ischemia in fetal lambs.

    PubMed Central

    Gunn, A J; Gunn, T R; de Haan, H H; Williams, C E; Gluckman, P D

    1997-01-01

    Hypothermia has been proposed as a neuroprotective strategy. However, short-term cooling after hypoxia-ischemia is effective only if started immediately during resuscitation. The aim of this study was to determine whether prolonged head cooling, delayed into the late postinsult period, improves outcome from severe ischemia. Unanesthetized near term fetal sheep were subject to 30 min of cerebral ischemia. 90 min later they were randomized to either cooling (n = 9) or sham cooling (n = 7) for 72 h. Intrauterine cooling was induced by a coil around the fetal head, leading initially to a fall in extradural temperature of 5-10 degrees C, and a fall in esophageal temperature of 1.5-3 degrees C. Cooling was associated with mild transient systemic metabolic effects, but not with hypotension or altered fetal heart rate. Cerebral cooling reduced secondary cortical cytotoxic edema (P < 0.001). After 5 d of recovery there was greater residual electroencephalogram activity (-5.2+/-1.6 vs. -15.5+/-1.5 dB, P < 0.001) and a dramatic reduction in the extent of cortical infarction and neuronal loss in all regions assessed (e.g., 40 vs. 99% in the parasagittal cortex, P < 0.001). Selective head cooling, maintained throughout the secondary phase of injury, is noninvasive and safe and shows potential for improving neonatal outcome after perinatal asphyxia. PMID:9005993

  16. Survival and recovery of Phaeocystis antarctica (Prymnesiophyceae) from prolonged darkness and freezing.

    PubMed

    Tang, Kam W; Smith, Walker O; Shields, Amy R; Elliott, David T

    2009-01-07

    The colony-forming haptophyte Phaeocystis antarctica is an important primary producer in the Ross Sea, and must survive long periods of darkness and freezing temperature in this extreme environment. We conducted experiments on the responses of P. antarctica-dominated phytoplankton assemblages to prolonged periods of darkness and freezing. Chlorophyll and photosynthetic capacity of the alga declined nonlinearly and independently of each other in the dark, and darkness alone would potentially reduce photosynthetic capacity by only 60 per cent over 150 days (approximately the length of the Antarctic winter in the southern Ross Sea). The estimated reduction of colonial mucous carbon is higher than that of colonial cell carbon, suggesting metabolism of the colonial matrix in the dark. The alga quickly resumed growth upon return to light. Phaeocystis antarctica also survived freezing, although longer freezing durations lengthened the lag before growth resumption. Particulate dimethylsulfoniopropionate relative to chlorophyll increased upon freezing and decreased upon darkness. Taken together, the abilities of P. antarctica to survive freezing and initiate growth quickly after darkness may provide it with the capability to survive in both the ice and the water column, and help explain its repeated dominance in austral spring blooms in the Ross Sea and elsewhere in the Southern Ocean.

  17. Prolonged exposure of cholestatic rats to complete dark inhibits biliary hyperplasia and liver fibrosis.

    PubMed

    Han, Yuyan; Onori, Paolo; Meng, Fanyin; DeMorrow, Sharon; Venter, Julie; Francis, Heather; Franchitto, Antonio; Ray, Debolina; Kennedy, Lindsey; Greene, John; Renzi, Anastasia; Mancinelli, Romina; Gaudio, Eugenio; Glaser, Shannon; Alpini, Gianfranco

    2014-11-01

    Biliary hyperplasia and liver fibrosis are common features in cholestatic liver disease. Melatonin is synthesized by the pineal gland as well as the liver. Melatonin inhibits biliary hyperplasia of bile duct-ligated (BDL) rats. Since melatonin synthesis (by the enzyme serotonin N-acetyltransferase, AANAT) from the pineal gland increases after dark exposure, we hypothesized that biliary hyperplasia and liver fibrosis are diminished by continuous darkness via increased melatonin synthesis from the pineal gland. Normal or BDL rats (immediately after surgery) were housed with light-dark cycles or complete dark for 1 wk before evaluation of 1) the expression of AANAT in the pineal gland and melatonin levels in pineal gland tissue supernatants and serum; 2) biliary proliferation and intrahepatic bile duct mass, liver histology, and serum chemistry; 3) secretin-stimulated ductal secretion (functional index of biliary growth); 4) collagen deposition, liver fibrosis markers in liver sections, total liver, and cholangiocytes; and 5) expression of clock genes in cholangiocytes. In BDL rats exposed to dark there was 1) enhanced AANAT expression/melatonin secretion in pineal gland and melatonin serum levels; 2) improved liver morphology, serum chemistry and decreased biliary proliferation and secretin-stimulated choleresis; and 4) decreased fibrosis and expression of fibrosis markers in liver sections, total liver and cholangiocytes and reduced biliary expression of the clock genes PER1, BMAL1, CLOCK, and Cry1. Thus prolonged dark exposure may be a beneficial noninvasive therapeutic approach for the management of biliary disorders.

  18. A novel oromucosal prolonged release mucoadhesive suspension by one step spray coagulation method.

    PubMed

    Cilurzo, Francesco; Gennari, Chiara G M; Selmin, Francesca; Musazzi, Umberto M; Rumio, Cristiano; Minghetti, Paola

    2013-06-01

    An oromucosal mucoadhesive suspension (OMS) able to combine the peculiarities of prolonged release mucoadhesive microparticles with those of an immediate release oromucosal solution is described. Microparticles were obtained by ionotropic gelation of alginate blended with another mucoadhesive material in a one step process where the cross-linking bath constituted the suspension vehicle. The effects of formulation and processing conditions on OMS performances were measured in-vitro determining the enhancement of drug penetration in buccal porcine mucosa and inhibition of tooth plaque formation using flurbiprofen and delmopinol as model drugs, respectively. Well-formed and spherical microparticles were obtained combining alginate with carbomer; linear dependence of particle size from the feed composition, viscosity and atomization pressure was found. As demonstrated by using FITC-labelled microparticles, the system remained onto the buccal mucosa at least for a six hour period. As a consequence, 0.1% flurbiprofen OMS guaranteed a concentration of flurbiprofen into buccal porcine mucosa over 6 hours comparable to 0.25% flurbiprofen reference solution, allowing a potential reduction of the 60% administered dose. The use of in-house made artificial mouth revealed that the once-a-day administration of 0.1% delmopinol OMS was as effective in plaque inhibition as the 0.2% delmopinol reference solution product given twice-a-day. These results suggested that the development of bioadhesive oromucosal suspensions, localizing the drug into buccal cavity, can reduce regimen and administrated dose.

  19. Coral symbioses under prolonged environmental change: living near tolerance range limits

    PubMed Central

    Sampayo, Eugenia M.; Ridgway, Tyrone; Franceschinis, Lorenzo; Roff, George; Hoegh-Guldberg, Ove; Dove, Sophie

    2016-01-01

    As climate change progresses, understanding the long-term response of corals and their endosymbionts (Symbiodinium) to prolonged environmental change is of immediate importance. Here, a total of 1152 fragments from 72 colonies of three common coral species (Stylophora pistillata, Pocillopora damicornis, Seriatopora hystrix) underwent a 32-month reciprocal depth transplantation. Genetic analysis showed that while S. hystrix maintained its generalist symbiont, some S. pistillata and P. damicornis underwent temporary changes in resident symbionts immediately after stress (transplantation; natural bleaching). These temporary changes were phylogenetically constrained to ‘host-compatible’ symbionts only and reversion to original symbionts occurred within 7 to 12 months, indicating long-term fidelity and stability of adult symbioses. Measurements of symbiont photo-physiology (dark adapted yield, pressure over photosystem II) and coral health (host protein, bleaching status, mortality) indicated a broad acclimatory capacity. However, this came at an apparent energetic expense as disproportionate mortality amongst symbioses that persisted outside their distribution range was observed following a natural bleaching event. As environmental changes due to climate change become more continuous in nature, sub-lethal effects linked to the existence near tolerance range limits coupled with the inability of adult coral colonies to change resident symbionts makes corals particularly susceptible to additional environmental fluctuations or stress events and reduces the resilience of coral populations. PMID:27805069

  20. Venom of a parasitoid wasp induces prolonged grooming in the cockroach

    PubMed

    Weisel-Eichler; Haspel; Libersat

    1999-04-01

    The parasitoid wasp Ampulex compressa hunts cockroaches Periplaneta americana, stinging them first in the thorax and then in the head, the sting penetrating towards the subesophageal ganglion. After being stung the cockroach grooms almost continuously for approximately 30 min, performing all the normal components of grooming behavior. This excessive grooming is only seen after the head sting and cannot be attributed to stress, to contamination of the body surface or to systemic or peripheral effects. This suggests that the venom is activating a neural network for grooming. We suggest that the venom induces prolonged grooming by stimulating dopamine receptors in the cockroach, for the following reasons. (1) Reserpine, which causes massive release of monoamines, induces excessive grooming. (2) Dopamine injected into the hemocoel also induces excessive grooming and is significantly more effective than octopamine or serotonin. In addition, the dopamine agonist SKF 82958 induces excessive grooming when injected directly into the subesophageal ganglion. (3) Injection of the dopamine antagonist flupenthixol greatly reduces venom-induced grooming. (4) Dopamine, or a dopamine-like substance, is present in the venom.

  1. Biophysical probing of Spartina maritima photo-system II changes during prolonged tidal submersion periods.

    PubMed

    Duarte, B; Santos, D; Marques, J C; Caçador, I

    2014-04-01

    Submergence is one of the major constrains affecting wetland plants, with inevitable impacts on their physiology and productivity. Global warming as a driving force of sea level rise, tend to increase the submersion periods duration. Photosynthesis biophysical probing arise as an important tool to understand the energetics underlying plant feedback to these constrains. As in previous studies with Spartina maritima, there was no inhibition of photosynthetic activity in submerged individuals. Comparing both donor and acceptor sides of the PSII, the first was more severely affected during submersion, driven by the inactivation of the OEC with consequent impairment of the ETC. Although this apparent damage in the PSII donor side, the electron transport per active reaction centre was not substantially affected, indicating that this reduction in the electron flow is accompanied by a proportional increase in the number of active reaction centres. These conditions lead to the accumulation of excessive reducing power, source of damaging ROS, counteracted by efficient energy dissipation processes and anti-oxidant enzymatic defences. This way, S. maritima appears as a well-adapted species with an evident photochemical plasticity towards submersion, allowing it to maintain its photosynthetic activity even during prolonged submersion periods.

  2. Suppression of endothelial t-PA expression by prolonged high laminar shear stress

    SciTech Connect

    Ulfhammer, Erik; Carlstroem, Maria; Bergh, Niklas; Larsson, Pia; Karlsson, Lena; Jern, Sverker

    2009-02-06

    Primary hypertension is associated with an impaired capacity for acute release of endothelial tissue-type plasminogen activator (t-PA), which is an important local protective response to prevent thrombus extension. As hypertensive vascular remodeling potentially results in increased vascular wall shear stress, we investigated the impact of shear on regulation of t-PA. Cultured human endothelial cells were exposed to low ({<=}1.5 dyn/cm{sup 2}) or high (25 dyn/cm{sup 2}) laminar shear stress for up to 48 h in two different experimental models. Using real-time RT-PCR and ELISA, shear stress was observed to time and magnitude-dependently suppress t-PA transcript and protein secretion to approximately 30% of basal levels. Mechanistic experiments revealed reduced nuclear protein binding to the t-PA specific CRE element (EMSA) and an almost completely abrogated shear response with pharmacologic JNK inhibition. We conclude that prolonged high laminar shear stress suppresses endothelial t-PA expression and may therefore contribute to the enhanced risk of arterial thrombosis in hypertensive disease.

  3. Simple rain-shelter cultivation prolongs accumulation period of anthocyanins in wine grape berries.

    PubMed

    Li, Xiao-Xi; He, Fei; Wang, Jun; Li, Zheng; Pan, Qiu-Hong

    2014-09-17

    Simple rain-shelter cultivation is normally applied during the grape growth season in continental monsoon climates aiming to reduce the occurrence of diseases caused by excessive rainfall. However, whether or not this cultivation practice affects the composition and concentration of phenolic compounds in wine grapes remains unclear. The objective of this study was to investigate the effect of rain-shelter cultivation on the accumulation of anthocyanins in wine grapes (Vitis vinifera L. Cabernet Sauvignon) grown in eastern China. The results showed that rain-shelter cultivation, compared with the open-field, extended the period of rapid accumulation of sugar, increased the soluble solid content in the grape berries, and delayed the senescence of the green leaves at harvest. The concentrations of most anthocyanins were significantly enhanced in the rain-shelter cultivated grapes, and their content increases were closely correlated with the accumulation of sugar. However, the compositions of anthocyanins in the berries were not altered. Correspondingly, the expressions of VvF3'H, VvF3'5'H, and VvUFGT were greatly up-regulated and this rising trend appeared to continue until berry maturation. These results suggested that rain-shelter cultivation might help to improve the quality of wine grape berries by prolonging the life of functional leaves and hence increasing the assimilation products.

  4. Prolonged cultivation of hippocampal neural precursor cells shifts their differentiation potential and selects for aneuploid cells.

    PubMed

    Nguyen, The Duy; Widera, Darius; Greiner, Johannes; Müller, Janine; Martin, Ina; Slotta, Carsten; Hauser, Stefan; Kaltschmidt, Christian; Kaltschmidt, Barbara

    2013-12-01

    Neural precursor cells (NPCs) are lineage-restricted neural stem cells with limited self-renewal, giving rise to a broad range of neural cell types such as neurons, astrocytes, and oligodendrocytes. Despite this developmental potential, the differentiation capacity of NPCs has been controversially discussed concerning the trespassing lineage boundaries, for instance resulting in hematopoietic competence. Assessing their in vitro plasticity, we isolated nestin+/Sox2+, NPCs from the adult murine hippocampus. In vitro-expanded adult NPCs were able to form neurospheres, self-renew, and differentiate into neuronal, astrocytic, and oligodendrocytic cells. Although NPCs cultivated in early passage efficiently gave rise to neuronal cells in a directed differentiation assay, extensively cultivated NPCs revealed reduced potential for ectodermal differentiation. We further observed successful differentiation of long-term cultured NPCs into osteogenic and adipogenic cell types, suggesting that NPCs underwent a fate switch during culture. NPCs cultivated for more than 12 passages were aneuploid (abnormal chromosome numbers such as 70 chromosomes). Furthermore, they showed growth factor-independent proliferation, a hallmark of tumorigenic transformation. In conclusion, our findings substantiate the lineage restriction of NPCs from adult mammalian hippocampus. Prolonged cultivation results, however, in enhanced differentiation potential, which may be attributed to transformation events leading to aneuploid cells.

  5. Mitochondrial responses to prolonged anoxia in brain of red-eared slider turtles

    PubMed Central

    Pamenter, Matthew E.; Gomez, Crisostomo R.; Richards, Jeffrey G.; Milsom, William K.

    2016-01-01

    Mitochondria are central to aerobic energy production and play a key role in neuronal signalling. During anoxia, however, the mitochondria of most vertebrates initiate deleterious cell death cascades. Nonetheless, a handful of vertebrate species, including some freshwater turtles, are remarkably tolerant of low oxygen environments and survive months of anoxia without apparent damage to brain tissue. This tolerance suggests that mitochondria in the brains of such species are adapted to withstand prolonged anoxia, but little is known about potential neuroprotective responses. In this study, we address such mechanisms by comparing mitochondrial function between brain tissues isolated from cold-acclimated red-eared slider turtles (Trachemys scripta elegans) exposed to two weeks of either normoxia or anoxia. We found that brain mitochondria from anoxia-acclimated turtles exhibited a unique phenotype of remodelling relative to normoxic controls, including: (i) decreased citrate synthase and F1FO-ATPase activity but maintained protein content, (ii) markedly reduced aerobic capacity, and (iii) mild uncoupling of the mitochondrial proton gradient. These data suggest that turtle brain mitochondria respond to low oxygen stress with a unique suite of changes tailored towards neuroprotection. PMID:26763217

  6. Arabidopsis growth under prolonged high temperature and water deficit: independent or interactive effects?

    PubMed

    Vile, Denis; Pervent, Marjorie; Belluau, Michaël; Vasseur, François; Bresson, Justine; Muller, Bertrand; Granier, Christine; Simonneau, Thierry

    2012-04-01

    High temperature (HT) and water deficit (WD) are frequent environmental constraints restricting plant growth and productivity. These stresses often occur simultaneously in the field, but little is known about their combined impacts on plant growth, development and physiology. We evaluated the responses of 10 Arabidopsis thaliana natural accessions to prolonged elevated air temperature (30 °C) and soil WD applied separately or in combination. Plant growth was significantly reduced under both stresses and their combination was even more detrimental to plant performance. The effects of the two stresses were globally additive, but some traits responded specifically to one but not the other stress. Root allocation increased in response to WD, while reproductive allocation, hyponasty and specific leaf area increased under HT. All the traits that varied in response to combined stresses also responded to at least one of them. Tolerance to WD was higher in small-sized accessions under control temperature and HT and in accessions with high biomass allocation to root under control conditions. Accessions that originate from sites with higher temperature have less stomatal density and allocate less biomass to the roots when cultivated under HT. Independence and interaction between stresses as well as the relationships between traits and stress responses are discussed.

  7. Prolonged exposure to FLT3 inhibitors leads to resistance via activation of parallel signaling pathways

    PubMed Central

    Piloto, Obdulio; Wright, Melissa; Brown, Patrick; Kim, Kyu-Tae; Levis, Mark; Small, Donald

    2007-01-01

    Continuous treatment of malignancies with tyrosine kinase inhibitors (TKIs) may select for resistant clones (ie, imatinib mesylate). To study resistance to TKIs targeting FLT3, a receptor tyrosine kinase that is frequently mutated in acute myelogenous leukemia (AML), we developed resistant human cell lines through prolonged coculture with FLT3 TKIs. FLT3 TKI-resistant cell lines and primary samples still exhibit inhibition of FLT3 phosphorylation on FLT3 TKI treatment. However, FLT3 TKI-resistant cell lines and primary samples often show continued activation of downstream PI3K/Akt and/or Ras/MEK/MAPK signaling pathways as well as continued expression of genes involved in FLT3-mediated cellular transformation. Inhibition of these signaling pathways restores partial sensitivity to FLT3 TKIs. Mutational screening of FLT3 TKI-resistant cell lines revealed activating N-Ras mutations in 2 cell lines that were not present in the parental FLT3 TKI-sensitive cell line. Taken together, these data indicate that FLT3 TKI-resistant cells most frequently become FLT3 independent because of activation of parallel signaling pathways that provide compensatory survival/proliferation signals when FLT3 is inhibited. Anti-FLT3 mAb treatment was still cytotoxic to FLT3 TKI-resistant clones. An approach combining FLT3 TKIs with anti-FLT3 antibodies and/or inhibitors of important pathways downstream of FLT3 may reduce the chances of developing resistance. PMID:17047150

  8. Effect of prolonged hypokinesia on tissue blood flow

    NASA Technical Reports Server (NTRS)

    Levites, Z. P.; Fedotova, V. F.

    1979-01-01

    The influence of hypokinesia on the blood flow in the tissues of rabbits was studied. Motor activity of animals was restricted during 90 days and blood flow recorded through resorption rate of NaI-131. Perfusion of tissues under the influence of hypokinesia was found to be reduced.

  9. Symptom Severity Predicts Prolonged Recovery after Sport-Related Concussion: Age and Amnesia Do Not

    PubMed Central

    Meehan, William P.; Mannix, Rebekah C.; Stracciolini, Andrea; Elbin, R.J.; Collins, Michael W.

    2013-01-01

    Objective To identify predictors of prolonged symptoms for athletes who sustain concussions. Study design We conducted a multi-center, prospective, cohort study of patients in 2 sport concussion clinics. Possible predictors of prolonged symptoms from concussion were compared between two groups: those whose symptoms resolved within 28 days and those whose symptoms persisted beyond 28 days. Candidate predictor variables were entered into a logistic regression model that was used to generate adjusted odds ratios. Results During the study period, 182 patients met inclusion criteria. The mean age was 15.2 years (SD 3.04 years). Over a third (N=65) of patients underwent computerized neurocognitive testing on their initial visit. In univariate analyses, Post Concussion Symptom Scale (PCSS) score and all composite scores on computerized neurocognitive testing appeared to be associated with prolonged symptom duration. Sex, age, loss of consciousness at time of injury and amnesia at time of injury were not associated with prolonged symptom duration. After adjusting for potential confounding, however, only total score on the PCSS score was associated with the odds of suffering prolonged symptoms. Conclusions After adjusting for other potential confounding variables, only total score on the PCSS was associated with the odds of suffering prolonged symptoms from sport-related concussions; age and amnesia were not. Further efforts to develop clinical tools for predicting which athletes will suffer prolonged recoveries after concussion should focus on initial symptom score. PMID:23628374

  10. Prolonged bradycardia, asystole and outcome of high spinal cord injury patients: Risk factors and management

    PubMed Central

    Shaikh, Nissar; Rhaman, M. A.; Raza, Ali; Shabana, Adel; Malstrom, Mahommad Faisal; Al-Sulaiti, Ghanem

    2016-01-01

    Background: High spinal cord injury (HSCI) is one of the devastating traumatic injuries. 80% of these patients are young male, and 93% will have major neurological disabilities. There is a paucity of literature about prolonged bradycardia in HSCI patients. The aim of this study was to know the prevalence, risk factors, precipitating factors for prolonged bradycardia in the HSCI patients. Materials and Methods: All patients who were admitted to the Intensive Care Unit (ICU) of a tertiary hospital, with spinal cord injury above level of dorsal (D4) were enrolled in this study prospectively. Patient's demographic data, mechanism, level and type of spinal injury, associated injuries, injury severity score (ISS), spinal shock, vasopressors used, time of occurrence of bradycardia, treatment for bradycardia, precipitating as well as risk factors and outcome were recorded. Results: During the study period, a total of 138 patients were admitted to the ICU with HSCI. Majority of patients were male. The most frequently associated injury in these patients was skeletal fractures (38.4%). Most common complication was pneumonia 56 (41%). Forty-five (33%) of the total patients had prolonged bradycardia; 87% of these patients had pneumonia when bradycardia occurred. 53.4% had cardiac asystole. 29 (21%) patients had bradycardia at the time of endotracheal suctioning, whereas 27 (20%) patients developed bradycardia at the time of positioning. Majority of the patients were managed conservatively. Those HSCI patients who developed prolonged bradycardia, their ISS score was statistically higher, ICU and hospital stay was significantly higher compared with those HSCI patient who did not have prolonged bradycardia. Multivariate analysis revealed that hypotension on admission; pneumonia, and tracheostomy were risk factors for the development of prolonged bradycardia in HSCI patients. Conclusion: Prolonged bradycardia was associated with significantly higher incidence of asystole

  11. The Significance of Prolonged and Saddleback Fever in Hospitalised Adult Dengue

    PubMed Central

    Thein, Tun-Linn; Leo, Yee-Sin; Lye, David C.

    2016-01-01

    Dengue fever is gaining importance in Singapore with an increase in the number of cases and mortality in recent years. Although prolonged and saddleback fever have been reported in dengue fever, there are no specific studies on their significance in dengue. This study aims to examine the prevalence of prolonged and saddleback fever in dengue as well as their associations with dengue severity. A total of 2843 polymerase-chain reaction (PCR) confirmed dengue patients admitted to Tan Tock Seng Hospital from 2004 to 2008 were included in the study. Sixty-nine percent of them were male with a median age of 34 years. Prolonged fever (fever > 7 days duration) was present in 572 (20.1%) of patients. Dengue hemorrhagic fever (DHF), dengue shock syndrome (DSS) and severe dengue (SD) were significantly more likely to occur in patients with prolonged fever. Mucosal bleeding, anorexia, diarrhea, abdominal pain, nausea or vomiting, lethargy, rash, clinical fluid accumulation, hepatomegaly, nosocomial infection, leukopenia, higher neutrophil count, higher hematocrit, higher alanine transaminase (ALT) and aspartate transaminase (AST), higher creatinine, lower protein and prolonged activated partial thromboplastin time (APTT) were significantly associated with prolonged fever but not platelet count or prothrombin time (PT). Saddleback fever was present in 165 (5.8%). Although DHF and SD were more likely to occur in patients in those with saddleback fever, DSS was not. Compared with prolonged fever, saddleback fever did not show many significant associations except for diarrhea, abdominal pain, clinical fluid accumulation, hematocrit and platelet change, and lower systolic blood pressure. This study demonstrates that prolonged fever may be associated with various warning signs and more severe forms of dengue (SD, DSS, DHF), while saddleback fever showed associations with DHF and SD but not DSS. The presence of prolonged or saddleback fever in dengue patients should therefore prompt

  12. Population-Based Study of QT Interval Prolongation in Patients with Rheumatoid Arthritis

    PubMed Central

    Chauhan, Krati; Ackerman, Michael J.; Crowson, Cynthia S.; Matteson, Eric L.; Gabriel, Sherine E.

    2015-01-01

    Background Patients with rheumatoid arthritis (RA) are at increased risk of cardiovascular morbidity and mortality. Heart rate corrected QT interval (QTc) (which is obtained from a 12-lead electrocardiogram (ECG) and reflects ventricular repolarization duration) is a strong predictor of cardiovascular mortality. Our primary purpose is to determine the impact of QTc prolongation on mortality in RA patients. Methods A population-based inception cohort of patients with RA fulfilling 1987 ACR criteria in 1988–2007 was identified, with an age- and sex-matched comparison cohort and followed until death, migration or 12-31-2008. Data were collected on ECG variables, medications known to prolong QT interval, electrolytes, cardiovascular risk factors and disease status and RA disease characteristics. Cox proportional hazards models were used to examine QTc prolongation as predictor of mortality. Results QTc prolongation prior to RA incidence/index date was similar in RA (15%) and non-RA (18%) subjects. During follow-up, the cumulative incidence of QTc prolongation was higher among RA (48% at 20 years after RA incidence) than non-RA (38% at 20 years after index date; p= 0.004). Idiopathic QTc prolongation (excluding prolongations explained by ECG changes, medications, etc.) was marginally associated with all-cause mortality (HR: 1.28; 95% CI: 0.91–1.81, p=0.16), but was not associated with cardiovascular mortality (HR: 1.10; 95% CI:0.43–2.86, p= 0.83) in RA. Conclusion RA patients have a significantly elevated risk of developing QTc prolongation. However, idiopathic prolonged QTc was only marginally associated with all-cause mortality in RA patients. The clinical implications of these findings in RA require further study. PMID:25572282

  13. Reducing Baby Bottle Tooth Decay. A SERVE Research Brief.

    ERIC Educational Resources Information Center

    Southeastern Regional Vision for Education (SERVE), Tallahassee, FL.

    This pamphlet discusses strategies for reducing baby bottle tooth decay (BBTD) among Native American children. BBTD in infants and toddlers is a painful disease characterized by extensive decay of the upper front and side teeth. It is caused by prolonged exposure of teeth to carbohydrates, such as those contained in infant formula, milk, and fruit…

  14. Effect of initial core temperature on hyperthermic hyperventilation during prolonged submaximal exercise in the heat.

    PubMed

    Tsuji, Bun; Honda, Yasushi; Fujii, Naoto; Kondo, Narihiko; Nishiyasu, Takeshi

    2012-01-01

    We investigated whether a core temperature threshold for hyperthermic hyperventilation is seen during prolonged submaximal exercise in the heat when core temperature before the exercise is reduced and whether the evoked hyperventilatory response is affected by altering the initial core temperature. Ten male subjects performed three exercise trials at 50% of peak oxygen uptake in the heat (37°C and 50% relative humidity) after altering their initial esophageal temperature (T(es)). Initial T(es) was manipulated by immersion for 25 min in water at 18°C (Precooling), 35°C (Control), or 40°C (Preheating). T(es) after the water immersion was significantly higher in the Preheating trial (37.5 ± 0.3°C) and lower in the Precooling trial (36.1 ± 0.3°C) than in the Control trial (36.9 ± 0.3°C). In the Precooling trial, minute ventilation (Ve) showed little change until T(es) reached 37.1 ± 0.4°C. Above this core temperature threshold, Ve increased linearly in proportion to increasing T(es). In the Control trial, Ve increased as T(es) increased from 37.0°C to 38.6°C after the onset of exercise. In the Preheating trial, Ve increased from the initially elevated levels of T(es) (from 37.6 to 38.6°C) and Ve. The sensitivity of Ve to increasing T(es) above the threshold for hyperventilation (the slope of the T(es)-Ve relation) did not significantly vary across trials (Precooling trial = 10.6 ± 5.9, Control trial = 8.7 ± 5.1, and Preheating trial = 9.2 ± 6.9 L·min(-1)·°C(-1)). These results suggest that during prolonged submaximal exercise at a constant workload in humans, there is a clear core temperature threshold for hyperthermic hyperventilation and that the evoked hyperventilatory response is unaffected by altering initial core temperature.

  15. Endothelial dysfunction following prolonged sitting is mediated by a reduction in shear stress.

    PubMed

    Restaino, Robert M; Walsh, Lauren K; Morishima, Takuma; Vranish, Jennifer R; Martinez-Lemus, Luis A; Fadel, Paul J; Padilla, Jaume

    2016-03-01

    We and others have recently reported that prolonged sitting impairs endothelial function in the leg vasculature; however, the mechanism(s) remain unknown. Herein, we tested the hypothesis that a sustained reduction in flow-induced shear stress is the underlying mechanism by which sitting induces leg endothelial dysfunction. Specifically, we examined whether preventing the reduction in shear stress during sitting would abolish the detrimental effects of sitting on popliteal artery endothelial function. In 10 young healthy men, bilateral measurements of popliteal artery flow-mediated dilation were performed before and after a 3-h sitting period during which one foot was submerged in 42°C water (i.e., heated) to increase blood flow and thus shear stress, whereas the contralateral leg remained dry and served as internal control (i.e., nonheated). During sitting, popliteal artery mean shear rate was reduced in the nonheated leg (pre-sit, 42.9 ± 4.5 s(-1); and 3-h sit, 23.6 ± 3.3 s(-1); P < 0.05) but not in the heated leg (pre-sit, 38.9 ± 3.4 s(-1); and 3-h sit, 63.9 ± 16.9 s(-1); P > 0.05). Popliteal artery flow-mediated dilation was impaired after 3 h of sitting in the nonheated leg (pre-sit, 7.1 ± 1.4% vs. post-sit, 2.8 ± 0.9%; P < 0.05) but not in the heated leg (pre-sit: 7.3 ± 1.5% vs. post-sit, 10.9 ± 1.8%; P > 0.05). Collectively, these data suggest that preventing the reduction of flow-induced shear stress during prolonged sitting with local heating abolishes the impairment in popliteal artery endothelial function. Thus these findings are consistent with the hypothesis that sitting-induced leg endothelial dysfunction is mediated by a reduction in shear stress.

  16. Bindarit retards renal disease and prolongs survival in murine lupus autoimmune disease.

    PubMed

    Zoja, C; Corna, D; Benedetti, G; Morigi, M; Donadelli, R; Guglielmotti, A; Pinza, M; Bertani, T; Remuzzi, G

    1998-03-01

    As an alternative to classical immunosuppressants in experimental lupus nephritis, we looked at bindarit, 2-methyl-2-[[1-phenylmethyl)-1H-indazol-3-y1]methoxy]propanoic acid, a novel molecule devoid of immunosuppressive effects, which selectively reduces chronic inflammation in rat adjuvant arthritis. Two groups of NZB/W mice (N = 55 for each group) were given bindarit, (50 mg/kg/day p.o.) or vehicle starting at 2 months of age. Mice were sacrificed at 2, 6, 8 and 10 months or used for survival studies. Bindarit delayed the onset of proteinuria (% proteinuric mice, bindarit vs. vehicle, 6 months: 0 vs. 33% and 8 months: 7% vs. 60%, P < 0.005; 10 months: 53% vs. 80%) and significantly (P < 0.05) protected from renal function impairment (serum BUN, bindarit vs. vehicle: 8 months, 30 +/- 3 vs. 127 +/- 42; 10 months, 53 +/-5 vs. 140 +/- 37 mg/dl). Appearance of anti-DNA antibodies was retarded and survival significantly (P < 0.0001) prolonged by bindarit (% survival, bindarit vs. vehicle: 8 months, 100% vs. 80%; 10 months, 87% vs. 40%; 12 months, 27% vs. 20%). Bindarit significantly limited glomerular hypercellularity, interstitial inflammation and tubular damage. Renal expression of monocyte chemoattractant protein (MCP-1) mRNA (Northern blot) markedly increased (7 - 12-fold in 8- 10-month-old mice vs. 2-month-old) during the progression of nephritis in association with mononuclear cell infiltration. Bindarit completely prevented MCP-1 up-regulation. In another series of experiments, bindarit (0.25% and 0.5% medicated diet, N = 16 for each group) when started at 4.5 months of age in NZB/W mice improved survival in respect to untreated mice (N = 17) in a dose-dependent manner (% survival: 8 months, 94% and 100%, respectively, vs. 47%; 10 months, 75% and 100% vs. 35%; 12 months, 31% and 75% vs. 12%). Survival was even more prolonged when bindarit (0.5% medicated diet) was combined with a low dose of methylprednisolone (1.5 mg/kg i.p.), which that only partially modifies

  17. Endothelial dysfunction following prolonged sitting is mediated by a reduction in shear stress

    PubMed Central

    Restaino, Robert M.; Walsh, Lauren K.; Morishima, Takuma; Vranish, Jennifer R.; Martinez-Lemus, Luis A.; Fadel, Paul J.

    2016-01-01

    We and others have recently reported that prolonged sitting impairs endothelial function in the leg vasculature; however, the mechanism(s) remain unknown. Herein, we tested the hypothesis that a sustained reduction in flow-induced shear stress is the underlying mechanism by which sitting induces leg endothelial dysfunction. Specifically, we examined whether preventing the reduction in shear stress during sitting would abolish the detrimental effects of sitting on popliteal artery endothelial function. In 10 young healthy men, bilateral measurements of popliteal artery flow-mediated dilation were performed before and after a 3-h sitting period during which one foot was submerged in 42°C water (i.e., heated) to increase blood flow and thus shear stress, whereas the contralateral leg remained dry and served as internal control (i.e., nonheated). During sitting, popliteal artery mean shear rate was reduced in the nonheated leg (pre-sit, 42.9 ± 4.5 s−1; and 3-h sit, 23.6 ± 3.3 s−1; P < 0.05) but not in the heated leg (pre-sit, 38.9 ± 3.4 s−1; and 3-h sit, 63.9 ± 16.9 s−1; P > 0.05). Popliteal artery flow-mediated dilation was impaired after 3 h of sitting in the nonheated leg (pre-sit, 7.1 ± 1.4% vs. post-sit, 2.8 ± 0.9%; P < 0.05) but not in the heated leg (pre-sit: 7.3 ± 1.5% vs. post-sit, 10.9 ± 1.8%; P > 0.05). Collectively, these data suggest that preventing the reduction of flow-induced shear stress during prolonged sitting with local heating abolishes the impairment in popliteal artery endothelial function. Thus these findings are consistent with the hypothesis that sitting-induced leg endothelial dysfunction is mediated by a reduction in shear stress. PMID:26747508

  18. Narrative reconstruction therapy for prolonged grief disorder—rationale and case study

    PubMed Central

    Peri, Tuvia; Hasson-Ohayon, Ilanit; Garber, Sharon; Tuval-Mashiach, Rivka; Boelen, Paul A.

    2016-01-01

    Background Prolonged grief disorder (PGD) is a potentially disabling condition affecting approximately 10% of bereaved people. It has been suggested that the impaired integration of the loss memory, as expressed in recurrent memories of the loss and disorganization of memory, is involved in the development of PGD. Narrative reconstruction (NR), originally designed for the treatment of posttraumatic stress disorder (PTSD) in an integrative therapy module, and consisting of exposure to the loss memory, detailed written reconstruction of the loss memory narrative and an elaboration of the personal significance of that memory for the bereaved, has been shown to be effective in the treatment of intrusion symptoms. Objective In light of findings that cognitive behavior therapy (CBT), including cognitive restructuring and exposure, is effective in the treatment of PGD, we suggest the implementation of a somewhat novel therapy module, NR, for the treatment of intrusive phenomena in bereaved patients. Method The rationale for the implementation of NR for PGD and a case study of the treatment of a woman suffering from PGD after the death of her father are presented. Therapy took place in a university outpatient training clinic. Results Evaluations conducted before and after treatment and at a 3-month follow-up demonstrated the effectiveness of NR in reducing symptoms of PGD and depression. The analysis of spontaneous narratives recorded before and after treatment showed an increased organization of the narratives. Conclusions This case report demonstrates an adaptation of NR for the treatment of PGD. The results provide preliminary support for the effectiveness of NR for PGD. The significance of the study and its limitations are discussed. Highlights of the article Prolonged grief disorder (PGD) affects approximately ten percent of bereaved people. Narrative Reconstruction (NR), an integrative therapy module originally used for PTSD patients, was adapted for PGD. NR consists

  19. Exogenous expression of Fas-ligand or CrmA prolongs the survival in rat liver transplantation.

    PubMed

    Adachi, K; Fujino, M; Kitazawa, Y; Funeshima-Fuji, N; Takahara, S; Kimura, H; Li, X-K

    2006-10-01

    Modulation of donor organs by transfection of a gene encoding immmunosuppresive molecules has been recognized as a less toxic approach to prevent allograft rejection. Fas-ligand (FasL) plays a critical role in activation-induced cell death of activated cytotoxic lymphocytes. This may provide a potential for induction of "immune privileged sites" to escape the host immune surveillance system. Cytokine response modifier A (CrmA), a gene product of cowpox virus, blocks caspase as well as perforin/granzyme-mediated apoptotic pathways. Therefore, it may suppress intragraft apoptosis. The aim of the present study was to investigate whether transfection of FasL or CrmA genes prolonged the survival of rat liver allografts. Using the high responder rat combination of DA (RT-1(a)) donor to LEW (RT-1(1)) recipient, we performed orthotopic liver transplantation with subsequent delivery of adenoviral vectors containing FasL, CrmA, or LacZ, at a dose of 1 x 10(9) pfu via a recipient tail vein using a Cre-mediated gene expression system. Recipient survival was assessed as well as immunohistochemical examination of the grafts for anti-CD2, TUNEL, and H&E staining. Statistical analysis was performed with the Mann-Whitney U test. The therapeutic groups showed significantly prolonged recipient survival compared with the LacZ-treated control group. Histologic analysis revealed reduced hepatocyte apoptosis in the CrmA-treated group and increased apoptosis of infiltrating mononuclear cells in the FasL-treated group. These data suggested that FasL and CrmA may be potent genes to prolong rat liver allograft survival.

  20. The dexmedetomidine “augmented” sedato analgesic cocktail: An effective approach for sedation in prolonged endoscopic retrograde cholangio-pancreatography

    PubMed Central

    Mukhopadhyay, Sandip; Niyogi, Mausumi; Sarkar, Joydip; Mukhopadhyay, Basabdatta Samanta; Halder, Swapan Kumar

    2015-01-01

    Background and Aims: In absence of any published standard guideline for sedation or anesthesia practice for prolonged therapeutic “endoscopic retrograde cholangio-pancreatography (ERCP)”, safe and cost-effective sedation protocol is the need of the hour. Our study aims to evaluate the efficacy of a dexmedetomidine as an add-on for prolonged deep sedation for ERCP and to compare three deep sedation regimens regarding safety and efficacy. Material and Methods: Forty-five consecutively enrolled patients planned for therapeutic ERCP and assumed to have prolonged procedural duration (>50 min) were divided into three groups in a randomized assessor blinded fashion. Group 1 received propofol and midazolam, Group 2 received the sedato-analgesic cocktail containing ketamine-propofol-midazolam-pentazocine, and the Group 3 received sedate-analgesic cocktail plus dexmedetomidine infusion under monitoring of vital parameters and according to the judgment of the concerned anesthesiologist. Total propofol requirement, episodes of gagging, oxygen desaturation, changes in mean blood pressure (MBP), recovery and satisfaction score of endoscopist, anesthetist and patient were noted and analyzed statistically using one way ANOVA with Bonferroni correction and Chi-square test. Results: Mean propofol requirement, incidences of gagging and oxygen desaturation was significantly less in Group 2 and 3 compared to Group 1. MBP was more stable and recovery was faster in Group 3. Anesthetist's satisfaction was more with Group 2 and even more with Group 3. Conclusions: The sedato-analgesic cocktail was superior to the conventional propofol-midazolam regimen, dexmedetomidine as add-on increased the efficacy and safety of sedate-analgesic cocktail. It reduces propofol requirement, helps to maintain the patient in a safe and more stable level of sedation and increases satisfaction of the anesthetist. PMID:25948901

  1. Congenital and prolonged adult-onset deafness cause distinct degradations in neural ITD coding with bilateral cochlear implants.

    PubMed

    Hancock, Kenneth E; Chung, Yoojin; Delgutte, Bertrand

    2013-06-01

    Bilateral cochlear implant (CI) users perform poorly on tasks involving interaural time differences (ITD), which are critical for sound localization and speech reception in noise by normal-hearing listeners. ITD perception with bilateral CI is influenced by age at onset of deafness and duration of deafness. We previously showed that ITD coding in the auditory midbrain is degraded in congenitally deaf white cats (DWC) compared to acutely deafened cats (ADC) with normal auditory development (Hancock et al., J. Neurosci, 30:14068). To determine the relative importance of early onset of deafness and prolonged duration of deafness for abnormal ITD coding in DWC, we recorded from single units in the inferior colliculus of cats deafened as adults 6 months prior to experimentation (long-term deafened cats, LTDC) and compared neural ITD coding between the three deafness models. The incidence of ITD-sensitive neurons was similar in both groups with normal auditory development (LTDC and ADC), but significantly diminished in DWC. In contrast, both groups that experienced prolonged deafness (LTDC and DWC) had broad distributions of best ITDs around the midline, unlike the more focused distributions biased toward contralateral-leading ITDs present in both ADC and normal-hearing animals. The lack of contralateral bias in LTDC and DWC results in reduced sensitivity to changes in ITD within the natural range. The finding that early onset of deafness more severely degrades neural ITD coding than prolonged duration of deafness argues for the importance of fitting deaf children with sound processors that provide reliable ITD cues at an early age.

  2. Sleep-prolonging effect of Coriandrum sativum hydro-alcoholic extract in mice.

    PubMed

    Rakhshandeh, Hassan; Sadeghnia, Hamid Reza; Ghorbani, Ahmad

    2012-01-01

    The present study was planned to investigate sleep-prolonging effect of C. sativum. The hydro-alcoholic extract (HAE) and its three fractions namely water (WF), ethyl acetate (EAF) and N-butanol (NBF) were prepared from C. sativum aerial parts and administrated to mice. Also, the possible cytotoxicity of the extracts was tested using cultured PC12 cells. The HAE, EAF and NBF significantly prolonged sleep duration. Only the NBF could significantly decrease sleep latency. No decrease in the neuronal surviving was observed either by HAE or by its fractions. The present data indicate that C. sativum exert sleep-prolonging action without major neurotoxic effect.

  3. Beneficial effect of prolonged heme oxygenase 1 activation in a rat model of chronic heart failure

    PubMed Central

    Collino, Massimo; Pini, Alessandro; Mugelli, Niccolò; Mastroianni, Rosanna; Bani, Daniele; Fantozzi, Roberto; Papucci, Laura; Fazi, Marilena; Masini, Emanuela

    2013-01-01

    SUMMARY We and others have previously demonstrated that heme oxygenase 1 (HO-1) induction by acute hemin administration exerts cardioprotective effects. Here, we developed a rat model of heart failure to investigate whether a long-term induction of HO-1 by chronic hemin administration exerted protective effects. Sprague Dawley rats that underwent permanent ligation of the left coronary artery were closely monitored for survival rate analysis and sacrificed on day 28 post-operation. Administration of hemin (4 mg/kg body weight) every other day for 4 weeks induced a massive increase in HO-1 expression and activity, as shown by the increased levels of the two main metabolic products of heme degradation, bilirubin and carbon monoxide (CO). These effects were associated with significant improvement in survival and reduced the extension of myocardial damage. The ischemic hearts of the hemin-treated animals displayed reduced oxidative stress and apoptosis in comparison with the non-treated rats, as shown by the decreased levels of lipid peroxidation, free-radical-induced DNA damage, caspase-3 activity and Bax expression. Besides, chronic HO-1 activation suppressed the elevated levels of myeloperoxidase (MPO) activity, interleukin 1β (IL-1β) production and tumor necrosis factor-α (TNFα) production that were evoked by the ischemic injury, and increased the plasma level of the anti-inflammatory cytokine IL-10. Interestingly, HO-1 inhibitor zinc protoporphyrin IX (ZnPP-IX; 1 mg/kg) lowered bilirubin and CO concentrations to control values, thus abolishing all the cardioprotective effects of hemin. In conclusion, the results demonstrate that chronic HO-1 activation by prolonged administration of hemin improves survival and exerts protective effects in a rat model of myocardial ischemia by exerting a potent antioxidant activity and disrupting multiple levels of the apoptotic and inflammatory cascade. PMID:23592614

  4. Glucose kinetics during prolonged exercise in highly trained human subjects: effect of glucose ingestion

    PubMed Central

    Jeukendrup, Asker E; Raben, Anne; Gijsen, Annemie; Stegen, Jos H C H; Brouns, Fred; Saris, Wim H M; Wagenmakers, Anton J M

    1999-01-01

    The objectives of this study were (1) to investigate whether glucose ingestion during prolonged exercise reduces whole body muscle glycogen oxidation, (2) to determine the extent to which glucose disappearing from the plasma is oxidized during exercise with and without carbohydrate ingestion and (3) to obtain an estimate of gluconeogenesis. After an overnight fast, six well-trained cyclists exercised on three occasions for 120 min on a bicycle ergometer at 50% maximum velocity of O2 uptake and ingested either water (Fast), or a 4% glucose solution (Lo-Glu) or a 22% glucose solution (Hi-Glu) during exercise. Dual tracer infusion of [U-13C]-glucose and [6,6-2H2]-glucose was given to measure the rate of appearance (Ra) of glucose, muscle glycogen oxidation, glucose carbon recycling, metabolic clearance rate (MCR) and non-oxidative disposal of glucose. Glucose ingestion markedly increased total Ra especially with Hi-Glu. After 120 min Ra and rate of disappearance (Rd) of glucose were 51-52 μmol kg−1 min−1 during Fast, 73-74 μmol kg−1 min−1 during Lo-Glu and 117–119 μmol kg−1 min−1 during Hi-Glu. The percentage of Rd oxidized was between 96 and 100% in all trials. Glycogen oxidation during exercise was not reduced by glucose ingestion. The vast majority of glucose disappearing from the plasma is oxidized and MCR increased markedly with glucose ingestion. Glucose carbon recycling was minimal suggesting that gluconeogenesis in these conditions is negligible. PMID:10050023

  5. The effect of carbohydrate ingestion on plasma interleukin-6, hepcidin and iron concentrations following prolonged exercise.

    PubMed

    Robson-Ansley, Paula; Walshe, Ian; Ward, Douglas

    2011-02-01

    The aim of our study was twofold, firstly to examine the relationship between plasma concentrations of IL-6, hepcidin and iron following prolonged exercise and secondly, to assess the effect of carbohydrate ingestion on circulating hepcidin concentration post-exercise. The study was a randomised double-blind cross-over design, with participants consuming either a carbohydrate (CHO) or an isovolumetric placebo drink throughout the trial. Nine healthy, trained males completed a treadmill run at 60% vVO(2max) for 120 min followed by a 5 km time trial. Plasma concentrations of both IL-6 and hepcidin significantly increased post-exercise following both trials (p<.05) and returned to baseline by 24 h post (p>.05). A positive correlation between hepcidin and IL-6 was demonstrated immediately following exercise during PLA while there was a trend for a moderate correlation during CHO (PLA trial rho=0.81, p<0.001; CHO trial rho=0.36, p=0.07). Plasma iron was unaffected immediately post-exercise but significantly reduced by 24 h post-exercise compared to baseline. CHO ingestion significantly reduced post-exercise IL-6 (p<.05) but this had no effect on plasma hepcidin or iron concentration. Our data demonstrate CHO supplementation does not alter the rapid hepcidin response associated with exercise and does not prevent a subsequent fall in plasma iron concentration. This finding adds further support to the theory that an exercise-induced, up-regulation of hepcidin activity is a mechanism causing iron deficiency in endurance athletes.

  6. The effect of prolonged ``bleaching'' on skeletal banding and stable isotopic composition in Montastrea annularis

    NASA Astrophysics Data System (ADS)

    Leder, James J.; Szmant, Alina M.; Swart, Peter K.

    1991-07-01

    X-radiography and carbon and oxygen stable isotope analysis have been used to examine the effects of prolonged “bleaching” on the growth rate and chemical composition of the skeleton of the massive reef coral, Montastrea annularis. The post-bleaching linear growth of one colony that remained bleached for 10 to 12 months following the 1987 Caribbean-wide bleaching event was only 37% of mean annual growth from pre-bleaching years, and was manifest as a loss of the following year's low density band. Two colonies that did not bleach (normal) and two that bleached and regained their coloration (recovered) had linear growth rates over the same period that were 81 to 98% of mean pre-bleaching annual growth. Linear growth by a third recovered coral was 66% of pre-bleaching growth. No sub-annual stress bands were associated with the bleaching. The skeleton of the bleached colony had carbon and oxygen isotopic compositions that were reduced in range and enriched (increased) in both 13C and 18O in the post-bleaching year. The skeletons of two of the nine colonies, one bleached and one recovered, had depleted (reduced) δ18O values (-5.3 and -4.8%., respectively) during the bleaching episode that agree with the suggestion that positive temperature anomalies occurred during, and may have caused, the bleaching event. The range and values for all other normal and recovered corals, however, were not different between the post-bleaching year and previous years. Our data suggest that stress bands and isotopic analysis of coral skeletons may not always be reliable tools for examining the occurrence, cause or effects of certain discrete stress events that may interrupt skeletal growth.

  7. Prolonged Minocycline Treatment Impairs Motor Neuronal Survival and Glial Function in Organotypic Rat Spinal Cord Cultures

    PubMed Central

    Pinkernelle, Josephine; Fansa, Hisham; Ebmeyer, Uwe; Keilhoff, Gerburg

    2013-01-01

    Background Minocycline, a second-generation tetracycline antibiotic, exhibits anti-inflammatory and neuroprotective effects in various experimental models of neurological diseases, such as stroke, Alzheimer’s disease, amyotrophic lateral sclerosis and spinal cord injury. However, conflicting results have prompted a debate regarding the beneficial effects of minocycline. Methods In this study, we analyzed minocycline treatment in organotypic spinal cord cultures of neonatal rats as a model of motor neuron survival and regeneration after injury. Minocycline was administered in 2 different concentrations (10 and 100 µM) at various time points in culture and fixed after 1 week. Results Prolonged minocycline administration decreased the survival of motor neurons in the organotypic cultures. This effect was strongly enhanced with higher concentrations of minocycline. High concentrations of minocycline reduced the number of DAPI-positive cell nuclei in organotypic cultures and simultaneously inhibited microglial activation. Astrocytes, which covered the surface of the control organotypic cultures, revealed a peripheral distribution after early minocycline treatment. Thus, we further analyzed the effects of 100 µM minocycline on the viability and migration ability of dispersed primary glial cell cultures. We found that minocycline reduced cell viability, delayed wound closure in a scratch migration assay and increased connexin 43 protein levels in these cultures. Conclusions The administration of high doses of minocycline was deleterious for motor neuron survival. In addition, it inhibited microglial activation and impaired glial viability and migration. These data suggest that especially high doses of minocycline might have undesired affects in treatment of spinal cord injury. Further experiments are required to determine the conditions for the safe clinical administration of minocycline in spinal cord injured patients. PMID:23967343

  8. Behavioral and electrophysiological taste responses change after brief or prolonged dietary sodium deprivation.

    PubMed

    Garcia, Joanne M; Curtis, Kathleen S; Contreras, Robert J

    2008-12-01

    Dietary Na+ deprivation elicits a hormonal response to promote sodium conservation and a behavioral response to increase sodium ingestion. It has generally been accepted that the former occurs within 24 h after sodium deprivation, while the latter is delayed and may not appear until as much as 10 days later. Na+ deprivation of similar duration also decreases the sensitivity of the chorda tympani nerve (CT) to NaCl, suggesting that changes in CT responses are necessary for increased NaCl intake. However, previous work from our laboratory showed that licking responses to NaCl solutions increase after only 2 days of Na+ deprivation, suggesting rapidly occurring changes in response to NaCl taste. The present experiments examined the effects of 2 days of dietary Na+ deprivation on CT responses to NaCl and patterns of NaCl consumption and found that Na+-deficient rats licked significantly more during the first NaCl intake bout compared with control rats. CT responses to NaCl were reduced at all concentrations after brief Na+ deprivation compared with Na+-replete control rats and did not decrease further with prolonged (10 days) dietary Na+ deficiency. Moreover, amiloride, which suppressed CT responses to NaCl by approximately 30% in control rats, had virtually no effect on CT responses in Na+-deprived rats. Thus, 2 days of Na+ deprivation is sufficient to alter patterns of ingestion of concentrated NaCl and to reduce gustatory responses to NaCl. Furthermore, changes in gustatory responses to NaCl during dietary Na+ deprivation may involve the amiloride-sensitive component of the CT.

  9. Thermal buffering of concrete by seaweeds during a prolonged summer heatwave

    NASA Astrophysics Data System (ADS)

    Naylor, Larissa; Coombes, Martin

    2014-05-01

    Hard coastal infrastructure is subject to aggressive environmental conditions, including a suite of weathering processes in the intertidal zone. These processes, along with waves, lead to costly deterioration of coastal structures. Existing methods (e.g. coatings, less porous concrete) to reduce the risk of concrete deterioration rapidly lose their effectiveness in the intertidal zone. Additionally, a changing climate will lead to increased frequency of storms, higher sea level and higher extreme temperatures - and therefore, pose an increased risk of deterioration. Might there be a biogenic solution? New research (Coombes et al. 2013) has shown that fucoid seaweeds reduce microclimatic extremes and variability under normal summer conditions. The results presented here supplement these findings in two ways. First, they demonstrate that fucoid seaweeds act as a thermal buffer during a prolonged summer heatwave in Britain (July 2013). Over 36 days of continuous monitoring at two sites in Cornwall, UK, 19 of which were during the official heatwave, there were statistically significant differences (p = 0.000) in the maximum temperatures between thick seaweed (7.5 - 9.5 cm thickness) and thin seaweed (2 - 2.5 cm thickness) plots. Maximum temperatures reached 22°C and 33°C, for thick seaweed and thin seaweed plots, respectively. Variations in maximum temperatures between the two sites appear to be related to aspect. Second, the significantly different maximum temperature results between plots also demonstrate that seaweed thickness is an important factor influencing thermal buffering capacity. These data clearly demonstrate that fucoid seaweeds buffer concrete seawalls against extreme temperature fluxes during a heatwave, probably limiting the efficiency of deteriorative processes such as thermal expansion and contraction and salt crystallisation.

  10. Effects of prolonged moderate body deuteration on proliferative activity in major cell renewal systems in mice

    SciTech Connect

    Hodel, A.; Gebbers, J.-O.; Cottier, H.; Laissue, J.A.

    1982-06-07

    To evaluate the effects of prolonged moderate body deuteration on incorporation of tritiated thymidine (/sup 3/HTdR) into the DNA of major cell renewal systems, young adult mice were given drinking fluid containing 30 % heavy water for 7, 14, 21, 42 and 70 days. Control mice drank tap water. Three hours prior to sacrifice, 925 kBq of HTdR were injected intravenously. Following extraction of the bulk of the soluble activity with an aqueous formalin solution, the residual /sup 3/H-activity of the organs was assayed by liquid scintillation counting and by autoradiography. The total thymic /sup 3/H-activity and the thymic weight, particularly of the cortex, were significantly reduced indeuterated mice early in the course of the experiment. The fraction of labeled thymocytes diminished to less than one half of the control values on day 70. The /sup 3/H-activity of the bone marrow in deuterated mice was reduced to about 3.4 of control values. In contrast, the total /sup 3/H-activity of the small intestine, as well as mean labeling index and mitotic index of small intestinal epithelia, were mot markedly altered in deuterated versus control mice. Drinking water containing 30 % of heavy water did thus not result in generalized, profound and progressive disturbance of HTdR incorporation in all the major cell renewal systems in the mouse. The thymus and, to a lesser extent, the bone marrow, were unquestionably affected, but the depression of HTdR incorporation did not increase markedly in the course of 10 weeks. In these terms, the toxicity of 30 % heavy wateer in the drinking fluid appears minor. This is of particular interest since exposure to similar concentrations is known to elicit immunodepressive and/or antineoplastic effects.

  11. Some features of the bioelectric activity of the muscles with prolonged hypokinesia

    NASA Technical Reports Server (NTRS)

    Belaya, N. A.; Amirov, R. Z.; Shaposhnikov, Y. A.; Lebedeva, I. P.; Sologub, B. S.

    1978-01-01

    The effects of prolonged hypokinesia, brought on by confinement to bed and the attendant lack of motor activity, on the bioelectric activity of muscles are studied. Electromyographic measurements of amplitude and frequency indicators of muscular bioelectric activity were analyzed.

  12. The Effect of Ethanol on the Release of Opioids from Oral Prolonged-Release Preparations

    PubMed Central

    Walden, Malcolm; Nicholls, Fiona A.; Smith, Kevin J.; Tucker, Geoffrey T.

    2007-01-01

    Recent experience has prompted the US FDA to consider whether ethanol ingestion may modify the release characteristics of prolonged-release formulations, where dose dumping may be an issue for patient safety. The influence of ethanol on the in vitro release of opioid drugs from some prolonged-release formulations utilizing different release technologies was examined. Results indicated that the prolonged-release mechanisms remained intact under the testing conditions, although one product showed initial sensitivity to ethanol in its release characteristics. Nevertheless, in this case, extrapolation of the findings to likely outcome in vivo indicated no risk of dose-dumping. It is proposed that prolonged-release medicinal products should be tested during development to ensure robustness to the effects of ethanol on drug release. PMID:17882730

  13. The Mind-Body Connection - Can Prolonged Stress Affect Whether Breast Cancer Returns?

    MedlinePlus

    ... Past Issues The Mind-Body Connection Can Prolonged Stress Affect Whether Breast Cancer Returns? Past Issues / Winter ... traumatic life events. The categories ranged from traumatic stress to some stress to no significant stress. According ...

  14. Underutilization of Mental Health Services Among Bereaved Caregivers With Prolonged Grief Disorder

    PubMed Central

    Lichtenthal, Wendy G.; Nilsson, Matthew; Kissane, David W.; Breitbart, William; Kacel, Elizabeth; Jones, Eric C.; Prigerson, Holly G.

    2013-01-01

    Objective This study examined grief and mental health service use among 86 bereaved caregivers of advanced cancer patients. Methods Caregivers were assessed before (median=3.1 months) and after (median=6.6 months) patients’ deaths for prolonged grief disorder, axis I psychiatric disorders, mental health service use, suicidality, and health-related quality of life. Results Sixteen percent of the bereaved sample met criteria for prolonged grief disorder, which was significantly associated with suicidality and poorer health-related quality of life, but not with mental health service use. The majority of bereaved caregivers with prolonged grief disorder did not access mental health services. In multivariable analyses, having discussed psychological concerns with a health care professional when the patient was ill was the only significant predictor of mental health service use during bereavement. Conclusions Because bereaved caregivers with prolonged grief disorder underutilize mental health services, connecting them with services while the patient is still alive may be beneficial. PMID:21969652

  15. Prolonged oculogyric crisis on addition of nifedipine to neuroleptic medication regime.

    PubMed

    Singh, I

    1987-01-01

    Extrapyramidal symptoms, including oculogyric crisis, are well recognised side-effects of clopenthixol medication, but precipitation of prolonged oculogyric crisis on addition of nifedipine to an ongoing clopenthixol regime has not so far been reported.

  16. Resuscitation of prolonged cardiac arrest from massive pulmonary embolism by extracorporeal membrane oxygenation.

    PubMed

    Kim, Yun Seok; Choi, Wookjin; Hwang, Jaecheol

    2017-01-10

    Extracorporeal cardiopulmonary resuscitation can be used as a rescue strategy in cases of prolonged cardiac arrest caused by massive pulmonary embolism. We present a case of a male patient who was in prolonged cardiac arrest following massive pulmonary embolism. Veno-arterial extracorporeal membrane oxygenation was initiated approximately 93 min after prolonged cardiopulmonary resuscitation. After resuscitation, bedside echocardiography and a chest computed tomography angiogram revealed a massive pulmonary embolism during extracorporeal membrane oxygenation support. The patient received transcatheter mechanical thrombectomy without haemodynamic instability in extracorporeal membrane oxygenation support. He was also treated with therapeutic hypothermia to improve neurological outcome. Renal replacement therapy for acute kidney injury was continued for 36 days. The patient was discharged at 60 days after admission with no serious complications. This case demonstrates that veno-arterial extracorporeal membrane oxygenation and therapeutic hypothermia are an effective treatment strategy for prolonged cardiac arrest caused by massive pulmonary embolism.

  17. The role of microglial mtDNA damage in age-dependent prolonged LPS-induced sickness behavior.

    PubMed

    Nakanishi, Hiroshi; Hayashi, Yoshinori; Wu, Zhou

    2011-02-01

    Microglia are the main cellular source of oxidation products and inflammatory molecules in the brain during aging. The accumulation of mitochondrial DNA (mtDNA) oxidative damage in microglia during aging results in the increased production of reactive oxygen species (ROS). The increased intracellular ROS, in turn, activates a redox-sensitive nuclear factor-κB (NF-κB) to provoke excessive neuroinflammation, resulting in memory deficits and the prolonged behavioral consequence of infection. Besides its role in regulating the gene copy number, mitochondrial transcription factor A (TFAM) is closely associated with the stabilization of mtDNA structures. Lipopolysaccharide (LPS) induces the generation of ROS from the actively respirating mitochondria as well as NADPH oxidase, and leads to the subsequent activation of the NF-κB-dependent inflammatory pathway in aging microglia. The overexpression of human TFAM improves the age-dependent prolonged LPS-induced sickness behaviors by ameliorating the mtDNA damage and reducing the resultant redox-regulated inflammatory responses. Therefore, 'microglia-aging' plays important roles in the age-dependent enhanced behavioral consequences of infection.

  18. Prolonged activity of a recombinant factor VIII-Fc fusion protein in hemophilia A mice and dogs

    PubMed Central

    Dumont, Jennifer A.; Liu, Tongyao; Low, Susan C.; Zhang, Xin; Kamphaus, George; Sakorafas, Paul; Fraley, Cara; Drager, Douglas; Reidy, Thomas; McCue, Justin; Franck, Helen W. G.; Merricks, Elizabeth P.; Nichols, Timothy C.; Bitonti, Alan J.; Pierce, Glenn F.

    2012-01-01

    Despite proven benefits, prophylactic treatment for hemophilia A is hampered by the short half-life of factor VIII. A recombinant factor VIII-Fc fusion protein (rFVIIIFc) was constructed to determine the potential for reduced frequency of dosing. rFVIIIFc has an ∼ 2-fold longer half-life than rFVIII in hemophilia A (HemA) mice and dogs. The extension of rFVIIIFc half-life requires interaction of Fc with the neonatal Fc receptor (FcRn). In FcRn knockout mice, the extension of rFVIIIFc half-life is abrogated, and is restored in human FcRn transgenic mice. The Fc fusion has no impact on FVIII-specific activity. rFVIIIFc has comparable acute efficacy as rFVIII in treating tail clip injury in HemA mice, and fully corrects whole blood clotting time (WBCT) in HemA dogs immediately after dosing. Furthermore, consistent with prolonged half-life, rFVIIIFc shows 2-fold longer prophylactic efficacy in protecting HemA mice from tail vein transection bleeding induced 24-48 hours after dosing. In HemA dogs, rFVIIIFc also sustains partial correction of WBCT 1.5- to 2-fold longer than rFVIII. rFVIIIFc was well tolerated in both species. Thus, the rescue of FVIII by Fc fusion to provide prolonged protection presents a novel pathway for FVIII catabolism, and warrants further investigation. PMID:22246033

  19. Prolonged exposure and virtual reality-enhanced imaginal exposure for PTSD following a terrorist bulldozer attack: a case study.

    PubMed

    Freedman, Sara A; Hoffman, Hunter G; Garcia-Palacios, Azucena; Tamar Weiss, Patrice L; Avitzour, Sara; Josman, Naomi

    2010-02-01

    In this case study, virtual reality was used to augment imaginal exposure in a protocol based on prolonged exposure. A 29-year-old male patient developed posttraumatic stress disorder after surviving a deadly terrorist bulldozer attack on two civilian buses and several cars in Jerusalem; the traumas witnessed by the survivor included a decapitation. The crowded bus in which the patient was riding was pushed over onto its side by the terrorist, injuring, trapping, and terrifying the passengers and causing gasoline to leak. Guided by his therapist, the patient entered an immersive computer-generated virtual world to go "back" to the scene of the traumatic event to help him gain access to his memories of the event, process and reduce the intensity of the emotions (fear/anger) associated with his pathological memories, and change unhealthy thought patterns. Traumatic memories of childhood abuse and traumatic memories of the bulldozer terrorist attack were treated using imaginal exposure while the patient was in the virtual environment BusWorld. The patient showed large posttreatment reductions in PTSD symptoms, and his Clinician-Administered PTSD Scale (CAPS) scores dropped from 79 pretreatment to zero immediately posttreatment, and CAPS was still at zero 6 months later. Although case studies are inconclusive by nature, these encouraging preliminary results suggest that further exploration of the use of virtual reality during modified prolonged exposure for PTSD is warranted. As terrorist attacks increase in frequency and severity worldwide, research is needed on how to minimize the psychological consequences of terrorism.

  20. Candida endophthalmitis: an unusual complication of prolonged intravenous access

    PubMed Central

    Vose, M; Beatty, S; Charles, S

    2001-01-01

    A 16 year old boy awaiting a defunctioning colostomy for Crohn's disease complained of reduced vision in his left eye. Four weeks previously candida had been isolated from his central line used for parenteral feeds. Fundal examination of the left eye revealed a macular abscess with a classic "string of pearls" appearance of multiple vitreous abscesses. This was treated with pars plana vitrectomy and intravitreal antifungal therapy. Microbiological studies confirmed a diagnosis of candida endophthalmitis.


Keywords: candida; endophthalmitis; intravitreal PMID:11161082

  1. Subtleties in practical application of prolonged infusion of β-lactam antibiotics.

    PubMed

    De Waele, Jan J; Lipman, Jeffrey; Carlier, Mieke; Roberts, Jason A

    2015-05-01

    Prolonged infusion (PI) of β-lactam antibiotics is increasingly used in order to optimise antibiotic exposure in critically ill patients. Physicians are often not aware of a number of subtleties that may jeopardise the treatment. In this clinically based paper, we stress pragmatic issues, such as the importance of a loading dose before PI, and discuss a number of important practicalities that are mandatory to benefit from the pharmacokinetic advantages of prolonged β-lactam antibiotic administration.

  2. Metronidazole-induced encephalopathy after prolonged metronidazole course for treatment of C. difficile colitis

    PubMed Central

    Godfrey, Mark S; Finn, Arkadiy; Zainah, Hadeel; Dapaah-Afriyie, Kwame

    2015-01-01

    A 65-year-old woman with a diagnosis of Clostridium difficile colitis undergoing prolonged treatment with metronidazole was admitted to hospital for altered mentation, slurred speech and weakness. She was diagnosed with metronidazole-induced encephalopathy, confirmed with brain MRI and improved when the offending agent was removed. This case report highlights encephalopathy as a complication of prolonged metronidazole treatment, which has become more common in clinical practice for the treatment of C. difficile infection. PMID:25596288

  3. Prolongation anormale d'un bloc fémoral analgésique: cas Clinique

    PubMed Central

    Koné, Joseph; Bensghir, Mustapha; Boutayeb, El Houcine; Haimeur, Charki

    2015-01-01

    La prolongation anormale d'un bloc nerveux peut être définie comme un dépassement du délai habituel de récupération sensitive ou motrice. A travers un cas clinique d'une prolongation anormale d'un bloc analgésique et une revue de la littérature, les auteurs discutent les facteurs de risque et les moyens de prévention de cette complication. PMID:26918085

  4. Implementation of Prolonged Exposure in the Army: Is Consultation Necessary for Effective Dissemination

    DTIC Science & Technology

    2015-10-01

    in posttraumatic stress disorder . Journal of Nervous and Mental Disease, 201(8), 691-697. Foa, E. B., Hembree, E. A., Cahill, S. P., Rauch, S. A...M., Riggs, D. S., Feeny, N. C., & Yadin, E. (2005). Randomized trial of prolonged exposure for posttraumatic stress disorder with and without...dialectical behavior therapy prolonged exposure protocol for suicidal and self-injuring women with borderline personality disorder and PTSD

  5. Metronidazole-induced encephalopathy after prolonged metronidazole course for treatment of C. difficile colitis.

    PubMed

    Godfrey, Mark S; Finn, Arkadiy; Zainah, Hadeel; Dapaah-Afriyie, Kwame

    2015-01-16

    A 65-year-old woman with a diagnosis of Clostridium difficile colitis undergoing prolonged treatment with metronidazole was admitted to hospital for altered mentation, slurred speech and weakness. She was diagnosed with metronidazole-induced encephalopathy, confirmed with brain MRI and improved when the offending agent was removed. This case report highlights encephalopathy as a complication of prolonged metronidazole treatment, which has become more common in clinical practice for the treatment of C. difficile infection.

  6. Prolonging thermal barrier coated specimen life by thermal cycle management

    NASA Technical Reports Server (NTRS)

    Hendricks, R. C.; Mcdonald, G.; Poolos, N. P.

    1981-01-01

    Thermal barrier coatings applied to the heated side of engine components such as seals, combustor, and blades of a gas turbine offer a potential increase in efficiency through the use of higher gas temperatures or less cooling air or benefits arising from extended component life by reducing component metal temperatures. The considered investigation has the objective to show that while a thermal barrier coated (TBC) specimen can be brought to a fixed temperature using various fuel-air ratio (F/A) values, lower calculated stresses are associated with lower (F/A) values. This implies that control of (F/A) values (i.e., rates of heat input) during the starting transient and to a lesser extent during shutdown and operation, offers a potential method of improving TBC lifetime through thermal cycle management.

  7. The role of internal variability in prolonging the California drought

    NASA Astrophysics Data System (ADS)

    Buenning, N. H.; Stott, L. D.

    2015-12-01

    The current drought in California has been one of the driest on record. Using atmospheric general circulation models (AGCMs), recent studies have demonstrated that the low precipitation anomalies observed during the first three winters of the current drought are mostly attributable to changes in sea surface temperature (SST) and sea ice forcing. Here we show through AGCM simulations that the fourth and latest winter of the current drought is not attributable to SST and sea ice forcing, but instead a consequence of higher internal variability. Using the Global Spectral Model (GSM) we demonstrate how the surface forcing reproduces dry conditions over California for the first three winters of the current drought, similar to what other models produced. However, when forced with the SST and sea ice conditions for the winter of 2014-2015, GSM robustly simulates high precipitation conditions over California. This significantly differs with observed precipitation anomalies, which suggests a model deficiency or large influence of internal variability within the climate system during the winter of 2014-2015. Ensemble simulations with 234 realizations reveal that the surface forcing created a broader range of precipitation possibilities over California. Thus, the surface forcing caused a greater degree of internal variations, which was driven by a reduced latitudinal temperature gradient and amplified planetary waves over the Pacific. Similar amplified waves are also seen in 21st century climate projections of upper-level geopotential heights, suggesting that 21st century precipitation over California will become more variable and increasingly difficult to predict on seasonal timescales. When an El Nino pattern is applied to the surface forcing the precipitation further increases and the variance amongst model realizations is reduced, which indicates a strong likelihood of an anomalously wet 2015-2016 winter season.

  8. Influence of Sex on Microvascular and Macrovascular Responses to Prolonged Sitting.

    PubMed

    Vranish, Jennifer R; Young, Benjamin E; Kaur, Jasdeep; Patik, Jordan C; Padilla, Jaume; Fadel, Paul J

    2017-01-27

    Increased daily sitting time is associated with greater cardiovascular risk, and on average women are more sedentary than men. Recent reports have demonstrated that prolonged sitting reduces lower leg microvascular (reactive hyperemia) and macrovascular (flow-mediated dilation, FMD) vasodilator function. However, these studies have predominately included men, and the effects of sitting in young women are largely unexplored. This becomes important given known sex differences in vascular function. Thus herein, we assessed popliteal artery reactive hyperemia and FMD, before and after a 3hr sitting period, in healthy young women (n=12) and men (n=8). In addition, resting popliteal artery hemodynamics (duplex Doppler ultrasound), and calf circumference were measured before, during, and after sitting. Resting popliteal artery shear rate was reduced to a similar extent in both groups during the sitting period (women: -48.5±8.4s(-1), men: -52.9±12.3s(-1); P=0.45). This was accompanied by comparable increases in calf circumference in men and women (P=0.37). Following the sitting period, popliteal artery FMD was significantly reduced in men (PreSIT: 5.5±0.9%, PostSIT: 1.6±0.4%; P<0.001) but not women (PreSIT: 4.4±0.6%, PostSIT: 3.6±0.6%; P=0.29). In contrast, both groups demonstrated similar reductions in hyperemic blood flow AUC (women: -28,860±5,742 a.u., men: -28,691±9,685 a.u.; P=0.99) indicating impaired microvascular reactivity after sitting. These findings indicate that despite comparable reductions in shear rate during 3 hours of uninterrupted sitting, macrovascular function appears protected in some young women but the response was variable, whereas men exhibited more consistent reductions in FMD. In contrast, the leg microvasculature is susceptible to similar sitting-induced impairments in men and women.

  9. Importance of internal hydraulic redistribution for prolonging the lifespan of roots in dry soil.

    PubMed

    Bauerle, T L; Richards, J H; Smart, D R; Eissenstat, D M

    2008-02-01

    Redistribution of water within plants could mitigate drought stress of roots in zones of low soil moisture. Plant internal redistribution of water from regions of high soil moisture to roots in dry soil occurs during periods of low evaporative demand. Using minirhizotrons, we observed similar lifespans of roots in wet and dry soil for the grapevine 'Merlot' (Vitis vinifera) on the rootstock 101-14 Millardet de Gramanet (Vitis riparia x Vitis rupestris) in a Napa County, California vineyard. We hypothesized that hydraulic redistribution would prevent an appreciable reduction in root water potential and would contribute to prolonged root survivorship in dry soil zones. In a greenhouse study that tested this hypothesis, grapevine root systems were divided using split pots and were grown for 6 months. With thermocouple psychrometers, we measured water potentials of roots of the same plant in both wet and dry soil under three treatments: control (C), 24 h light + supplemental water (LW) and 24 h light only (L). Similar to the field results, roots in the dry side of split pots had similar survivorship as roots in the wet side of the split pots (P = 0.136) in the C treatment. In contrast, reduced root survivorship was directly associated with plants in which hydraulic redistribution was experimentally reduced by 24 h light. Dry-side roots of plants in the LW treatment lived half as long as the roots in the wet soil despite being provided with supplemental water (P < 0.0004). Additionally, pre-dawn water potentials of roots in dry soil under 24 h of illumination (L and LW) exhibited values nearly twice as negative as those of C plants (P = 0.034). Estimates of root membrane integrity using electrolyte leakage were consistent with patterns of root survivorship. Plants in which nocturnal hydraulic redistribution was reduced exhibited more than twice the amount of electrolyte leakage in dry roots compared to those in wet soil of the same plant. Our study demonstrates that

  10. Prolonged cytotoxic effect of colchicine released from biodegradable microspheres.

    PubMed

    Muvaffak, Asli; Gurhan, Ismet; Hasirci, Nesrin

    2004-11-15

    One the main problems of cancer chemotherapy is the unwanted damage to normal cells caused by the high toxicities of anticancer drugs. Any system of controlled drug delivery that would reduce the total amount of drug required, and thus reduce the side effects, would potentially help to improve chemotherapy. In this respect, biodegradable gelatin microspheres were prepared by water/oil emulsion polymerization and by crosslinking with glutaraldehyde (GTA) as the drug-carrier system. Microspheres were loaded with colchicine, a model antimitotic drug, which was frequently used as an antimitotic agent in cancer research involving cell cultures. Microsphere sizes, swelling and degradation properties, drug-release kinetics, and cytotoxities were studied. Swelling characteristics of microspheres changed upon changing GTA concentration. A decrease in swelling values was recorded as GTA crosslink density was increased. In vitro drug release in PBS (0.01M, pH 7.4) showed rapid colchicine release up to approximately 83% (at t = 92 h) for microspheres with low GTA (0.05% v/v), whereas a slower release profile (only approximately 39%) was obtained for microspheres with high GTA (0.50% v/v) content, for the same period. Cytotoxicity tests with MCF-7, HeLa and H-82 cancer cell lines showed that free colchicine was very toxic, showing an approximately 100% lethal effect in both HeLa and H-82 cell lines and more than 50% decrease in viability in MCF-7 cells in 4 days. Indeed, entrapped colchicine indicated similar initial high toxic effect on cell viability in MCF-7 cell line and this effect became more dominant as colchicine continued to be released from microspheres in the same period. In conclusion, the control of the release rate of colchicine from gelatin microspheres was achieved under in vitro conditions by gelatin through the alteration of crosslinking conditions. Indeed, the results suggested the potential application of gelatin microspheres crosslinked with GTA as a

  11. Coscinaraea marshae corals that have survived prolonged bleaching exhibit signs of increased heterotrophic feeding

    NASA Astrophysics Data System (ADS)

    Bessell-Browne, Pia; Stat, Michael; Thomson, Damian; Clode, Peta L.

    2014-09-01

    Colonies of Coscinaraea marshae corals from Rottnest Island, Western Australia have survived for more than 11 months in various bleached states following a severe heating event in the austral summer of 2011. These colonies are situated in a high-latitude, mesophotic environment, which has made their long-term survival of particular interest as such environments typically suffer from minimal thermal pressures. We have investigated corals that remain unbleached, moderately bleached, or severely bleached to better understand potential survival mechanisms utilised in response to thermal stress. Specifically, Symbiodinium (algal symbiont) density and genotype, chlorophyll- a concentrations, and δ13C and δ15N levels were compared between colonies in the three bleaching categories. Severely bleached colonies housed significantly fewer Symbiodinium cells ( p < 0.05) and significantly reduced chlorophyll- a concentrations ( p < 0.05), compared with unbleached colonies. Novel Symbiodinium clade associations were observed for this coral in both severely and moderately bleached colonies, with clade C and a mixed clade population detected. In unbleached colonies, only clade B was observed. Levels of δ15N indicate that severely bleached colonies are utilising heterotrophic feeding mechanisms to aid survival whilst bleached. Collectively, these results suggest that these C. marshae colonies can survive with low symbiont and chlorophyll densities, in response to prolonged thermal stress and extended bleaching, and increase heterotrophic feeding levels sufficiently to meet energy demands, thus enabling some colonies to survive and recover over long time frames. This is significant as it suggests that corals in mesophotic and high-latitude environments may possess considerable plasticity and an ability to tolerate and adapt to large environmental fluctuations, thereby improving their chances of survival as climate change impacts coral ecosystems worldwide.

  12. Prolonged Glucocorticoid Treatment in ARDS: Impact on Intensive Care Unit-Acquired Weakness

    PubMed Central

    Meduri, Gianfranco Umberto; Schwingshackl, Andreas; Hermans, Greet

    2016-01-01

    Systemic inflammation and duration of immobilization are strong independent risk factors for the development of intensive care unit-acquired weakness (ICUAW). Activation of the pro-inflammatory transcription factor nuclear factor-κB (NF-κB) results in muscle wasting during disuse-induced skeletal muscle atrophy (ICU bed rest) and septic shock. In addition, NF-κB-mediated signaling plays a significant role in mechanical ventilation-induced diaphragmatic atrophy and contractile dysfunction. Older trials investigating high dose glucocorticoid treatment reported a lack of a sustained anti-inflammatory effects and an association with ICUAW. However, prolonged low-to-moderate dose glucocorticoid treatment of sepsis and ARDS is associated with a reduction in NF-κB DNA-binding, decreased transcription of inflammatory cytokines, enhanced resolution of systemic and pulmonary inflammation, leading to fewer days of mechanical ventilation, and lower mortality. Importantly, meta-analyses of a large number of randomized controlled trials investigating low-to-moderate glucocorticoid treatment in severe sepsis and ARDS found no increase in ICUAW. Furthermore, while the ARDS network trial investigating methylprednisolone treatment in persistent ARDS is frequently cited to support an association with ICUAW, a reanalysis of the data showed a similar incidence with the control group. Our review concludes that in patients with sepsis and ARDS, any potential direct harmful neuromuscular effect of glucocorticoids appears outweighed by the overall clinical improvement and reduced duration of organ failure, in particular ventilator dependency and associated immobilization, which are key risk factors for ICUAW. PMID:27532030

  13. Prolonged self-paced exercise in the heat – environmental factors affecting performance

    PubMed Central

    Junge, Nicklas; Jørgensen, Rasmus; Flouris, Andreas D.; Nybo, Lars

    2016-01-01

    ABSTRACT In this review we examine how self-paced performance is affected by environmental heat stress factors during cycling time trial performance as well as considering the effects of exercise mode and heat acclimatization. Mean power output during prolonged cycling time trials in the heat (≥30°C) was on average reduced by 15% in the 14 studies that fulfilled the inclusion criteria. Ambient temperature per se was a poor predictor of the integrated environmental heat stress and 2 of the prevailing heat stress indices (WBGT and UTCI) failed to predict the environmental influence on performance. The weighing of wind speed appears to be too low for predicting the effect for cycling in trained acclimatized subjects, where performance may be maintained in outdoor time trials at ambient temperatures as high as 36°C (36°C UTCI; 28°C WBGT). Power output during indoor trials may also be maintained with temperatures up to at least 27°C when humidity is modest and wind speed matches the movement speed generated during outdoor cycling, whereas marked reductions are observed when air movement is minimal. For running, representing an exercise mode with lower movement speed and higher heat production for a given metabolic rate, it appears that endurance is affected even at much lower ambient temperatures. On this basis we conclude that environmental heat stress impacts self-paced endurance performance. However, the effect is markedly modified by acclimatization status and exercise mode, as the wind generated by the exercise (movement speed) or the environment (natural or fan air movement) exerts a strong influence. PMID:28090557

  14. Impact of prolonged leucine supplementation on protein synthesis and lean growth in neonatal pigs.

    PubMed

    Columbus, Daniel A; Steinhoff-Wagner, Julia; Suryawan, Agus; Nguyen, Hanh V; Hernandez-Garcia, Adriana; Fiorotto, Marta L; Davis, Teresa A

    2015-09-15

    Most low-birth weight infants experience extrauterine growth failure due to reduced nutrient intake as a result of feeding intolerance. The objective of this study was to determine whether prolonged enteral leucine supplementation improves lean growth in neonatal pigs fed a restricted protein diet. Neonatal pigs (n = 14-16/diet, 5 days old, 1.8 ± 0.3 kg) were fed by gastric catheter a whey-based milk replacement diet with either a high protein (HP) or restricted protein (RP) content or RP supplemented with leucine to the same level as in the HP diet (RPL). Pigs were fed 40 ml·kg body wt(-1)·meal(-1) every 4 h for 21 days. Feeding the HP diet resulted in greater total body weight and lean body mass compared with RP-fed pigs (P < 0.05). Masses of the longissimus dorsi muscle, heart, and kidneys were greater in the HP- than RP-fed pigs (P < 0.05). Body weight, lean body mass, and masses of the longissimus dorsi, heart, and kidneys in pigs fed the RPL diet were intermediate to RP- and HP-fed pigs. Protein synthesis and mTOR signaling were increased in all muscles with feeding (P < 0.05); leucine supplementation increased mTOR signaling and protein synthesis rate in the longissimus dorsi (P < 0.05). There was no effect of diet on indices of protein degradation signaling in any tissue (P > 0.05). Thus, when protein intake is chronically restricted, the capacity for leucine supplementation to enhance muscle protein accretion in neonatal pigs that are meal-fed milk protein-based diets is limited.

  15. Body Fineness Ratio as a Predictor of Maximum Prolonged-Swimming Speed in Coral Reef Fishes

    PubMed Central

    Walker, Jeffrey A.; Alfaro, Michael E.; Noble, Mae M.; Fulton, Christopher J.

    2013-01-01

    The ability to sustain high swimming speeds is believed to be an important factor affecting resource acquisition in fishes. While we have gained insights into how fin morphology and motion influences swimming performance in coral reef fishes, the role of other traits, such as body shape, remains poorly understood. We explore the ability of two mechanistic models of the causal relationship between body fineness ratio and endurance swimming-performance to predict maximum prolonged-swimming speed (Umax) among 84 fish species from the Great Barrier Reef, Australia. A drag model, based on semi-empirical data on the drag of rigid, submerged bodies of revolution, was applied to species that employ pectoral-fin propulsion with a rigid body at Umax. An alternative model, based on the results of computer simulations of optimal shape in self-propelled undulating bodies, was applied to the species that swim by body-caudal-fin propulsion at Umax. For pectoral-fin swimmers, Umax increased with fineness, and the rate of increase decreased with fineness, as predicted by the drag model. While the mechanistic and statistical models of the relationship between fineness and Umax were very similar, the mechanistic (and statistical) model explained only a small fraction of the variance in Umax. For body-caudal-fin swimmers, we found a non-linear relationship between fineness and Umax, which was largely negative over most of the range of fineness. This pattern fails to support either predictions from the computational models or standard functional interpretations of body shape variation in fishes. Our results suggest that the widespread hypothesis that a more optimal fineness increases endurance-swimming performance via reduced drag should be limited to fishes that swim with rigid bodies. PMID:24204575

  16. Spatial properties of the prolonged depolarizing afterpotential in barnacle photoreceptors. I. The induction process

    SciTech Connect

    Almagor, E.; Hillman, P.; Minke, B.

    1986-03-01

    In invertebrate photoreceptors, when the light stimulus results in substantial net transfer of the visual pigment from the rhodopsin (R) to the metarhodopsin (M) state, the ordinary late receptor potential (LRP) is followed by a prolonged depolarizing afterpotential (PDA). The dependence of the amplitude of the PDA on the amount of pigment conversion is strongly supralinear, and the PDA duration also depends on this amount. These observations indicate an interaction among the elements of the PDA induction process and also make possible a test of the range of this interaction. The test consists of a comparison of the PDA after localized pigment conversion, obtained by strong spot illumination, to that after weaker diffuse illumination converting a comparable total amount of pigment. The experiment was performed on the barnacle lateral eye. The effective spot size was measured by the early receptor potential (ERP), in seawater saturated with CO/sub 2/, which considerably reduced the electrical coupling between the photoreceptors. The ERP was also used to determine whether there is diffusion of R molecules into the illuminated spot. The spot illumination induced a PDA with small amplitude and long duration, while no detectable PDA was induced by the diffuse light. This indicates that the range of the PDA interaction is much smaller than the entire cell. In addition, the ERP results showed that there was no detectable diffusion of R molecules into the illuminated spot area over 30 min. This measurement, with a calculated correction for the microvillar geometry of the photoreceptor, enabled us to put an upper limit on the diffusion coefficient of the pigment molecules in the inact, unfixed barnacle photoreceptor of D less than 6 X 10(-9) cm2 s-1.

  17. Prolonged Sitting is Associated with Attenuated Heart Rate Variability during Sleep in Blue-Collar Workers.

    PubMed

    Hallman, David M; Sato, Tatiana; Kristiansen, Jesper; Gupta, Nidhi; Skotte, Jørgen; Holtermann, Andreas

    2015-11-19

    Prolonged sitting is associated with increased risk for cardiovascular diseases and mortality. However, research into the physiological determinants underlying this relationship is still in its infancy. The aim of the study was to determine the extent to which occupational and leisure-time sitting are associated with nocturnal heart rate variability (HRV) in blue-collar workers. The study included 138 blue-collar workers (mean age 45.5 (SD 9.4) years). Sitting-time was measured objectively for four days using tri-axial accelerometers (Actigraph GT3X+) worn on the thigh and trunk. During the same period, a heart rate monitor (Actiheart) was used to sample R-R intervals from the electrocardiogram. Time and frequency domain indices of HRV were only derived during nighttime sleep, and used as markers of cardiac autonomic modulation. Regression analyses with multiple adjustments (age, gender, body mass index, smoking, job-seniority, physical work-load, influence at work, and moderate-to-vigorous physical activity) were used to investigate the association between sitting time and nocturnal HRV. We found that occupational sitting-time was negatively associated (p < 0.05) with time and frequency domain HRV indices. Sitting-time explained up to 6% of the variance in HRV, independent of the covariates. Leisure-time sitting was not significantly associated with any HRV indices (p > 0.05). In conclusion, objectively measured occupational sitting-time was associated with reduced nocturnal HRV in blue-collar workers. This indicates an attenuated cardiac autonomic regulation with increasing sitting-time at work regardless of moderate-to-vigorous physical activity. The implications of this association for cardiovascular disease risk warrant further investigation via long-term prospective studies and intervention studies.

  18. Spatial properties of the prolonged depolarizing afterpotential in barnacle photoreceptors. I. The induction process

    PubMed Central

    1986-01-01

    In invertebrate photoreceptors, when the light stimulus results in substantial net transfer of the visual pigment from the rhodopsin (R) to the metarhodopsin (M) state, the ordinary late receptor potential (LRP) is followed by a prolonged depolarizing afterpotential (PDA). The dependence of the amplitude of the PDA on the amount of pigment conversion is strongly supralinear, and the PDA duration also depends on this amount. These observations indicate an interaction among the elements of the PDA induction process and also make possible a test of the range of this interaction. The test consists of a comparison of the PDA after localized pigment conversion, obtained by strong spot illumination, to that after weaker diffuse illumination converting a comparable total amount of pigment. The experiment was performed on the barnacle lateral eye. The effective spot size was measured by the early receptor potential (ERP), in seawater saturated with CO2, which considerably reduced the electrical coupling between the photoreceptors. The ERP was also used to determine whether there is diffusion of R molecules into the illuminated spot. The spot illumination induced a PDA with small amplitude and long duration, while no detectable PDA was induced by the diffuse light. This indicates that the range of the PDA interaction is much smaller than the entire cell. In addition, the ERP results showed that there was no detectable diffusion of R molecules into the illuminated spot area over 30 min. This measurement, with a calculated correction for the microvillar geometry of the photoreceptor, enabled us to put an upper limit on the diffusion coefficient of the pigment molecules in the inact, unfixed barnacle photoreceptor of D less than 6 X 10(-9) cm2 s-1. PMID:3958692

  19. Prolonged lobar hypoxia in vivo enhances the responsivity of isolated pulmonary veins to hypoxia

    NASA Technical Reports Server (NTRS)

    Sheehan, D. W.; Farhi, L. E.; Russell, J. A.

    1992-01-01

    The hypoxic response of pulmonary vessels isolated from eight sheep whose right apical lobes (RAL) had inspired 100% N2 for 20 h was studied. The RAL of these conscious sheep inspired hypoxic gas and the remainder of the lung inspired air. During hypoxia, RAL perfusion was 33 +/- 3% of its air value, carotid arterial PO2 averaged 86 +/- 3 mm Hg and pulmonary perfusion pressure was not significantly different from the initial control period when the RAL inspired air. At the end of the hypoxic exposure, the sheep were killed, and pulmonary artery and vein rings (0.5 to 2 mm inner diameter) were isolated from both the RAL and the right cardiac lobe, which served as the control lobe (CL). Arteries from the RAL and CL did not contract in response to 6% O2/6% CO2/88% N2 (hypoxia). In contrast, RAL veins did contract vigorously in response to hypoxia, whereas CL veins did not contract or contracted only minimally. Rubbing of the endothelium or prior incubation of RAL veins with catalase (1,200 units/ml), indomethacin (10(-5) M), or the thromboxane A2/prostaglandin H2 (TxA2/PGH2) receptor antagonist, SQ 29,548 (3 X 10(-6) M) each significantly reduced the response to hypoxia. RAL veins were also found to be more reactive than CL veins to the prostaglandin endoperoxide analogue U46619. We conclude that prolonged lobar hypoxia in vivo increases the responsivity of isolated pulmonary veins to hypoxia. These contractions may result from an increase in reactive O2 species, which in turn modify production of, metabolism of, and/or tissue responsivity to TxA2/PGH2.

  20. Vestibulo-Cervico-Ocular Responses and Tracking Eye Movements after Prolonged Exposure to Microgravity

    NASA Technical Reports Server (NTRS)

    Kornilova, L. N.; Naumov, I. A.; Azarov, K. A.; Sagalovitch, S. V.; Reschke, Millard F.; Kozlovskaya, I. B.

    2007-01-01

    The vestibular function and tracking eye movements were investigated in 12 Russian crew members of ISS missions on days 1(2), 4(5-6), and 8(9-10) after prolonged exposure to microgravity (126 to 195 days). The spontaneous oculomotor activity, static torsional otolith-cervico-ocular reflex, dynamic vestibulo-cervico-ocular responses, vestibular reactivity, tracking eye movements, and gaze-holding were studied using videooculography (VOG) and electrooculography (EOG) for parallel eye movement recording. On post-flight days 1-2 (R+1-2) some cosmonauts demonstrated: - an increased spontaneous oculomotor activity (floating eye movements, spontaneous nystagmus of the typical and atypical form, square wave jerks, gaze nystagmus) with the head held in the vertical position; - suppressed otolith function (absent or reduced by one half amplitude of torsional compensatory eye counter-rolling) with the head inclined statically right- or leftward by 300; - increased vestibular reactivity (lowered threshold and increased intensity of the vestibular nystagmus) during head turns around the longitudinal body axis at 0.125 Hz; - a significant change in the accuracy, velocity, and temporal characteristics of the eye tracking. The pattern, depth, dynamics, and velocity of the vestibular function and tracking eye movements recovery varied with individual participants in the investigation. However, there were also regular responses during readaptation to the normal gravity: - suppression of the otolith function was typically accompanied by an exaggerated vestibular reactivity; - the structure of visual tracking (the accuracy of fixational eye rotations, smooth tracking, and gaze-holding) was disturbed (the appearance of correcting saccades, the transition of smooth tracking to saccadic tracking) only in those cosmonauts who, in parallel to an increased reactivity of the vestibular input, also had central changes in the oculomotor system (spontaneous nystagmus, gaze nystagmus).

  1. Body fineness ratio as a predictor of maximum prolonged-swimming speed in coral reef fishes.

    PubMed

    Walker, Jeffrey A; Alfaro, Michael E; Noble, Mae M; Fulton, Christopher J

    2013-01-01

    The ability to sustain high swimming speeds is believed to be an important factor affecting resource acquisition in fishes. While we have gained insights into how fin morphology and motion influences swimming performance in coral reef fishes, the role of other traits, such as body shape, remains poorly understood. We explore the ability of two mechanistic models of the causal relationship between body fineness ratio and endurance swimming-performance to predict maximum prolonged-swimming speed (Umax ) among 84 fish species from the Great Barrier Reef, Australia. A drag model, based on semi-empirical data on the drag of rigid, submerged bodies of revolution, was applied to species that employ pectoral-fin propulsion with a rigid body at U max. An alternative model, based on the results of computer simulations of optimal shape in self-propelled undulating bodies, was applied to the species that swim by body-caudal-fin propulsion at Umax . For pectoral-fin swimmers, Umax increased with fineness, and the rate of increase decreased with fineness, as predicted by the drag model. While the mechanistic and statistical models of the relationship between fineness and Umax were very similar, the mechanistic (and statistical) model explained only a small fraction of the variance in Umax . For body-caudal-fin swimmers, we found a non-linear relationship between fineness and Umax , which was largely negative over most of the range of fineness. This pattern fails to support either predictions from the computational models or standard functional interpretations of body shape variation in fishes. Our results suggest that the widespread hypothesis that a more optimal fineness increases endurance-swimming performance via reduced drag should be limited to fishes that swim with rigid bodies.

  2. Prolonged reduction of motion sickness sensitivity by visual-vestibular interaction

    PubMed Central

    Raphan, Ted; Cohen, Bernard

    2011-01-01

    The angular vestibulo-ocular reflex (aVOR) and optokinetic nystagmus (OKN) were elicited simultaneously at low frequencies to study effects of habituation of the velocity storage time constant in the vestibular system on motion sickness. Twenty-nine subjects, eleven of whom were susceptible to motion sickness from common transportation, were habituated by sinusoidal rotation at 0.017 Hz at peak velocities from 5 to 20°/s, while they watched a full-field OKN stimulus. The OKN stripes rotated in the same direction and at the same frequency as the subjects, but at a higher velocity. This produced an OKN opposite in direction to the aVOR response. Motion sickness sensitivity was evaluated with off-vertical axis rotation (OVAR) and by the response to transportation before and after 5 days of visual-vestibular habituation. Habituation did not induce motion sickness or change the aVOR gains, but it shortened the vestibular time constants in all subjects. This greatly reduced motion sickness produced by OVAR and sensitivity to common transport in the motion susceptible subjects, which persisted for up to 18 weeks. Two motion susceptible subjects who only had aVOR/OKN habituation without being tested with OVAR also became asymptomatic. Normal subjects who were not habituated had no reduction in either their aVOR time constants or motion sickness sensitivity. The opposing aVOR/OKN stimulation, which has not been studied before, was well tolerated, and for the first time was an effective technique for rapid and prolonged habituation of motion sickness without exposure to drugs or other nauseating habituation stimuli. PMID:21287155

  3. Prolonged self-paced exercise in the heat - environmental factors affecting performance.

    PubMed

    Junge, Nicklas; Jørgensen, Rasmus; Flouris, Andreas D; Nybo, Lars

    2016-01-01

    In this review we examine how self-paced performance is affected by environmental heat stress factors during cycling time trial performance as well as considering the effects of exercise mode and heat acclimatization. Mean power output during prolonged cycling time trials in the heat (≥30°C) was on average reduced by 15% in the 14 studies that fulfilled the inclusion criteria. Ambient temperature per se was a poor predictor of the integrated environmental heat stress and 2 of the prevailing heat stress indices (WBGT and UTCI) failed to predict the environmental influence on performance. The weighing of wind speed appears to be too low for predicting the effect for cycling in trained acclimatized subjects, where performance may be maintained in outdoor time trials at ambient temperatures as high as 36°C (36°C UTCI; 28°C WBGT). Power output during indoor trials may also be maintained with temperatures up to at least 27°C when humidity is modest and wind speed matches the movement speed generated during outdoor cycling, whereas marked reductions are observed when air movement is minimal. For running, representing an exercise mode with lower movement speed and higher heat production for a given metabolic rate, it appears that endurance is affected even at much lower ambient temperatures. On this basis we conclude that environmental heat stress impacts self-paced endurance performance. However, the effect is markedly modified by acclimatization status and exercise mode, as the wind generated by the exercise (movement speed) or the environment (natural or fan air movement) exerts a strong influence.

  4. Kaolinite ingestion facilitates restoration of body energy reserves during refeeding after prolonged fasting.

    PubMed

    Reichardt, François; Chaumande, Bertrand; Habold, Caroline; Robin, Jean-Patrice; Ehret-Sabatier, Laurence; Le Maho, Yvon; Liewig, Nicole; Angel, Fabielle; Lignot, Jean-Hervé

    2012-10-01

    Clay consumption is a spontaneous behavior currently observed in animals and humans, particularly during undernutrition. Often regarded as intestinal care products, ingested clays also enhance food efficiency, notably by increasing intestinal lipid uptake. Clay complementation could then optimize the reconstitution of energy reserves in animals with low lipid stocks consecutive to intensive fasting. The aim of this study was therefore to observe the effects of voluntarily kaolinite complementation during the refeeding of fasted rats to determine whether body mass, food uptake, lipid and mineral contents as intestinal morphology and protein profile were modified. This study examined two types of refeeding experiments after prolonged fasting. Firstly, rats with ad libitum access to food were compared to rats with ad libitum access to food and kaolinite pellets. Animals were randomly put into the different groups when the third phase of fasting (phase III) reached by each individual was detected. In a second set of experiments, rats starting phase III were refed with free access to food and kaolinite pellets. When animals had regained their body mass prior to fasting, they were euthanized for chemical, morphological, and proteomic analyses. Although kaolinite ingestion did not change the time needed for regaining prefasting body mass, daily food ingestion was seen to decrease by 6.8% compared with normally refed rats, without affecting lipid composition. Along the intestinal lining, enterocytes of complemented animals contained abundant lipid droplets and a structural modification of the brushborder was observed. Moreover, the expression of two apolipoproteins involved in lipid transport and satiety (ApoA-I and ApoA-IV) increased in complemented rats. These results suggest that kaolinite complementation favors intestinal nutrient absorption during refeeding despite reduced food uptake. Within the intestinal lumen, clay particles could increase the passive absorption

  5. Prolonged Sitting is Associated with Attenuated Heart Rate Variability during Sleep in Blue-Collar Workers

    PubMed Central

    Hallman, David M; Sato, Tatiana; Kristiansen, Jesper; Gupta, Nidhi; Skotte, Jørgen; Holtermann, Andreas

    2015-01-01

    Prolonged sitting is associated with increased risk for cardiovascular diseases and mortality. However, research into the physiological determinants underlying this relationship is still in its infancy. The aim of the study was to determine the extent to which occupational and leisure-time sitting are associated with nocturnal heart rate variability (HRV) in blue-collar workers. The study included 138 blue-collar workers (mean age 45.5 (SD 9.4) years). Sitting-time was measured objectively for four days using tri-axial accelerometers (Actigraph GT3X+) worn on the thigh and trunk. During the same period, a heart rate monitor (Actiheart) was used to sample R-R intervals from the electrocardiogram. Time and frequency domain indices of HRV were only derived during nighttime sleep, and used as markers of cardiac autonomic modulation. Regression analyses with multiple adjustments (age, gender, body mass index, smoking, job-seniority, physical work-load, influence at work, and moderate-to-vigorous physical activity) were used to investigate the association between sitting time and nocturnal HRV. We found that occupational sitting-time was negatively associated (p < 0.05) with time and frequency domain HRV indices. Sitting-time explained up to 6% of the variance in HRV, independent of the covariates. Leisure-time sitting was not significantly associated with any HRV indices (p > 0.05). In conclusion, objectively measured occupational sitting-time was associated with reduced nocturnal HRV in blue-collar workers. This indicates an attenuated cardiac autonomic regulation with increasing sitting-time at work regardless of moderate-to-vigorous physical activity. The implications of this association for cardiovascular disease risk warrant further investigation via long-term prospective studies and intervention studies. PMID:26610534

  6. Consequential secondary structure alterations and aggregation during prolonged casein glycation.

    PubMed

    Jindal, Supriya; Naeem, Aabgeena

    2013-05-01

    Non-enzymatic glycosylation (glycation) of casein is a process used not just to ameliorate the quality of dairy products but also to increase the shelf life of canned foods, including baby milk supplements. Incubation of κ-casein with reducing sugars for 15 days at physiological temperature showed the formation of a molten globule state at day 9 and 12 during fructation and glucation respectively. This state exhibits substantial secondary structure and maximum ANS binding. Later on, glycation resulted in the formation of aggregates at day 12 in presence of fructose and day 15 in presence of glucose. Aggregates possess extensive β-sheet structure as revealed by far-UV CD and FTIR. These aggregates showed altered tryptophan environment, decrease ANS binding relative to molten globule state and increase in Thioflavin T fluorescence. Aggregates were also accompanied by the accumulation of AGEs, indicative of structural damage to the protein and formation of potentially harmful species at the physiological level. Fructose was more reactive than glucose and thus caused early and significant changes in the protein. From our studies, we conclude that controlling the extent of the Maillard reaction in the food industry is essential to counter its negative effects and expand its safety spectrum.

  7. Megakaryocyte impairment by eptifibatide-induced antibodies causes prolonged thrombocytopenia.

    PubMed

    Greinacher, Andreas; Fuerll, Birgitt; Zinke, Heike; Müllejans, Bernd; Krüger, William; Michetti, Noemi; Motz, Wolfgang; Schwertz, Hansjörg

    2009-08-06

    Glycoprotein (GP) IIbIIIa inhibitors are used in the treatment of acute coronary syndromes. Transient immune-mediated acute thrombocytopenia is a recognized side effect of GPIIbIIIa inhibitors. We provide evidence that GPIIbIIIa inhibitor-induced antibodies can affect megakaryocytes in the presence of eptifibatide. In a patient with acute coronary syndrome, acute thrombocytopenia occurred after a second exposure to eptifibatide 20 days after the initial treatment. Despite the short half-life of eptifibatide (t(1/2) = 2 hours), thrombocytopenia less than 5 x 10(9)/L and gastrointestinal and skin hemorrhage persisted for 4 days. Glycoprotein-specific enzyme-linked immunosorbent assay showed eptifibatide-dependent, GPIIbIIIa-specific antibodies. Bone marrow examination showed predominance of early megakaryocyte stages, and platelet transfusion resulted in an abrupt platelet count increase. Viability of cultured cord blood-derived megakaryocytes was reduced in the presence of eptifibatide and patient IgG fraction. These findings can be explained by impaired megakaryocytopoiesis complicating anti-GPIIbIIIa antibody-mediated immune thrombocytopenia. This mechanism may also apply to some patients with autoimmune thrombocytopenia.

  8. Suspended sediment prolongs larval development in a coral reef fish.

    PubMed

    Wenger, Amelia S; McCormick, Mark I; Endo, Geoffrey G K; McLeod, Ian M; Kroon, Frederieke J; Jones, Geoffrey P

    2014-04-01

    Increasing sediment input into coastal environments is having a profound influence on shallow marine habitats and associated species. Coral reef ecosystems appear to be particularly sensitive, with increased sediment deposition and re-suspension being associated with declines in the abundance and diversity of coral reef fishes. While recent research has demonstrated that suspended sediment can have negative impacts on post-settlement coral reef fishes, its effect on larval development has not been investigated. In this study, we tested the effects of different levels of suspended sediment on larval growth and development time in Amphiprion percula, a coral reef damselfish. Larvae were subjected to four experimental concentrations of suspended sediment spanning the range found around coastal coral reefs (0-45 mg l(-1)). Larval duration was significantly longer in all sediment treatments (12 days) compared with the average larval duration in the control treatment (11 days). Approximately 75% of the fish in the control had settled by day 11, compared with only 40-46% among the sediment treatments. In the highest sediment treatment, some individuals had a larval duration twice that of the median duration in the control treatment. Unexpectedly, in the low sediment treatment, fish at settlement were significantly longer and heavier compared with fish in the other treatments, suggesting delayed development was independent of individual condition. A sediment-induced extension of the pelagic larval stage could significantly reduce numbers of larvae competent to settle and, in turn, have major effects on adult population dynamics.

  9. Effects of the New Aldose Reductase Inhibitor Benzofuroxane Derivative BF-5m on High Glucose Induced Prolongation of Cardiac QT Interval and Increase of Coronary Perfusion Pressure

    PubMed Central

    Di Filippo, C.; Ferraro, B.; Maisto, R.; Trotta, M. C.; Di Carluccio, N.; Sartini, S.; La Motta, C.; Ferraraccio, F.; Rossi, F.; D'Amico, M.

    2016-01-01

    This study investigated the effects of the new aldose reductase inhibitor benzofuroxane derivative 5(6)-(benzo[d]thiazol-2-ylmethoxy)benzofuroxane (BF-5m) on the prolongation of cardiac QT interval and increase of coronary perfusion pressure (CPP) in isolated, high glucose (33.3 mM D-glucose) perfused rat hearts. BF-5m was dissolved in the Krebs solution at a final concentration of 0.01 μM, 0.05 μM, and 0.1 μM. 33.3 mM D-glucose caused a prolongation of the QT interval and increase of CPP up to values of 190 ± 12 ms and 110 ± 8 mmHg with respect to the values of hearts perfused with standard Krebs solution (11.1 mM D-glucose). The QT prolongation was reduced by 10%, 32%, and 41%, respectively, for the concentration of BF-5m 0.01 μM, 0.05 μM, and 0.1 μM. Similarly, the CPP was reduced by 20% for BF-5m 0.05 μM and by 32% for BF-5m 0.1 μM. BF-5m also increased the expression levels of sirtuin 1, MnSOD, eNOS, and FOXO-1, into the heart. The beneficial actions of BF-5m were partly abolished by the pretreatment of the rats with the inhibitor of the sirtuin 1 activity EX527 (10 mg/kg/day/7 days i.p.) prior to perfusion of the hearts with high glucose + BF-5m (0.1 μM). Therefore, BF-5m supplies cardioprotection from the high glucose induced QT prolongation and increase of CPP. PMID:26839893

  10. Partial white and grey matter protection with prolonged infusion of recombinant human erythropoietin after asphyxia in preterm fetal sheep.

    PubMed

    Wassink, Guido; Davidson, Joanne O; Dhillon, Simerdeep K; Fraser, Mhoyra; Galinsky, Robert; Bennet, Laura; Gunn, Alistair J

    2017-03-01

    Perinatal asphyxia in preterm infants remains a significant contributor to abnormal long-term neurodevelopmental outcomes. Recombinant human erythropoietin has potent non-haematopoietic neuroprotective properties, but there is limited evidence for protection in the preterm brain. Preterm (0.7 gestation) fetal sheep received sham asphyxia (sham occlusion) or asphyxia induced by umbilical cord occlusion for 25 min, followed by an intravenous infusion of vehicle (occlusion-vehicle) or recombinant human erythropoietin (occlusion-Epo, 5000 international units by slow push, then 832.5 IU/h), starting 30 min after asphyxia and continued until 72 h. Recombinant human erythropoietin reduced neuronal loss and numbers of caspase-3-positive cells in the striatal caudate nucleus, CA3 and dentate gyrus of the hippocampus, and thalamic medial nucleus ( P < 0.05 vs. occlusion-vehicle). In the white matter tracts, recombinant human erythropoietin increased total, but not immature/mature oligodendrocytes ( P < 0.05 vs. occlusion-vehicle), with increased cell proliferation and reduced induction of activated caspase-3, microglia and astrocytes ( P < 0.05). Finally, occlusion-Epo reduced seizure burden, with more rapid recovery of electroencephalogram power, spectral edge frequency, and carotid blood flow. In summary, prolonged infusion of recombinant human erythropoietin after severe asphyxia in preterm fetal sheep was partially neuroprotective and improved electrophysiological and cerebrovascular recovery, in association with reduced apoptosis and inflammation.

  11. Involvement of metabotropic glutamate receptor 5 in the inhibition of methamphetamine-associated contextual memory after prolonged extinction training.

    PubMed

    Huang, Chien-Hsuan; Yu, Yang-Jung; Chang, Chih-Hua; Gean, Po-Wu

    2016-04-01

    Addiction is thought to be a memory process between perception and environmental cues and addicted patients often relapse when they come into contact with the drug-related context once again. Here, we used a conditioned place preference protocol to seek a more effective extinction methodology of methamphetamine (METH) memory and delineate its underlying mechanism. Conditioning METH for 3 days in mice markedly increased the time spent in the METH-paired compartment. Then the mice were conditioned with saline for 6 days, from day 6 to day 11, a procedure termed extinction training. However, METH memory returned after a priming injection of METH. We prolonged extinction duration from 6 to 10 days and found that this extensive extinction (EE) training prevented priming effect. At the molecular level, we discovered that prolonged extinction training reversed the METH-conditioned place preference-induced increase in surface expression of GluA2 and alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA)/NMDA ratio in the basolateral amygdala. In addition, we found that extinction with metabotropic glutamate receptor 5 (mGluR5) activation had similar results to EE: reduced relapse after extinction, decreased synaptic AMPA receptors AMPARs and the AMPA/NMDA ratio. On the contrary, EE with mGluR5 inhibition suppressed the results of EE. These data indicate that EE training-elicited inhibition of METH-primed reinstatement is mediated by the mGluR5. Conditioning mice with methamphetamine place preference (METH CPP) increases surface expression of AMPA receptors (AMPARs) in the basolateral amygdala. We found prolongation of extinction duration from 6 to 10 days prevented priming effect. At the molecular level, we discovered that extensive extinction (EE) reversed the METH CPP-induced increase in surface expression of GluA2 and AMPA/NMDA ratio. In addition, we found that extinction with the metabotropic glutamate receptor 5 (mGluR5) activation had similar results to EE

  12. Changes in sleep patterns during prolonged stays in Antarctica

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Moushum; Pal, Madhu Sudan; Sharma, Yogendra Kumar; Majumdar, Dhurjati

    2008-11-01

    Various countries have permanent research bases in Antarctica that are manned year-round by a few members of an expedition team, facing extremes of temperature with the associated hardships. Acclimatisation to such an environment is associated with pyschophysiological changes along with alterations in sleep patterns. The present study was undertaken to explore the changes in sleep patterns of six members of the Indian expedition team during their winter stay at Maitri, the permanent research station of India in Antarctica. The mean (± SEM) age, height and weight of the subjects were 35.7 ± 2.32 years, 168.3 ± 2.37 cm and 71.0 ± 1.88 kg, respectively. Polysomnographic sleep recordings were obtained as baseline data in November 2004 in Delhi (altitude 260 m, latitude 29° N, longitude 77° E); data on the same parameters were collected at Maitri, Antarctica (altitude 120 m, latitude 70° 45' 39″ S, longitude 11° 44' 49″ E) from January to December 2005. A one-way analysis of variance with repeated measures showed a significant variation with time (month effect) in most of the sleep parameters recorded. Total sleep time decreased from Delhi baseline values in all months, sleep efficiency decreased significantly during winter months, duration of waking period after sleep onset increased significantly in winter, sleep latency increased immediately after exposure in January, stages 3 and 4 (slow wave sleep) reduced during dark winter months, whereas stages 1 and 2 and rapid eye movement sleep increased during dark winter months. This study observed a prevailing general trend of sleep disturbances amongst overwintering members in a modern Antarctic station.

  13. Prolonged Survival of Campylobacter Species in Bovine Manure Compost ▿

    PubMed Central

    Inglis, G. Douglas; McAllister, Tim A.; Larney, Francis J.; Topp, Edward

    2010-01-01

    The persistence of naturally occurring campylobacteria in aerobic compost constructed of manure from beef cattle that were administered chlortetracycline and sulfamethazine (AS700) or from cattle not administered antibiotics (control) was examined. Although there were no differences in population sizes of heterotrophic bacteria, the temperature of AS700 compost was more variable and did not become as high as that of control compost. There were significant differences in water content, total carbon (C), total nitrogen (N), and electrical conductivity but not in the C/N ratio or pH between the two compost treatments. Campylobacteria were readily isolated from pen manure, for up to day 15 from control compost, and throughout the active phase of AS700 compost. Campylobacter DNA (including Campylobacter coli, Campylobacter fetus, Campylobacter hyointestinalis, and Campylobacter jejuni) was detected over the ca. 10-month composting period, and no reductions in quantities of C. jejuni DNA were observed over the duration of the active phase. The utilization of centrifugation in combination with ethidium monoazide (EMA) significantly reduced (>90%) the amplification of C. jejuni DNA that did not originate from cells with intact cell membranes. No differences were observed in the frequency of Campylobacter DNA detection between EMA- and non-EMA-treated samples, suggesting that Campylobacter DNA amplified from compost was extracted from cells with intact cell membranes (i.e., from viable cells). The findings of this study indicate that campylobacteria excreted in cattle feces persist for long periods in compost and call into question the common belief that these bacteria do not persist in manure. PMID:20023098

  14. Prolonged red cell storage before transfusion increases extravascular hemolysis

    PubMed Central

    Rapido, Francesca; Brittenham, Gary M.; Bandyopadhyay, Sheila; La Carpia, Francesca; L’Acqua, Camilla; McMahon, Donald J.; Rebbaa, Abdelhadi; Wojczyk, Boguslaw S.; Netterwald, Jane; Wang, Hangli; Schwartz, Joseph; Eisenberger, Andrew; Soffing, Mark; Yeh, Randy; Divgi, Chaitanya; Ginzburg, Yelena Z.; Shaz, Beth H.; Sheth, Sujit; Francis, Richard O.; Spitalnik, Steven L.; Hod, Eldad A.

    2016-01-01

    BACKGROUND. Some countries have limited the maximum allowable storage duration for red cells to 5 weeks before transfusion. In the US, red blood cells can be stored for up to 6 weeks, but randomized trials have not assessed the effects of this final week of storage on clinical outcomes. METHODS. Sixty healthy adult volunteers were randomized to a single standard, autologous, leukoreduced, packed red cell transfusion after 1, 2, 3, 4, 5, or 6 weeks of storage (n = 10 per group). 51-Chromium posttransfusion red cell recovery studies were performed and laboratory parameters measured before and at defined times after transfusion. RESULTS. Extravascular hemolysis after transfusion progressively increased with increasing storage time (P < 0.001 for linear trend in the AUC of serum indirect bilirubin and iron levels). Longer storage duration was associated with decreasing posttransfusion red cell recovery (P = 0.002), decreasing elevations in hematocrit (P = 0.02), and increasing serum ferritin (P < 0.0001). After 6 weeks of refrigerated storage, transfusion was followed by increases in AUC for serum iron (P < 0.01), transferrin saturation (P < 0.001), and nontransferrin-bound iron (P < 0.001) as compared with transfusion after 1 to 5 weeks of storage. CONCLUSIONS. After 6 weeks of refrigerated storage, transfusion of autologous red cells to healthy human volunteers increased extravascular hemolysis, saturated serum transferrin, and produced circulating nontransferrin-bound iron. These outcomes, associated with increased risks of harm, provide evidence that the maximal allowable red cell storage duration should be reduced to the minimum sustainable by the blood supply, with 35 days as an attainable goal. REGISTRATION. ClinicalTrials.gov NCT02087514. FUNDING. NIH grant HL115557 and UL1 TR000040. PMID:27941245

  15. Thermoregulation during prolonged actual and laboratory-simulated bicycling.

    PubMed

    Brown, S L; Banister, E W

    1985-01-01

    Thermoregulatory and cardiorespiratory responses to bicycling 55 km (mean speed 9.7 m X s-1) outdoors (15 degrees C DB) were compared to equivalent cycle ergometry (90 min at 65% VO2max) in the laboratory (20-23 degrees C DB, 50% RH) in 7 trained cyclists. Outdoor environmental conditions were simulated with fans and lamps, and were contrasted with standard no-wind, no-sun laboratory conditions. Sweating rate was similar during outdoor and laboratory simulated outdoor cycling (0.90 and 0.87 to 0.94 1 X h-1 respectively). During outdoor bicycling, mean heart rate (161 bt X min-1) was 7-13% higher (p less than .05) than under laboratory conditions, suggesting a greater strain for a similar external work rate. The increase in rectal temperature (0.8 degrees C) was 33-50% less (p less than 0.05) at the cooler outdoor ambient temperature than in the laboratory. Thermoregulatory stress was greater under the no-fan, no-lamp laboratory condition than during simulated outdoor conditions (36-38% greater (p less than 0.05) sweating rate, 15-18% greater (p less than 0.01) mean skin temperature, 6.4 to 7.8 fold greater (p less than 0.01) amount of clothing-retrained sweat). The cooling wind encountered in actual road bicycling apparently reduces thermoregulatory and circulatory demands compared with stationary cycle ergometry indoors. Failure to account for this enhanced cooling may result in overestimation of the physiological stress of actual road cycling.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Carry-over fluency induced by extreme prolongations: A new behavioral paradigm.

    PubMed

    Briley, P M; Barnes, M P; Kalinowski, J S

    2016-04-01

    Extreme prolongations, which can be generated via extreme delayed auditory feedback (DAF) (e.g., 250-500 ms) or mediated cognitively with timing applications (e.g., analog stopwatch) at 2 s per syllable, have long been behavioral techniques used to inhibit stuttering. Some therapies have used this rate solely to establish initial fluency, while others use extremely slowed speech to establish fluency and add other strategic techniques such as easy onsets and diaphragmatic breathing. Extreme prolongations generate effective, efficient, and immediate forward flowing fluent speech, removing the signature behaviors of discrete stuttering (i.e., syllable repetitions and audible and inaudible postural fixations). Prolonged use of extreme prolongations establishes carry-over fluency, which is spontaneous, effortless speech absent of most, if not all, overt and covert manifestations of stuttering. The creation of this immediate fluency and the immense potential of extreme prolongations to generate long periods of carry-over fluency have been overlooked by researchers and clinicians alike. Clinicians depart from these longer prolongation durations as they attempt to achieve the same fluent results at a near normal rate of speech. Clinicians assume they are re-teaching fluency and slow rates will give rise to more normal rates with less control, but without carry-over fluency, controls and cognitive mediation are always needed for the inherently unstable speech systems of persons who stutter to experience fluent speech. The assumption being that the speech system is untenable without some level of cognitive and motoric monitoring that is always necessary. The goal is omnipresent "near normal rate sounding fluency" with continuous mediation via cognitive and motoric processes. This pursuit of "normal sounding fluency" continues despite ever-present relapse. Relapse has become so common that acceptance of stuttering is the new therapy modality because relapse has come to be

  17. Forearm training attenuates sympathetic responses to prolonged rhythmic forearm exercise

    NASA Technical Reports Server (NTRS)

    Sinoway, L.; Shenberger, J.; Leaman, G.; Zelis, R.; Gray, K.; Baily, R.; Leuenberger, U.

    1996-01-01

    We previously demonstrated that nonfatiguing rhythmic forearm exercise at 25% maximal voluntary contraction (12 2-s contractions/min) evokes sympathoexcitation without significant engagement of metabolite-sensitive muscle afferents (B.A. Batman, J.C. Hardy, U.A. Leuenberger, M.B. Smith, Q.X. Yang and L.I. Sinoway. J. Appl. Physiol. 76: 1077-1081, 1994). This is in contrast to the sympathetic nervous system responses observed during fatiguing static forearm exercise where metabolite-sensitive afferents are the key determinants of sympathetic activation. In this report we examined whether forearm exercise training would attenuate sympathetic nervous system responses to rhythmic forearm exercise. We measured heart rate, mean arterial blood pressure (MAP), muscle sympathetic nerve activity (microneurography), plasma norepinephrine (NE), and NE spillover and clearance (tritiated NE kinetics) during nonfatiguing rhythmic forearm exercise before and after a 4-wk unilateral forearm training paradigm. Training had no effect on forearm mass, maximal voluntary contraction, or heart rate but did attenuate the increase in MAP (increase in MAP: from 15.2 +/- 1.8 before training to 11.4 +/- 1.4 mmHg after training; P < 0.017), muscle sympathetic nerve activity (increase in bursts: from 10.8 +/- 1.4 before training to 6.2 +/- 1.1 bursts/min after training; P < 0.030), and the NE spillover (increases in arterial spillover: from 1.3 +/- 0.2 before training to 0.6 +/- 0.2 nmol.min-1.m-2 after training, P < 0.014; increase in venous spillover: from 2.0 +/- 0.6 before training to 1.0 +/- 0.5 nmol.min-1.m-2 after training, P < 0.037) seen in response to exercise performed by the trained forearm. Thus forearm training reduces sympathetic responses during a nonfatiguing rhythmic handgrip paradigm that does not engage muscle metaboreceptors. We speculate that this effect is due to a conditioning-induced reduction in mechanically sensitive muscle afferent discharge.

  18. Prolonging β-lactam infusion: a review of the rationale and evidence, and guidance for implementation.

    PubMed

    MacVane, Shawn H; Kuti, Joseph L; Nicolau, David P

    2014-02-01

    Given the sparse antibiotic pipeline and the increasing prevalence of resistant organisms, efforts should be made to optimise the pharmacodynamic exposure of currently available agents. Prolonging the infusion duration is a strategy used to increase the percentage of the dosing interval that free drug concentrations remain above the minimum inhibitory concentration (fT>MIC), the pharmacodynamic efficacy driver for time-dependent antibiotics such as β-lactams. β-Lactams, the most commonly prescribed class of antibiotics owing to their efficacy and safety profile, have been the mainstay of therapy since the discovery of penicillin over 60 years ago. Mounting evidence, including the use of population pharmacokinetic modelling and Monte Carlo simulation, suggests that prolonging the infusion time of β-lactam antibiotics may have advantages over standard infusion techniques, including an enhanced probability of achieving requisite fT>MIC exposures, lower mortality and potentially reductions in infection/antibiotic-related costs. As a result of these favourable attributes, clinical practice guidelines support the use of prolonged-infusion β-lactams in the treatment of many severe infections. This article discusses the rationale and evidence for prolonging the infusion of β-lactam antibiotics and provides guidance for the implementation of a prolonged-infusion programme.

  19. Prolongation Structure of a Generalised Inhomogeneous Gardner Equation in Plasmas and Fluids

    NASA Astrophysics Data System (ADS)

    Xie, Xi-Yang; Tian, Bo; Sun, Wen-Rong; Wang, Yun-Po

    2016-04-01

    In this article, the prolongation structure technique is applied to a generalised inhomogeneous Gardner equation, which can be used to describe certain physical situations, such as the stratified shear flows in ocean and atmosphere, ion acoustic waves in plasmas with a negative ion, interfacial solitary waves over slowly varying topographies, and wave motion in a non-linear elastic structural element with large deflection. The Lax pairs, which are derived via the prolongation structure, are more general than the Lax pairs published before. Under the Painlevé conditions, the linear-damping coefficient equals to zero, the quadratic non-linear coefficient is proportional to the dispersive coefficient c(t), the cubic non-linear coefficient is proportional to c(t), leaving no constraints on c(t) and the dissipative coefficient d(t). We establish the prolongation structure through constructing the exterior differential system. We introduce two methods to obtain the Lax pairs: (a) based on the prolongation structure, the Lax pairs are obtained, and (b) via the Lie algebra, we can derive the Pfaffian forms and Lax pairs when certain parameters are chosen. We set d(t) as a constant to discuss the influence of c(t) on the Pfaffian forms and Lax pairs, and to discuss the influence of d(t) on the Pfaffian forms and Lax pairs, we set c(t) as another constant. Then, we get different prolongation structure, Pfaffian forms and Lax pairs.

  20. A detailed description and assessment of outcomes of patients with hospital recorded QTc prolongation.

    PubMed

    Laksman, Zachary; Momciu, Bogdan; Seong, You Won; Burrows, Patricia; Conacher, Susan; Manlucu, Jaimie; Leong-Sit, Peter; Gula, Lorne J; Skanes, Allan C; Yee, Raymond; Klein, George J; Krahn, Andrew D

    2015-04-01

    Corrected QT (QTc) interval prolongation has been shown to be an independent predictor of mortality in many clinical settings and is a common finding in hospitalized patients. The causes and outcomes of patients with extreme QTc interval prolongation during a hospital admission are poorly described. The aim of this study was to prospectively identify patients with automated readings of QTc intervals >550 ms at 1 academic tertiary hospital. One hundred seventy-two patients with dramatic QTc interval prolongation (574 ± 53 ms) were identified (mean age 67.6 ± 15.1 years, 48% women). Most patients had underlying heart disease (60%), predominantly ischemic cardiomyopathy (43%). At lease 1 credible and presumed reversible cause associated with QTc interval prolongation was identified in 98% of patients. The most common culprits were QTc interval-prolonging medications, which were deemed most responsible in 48% of patients, with 25% of these patients taking ≥2 offending drugs. Two patients were diagnosed with congenital long-QT syndrome. Patients with electrocardiograms available before and after hospital admission demonstrated significantly lower preadmission and postdischarge QTc intervals compared with the QTc intervals recorded in the hospital. In conclusion, in-hospital mortality was high in the study population (29%), with only 4% of patients experiencing arrhythmic deaths, all of which were attributed to secondary causes.

  1. Tolerability to prolonged lifting tasks. A validation of the recommended limits.

    PubMed

    Capodaglio, P; Bazzini, G

    1997-01-01

    Prolonged physical exertion is subjectively regulated by the perception of effort. This preliminary study was conducted to validate the use of subjective perceptions of effort in assessing objectively tolerable workloads for prolonged lifting tasks. Ten healthy male subjects tested their maximal lifting capacity (MLC) on a lift dynamometer (LidoLift, Loredan Biomed., West Sacramento, CA) and underwent incremental and 30-minute endurance lifting tests. Cardiorespiratory parameters were monitored with an oxygen uptake analyzer, mechanical parameters were calculated using a computerized dynamometer. Ratings of perceived exertion were given on Borg's 10-point scale. Physiological responses to repetitive lifting were matched with subjective perceptions. A single-variable statistical regression for power functions was performed to obtain the individual "iso-perception" curves as functions of the mechanical work exerted. We found that the "iso-perception" curve corresponding to a "moderate" perception of effort may represent the individual "tolerance threshold" for prolonged lifting tasks, since physiological responses at this level of intensity did not change significantly and the respiratory exchange ratio was less than one. The individually tolerable weight for lifting tasks lasting 30 min has been expressed as a percentage of the isoinertial MLC value and compared with the currently recommended limits for prolonged lifting tasks (Italian legislation D.L. 626/94). On the basis of our preliminary results a "tolerance threshold" of 20% MLC has been proposed for prolonged lifting tasks.

  2. Prolonged minor allograft survival in intravenously primed mice--a test of the veto hypothesis

    SciTech Connect

    Johnson, L.L.

    1987-07-01

    Experiments were performed to test the hypothesis that veto cells are responsible for the prolonged survival of minor allografts of skin that is observed in recipients primed intravenously with spleen cells from mice syngeneic with the skin donors. This prolonged survival was observed for each of several minor histocompatibility (H) antigens and is antigen-specific. Gamma radiation (3300 rads) abolished the ability of male spleen cells infused i.v. to delay the rejection of male skin grafts (H-Y antigen) on female recipients. However, depletion of Thy-1+ cells from the i.v. infusion failed to abolish the ability to prolong male skin graft survival. Furthermore, the prolonged survival accorded to B6 (H-2b) male skin grafts on CB6F1 (H-2b/H-2d) female recipients given i.v. infusions of B6 male spleen cells extended to BALB/c (H-2d) male skin grafts as well, indicating a lack of MHC restriction. Thus, prolongation of minor allograft survival by i.v. infusion of minor H antigen-bearing spleen cells appears not to depend on veto T cells that others have found to be responsible for the suppression of CTL generation.

  3. Impact of Prolonged Temporal Discrimination Threshold on Finger Movements of Parkinson’s Disease

    PubMed Central

    Lee, M. J.; Son, J. S.; Lee, J. H.; Kim, S. J.; Lyoo, C. H.; Lee, M. S.

    2016-01-01

    Introduction Sensory information is essential for the precise control of movement. Patients with Parkinson’s disease (PD) have higher-order sensory dysfunctions including prolonged temporal discrimination threshold (TDT). However, the impact of prolonged TDT on parkinsonian motor deficits is uncertain. Methods This study includes 33 PD patients and 24 healthy controls. TDT values were measured in the index finger. Using coin rotation task (CRT), dexterous finger movement was assessed. Using an inertial sensor, the speed, amplitude, and frequency of finger tapping were measured. The impact of prolonged index finger TDT on two different finger movements was analyzed using the general estimating equation. Results Compared to healthy controls, TDT was prolonged in the PD patients. There was no impact of TDT on mean values or decrement for amplitude and speed, as well as mean values, decrement and variability of tapping frequency. However, prolonged TDT had a significant impact on the variability in amplitude (B = 436.905 × 10−4, Wald χ2 = 9.140, p = 0.014) and speed (B = 425.655 × 10−4, Wald χ2 = 9.876, p = 0.014) of finger tapping. There was a marginal correlation between TDT and CRT. In addition, CRT correlated with variability in amplitude and speed of finger tapping. Conclusion In PD, cutaneous temporal discriminative sensory dysfunction appears to be related to increased variabilities in the speed and amplitude of fast repetitive finger movements and disturbed finger dexterity. PMID:27893840

  4. Metacognition, social cognition, and symptoms in patients with first episode and prolonged psychoses.

    PubMed

    Vohs, J L; Lysaker, P H; Francis, M M; Hamm, J; Buck, K D; Olesek, K; Outcalt, J; Dimaggio, G; Leonhardt, B; Liffick, E; Mehdiyoun, N; Breier, A

    2014-03-01

    While it has been documented that persons with prolonged schizophrenia have deficits in metacognition and social cognition, it is less clear whether these difficulties are already present during a first episode. To explore this issue we assessed and compared metacognition using the Metacognition Assessment Scale-Abbreviated (MAS-A) and social cognition using the Eyes, Hinting and Bell-Lysaker Emotional Recognition Tests (BLERT) in participants with first episode psychosis (FEP; n=26), participants with a prolonged psychosis (n=72), and a psychiatric control group consisting of persons with a substance use disorder and no history of psychosis (n=14). Analyses revealed that both psychosis cohorts scored lower than controls on the MAS-A total and all subscales except metacognitive mastery. Compared to the FEP group, the persons with prolonged psychosis demonstrated greater metacognitive capacities only in those MAS-A domains reflective of the ability to understand the mental state of others and to see that others may have motivations and desires separate from their own. Other domains of metacognition did not differ between psychosis groups. The Eyes, Hinting and BLERT scores of the two psychosis groups did not differ but were poorer than those produced by the control group. Exploratory correlations in the FEP group showed a pattern similar to that previously observed in prolonged psychosis. Taken together, these findings suggest that while certain domains of metacognition could improve with prolonged psychosis, difficulties with global metacognition and social cognition may be stable features of the disorder and perhaps unique to psychosis.

  5. Effect of prolonged exposure to organic solvents on the active site environment of subtilisin Carlsberg.

    PubMed

    Bansal, Vibha; Delgado, Yamixa; Fasoli, Ezio; Ferrer, Amaris; Griebenow, Kai; Secundo, Francesco; Barletta, Gabriel L

    2010-06-01

    The potential of enzyme catalysis as a tool for organic synthesis is nowadays indisputable, as is the fact that organic solvents affect an enzyme's activity, selectivity and stability. Moreover, it was recently realized that an enzyme's initial activity is substantially decreased after prolonged exposure to organic media, an effect that further hampers their potential as catalysts for organic synthesis. Regrettably, the mechanistic reasons for these effects are still debatable. In the present study we have made an attempt to explain the reasons behind the partial loss of enzyme activity on prolonged exposure to organic solvents. Fluorescence spectroscopic studies of the serine protease subtilisin Carlsberg chemically modified with polyethylene glycol (PEG-SC) and inhibited with a Dancyl fluorophore, and dissolved in two organic solvents (acetonitrile and 1,4-dioxane) indicate that when the enzyme is initially introduced into these solvents, the active site environment is similar to that in water; however prolonged exposure to the organic medium causes this environment to resemble that of the solvent in which the enzyme is dissolved. Furthermore, kinetic studies show a reduction on both V(max) and K(M) as a result of prolonged exposure to the solvents. One interpretation of these results is that during this prolonged exposure to organic solvents the active-site fluorescent label inhibitor adopts a different binding conformation. Extrapolating this to an enzymatic reaction we argue that substrates bind in a less catalytically favorable conformation after the enzyme has been exposed to organic media for several hours.

  6. Factors of working conditions and prolonged fatigue among teachers at public elementary and junior high schools.

    PubMed

    Shimizu, Midori; Wada, Koji; Wang, Guoqin; Kawashima, Masatoshi; Yoshino, Yae; Sakaguchi, Hiroko; Ohta, Hiroshi; Miyaoka, Hitoshi; Aizawa, Yoshiharu

    2011-01-01

    Prolonged fatigue among elementary and junior high school teachers not only damages their health but also affects the quality of education. The aim of this study was to determine the factors of working conditions associated with prolonged fatigue among teachers at public elementary and junior high schools. We distributed a self-reported, anonymous questionnaire to 3,154 teachers (1,983 in elementary schools, 1,171 in junior high schools) working in public schools in a city in Japan. They were asked to assess 18 aspects of their working conditions using a seven-point Likert scale. Prolonged fatigue was measured using the Japanese version of the checklist individual strength questionnaire. Multiple regression analysis was used to examine the association between working conditions and prolonged fatigue. Gender, age, and school type were introduced as confounders. In all, 2,167 teachers participated in this study. Results showed that qualitative and quantitative workload (time pressure due to heavy workload, interruptions, physically demanding job, extra work at home), communication with colleagues (poor communication, lack of support), and career factors (underestimation of performance by the board of education or supervisors, occupational position not reflecting training, lack of prospects for work, job insecurity) were associated with prolonged fatigue.

  7. Survival after prolonged pediatric extracorporeal membrane oxygenation support for adenoviral pneumonia.

    PubMed

    Allibhai, Taslim F; Spinella, Philip C; Meyer, Michael T; Hall, Brian H; Kofos, Daniel; DiGeronimo, Robert J

    2008-08-01

    Adenoviral pneumonia can cause significant pulmonary morbidity leading to extracorporeal membrane oxygenation (ECMO) rescue. Reported survival of adenoviral pneumonia requiring ECMO has been poor, and prolonged time on ECMO is associated with increased mortality. We present 2 pediatric cases of adenoviral pneumonia in patients who survived after greater than 30 days on ECMO and review the Extracorporeal Life Support Organization (ELSO) registry to describe the collective experience of children with viral pneumonia requiring prolonged ECMO. Although survival has improved over the past decade for pediatric adenoviral pneumonia, the ELSO database previously has had no surviving children reported with a primary diagnosis of adenovirus after more than 4 weeks on ECMO. Our experience suggests that there may be use for prolonged ECMO support in children despite severe adenoviral pneumonia.

  8. Prolonged-release hard gelatin capsules of furosemide for the treatment of dogs.

    PubMed

    Smal, J; Haapala, O; Marvola, M; Kuusela, S; Happonen, I

    1995-02-01

    The object of this study was to examine whether prolonged-release hard gelatin capsule formulations could be developed for dogs. Different viscosity grades of hydroxypropyl methylcellulose (HPMC) and sodium carboxymethylcellulose (NaCMC) were used to control drug release. Furosemide was chosen because of its wide use in the management of heart failure in dogs. In vitro, selecting different viscosity grades allowed good control of drug release, whereas in vivo the difference between formulations was clearly smaller. Although all formulations gave prolonged release, both inter- and intra-individual variation in the plasma concentration-time curves was high. It is difficult to develop prolonged-release formulations for drugs such as furosemide with highly variable pharmacokinetic properties. However, hard gelatin capsules containing hydrophilic polymers could still be a suitable choice for some drugs.

  9. Life Threatening Severe QTc Prolongation in Patient with Systemic Lupus Erythematosus due to Hydroxychloroquine

    PubMed Central

    O'Laughlin, John P.; Wong, Brian C.

    2016-01-01

    We present a case of a syncopal episode resulting from significant QT interval prolongation in a patient on hydroxychloroquine for the treatment of systemic lupus erythematosus and end stage renal disease. The patient had been treated with hydroxychloroquine for two years prior to presentation. After thorough workup for secondary causes of QT interval prolongation hydroxychloroquine was discontinued and the patient's QT interval shortened. The patient was treated with mexiletine to prevent sudden ventricular arrhythmias, which was unique compared to other documented cases in which lidocaine was used. The patient was noted to have mild prolongation of the QT interval on electrocardiogram prior to initiation of hydroxychloroquine therapy which was exacerbated by its use and may have been caused due to toxicity from underlying renal failure. PMID:27478650

  10. Effect of prolonged hypokinesia on resistance of resistive vessels in rats

    NASA Technical Reports Server (NTRS)

    Saltykova, V. A.

    1982-01-01

    Under the effect of prolonged hypokinesia, the perfusion pressure in resistive vessels, measured under conditions of deep anesthesia and complete denervation, increased by approximately the same degree as arterial pressure in non-anesthetized animals. The increase in arterial, perfusion pressure and the resistance of resistive vessels in animals subjected to prolonged hypokinesia was accompanied by an increase in adrenoreactivity. During prolonged hypokinesia, partial obliteration of the vascular bed of the skeletal muscles plays a significant role in the observed increase in resistance of vessels of the extremities. The increase in adrenoreactivity of the vessels during hypokinesia may be realized as a partial case of an increase in the adrenoreactivity of structures whose innervation is disturbed.

  11. Metabolic Consequences in Humans of Prolonged Sleep Restriction Combined with Circadian Disruption

    PubMed Central

    Buxton, Orfeu M.; Cain, Sean W.; O’Connor, Shawn P.; Porter, James H.; Duffy, Jeanne F.; Wang, Wei; Czeisler, Charles A.; Shea, Steven A.

    2013-01-01

    Epidemiological studies link short sleep and circadian disruption with risk of metabolic syndrome and diabetes. We tested the hypotheses that prolonged sleep restriction with concurrent circadian disruption, as can occur with shift work, impairs glucose regulation and metabolism. Healthy adults spent >5 weeks in controlled laboratory conditions including: sleep extension (baseline), 3-week sleep restriction (5.6 h sleep/24 h) combined with circadian disruption (recurring 28-h ‘days’), and 9-day recovery sleep with circadian re-entrainment. Prolonged sleep restriction with concurrent circadian disruption significantly decreased resting metabolic rate, and increased postprandial plasma via inadequate pancreatic beta cell responsivity; these normalized with 9 days of recovery sleep and stable circadian reentrainment. Thus, in humans, prolonged sleep restriction with concurrent circadian disruption alters metabolism and could increase risk of obesity and diabetes. PMID:22496545

  12. Overview of clinical efficacy and risk data of benzodiazepines for prolonged seizures.

    PubMed

    Lagae, Lieven

    2014-10-01

    An historical overview is provided regarding the use of benzodiazepines for the treatment of acute prolonged convulsive seizures. It is clear that intravenous benzodiazepines remain a first step for the in-hospital treatment of prolonged seizures or status epilepticus. However, in the community, in a pre-hospital situation, intravenous administration is not possible. In recent years, it was shown that rectal, buccal, intranasal, and intramuscular administration of benzodiazepines is very effective as a first and safe treatment step. In many cases, rectal diazepam is not socially acceptable anymore, and therefore more emphasis is now put on buccal, intranasal, and intramuscular administration. At present, based on the available data, midazolam is the product of choice for the acute treatment of prolonged convulsive seizures.

  13. Circadian, endocrine, and metabolic effects of prolonged bedrest: Two 56-day bedrest studies

    NASA Technical Reports Server (NTRS)

    Vernikos-Danellis, J.; Winget, C. M.; Leach, C. S.; Rambaut, P. C.

    1974-01-01

    Two bedrest studies of 56 days each have been conducted to evaluate the effects of prolonged bedrest on circadian synchrony and endocrine and metabolic function. Measurements included the pituitary-adrenal, thyroid, parathyroid, insulin-glucose-growth hormones, catecholamine excretion, body temperature, and heart rate. The results indicated that a rigorous regimen of exercise did not prevent the endocrine and metabolic effects of prolonged bedrest. Changes in circadian, endocrine, and metabolic functions in bedrest appear to be due to changes in hydrostatic pressure and lack of postural cues rather than to inactivity, confinement, or the bleeding schedule. Prolonged bedrest, particularly beyond 24 days, resulted in rhythm desynchronization in spite of well regulated light/dark cycles, temperature, humidity, activity, and meal times and meal composition and in increased lability of all endocrine parameter measured. It also resulted in an apparent insensitivity of the glucose response to insulin, of cortisol secretion to ACTH, and of growth hormone secretion to hypoglycemia.

  14. The personal and financial impact of repetitive or prolonged seizures on the patient and family.

    PubMed

    O'Dell, Christine; Wheless, James W; Cloyd, James

    2007-05-01

    Individuals with epilepsy consistently report diminished quality of life. The clinical characteristics of seizures and the unpredictable nature of seizure occurrences are some factors that affect quality of life. Prolonged or repetitive seizures can impose psychologic comorbidities, social issues, and lifestyle restrictions that can affect quality of life of patients and their caregivers and family members, who also bear the considerable indirect costs of seizures, including time away from work or school, and even loss of employment. The availability and use of an at-home medication to terminate prolonged or repetitive seizures or in seizure emergencies improves quality of life for patients and their families. Fewer visits to the emergency department are associated with a reduction in the financial burden to families and the health care system. This article discusses factors that contribute to the personal and financial impact of prolonged seizures on adult and pediatric patients, their families, and caregivers.

  15. Interventions to Reduce Sedentary Behavior

    PubMed Central

    Manini, Todd M.; Carr, Lucas J.; King, Abby C.; Marshall, Simon; Robinson, Thomas N.; Rejeski, W. Jack

    2014-01-01

    Purpose This paper reports on presentations and discussion from the working group on “Influences on Sedentary Behavior & Interventions” as part of the Sedentary Behavior: Identifying Research Priorities Workshop. Methods Interventions were discussed in the context of targeting sedentary behavior (SB) as a concept distinct from physical activity (PA). It was recommended that interventions targeting SB should consider a life course perspective, a position predicated on the assumption that SB is age and life stage dependent. Additionally, targeting environments where individuals have high exposure to SB— such as workplace sitting— could benefit from new technology (e.g., computer-based prompting to stand or move), environmental changes (e.g., active workstations), policies targeting reduced sedentary time (e.g., allowing employees regular desk breaks), or by changing norms surrounding prolonged sitting (e.g., standing meetings). Results & Conclusions There are limited data about the minimal amount of SB change required to produce meaningful health benefits. In addition to developing relevant scientific and public health definitions of SB, it is important to further delineate the scope of health and quality of life outcomes associated with reduced SB across the life course, and clarify what behavioral alternatives to SB can be used to optimize health gains. SB interventions will benefit from having more clarity about the potential physiological and behavioral synergies with current PA recommendations, developing multi-level interventions aimed at reducing SB across all life phases and contexts, harnessing relevant and effective strategies to extend the reach of interventions to all sectors of society, as well as applying state-of-the-science adaptive designs and methods to accelerate advances in the science of sedentary behavior interventions. PMID:25222818

  16. A novel B-domain O-glycoPEGylated FVIII (N8-GP) demonstrates full efficacy and prolonged effect in hemophilic mice models

    PubMed Central

    Kjalke, Marianne; Karpf, Ditte M.; Balling, Kristoffer W.; Johansen, Peter B.; Elm, Torben; Øvlisen, Kristine; Möller, Flemming; Holmberg, Heidi L.; Gudme, Charlotte N.; Persson, Egon; Hilden, Ida; Pelzer, Hermann; Rahbek-Nielsen, Henrik; Jespersgaard, Christina; Bogsnes, Are; Pedersen, Anette A.; Kristensen, Anne K.; Peschke, Bernd; Kappers, Wendy; Rode, Frederik; Thim, Lars; Tranholm, Mikael; Ezban, Mirella; Olsen, Eva H. N.; Bjørn, Søren E.

    2013-01-01

    Frequent infusions of intravenous factor VIII (FVIII) are required to prevent bleeding associated with hemophilia A. To reduce the treatment burden, recombinant FVIII with a longer half-life was developed without changing the protein structure. FVIII–polyethylene glycol (PEG) conjugates were prepared using an enzymatic process coupling PEG (ranging from 10 to 80 kDa) selectively to a unique O-linked glycan in the FVIII B-domain. Binding to von Willebrand factor (VWF) was maintained for all conjugates. Upon cleavage by thrombin, the B-domain and the associated PEG were released, generating activated FVIII (FVIIIa) with the same primary structure and specific activity as native FVIIIa. In both FVIII- and VWF-deficient mice, the half-life was found to increase with the size of PEG. In vivo potency and efficacy of FVIII conjugated with a 40-kDa PEG (N8-GP) and unmodified FVIII were not different. N8-GP had a longer duration of effect in FVIII-deficient mouse models, approximately a twofold prolonged half-life in mice, rabbits, and cynomolgus monkeys; however, the prolongation was less pronounced in rats. Binding capacity of N8-GP on human monocyte-derived dendritic cells was reduced compared with unmodified FVIII, resulting in several-fold reduced cellular uptake. In conclusion, N8-GP has the potential to offer efficacious prevention and treatment of bleeds in hemophilia A at reduced dosing frequency. PMID:23335368

  17. Prolonged fasting activates Nrf2 in post-weaned elephant seals.

    PubMed

    Vázquez-Medina, José Pablo; Soñanez-Organis, José G; Rodriguez, Ruben; Viscarra, Jose A; Nishiyama, Akira; Crocker, Daniel E; Ortiz, Rudy M

    2013-08-01

    Elephant seals naturally experience prolonged periods of absolute food and water deprivation (fasting). In humans, rats and mice, prolonged food deprivation activates the renin-angiotensin system (RAS) and increases oxidative damage. In elephant seals, prolonged fasting activates RAS without increasing oxidative damage likely due to an increase in antioxidant defenses. The mechanism leading to the upregulation of antioxidant defenses during prolonged fasting remains elusive. Therefore, we investigated whether prolonged fasting activates the redox-sensitive transcription factor Nrf2, which controls the expression of antioxidant genes, and if such activation is potentially mediated by systemic increases in RAS. Blood and skeletal muscle samples were collected from seals fasting for 1, 3, 5 and 7 weeks. Nrf2 activity and nuclear content increased by 76% and 167% at week 7. Plasma angiotensin II (Ang II) and transforming growth factor β (TGF-β) were 5000% and 250% higher at week 7 than at week 1. Phosphorylation of Smad2, an effector of Ang II and TGF signaling, increased by 120% at week 7 and by 84% in response to intravenously infused Ang II. NADPH oxidase 4 (Nox4) mRNA expression, which is controlled by smad proteins, increased 430% at week 7, while Nox4 protein expression, which can activate Nrf2, was 170% higher at week 7 than at week 1. These results demonstrate that prolonged fasting activates Nrf2 in elephant seals and that RAS stimulation can potentially result in increased Nox4 through Smad phosphorylation. The results also suggest that Nox4 is essential to sustain the hormetic adaptive response to oxidative stress in fasting seals.

  18. Prolonged fatigue in Ukraine and the United States: Prevalence and risk factors

    PubMed Central

    Friedberg, Fred; Tintle, Nathan; Clark, Jake; Bromet, Evelyn J.

    2015-01-01

    Background Prolonged, severe, unalleviated fatigue may be disabling whether it occurs on its own or in conjunction with medical or psychiatric conditions. This paper compares the prevalence and correlates of prolonged fatigue in general population samples in Ukraine versus the U.S. Methods Population surveys were conducted in 2002 in both Ukraine (Ukraine World Mental Health [WMH] Survey) and the U.S. (National Comorbidity Survey-Replication; NCS-R). Both surveys administered the Composite International Diagnostic Interview (CIDI 3.0), which contained modules assessing: neurasthenia (prolonged fatigue); mood, anxiety, and alcohol/drug use disorders; chronic medical conditions; and demographic characteristics. Multivariable logistic regression was used to examine risk factors in each country. Results The lifetime prevalence of prolonged fatigue was higher in Ukraine (5.2%) than the U.S. (3.7%). In both countries, one-fifth of individuals with prolonged fatigue had no medical or DSM-IV psychiatric condition. Also in both settings, fatigue was significantly associated with sociodemographic characteristics (being female, not working, and married before) as well as early onset and adult episodes of mood/anxiety disorder. Fatigue prevalence in Ukraine increased with age, but decreased in the U.S. at age 70. Unique risk factors for fatigue in Ukraine included lower socio-economic status, Ukrainian vs Russian ethnicity, and cardiovascular disease. Unique risk factors in the U.S. were parental depression/anxiety, adult episodes of alcohol/drugs, pain conditions, and other health problems. Conclusions The lifetime prevalence of prolonged fatigue in Ukraine was 40% higher than that found in U.S. data. In addition, fatigue prevalence increased sharply with age in Ukraine perhaps due to limited social and medical resources and greater comorbidity. PMID:26807341

  19. Determinants of Prolonged Length of Stay in the Emergency Department; a Cross-sectional Study

    PubMed Central

    Hosseininejad, Seyed Mohammad; Aminiahidashti, Hamed; Pashaei, Seyede Masoume; Goli Khatir, Iraj; Montazer, Seyed Hosein; Bozorgi, Farzad; Mahmoudi, Fahime

    2017-01-01

    Introduction: Timeliness has been considered as a key domain in quality of emergency department (ED) care and delay in care providing is influential determinants of patient’s outcomes. The present study, aimed to evaluate the determinants of prolonged ED length of stay (LOS). Methods: In this cross-sectional study, using adopted version of the latest form for external evaluation and accreditation of EDs introduced by Iranian Ministry of Health, determinants of prolonged LOS were evaluated in the ED of an educational Hospital. Using SPSS 11, multivariate binary logistic regression was applied to estimate adjusted odds ratios (OR) for determining factors associated with prolonged LOS. Results: 162 (10.2%) cases with prolonged LOS were detected. Based on univariate analysis, female gender (OR: 1.42, 95% CI: 1.14-1.75, p = 0.001), older age (OR: 1.05, 95% CI: 1.02-1.08, p < 0.0001), admission on evening shifts (OR: 4.0; 95% CI: 1.84-8.68, p < 0.001), triage level I (OR: 1.76, 95% CI: 1.21-2.57, p = 0.003), lack of insurance support (OR: 1.56, 95% CI: 1.12-2.19, p = 0.010), higher number of ordered para-clinical tests (OR: 1.23, 95% CI: 1.11-1.37, p = 0.016), and disposition time > 6 hours (OR, 0.13, p < 0.0001), were significant risk factors of prolonged LOS. Conclusion Older age, lack of insurance support, disposition time > 6 hours due to complexity of patients’ complaint, and the necessity of repeated para-clinical measures were the most important reasons for failed provision of timely services. From the view point of ED personnel, a small part of prolonged LOS in ED was concerned with defective ED workflow, while, the most important cause of such delays was the delayed response of the consultancy services. PMID:28286860

  20. Marked QTc Prolongation and Torsades de pointes in Patients with Chronic Inflammatory Arthritis

    PubMed Central

    Lazzerini, Pietro Enea; Capecchi, Pier Leopoldo; Bertolozzi, Iacopo; Morozzi, Gabriella; Lorenzini, Sauro; Simpatico, Antonella; Selvi, Enrico; Bacarelli, Maria Romana; Acampa, Maurizio; Lazaro, Deana; El-Sherif, Nabil; Boutjdir, Mohamed; Laghi-Pasini, Franco

    2016-01-01

    Mounting evidence indicates that in chronic inflammatory arthritis (CIA), QTc prolongation is frequent and correlates with systemic inflammatory activation. Notably, basic studies demonstrated that inflammatory cytokines induce profound changes in potassium and calcium channels resulting in a prolonging effect on cardiomyocyte action potential duration, thus on the QT interval on the electrocardiogram. Moreover, it has been demonstrated that in rheumatoid arthritis (RA) patients, the risk of sudden cardiac death is significantly increased when compared to non-RA subjects. Conversely, to date no data are available about torsades de pointes (TdP) prevalence in CIA, and the few cases reported considered CIA only an incidental concomitant disease, not contributing factor to TdP development. We report three patients with active CIA developing marked QTc prolongation, in two cases complicated with TdP degenerating to cardiac arrest. In these patients, a blood sample was obtained within 24 h from TdP/marked QTc prolongation occurrence, and levels of IL-6, TNFα, and IL-1 were evaluated. In all three cases, IL-6 was markedly elevated, ~10 to 100 times more than reference values. Moreover, one patient also showed high circulating levels of TNFα and IL-1. In conclusion, active CIA may represent a currently overlooked QT-prolonging risk factor, potentially contributing in the presence of other “classical” risk factors to TdP occurrence. In particular, a relevant role may be played by elevated circulating IL-6 levels via direct electrophysiological effects on the heart. This fact should be carefully kept in mind, particularly when recognizable risk factors are already present and/or the addition of QT-prolonging drugs is required. PMID:27703966

  1. Identifying the translational gap in the evaluation of drug-induced QTc interval prolongation

    PubMed Central

    Chain, Anne SY; Dubois, Vincent FS; Danhof, Meindert; Sturkenboom, Miriam CJM; Della Pasqua, Oscar

    2013-01-01

    Aims Given the similarities in QTc response between dogs and humans, dogs are used in pre-clinical cardiovascular safety studies. The objective of our investigation was to characterize the PKPD relationships and identify translational gaps across species following the administration of three compounds known to cause QTc interval prolongation, namely cisapride, d, l-sotalol and moxifloxacin. Methods Pharmacokinetic and pharmacodynamic data from experiments in conscious dogs and clinical trials were included in this analysis. First, pharmacokinetic modelling and deconvolution methods were applied to derive drug concentrations at the time of each QT measurement. A Bayesian PKPD model was then used to describe QT prolongation, allowing discrimination of drug-specific effects from other physiological factors known to alter QT interval duration. A threshold of ≥10 ms was used to explore the probability of prolongation after drug administration. Results A linear relationship was found to best describe the pro-arrhythmic effects of cisapride, d,l-sotalol and moxifloxacin both in dogs and in humans. The drug-specific parameter (slope) in dogs was statistically significantly different from humans. Despite such differences, our results show that the probability of QTc prolongation ≥10 ms in dogs nears 100% for all three compounds at the therapeutic exposure range in humans. Conclusions Our findings indicate that the slope of PKPD relationship in conscious dogs may be used as the basis for the prediction of drug-induced QTc prolongation in humans. Furthermore, the risk of QTc prolongation can be expressed in terms of the probability associated with an increase ≥10 ms, allowing direct inferences about the clinical relevance of the pro-arrhythmic potential of a molecule. PMID:23351036

  2. Associations between prolonged sedentary time and breaks in sedentary time with cardiometabolic risk in 10-14-year-old children: The HAPPY study.

    PubMed

    Bailey, Daniel P; Charman, Sarah J; Ploetz, Thomas; Savory, Louise A; Kerr, Catherine J

    2016-11-28

    This study examines the association between prolonged sedentary time and breaks in sedentary time with cardiometabolic risk in 10-14-year-old children. This cross-sectional design study analysed accelerometry-determined sedentary behaviour and physical activity collected over 7 days from 111 (66 girls) UK schoolchildren. Objective outcome measures included waist circumference, fasting lipids, fasting glucose, blood pressure, and cardiorespiratory fitness. Logistic regression was used for the main data analysis. After adjustment for confounders, the odds of having hypertriglyceridaemia (P = 0.03) and an increased clustered cardiometabolic risk score (P = 0.05) were significantly higher in children who engaged in more prolonged sedentary bouts per day. The number of breaks in sedentary time per day was not associated with any cardiometabolic risk factor, but longer mean duration of daily breaks in sedentary time were associated with a lower odds of having abdominal adiposity (P = 0.04) and elevated diastolic blood pressure (P = 0.01). These associations may be mediated by engagement in light activity. This study provides evidence that avoiding periods of prolonged uninterrupted sedentary time may be important for reducing cardiometabolic disease risk in children.

  3. Transient simulation of coolant peak temperature due to prolonged fan and/or water pump operation after the vehicle is keyed-off

    NASA Astrophysics Data System (ADS)

    Pang, Suh Chyn; Masjuki, Haji Hassan; Kalam, Md. Abul; Hazrat, Md. Ali

    2014-01-01

    Automotive designers should design a robust engine cooling system which works well in both normal and severe driving conditions. When vehicles are keyed-off suddenly after some distance of hill-climbing driving, the coolant temperature tends to increase drastically. This is because heat soak in the engine could not be transferred away in a timely manner, as both the water pump and cooling fan stop working after the vehicle is keyed-off. In this research, we aimed to visualize the coolant temperature trend over time before and after the vehicles were keyed-off. In order to prevent coolant temperature from exceeding its boiling point and jeopardizing engine life, a numerical model was further tested with prolonged fan and/or water pump operation after keying-off. One dimensional thermal-fluid simulation was exploited to model the vehicle's cooling system. The behaviour of engine heat, air flow, and coolant flow over time were varied to observe the corresponding transient coolant temperatures. The robustness of this model was proven by validation with industry field test data. The numerical results provided sensible insights into the proposed solution. In short, prolonging fan operation for 500 s and prolonging both fan and water pump operation for 300 s could reduce coolant peak temperature efficiently. The physical implementation plan and benefits yielded from implementation of the electrical fan and electrical water pump are discussed.

  4. The physiological consequences of varied heat exposure events in adult Myzus persicae: a single prolonged exposure compared to repeated shorter exposures

    PubMed Central

    Andrew, Nigel R.

    2016-01-01

    The study of environmental stress tolerance in aphids has primarily been at low temperatures. In these cases, and in the rare cases of high temperature tolerance assessments, all exposures had been during a single stress event. In the present study, we examined the physiological consequences of repeated high temperature exposure with recovery periods between these stress events in Myzus persicae. We subjected individuals to either a single prolonged three hour heating event, or three one hour heating events with a recovery time of 24 h between bouts. Aphids exposed to repeated bouts of high temperatures had more glucose and higher expression of proteins and osmolyte compounds, such as glycerol, compared to the prolonged exposure group. However, aphids exposed to the repeated high temperature treatment had reduced sources of energy such as trehalose and triglyceride compounds than the prolonged exposure group. Recovery time had more physiological costs (based on production of more protein and consumption of more trehalose and triglyceride) and benefits (based on production of more osmolytes) in repeated high temperature treatments. As aphids are known to respond differently to constant versus ‘natural’ fluctuating temperature regimes, conclusions drawn from constant temperature data sets may be problematic. We suggest future experiments assessing insect responses to thermal stress incorporate a repeated stress and recovery pattern into their methodologies. PMID:27547583

  5. The Impact of Prolonged Economic Downturns and Economic Crises on the Nursing Profession.

    PubMed

    Phua, Kai-Lit; Hue, Jia-Wern

    2015-01-01

    Prolonged economic downturns and economic crises are affecting nations around the world, including developed countries such as Portugal, Spain, and Greece. In the United States, recovery from the latest economic crisis has been accompanied by a persistently high rate of unemployment. To a large extent, the impacts on the nursing profession may depend on the severity of economic downturns and their duration in the country of employment of nurses. Nurses in certain areas of patient care (such as mental health) may also be more strongly affected because of the impact of economic crises and high unemployment on morbidity patterns. Emigration of nurses may also increase as a result of prolonged economic crisis.

  6. Kerato-lenticular ocular deposits and visual impairment with prolonged chlorpromazine use: A case series.

    PubMed

    Gowda, Guru S; Hegde, Aditya; Shanbhag, Vandita; Narayanaswamy, Janardhanan C; Jaisoorya, T S

    2017-02-01

    Chlorpromazine is a low potency "typical" antipsychotic agent used to treat schizophrenia. It continues to be prescribed frequently in India owing to its lower cost. There have been previous reports of ocular adverse effects with prolonged use of chlorpromazine. We report three patients who developed corneal and lenticular opacities secondary to prolonged chlorpromazine use leading to visual impairment. Early detection of ocular deposits and switching over to risperidone from chlorpromazine helped in the reversal of chlorpromazine- induced ocular side effects in one of them. The case series further adds evidence to the causative relationship between chlorpromazine and ocular side effects.

  7. Prolonged duodenal paralysis after PEG placement in a patient with traumatic brain injury: a case report.

    PubMed

    Mammi, P; Zaccaria, B; Dazzi, F; Saccavini, M

    2011-03-01

    Percutaneous endoscopic gastrostomy (PEG) has recently become a usual procedure for patients with prolonged disorders of consciousness after brain injuries. Despite a high rate of success and a very low procedure-related mortality, morbidity associated to PEG placement reaches 9.4% in a recent large meta-analysis. This case report describes an uncommon complication of PEG placement in a patient with vegetative state after traumatic brain injury: the development of prolonged duodenal paralysis. This patient was treated by placement of a transient jejunostomy until recovery of duodenal functional activity, to permit adequate nutrition. This procedure-related complication is previously unreported in scientific literature.

  8. The effect of neutrophil migration and prolonged neutrophil contact on epithelial permeability.

    PubMed Central

    Parsons, P. E.; Sugahara, K.; Cott, G. R.; Mason, R. J.; Henson, P. M.

    1987-01-01

    The effect of neutrophil migration and prolonged neutrophil contact on epithelial permeability was examined. Although neutrophil migration was not associated with a change in epithelial permeability, prolonged neutrophil-epithelial contact following migration resulted in an increase in epithelial permeability. These results were not altered by catalase, a specific neutrophil elastase inhibitor, methoxysuccinyl-Ala-Ala-Pro-Val-chloromethyl ketone or cyclohexamide. This suggests that neutrophil migration does not occur via an H2O2-induced reversible mechanism of junctional opening, which we describe herein. PMID:3314530

  9. [Therapeutic effects of prolonged normovolemic hemodilution in patients with Raynaud's disease].

    PubMed

    Mamurov, V A

    1998-01-01

    51 patients with Raynaud's disease has undergone prolonged normovolemic hemodilution (PNH) with a good effect. Disappearance of painful syndrome in 78.43% of cases, and a significant decrease of pains in 21.37% of cases was demonstrated. Complete healing of ulcero-necrotic defects of end phalanges of the hands was observed in 7 patients of 10 and partial--in 3. A significant remission of the disease in follow-up period was obtained. Thus, prolonged normovolemic hemodilution has resulted in significant improvement of short- and long-term results of treatment in patients with Raynaud's disease.

  10. Green teeth are a late complication of prolonged conjugated hyperbilirubinemia in extremely low birth weight infants.

    PubMed

    Battineni, Sireesha; Clarke, Paul

    2012-01-01

    Eruption of green, discolored teeth affecting the primary dentition has been described in association with congenital viral infection, sepsis, hemolytic jaundice, and cholestasis. The purpose of this paper was to present the cases of 3 extremely low birth weight preterm infants who were noted to have green teeth at the corrected ages of 10 to 12 months. All had a history of prolonged conjugated hyperbilirubinemia during their time in neonatal intensive care. For infants with prolonged conjugated hyperbilirubinemia, extreme preterm birth and/or extremely low birth weight may be additional risk factors predisposing to the eruption of green teeth in later infancy.

  11. Effect of prolonged bed rest on lung volume in normal individuals

    NASA Technical Reports Server (NTRS)

    Beckett, W. S.; Vroman, N. B.; Nigro, D.; Thompson-Gorman, S.; Wilkerson, J. E.

    1986-01-01

    The effect of prolonged bed rest on the lung function was studied by measuring forced vital capacity (FVC) and total lung capacity (TLC) in normal subjects before, during, and after 11- to 12-day rest periods. It was found that both FVC and TLC increased during bed rest (compared with the ambulatory controls), while residual volume and functional residual capacity of the respiratory system did not change. It is concluded that the increase in TLC by prolonged bed rest is not dependent on alterations in plasma volume.

  12. Effect of the Volume of Fluid Ingested on Urine Concentrating Ability During Prolonged Heavy Exercise in a Hot Environment

    PubMed Central

    Otani, Hidenori; Kaya, Mitsuharu; Tsujita, Junzo

    2013-01-01

    This study examined the effect of the volume of fluid ingested on urine concentrating ability during prolonged heavy exercise in a hot environment at low levels of dehydration. Seven healthy males performed 105 min of intermittent cycle exercise at 70% maximum oxygen uptake (32°C, 60% relative humidity) while receiving no fluid ingestion (NF), voluntary fluid ingestion (VF), partial fluid ingestion equivalent to one-half of body mass loss (PF), and full fluid ingestion equivalent to body mass loss (FF). Fluid (5°C, 3.4% carbohydrate, 10.5 mmol·L-1 sodium) was ingested just before commencing exercise and at 15, 33, 51, 69, and 87 min of exercise, and the total amount of fluid ingested in PF and FF was divided into six equal volumes. During exercise, body mass loss was 2.2 ± 0.2, 1.1 ± 0.5, 1.1 ± 0.2, and 0.1 ± 0.2% in NF, VF, PF, and FF, respectively, whereas total sweat loss was about 2% of body mass in each trial. Subjects in VF ingested 719 ± 240 ml of fluid during exercise; the volume of fluid ingested was 1.1 ± 0.4% of body mass. Creatinine clearance was significantly higher and free water clearance was significantly lower in FF than in NF during exercise. Urine flow rate during exercise decreased significantly in NF. There were significant decreases in creatinine and osmolar clearance and was a significant increase in free water clearance during exercise in NF and VF. Creatinine clearance decreased significantly and free water clearance increased significantly during exercise in PF. There was no statistical change in urinary indices of renal function during exercise in FF. The findings suggest that full fluid ingestion equivalent to body mass loss has attenuated the decline in urine concentrating ability during prolonged heavy exercise in a hot environment at low levels of dehydration. Key points During prolonged heavy exercise in a hot environment at low levels of dehydration, fluid ingestion equivalent to body mass loss results in no changes in

  13. Ventricular arrhythmia incidence in the rat is reduced by naloxone.

    PubMed

    Pugsley, M K; Hayes, E S; Wang, W Q; Walker, M J A

    2015-07-01

    This study characterized the antiarrhythmic effects of the opioid receptor antagonist naloxone in rats subject to electrically induced and ischemic arrhythmias. Naloxone (2, 8 and 32 μmol/kg/min) was examined on heart rate, blood pressure, and the electrocardiogram (EKG) as well as for effectiveness against arrhythmias produced by occlusion of the left anterior descending coronary artery or electrical stimulation of the left ventricle. Naloxone reduced blood pressure at the highest dose tested while heart rate was dose-dependently reduced. Naloxone dose-dependently prolonged the P-R and QRS intervals and increased the RSh amplitude indicative of effects on cardiac sodium (Na) channels. Naloxone prolonged the Q-T interval suggesting a delay in repolarization. Naloxone effects were comparable to the comparator quinidine. Naloxone (32 μmol/kg/min) reduced ventricular fibrillation (VF) incidence to 38% (from 100% in controls). This same dose significantly increased the threshold for induction of ventricular fibrillation (VFt), prolonged the effective refractory period (ERP) and reduced the maximal following frequency (MFF). The patterns of ECG changes, reduction in ischemic arrhythmia (VF) incidence and changes in electrically induced arrhythmia parameters at high doses of naloxone suggest that it directly blocks cardiac Na and potassium (K) ion channels.

  14. The combination of short rest and energy drink consumption as fatigue countermeasures during a prolonged drive of professional truck drivers.

    PubMed

    Ronen, Adi; Oron-Gilad, Tal; Gershon, Pnina

    2014-06-01

    One of the major concerns for professional drivers is fatigue. Many studies evaluated specific fatigue countermeasures, in many cases comparing the efficiency of each method separately. The present study evaluated the effectiveness of rest areas combined with consumption of energy drinks on professional truck drivers during a prolonged simulated drive. Fifteen professional truck drivers participated in three experimental sessions: control-drivers were asked to drink 500 ml of a placebo drink prior to the beginning of the drive. Energy drink-drivers were asked to drink 500 ml of an energy drink containing 160 mg of caffeine prior to the beginning of the drive, and an Energy drink+Rest session--where the drivers were asked to drink 500 ml of an energy drink prior to driving, and rest for 10 min at a designated rest area zone 100 min into the drive. For all sessions, driving duration was approximately 150 min and consisted of driving on a monotonous, two-way rural road. In addition to driving performance measures, subjective measures, and heart rate variability were obtained. Results indicated that consumption of an energy drink (in both sessions) facilitated lower lane position deviations and reduced steering wheel deviations during the first 80-100 min of the drive relative to the control sessions. Resting after 100 min of driving, in addition to the energy drink that was consumed before the drive, enabled the drivers to maintain these abilities throughout the remainder of the driving session. Practical applications: Practical applications arising from the results of this research may give indication on the possible added value of combining fatigue counter measures methods during a prolonged drive and the importance of the timing of the use for each method.

  15. CXCR3 Antagonism Impairs the Development of Donor-reactive, IFN-γ-producing Effectors and Prolongs Allograft Survival 1

    PubMed Central

    Rosenblum, J.M.; Zhang, Q-W.; Siu, G.; Collins, T. L.; Sullivan, T.; Dairaghi, D.J.; Medina, J.C.; Fairchild, R.L.

    2009-01-01

    Background Current immunosuppression regimens are highly toxic to transplant recipients and, in many cases, acute rejection episodes occur due to escape of donor-reactive lymphocytes from the immunosuppression. T cells are the mediators of acute, cell-mediated graft damage and are hypothesized to use the CXCR3 chemokine axis for migration into the allograft. In the current study, we investigated the effect of CXCR3 blockade using a non-peptide, small molecule inhibitor, AMG1237845, in murine cardiac allograft survival. Methods C57BL/6 (H-2b) mice received vascularized cardiac allografts from A/J (H-2a) donors and were treated with the CXCR3 antagonist. Histological and flow cytometric analyses were used to measure infiltration of leukocytes, and qRT-PCR and IFN-γ ELISPOT assays were used to measure donor-specific reactivity. Results CXCR3 antagonism modestly prolonged allograft survival compared to vehicle treatment, but at time-matched intervals post-transplant, neutrophil, CD8+, and CD4+ T cell infiltration was indistinguishable. While proliferation of donor-reactive naïve T cells was unaffected by CXCR3 antagonism, the frequency of IFN-γ-producing cells in the recipient spleen was significantly reduced by AMG1237845 treatment. CXCR3 blockade for 30 days synergized with short-term, low-dose anti-CD154 mAb to prolong survival past 50 days in 75% of grafts and past 80 days in 25% of the cases. Conclusions These results indicate that in synergy with co-stimulation blockade, CXCR3 is a viable therapeutic target to prevent acute graft rejection. PMID:19202440

  16. Effects of worn-out soles on lower limb stability, shock absorption and energy cost during prolonged walking.

    PubMed

    Saito, Seiji; Muraki, Satoshi; Tochihara, Yutaka

    2007-09-01

    This study investigated the effects of worn-out shoes on lower leg stability, shock absorption and energy cost during prolonged walking. Seven male subjects (23.4 +/- 0.5 yr) walked at 4.8 km/h for 60 minutes wearing three different pairs of shoes: two of these pairs had severely and moderately worn soles (EASC: Excessive Attrite Shoe Condition and MASC: Moderate Attrite Shoe Condition, respectively) and the other pair had no wear (NASC: No Attrite Shoe Condition). Impact acceleration at the subtalar at heel strike, rearfoot angles (the subtalar joint and the lower leg) during stance phase, and oxygen uptake (VO2) were measured throughout the 60-minute walk. At the 10th minute of walking, worn-out shoes increased the supination of the subtalar joint and extortion of the lower leg. In addition, VO2 was significant larger in EASC (808.3 ml x min(-1)) than in NASC (749.5 ml x min(-1)). During the 60-minute walk, however, there were no time effects of shoe condition on the rearfoot angles and on VO2. In contrast, impact acceleration at the subtalar joint in EASC remained almost constant until the 30th minute of walking, and then began to elevate. In conclusion, worn-out shoes increased the energy cost and reduced lower leg stability during walking, although these changes were not influenced by walking duration within 60 minutes. However, prolonged walking showed the potential negative effect of worn-out shoe on shock absorption.

  17. Efficacy of Liposomal Amphotericin B with Prolonged Circulation in Blood in Treatment of Severe Pulmonary Aspergillosis in Leukopenic Rats

    PubMed Central

    Van Etten, Els W. M.; Stearne-Cullen, Lorna E. T.; Ten Kate, Marian T.; Bakker-Woudenberg, Irma A. J. M.

    2000-01-01

    The therapeutic efficacy of long-circulating polyethylene glycol-coated liposomal amphotericin B (AMB) (PEG-AMB-LIP) was compared with that of AMB desoxycholate (Fungizone) in a model of severe invasive pulmonary aspergillosis in persistently leukopenic rats as well as in temporarily leukopenic rats. PEG-AMB-LIP treatment (intravenous administration) consisted of a single, or double (every 72 h), or triple (every 72 h) dose of 10 mg of AMB/kg of body weight, a double dose (every 72 h) of 14 mg of AMB/kg, or a 5-day treatment (every 24 h) with 6 mg/kg/dose. AMB desoxycholate was administered for 10 consecutive days at 1 mg of AMB/kg/dose. Treatment was started 30 h after fungal inoculation, at which time mycelial growth was firmly established. Both persistently and temporarily leukopenic rats died between 4 and 9 days after Aspergillus fumigatus inoculation when they were left untreated or after treatment with a placebo. In persistently leukopenic rats, a single dose of PEG-AMB-LIP (10 mg/kg) was as effective as the 10-day treatment with AMB desoxycholate (at 1 mg/kg/dose) in significantly prolonging the survival of rats infected with A. fumigatus and in reducing the dissemination of A. fumigatus to the liver. Prolongation of PEG-AMB-LIP treatment (double or triple dose or 5-day treatment) did not further improve efficacy. For temporarily leukopenic rats no major advances in efficacy were achieved compared to those for persistently leukopenic rats, probably because the leukocyte numbers in blood were restored too late in the course of infection. PMID:10681315

  18. Linguistic and Psychological Perspectives on Prolonged Periods of Silence in Dual-Language Learners

    ERIC Educational Resources Information Center

    Le Pichon, Emmanuelle; de Jonge, Maretha

    2016-01-01

    In this paper, we present an examination of the literature on prolonged periods of silence in children from the perspective of two different scientific fields. The aim is to call attention to the inherent complexity of the factors that may be involved in the etiology of mutistic behavior during child development. Medical and linguistic literature…

  19. Prolonged survival of a cat diagnosed with feline infectious peritonitis by immunohistochemistry.

    PubMed

    Hugo, Timothy B; Heading, Kathryn L

    2015-01-01

    A 4-year-old, neutered male, British shorthair cat was presented with inappetence, vomiting, hyperproteinemia, and hyperglobulinemia. An exploratory celiotomy identified enlarged mesenteric lymph nodes. Immunohistochemistry of lymph node biopsies confirmed feline infectious peritonitis. This patient had a prolonged survival of 787 d after initial presentation.

  20. Prolonged leucine infusion differentially affects tissue protein synthesis in neonatal pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leucine (Leu) acutely stimulates protein synthesis by activating the mammalian target of rapamycin complex 1 (mTORC1) pathway. To determine whether Leu can stimulate protein synthesis in muscles of different fiber types and visceral tissues of the neonate for a prolonged period and to determine the ...

  1. Uremic retention solute indoxyl sulfate level is associated with prolonged QTc interval in early CKD patients.

    PubMed

    Tang, Wei-Hua; Wang, Chao-Ping; Chung, Fu-Mei; Huang, Lynn L H; Yu, Teng-Hung; Hung, Wei-Chin; Lu, Li-Fen; Chen, Po-Yuan; Luo, Ching-Hsing; Lee, Kun-Tai; Lee, Yau-Jiunn; Lai, Wen-Ter

    2015-01-01

    Total mortality and sudden cardiac death is highly prevalent in patients with chronic kidney disease (CKD). In CKD patients, the protein-bound uremic retention solute indoxyl sulfate (IS) is independently associated with cardiovascular disease. However, the underlying mechanisms of this association have yet to be elucidated. The relationship between IS and cardiac electrocardiographic parameters was investigated in a prospective observational study among early CKD patients. IS arrhythmogenic effect was evaluated by in vitro cardiomyocyte electrophysiological study and mathematical computer simulation. In a cohort of 100 early CKD patients, patients with corrected QT (QTc) prolongation had higher IS levels. Furthermore, serum IS level was independently associated with prolonged QTc interval. In vitro, the delay rectifier potassium current (IK) was found to be significantly decreased after the treatment of IS in a dose-dependent manner. The modulation of IS to the IK was through the regulation of the major potassium ion channel protein Kv 2.1 phosphorylation. In a computer simulation, the decrease of IK by IS could prolong the action potential duration (APD) and induce early afterdepolarization, which is known to be a trigger mechanism of lethal ventricular arrhythmias. In conclusion, serum IS level is independently associated with the prolonged QTc interval in early CKD patients. IS down-regulated IK channel protein phosphorylation and the IK current activity that in turn increased the cardiomyocyte APD and QTc interval in vitro and in the computer ORd model. These findings suggest that IS may play a role in the development of arrhythmogenesis in CKD patients.

  2. Long-term outcome and safety of prolonged bedaquiline treatment for multidrug-resistant tuberculosis.

    PubMed

    Guglielmetti, Lorenzo; Jaspard, Marie; Le Dû, Damien; Lachâtre, Marie; Marigot-Outtandy, Dhiba; Bernard, Christine; Veziris, Nicolas; Robert, Jérôme; Yazdanpanah, Yazdan; Caumes, Eric; Fréchet-Jachym, Mathilde

    2017-03-01

    Bedaquiline, a recently approved drug for the treatment of multidrug-resistant tuberculosis (MDR-TB), is recommended for a duration of 24 weeks. There are scarce data on patients treated with this drug outside clinical trials.All MDR-TB patients who started treatment from January 1, 2011 to December 31, 2013 and received ≥30 days of bedaquiline were included in a multicentre observational cohort.Among 45 MDR-TB patients, 53% harboured isolates resistant to both fluoroquinolones and second-line injectables, and 38% harboured isolates resistant to one of these drug classes. Median bedaquiline treatment duration was 361 days and 33 patients (73%) received prolonged (>190 days) bedaquiline treatment. Overall, 36 patients (80%) had favourable outcome, five were lost to follow-up, three died, and one failed and acquired bedaquiline resistance. No cases of recurrence were reported. Severe and serious adverse events were recorded in 60% and 18% of patients, respectively. Values of Fridericia-corrected QT interval (QTcF) >500 ms were recorded in 11% of patients, but neither arrhythmias nor symptomatic cardiac side-effects occurred. Bedaquiline was discontinued in three patients following QTcF prolongation. No significant differences in outcomes or adverse events rates were observed between patients receiving standard and prolonged bedaquiline treatment.Bedaquiline-containing regimens achieved favourable outcomes in a large proportion of patients. Prolonged bedaquiline treatment was overall well tolerated in this cohort.

  3. Sudden Gains in Prolonged Exposure for Children and Adolescents with Posttraumatic Stress Disorder

    ERIC Educational Resources Information Center

    Aderka, Idan M.; Appelbaum-Namdar, Edna; Shafran, Naama; Gilboa-Schechtman, Eva

    2011-01-01

    Objective: Our objective was to examine sudden gains during developmentally adjusted prolonged exposure for posttraumatic stress disorder (PTSD) among children and adolescents. We hypothesized that sudden gains would be detected and would be predictive of treatment outcome and follow-up. Method: Sixty-three youngsters (ages 8-17) completed a…

  4. Prolonged Exposure versus Dynamic Therapy for Adolescent PTSD: A Pilot Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Gilboa-Schechtman, Eva; Foa, Edna B.; Shafran, Naama; Aderka, Idan M.; Powers, Mark B.; Rachamim, Lilach; Rosenbach, Lea; Yadin, Elna; Apter, Alan

    2010-01-01

    Objective: To examine the efficacy and maintenance of developmentally adapted prolonged exposure therapy for adolescents (PE-A) compared with active control time-limited dynamic therapy (TLDP-A) for decreasing posttraumatic and depressive symptoms in adolescent victims of single-event traumas. Method: Thirty-eight adolescents (12 to 18 years old)…

  5. Artifactual prolongation of activated partial thromboplastin time with PEGylated compounds in silica-based assays.

    PubMed

    Murphy, Bethanne; Parrula, Maria C M; Perigard, Christopher J; Li, Jinze

    2014-12-01

    Conjugation of polyethylene glycol (PEG) to another molecule prolongs its half-life in the body, but has a potential to artifactually increase the activated partial thromboplastin time (aPTT) as measured with certain assays. Studies conducted in-house at Bristol-Myers Squibb using the STA-PTT Automate 5 assay, the routine assay used to measure aPTT, demonstrated prolongation of aPTT in plasma samples spiked in vitro with 40-kDa branched PEG (PEG40) conjugated compounds or PEG40 alone, but not in samples spiked with vehicle or non-PEGylated compound, suggesting that the interference is because of the PEG40 moiety. To investigate the cause of this phenomenon, cynomolgus monkey and rat plasma samples were spiked with different concentrations of PEG40 and the aPTT was measured using different proprietary assays. With one exception, prolongation of aPTT was observed with all assays containing silica as the contact activator. No changes in aPTT were noted in assays using kaolin as a contact activator. The findings indicated that the observed prolongation of aPTT is largely because of interference of PEG40 with the silica, but other features of the reagent mixture may also influence aPTT times.

  6. Does Prolonged Therapy with a Long-Acting Stimulant Suppress Growth in Children with ADHD?

    ERIC Educational Resources Information Center

    Spencer, Thomas J.; Faraone, Stephen V.; Biederman, Joseph; Lerner, Marc; Cooper, Kimberly M.; Zimmerman, Brenda

    2006-01-01

    Objective: To investigate whether prolonged therapy with a long-acting stimulant affects growth in children with attention-deficit/hyperactivity disorder (ADHD). Method: One hundred seventy-eight children ages 6 to 13 years received OROS methylphenidate (OROS MPH, CONCERTA) for at least 21 months. Height and weight were measured monthly during the…

  7. The promoter of the cereal VERNALIZATION1 gene is sufficient for transcriptional induction by prolonged cold.

    PubMed

    Alonso-Peral, Maria M; Oliver, Sandra N; Casao, M Cristina; Greenup, Aaron A; Trevaskis, Ben

    2011-01-01

    The VERNALIZATION1 (VRN1) gene of temperate cereals is transcriptionally activated by prolonged cold during winter (vernalization) to promote flowering. To investigate the mechanisms controlling induction of VRN1 by prolonged cold, different regions of the VRN1 gene were fused to the GREEN FLUORESCENT PROTEIN (GFP) reporter and expression of the resulting gene constructs was assayed in transgenic barley (Hordeum vulgare). A 2 kb segment of the promoter of VRN1 was sufficient for GFP expression in the leaves and shoot apex of transgenic barley plants. Fluorescence increased at the shoot apex prior to inflorescence initiation and was subsequently maintained in the developing inflorescence. The promoter was also sufficient for low-temperature induction of GFP expression. A naturally occurring insertion in the proximal promoter, which is associated with elevated VRN1 expression and early flowering in some spring wheats, did not abolish induction of VRN1 transcription by prolonged cold, however. A translational fusion of the promoter and transcribed regions of VRN1 to GFP, VRN1::GFP, was localised to nuclei of cells at the shoot apex of transgenic barley plants. The distribution of VRN1::GFP at the shoot apex was similar to the expression pattern of the VRN1 promoter-GFP reporter gene. Fluorescence from the VRN1::GFP fusion protein increased in the developing leaves after prolonged cold treatment. These observations suggest that the promoter of VRN1 is targeted by mechanisms that trigger vernalization-induced flowering in economically important temperate cereal crops.

  8. Prolonged Detection of Zika Virus in Vaginal Secretions and Whole Blood

    PubMed Central

    Gorchakov, Rodion; Carlson, Anna R.; Berry, Rebecca; Lai, Lilin; Natrajan, Muktha; Garcia, Melissa N.; Correa, Armando; Patel, Shital M.; Aagaard, Kjersti; Mulligan, Mark J.

    2017-01-01

    Infection with Zika virus is an emerging public health crisis. We observed prolonged detection of virus RNA in vaginal mucosal swab specimens and whole blood for a US traveler with acute Zika virus infection who had visited Honduras. These findings advance understanding of Zika virus infection and provide data for additional testing strategies. PMID:27748649

  9. Prolong Restoration of the Water Quality of River Ganga Effect of Heavy Metals and Radioactive Elements.

    PubMed

    Tare, Vinod; Basu, Subhankar

    2014-04-01

    The genesis of the present research was the belief since ages and the observations made through some studies that the water of river Ganga has unique characteristics, which allows storage of water quality even on prolong storage. Very few systematic studies have been conducted to support the contention that the Ganga water indeed has some special composition that could be attributed to its unique storage capacity. It was postulated that prolong restoration of water quality depends on the ability to arrest microbial activity that is generally responsible for deterioration in water quality on prolong storage. Hence, attempt has been made to identify the parameters that are likely to influence the prolong storage of river water. Along with Ganga river water, other three major rivers, viz. Yamuna, Godavari and Narmada, were selected for comparison. Emphasis was made on estimation of heavy metals, radioactive elements, dissolved carbon and other physicochemical parameters such as temperature, pH, alkalinity, hardness and dissolved organic carbon. Based on the available information regarding the impact of heavy metals, radioactive elements vis-à-vis the chemical composition of water on microorganisms in the aquatic environment, an overall impact score for the waters of the four Indian rivers selected in the study has been assigned.

  10. Impact of Father Absence: III. Problems of Family Reintegrating Following Prolonged Father Absence.

    ERIC Educational Resources Information Center

    Baker, Stewart L.; and others

    A three-phase, longitudinal study at Walter Reed Hospital in Washington, D.C., of family problems with prolonged father absence indicates that there is (1) continuing family growth beyond the situational crisis, (2) active re-examination of roles and values, and (3) heightened awareness of family strength and resourcefulness during the…

  11. Prolonged neuropsychiatric effects following management of chloroquine intoxication with psychotropic polypharmacy

    PubMed Central

    Maxwell, Nicole M; Nevin, Remington L; Stahl, Stephen; Block, Jerald; Shugarts, Sarah; Wu, Alan H B; Dominy, Stephen; Solano-Blanco, Miguel Alonso; Kappelman-Culver, Sharon; Lee-Messer, Christopher; Maldonado, Jose; Maxwell, Andrew J

    2015-01-01

    Key Clinical Message Susceptibility to quinoline antimalarial intoxication may reflect individual genetic and drug-induced variation in neuropharmacokinetics. In this report, we describe a case of chloroquine intoxication that appeared to be prolonged by subsequent use of multiple psychotropic medications. This case highlights important new considerations for the management of quinoline antimalarial intoxication. PMID:26185633

  12. Serum and CSF levels of cytokines in acute encephalopathy following prolonged febrile seizures.

    PubMed

    Ichiyama, Takashi; Suenaga, Naoko; Kajimoto, Madoka; Tohyama, Jun; Isumi, Hiroshi; Kubota, Masaya; Mori, Masato; Furukawa, Susumu

    2008-01-01

    It is well known that an acute encephalopathy occasionally follows prolonged febrile seizures. We measured the concentrations of interferon-gamma, tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), IL-4, IL-6, IL-10, and soluble TNF receptor 1 (sTNFR1) in serum and CSF during the acute stage in 13 children with acute encephalopathy following prolonged febrile seizures (AEPFS) and 23 with prolonged febrile seizures without encephalopathy (PFS) to investigate the pathogenesis of AEPFS. Serum IL-6, IL-10, sTNFR1, and CSF IL-6 levels were significantly higher in AEPFS and PFS compared with control subjects. CSF IL-6 levels in AEPFS were significantly higher than those in PFS, but not serum IL-6, IL-10, or sTNFR1. The CSF IL-6 levels were significantly higher than the serum levels in AEPFS, but not PFS. The serum levels of sTNFR1 and IL-10 were significantly higher than those in the CSF in AEPFS and PFS. The serum IL-10 and sTNFR1 levels in patients who did not experience a second seizure were significantly higher than those in patients who experienced a second seizure, which was characterized by clusters of complex partial seizures several days after the initial prolonged febrile seizure. Our results suggest that serum IL-6, IL-10, TNF-alpha, and CSF IL-6 are part of the regulatory system of cytokines in AEPFS.

  13. Prolonged survival of a cat diagnosed with feline infectious peritonitis by immunohistochemistry

    PubMed Central

    Hugo, Timothy B.; Heading, Kathryn L.

    2015-01-01

    A 4-year-old, neutered male, British shorthair cat was presented with inappetence, vomiting, hyperproteinemia, and hyperglobulinemia. An exploratory celiotomy identified enlarged mesenteric lymph nodes. Immunohistochemistry of lymph node biopsies confirmed feline infectious peritonitis. This patient had a prolonged survival of 787 d after initial presentation. PMID:25565715

  14. Effect of blood volume in resting muscle on heart rate upward drift during moderately prolonged exercise.

    PubMed

    Kimura, Takehide; Matsuura, Ryouta; Arimitsu, Takuma; Yunoki, Takahiro; Yano, Tokuo

    2010-01-01

    The aim of this study was to determine whether the increase in blood volume in resting muscle during moderately prolonged exercise is related to heart rate (HR) upward drift. Eight healthy men completed both arm-cranking moderately prolonged exercise (APE) and leg-pedaling moderately prolonged exercise (LPE) for 30 min. Exercise intensity was 120 bpm of HR that was determined by ramp incremental exercise. During both APE and LPE, HR significantly increased from 3 to 30 min (from 108±9.3 to 119±12 bpm and from 112±8.9 to 122±11 bpm, respectively). However, there was no significant difference between HR in APE and that in LPE. Oxygen uptake was maintained throughout the two exercises. Skin blood flow, deep temperature, and total Hb (blood volume) in resting muscle continuously increased for 30 min of exercise during both APE and LPE. During both APE and LPE, there was a significant positive correlation between total Hb and deep temperature in all subjects. Moreover, there was a significant positive correlation between HR and total Hb (in seven out of eight subjects) during LPE. However, during APE, there was no positive correlation between HR and total Hb (r=0.391). These findings suggest that an increase of blood pooling in resting muscle could be proposed as one of the mechanisms underlying HR upward drift during moderately prolonged exercise.

  15. Direction of Influence between Posttraumatic and Depressive Symptoms during Prolonged Exposure Therapy among Children and Adolescents

    ERIC Educational Resources Information Center

    Aderka, Idan M.; Foa, Edna B.; Applebaum, Edna; Shafran, Naama; Gilboa-Schechtman, Eva

    2011-01-01

    Objective: Our objective in the present study was to examine the temporal sequencing of posttraumatic and depressive symptoms during prolonged exposure therapy for posttraumatic stress disorder (PTSD) among children and adolescents. Method: Participants were 73 children and adolescents (56.2% female) between the ages of 8 and 18. Participants…

  16. Associations between Prolonged Grief Disorder, Depression, Posttraumatic Stress Disorder, and Anxiety in Rwandan Genocide Survivors

    ERIC Educational Resources Information Center

    Schaal, Susanne; Dusingizemungu, Jean-Pierre; Jacob, Nadja; Neuner, Frank; Elbert, Thomas

    2012-01-01

    A number of studies have demonstrated that symptoms of prolonged grief disorder (PGD) represent a symptom cluster distinct from bereavement-related depression, anxiety, and posttraumatic stress disorder (PTSD). The aim of the present study was to confirm and extend these findings using the most recent criteria defining PGD. The authors interviewed…

  17. Prolonged Exposure Therapy for a Vietnam Veteran with PTSD and Early-Stage Dementia

    ERIC Educational Resources Information Center

    Duax, Jeanne M.; Waldron-Perrine, Brigid; Rauch, Sheila A. M.; Adams, Kenneth M.

    2013-01-01

    Although prolonged exposure therapy (PE) is considered an evidence-based treatment for PTSD, there has been little published about the use of this treatment for older adults with comorbid early-stage dementia. As the number of older adults in the United States continues to grow, so will their unique mental health needs. The present article…

  18. Prolonged fever and splinter hemorrhages in an immunocompetent traveler with disseminated histoplasmosis.

    PubMed

    Bitterman, Roni; Oren, Ilana; Geffen, Yuval; Sprecher, Hannah; Schwartz, Eli; Neuberger, Ami

    2013-01-01

    We present a case of progressive disseminated histoplasmosis in an immunocompetent traveler. Histoplasmosis was acquired in South America; its manifestations included prolonged fever, splinter hemorrhages, erythema multiforme, arthritis, and mediastinal lymphadenopathy. To the best of our knowledge no splinter hemorrhages had previously been reported in a patient with histoplasmosis.

  19. Effects of aging and life-prolonging diet on thyroid regulation of protein synthesis.

    PubMed

    Gromakova, I A; Konovalenko, O A

    2004-03-01

    The effect of thyroxin on the intensity of protein synthesis in rats of different age was studied during natural aging and in rats maintained on a low-caloric diet inhibiting aging. The intensity of protein synthesis decreased and the reaction to hormonal stimulus was absent in animals fed life-prolonging diet.

  20. Prolonged analgesia following preoperative bupivacaine neural blockade for oral surgery performed under general anesthesia.

    PubMed

    Chapman, P J; Ganendran, A

    1987-03-01

    The effectiveness of prolonged neural blockade following removal of impacted third molars under general anesthesia was evaluated in a controlled clinical study. There was a significant reduction in the amount of postoperative pain experienced, and no complications, either local or systemic, occurred. The technique has advantages, especially when general anesthesia is administered to outpatients.

  1. Prolonged Exposure Treatment of Chronic PTSD in Juvenile Sex Offenders: Promising Results from Two Case Studies

    ERIC Educational Resources Information Center

    Hunter, John A.

    2010-01-01

    Prolonged exposure (PE) was used to treat chronic PTSD secondary to severe developmental trauma in two adolescent male sex offenders referred for residential sex offender treatment. Both youth were treatment resistant prior to initiation of PE and showed evidence of long-standing irritability and depression/anxiety. Clinical observation and…

  2. Inhaled nitric oxide in preterm infants with prolonged preterm rupture of the membranes: a case series.

    PubMed

    Semberova, J; O'Donnell, S M; Franta, J; Miletin, J

    2015-04-01

    The available evidence does not support the routine use of inhaled nitric oxide (iNO) in the care of premature infants. We present a case series of 22 preterm infants born after prolonged preterm premature rupture of membranes and oligohydramnios with respiratory failure. Oxygenation index decreased significantly after commencement of iNO.

  3. Translation control during prolonged mTORC1 inhibition mediated by 4E-BP3

    PubMed Central

    Tsukumo, Yoshinori; Alain, Tommy; Fonseca, Bruno D.; Nadon, Robert; Sonenberg, Nahum

    2016-01-01

    Targeting mTORC1 is a highly promising strategy in cancer therapy. Suppression of mTORC1 activity leads to rapid dephosphorylation of eIF4E-binding proteins (4E-BP1–3) and subsequent inhibition of mRNA translation. However, how the different 4E-BPs affect translation during prolonged use of mTOR inhibitors is not known. Here we show that the expression of 4E-BP3, but not that of 4E-BP1 or 4E-BP2, is transcriptionally induced during prolonged mTORC1 inhibition in vitro and in vivo. Mechanistically, our data reveal that 4E-BP3 expression is controlled by the transcription factor TFE3 through a cis-regulatory element in the EIF4EBP3 gene promoter. CRISPR/Cas9-mediated EIF4EBP3 gene disruption in human cancer cells mitigated the inhibition of translation and proliferation caused by prolonged treatment with mTOR inhibitors. Our findings show that 4E-BP3 is an important effector of mTORC1 and a robust predictive biomarker of therapeutic response to prolonged treatment with mTOR-targeting drugs in cancer. PMID:27319316

  4. Physiological responses to prolonged bed rest in humans: A compendium of research, 1981-1988

    NASA Technical Reports Server (NTRS)

    Luu, Phuong B.; Ortiz, Vanessa; Barnes, Paul R.; Greenleaf, John E.

    1990-01-01

    Clinical observations and results form more basic studies that help to elucidate the physiological mechanisms of the adaptation of humans to prolonged bed rest. If the authors' abstract or summary was appropriate, it was included. In some cases a more detailed synopsis was provided under the subheadings of purpose, methods, results, and conclusions.

  5. Prolonged physiological reactivity and loss: Association of pupillary reactivity with negative thinking and feelings.

    PubMed

    Siegle, Greg J; D'Andrea, Wendy; Jones, Neil; Hallquist, Michael N; Stepp, Stephanie D; Fortunato, Andrea; Morse, Jennifer Q; Pilkonis, Paul A

    2015-11-01

    Prolonged psychophysiological reactions to negative information have long been associated with negative thinking and feeling. This association is operationalized in the RDoC negative affect construct of loss, which is nominally indexed by prolonged physiological reactivity, cognitive loss-related constructs such as rumination and guilt, and more feeling-related constructs such as sadness, crying, and anhedonia. These associations have not been tested explicitly. If thinking and feeling aspects of loss reflect different physiological mechanisms, as might be suggested by their putative neurobiology, different intervention pathways might be suggested. Here we examined the extent to which self-reported negative thinking and feeling constructs were associated with prolonged pupillary reactivity following negative words and a subsequent cognitive distractor in a diverse heterogeneously diagnosed sample of N=84 participants. We also considered indices of abuse and variables associated with borderline personality disorder as possible moderators. Consistently, feeling-related negative affect constructs were related to prolonged pupillary reactivity during the distractor after a negative stimulus whereas thinking-related constructs were not. These data suggest that people who have sustained physiological reactions to emotional stimuli may be more strongly characterized by non-linguistic negative feelings than explicit cognitions related to loss. Sustained physiological reactions could reflect efforts to regulate feeling states. In contrast to cognitive and affective variables, abuse was associated with decreased physiological reactivity, consistent with decreased neural engagement. Interventions that target mechanisms underlying feelings and their regulation may be more mechanistically specific to sustained reactivity than those which directly address cognitions.

  6. Oxidative Stress Interferes With White Matter Renewal After Prolonged Cerebral Hypoperfusion in Mice

    PubMed Central

    Miyamoto, Nobukazu; Maki, Takakuni; Pham, Loc-Duyen D.; Hayakawa, Kazuhide; Seo, Ji Hae; Mandeville, Emiri T.; Mandeville, Joseph B.; Kim, Kyu-Won; Lo, Eng H.; Arai, Ken

    2013-01-01

    Background and Purpose White matter injury caused by cerebral hypoperfusion may contribute to the pathophysiology of vascular dementia and stroke, but the underlying mechanisms remain to be fully defined. Here, we test the hypothesis that oxidative stress interferes with endogenous white matter repair by disrupting renewal processes mediated